use warnings;
use base qw/DBIx::Class/;
use DBIx::Class::Carp;
-use DBIx::Class::Exception;
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 ();
=head1 SYNOPSIS
- my $users_rs = $schema->resultset('User');
+ 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 $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
=head1 DESCRIPTION
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
sub get_data {
my $self = shift;
my $request = $self->get_request; # Get a request object somehow.
- my $schema = $self->get_schema; # Get the DBIC schema object somehow.
+ my $schema = $self->result_source->schema;
my $cd_rs = $schema->resultset('CD')->search({
title => $request->param('title'),
=head3 Resolving conditions and attributes
-When a resultset is chained from another resultset, conditions and
-attributes with the same keys need resolving.
+When a resultset is chained from another resultset (ie:
+C<my $new_rs = $old_rs->search(\%extra_cond, \%attrs)>), conditions
+and attributes with the same keys need resolving.
+
+If any of L</columns>, L</select>, L</as> are present, they reset the
+original selection, and start the selection "clean".
-L</join>, L</prefetch>, L</+select>, L</+as> attributes are merged
-into the existing ones from the original resultset.
+The L</join>, L</prefetch>, L</+columns>, 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
=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
attrs => $attrs,
}, $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};
+
$self->result_class(
$attrs->{result_class} || $source->result_class
);
=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>.
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>, L</create> and L</find>. The user must ensure
+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>.
+L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
=cut
=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;
- # Special-case handling for (undef, undef).
- if ( @_ == 2 && !defined $_[1] && !defined $_[0] ) {
- @_ = ();
- }
+ my $rsrc = $self->result_source;
+ my ($call_cond, $call_attrs);
- my $call_attrs = {};
- if (@_ > 1) {
- if (ref $_[-1] eq 'HASH') {
- # copy for _normalize_selection
- $call_attrs = { %{ pop @_ } };
- }
- elsif (! defined $_[-1] ) {
- pop @_; # search({}, undef)
+ # Special-case handling for (undef, undef) or (undef)
+ # Note that (foo => undef) is valid deprecated syntax
+ @_ = () if not scalar grep { defined $_ } @_;
+
+ # 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)
$cache = $self->get_cache;
}
- my $rsrc = $self->result_source;
-
my $old_attrs = { %{$self->{attrs}} };
my $old_having = delete $old_attrs->{having};
my $old_where = delete $old_attrs->{where};
my $new_attrs = { %$old_attrs };
# take care of call attrs (only if anything is changing)
- if (keys %$call_attrs) {
+ if ($call_attrs and keys %$call_attrs) {
- $self->throw_exception ('_trailing_select is not a public attribute - do not use it in search()')
- if ( exists $call_attrs->{_trailing_select} or exists $call_attrs->{'+_trailing_select'} );
+ # copy for _normalize_selection
+ $call_attrs = { %$call_attrs };
- my @selector_attrs = qw/select as columns cols +select +as +columns include_columns _trailing_select +_trailing_select/;
+ my @selector_attrs = qw/select as columns cols +select +as +columns include_columns/;
- # Normalize the selector list (operates on the passed-in attr structure)
+ # 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 separate 'as'-ed from blind 'select's
+ # 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};
- # 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};
- }
-
for (@selector_attrs) {
$new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
}
- # rip apart the rest of @_, parse a condition
- my $call_cond = do {
-
- if (ref $_[0] eq 'HASH') {
- (keys %{$_[0]}) ? $_[0] : undef
- }
- elsif (@_ == 1) {
- $_[0]
- }
- elsif (@_ % 2) {
- $self->throw_exception('Odd number of arguments to search')
- }
- else {
- +{ @_ }
- }
-
- } if @_;
-
- if( @_ > 1 and ! $rsrc->result_class->isa('DBIx::Class::CDBICompat') ) {
- carp_unique 'search( %condition ) is deprecated, use search( \%condition ) instead';
