use strict;
use warnings;
+use base qw/DBIx::Class/;
+use DBIx::Class::Carp;
+use DBIx::Class::ResultSetColumn;
+use Scalar::Util qw/blessed weaken/;
+use Try::Tiny;
+use Data::Compare (); # no imports!!! guard against insane architecture
+
+# not importing first() as it will clash with our own method
+use List::Util ();
+
+BEGIN {
+ # De-duplication in _merge_attr() is disabled, but left in for reference
+ # (the merger is used for other things that ought not to be de-duped)
+ *__HM_DEDUP = sub () { 0 };
+}
+
+use namespace::clean;
+
use overload
'0+' => "count",
'bool' => "_bool",
fallback => 1;
-use Carp::Clan qw/^DBIx::Class/;
-use Data::Page;
-use Storable;
-use DBIx::Class::ResultSetColumn;
-use DBIx::Class::ResultSourceHandle;
-use List::Util ();
-use Scalar::Util ();
-use base qw/DBIx::Class/;
-__PACKAGE__->mk_group_accessors('simple' => qw/result_class _source_handle/);
+__PACKAGE__->mk_group_accessors('simple' => qw/_result_class result_source/);
=head1 NAME
-DBIx::Class::ResultSet - Responsible for fetching and creating resultset.
+DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
=head1 SYNOPSIS
- my $rs = $schema->resultset('User')->search({ registered => 1 });
- my @rows = $schema->resultset('CD')->search({ year => 2005 })->all();
+ my $users_rs = $schema->resultset('User');
+ while( $user = $users_rs->next) {
+ print $user->username;
+ }
+
+ my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
+ my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
=head1 DESCRIPTION
-The resultset is also known as an iterator. It is responsible for handling
-queries that may return an arbitrary number of rows, e.g. via L</search>
-or a C<has_many> relationship.
+A ResultSet is an object which stores a set of conditions representing
+a query. It is the backbone of DBIx::Class (i.e. the really
+important/useful bit).
-In the examples below, the following table classes are used:
+No SQL is executed on the database when a ResultSet is created, it
+just stores all the conditions needed to create the query.
- package MyApp::Schema::Artist;
- use base qw/DBIx::Class/;
- __PACKAGE__->load_components(qw/Core/);
- __PACKAGE__->table('artist');
- __PACKAGE__->add_columns(qw/artistid name/);
- __PACKAGE__->set_primary_key('artistid');
- __PACKAGE__->has_many(cds => 'MyApp::Schema::CD');
- 1;
+A basic ResultSet representing the data of an entire table is returned
+by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
+L<Source|DBIx::Class::Manual::Glossary/Source> name.
- package MyApp::Schema::CD;
- use base qw/DBIx::Class/;
- __PACKAGE__->load_components(qw/Core/);
- __PACKAGE__->table('cd');
- __PACKAGE__->add_columns(qw/cdid artist title year/);
- __PACKAGE__->set_primary_key('cdid');
- __PACKAGE__->belongs_to(artist => 'MyApp::Schema::Artist');
- 1;
+ my $users_rs = $schema->resultset('User');
+
+A new ResultSet is returned from calling L</search> on an existing
+ResultSet. The new one will contain all the conditions of the
+original, plus any new conditions added in the C<search> call.
-=head1 OVERLOADING
+A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
+can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
+represents.
+
+The query that the ResultSet represents is B<only> executed against
+the database when these methods are called:
+L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
If a resultset is used in a numeric context it returns the L</count>.
-However, if it is used in a booleand context it is always true. So if
-you want to check if a resultset has any results use C<if $rs != 0>.
-C<if $rs> will always be true.
+However, if it is used in a boolean context it is B<always> true. So if
+you want to check if a resultset has any results, you must use C<if $rs
+!= 0>.
+
+=head1 CUSTOM ResultSet CLASSES THAT USE Moose
+
+If you want to make your custom ResultSet classes with L<Moose>, use a template
+similar to:
+
+ package MyApp::Schema::ResultSet::User;
+
+ use Moose;
+ use namespace::autoclean;
+ use MooseX::NonMoose;
+ extends 'DBIx::Class::ResultSet';
+
+ sub BUILDARGS { $_[2] }
+
+ ...your code...
+
+ __PACKAGE__->meta->make_immutable;
+
+ 1;
+
+The L<MooseX::NonMoose> is necessary so that the L<Moose> constructor does not
+clash with the regular ResultSet constructor. Alternatively, you can use:
+
+ __PACKAGE__->meta->make_immutable(inline_constructor => 0);
+
+The L<BUILDARGS|Moose::Manual::Construction/BUILDARGS> is necessary because the
+signature of the ResultSet C<new> is C<< ->new($source, \%args) >>.
+
+=head1 EXAMPLES
+
+=head2 Chaining resultsets
+
+Let's say you've got a query that needs to be run to return some data
+to the user. But, you have an authorization system in place that
+prevents certain users from seeing certain information. So, you want
+to construct the basic query in one method, but add constraints to it in
+another.
+
+ sub get_data {
+ my $self = shift;
+ my $request = $self->get_request; # Get a request object somehow.
+ my $schema = $self->result_source->schema;
+
+ my $cd_rs = $schema->resultset('CD')->search({
+ title => $request->param('title'),
+ year => $request->param('year'),
+ });
+
+ $cd_rs = $self->apply_security_policy( $cd_rs );
+
+ return $cd_rs->all();
+ }
+
+ sub apply_security_policy {
+ my $self = shift;
+ my ($rs) = @_;
+
+ return $rs->search({
+ subversive => 0,
+ });
+ }
+
+=head3 Resolving conditions and attributes
+
+When a resultset is chained from another resultset, conditions and
+attributes with the same keys need resolving.
+
+L</join>, L</prefetch>, L</+select>, L</+as> attributes are merged
+into the existing ones from the original resultset.
+
+The L</where> and L</having> attributes, and any search conditions, are
+merged with an SQL C<AND> to the existing condition from the original
+resultset.
+
+All other attributes are overridden by any new ones supplied in the
+search attributes.
+
+=head2 Multiple queries
+
+Since a resultset just defines a query, you can do all sorts of
+things with it with the same object.
+
+ # Don't hit the DB yet.
+ my $cd_rs = $schema->resultset('CD')->search({
+ title => 'something',
+ year => 2009,
+ });
+
+ # Each of these hits the DB individually.
+ my $count = $cd_rs->count;
+ my $most_recent = $cd_rs->get_column('date_released')->max();
+ my @records = $cd_rs->all;
+
+And it's not just limited to SELECT statements.
+
+ $cd_rs->delete();
+
+This is even cooler:
+
+ $cd_rs->create({ artist => 'Fred' });
+
+Which is the same as:
+
+ $schema->resultset('CD')->create({
+ title => 'something',
+ year => 2009,
+ artist => 'Fred'
+ });
+
+See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
=head1 METHODS
=over 4
-=item Arguments: $source, \%$attrs
+=item Arguments: L<$source|DBIx::Class::ResultSource>, L<\%attrs?|/ATTRIBUTES>
-=item Return Value: $rs
+=item Return Value: L<$resultset|/search>
=back
L</ATTRIBUTES> below). Does not perform any queries -- these are
executed as needed by the other methods.
-Generally you won't need to construct a resultset manually. You'll
-automatically get one from e.g. a L</search> called in scalar context:
+Generally you never construct a resultset manually. Instead you get one
+from e.g. a
+C<< $schema->L<resultset|DBIx::Class::Schema/resultset>('$source_name') >>
+or C<< $another_resultset->L<search|/search>(...) >> (the later called in
+scalar context):
my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
-IMPORTANT: If called on an object, proxies to new_result instead so
+=over
+
+=item WARNING
+
+If called on an object, proxies to L</new_result> instead, so
my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
-will return a CD object, not a ResultSet.
+will return a CD object, not a ResultSet, and is equivalent to:
+
+ my $cd = $schema->resultset('CD')->new_result({ title => 'Spoon' });
+
+Please also keep in mind that many internals call L</new_result> directly,
+so overloading this method with the idea of intercepting new result object
+creation B<will not work>. See also warning pertaining to L</create>.
+
+=back
=cut
return $class->new_result(@_) if ref $class;
my ($source, $attrs) = @_;
- $source = $source->handle
- unless $source->isa('DBIx::Class::ResultSourceHandle');
+ $source = $source->resolve
+ if $source->isa('DBIx::Class::ResultSourceHandle');
$attrs = { %{$attrs||{}} };
if ($attrs->{page}) {
$attrs->{alias} ||= 'me';
- # Creation of {} and bless separated to mitigate RH perl bug
- # see https://bugzilla.redhat.com/show_bug.cgi?id=196836
- my $self = {
- _source_handle => $source,
- result_class => $attrs->{result_class} || $source->resolve->result_class,
+ my $self = bless {
+ result_source => $source,
cond => $attrs->{where},
- count => undef,
pager => undef,
- attrs => $attrs
- };
+ attrs => $attrs,
+ }, $class;
- bless $self, $class;
+ # if there is a dark selector, this means we are already in a
+ # chain and the cleanup/sanification was taken care of by
+ # _search_rs already
+ $self->_normalize_selection($attrs)
+ unless $attrs->{_dark_selector};
- return $self;
+ $self->result_class(
+ $attrs->{result_class} || $source->result_class
+ );
+
+ $self;
}
=head2 search
=over 4
-=item Arguments: $cond, \%attrs?
+=item Arguments: L<$cond|DBIx::Class::SQLMaker> | undef, L<\%attrs?|/ATTRIBUTES>
-=item Return Value: $resultset (scalar context), @row_objs (list context)
+=item Return Value: $resultset (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
=back
my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
# year = 2005 OR year = 2004
+In list context, C<< ->all() >> is called implicitly on the resultset, thus
+returning a list of L<result|DBIx::Class::Manual::ResultClass> objects instead.
+To avoid that, use L</search_rs>.
+
If you need to pass in additional attributes but no additional condition,
call it as C<search(undef, \%attrs)>.
For a list of attributes that can be passed to C<search>, see
L</ATTRIBUTES>. For more examples of using this function, see
L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
-documentation for the first argument, see L<SQL::Abstract>.
+documentation for the first argument, see L<SQL::Abstract>
+and its extension L<DBIx::Class::SQLMaker>.
For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
+=head3 CAVEAT
+
+Note that L</search> does not process/deflate any of the values passed in the
+L<SQL::Abstract>-compatible search condition structure. This is unlike other
+condition-bound methods L</new_result>, L</create> and L</find>. The user must ensure
+manually that any value passed to this method will stringify to something the
+RDBMS knows how to deal with. A notable example is the handling of L<DateTime>
+objects, for more info see:
+L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
+
=cut
sub search {
my $self = shift;
my $rs = $self->search_rs( @_ );
- return (wantarray ? $rs->all : $rs);
+
+ if (wantarray) {
+ return $rs->all;
+ }
+ elsif (defined wantarray) {
+ return $rs;
+ }
+ else {
+ # we can be called by a relationship helper, which in
+ # turn may be called in void context due to some braindead
+ # overload or whatever else the user decided to be clever
+ # at this particular day. Thus limit the exception to
+ # external code calls only
+ $self->throw_exception ('->search is *not* a mutator, calling it in void context makes no sense')
+ if (caller)[0] !~ /^\QDBIx::Class::/;
+
+ return ();
+ }
}
=head2 search_rs
=over 4
-=item Arguments: $cond, \%attrs?
+=item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
-=item Return Value: $resultset
+=item Return Value: L<$resultset|/search>
=back
sub search_rs {
my $self = shift;
- my $attrs = {};
- $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
- my $our_attrs = { %{$self->{attrs}} };
- my $having = delete $our_attrs->{having};
- my $where = delete $our_attrs->{where};
+ my $rsrc = $self->result_source;
+ my ($call_cond, $call_attrs);
+
+ # Special-case handling for (undef, undef) or (undef)
+ # Note that (foo => undef) is valid deprecated syntax
+ @_ = () if not scalar grep { defined $_ } @_;
- my $rows;
+ # just a cond
+ if (@_ == 1) {
+ $call_cond = shift;
+ }
+ # fish out attrs in the ($condref, $attr) case
+ elsif (@_ == 2 and ( ! defined $_[0] or (ref $_[0]) ne '') ) {
+ ($call_cond, $call_attrs) = @_;
+ }
+ elsif (@_ % 2) {
+ $self->throw_exception('Odd number of arguments to search')
+ }
+ # legacy search
+ elsif (@_) {
+ carp_unique 'search( %condition ) is deprecated, use search( \%condition ) instead'
+ unless $rsrc->result_class->isa('DBIx::Class::CDBICompat');
+
+ for my $i (0 .. $#_) {
+ next if $i % 2;
+ $self->throw_exception ('All keys in condition key/value pairs must be plain scalars')
+ if (! defined $_[$i] or ref $_[$i] ne '');
+ }
+ $call_cond = { @_ };
+ }
+
+ # see if we can keep the cache (no $rs changes)
+ my $cache;
my %safe = (alias => 1, cache => 1);
+ if ( ! List::Util::first { !$safe{$_} } keys %$call_attrs and (
+ ! defined $_[0]
+ or
+ ref $_[0] eq 'HASH' && ! keys %{$_[0]}
+ or
+ ref $_[0] eq 'ARRAY' && ! @{$_[0]}
+ )) {
+ $cache = $self->get_cache;
+ }
- unless (
- (@_ && defined($_[0])) # @_ == () or (undef)
- ||
- (keys %$attrs # empty attrs or only 'safe' attrs
- && List::Util::first { !$safe{$_} } keys %$attrs)
- ) {
- # no search, effectively just a clone
- $rows = $self->get_cache;
- }
-
- my $new_attrs = { %{$our_attrs}, %{$attrs} };
-
- # merge new attrs into inherited
- foreach my $key (qw/join prefetch/) {
- next unless exists $attrs->{$key};
- $new_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key});
- }
-
- my $cond = (@_
- ? (
- (@_ == 1 || ref $_[0] eq "HASH")
- ? (
- (ref $_[0] eq 'HASH')
- ? (
- (keys %{ $_[0] } > 0)
- ? shift
- : undef
- )
- : shift
- )
- : (
- (@_ % 2)
- ? $self->throw_exception("Odd number of arguments to search")
- : {@_}
- )
- )
- : undef
- );
+ my $old_attrs = { %{$self->{attrs}} };
+ my $old_having = delete $old_attrs->{having};
+ my $old_where = delete $old_attrs->{where};
- if (defined $where) {
- $new_attrs->{where} = (
- defined $new_attrs->{where}
- ? { '-and' => [
- map {
- ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
- } $where, $new_attrs->{where}
- ]
- }
- : $where);
+ my $new_attrs = { %$old_attrs };
+
+ # take care of call attrs (only if anything is changing)
+ if ($call_attrs and keys %$call_attrs) {
+
+ # copy for _normalize_selection
+ $call_attrs = { %$call_attrs };
+
+ my @selector_attrs = qw/select as columns cols +select +as +columns include_columns/;
+
+ # reset the current selector list if new selectors are supplied
+ if (List::Util::first { exists $call_attrs->{$_} } qw/columns cols select as/) {
+ delete @{$old_attrs}{(@selector_attrs, '_dark_selector')};
+ }
+
+ # Normalize the new selector list (operates on the passed-in attr structure)
+ # Need to do it on every chain instead of only once on _resolved_attrs, in
+ # order to allow detection of empty vs partial 'as'
+ $call_attrs->{_dark_selector} = $old_attrs->{_dark_selector}
+ if $old_attrs->{_dark_selector};
+ $self->_normalize_selection ($call_attrs);
+
+ # start with blind overwriting merge, exclude selector attrs
+ $new_attrs = { %{$old_attrs}, %{$call_attrs} };
+ delete @{$new_attrs}{@selector_attrs};
+
+ for (@selector_attrs) {
+ $new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
+ if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
+ }
+
+ # older deprecated name, use only if {columns} is not there
+ if (my $c = delete $new_attrs->{cols}) {
+ if ($new_attrs->{columns}) {
+ carp "Resultset specifies both the 'columns' and the legacy 'cols' attributes - ignoring 'cols'";
+ }
+ else {
+ $new_attrs->{columns} = $c;
+ }
+ }
+
+
+ # join/prefetch use their own crazy merging heuristics
+ foreach my $key (qw/join prefetch/) {
+ $new_attrs->{$key} = $self->_merge_joinpref_attr($old_attrs->{$key}, $call_attrs->{$key})
+ if exists $call_attrs->{$key};
+ }
+
+ # stack binds together
+ $new_attrs->{bind} = [ @{ $old_attrs->{bind} || [] }, @{ $call_attrs->{bind} || [] } ];
}
- if (defined $cond) {
- $new_attrs->{where} = (
- defined $new_attrs->{where}
- ? { '-and' => [
- map {
- ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
- } $cond, $new_attrs->{where}
- ]
- }
- : $cond);
+
+ for ($old_where, $call_cond) {
+ if (defined $_) {
+ $new_attrs->{where} = $self->_stack_cond (
+ $_, $new_attrs->{where}
+ );
+ }
}
- if (defined $having) {
- $new_attrs->{having} = (
- defined $new_attrs->{having}
- ? { '-and' => [
- map {
- ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
- } $having, $new_attrs->{having}
- ]
+ if (defined $old_having) {
+ $new_attrs->{having} = $self->_stack_cond (
+ $old_having, $new_attrs->{having}
+ )
+ }
+
+ my $rs = (ref $self)->new($rsrc, $new_attrs);
+
+ $rs->set_cache($cache) if ($cache);
+
+ return $rs;
+}
+
+my $dark_sel_dumper;
+sub _normalize_selection {
+ my ($self, $attrs) = @_;
+
+ # legacy syntax
+ $attrs->{'+columns'} = $self->_merge_attr($attrs->{'+columns'}, delete $attrs->{include_columns})
+ if exists $attrs->{include_columns};
+
+ # columns are always placed first, however
+
+ # Keep the X vs +X separation until _resolved_attrs time - this allows to
+ # delay the decision on whether to use a default select list ($rsrc->columns)
+ # allowing stuff like the remove_columns helper to work
+ #
+ # select/as +select/+as pairs need special handling - the amount of select/as
+ # elements in each pair does *not* have to be equal (think multicolumn
+ # selectors like distinct(foo, bar) ). If the selector is bare (no 'as'
+ # supplied at all) - try to infer the alias, either from the -as parameter
+ # of the selector spec, or use the parameter whole if it looks like a column
+ # name (ugly legacy heuristic). If all fails - leave the selector bare (which
+ # is ok as well), but make sure no more additions to the 'as' chain take place
+ for my $pref ('', '+') {
+
+ my ($sel, $as) = map {
+ my $key = "${pref}${_}";
+
+ my $val = [ ref $attrs->{$key} eq 'ARRAY'
+ ? @{$attrs->{$key}}
+ : $attrs->{$key} || ()
+ ];
+ delete $attrs->{$key};
+ $val;
+ } qw/select as/;
+
+ if (! @$as and ! @$sel ) {
+ next;
+ }
+ elsif (@$as and ! @$sel) {
+ $self->throw_exception(
+ "Unable to handle ${pref}as specification (@$as) without a corresponding ${pref}select"
+ );
+ }
+ elsif( ! @$as ) {
+ # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
+ # if any @$as has been supplied we assume the user knows what (s)he is doing
+ # and blindly keep stacking up pieces
+ unless ($attrs->{_dark_selector}) {
+ SELECTOR:
+ for (@$sel) {
+ if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
+ push @$as, $_->{-as};
+ }
+ # assume any plain no-space, no-parenthesis string to be a column spec
+ # FIXME - this is retarded but is necessary to support shit like 'count(foo)'
+ elsif ( ! ref $_ and $_ =~ /^ [^\s\(\)]+ $/x) {
+ push @$as, $_;
}
- : $having);
+ # if all else fails - raise a flag that no more aliasing will be allowed
+ else {
+ $attrs->{_dark_selector} = {
+ plus_stage => $pref,
+ string => ($dark_sel_dumper ||= do {
+ require Data::Dumper::Concise;
+ Data::Dumper::Concise::DumperObject()->Indent(0);
+ })->Values([$_])->Dump
+ ,
+ };
+ last SELECTOR;
+ }
+ }
+ }
+ }
+ elsif (@$as < @$sel) {
+ $self->throw_exception(
+ "Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
+ );
+ }
+ elsif ($pref and $attrs->{_dark_selector}) {
+ $self->throw_exception(
+ "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
+ );
+ }
+
+
+ # merge result
+ $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
+ $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
+ }
+}
+
+sub _stack_cond {
+ my ($self, $left, $right) = @_;
+
+ # collapse single element top-level conditions
+ # (single pass only, unlikely to need recursion)
+ for ($left, $right) {
+ if (ref $_ eq 'ARRAY') {
+ if (@$_ == 0) {
+ $_ = undef;
+ }
+ elsif (@$_ == 1) {
+ $_ = $_->[0];
+ }
+ }
+ elsif (ref $_ eq 'HASH') {
+ my ($first, $more) = keys %$_;
+
+ # empty hash
+ if (! defined $first) {
+ $_ = undef;
+ }
+ # one element hash
+ elsif (! defined $more) {
+ if ($first eq '-and' and ref $_->{'-and'} eq 'HASH') {
+ $_ = $_->{'-and'};
+ }
+ elsif ($first eq '-or' and ref $_->{'-or'} eq 'ARRAY') {
+ $_ = $_->{'-or'};
+ }
+ }
+ }
+ }
+
+ # merge hashes with weeding out of duplicates (simple cases only)
+ if (ref $left eq 'HASH' and ref $right eq 'HASH') {
+
+ # shallow copy to destroy
+ $right = { %$right };
+ for (grep { exists $right->{$_} } keys %$left) {
+ # the use of eq_deeply here is justified - the rhs of an
+ # expression can contain a lot of twisted weird stuff
+ delete $right->{$_} if Data::Compare::Compare( $left->{$_}, $right->{$_} );
+ }
+
+ $right = undef unless keys %$right;
}
- my $rs = (ref $self)->new($self->result_source, $new_attrs);
- if ($rows) {
- $rs->set_cache($rows);
+
+ if (defined $left xor defined $right) {
+ return defined $left ? $left : $right;
+ }
+ elsif (! defined $left) {
+ return undef;
+ }
+ else {
+ return { -and => [ $left, $right ] };
}
- return $rs;
}
=head2 search_literal
+B<CAVEAT>: C<search_literal> is provided for Class::DBI compatibility and
+should only be used in that context. C<search_literal> is a convenience
+method. It is equivalent to calling C<< $schema->search(\[]) >>, but if you
+want to ensure columns are bound correctly, use L</search>.