- }
-
for ($old_where, $call_cond) {
if (defined $_) {
$new_attrs->{where} = $self->_stack_cond (
return $rs;
}
+my $dark_sel_dumper;
sub _normalize_selection {
my ($self, $attrs) = @_;
$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
# 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 transport it over a separate attribute to make sure it is
- # the last thing in the select list, thus unable to throw off the corresponding
- # 'as' chain
+ # is ok as well), but make sure no more additions to the 'as' chain take place
for my $pref ('', '+') {
my ($sel, $as) = map {
);
}
elsif( ! @$as ) {
- # no as part supplied at all - try to deduce
+ # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
# if any @$as has been supplied we assume the user knows what (s)he is doing
# and blindly keep stacking up pieces
- my (@new_sel, @new_trailing);
- for (@$sel) {
- if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
- push @$as, $_->{-as};
- push @new_sel, $_;
- }
- # 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, $_;
- push @new_sel, $_;
- }
- # if all else fails - shove the selection to the trailing stack and move on
- else {
- push @new_trailing, $_;
+ unless ($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, $_;
+ }
+ # 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([$_])->Dump
+ ,
+ };
+ last SELECTOR;
+ }
}
}
-
- @$sel = @new_sel;
- $attrs->{"${pref}_trailing_select"} = $self->_merge_attr($attrs->{"${pref}_trailing_select"}, \@new_trailing)
- if @new_trailing;
}
elsif (@$as < @$sel) {
$self->throw_exception(
"Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
);
}
-
- # now see what the result for this pair looks like:
- if (@$as == @$sel) {
-
- # if balanced - treat as a columns entry
- $attrs->{"${pref}columns"} = $self->_merge_attr(
- $attrs->{"${pref}columns"},
- [ map { +{ $as->[$_] => $sel->[$_] } } ( 0 .. $#$as ) ]
+ elsif ($pref and $attrs->{_dark_selector}) {
+ $self->throw_exception(
+ "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
);
}
- else {
- # unbalanced - shove in select/as, not subject to deduplication in _resolved_attrs
- $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
- $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
- }
- }
+
+ # 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;
+ }
+
+
if (defined $left xor defined $right) {
return defined $left ? $left : $right;
}
- elsif (defined $left) {
- return { -and => [ map
- { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
- ($left, $right)
- ]};
+ elsif (! defined $left) {
+ return undef;
+ }
+ else {
+ return { -and => [ $left, $right ] };
}
-
- return undef;
}
=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. C<search_literal> is a convenience method.
-It is equivalent to calling $schema->search(\[]), but if you want to ensure
-columns are bound correctly, use C<search>.
-
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 ] ]);
-
-See L<DBIx::Class::Manual::Cookbook/Searching> and
-L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
-require C<search_literal>.
-
=cut
sub search_literal {
if ( @bind && ref($bind[-1]) eq 'HASH' ) {
$attr = pop @bind;
}
- return $self->search(\[ $sql, map [ __DUMMY__ => $_ ], @bind ], ($attr || () ));
+ return $self->search(\[ $sql, map [ {} => $_ ], @bind ], ($attr || () ));
}
=head2 find
=over 4
-=item Arguments: \%columns_values | @pk_values, \%attrs?
+=item Arguments: \%columns_values | @pk_values, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
-=item Return Value: $row_object | undef
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
=back
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<$row_object>.
+C<$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.
my $rsrc = $self->result_source;
+ 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")
+ ;
+ }
+
# Parse out the condition from input
my $call_cond;
+
if (ref $_[0] eq 'HASH') {
$call_cond = { %{$_[0]} };
}
else {
- my $constraint = exists $attrs->{key} ? $attrs->{key} : 'primary';
- my @c_cols = $rsrc->unique_constraint_columns($constraint);
+ # 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' constraint?"
+ "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'"
+ . "corresponding to the columns of the specified unique constraint '$constraint_name'"
) unless @c_cols == @_;
$call_cond = {};
my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
my $final_cond;
- if (exists $attrs->{key}) {
+ if (defined $constraint_name) {
$final_cond = $self->_qualify_cond_columns (
$self->_build_unique_cond (
- $attrs->{key},
+ $constraint_name,
$call_cond,
),
# 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 (keys %{$rs->_resolved_attrs->{collapse}}) {
+ if ($rs->_resolved_attrs->{collapse}) {
my $row = $rs->next;
carp "Query returned more than one row" if $rs->next;
return $row;
and
!$ENV{DBIC_NULLABLE_KEY_NOWARN}
and
- my @undefs = grep { ! defined $final_cond->{$_} } (keys %$final_cond)
+ my @undefs = sort grep { ! defined $final_cond->{$_} } (keys %$final_cond)
) {
carp_unique ( sprintf (
"NULL/undef values supplied for requested unique constraint '%s' (NULL "
=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 {
=item Arguments: none
-=item Return Value: $cursor
+=item Return Value: L<$cursor|DBIx::Class::Cursor>
=back
=cut
sub cursor {
- my ($self) = @_;
-
- my $attrs = $self->_resolved_attrs_copy;
+ my $self = shift;
- 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: $row_object | undef
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
=back
$self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
}
- my $attrs = $self->_resolved_attrs_copy;
+ my $attrs = { %{$self->_resolved_attrs} };
- if (keys %{$attrs->{collapse}}) {
- $self->throw_exception(
- 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
- );
- }
+ $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}) {
}
}
- 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];
}
=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
=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
=item Arguments: none
-=item Return Value: $result | undef
+=item Return Value: L<$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) = @_;
+ return shift(@{$self->{stashed_objects}}) if @{ $self->{stashed_objects}||[] };
+
+ $self->{stashed_objects} = $self->_construct_objects
+ or return undef;
- my $info = $self->_collapse_result($self->{_attrs}{as}, \@row)
- or return ();
- my @new = $self->result_class->inflate_result($self->result_source, @$info);
- @new = $self->{_attrs}{record_filter}->(@new)
- if exists $self->{_attrs}{record_filter};
- return @new;
+ return shift @{$self->{stashed_objects}};
}
-sub _collapse_result {
- my ($self, $as_proto, $row) = @_;
+# Constructs as many objects as it can in one pass while respecting
+# cursor laziness. Several modes of operation:
+#
+# * Always builds everything present in @{$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, $fetch_all) = @_;
- my @copy = @$row;
+ my $rsrc = $self->result_source;
+ my $attrs = $self->_resolved_attrs;
- # 'foo' => [ undef, 'foo' ]
- # 'foo.bar' => [ 'foo', 'bar' ]
- # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
+ if (!$fetch_all and ! $attrs->{order_by} and $attrs->{collapse}) {
+ # default order for collapsing unless the user asked for something
+ $attrs->{order_by} = [ map { join '.', $attrs->{alias}, $_} $rsrc->primary_columns ];
+ $attrs->{_ordered_for_collapse} = 1;
+ $attrs->{_order_is_artificial} = 1;
+ }
- my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
+ my $cursor = $self->cursor;
- my %collapse = %{$self->{_attrs}{collapse}||{}};
+ # 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 $self->{stashed_rows};
- my @pri_index;
+ if ($fetch_all) {
+ # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
+ $rows = [ ($rows ? @$rows : ()), $cursor->all ];
+ }
+ elsif( $attrs->{collapse} ) {
- # 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.