+
+See L<DBIx::Class::Manual::Cookbook/Searching> and
+L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
+require C<search_literal>.
+
=over 4
-=item Arguments: $sql_fragment, @bind_values
+=item Arguments: $sql_fragment, @standalone_bind_values
-=item Return Value: $resultset (scalar context), @row_objs (list context)
+=item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
=back
Pass a literal chunk of SQL to be added to the conditional part of the
resultset query.
-CAVEAT: C<search_literal> is provided for Class::DBI compatibility and should
-only be used in that context. There are known problems using C<search_literal>
-in chained queries; it can result in bind values in the wrong order. See
-L<DBIx::Class::Manual::Cookbook/Searching> and
-L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
-require C<search_literal>.
+Example of how to use C<search> instead of C<search_literal>
+
+ my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
+ my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
=cut
sub search_literal {
- my ($self, $cond, @vals) = @_;
- my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {});
- $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ];
- return $self->search(\$cond, $attrs);
+ my ($self, $sql, @bind) = @_;
+ my $attr;
+ if ( @bind && ref($bind[-1]) eq 'HASH' ) {
+ $attr = pop @bind;
+ }
+ return $self->search(\[ $sql, map [ {} => $_ ], @bind ], ($attr || () ));
}
=head2 find
=over 4
-=item Arguments: @values | \%cols, \%attrs?
+=item Arguments: \%columns_values | @pk_values, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
-=item Return Value: $row_object
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
=back
-Finds a row based on its primary key or unique constraint. For example, to find
-a row by its primary key:
+Finds and returns a single row based on supplied criteria. Takes either a
+hashref with the same format as L</create> (including inference of foreign
+keys from related objects), or a list of primary key values in the same
+order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
+declaration on the L</result_source>.
+
+In either case an attempt is made to combine conditions already existing on
+the resultset with the condition passed to this method.
+
+To aid with preparing the correct query for the storage you may supply the
+C<key> attribute, which is the name of a
+L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
+unique constraint corresponding to the
+L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
+C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
+to construct a query that satisfies the named unique constraint fully (
+non-NULL values for each column member of the constraint) an exception is
+thrown.
+
+If no C<key> is specified, the search is carried over all unique constraints
+which are fully defined by the available condition.
+
+If no such constraint is found, C<find> currently defaults to a simple
+C<< search->(\%column_values) >> which may or may not do what you expect.
+Note that this fallback behavior may be deprecated in further versions. If
+you need to search with arbitrary conditions - use L</search>. If the query
+resulting from this fallback produces more than one row, a warning to the
+effect is issued, though only the first row is constructed and returned as
+C<$result_object>.
+
+In addition to C<key>, L</find> recognizes and applies standard
+L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
+
+Note that if you have extra concerns about the correctness of the resulting
+query you need to specify the C<key> attribute and supply the entire condition
+as an argument to find (since it is not always possible to perform the
+combination of the resultset condition with the supplied one, especially if
+the resultset condition contains literal sql).
+
+For example, to find a row by its primary key:
my $cd = $schema->resultset('CD')->find(5);
-You can also find a row by a specific unique constraint using the C<key>
-attribute. For example:
-
- my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
- key => 'cd_artist_title'
- });
-
-Additionally, you can specify the columns explicitly by name:
+You can also find a row by a specific unique constraint:
my $cd = $schema->resultset('CD')->find(
{
{ key => 'cd_artist_title' }
);
-If the C<key> is specified as C<primary>, it searches only on the primary key.
-
-If no C<key> is specified, it searches on all unique constraints defined on the
-source for which column data is provided, including the primary key.
-
-If your table does not have a primary key, you B<must> provide a value for the
-C<key> attribute matching one of the unique constraints on the source.
-
-Note: If your query does not return only one row, a warning is generated:
-
- Query returned more than one row
-
-See also L</find_or_create> and L</update_or_create>. For information on how to
-declare unique constraints, see
-L<DBIx::Class::ResultSource/add_unique_constraint>.
+See also L</find_or_create> and L</update_or_create>.
=cut
my $self = shift;
my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
- # Default to the primary key, but allow a specific key
- my @cols = exists $attrs->{key}
- ? $self->result_source->unique_constraint_columns($attrs->{key})
- : $self->result_source->primary_columns;
- $self->throw_exception(
- "Can't find unless a primary key is defined or unique constraint is specified"
- ) unless @cols;
+ my $rsrc = $self->result_source;
- # Parse out a hashref from input
- my $input_query;
- if (ref $_[0] eq 'HASH') {
- $input_query = { %{$_[0]} };
+ my $constraint_name;
+ if (exists $attrs->{key}) {
+ $constraint_name = defined $attrs->{key}
+ ? $attrs->{key}
+ : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
+ ;
}
- elsif (@_ == @cols) {
- $input_query = {};
- @{$input_query}{@cols} = @_;
+
+ # Parse out the condition from input
+ my $call_cond;
+
+ if (ref $_[0] eq 'HASH') {
+ $call_cond = { %{$_[0]} };
}
else {
- # Compatibility: Allow e.g. find(id => $value)
- carp "Find by key => value deprecated; please use a hashref instead";
- $input_query = {@_};
- }
-
- my (%related, $info);
-
- KEY: foreach my $key (keys %$input_query) {
- if (ref($input_query->{$key})
- && ($info = $self->result_source->relationship_info($key))) {
- my $val = delete $input_query->{$key};
- next KEY if (ref($val) eq 'ARRAY'); # has_many for multi_create
- my $rel_q = $self->result_source->resolve_condition(
- $info->{cond}, $val, $key
- );
- die "Can't handle OR join condition in find" if ref($rel_q) eq 'ARRAY';
+ # if only values are supplied we need to default to 'primary'
+ $constraint_name = 'primary' unless defined $constraint_name;
+
+ my @c_cols = $rsrc->unique_constraint_columns($constraint_name);
+
+ $self->throw_exception(
+ "No constraint columns, maybe a malformed '$constraint_name' constraint?"
+ ) unless @c_cols;
+
+ $self->throw_exception (
+ 'find() expects either a column/value hashref, or a list of values '
+ . "corresponding to the columns of the specified unique constraint '$constraint_name'"
+ ) unless @c_cols == @_;
+
+ $call_cond = {};
+ @{$call_cond}{@c_cols} = @_;
+ }
+
+ my %related;
+ for my $key (keys %$call_cond) {
+ if (
+ my $keyref = ref($call_cond->{$key})
+ and
+ my $relinfo = $rsrc->relationship_info($key)
+ ) {
+ my $val = delete $call_cond->{$key};
+
+ next if $keyref eq 'ARRAY'; # has_many for multi_create
+
+ my $rel_q = $rsrc->_resolve_condition(
+ $relinfo->{cond}, $val, $key, $key
+ );
+ die "Can't handle complex relationship conditions in find" if ref($rel_q) ne 'HASH';
@related{keys %$rel_q} = values %$rel_q;
}
}
- if (my @keys = keys %related) {
- @{$input_query}{@keys} = values %related;
- }
+ # relationship conditions take precedence (?)
+ @{$call_cond}{keys %related} = values %related;
- # Build the final query: Default to the disjunction of the unique queries,
- # but allow the input query in case the ResultSet defines the query or the
- # user is abusing find
my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
- my $query;
- if (exists $attrs->{key}) {
- my @unique_cols = $self->result_source->unique_constraint_columns($attrs->{key});
- my $unique_query = $self->_build_unique_query($input_query, \@unique_cols);
- $query = $self->_add_alias($unique_query, $alias);
+ my $final_cond;
+ if (defined $constraint_name) {
+ $final_cond = $self->_qualify_cond_columns (
+
+ $self->_build_unique_cond (
+ $constraint_name,
+ $call_cond,
+ ),
+
+ $alias,
+ );
+ }
+ elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
+ # This means that we got here after a merger of relationship conditions
+ # in ::Relationship::Base::search_related (the row method), and furthermore
+ # the relationship is of the 'single' type. This means that the condition
+ # provided by the relationship (already attached to $self) is sufficient,
+ # as there can be only one row in the database that would satisfy the
+ # relationship
}
else {
- my @unique_queries = $self->_unique_queries($input_query, $attrs);
- $query = @unique_queries
- ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
- : $self->_add_alias($input_query, $alias);
+ # no key was specified - fall down to heuristics mode:
+ # run through all unique queries registered on the resultset, and
+ # 'OR' all qualifying queries together
+ my (@unique_queries, %seen_column_combinations);
+ for my $c_name ($rsrc->unique_constraint_names) {
+ next if $seen_column_combinations{
+ join "\x00", sort $rsrc->unique_constraint_columns($c_name)
+ }++;
+
+ push @unique_queries, try {
+ $self->_build_unique_cond ($c_name, $call_cond, 'croak_on_nulls')
+ } || ();
+ }
+
+ $final_cond = @unique_queries
+ ? [ map { $self->_qualify_cond_columns($_, $alias) } @unique_queries ]
+ : $self->_non_unique_find_fallback ($call_cond, $attrs)
+ ;
}
- # Run the query
- if (keys %$attrs) {
- my $rs = $self->search($query, $attrs);
- if (keys %{$rs->_resolved_attrs->{collapse}}) {
- my $row = $rs->next;
- carp "Query returned more than one row" if $rs->next;
- return $row;
- }
- else {
- return $rs->single;
- }
+ # Run the query, passing the result_class since it should propagate for find
+ my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
+ if ($rs->_resolved_attrs->{collapse}) {
+ my $row = $rs->next;
+ carp "Query returned more than one row" if $rs->next;
+ return $row;
}
else {
- if (keys %{$self->_resolved_attrs->{collapse}}) {
- my $rs = $self->search($query);
- my $row = $rs->next;
- carp "Query returned more than one row" if $rs->next;
- return $row;
- }
- else {
- return $self->single($query);
- }
+ return $rs->single;
}
}
-# _add_alias
+# This is a stop-gap method as agreed during the discussion on find() cleanup:
+# http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
+#
+# It is invoked when find() is called in legacy-mode with insufficiently-unique
+# condition. It is provided for overrides until a saner way forward is devised
#
-# Add the specified alias to the specified query hash. A copy is made so the
-# original query is not modified.
+# *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
+# the road. Please adjust your tests accordingly to catch this situation early
+# DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
+#
+# The method will not be removed without an adequately complete replacement
+# for strict-mode enforcement
+sub _non_unique_find_fallback {
+ my ($self, $cond, $attrs) = @_;
+
+ return $self->_qualify_cond_columns(
+ $cond,
+ exists $attrs->{alias}
+ ? $attrs->{alias}
+ : $self->{attrs}{alias}
+ );
+}
-sub _add_alias {
- my ($self, $query, $alias) = @_;
- my %aliased = %$query;
- foreach my $col (grep { ! m/\./ } keys %aliased) {
- $aliased{"$alias.$col"} = delete $aliased{$col};
+sub _qualify_cond_columns {
+ my ($self, $cond, $alias) = @_;
+
+ my %aliased = %$cond;
+ for (keys %aliased) {
+ $aliased{"$alias.$_"} = delete $aliased{$_}
+ if $_ !~ /\./;
}
return \%aliased;
}
-# _unique_queries
-#
-# Build a list of queries which satisfy unique constraints.
-
-sub _unique_queries {
- my ($self, $query, $attrs) = @_;
-
- my @constraint_names = exists $attrs->{key}
- ? ($attrs->{key})
- : $self->result_source->unique_constraint_names;
+sub _build_unique_cond {
+ my ($self, $constraint_name, $extra_cond, $croak_on_null) = @_;
- my $where = $self->_collapse_cond($self->{attrs}{where} || {});
- my $num_where = scalar keys %$where;
+ my @c_cols = $self->result_source->unique_constraint_columns($constraint_name);
- my @unique_queries;
- foreach my $name (@constraint_names) {
- my @unique_cols = $self->result_source->unique_constraint_columns($name);
- my $unique_query = $self->_build_unique_query($query, \@unique_cols);
+ # combination may fail if $self->{cond} is non-trivial
+ my ($final_cond) = try {
+ $self->_merge_with_rscond ($extra_cond)
+ } catch {
+ +{ %$extra_cond }
+ };
- my $num_cols = scalar @unique_cols;
- my $num_query = scalar keys %$unique_query;
+ # trim out everything not in $columns
+ $final_cond = { map {
+ exists $final_cond->{$_}
+ ? ( $_ => $final_cond->{$_} )
+ : ()
+ } @c_cols };
- my $total = $num_query + $num_where;
- if ($num_query && ($num_query == $num_cols || $total == $num_cols)) {
- # The query is either unique on its own or is unique in combination with
- # the existing where clause
- push @unique_queries, $unique_query;
- }
+ if (my @missing = grep
+ { ! ($croak_on_null ? defined $final_cond->{$_} : exists $final_cond->{$_}) }
+ (@c_cols)
+ ) {
+ $self->throw_exception( sprintf ( "Unable to satisfy requested constraint '%s', no values for column(s): %s",
+ $constraint_name,
+ join (', ', map { "'$_'" } @missing),
+ ) );
}
- return @unique_queries;
-}
-
-# _build_unique_query
-#
-# Constrain the specified query hash based on the specified column names.
-
-sub _build_unique_query {
- my ($self, $query, $unique_cols) = @_;
+ if (
+ !$croak_on_null
+ and
+ !$ENV{DBIC_NULLABLE_KEY_NOWARN}
+ and
+ my @undefs = sort grep { ! defined $final_cond->{$_} } (keys %$final_cond)
+ ) {
+ carp_unique ( sprintf (
+ "NULL/undef values supplied for requested unique constraint '%s' (NULL "
+ . 'values in column(s): %s). This is almost certainly not what you wanted, '
+ . 'though you can set DBIC_NULLABLE_KEY_NOWARN to disable this warning.',
+ $constraint_name,
+ join (', ', map { "'$_'" } @undefs),
+ ));
+ }
- return {
- map { $_ => $query->{$_} }
- grep { exists $query->{$_} }
- @$unique_cols
- };
+ return $final_cond;
}
=head2 search_related
=over 4
-=item Arguments: $rel, $cond, \%attrs?
+=item Arguments: $rel_name, $cond?, L<\%attrs?|/ATTRIBUTES>
-=item Return Value: $new_resultset
+=item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
=back
Searches the specified relationship, optionally specifying a condition and
attributes for matching records. See L</ATTRIBUTES> for more information.
+In list context, C<< ->all() >> is called implicitly on the resultset, thus
+returning a list of result objects instead. To avoid that, use L</search_related_rs>.
+
+See also L</search_related_rs>.
+
=cut
sub search_related {
=head2 search_related_rs
This method works exactly the same as search_related, except that
-it guarantees a restultset, even in list context.
+it guarantees a resultset, even in list context.