+ $attrs->{_ordered_for_collapse} = (!$attrs->{order_by}) ? 0 : do {
+ my $st = $rsrc->schema->storage;
+ my @ord_cols = map
+ { $_->[0] }
+ ( $st->_extract_order_criteria($attrs->{order_by}) )
+ ;
- # 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
+ my $colinfos = $st->_resolve_column_info($attrs->{from}, \@ord_cols);
- # store just the index so we can check the array positions from the row
- # without having to contruct the full hash
+ for (0 .. $#ord_cols) {
+ if (
+ ! $colinfos->{$ord_cols[$_]}
+ or
+ $colinfos->{$ord_cols[$_]}{-result_source} != $rsrc
+ ) {
+ splice @ord_cols, $_;
+ last;
+ }
+ }
- if (keys %collapse) {
- my %pri = map { ($_ => 1) } $self->result_source->_pri_cols;
- 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);
+ # 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;
+ } unless defined $attrs->{_ordered_for_collapse};
+
+ if (! $attrs->{_ordered_for_collapse}) {
+ $fetch_all = 1;
+
+ # instead of looping over ->next, use ->all in stealth mode
+ # *without* calling a ->reset afterwards
+ # FIXME - encapsulation breach, got to be a better way
+ if (! $cursor->{_done}) {
+ $rows = [ ($rows ? @$rows : ()), $cursor->all ];
+ $cursor->{_done} = 1;
}
- last unless keys %pri; # short circuit (Johnny Five Is Alive!)
}
}
- # no need to do an if, it'll be empty if @pri_index is empty anyway
-
- my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
-
- my @const_rows;
-
- do { # no need to check anything at the front, we always want the first row
+ if (! $fetch_all and ! @{$rows||[]} ) {
+ # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
+ if (scalar (my @r = $cursor->next) ) {
+ $rows = [ \@r ];
+ }
+ }
- my %const;
+ return undef unless @{$rows||[]};
- foreach my $this_as (@construct_as) {
- $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
- }
+ my @extra_collapser_args;
+ if ($attrs->{collapse} and ! $fetch_all ) {
- push(@const_rows, \%const);
+ @extra_collapser_args = (
+ # 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
+ );
+ }
- } until ( # no pri_index => no collapse => drop straight out
- !@pri_index
- or
- do { # get another row, stash it, drop out if different PK
+ # hotspot - skip the setter
+ my $res_class = $self->_result_class;
- @copy = $self->cursor->next;
- $self->{stashed_row} = \@copy;
+ my $inflator_cref = $self->{_result_inflator}{cref} ||= do {
+ $res_class->can ('inflate_result')
+ or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
+ };
- # last thing in do block, counts as true if anything doesn't match
+ my $infmap = $attrs->{as};
- # check xor defined first for NULL vs. NOT NULL then if one is
- # defined the other must be so check string equality
+ $self->{_result_inflator}{is_hri} = do { ( $inflator_cref == (
+ require DBIx::Class::ResultClass::HashRefInflator
+ &&
+ DBIx::Class::ResultClass::HashRefInflator->can('inflate_result')
+ ) ) ? 1 : 0
+ } unless defined $self->{_result_inflator}{is_hri};
- grep {
- (defined $pri_vals{$_} ^ defined $copy[$_])
- || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
- } @pri_index;
+ if ($attrs->{_single_resultclass_inflation}) {
+ # construct a much simpler array->hash folder for the one-table cases right here
+ if ($self->{_result_inflator}{is_hri}) {
+ for my $r (@$rows) {
+ $r = { map { $infmap->[$_] => $r->[$_] } 0..$#$infmap };
}
- );
+ }
+ # FIXME SUBOPTIMAL this is a very very very hot spot
+ # while rather optimal we can *still* do much better, by
+ # building a smarter Row::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
+ elsif (@$rows < 60) {
+ for my $r (@$rows) {
+ $r = $inflator_cref->($res_class, $rsrc, { map { $infmap->[$_] => $r->[$_] } (0..$#$infmap) } );
+ }
+ }
+ else {
+ eval sprintf (
+ '$_ = $inflator_cref->($res_class, $rsrc, { %s }) for @$rows',
+ join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap )
+ );
+ }
+ }
+ # Special-case multi-object HRI (we always prune)
+ elsif ($self->{_result_inflator}{is_hri}) {
+ ( $self->{_row_parser}{hri} ||= $rsrc->_mk_row_parser({
+ eval => 1,
+ inflate_map => $infmap,
+ selection => $attrs->{select},
+ collapse => $attrs->{collapse},
+ premultiplied => $attrs->{_main_source_premultiplied},
+ hri_style => 1,
+ prune_null_branches => 1,
+ }) )->($rows, @extra_collapser_args);
+ }
+ # Regular multi-object
+ else {
- my $alias = $self->{attrs}{alias};
- my $info = [];
+ # The rationale is - if this is the ::Row inflator itself, or an around()
+ # we do prune, because we expect it.