=cut
=item Arguments: none
-=item Return Value: $cursor
+=item Return Value: L<$cursor|DBIx::Class::Cursor>
=back
=cut
sub cursor {
- my ($self) = @_;
+ my $self = shift;
- my $attrs = { %{$self->_resolved_attrs} };
- return $self->{cursor}
- ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
- $attrs->{where},$attrs);
+ return $self->{cursor} ||= do {
+ my $attrs = { %{$self->_resolved_attrs } };
+ $self->result_source->storage->select(
+ $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
+ );
+ };
}
=head2 single
=over 4
-=item Arguments: $cond?
+=item Arguments: L<$cond?|DBIx::Class::SQLMaker>
-=item Return Value: $row_object?
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
=back
my $cd = $schema->resultset('CD')->single({ year => 2001 });
Inflates the first result without creating a cursor if the resultset has
-any records in it; if not returns nothing. Used by L</find> as an optimisation.
+any records in it; if not returns C<undef>. Used by L</find> as a lean version
+of L</search>.
+
+While this method can take an optional search condition (just like L</search>)
+being a fast-code-path it does not recognize search attributes. If you need to
+add extra joins or similar, call L</search> and then chain-call L</single> on the
+L<DBIx::Class::ResultSet> returned.
-Can optionally take an additional condition B<only> - this is a fast-code-path
-method; if you need to add extra joins or similar call L</search> and then
-L</single> without a condition on the L<DBIx::Class::ResultSet> returned from
-that.
+=over
-B<Note>: As of 0.08100, this method assumes that the query returns only one
-row. If more than one row is returned, you will receive a warning:
+=item B<Note>
+
+As of 0.08100, this method enforces the assumption that the preceding
+query returns only one row. If more than one row is returned, you will receive
+a warning:
Query returned more than one row
-In this case, you should be using L</first> or L</find> instead.
+In this case, you should be using L</next> or L</find> instead, or if you really
+know what you are doing, use the L</rows> attribute to explicitly limit the size
+of the resultset.
+
+This method will also throw an exception if it is called on a resultset prefetching
+has_many, as such a prefetch implies fetching multiple rows from the database in
+order to assemble the resulting object.
+
+=back
=cut
sub single {
my ($self, $where) = @_;
+ if(@_ > 2) {
+ $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
+ }
+
my $attrs = { %{$self->_resolved_attrs} };
+
+ $self->throw_exception(
+ 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
+ ) if $attrs->{collapse};
+
if ($where) {
if (defined $attrs->{where}) {
$attrs->{where} = {
}
}
-# XXX: Disabled since it doesn't infer uniqueness in all cases
-# unless ($self->_is_unique_query($attrs->{where})) {
-# carp "Query not guaranteed to return a single row"
-# . "; please declare your unique constraints or use search instead";
-# }
-
- my @data = $self->result_source->storage->select_single(
+ my $data = [ $self->result_source->storage->select_single(
$attrs->{from}, $attrs->{select},
$attrs->{where}, $attrs
- );
-
- return (@data ? ($self->_construct_object(@data))[0] : undef);
+ )];
+ return undef unless @$data;
+ $self->{stashed_rows} = [ $data ];
+ $self->_construct_objects->[0];
}
-# _is_unique_query
-#
-# Try to determine if the specified query is guaranteed to be unique, based on
-# the declared unique constraints.
-sub _is_unique_query {
- my ($self, $query) = @_;
+# _collapse_query
+#
+# Recursively collapse the query, accumulating values for each column.
- my $collapsed = $self->_collapse_query($query);
- my $alias = $self->{attrs}{alias};
+sub _collapse_query {
+ my ($self, $query, $collapsed) = @_;
- foreach my $name ($self->result_source->unique_constraint_names) {
- my @unique_cols = map {
- "$alias.$_"
- } $self->result_source->unique_constraint_columns($name);
-
- # Count the values for each unique column
- my %seen = map { $_ => 0 } @unique_cols;
-
- foreach my $key (keys %$collapsed) {
- my $aliased = $key =~ /\./ ? $key : "$alias.$key";
- next unless exists $seen{$aliased}; # Additional constraints are okay
- $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
- }
-
- # If we get 0 or more than 1 value for a column, it's not necessarily unique
- return 1 unless grep { $_ != 1 } values %seen;
- }
-
- return 0;
-}
-
-# _collapse_query
-#
-# Recursively collapse the query, accumulating values for each column.
-
-sub _collapse_query {
- my ($self, $query, $collapsed) = @_;
-
- $collapsed ||= {};
+ $collapsed ||= {};
if (ref $query eq 'ARRAY') {
foreach my $subquery (@$query) {
next unless ref $subquery; # -or
-# warn "ARRAY: " . Dumper $subquery;
$collapsed = $self->_collapse_query($subquery, $collapsed);
}
}
elsif (ref $query eq 'HASH') {
if (keys %$query and (keys %$query)[0] eq '-and') {
foreach my $subquery (@{$query->{-and}}) {
-# warn "HASH: " . Dumper $subquery;
$collapsed = $self->_collapse_query($subquery, $collapsed);
}
}
else {
-# warn "LEAF: " . Dumper $query;
foreach my $col (keys %$query) {
my $value = $query->{$col};
$collapsed->{$col}{$value}++;
=over 4
-=item Arguments: $cond?
+=item Arguments: L<$cond?|DBIx::Class::SQLMaker>
-=item Return Value: $resultsetcolumn
+=item Return Value: L<$resultsetcolumn|DBIx::Class::ResultSetColumn>
=back
=over 4
-=item Arguments: $cond, \%attrs?
+=item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
-=item Return Value: $resultset (scalar context), @row_objs (list context)
+=item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
=back
$cd_rs = $rs->search_like({ title => '%blue%'});
Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
-that this is simply a convenience method. You most likely want to use
-L</search> with specific operators.
+that this is simply a convenience method retained for ex Class::DBI users.
+You most likely want to use L</search> with specific operators.
For more information, see L<DBIx::Class::Manual::Cookbook>.
+This method is deprecated and will be removed in 0.09. Use L</search()>
+instead. An example conversion is:
+
+ ->search_like({ foo => 'bar' });
+
+ # Becomes
+
+ ->search({ foo => { like => 'bar' } });
+
=cut
sub search_like {
my $class = shift;
+ carp_unique (
+ 'search_like() is deprecated and will be removed in DBIC version 0.09.'
+ .' Instead use ->search({ x => { -like => "y%" } })'
+ .' (note the outer pair of {}s - they are important!)'
+ );
my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
$query->{$_} = { 'like' => $query->{$_} } for keys %$query;
=item Arguments: $first, $last
-=item Return Value: $resultset (scalar context), @row_objs (list context)
+=item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
=back
$attrs->{offset} = $self->{attrs}{offset} || 0;
$attrs->{offset} += $min;
$attrs->{rows} = ($max ? ($max - $min + 1) : 1);
- return $self->search(undef(), $attrs);
+ return $self->search(undef, $attrs);
#my $slice = (ref $self)->new($self->result_source, $attrs);
#return (wantarray ? $slice->all : $slice);
}
=item Arguments: none
-=item Return Value: $result?
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
=back
sub next {
my ($self) = @_;
+
if (my $cache = $self->get_cache) {
$self->{all_cache_position} ||= 0;
return $cache->[$self->{all_cache_position}++];
}
+
if ($self->{attrs}{cache}) {
+ delete $self->{pager};
$self->{all_cache_position} = 1;
return ($self->all)[0];
}
- if ($self->{stashed_objects}) {
- my $obj = shift(@{$self->{stashed_objects}});
- delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
- return $obj;
- }
- my @row = (
- exists $self->{stashed_row}
- ? @{delete $self->{stashed_row}}
- : $self->cursor->next
- );
- return undef unless (@row);
- my ($row, @more) = $self->_construct_object(@row);
- $self->{stashed_objects} = \@more if @more;
- return $row;
-}
-
-sub _construct_object {
- my ($self, @row) = @_;
- my $info = $self->_collapse_result($self->{_attrs}{as}, \@row);
- my @new = $self->result_class->inflate_result($self->result_source, @$info);
- @new = $self->{_attrs}{record_filter}->(@new)
- if exists $self->{_attrs}{record_filter};
- return @new;
-}
-
-sub _collapse_result {
- my ($self, $as_proto, $row) = @_;
-
- my @copy = @$row;
-
- # 'foo' => [ undef, 'foo' ]
- # 'foo.bar' => [ 'foo', 'bar' ]
- # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
- my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
+ return shift(@{$self->{stashed_objects}}) if @{ $self->{stashed_objects}||[] };
- my %collapse = %{$self->{_attrs}{collapse}||{}};
+ $self->{stashed_objects} = $self->_construct_objects
+ or return undef;
- my @pri_index;
-
- # if we're doing collapsing (has_many prefetch) we need to grab records
- # until the PK changes, so fill @pri_index. if not, we leave it empty so
- # we know we don't have to bother.
-
- # the reason for not using the collapse stuff directly is because if you
- # had for e.g. two artists in a row with no cds, the collapse info for
- # both would be NULL (undef) so you'd lose the second artist
-
- # store just the index so we can check the array positions from the row
- # without having to contruct the full hash
+ return shift @{$self->{stashed_objects}};
+}
- if (keys %collapse) {
- my %pri = map { ($_ => 1) } $self->result_source->primary_columns;
- foreach my $i (0 .. $#construct_as) {
- next if defined($construct_as[$i][0]); # only self table
- if (delete $pri{$construct_as[$i][1]}) {
- push(@pri_index, $i);
- }
- last unless keys %pri; # short circuit (Johnny Five Is Alive!)
- }
+# Constructs as many objects as it can in one pass while respecting
+# cursor laziness. Several modes of operation:
+#
+# * Always builds everything present in @{$self->{stashed_rows}}
+# * If called with $fetch_all true - pulls everything off the cursor and
+# builds all objects in one pass
+# * If $self->_resolved_attrs->{collapse} is true, checks the order_by
+# and if the resultset is ordered properly by the left side:
+# * Fetches stuff off the cursor until the "master object" changes,
+# and saves the last extra row (if any) in @{$self->{stashed_rows}}
+# OR
+# * Just fetches, and collapses/constructs everything as if $fetch_all
+# was requested (there is no other way to collapse except for an
+# eager cursor)
+# * If no collapse is requested - just get the next row, construct and
+# return
+sub _construct_objects {
+ my ($self, $fetch_all) = @_;
+
+ my $rsrc = $self->result_source;
+ my $attrs = $self->_resolved_attrs;
+ my $cursor = $self->cursor;
+
+ # this will be used as both initial raw-row collector AND as a RV of
+ # _construct_objects. Not regrowing the array twice matters a lot...
+ # a suprising amount actually
+ my $rows = (delete $self->{stashed_rows}) || [];
+ if ($fetch_all) {
+ # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
+ $rows = [ @$rows, $cursor->all ];
}
+ elsif (!$attrs->{collapse}) {
+ # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
+ push @$rows, do { my @r = $cursor->next; @r ? \@r : () }
+ unless @$rows;
+ }
+ else {
+ $attrs->{_ordered_for_collapse} ||= (!$attrs->{order_by}) ? undef : do {
+ my $st = $rsrc->schema->storage;
+ my @ord_cols = map
+ { $_->[0] }
+ ( $st->_extract_order_criteria($attrs->{order_by}) )
+ ;
+
+ my $colinfos = $st->_resolve_column_info($attrs->{from}, \@ord_cols);
+
+ for (0 .. $#ord_cols) {
+ if (
+ ! $colinfos->{$ord_cols[$_]}
+ or
+ $colinfos->{$ord_cols[$_]}{-result_source} != $rsrc
+ ) {
+ splice @ord_cols, $_;
+ last;
+ }
+ }
- # no need to do an if, it'll be empty if @pri_index is empty anyway
-
- my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
-
- my @const_rows;
-
- do { # no need to check anything at the front, we always want the first row
+ # since all we check here are the start of the order_by belonging to the
+ # top level $rsrc, a present identifying set will mean that the resultset
+ # is ordered by its leftmost table in a tsable manner
+ (@ord_cols and $rsrc->_identifying_column_set({ map
+ { $colinfos->{$_}{-colname} => $colinfos->{$_} }
+ @ord_cols
+ })) ? 1 : 0;
+ };
- my %const;
-
- foreach my $this_as (@construct_as) {
- $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
+ if ($attrs->{_ordered_for_collapse}) {
+ push @$rows, do { my @r = $cursor->next; @r ? \@r : () };
}
+ # instead of looping over ->next, use ->all in stealth mode
+ # *without* calling a ->reset afterwards
+ # FIXME - encapsulation breach, got to be a better way
+ elsif (! $cursor->{_done}) {
+ push @$rows, $cursor->all;
+ $cursor->{_done} = 1;
+ $fetch_all = 1;
+ }
+ }
- push(@const_rows, \%const);
-
- } until ( # no pri_index => no collapse => drop straight out
- !@pri_index
- or
- do { # get another row, stash it, drop out if different PK
-
- @copy = $self->cursor->next;
- $self->{stashed_row} = \@copy;
-
- # last thing in do block, counts as true if anything doesn't match
-
- # check xor defined first for NULL vs. NOT NULL then if one is
- # defined the other must be so check string equality
-
- grep {
- (defined $pri_vals{$_} ^ defined $copy[$_])
- || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
- } @pri_index;
- }
- );
+ return undef unless @$rows;
- my $alias = $self->{attrs}{alias};
- my $info = [];
+ my $res_class = $self->result_class;
+ my $inflator = $res_class->can ('inflate_result')
+ or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
- my %collapse_pos;
+ my $infmap = $attrs->{as};
- my @const_keys;
+ if (!$attrs->{collapse} and $attrs->{_single_object_inflation}) {
+ # construct a much simpler array->hash folder for the one-table cases right here
- foreach my $const (@const_rows) {
- scalar @const_keys or do {
- @const_keys = sort { length($a) <=> length($b) } keys %$const;
- };
- foreach my $key (@const_keys) {
- if (length $key) {
- my $target = $info;
- my @parts = split(/\./, $key);
- my $cur = '';
- my $data = $const->{$key};
- foreach my $p (@parts) {
- $target = $target->[1]->{$p} ||= [];
- $cur .= ".${p}";
- if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
- # collapsing at this point and on final part
- my $pos = $collapse_pos{$cur};
- CK: foreach my $ck (@ckey) {
- if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
- $collapse_pos{$cur} = $data;
- delete @collapse_pos{ # clear all positioning for sub-entries
- grep { m/^\Q${cur}.\E/ } keys %collapse_pos
- };
- push(@$target, []);
- last CK;
- }
- }
- }
- if (exists $collapse{$cur}) {
- $target = $target->[-1];
- }
- }
- $target->[0] = $data;
- } else {
- $info->[0] = $const->{$key};
+ # FIXME SUBOPTIMAL this is a very very very hot spot
+ # while rather optimal we can *still* do much better, by
+ # building a smarter [Row|HRI]::inflate_result(), and
+ # switch to feeding it data via a much leaner interface
+ #
+ # crude unscientific benchmarking indicated the shortcut eval is not worth it for
+ # this particular resultset size
+ if (@$rows < 60) {
+ my @as_idx = 0..$#$infmap;
+ for my $r (@$rows) {
+ $r = $inflator->($res_class, $rsrc, { map { $infmap->[$_] => $r->[$_] } @as_idx } );
}
}
+ else {
+ eval sprintf (
+ '$_ = $inflator->($res_class, $rsrc, { %s }) for @$rows',
+ join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap )
+ );
+ }
+ }
+ else {
+ $self->{_row_parser} ||= eval sprintf 'sub { %s }', $rsrc->_mk_row_parser({
+ inflate_map => $infmap,
+ selection => $attrs->{select},
+ collapse => $attrs->{collapse},
+ premultiplied => $attrs->{_main_source_premultiplied},
+ }) or die $@;
+
+ # modify $rows in-place, shrinking/extending as necessary
+ $self->{_row_parser}->($rows, $fetch_all ? () : (
+ # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
+ sub { my @r = $cursor->next or return; \@r }, # how the collapser gets more rows
+ ($self->{stashed_rows} = []), # where does it stuff excess
+ ));
+
+ $_ = $inflator->($res_class, $rsrc, @$_) for @$rows;
+ }
+
+ # CDBI compat stuff
+ if ($attrs->{record_filter}) {
+ $_ = $attrs->{record_filter}->($_) for @$rows;
}
- return $info;
+ return $rows;
}
=head2 result_source
=over 4
-=item Arguments: $result_source?
+=item Arguments: L<$result_source?|DBIx::Class::ResultSource>
-=item Return Value: $result_source
+=item Return Value: L<$result_source|DBIx::Class::ResultSource>
=back
=back
-An accessor for the class to use when creating row objects. Defaults to
-C<< result_source->result_class >> - which in most cases is the name of the
+An accessor for the class to use when creating result objects. Defaults to
+C<< result_source->result_class >> - which in most cases is the name of the
L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
+Note that changing the result_class will also remove any components
+that were originally loaded in the source class via
+L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
+in the original source class will not run.
+
=cut
+sub result_class {
+ my ($self, $result_class) = @_;
+ if ($result_class) {
+ unless (ref $result_class) { # don't fire this for an object
+ $self->ensure_class_loaded($result_class);
+ }
+ $self->_result_class($result_class);
+ # THIS LINE WOULD BE A BUG - this accessor specifically exists to
+ # permit the user to set result class on one result set only; it only
+ # chains if provided to search()
+ #$self->{attrs}{result_class} = $result_class if ref $self;
+ }
+ $self->_result_class;
+}
=head2 count
=over 4
-=item Arguments: $cond, \%attrs??
+=item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
=item Return Value: $count
=back
Performs an SQL C<COUNT> with the same query as the resultset was built
-with to find the number of elements. If passed arguments, does a search
-on the resultset and counts the results of that.
-
-Note: When using C<count> with C<group_by>, L<DBIx::Class> emulates C<GROUP BY>
-using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do
-not support C<DISTINCT> with multiple columns. If you are using such a
-database, you should only use columns from the main table in your C<group_by>
-clause.
+with to find the number of elements. Passing arguments is equivalent to
+C<< $rs->search ($cond, \%attrs)->count >>
=cut
my $self = shift;
return $self->search(@_)->count if @_ and defined $_[0];
return scalar @{ $self->get_cache } if $self->get_cache;
- my $count = $self->_count;
- return 0 unless $count;
- # need to take offset from resolved attrs
+ my $attrs = { %{ $self->_resolved_attrs } };
+
+ # this is a little optimization - it is faster to do the limit
+ # adjustments in software, instead of a subquery
+ my ($rows, $offset) = delete @{$attrs}{qw/rows offset/};
+
+ my $crs;
+ if ($self->_has_resolved_attr (qw/collapse group_by/)) {
+ $crs = $self->_count_subq_rs ($attrs);
+ }
+ else {
+ $crs = $self->_count_rs ($attrs);
+ }
+ my $count = $crs->next;
- $count -= $self->{_attrs}{offset} if $self->{_attrs}{offset};
- $count = $self->{attrs}{rows} if
- $self->{attrs}{rows} and $self->{attrs}{rows} < $count;
+ $count -= $offset if $offset;
+ $count = $rows if $rows and $rows < $count;
$count = 0 if ($count < 0);
+
return $count;
}
-sub _count { # Separated out so pager can get the full count
+=head2 count_rs
+
+=over 4
+
+=item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
+
+=item Return Value: L<$count_rs|DBIx::Class::ResultSetColumn>
+
+=back
+
+Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
+This can be very handy for subqueries:
+
+ ->search( { amount => $some_rs->count_rs->as_query } )
+
+As with regular resultsets the SQL query will be executed only after
+the resultset is accessed via L</next> or L</all>. That would return
+the same single value obtainable via L</count>.
+
+=cut
+
+sub count_rs {
my $self = shift;
- my $select = { count => '*' };
+ return $self->search(@_)->count_rs if @_;
+
+ # this may look like a lack of abstraction (count() does about the same)
+ # but in fact an _rs *must* use a subquery for the limits, as the
+ # software based limiting can not be ported if this $rs is to be used
+ # in a subquery itself (i.e. ->as_query)
+ if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
+ return $self->_count_subq_rs;
+ }
+ else {
+ return $self->_count_rs;
+ }
+}
- my $attrs = { %{$self->_resolved_attrs} };
- if (my $group_by = delete $attrs->{group_by}) {
- delete $attrs->{having};
- my @distinct = (ref $group_by ? @$group_by : ($group_by));
- # todo: try CONCAT for multi-column pk
- my @pk = $self->result_source->primary_columns;
- if (@pk == 1) {
- my $alias = $attrs->{alias};
- foreach my $column (@distinct) {
- if ($column =~ qr/^(?:\Q${alias}.\E)?$pk[0]$/) {
- @distinct = ($column);
- last;
+#
+# returns a ResultSetColumn object tied to the count query
+#
+sub _count_rs {
+ my ($self, $attrs) = @_;
+
+ my $rsrc = $self->result_source;
+ $attrs ||= $self->_resolved_attrs;
+
+ my $tmp_attrs = { %$attrs };
+ # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
+ delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
+
+ # overwrite the selector (supplied by the storage)
+ $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $attrs);
+ $tmp_attrs->{as} = 'count';
+
+ my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
+
+ return $tmp_rs;
+}
+
+#
+# same as above but uses a subquery
+#
+sub _count_subq_rs {
+ my ($self, $attrs) = @_;
+
+ my $rsrc = $self->result_source;
+ $attrs ||= $self->_resolved_attrs;
+
+ my $sub_attrs = { %$attrs };
+ # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
+ delete @{$sub_attrs}{qw/collapse columns as select _prefetch_selector_range order_by for/};
+
+ # if we multi-prefetch we group_by something unique, as this is what we would
+ # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
+ if ( $attrs->{collapse} ) {
+ $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
+ $rsrc->_identifying_column_set || $self->throw_exception(
+ 'Unable to construct a unique group_by criteria properly collapsing the '
+ . 'has_many prefetch before count()'
+ );
+ } ]
+ }
+
+ # Calculate subquery selector
+ if (my $g = $sub_attrs->{group_by}) {
+
+ my $sql_maker = $rsrc->storage->sql_maker;
+
+ # necessary as the group_by may refer to aliased functions
+ my $sel_index;
+ for my $sel (@{$attrs->{select}}) {
+ $sel_index->{$sel->{-as}} = $sel
+ if (ref $sel eq 'HASH' and $sel->{-as});
+ }
+
+ # anything from the original select mentioned on the group-by needs to make it to the inner selector
+ # also look for named aggregates referred in the having clause
+ # having often contains scalarrefs - thus parse it out entirely
+ my @parts = @$g;
+ if ($attrs->{having}) {
+ local $sql_maker->{having_bind};
+ local $sql_maker->{quote_char} = $sql_maker->{quote_char};
+ local $sql_maker->{name_sep} = $sql_maker->{name_sep};
+ unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
+ $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
+ # if we don't unset it we screw up retarded but unfortunately working
+ # 'MAX(foo.bar)' => { '>', 3 }
+ $sql_maker->{name_sep} = '';
+ }
+
+ my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
+
+ my $having_sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
+ my %seen_having;
+
+ # search for both a proper quoted qualified string, for a naive unquoted scalarref
+ # and if all fails for an utterly naive quoted scalar-with-function
+ while ($having_sql =~ /
+ $rquote $sep $lquote (.+?) $rquote
+ |
+ [\s,] \w+ \. (\w+) [\s,]
+ |
+ [\s,] $lquote (.+?) $rquote [\s,]
+ /gx) {
+ my $part = $1 || $2 || $3; # one of them matched if we got here
+ unless ($seen_having{$part}++) {
+ push @parts, $part;
}
}
}
- $select = { count => { distinct => \@distinct } };
- }
-
- $attrs->{select} = $select;
- $attrs->{as} = [qw/count/];
+ for (@parts) {
+ my $colpiece = $sel_index->{$_} || $_;
- # offset, order by and page are not needed to count. record_filter is cdbi
- delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/;
+ # unqualify join-based group_by's. Arcane but possible query
+ # also horrible horrible hack to alias a column (not a func.)
+ # (probably need to introduce SQLA syntax)
+ if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
+ my $as = $colpiece;
+ $as =~ s/\./__/;
+ $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
+ }
+ push @{$sub_attrs->{select}}, $colpiece;
+ }
+ }
+ else {
+ my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
+ $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
+ }
- my $tmp_rs = (ref $self)->new($self->result_source, $attrs);
- my ($count) = $tmp_rs->cursor->next;
- return $count;
+ return $rsrc->resultset_class
+ ->new ($rsrc, $sub_attrs)
+ ->as_subselect_rs
+ ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
+ ->get_column ('count');
}
sub _bool {
=head2 count_literal
+B<CAVEAT>: C<count_literal> is provided for Class::DBI compatibility and
+should only be used in that context. See L</search_literal> for further info.
+
=over 4
-=item Arguments: $sql_fragment, @bind_values
+=item Arguments: $sql_fragment, @standalone_bind_values
=item Return Value: $count
=item Arguments: none
-=item Return Value: @objects
+=item Return Value: L<@result_objs|DBIx::Class::Manual::ResultClass>
=back
-Returns all elements in the resultset. Called implicitly if the resultset
-is returned in list context.
+Returns all elements in the resultset.
=cut
sub all {
- my ($self) = @_;
- return @{ $self->get_cache } if $self->get_cache;
-
- my @obj;
-
- # TODO: don't call resolve here
- if (keys %{$self->_resolved_attrs->{collapse}}) {
-# if ($self->{attrs}{prefetch}) {
- # Using $self->cursor->all is really just an optimisation.
- # If we're collapsing has_many prefetches it probably makes
- # very little difference, and this is cleaner than hacking
- # _construct_object to survive the approach
- my @row = $self->cursor->next;
- while (@row) {
- push(@obj, $self->_construct_object(@row));
- @row = (exists $self->{stashed_row}
- ? @{delete $self->{stashed_row}}
- : $self->cursor->next);
- }
- } else {
- @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
+ my $self = shift;
+ if(@_) {
+ $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
+ }
+
+ delete @{$self}{qw/stashed_rows stashed_objects/};
+
+ if (my $c = $self->get_cache) {
+ return @$c;
}
- $self->set_cache(\@obj) if $self->{attrs}{cache};
- return @obj;
+ $self->cursor->reset;
+
+ my $objs = $self->_construct_objects('fetch_all') || [];
+
+ $self->set_cache($objs) if $self->{attrs}{cache};
+
+ return @$objs;
}
=head2 reset
=back
Resets the resultset's cursor, so you can iterate through the elements again.
+Implicitly resets the storage cursor, so a subsequent L</next> will trigger
+another query.
=cut
sub reset {
my ($self) = @_;
- delete $self->{_attrs} if exists $self->{_attrs};
+
+ delete @{$self}{qw/stashed_rows stashed_objects/};
$self->{all_cache_position} = 0;
$self->cursor->reset;
return $self;
=item Arguments: none
-=item Return Value: $object?
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
=back
-Resets the resultset and returns an object for the first result (if the
-resultset returns anything).
+L<Resets|/reset> the resultset (causing a fresh query to storage) and returns
+an object for the first result (or C<undef> if the resultset is empty).
=cut
return $_[0]->reset->next;
}
-# _cond_for_update_delete
+
+# _rs_update_delete
#
-# update/delete require the condition to be modified to handle
-# the differing SQL syntax available. This transforms the $self->{cond}
-# appropriately, returning the new condition.
-
-sub _cond_for_update_delete {
- my ($self, $full_cond) = @_;
- my $cond = {};
-
- $full_cond ||= $self->{cond};
- # No-op. No condition, we're updating/deleting everything
- return $cond unless ref $full_cond;
-
- if (ref $full_cond eq 'ARRAY') {
- $cond = [
- map {
- my %hash;
- foreach my $key (keys %{$_}) {
- $key =~ /([^.]+)$/;
- $hash{$1} = $_->{$key};
- }
- \%hash;
- } @{$full_cond}
- ];
+# Determines whether and what type of subquery is required for the $rs operation.
+# If grouping is necessary either supplies its own, or verifies the current one
+# After all is done delegates to the proper storage method.
+
+sub _rs_update_delete {
+ my ($self, $op, $values) = @_;
+
+ my $rsrc = $self->result_source;
+ my $storage = $rsrc->schema->storage;
+
+ my $attrs = { %{$self->_resolved_attrs} };
+
+ my $join_classifications;
+ my $existing_group_by = delete $attrs->{group_by};
+
+ # do we need a subquery for any reason?
+ my $needs_subq = (
+ defined $existing_group_by
+ or
+ # if {from} is unparseable wrap a subq
+ ref($attrs->{from}) ne 'ARRAY'
+ or
+ # limits call for a subq
+ $self->_has_resolved_attr(qw/rows offset/)
+ );
+
+ # simplify the joinmap, so we can further decide if a subq is necessary
+ if (!$needs_subq and @{$attrs->{from}} > 1) {
+ $attrs->{from} = $storage->_prune_unused_joins ($attrs->{from}, $attrs->{select}, $self->{cond}, $attrs);
+
+ # check if there are any joins left after the prune
+ if ( @{$attrs->{from}} > 1 ) {
+ $join_classifications = $storage->_resolve_aliastypes_from_select_args (
+ [ @{$attrs->{from}}[1 .. $#{$attrs->{from}}] ],
+ $attrs->{select},
+ $self->{cond},
+ $attrs
+ );
+
+ # any non-pruneable joins imply subq
+ $needs_subq = scalar keys %{ $join_classifications->{restricting} || {} };
+ }
}
- elsif (ref $full_cond eq 'HASH') {
- if ((keys %{$full_cond})[0] eq '-and') {
- $cond->{-and} = [];
- my @cond = @{$full_cond->{-and}};
- for (my $i = 0; $i < @cond; $i++) {
- my $entry = $cond[$i];
+ # check if the head is composite (by now all joins are thrown out unless $needs_subq)
+ $needs_subq ||= (
+ (ref $attrs->{from}[0]) ne 'HASH'
+ or
+ ref $attrs->{from}[0]{ $attrs->{from}[0]{-alias} }
+ );
- my $hash;
- if (ref $entry eq 'HASH') {
- $hash = $self->_cond_for_update_delete($entry);
- }
- else {
- $entry =~ /([^.]+)$/;
- $hash->{$1} = $cond[++$i];
- }
+ my ($cond, $guard);
+ # do we need anything like a subquery?
+ if (! $needs_subq) {
+ # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
+ # a condition containing 'me' or other table prefixes will not work
+ # at all. Tell SQLMaker to dequalify idents via a gross hack.
+ $cond = do {
+ my $sqla = $rsrc->storage->sql_maker;
+ local $sqla->{_dequalify_idents} = 1;
+ \[ $sqla->_recurse_where($self->{cond}) ];
+ };
+ }
+ else {
+ # we got this far - means it is time to wrap a subquery
+ my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
+ sprintf(
+ "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
+ $op,
+ $rsrc->source_name,
+ )
+ );
- push @{$cond->{-and}}, $hash;
- }
+ # make a new $rs selecting only the PKs (that's all we really need for the subq)
+ delete $attrs->{$_} for qw/collapse select _prefetch_selector_range as/;
+ $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
+ $attrs->{group_by} = \ ''; # FIXME - this is an evil hack, it causes the optimiser to kick in and throw away the LEFT joins
+ my $subrs = (ref $self)->new($rsrc, $attrs);
+
+ if (@$idcols == 1) {
+ $cond = { $idcols->[0] => { -in => $subrs->as_query } };
+ }
+ elsif ($storage->_use_multicolumn_in) {
+ # no syntax for calling this properly yet
+ # !!! EXPERIMENTAL API !!! WILL CHANGE !!!
+ $cond = $storage->sql_maker->_where_op_multicolumn_in (
+ $idcols, # how do I convey a list of idents...? can binds reside on lhs?
+ $subrs->as_query
+ ),
}
else {
- foreach my $key (keys %{$full_cond}) {
- $key =~ /([^.]+)$/;
- $cond->{$1} = $full_cond->{$key};
+ # if all else fails - get all primary keys and operate over a ORed set
+ # wrap in a transaction for consistency
+ # this is where the group_by/multiplication starts to matter
+ if (
+ $existing_group_by
+ or
+ keys %{ $join_classifications->{multiplying} || {} }
+ ) {
+ # make sure if there is a supplied group_by it matches the columns compiled above
+ # perfectly. Anything else can not be sanely executed on most databases so croak
+ # right then and there
+ if ($existing_group_by) {
+ my @current_group_by = map
+ { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
+ @$existing_group_by
+ ;
+
+ if (
+ join ("\x00", sort @current_group_by)
+ ne
+ join ("\x00", sort @{$attrs->{columns}} )
+ ) {
+ $self->throw_exception (
+ "You have just attempted a $op operation on a resultset which does group_by"
+ . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
+ . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
+ . ' kind of queries. Please retry the operation with a modified group_by or'
+ . ' without using one at all.'
+ );
+ }
+ }
+
+ $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
+ }
+
+ $guard = $storage->txn_scope_guard;
+
+ $cond = [];
+ for my $row ($subrs->cursor->all) {
+ push @$cond, { map
+ { $idcols->[$_] => $row->[$_] }
+ (0 .. $#$idcols)
+ };
}
}
}
- else {
- $self->throw_exception(
- "Can't update/delete on resultset with condition unless hash or array"
- );
- }
- return $cond;
-}
+ my $res = $storage->$op (
+ $rsrc,
+ $op eq 'update' ? $values : (),
+ $cond,
+ );
+
+ $guard->commit if $guard;
+ return $res;
+}
=head2 update
=item Arguments: \%values
-=item Return Value: $storage_rv
+=item Return Value: $underlying_storage_rv
=back
Sets the specified columns in the resultset to the supplied values in a
-single query. Return value will be true if the update succeeded or false
-if no records were updated; exact type of success value is storage-dependent.
+single query. Note that this will not run any accessor/set_column/update
+triggers, nor will it update any result object instances derived from this
+resultset (this includes the contents of the L<resultset cache|/set_cache>
+if any). See L</update_all> if you need to execute any on-update
+triggers or cascades defined either by you or a
+L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
+
+The return value is a pass through of what the underlying
+storage backend returned, and may vary. See L<DBI/execute> for the most
+common case.
+
+=head3 CAVEAT
+
+Note that L</update> does not process/deflate any of the values passed in.
+This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
+ensure manually that any value passed to this method will stringify to
+something the RDBMS knows how to deal with. A notable example is the
+handling of L<DateTime> objects, for more info see:
+L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
=cut
sub update {
my ($self, $values) = @_;
- $self->throw_exception("Values for update must be a hash")
+ $self->throw_exception('Values for update must be a hash')
unless ref $values eq 'HASH';
- my $cond = $self->_cond_for_update_delete;
-
- return $self->result_source->storage->update(
- $self->result_source, $values, $cond
- );
+ return $self->_rs_update_delete ('update', $values);
}
=head2 update_all
=back
-Fetches all objects and updates them one at a time. Note that C<update_all>
-will run DBIC cascade triggers, while L</update> will not.
+Fetches all objects and updates them one at a time via
+L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
+triggers, while L</update> will not.
=cut
sub update_all {
my ($self, $values) = @_;
- $self->throw_exception("Values for update must be a hash")
+ $self->throw_exception('Values for update_all must be a hash')
unless ref $values eq 'HASH';
- foreach my $obj ($self->all) {
- $obj->set_columns($values)->update;
- }
+
+ my $guard = $self->result_source->schema->txn_scope_guard;
+ $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
+ $guard->commit;
return 1;
}
=item Arguments: none
-=item Return Value: 1
+=item Return Value: $underlying_storage_rv
=back
-Deletes the contents of the resultset from its result source. Note that this
-will not run DBIC cascade triggers. See L</delete_all> if you need triggers
-to run. See also L<DBIx::Class::Row/delete>.
+Deletes the rows matching this resultset in a single query. Note that this
+will not run any delete triggers, nor will it alter the
+L<in_storage|DBIx::Class::Row/in_storage> status of any result object instances
+derived from this resultset (this includes the contents of the
+L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
+execute any on-delete triggers or cascades defined either by you or a
+L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
+
+The return value is a pass through of what the underlying storage backend
+returned, and may vary. See L<DBI/execute> for the most common case.
=cut
sub delete {
- my ($self) = @_;
-
- my $cond = $self->_cond_for_update_delete;
+ my $self = shift;
+ $self->throw_exception('delete does not accept any arguments')
+ if @_;
- $self->result_source->storage->delete($self->result_source, $cond);
- return 1;
+ return $self->_rs_update_delete ('delete');
}
=head2 delete_all
=back
-Fetches all objects and deletes them one at a time. Note that C<delete_all>
-will run DBIC cascade triggers, while L</delete> will not.
+Fetches all objects and deletes them one at a time via
+L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
+triggers, while L</delete> will not.
=cut
sub delete_all {
- my ($self) = @_;
+ my $self = shift;
+ $self->throw_exception('delete_all does not accept any arguments')
+ if @_;
+
+ my $guard = $self->result_source->schema->txn_scope_guard;
$_->delete for $self->all;
+ $guard->commit;
return 1;
}
=over 4
-=item Arguments: \@data;
+=item Arguments: [ \@column_list, \@row_values+ ] | [ \%col_data+ ]
+
+=item Return Value: L<\@result_objects|DBIx::Class::Manual::ResultClass> (scalar context) | L<@result_objects|DBIx::Class::Manual::ResultClass> (list context)
+
+=back
+
+Accepts either an arrayref of hashrefs or alternatively an arrayref of
+arrayrefs.