+ # If not the case - let the user deal with the full output themselves
+ # Warn them while we are at it so we get a better idea what is out there
+ # on the DarkPan
+ $self->{_result_inflator}{prune_null_branches} = do {
+ $res_class->isa('DBIx::Class::Row')
+ } ? 1 : 0 unless defined $self->{_result_inflator}{prune_null_branches};
+
+ unless ($self->{_result_inflator}{prune_null_branches}) {
+ carp_once (
+ "ResultClass $res_class does not inherit from DBIx::Class::Row and "
+ . 'therefore its inflate_result() will receive the full prefetched data '
+ . 'tree, without any branch definedness checks. This is a compatibility '
+ . 'measure which will eventually disappear entirely. Please refer to '
+ . 't/resultset/inflate_result_api.t for an exhaustive description of the '
+ . 'upcoming changes'
+ );
+ }
- my %collapse_pos;
+ ( $self->{_row_parser}{classic}{$self->{_result_inflator}{prune_null_branches}} ||= $rsrc->_mk_row_parser({
+ eval => 1,
+ inflate_map => $infmap,
+ selection => $attrs->{select},
+ collapse => $attrs->{collapse},
+ premultiplied => $attrs->{_main_source_premultiplied},
+ prune_null_branches => $self->{_result_inflator}{prune_null_branches},
+ }) )->($rows, @extra_collapser_args);
- my @const_keys;
+ $_ = $inflator_cref->($res_class, $rsrc, @$_) for @$rows;
+ }
- 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};
- }
- }
+ # 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
+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.
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);
}
# 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;
+
+ delete $self->{_result_inflator};
}
$self->_result_class;
}
=over 4
-=item Arguments: $cond, \%attrs??
+=item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
=item Return Value: $count
return $self->search(@_)->count if @_ and defined $_[0];
return scalar @{ $self->get_cache } if $self->get_cache;
- my $attrs = $self->_resolved_attrs_copy;
+ 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 = delete $attrs->{rows};
- my $offset = delete $attrs->{offset};
+ my ($rows, $offset) = delete @{$attrs}{qw/rows offset/};
my $crs;
if ($self->_has_resolved_attr (qw/collapse group_by/)) {
=over 4
-=item Arguments: $cond, \%attrs??