+
+=over
+
+=item NOTE
+
+The context of this method call has an important effect on what is
+submitted to storage. In void context data is fed directly to fastpath
+insertion routines provided by the underlying storage (most often
+L<DBI/execute_for_fetch>), bypassing the L<new|DBIx::Class::Row/new> and
+L<insert|DBIx::Class::Row/insert> calls on the
+L<Result|DBIx::Class::Manual::ResultClass> class, including any
+augmentation of these methods provided by components. For example if you
+are using something like L<DBIx::Class::UUIDColumns> to create primary
+keys for you, you will find that your PKs are empty. In this case you
+will have to explicitly force scalar or list context in order to create
+those values.
=back
-Pass an arrayref of hashrefs. Each hashref should be a structure suitable for
-submitting to a $resultset->create(...) method.
+In non-void (scalar or list) context, this method is simply a wrapper
+for L</create>. Depending on list or scalar context either a list of
+L<Result|DBIx::Class::Manual::ResultClass> objects or an arrayref
+containing these objects is returned.
-In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
-to insert the data, as this is a faster method.
+When supplying data in "arrayref of arrayrefs" invocation style, the
+first element should be a list of column names and each subsequent
+element should be a data value in the earlier specified column order.
+For example:
-Otherwise, each set of data is inserted into the database using
-L<DBIx::Class::ResultSet/create>, and a arrayref of the resulting row
-objects is returned.
+ $Arstist_rs->populate([
+ [ qw( artistid name ) ],
+ [ 100, 'A Formally Unknown Singer' ],
+ [ 101, 'A singer that jumped the shark two albums ago' ],
+ [ 102, 'An actually cool singer' ],
+ ]);
-Example: Assuming an Artist Class that has many CDs Classes relating:
+For the arrayref of hashrefs style each hashref should be a structure
+suitable for passing to L</create>. Multi-create is also permitted with
+this syntax.
- my $Artist_rs = $schema->resultset("Artist");
-
- ## Void Context Example
- $Artist_rs->populate([
- { artistid => 4, name => 'Manufactured Crap', cds => [
+ $schema->resultset("Artist")->populate([
+ { artistid => 4, name => 'Manufactured Crap', cds => [
{ title => 'My First CD', year => 2006 },
{ title => 'Yet More Tweeny-Pop crap', year => 2007 },
],
},
{ artistid => 5, name => 'Angsty-Whiny Girl', cds => [
- { title => 'My parents sold me to a record company' ,year => 2005 },
+ { title => 'My parents sold me to a record company', year => 2005 },
{ title => 'Why Am I So Ugly?', year => 2006 },
{ title => 'I Got Surgery and am now Popular', year => 2007 }
],
},
]);
-
- ## Array Context Example
- my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
- { name => "Artist One"},
- { name => "Artist Two"},
- { name => "Artist Three", cds=> [
- { title => "First CD", year => 2007},
- { title => "Second CD", year => 2008},
- ]}
- ]);
-
- print $ArtistOne->name; ## response is 'Artist One'
- print $ArtistThree->cds->count ## reponse is '2'
-
-Please note an important effect on your data when choosing between void and
-wantarray context. Since void context goes straight to C<insert_bulk> in
-L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
-c<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
-create primary keys for you, you will find that your PKs are empty. In this
-case you will have to use the wantarray context in order to create those
-values.
+
+If you attempt a void-context multi-create as in the example above (each
+Artist also has the related list of CDs), and B<do not> supply the
+necessary autoinc foreign key information, this method will proxy to the
+less efficient L</create>, and then throw the Result objects away. In this
+case there are obviously no benefits to using this method over L</create>.
=cut
sub populate {
- my ($self, $data) = @_;
-
+ my $self = shift;
+
+ # cruft placed in standalone method
+ my $data = $self->_normalize_populate_args(@_);
+
+ return unless @$data;
+
if(defined wantarray) {
- my @created;
- foreach my $item (@$data) {
- push(@created, $self->create($item));
+ my @created = map { $self->create($_) } @$data;
+ return wantarray ? @created : \@created;
+ }
+ else {
+ my $first = $data->[0];
+
+ # if a column is a registered relationship, and is a non-blessed hash/array, consider
+ # it relationship data
+ my (@rels, @columns);
+ my $rsrc = $self->result_source;
+ my $rels = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
+ for (keys %$first) {
+ my $ref = ref $first->{$_};
+ $rels->{$_} && ($ref eq 'ARRAY' or $ref eq 'HASH')
+ ? push @rels, $_
+ : push @columns, $_
+ ;
}
- return @created;
- } else {
- my ($first, @rest) = @$data;
- my @names = grep {!ref $first->{$_}} keys %$first;
- my @rels = grep { $self->result_source->has_relationship($_) } keys %$first;
- my @pks = $self->result_source->primary_columns;
+ my @pks = $rsrc->primary_columns;
- ## do the belongs_to relationships
+ ## do the belongs_to relationships
foreach my $index (0..$#$data) {
- if( grep { !defined $data->[$index]->{$_} } @pks ) {
- my @ret = $self->populate($data);
- return;
+
+ # delegate to create() for any dataset without primary keys with specified relationships
+ if (grep { !defined $data->[$index]->{$_} } @pks ) {
+ for my $r (@rels) {
+ if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
+ my @ret = $self->populate($data);
+ return;
+ }
+ }
}
-
+
foreach my $rel (@rels) {
- next unless $data->[$index]->{$rel} && ref $data->[$index]->{$rel} eq "HASH";
+ next unless ref $data->[$index]->{$rel} eq "HASH";
my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
- my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
- my $related = $result->result_source->resolve_condition(
- $result->result_source->relationship_info($reverse)->{cond},
- $self,
- $result,
+ my ($reverse_relname, $reverse_relinfo) = %{$rsrc->reverse_relationship_info($rel)};
+ my $related = $result->result_source->_resolve_condition(
+ $reverse_relinfo->{cond},
+ $self,
+ $result,
+ $rel,
);
delete $data->[$index]->{$rel};
$data->[$index] = {%{$data->[$index]}, %$related};
-
- push @names, keys %$related if $index == 0;
+
+ push @columns, keys %$related if $index == 0;
}
}
- ## do bulk insert on current row
- my @values = map { [ @$_{@names} ] } @$data;
+ ## inherit the data locked in the conditions of the resultset
+ my ($rs_data) = $self->_merge_with_rscond({});
+ delete @{$rs_data}{@columns};
- $self->result_source->storage->insert_bulk(
- $self->result_source,
- \@names,
- \@values,
+ ## do bulk insert on current row
+ $rsrc->storage->insert_bulk(
+ $rsrc,
+ [@columns, keys %$rs_data],
+ [ map { [ @$_{@columns}, values %$rs_data ] } @$data ],
);
## do the has_many relationships
foreach my $item (@$data) {
+ my $main_row;
+
foreach my $rel (@rels) {
- next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
-
- my $parent = $self->find(map {{$_=>$item->{$_}} } @pks)
- || $self->throw_exception('Cannot find the relating object.');
-
- my $child = $parent->$rel;
-
- my $related = $child->result_source->resolve_condition(
- $parent->result_source->relationship_info($rel)->{cond},
+ next unless ref $item->{$rel} eq "ARRAY" && @{ $item->{$rel} };
+
+ $main_row ||= $self->new_result({map { $_ => $item->{$_} } @pks});
+
+ my $child = $main_row->$rel;
+
+ my $related = $child->result_source->_resolve_condition(
+ $rels->{$rel}{cond},
$child,
- $parent,
+ $main_row,
+ $rel,
);
my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
}
}
+
+# populate() argumnets went over several incarnations
+# What we ultimately support is AoH
+sub _normalize_populate_args {
+ my ($self, $arg) = @_;
+
+ if (ref $arg eq 'ARRAY') {
+ if (!@$arg) {
+ return [];
+ }
+ elsif (ref $arg->[0] eq 'HASH') {
+ return $arg;
+ }
+ elsif (ref $arg->[0] eq 'ARRAY') {
+ my @ret;
+ my @colnames = @{$arg->[0]};
+ foreach my $values (@{$arg}[1 .. $#$arg]) {
+ push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
+ }
+ return \@ret;
+ }
+ }
+
+ $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
+}
+
=head2 pager
=over 4
=item Arguments: none
-=item Return Value: $pager
+=item Return Value: L<$pager|Data::Page>
=back
-Return Value a L<Data::Page> object for the current resultset. Only makes
+Returns a L<Data::Page> object for the current resultset. Only makes
sense for queries with a C<page> attribute.
+To get the full count of entries for a paged resultset, call
+C<total_entries> on the L<Data::Page> object.
+
=cut
sub pager {
my ($self) = @_;
+
+ return $self->{pager} if $self->{pager};
+
my $attrs = $self->{attrs};
- $self->throw_exception("Can't create pager for non-paged rs")
- unless $self->{attrs}{page};
+ if (!defined $attrs->{page}) {
+ $self->throw_exception("Can't create pager for non-paged rs");
+ }
+ elsif ($attrs->{page} <= 0) {
+ $self->throw_exception('Invalid page number (page-numbers are 1-based)');
+ }
$attrs->{rows} ||= 10;
- return $self->{pager} ||= Data::Page->new(
- $self->_count, $attrs->{rows}, $self->{attrs}{page});
+
+ # throw away the paging flags and re-run the count (possibly
+ # with a subselect) to get the real total count
+ my $count_attrs = { %$attrs };
+ delete @{$count_attrs}{qw/rows offset page pager/};
+
+ my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
+
+ require DBIx::Class::ResultSet::Pager;
+ return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
+ sub { $total_rs->count }, #lazy-get the total
+ $attrs->{rows},
+ $self->{attrs}{page},
+ );
}
=head2 page
=item Arguments: $page_number
-=item Return Value: $rs
+=item Return Value: L<$resultset|/search>
=back
=over 4
-=item Arguments: \%vals
+=item Arguments: \%col_data
-=item Return Value: $object
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
=back
-Creates a new row object in the resultset's result class and returns
+Creates a new result object in the resultset's result class and returns
it. The row is not inserted into the database at this point, call
L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
-will tell you whether the row object has been inserted or not.
+will tell you whether the result object has been inserted or not.
Passes the hashref of input on to L<DBIx::Class::Row/new>.
sub new_result {
my ($self, $values) = @_;
- $self->throw_exception( "new_result needs a hash" )
+
+ $self->throw_exception( "new_result takes only one argument - a hashref of values" )
+ if @_ > 2;
+
+ $self->throw_exception( "new_result expects a hashref" )
unless (ref $values eq 'HASH');
- $self->throw_exception(
- "Implicit construct invalid, condition was not resolveable on parent "
- ."object"
- ) if (defined $self->{cond}
- && $self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION);
- $self->throw_exception(
- "Can't abstract implicit construct, condition not a hash"
- ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
- my $alias = $self->{attrs}{alias};
- my $collapsed_cond = $self->{cond} ? $self->_collapse_cond($self->{cond}) : {};
-
- # precendence must be given to passed values over values inherited from the cond,
- # so the order here is important.
- my %new;
- my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
- while( my($col,$value) = each %implied ){
- if(ref($value) eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '='){
- $new{$col} = $value->{'='};
- next;
- }
- $new{$col} = $value if $self->_is_deterministic_value($value);
- }
+ my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
- %new = (
- %new,
- %{ $self->_remove_alias($values, $alias) },
- -source_handle => $self->_source_handle,
+ my %new = (
+ %$merged_cond,
+ @$cols_from_relations
+ ? (-cols_from_relations => $cols_from_relations)
+ : (),
-result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
);
return $self->result_class->new(\%new);
}
-# _is_deterministic_value
+# _merge_with_rscond
#
-# Make an effor to strip non-deterministic values from the condition,
-# to make sure new_result chokes less
+# Takes a simple hash of K/V data and returns its copy merged with the
+# condition already present on the resultset. Additionally returns an
+# arrayref of value/condition names, which were inferred from related
+# objects (this is needed for in-memory related objects)
+sub _merge_with_rscond {
+ my ($self, $data) = @_;
-sub _is_deterministic_value {
- my $self = shift;
- my $value = shift;
- my $ref_type = ref $value;
- return 1 if $ref_type eq '' || $ref_type eq 'SCALAR';
- return 1 if Scalar::Util::blessed($value);
- return 0;
+ my (%new_data, @cols_from_relations);
+
+ my $alias = $self->{attrs}{alias};
+
+ if (! defined $self->{cond}) {
+ # just massage $data below
+ }
+ elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
+ %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
+ @cols_from_relations = keys %new_data;
+ }
+ elsif (ref $self->{cond} ne 'HASH') {
+ $self->throw_exception(
+ "Can't abstract implicit construct, resultset condition not a hash"
+ );
+ }
+ else {
+ # precendence must be given to passed values over values inherited from
+ # the cond, so the order here is important.
+ my $collapsed_cond = $self->_collapse_cond($self->{cond});
+ my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
+
+ while ( my($col, $value) = each %implied ) {
+ my $vref = ref $value;
+ if (
+ $vref eq 'HASH'
+ and
+ keys(%$value) == 1
+ and
+ (keys %$value)[0] eq '='
+ ) {
+ $new_data{$col} = $value->{'='};
+ }
+ elsif( !$vref or $vref eq 'SCALAR' or blessed($value) ) {
+ $new_data{$col} = $value;
+ }
+ }
+ }
+
+ %new_data = (
+ %new_data,
+ %{ $self->_remove_alias($data, $alias) },
+ );
+
+ return (\%new_data, \@cols_from_relations);
+}
+
+# _has_resolved_attr
+#
+# determines if the resultset defines at least one
+# of the attributes supplied
+#
+# used to determine if a subquery is neccessary
+#
+# supports some virtual attributes:
+# -join
+# This will scan for any joins being present on the resultset.
+# It is not a mere key-search but a deep inspection of {from}
+#
+
+sub _has_resolved_attr {
+ my ($self, @attr_names) = @_;
+
+ my $attrs = $self->_resolved_attrs;
+
+ my %extra_checks;
+
+ for my $n (@attr_names) {
+ if (grep { $n eq $_ } (qw/-join/) ) {
+ $extra_checks{$n}++;
+ next;
+ }
+
+ my $attr = $attrs->{$n};
+
+ next if not defined $attr;
+
+ if (ref $attr eq 'HASH') {
+ return 1 if keys %$attr;
+ }
+ elsif (ref $attr eq 'ARRAY') {
+ return 1 if @$attr;
+ }
+ else {
+ return 1 if $attr;
+ }
+ }
+
+ # a resolved join is expressed as a multi-level from
+ return 1 if (
+ $extra_checks{-join}
+ and
+ ref $attrs->{from} eq 'ARRAY'
+ and
+ @{$attrs->{from}} > 1
+ );
+
+ return 0;
}
# _collapse_cond
if (ref $cond eq 'ARRAY') {
foreach my $subcond (@$cond) {
next unless ref $subcond; # -or
-# warn "ARRAY: " . Dumper $subcond;
$collapsed = $self->_collapse_cond($subcond, $collapsed);
}
}
elsif (ref $cond eq 'HASH') {
if (keys %$cond and (keys %$cond)[0] eq '-and') {
foreach my $subcond (@{$cond->{-and}}) {
-# warn "HASH: " . Dumper $subcond;
$collapsed = $self->_collapse_cond($subcond, $collapsed);
}
}
else {
-# warn "LEAF: " . Dumper $cond;
foreach my $col (keys %$cond) {
my $value = $cond->{$col};
$collapsed->{$col} = $value;
return \%unaliased;
}
+=head2 as_query
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
+
+=back
+
+Returns the SQL query and bind vars associated with the invocant.
+
+This is generally used as the RHS for a subquery.
+
+=cut
+
+sub as_query {
+ my $self = shift;
+
+ my $attrs = { %{ $self->_resolved_attrs } };
+
+ # For future use:
+ #
+ # in list ctx:
+ # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
+ # $sql also has no wrapping parenthesis in list ctx
+ #
+ my $sqlbind = $self->result_source->storage
+ ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
+
+ return $sqlbind;
+}
+
=head2 find_or_new
=over 4
-=item Arguments: \%vals, \%attrs?
+=item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
-=item Return Value: $object
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
=back
-Find an existing record from this resultset. If none exists, instantiate a new
-result object and return it. The object will not be saved into your storage
-until you call L<DBIx::Class::Row/insert> on it.
+ my $artist = $schema->resultset('Artist')->find_or_new(
+ { artist => 'fred' }, { key => 'artists' });
+
+ $cd->cd_to_producer->find_or_new({ producer => $producer },
+ { key => 'primary });
+
+Find an existing record from this resultset using L</find>. if none exists,
+instantiate a new result object and return it. The object will not be saved
+into your storage until you call L<DBIx::Class::Row/insert> on it.
+
+You most likely want this method when looking for existing rows using a unique
+constraint that is not the primary key, or looking for related rows.
If you want objects to be saved immediately, use L</find_or_create> instead.
+B<Note>: Make sure to read the documentation of L</find> and understand the
+significance of the C<key> attribute, as its lack may skew your search, and
+subsequently result in spurious new objects.
+
+B<Note>: Take care when using C<find_or_new> with a table having
+columns with default values that you intend to be automatically
+supplied by the database (e.g. an auto_increment primary key column).
+In normal usage, the value of such columns should NOT be included at
+all in the call to C<find_or_new>, even when set to C<undef>.
+
=cut
sub find_or_new {
my $self = shift;
my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
- my $exists = $self->find($hash, $attrs);
- return defined $exists ? $exists : $self->new_result($hash);
+ if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
+ return $row;
+ }
+ return $self->new_result($hash);
}
=head2 create
=over 4
-=item Arguments: \%vals
+=item Arguments: \%col_data
-=item Return Value: a L<DBIx::Class::Row> $object
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
=back
pairs representing the columns of the table and the values you wish to
store. If the appropriate relationships are set up, foreign key fields
can also be passed an object representing the foreign row, and the
-value will be set to it's primary key.
+value will be set to its primary key.
-To create related objects, pass a hashref for the value if the related
-item is a foreign key relationship (L<DBIx::Class::Relationship/belongs_to>),
-and use the name of the relationship as the key. (NOT the name of the field,
-necessarily). For C<has_many> and C<has_one> relationships, pass an arrayref
-of hashrefs containing the data for each of the rows to create in the foreign
-tables, again using the relationship name as the key.
+To create related objects, pass a hashref of related-object column values
+B<keyed on the relationship name>. If the relationship is of type C<multi>
+(L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
+The process will correctly identify columns holding foreign keys, and will
+transparently populate them from the keys of the corresponding relation.
+This can be applied recursively, and will work correctly for a structure
+with an arbitrary depth and width, as long as the relationships actually
+exists and the correct column data has been supplied.
Instead of hashrefs of plain related data (key/value pairs), you may
also pass new or inserted objects. New objects (not inserted yet, see
-L</new>), will be inserted into their appropriate tables.
+L</new_result>), will be inserted into their appropriate tables.
-Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
+Effectively a shortcut for C<< ->new_result(\%col_data)->insert >>.
Example of creating a new row.
$person_rs->create({
name=>"Some Person",
- email=>"somebody@someplace.com"
+ email=>"somebody@someplace.com"
});
-
+
Example of creating a new row and also creating rows in a related C<has_many>
or C<has_one> resultset. Note Arrayref.
$artist_rs->create(
- { artistid => 4, name => 'Manufactured Crap', cds => [
+ { artistid => 4, name => 'Manufactured Crap', cds => [
{ title => 'My First CD', year => 2006 },
{ title => 'Yet More Tweeny-Pop crap', year => 2007 },
],
);
Example of creating a new row and also creating a row in a related
-C<belongs_to>resultset. Note Hashref.
+C<belongs_to> resultset. Note Hashref.
$cd_rs->create({
title=>"Music for Silly Walks",
- year=>2000,
- artist => {
- name=>"Silly Musician",
- }
+ year=>2000,
+ artist => {
+ name=>"Silly Musician",
+ }
});
+=over
+
+=item WARNING
+
+When subclassing ResultSet never attempt to override this method. Since
+it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
+lot of the internals simply never call it, so your override will be
+bypassed more often than not. Override either L<DBIx::Class::Row/new>
+or L<DBIx::Class::Row/insert> depending on how early in the
+L</create> process you need to intervene. See also warning pertaining to
+L</new>.
+
+=back
+
=cut
sub create {
=over 4
-=item Arguments: \%vals, \%attrs?
+=item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
-=item Return Value: $object
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
=back
- $class->find_or_create({ key => $val, ... });
+ $cd->cd_to_producer->find_or_create({ producer => $producer },
+ { key => 'primary' });
-Tries to find a record based on its primary key or unique constraint; if none
+Tries to find a record based on its primary key or unique constraints; if none
is found, creates one and returns that instead.
my $cd = $schema->resultset('CD')->find_or_create({
{ key => 'cd_artist_title' }
);
-Note: Because find_or_create() reads from the database and then
+B<Note>: Make sure to read the documentation of L</find> and understand the
+significance of the C<key> attribute, as its lack may skew your search, and
+subsequently result in spurious row creation.
+
+B<Note>: Because find_or_create() reads from the database and then
possibly inserts based on the result, this method is subject to a race
condition. Another process could create a record in the table after
the find has completed and before the create has started. To avoid
this problem, use find_or_create() inside a transaction.
+B<Note>: Take care when using C<find_or_create> with a table having
+columns with default values that you intend to be automatically
+supplied by the database (e.g. an auto_increment primary key column).
+In normal usage, the value of such columns should NOT be included at
+all in the call to C<find_or_create>, even when set to C<undef>.
+
See also L</find> and L</update_or_create>. For information on how to declare
unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
+If you need to know if an existing row was found or a new one created use
+L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
+to call L<DBIx::Class::Row/insert> to save the newly created row to the
+database!
+
+ my $cd = $schema->resultset('CD')->find_or_new({
+ cdid => 5,
+ artist => 'Massive Attack',
+ title => 'Mezzanine',
+ year => 2005,
+ });
+
+ if( !$cd->in_storage ) {
+ # do some stuff
+ $cd->insert;
+ }
+
=cut
sub find_or_create {
my $self = shift;
my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
- my $exists = $self->find($hash, $attrs);
- return defined $exists ? $exists : $self->create($hash);
+ if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
+ return $row;
+ }
+ return $self->create($hash);
}
=head2 update_or_create
=over 4
-=item Arguments: \%col_values, { key => $unique_constraint }?
+=item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
-=item Return Value: $object
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
=back
- $class->update_or_create({ col => $val, ... });
+ $resultset->update_or_create({ col => $val, ... });
+
+Like L</find_or_create>, but if a row is found it is immediately updated via
+C<< $found_row->update (\%col_data) >>.
-First, searches for an existing row matching one of the unique constraints
-(including the primary key) on the source of this resultset. If a row is
-found, updates it with the other given column values. Otherwise, creates a new
-row.
Takes an optional C<key> attribute to search on a specific unique constraint.
For example:
{ key => 'cd_artist_title' }
);
-If no C<key> is specified, it searches on all unique constraints defined on the
-source, including the primary key.
+ $cd->cd_to_producer->update_or_create({
+ producer => $producer,
+ name => 'harry',
+ }, {
+ key => 'primary',
+ });
-If the C<key> is specified as C<primary>, it searches only on the primary key.
+B<Note>: Make sure to read the documentation of L</find> and understand the
+significance of the C<key> attribute, as its lack may skew your search, and
+subsequently result in spurious row creation.
+
+B<Note>: Take care when using C<update_or_create> with a table having
+columns with default values that you intend to be automatically
+supplied by the database (e.g. an auto_increment primary key column).
+In normal usage, the value of such columns should NOT be included at
+all in the call to C<update_or_create>, even when set to C<undef>.
See also L</find> and L</find_or_create>. For information on how to declare
unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
+If you need to know if an existing row was updated or a new one created use
+L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
+to call L<DBIx::Class::Row/insert> to save the newly created row to the
+database!
+
=cut
sub update_or_create {
return $self->create($cond);
}
+=head2 update_or_new
+
+=over 4
+
+=item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
+
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
+
+=back
+
+ $resultset->update_or_new({ col => $val, ... });
+
+Like L</find_or_new> but if a row is found it is immediately updated via
+C<< $found_row->update (\%col_data) >>.
+
+For example:
+
+ # In your application
+ my $cd = $schema->resultset('CD')->update_or_new(
+ {
+ artist => 'Massive Attack',
+ title => 'Mezzanine',
+ year => 1998,
+ },
+ { key => 'cd_artist_title' }
+ );
+
+ if ($cd->in_storage) {
+ # the cd was updated
+ }
+ else {
+ # the cd is not yet in the database, let's insert it
+ $cd->insert;
+ }
+
+B<Note>: Make sure to read the documentation of L</find> and understand the
+significance of the C<key> attribute, as its lack may skew your search, and
+subsequently result in spurious new objects.
+
+B<Note>: Take care when using C<update_or_new> with a table having
+columns with default values that you intend to be automatically
+supplied by the database (e.g. an auto_increment primary key column).
+In normal usage, the value of such columns should NOT be included at
+all in the call to C<update_or_new>, even when set to C<undef>.
+
+See also L</find>, L</find_or_create> and L</find_or_new>.
+
+=cut
+
+sub update_or_new {
+ my $self = shift;
+ my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
+ my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
+
+ my $row = $self->find( $cond, $attrs );
+ if ( defined $row ) {
+ $row->update($cond);
+ return $row;
+ }
+
+ return $self->new_result($cond);
+}
+
=head2 get_cache
=over 4
=item Arguments: none
-=item Return Value: \@cache_objects?
+=item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass> | undef
=back
=over 4
-=item Arguments: \@cache_objects
+=item Arguments: L<\@result_objs|DBIx::Class::Manual::ResultClass>
-=item Return Value: \@cache_objects
+=item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass>
=back
Sets the contents of the cache for the resultset. Expects an arrayref
of objects of the same class as those produced by the resultset. Note that
-if the cache is set the resultset will return the cached objects rather
+if the cache is set, the resultset will return the cached objects rather
than re-querying the database even if the cache attr is not set.
The contents of the cache can also be populated by using the
=item Arguments: none
-=item Return Value: []
+=item Return Value: undef
=back
Clears the cache for the resultset.
-=cut
+=cut
+
+sub clear_cache {
+ shift->set_cache(undef);
+}
+
+=head2 is_paged
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: true, if the resultset has been paginated
+
+=back
+
+=cut
+
+sub is_paged {
+ my ($self) = @_;
+ return !!$self->{attrs}{page};
+}
+
+=head2 is_ordered
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: true, if the resultset has been ordered with C<order_by>.
+
+=back
+
+=cut
+
+sub is_ordered {
+ my ($self) = @_;
+ return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
+}
+
+=head2 related_resultset
+
+=over 4
+
+=item Arguments: $rel_name
+
+=item Return Value: L<$resultset|/search>
+
+=back
+
+Returns a related resultset for the supplied relationship name.
+
+ $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
+
+=cut
+
+sub related_resultset {
+ my ($self, $rel) = @_;
+
+ $self->{related_resultsets} ||= {};
+ return $self->{related_resultsets}{$rel} ||= do {
+ my $rsrc = $self->result_source;
+ my $rel_info = $rsrc->relationship_info($rel);
+
+ $self->throw_exception(
+ "search_related: result source '" . $rsrc->source_name .
+ "' has no such relationship $rel")
+ unless $rel_info;
+
+ my $attrs = $self->_chain_relationship($rel);
+
+ my $join_count = $attrs->{seen_join}{$rel};
+
+ my $alias = $self->result_source->storage
+ ->relname_to_table_alias($rel, $join_count);
+
+ # since this is search_related, and we already slid the select window inwards
+ # (the select/as attrs were deleted in the beginning), we need to flip all
+ # left joins to inner, so we get the expected results
+ # read the comment on top of the actual function to see what this does
+ $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
+
+
+ #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
+ delete @{$attrs}{qw(result_class alias)};
+
+ my $new_cache;
+
+ if (my $cache = $self->get_cache) {
+ if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
+ $new_cache = [ map { @{$_->related_resultset($rel)->get_cache||[]} }
+ @$cache ];
+ }
+ }
+
+ my $rel_source = $rsrc->related_source($rel);
+
+ my $new = do {
+
+ # The reason we do this now instead of passing the alias to the
+ # search_rs below is that if you wrap/overload resultset on the
+ # source you need to know what alias it's -going- to have for things
+ # to work sanely (e.g. RestrictWithObject wants to be able to add
+ # extra query restrictions, and these may need to be $alias.)
+
+ my $rel_attrs = $rel_source->resultset_attributes;
+ local $rel_attrs->{alias} = $alias;
+
+ $rel_source->resultset
+ ->search_rs(
+ undef, {
+ %$attrs,
+ where => $attrs->{where},
+ });
+ };
+ $new->set_cache($new_cache) if $new_cache;
+ $new;
+ };
+}
+
+=head2 current_source_alias
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: $source_alias
+
+=back
+
+Returns the current table alias for the result source this resultset is built
+on, that will be used in the SQL query. Usually it is C<me>.
+
+Currently the source alias that refers to the result set returned by a
+L</search>/L</find> family method depends on how you got to the resultset: it's
+C<me> by default, but eg. L</search_related> aliases it to the related result
+source name (and keeps C<me> referring to the original result set). The long
+term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
+(and make this method unnecessary).
+
+Thus it's currently necessary to use this method in predefined queries (see
+L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
+source alias of the current result set:
+
+ # in a result set class
+ sub modified_by {
+ my ($self, $user) = @_;
+
+ my $me = $self->current_source_alias;
+
+ return $self->search({
+ "$me.modified" => $user->id,
+ });
+ }
+
+=cut
+
+sub current_source_alias {
+ return (shift->{attrs} || {})->{alias} || 'me';
+}
+
+=head2 as_subselect_rs
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: L<$resultset|/search>
+
+=back
+
+Act as a barrier to SQL symbols. The resultset provided will be made into a
+"virtual view" by including it as a subquery within the from clause. From this
+point on, any joined tables are inaccessible to ->search on the resultset (as if
+it were simply where-filtered without joins). For example:
+
+ my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
+
+ # 'x' now pollutes the query namespace
+
+ # So the following works as expected
+ my $ok_rs = $rs->search({'x.other' => 1});
+
+ # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
+ # def) we look for one row with contradictory terms and join in another table
+ # (aliased 'x_2') which we never use
+ my $broken_rs = $rs->search({'x.name' => 'def'});
+
+ my $rs2 = $rs->as_subselect_rs;
+
+ # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
+ my $not_joined_rs = $rs2->search({'x.other' => 1});
+
+ # works as expected: finds a 'table' row related to two x rows (abc and def)
+ my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
+
+Another example of when one might use this would be to select a subset of
+columns in a group by clause:
+
+ my $rs = $schema->resultset('Bar')->search(undef, {
+ group_by => [qw{ id foo_id baz_id }],
+ })->as_subselect_rs->search(undef, {
+ columns => [qw{ id foo_id }]
+ });
+
+In the above example normally columns would have to be equal to the group by,
+but because we isolated the group by into a subselect the above works.
+
+=cut
+
+sub as_subselect_rs {
+ my $self = shift;
+
+ my $attrs = $self->_resolved_attrs;
+
+ my $fresh_rs = (ref $self)->new (
+ $self->result_source
+ );
+
+ # these pieces will be locked in the subquery
+ delete $fresh_rs->{cond};
+ delete @{$fresh_rs->{attrs}}{qw/where bind/};
+
+ return $fresh_rs->search( {}, {
+ from => [{
+ $attrs->{alias} => $self->as_query,
+ -alias => $attrs->{alias},
+ -rsrc => $self->result_source,
+ }],
+ alias => $attrs->{alias},
+ });
+}
+
+# This code is called by search_related, and makes sure there
+# is clear separation between the joins before, during, and
+# after the relationship. This information is needed later
+# in order to properly resolve prefetch aliases (any alias
+# with a relation_chain_depth less than the depth of the
+# current prefetch is not considered)
+#
+# The increments happen twice per join. An even number means a
+# relationship specified via a search_related, whereas an odd
+# number indicates a join/prefetch added via attributes
+#
+# Also this code will wrap the current resultset (the one we
+# chain to) in a subselect IFF it contains limiting attributes
+sub _chain_relationship {
+ my ($self, $rel) = @_;
+ my $source = $self->result_source;
+ my $attrs = { %{$self->{attrs}||{}} };
+
+ # we need to take the prefetch the attrs into account before we
+ # ->_resolve_join as otherwise they get lost - captainL
+ my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
+
+ delete @{$attrs}{qw/join prefetch collapse group_by distinct select as columns +select +as +columns/};
+
+ my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
+
+ my $from;
+ my @force_subq_attrs = qw/offset rows group_by having/;
+
+ if (
+ ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
+ ||
+ $self->_has_resolved_attr (@force_subq_attrs)
+ ) {
+ # Nuke the prefetch (if any) before the new $rs attrs
+ # are resolved (prefetch is useless - we are wrapping
+ # a subquery anyway).
+ my $rs_copy = $self->search;
+ $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
+ $rs_copy->{attrs}{join},
+ delete $rs_copy->{attrs}{prefetch},
+ );
+
+ $from = [{
+ -rsrc => $source,
+ -alias => $attrs->{alias},
+ $attrs->{alias} => $rs_copy->as_query,
+ }];
+ delete @{$attrs}{@force_subq_attrs, qw/where bind/};
+ $seen->{-relation_chain_depth} = 0;
+ }
+ elsif ($attrs->{from}) { #shallow copy suffices
+ $from = [ @{$attrs->{from}} ];
+ }
+ else {
+ $from = [{
+ -rsrc => $source,
+ -alias => $attrs->{alias},
+ $attrs->{alias} => $source->from,
+ }];
+ }
+
+ my $jpath = ($seen->{-relation_chain_depth})
+ ? $from->[-1][0]{-join_path}
+ : [];
+
+ my @requested_joins = $source->_resolve_join(
+ $join,
+ $attrs->{alias},
+ $seen,
+ $jpath,
+ );
+
+ push @$from, @requested_joins;
+
+ $seen->{-relation_chain_depth}++;
+
+ # if $self already had a join/prefetch specified on it, the requested
+ # $rel might very well be already included. What we do in this case
+ # is effectively a no-op (except that we bump up the chain_depth on
+ # the join in question so we could tell it *is* the search_related)
+ my $already_joined;
+
+ # we consider the last one thus reverse
+ for my $j (reverse @requested_joins) {
+ my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
+ if ($rel eq $last_j) {
+ $j->[0]{-relation_chain_depth}++;
+ $already_joined++;
+ last;
+ }
+ }
+
+ unless ($already_joined) {
+ push @$from, $source->_resolve_join(
+ $rel,
+ $attrs->{alias},
+ $seen,
+ $jpath,
+ );
+ }
+
+ $seen->{-relation_chain_depth}++;
-sub clear_cache {
- shift->set_cache(undef);
+ return {%$attrs, from => $from, seen_join => $seen};
}
-=head2 related_resultset
+sub _resolved_attrs {
+ my $self = shift;
+ return $self->{_attrs} if $self->{_attrs};
-=over 4
+ my $attrs = { %{ $self->{attrs} || {} } };
+ my $source = $self->result_source;
+ my $alias = $attrs->{alias};
-=item Arguments: $relationship_name
+ # default selection list
+ $attrs->{columns} = [ $source->columns ]
+ unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
-=item Return Value: $resultset
+ # merge selectors together
+ for (qw/columns select as/) {
+ $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
+ if $attrs->{$_} or $attrs->{"+$_"};
+ }
-=back
+ # disassemble columns
+ my (@sel, @as);
+ if (my $cols = delete $attrs->{columns}) {
+ for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
+ if (ref $c eq 'HASH') {
+ for my $as (sort keys %$c) {
+ push @sel, $c->{$as};
+ push @as, $as;
+ }
+ }
+ else {
+ push @sel, $c;
+ push @as, $c;
+ }
+ }
+ }
-Returns a related resultset for the supplied relationship name.
+ # when trying to weed off duplicates later do not go past this point -
+ # everything added from here on is unbalanced "anyone's guess" stuff
+ my $dedup_stop_idx = $#as;
+
+ push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
+ if $attrs->{as};
+ push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
+ if $attrs->{select};
+
+ # assume all unqualified selectors to apply to the current alias (legacy stuff)
+ $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
+
+ # disqualify all $alias.col as-bits (inflate-map mandated)
+ $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
+
+ # de-duplicate the result (remove *identical* select/as pairs)
+ # and also die on duplicate {as} pointing to different {select}s
+ # not using a c-style for as the condition is prone to shrinkage
+ my $seen;
+ my $i = 0;
+ while ($i <= $dedup_stop_idx) {
+ if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
+ splice @sel, $i, 1;
+ splice @as, $i, 1;
+ $dedup_stop_idx--;
+ }
+ elsif ($seen->{$as[$i]}++) {
+ $self->throw_exception(
+ "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
+ );
+ }
+ else {
+ $i++;
+ }
+ }
- $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
+ $attrs->{select} = \@sel;
+ $attrs->{as} = \@as;
-=cut
+ $attrs->{from} ||= [{
+ -rsrc => $source,
+ -alias => $self->{attrs}{alias},
+ $self->{attrs}{alias} => $source->from,
+ }];
-sub related_resultset {
- my ($self, $rel) = @_;
+ if ( $attrs->{join} || $attrs->{prefetch} ) {
- $self->{related_resultsets} ||= {};
- return $self->{related_resultsets}{$rel} ||= do {
- my $rel_obj = $self->result_source->relationship_info($rel);
+ $self->throw_exception ('join/prefetch can not be used with a custom {from}')
+ if ref $attrs->{from} ne 'ARRAY';
- $self->throw_exception(
- "search_related: result source '" . $self->result_source->source_name .
- "' has no such relationship $rel")
- unless $rel_obj;
-
- my ($from,$seen) = $self->_resolve_from($rel);
+ my $join = (delete $attrs->{join}) || {};
- my $join_count = $seen->{$rel};
- my $alias = ($join_count > 1 ? join('_', $rel, $join_count) : $rel);
+ if ( defined $attrs->{prefetch} ) {
+ $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
+ }
- #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
- my %attrs = %{$self->{attrs}||{}};
- delete @attrs{qw(result_class alias)};
+ $attrs->{from} = # have to copy here to avoid corrupting the original
+ [
+ @{ $attrs->{from} },
+ $source->_resolve_join(
+ $join,
+ $alias,
+ { %{ $attrs->{seen_join} || {} } },
+ ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
+ ? $attrs->{from}[-1][0]{-join_path}
+ : []
+ ,
+ )
+ ];
+ }
- my $new_cache;
+ if ( defined $attrs->{order_by} ) {
+ $attrs->{order_by} = (
+ ref( $attrs->{order_by} ) eq 'ARRAY'
+ ? [ @{ $attrs->{order_by} } ]
+ : [ $attrs->{order_by} || () ]
+ );
+ }
- if (my $cache = $self->get_cache) {
- if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
- $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
- @$cache ];
- }
+ if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
+ $attrs->{group_by} = [ $attrs->{group_by} ];
+ }
+
+ # generate the distinct induced group_by early, as prefetch will be carried via a
+ # subquery (since a group_by is present)
+ if (delete $attrs->{distinct}) {
+ if ($attrs->{group_by}) {
+ carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
+ }
+ else {
+ # distinct affects only the main selection part, not what prefetch may
+ # add below.
+ $attrs->{group_by} = $source->storage->_group_over_selection (
+ $attrs->{from},
+ $attrs->{select},
+ $attrs->{order_by},
+ );
}
+ }
- my $rel_source = $self->result_source->related_source($rel);
+ # generate selections based on the prefetch helper
+ my $prefetch;
+ $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
+ if defined $attrs->{prefetch};
- my $new = do {
+ if ($prefetch) {
- # The reason we do this now instead of passing the alias to the
- # search_rs below is that if you wrap/overload resultset on the
- # source you need to know what alias it's -going- to have for things
- # to work sanely (e.g. RestrictWithObject wants to be able to add
- # extra query restrictions, and these may need to be $alias.)
+ $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
+ if $attrs->{_dark_selector};
- my $attrs = $rel_source->resultset_attributes;
- local $attrs->{alias} = $alias;
+ $attrs->{collapse} = 1;
- $rel_source->resultset
- ->search_rs(
- undef, {
- %attrs,
- join => undef,
- prefetch => undef,
- select => undef,
- as => undef,
- where => $self->{cond},
- seen_join => $seen,
- from => $from,
- });
- };
- $new->set_cache($new_cache) if $new_cache;
- $new;
- };
-}
+ # this is a separate structure (we don't look in {from} directly)
+ # as the resolver needs to shift things off the lists to work
+ # properly (identical-prefetches on different branches)
+ my $join_map = {};
+ if (ref $attrs->{from} eq 'ARRAY') {
-sub _resolve_from {
- my ($self, $extra_join) = @_;
- my $source = $self->result_source;
- my $attrs = $self->{attrs};
-
- my $from = $attrs->{from}
- || [ { $attrs->{alias} => $source->from } ];
-
- my $seen = { %{$attrs->{seen_join}||{}} };
+ my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
- my $join = ($attrs->{join}
- ? [ $attrs->{join}, $extra_join ]
- : $extra_join);
+ for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
+ next unless $j->[0]{-alias};
+ next unless $j->[0]{-join_path};
+ next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
- # we need to take the prefetch the attrs into account before we
- # ->resolve_join as otherwise they get lost - captainL
- my $merged = $self->_merge_attr( $join, $attrs->{prefetch} );
+ my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
- $from = [
- @$from,
- ($join ? $source->resolve_join($merged, $attrs->{alias}, $seen) : ()),
- ];
+ my $p = $join_map;
+ $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
+ push @{$p->{-join_aliases} }, $j->[0]{-alias};
+ }
+ }
- return ($from,$seen);
-}
+ my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map );
-sub _resolved_attrs {
- my $self = shift;
- return $self->{_attrs} if $self->{_attrs};
+ # we need to somehow mark which columns came from prefetch
+ if (@prefetch) {
+ my $sel_end = $#{$attrs->{select}};
+ $attrs->{_prefetch_selector_range} = [ $sel_end + 1, $sel_end + @prefetch ];
+ }
- my $attrs = { %{$self->{attrs}||{}} };
- my $source = $self->result_source;
- my $alias = $attrs->{alias};
-
- $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
- if ($attrs->{columns}) {
- delete $attrs->{as};
- } elsif (!$attrs->{select}) {
- $attrs->{columns} = [ $source->columns ];
- }
-
- $attrs->{select} =
- ($attrs->{select}
- ? (ref $attrs->{select} eq 'ARRAY'
- ? [ @{$attrs->{select}} ]
- : [ $attrs->{select} ])
- : [ map { m/\./ ? $_ : "${alias}.$_" } @{delete $attrs->{columns}} ]
- );
- $attrs->{as} =
- ($attrs->{as}
- ? (ref $attrs->{as} eq 'ARRAY'
- ? [ @{$attrs->{as}} ]
- : [ $attrs->{as} ])
- : [ map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{$attrs->{select}} ]
- );
-
- my $adds;
- if ($adds = delete $attrs->{include_columns}) {
- $adds = [$adds] unless ref $adds eq 'ARRAY';
- push(@{$attrs->{select}}, @$adds);
- push(@{$attrs->{as}}, map { m/([^.]+)$/; $1 } @$adds);
- }
- if ($adds = delete $attrs->{'+select'}) {
- $adds = [$adds] unless ref $adds eq 'ARRAY';
- push(@{$attrs->{select}},
- map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds);
- }
- if (my $adds = delete $attrs->{'+as'}) {
- $adds = [$adds] unless ref $adds eq 'ARRAY';
- push(@{$attrs->{as}}, @$adds);
+ push @{ $attrs->{select} }, (map { $_->[0] } @prefetch);
+ push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
}
- $attrs->{from} ||= [ { 'me' => $source->from } ];
+ if ( ! List::Util::first { $_ =~ /\./ } @{$attrs->{as}} ) {
+ $attrs->{_single_object_inflation} = 1;
+ $attrs->{collapse} = 0;
+ }
- if (exists $attrs->{join} || exists $attrs->{prefetch}) {
- my $join = delete $attrs->{join} || {};
+ # run through the resulting joinstructure (starting from our current slot)
+ # and unset collapse if proven unnesessary
+ #
+ # also while we are at it find out if the current root source has
+ # been premultiplied by previous related_source chaining
+ #
+ # this allows to predict whether a root object with all other relation
+ # data set to NULL is in fact unique
+ if ($attrs->{collapse}) {
+
+ if (ref $attrs->{from} eq 'ARRAY') {
+
+ if (@{$attrs->{from}} <= 1) {
+ # no joins - no collapse
+ $attrs->{collapse} = 0;
+ }
+ else {
+ # find where our table-spec starts
+ my @fromlist = @{$attrs->{from}};
+ while (@fromlist) {
+ my $t = shift @fromlist;
+
+ my $is_multi;
+ # me vs join from-spec distinction - a ref means non-root
+ if (ref $t eq 'ARRAY') {
+ $t = $t->[0];
+ $is_multi ||= ! $t->{-is_single};
+ }
+ last if ($t->{-alias} && $t->{-alias} eq $alias);
+ $attrs->{_main_source_premultiplied} ||= $is_multi;
+ }
- if (defined $attrs->{prefetch}) {
- $join = $self->_merge_attr(
- $join, $attrs->{prefetch}
- );
-
+ # no non-singles remaining, nor any premultiplication - nothing to collapse
+ if (
+ ! $attrs->{_main_source_premultiplied}
+ and
+ ! List::Util::first { ! $_->[0]{-is_single} } @fromlist
+ ) {
+ $attrs->{collapse} = 0;
+ }
+ }
}
- $attrs->{from} = # have to copy here to avoid corrupting the original
- [
- @{$attrs->{from}},
- $source->resolve_join($join, $alias, { %{$attrs->{seen_join}||{}} })
- ];
-
+ else {
+ # if we can not analyze the from - err on the side of safety
+ $attrs->{_main_source_premultiplied} = 1;
+ }
}
- $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct};
- if ($attrs->{order_by}) {
- $attrs->{order_by} = (ref($attrs->{order_by}) eq 'ARRAY'
- ? [ @{$attrs->{order_by}} ]
- : [ $attrs->{order_by} ]);
- } else {
- $attrs->{order_by} = [];
- }
-
- my $collapse = $attrs->{collapse} || {};
- if (my $prefetch = delete $attrs->{prefetch}) {
- $prefetch = $self->_merge_attr({}, $prefetch);
- my @pre_order;
- my $seen = $attrs->{seen_join} || {};
- foreach my $p (ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch)) {
- # bring joins back to level of current class
- my @prefetch = $source->resolve_prefetch(
- $p, $alias, $seen, \@pre_order, $collapse
- );
- push(@{$attrs->{select}}, map { $_->[0] } @prefetch);
- push(@{$attrs->{as}}, map { $_->[1] } @prefetch);
- }
- push(@{$attrs->{order_by}}, @pre_order);
+ if (! $attrs->{order_by} and $attrs->{collapse}) {
+ # default order for collapsing unless the user asked for something
+ $attrs->{order_by} = [ map { "$alias.$_" } $source->primary_columns ];
+ $attrs->{_ordered_for_collapse} = 1;
+ $attrs->{_order_is_artificial} = 1;
}
- $attrs->{collapse} = $collapse;
- if ($attrs->{page}) {
- $attrs->{offset} ||= 0;
- $attrs->{offset} += ($attrs->{rows} * ($attrs->{page} - 1));
+ # if both page and offset are specified, produce a combined offset
+ # even though it doesn't make much sense, this is what pre 081xx has
+ # been doing
+ if (my $page = delete $attrs->{page}) {
+ $attrs->{offset} =
+ ($attrs->{rows} * ($page - 1))
+ +
+ ($attrs->{offset} || 0)
+ ;
}
return $self->{_attrs} = $attrs;
sub _rollout_attr {
my ($self, $attr) = @_;
-
+
if (ref $attr eq 'HASH') {
return $self->_rollout_hash($attr);
} elsif (ref $attr eq 'ARRAY') {
sub _calculate_score {
my ($self, $a, $b) = @_;
+ if (defined $a xor defined $b) {
+ return 0;
+ }
+ elsif (not defined $a) {
+ return 1;
+ }
+
if (ref $b eq 'HASH') {
my ($b_key) = keys %{$b};
if (ref $a eq 'HASH') {
}
} else {
return ($a eq $b_key) ? 1 : 0;
- }
+ }
} else {
if (ref $a eq 'HASH') {
my ($a_key) = keys %{$a};
}
}
-sub _merge_attr {
- my ($self, $a, $b) = @_;
+sub _merge_joinpref_attr {
+ my ($self, $orig, $import) = @_;
- return $b unless defined($a);
- return $a unless defined($b);
-
- $a = $self->_rollout_attr($a);
- $b = $self->_rollout_attr($b);
+ return $import unless defined($orig);
+ return $orig unless defined($import);
+
+ $orig = $self->_rollout_attr($orig);
+ $import = $self->_rollout_attr($import);
my $seen_keys;
- foreach my $b_element ( @{$b} ) {
- # find best candidate from $a to merge $b_element into
+ foreach my $import_element ( @{$import} ) {
+ # find best candidate from $orig to merge $b_element into
my $best_candidate = { position => undef, score => 0 }; my $position = 0;
- foreach my $a_element ( @{$a} ) {
- my $score = $self->_calculate_score( $a_element, $b_element );
+ foreach my $orig_element ( @{$orig} ) {
+ my $score = $self->_calculate_score( $orig_element, $import_element );
if ($score > $best_candidate->{score}) {
$best_candidate->{position} = $position;
$best_candidate->{score} = $score;
}
$position++;
}
- my ($b_key) = ( ref $b_element eq 'HASH' ) ? keys %{$b_element} : ($b_element);
+ my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
+ $import_key = '' if not defined $import_key;
- if ($best_candidate->{score} == 0 || exists $seen_keys->{$b_key}) {
- push( @{$a}, $b_element );
+ if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
+ push( @{$orig}, $import_element );
} else {
- my $a_best = $a->[$best_candidate->{position}];
- # merge a_best and b_element together and replace original with merged
- if (ref $a_best ne 'HASH') {
- $a->[$best_candidate->{position}] = $b_element;
- } elsif (ref $b_element eq 'HASH') {
- my ($key) = keys %{$a_best};
- $a->[$best_candidate->{position}] = { $key => $self->_merge_attr($a_best->{$key}, $b_element->{$key}) };
+ my $orig_best = $orig->[$best_candidate->{position}];
+ # merge orig_best and b_element together and replace original with merged
+ if (ref $orig_best ne 'HASH') {
+ $orig->[$best_candidate->{position}] = $import_element;
+ } elsif (ref $import_element eq 'HASH') {
+ my ($key) = keys %{$orig_best};
+ $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
}
}
- $seen_keys->{$b_key} = 1; # don't merge the same key twice
+ $seen_keys->{$import_key} = 1; # don't merge the same key twice
}
- return $a;
+ return @$orig ? $orig : ();
}
-sub result_source {
- my $self = shift;
+{
+ my $hm;
- if (@_) {
- $self->_source_handle($_[0]->handle);
- } else {
- $self->_source_handle->resolve;
- }
+ sub _merge_attr {
+ $hm ||= do {
+ require Hash::Merge;
+ my $hm = Hash::Merge->new;
+
+ $hm->specify_behavior({
+ SCALAR => {
+ SCALAR => sub {
+ my ($defl, $defr) = map { defined $_ } (@_[0,1]);
+
+ if ($defl xor $defr) {
+ return [ $defl ? $_[0] : $_[1] ];
+ }
+ elsif (! $defl) {
+ return [];
+ }
+ elsif (__HM_DEDUP and $_[0] eq $_[1]) {
+ return [ $_[0] ];
+ }
+ else {
+ return [$_[0], $_[1]];
+ }
+ },
+ ARRAY => sub {
+ return $_[1] if !defined $_[0];
+ return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
+ return [$_[0], @{$_[1]}]
+ },
+ HASH => sub {
+ return [] if !defined $_[0] and !keys %{$_[1]};
+ return [ $_[1] ] if !defined $_[0];
+ return [ $_[0] ] if !keys %{$_[1]};
+ return [$_[0], $_[1]]
+ },
+ },
+ ARRAY => {
+ SCALAR => sub {
+ return $_[0] if !defined $_[1];
+ return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
+ return [@{$_[0]}, $_[1]]
+ },
+ ARRAY => sub {
+ my @ret = @{$_[0]} or return $_[1];
+ return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
+ my %idx = map { $_ => 1 } @ret;
+ push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
+ \@ret;
+ },
+ HASH => sub {
+ return [ $_[1] ] if ! @{$_[0]};
+ return $_[0] if !keys %{$_[1]};
+ return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
+ return [ @{$_[0]}, $_[1] ];
+ },
+ },
+ HASH => {
+ SCALAR => sub {
+ return [] if !keys %{$_[0]} and !defined $_[1];
+ return [ $_[0] ] if !defined $_[1];
+ return [ $_[1] ] if !keys %{$_[0]};
+ return [$_[0], $_[1]]
+ },
+ ARRAY => sub {
+ return [] if !keys %{$_[0]} and !@{$_[1]};
+ return [ $_[0] ] if !@{$_[1]};
+ return $_[1] if !keys %{$_[0]};
+ return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
+ return [ $_[0], @{$_[1]} ];
+ },
+ HASH => sub {
+ return [] if !keys %{$_[0]} and !keys %{$_[1]};
+ return [ $_[0] ] if !keys %{$_[1]};
+ return [ $_[1] ] if !keys %{$_[0]};
+ return [ $_[0] ] if $_[0] eq $_[1];
+ return [ $_[0], $_[1] ];
+ },
+ }
+ } => 'DBIC_RS_ATTR_MERGER');
+ $hm;
+ };
+
+ return $hm->merge ($_[1], $_[2]);
+ }
+}
+
+sub STORABLE_freeze {
+ my ($self, $cloning) = @_;
+ my $to_serialize = { %$self };
+
+ # A cursor in progress can't be serialized (and would make little sense anyway)
+ # the parser can be regenerated (and can't be serialized)
+ delete @{$to_serialize}{qw/cursor _row_parser/};
+
+ # nor is it sensical to store a not-yet-fired-count pager
+ if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
+ delete $to_serialize->{pager};
+ }
+
+ Storable::nfreeze($to_serialize);
+}
+
+# need this hook for symmetry
+sub STORABLE_thaw {
+ my ($self, $cloning, $serialized) = @_;
+
+ %$self = %{ Storable::thaw($serialized) };
+
+ $self;
}
+
=head2 throw_exception
See L<DBIx::Class::Schema/throw_exception> for details.
sub throw_exception {
my $self=shift;
- if (ref $self && $self->_source_handle->schema) {
- $self->_source_handle->schema->throw_exception(@_)
- } else {
- croak(@_);
- }
+ if (ref $self and my $rsrc = $self->result_source) {
+ $rsrc->throw_exception(@_)
+ }
+ else {
+ DBIx::Class::Exception->throw(@_);
+ }
}
# XXX: FIXME: Attributes docs need clearing up
=head1 ATTRIBUTES
-The resultset takes various attributes that modify its behavior. Here's an
-overview of them:
+Attributes are used to refine a ResultSet in various ways when
+searching for data. They can be passed to any method which takes an
+C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
+L</count>.
+
+Default attributes can be set on the result class using
+L<DBIx::Class::ResultSource/resultset_attributes>. (Please read
+the CAVEATS on that feature before using it!)
+
+These are in no particular order:
=head2 order_by
=over 4
-=item Value: ($order_by | \@order_by)
+=item Value: ( $order_by | \@order_by | \%order_by )
=back
-Which column(s) to order the results by. This is currently passed
-through directly to SQL, so you can give e.g. C<year DESC> for a
-descending order on the column `year'.
+Which column(s) to order the results by.
-Please note that if you have C<quote_char> enabled (see
-L<DBIx::Class::Storage::DBI/connect_info>) you will need to do C<\'year DESC' > to
-specify an order. (The scalar ref causes it to be passed as raw sql to the DB,
-so you will need to manually quote things as appropriate.)
+[The full list of suitable values is documented in
+L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
+common options.]
+
+If a single column name, or an arrayref of names is supplied, the
+argument is passed through directly to SQL. The hashref syntax allows
+for connection-agnostic specification of ordering direction:
+
+ For descending order:
+
+ order_by => { -desc => [qw/col1 col2 col3/] }
+
+ For explicit ascending order:
+
+ order_by => { -asc => 'col' }
+
+The old scalarref syntax (i.e. order_by => \'year DESC') is still
+supported, although you are strongly encouraged to use the hashref
+syntax as outlined above.
=head2 columns
=back
-Shortcut to request a particular set of columns to be retrieved. Adds
-C<me.> onto the start of any column without a C<.> in it and sets C<select>
-from that, then auto-populates C<as> from C<select> as normal. (You may also
-use the C<cols> attribute, as in earlier versions of DBIC.)
+Shortcut to request a particular set of columns to be retrieved. Each
+column spec may be a string (a table column name), or a hash (in which
+case the key is the C<as> value, and the value is used as the C<select>
+expression). Adds C<me.> onto the start of any column without a C<.> in
+it and sets C<select> from that, then auto-populates C<as> from
+C<select> as normal. (You may also use the C<cols> attribute, as in
+earlier versions of DBIC.)
-=head2 include_columns
+Essentially C<columns> does the same as L</select> and L</as>.
+
+ columns => [ 'foo', { bar => 'baz' } ]
+
+is the same as
+
+ select => [qw/foo baz/],
+ as => [qw/foo bar/]
+
+=head2 +columns
=over 4
=back
-Shortcut to include additional columns in the returned results - for example
+Indicates additional columns to be selected from storage. Works the same
+as L</columns> but adds columns to the selection. (You may also use the
+C<include_columns> attribute, as in earlier versions of DBIC). For
+example:-
$schema->resultset('CD')->search(undef, {
- include_columns => ['artist.name'],
+ '+columns' => ['artist.name'],
join => ['artist']
});
column (or relationship) accessor, and 'name' is the name of the column
accessor in the related table.
+B<NOTE:> You need to explicitly quote '+columns' when defining the attribute.
+Not doing so causes Perl to incorrectly interpret +columns as a bareword with a
+unary plus operator before it.
+
+=head2 include_columns
+
+=over 4
+
+=item Value: \@columns
+
+=back
+
+Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
+
=head2 select
=over 4
select => [
'name',
{ count => 'employeeid' },
- { sum => 'salary' }
+ { max => { length => 'name' }, -as => 'longest_name' }
]
});
-When you use function/stored procedure names and do not supply an C<as>
-attribute, the column names returned are storage-dependent. E.g. MySQL would
-return a column named C<count(employeeid)> in the above example.
+ # Equivalent SQL
+ SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
+
+B<NOTE:> You will almost always need a corresponding L</as> attribute when you
+use L</select>, to instruct DBIx::Class how to store the result of the column.
+Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
+identifier aliasing. You can however alias a function, so you can use it in
+e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
+attribute> supplied as shown in the example above.
+
+B<NOTE:> You need to explicitly quote '+select'/'+as' when defining the attributes.
+Not doing so causes Perl to incorrectly interpret them as a bareword with a
+unary plus operator before it.
=head2 +select
=over 4
Indicates additional columns to be selected from storage. Works the same as
-L</select> but adds columns to the selection.
+L</select> but adds columns to the default selection, instead of specifying
+an explicit list.
=back
=over 4
-Indicates additional column names for those added via L</+select>.
+Indicates additional column names for those added via L</+select>. See L</as>.
=back
=back
-Indicates column names for object inflation. That is, C<as>
-indicates the name that the column can be accessed as via the
-C<get_column> method (or via the object accessor, B<if one already
-exists>). It has nothing to do with the SQL code C<SELECT foo AS bar>.
-
-The C<as> attribute is used in conjunction with C<select>,
-usually when C<select> contains one or more function or stored
-procedure names:
+Indicates column names for object inflation. That is L</as> indicates the
+slot name in which the column value will be stored within the
+L<Row|DBIx::Class::Row> object. The value will then be accessible via this
+identifier by the C<get_column> method (or via the object accessor B<if one
+with the same name already exists>) as shown below. The L</as> attribute has
+B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
$rs = $schema->resultset('Employee')->search(undef, {
select => [
'name',
- { count => 'employeeid' }
+ { count => 'employeeid' },
+ { max => { length => 'name' }, -as => 'longest_name' }
],
- as => ['name', 'employee_count'],
+ as => [qw/
+ name
+ employee_count
+ max_name_length
+ /],
});
- my $employee = $rs->first(); # get the first Employee
-
If the object against which the search is performed already has an accessor
matching a column name specified in C<as>, the value can be retrieved using
the accessor as normal:
You can create your own accessors if required - see
L<DBIx::Class::Manual::Cookbook> for details.
-Please note: This will NOT insert an C<AS employee_count> into the SQL
-statement produced, it is used for internal access only. Thus
-attempting to use the accessor in an C<order_by> clause or similar
-will fail miserably.
-
-To get around this limitation, you can supply literal SQL to your
-C<select> attibute that contains the C<AS alias> text, eg:
-
- select => [\'myfield AS alias']
-
=head2 join
=over 4
}
);
-You need to use the relationship (not the table) name in conditions,
-because they are aliased as such. The current table is aliased as "me", so
+You need to use the relationship (not the table) name in conditions,
+because they are aliased as such. The current table is aliased as "me", so
you need to use me.column_name in order to avoid ambiguity. For example:
- # Get CDs from 1984 with a 'Foo' track
+ # Get CDs from 1984 with a 'Foo' track
my $rs = $schema->resultset('CD')->search(
- {
+ {
'me.year' => 1984,
'tracks.name' => 'Foo'
},
{ join => 'tracks' }
);
-
+
If the same join is supplied twice, it will be aliased to <rel>_2 (and
similarly for a third time). For e.g.
If you want to fetch related objects from other tables as well, see C<prefetch>
below.
+ NOTE: An internal join-chain pruner will discard certain joins while
+ constructing the actual SQL query, as long as the joins in question do not
+ affect the retrieved result. This for example includes 1:1 left joins
+ that are not part of the restriction specification (WHERE/HAVING) nor are
+ a part of the query selection.
+
For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
=head2 prefetch
case.
Simple prefetches will be joined automatically, so there is no need
-for a C<join> attribute in the above search.
+for a C<join> attribute in the above search.
-C<prefetch> can be used with the following relationship types: C<belongs_to>,
-C<has_one> (or if you're using C<add_relationship>, any relationship declared
-with an accessor type of 'single' or 'filter'). A more complex example that
-prefetches an artists cds, the tracks on those cds, and the tags associted
-with that artist is given below (assuming many-to-many from artists to tags):
+L</prefetch> can be used with the any of the relationship types and
+multiple prefetches can be specified together. Below is a more complex
+example that prefetches a CD's artist, its liner notes (if present),
+the cover image, the tracks on that cd, and the guests on those
+tracks.
+
+ # Assuming:
+ My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
+ My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
+ My::Schema::CD->has_one( cover_image => 'My::Schema::Artwork' );
+ My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
+
+ My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
+
+ My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
+
+
+ my $rs = $schema->resultset('CD')->search(
+ undef,
+ {
+ prefetch => [
+ { artist => 'record_label'}, # belongs_to => belongs_to
+ 'liner_note', # might_have
+ 'cover_image', # has_one
+ { tracks => 'guests' }, # has_many => has_many
+ ]
+ }
+ );
- my $rs = $schema->resultset('Artist')->search(
+This will produce SQL like the following:
+
+ SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
+ tracks.*, guests.*
+ FROM cd me
+ JOIN artist artist
+ ON artist.artistid = me.artistid
+ JOIN record_label record_label
+ ON record_label.labelid = artist.labelid
+ LEFT JOIN track tracks
+ ON tracks.cdid = me.cdid
+ LEFT JOIN guest guests
+ ON guests.trackid = track.trackid
+ LEFT JOIN liner_notes liner_note
+ ON liner_note.cdid = me.cdid
+ JOIN cd_artwork cover_image
+ ON cover_image.cdid = me.cdid
+ ORDER BY tracks.cd
+
+Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
+C<tracks>, and C<guests> of the CD will all be available through the
+relationship accessors without the need for additional queries to the
+database.
+
+However, there is one caveat to be observed: it can be dangerous to
+prefetch more than one L<has_many|DBIx::Class::Relationship/has_many>
+relationship on a given level. e.g.:
+
+ my $rs = $schema->resultset('CD')->search(
undef,
{
prefetch => [
- { cds => 'tracks' },
- { artist_tags => 'tags' }
+ 'tracks', # has_many
+ { cd_to_producer => 'producer' }, # has_many => belongs_to (i.e. m2m)
]
}
);
-
-B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
-attributes will be ignored.
+The collapser currently can't identify duplicate tuples for multiple
+L<has_many|DBIx::Class::Relationship/has_many> relationships and as a
+result the second L<has_many|DBIx::Class::Relationship/has_many>
+relation could contain redundant objects.
+
+=head3 Using L</prefetch> with L</join>
+
+L</prefetch> implies a L</join> with the equivalent argument, and is
+properly merged with any existing L</join> specification. So the
+following:
+
+ my $rs = $schema->resultset('CD')->search(
+ {'record_label.name' => 'Music Product Ltd.'},
+ {
+ join => {artist => 'record_label'},
+ prefetch => 'artist',
+ }
+ );
+
+... will work, searching on the record label's name, but only
+prefetching the C<artist>.
+
+=head3 Using L</prefetch> with L</select> / L</+select> / L</as> / L</+as>
+
+L</prefetch> implies a L</+select>/L</+as> with the fields of the
+prefetched relations. So given:
+
+ my $rs = $schema->resultset('CD')->search(
+ undef,
+ {
+ select => ['cd.title'],
+ as => ['cd_title'],
+ prefetch => 'artist',
+ }
+ );
+
+The L</select> becomes: C<'cd.title', 'artist.*'> and the L</as>
+becomes: C<'cd_title', 'artist.*'>.
+
+=head3 CAVEATS
+
+Prefetch does a lot of deep magic. As such, it may not behave exactly
+as you might expect.
+
+=over 4
+
+=item *
+
+Prefetch uses the L</cache> to populate the prefetched relationships. This
+may or may not be what you want.
+
+=item *
+
+If you specify a condition on a prefetched relationship, ONLY those
+rows that match the prefetched condition will be fetched into that relationship.
+This means that adding prefetch to a search() B<may alter> what is returned by
+traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
+
+ my $artist_rs = $schema->resultset('Artist')->search({
+ 'cds.year' => 2008,
+ }, {
+ join => 'cds',
+ });
+
+ my $count = $artist_rs->first->cds->count;
+
+ my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
+
+ my $prefetch_count = $artist_rs_prefetch->first->cds->count;
+
+ cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
+
+that cmp_ok() may or may not pass depending on the datasets involved. This
+behavior may or may not survive the 0.09 transition.
+
+=back
+
+=head2 alias
+
+=over 4
+
+=item Value: $source_alias
+
+=back
+
+Sets the source alias for the query. Normally, this defaults to C<me>, but
+nested search queries (sub-SELECTs) might need specific aliases set to
+reference inner queries. For example:
+
+ my $q = $rs
+ ->related_resultset('CDs')
+ ->related_resultset('Tracks')
+ ->search({
+ 'track.id' => { -ident => 'none_search.id' },
+ })
+ ->as_query;
+
+ my $ids = $self->search({
+ -not_exists => $q,
+ }, {
+ alias => 'none_search',
+ group_by => 'none_search.id',
+ })->get_column('id')->as_query;
+
+ $self->search({ id => { -in => $ids } })
+
+This attribute is directly tied to L</current_source_alias>.
=head2 page
identical to creating a non-pages resultset and then calling ->page($page)
on it.
-If L<rows> attribute is not specified it defualts to 10 rows per page.
+If L</rows> attribute is not specified it defaults to 10 rows per page.
+
+When you have a paged resultset, L</count> will only return the number
+of rows in the page. To get the total, use the L</pager> and call
+C<total_entries> on it.
=head2 rows
=back
-Specifes the maximum number of rows for direct retrieval or the number of
+Specifies the maximum number of rows for direct retrieval or the number of
rows per page if the page attribute or method is used.
=head2 offset
Specifies the (zero-based) row number for the first row to be returned, or the
of the first row of the first page if paging is used.
+=head2 software_limit
+
+=over 4
+
+=item Value: (0 | 1)
+
+=back
+
+When combined with L</rows> and/or L</offset> the generated SQL will not
+include any limit dialect stanzas. Instead the entire result will be selected
+as if no limits were specified, and DBIC will perform the limit locally, by
+artificially advancing and finishing the resulting L</cursor>.
+
+This is the recommended way of performing resultset limiting when no sane RDBMS
+implementation is available (e.g.
+L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
+L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
+
=head2 group_by
=over 4
ORDER BY. It is applied to the after the grouping calculations have been
done.
- having => { 'count(employee)' => { '>=', 100 } }
+ having => { 'count_employee' => { '>=', 100 } }
+
+or with an in-place function in which case literal SQL is required:
+
+ having => \[ 'count(employee) >= ?', [ count => 100 ] ]
=head2 distinct
=back
-Set to 1 to group by all columns.
+Set to 1 to group by all columns. If the resultset already has a group_by
+attribute, this setting is ignored and an appropriate warning is issued.
=head2 where
Adds to the WHERE clause.
# only return rows WHERE deleted IS NULL for all searches
- __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
+ __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
+
+Can be overridden by passing C<< { where => undef } >> as an attribute
+to a resultset.
-Can be overridden by passing C<{ where => undef }> as an attribute
-to a resulset.
+For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
=back
For more examples of using these attributes, see
L<DBIx::Class::Manual::Cookbook>.
-=head2 from
+=head2 for
=over 4
-=item Value: \@from_clause
+=item Value: ( 'update' | 'shared' | \$scalar )
=back
-The C<from> attribute gives you manual control over the C<FROM> clause of SQL
-statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
-clauses.
+Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
+... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
+query.
+
+=head1 DBIC BIND VALUES
-NOTE: Use this on your own risk. This allows you to shoot off your foot!
+Because DBIC may need more information to bind values than just the column name
+and value itself, it uses a special format for both passing and receiving bind
+values. Each bind value should be composed of an arrayref of
+C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
-C<join> will usually do what you need and it is strongly recommended that you
-avoid using C<from> unless you cannot achieve the desired result using C<join>.
-And we really do mean "cannot", not just tried and failed. Attempting to use
-this because you're having problems with C<join> is like trying to use x86
-ASM because you've got a syntax error in your C. Trust us on this.
+=over 4
-Now, if you're still really, really sure you need to use this (and if you're
-not 100% sure, ask the mailing list first), here's an explanation of how this
-works.
+=item dbd_attrs
-The syntax is as follows -
+If present (in any form), this is what is being passed directly to bind_param.
+Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
+a single numerical type, while DBD::Pg takes a hashref if bind options.)
- [
- { <alias1> => <table1> },
- [
- { <alias2> => <table2>, -join_type => 'inner|left|right' },
- [], # nested JOIN (optional)
- { <table1.column1> => <table2.column2>, ... (more conditions) },
- ],
- # More of the above [ ] may follow for additional joins
- ]
-
- <table1> <alias1>
- JOIN
- <table2> <alias2>
- [JOIN ...]
- ON <table1.column1> = <table2.column2>
- <more joins may follow>
-
-An easy way to follow the examples below is to remember the following:
-
- Anything inside "[]" is a JOIN
- Anything inside "{}" is a condition for the enclosing JOIN
-
-The following examples utilize a "person" table in a family tree application.
-In order to express parent->child relationships, this table is self-joined:
-
- # Person->belongs_to('father' => 'Person');
- # Person->belongs_to('mother' => 'Person');
-
-C<from> can be used to nest joins. Here we return all children with a father,
-then search against all mothers of those children:
-
- $rs = $schema->resultset('Person')->search(
- undef,
- {
- alias => 'mother', # alias columns in accordance with "from"
- from => [
- { mother => 'person' },
- [
- [
- { child => 'person' },
- [
- { father => 'person' },
- { 'father.person_id' => 'child.father_id' }
- ]
- ],
- { 'mother.person_id' => 'child.mother_id' }
- ],
- ]
- },
- );
+If this is specified, all other bind options described below are ignored.
- # Equivalent SQL:
- # SELECT mother.* FROM person mother
- # JOIN (
- # person child
- # JOIN person father
- # ON ( father.person_id = child.father_id )
- # )
- # ON ( mother.person_id = child.mother_id )
-
-The type of any join can be controlled manually. To search against only people
-with a father in the person table, we could explicitly use C<INNER JOIN>:
-
- $rs = $schema->resultset('Person')->search(
- undef,
- {
- alias => 'child', # alias columns in accordance with "from"
- from => [
- { child => 'person' },
- [
- { father => 'person', -join_type => 'inner' },
- { 'father.id' => 'child.father_id' }
- ],
- ]
- },
- );
+=item sqlt_datatype
- # Equivalent SQL:
- # SELECT child.* FROM person child
- # INNER JOIN person father ON child.father_id = father.id
+If present, this is used to infer the actual bind attribute by passing to
+C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
+"data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
-=head2 for
+Note that the data type is somewhat freeform (hence the sqlt_ prefix);
+currently drivers are expected to "Do the Right Thing" when given a common
+datatype name. (Not ideal, but that's what we got at this point.)
-=over 4
+=item sqlt_size
-=item Value: ( 'update' | 'shared' )
+Currently used to correctly allocate buffers for bind_param_inout().
+Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
+or to a sensible value based on the "data_type".
+
+=item dbic_colname
+
+Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
+explicitly specified they are never overriden). Also used by some weird DBDs,
+where the column name should be available at bind_param time (e.g. Oracle).
=back
-Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
-... FOR SHARED.
+For backwards compatibility and convenience, the following shortcuts are
+supported:
+
+ [ $name => $val ] === [ { dbic_colname => $name }, $val ]
+ [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
+ [ undef, $val ] === [ {}, $val ]
+
+=head1 AUTHOR AND CONTRIBUTORS
+
+See L<AUTHOR|DBIx::Class/AUTHOR> and L<CONTRIBUTORS|DBIx::Class/CONTRIBUTORS> in DBIx::Class
+
+=head1 LICENSE
+
+You may distribute this code under the same terms as Perl itself.
=cut
projects / dbsrgits/DBIx-Class.git / blobdiff