+=item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
-=item Return Value: $count_rs
+=item Return Value: L<$count_rs|DBIx::Class::ResultSetColumn>
=back
# overwrite the selector (supplied by the storage)
$tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $attrs);
$tmp_attrs->{as} = 'count';
- delete @{$tmp_attrs}{qw/columns _trailing_select/};
my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
my $sub_attrs = { %$attrs };
# extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
- delete @{$sub_attrs}{qw/collapse columns as select _prefetch_selector_range _trailing_select order_by for/};
+ delete @{$sub_attrs}{qw/collapse columns as select _prefetch_selector_range order_by for/};
- # if we multi-prefetch we group_by primary keys only as this is what we would
+ # 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 ( keys %{$attrs->{collapse}} ) {
- $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } ($rsrc->_pri_cols) ]
+ if ( $attrs->{collapse} ) {
+ $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
+ $rsrc->_identifying_column_set || $self->throw_exception(
+ 'Unable to construct a unique group_by criteria properly collapsing the '
+ . 'has_many prefetch before count()'
+ );
+ } ]
}
# Calculate subquery selector
my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
- my $sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
+ my $having_sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
+ my %seen_having;
# search for both a proper quoted qualified string, for a naive unquoted scalarref
# and if all fails for an utterly naive quoted scalar-with-function
- while ($sql =~ /
+ while ($having_sql =~ /
$rquote $sep $lquote (.+?) $rquote
|
[\s,] \w+ \. (\w+) [\s,]
|
[\s,] $lquote (.+?) $rquote [\s,]
/gx) {
- push @parts, ($1 || $2 || $3); # one of them matched if we got here
+ my $part = $1 || $2 || $3; # one of them matched if we got here
+ unless ($seen_having{$part}++) {
+ push @parts, $part;
+ }
}
}
=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 = shift;
if(@_) {
- $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
+ $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
}
- return @{ $self->get_cache } if $self->get_cache;
-
- my @obj;
-
- if (keys %{$self->_resolved_attrs->{collapse}}) {
- # 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
- $self->cursor->reset;
- 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 { $self->_construct_object(@$_) } $self->cursor->all;
+ delete @{$self}{qw/stashed_rows stashed_objects/};
+
+ if (my $c = $self->get_cache) {
+ return @$c;
}
- $self->set_cache(\@obj) if $self->{attrs}{cache};
+ $self->cursor->reset;
+
+ my $objs = $self->_construct_objects('fetch_all') || [];
- return @obj;
+ $self->set_cache($objs) if $self->{attrs}{cache};
+
+ return @$objs;
}
=head2 reset
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: $object | undef
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
=back
-Resets the resultset and returns an object for the first result (or C<undef>
-if the resultset is empty).
+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
my ($self, $op, $values) = @_;
my $rsrc = $self->result_source;
+ my $storage = $rsrc->schema->storage;
- # if a condition exists we need to strip all table qualifiers
- # if this is not possible we'll force a subquery below
- my $cond = $rsrc->schema->storage->_strip_cond_qualifiers ($self->{cond});
+ my $attrs = { %{$self->_resolved_attrs} };
- my $needs_group_by_subq = $self->_has_resolved_attr (qw/collapse group_by -join/);
- my $needs_subq = $needs_group_by_subq || (not defined $cond) || $self->_has_resolved_attr(qw/rows offset/);
+ my $join_classifications;
+ my $existing_group_by = delete $attrs->{group_by};
- if ($needs_group_by_subq or $needs_subq) {
+ # 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/)
+ );
- # make a new $rs selecting only the PKs (that's all we really need)
- my $attrs = $self->_resolved_attrs_copy;
+ # simplify the joinmap, so we can further decide if a subq is necessary
+ if (!$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} || {} };
+ }
+ }
- delete $attrs->{$_} for qw/collapse _collapse_order_by select _prefetch_selector_range as/;
- $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->_pri_cols) ];
+ # 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]{ $attrs->{from}[0]{-alias} }
+ );
- if ($needs_group_by_subq) {
- # make sure no group_by was supplied, or if there is one - make sure it matches
- # the columns compiled above perfectly. Anything else can not be sanely executed
- # on most databases so croak right then and there
+ 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,
+ )
+ );
- if (my $g = $attrs->{group_by}) {
- my @current_group_by = map
- { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
- @$g
- ;
+ # 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, $attrs);
- if (
- join ("\x00", sort @current_group_by)
- ne
- join ("\x00", sort @{$attrs->{columns}} )
- ) {
- $self->throw_exception (
- "You have just attempted a $op operation on a resultset which does group_by"
- . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
- . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
- . ' kind of queries. Please retry the operation with a modified group_by or'
- . ' without using one at all.'
- );
+ if (@$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 {
+ # 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} });
}
- else {
- $attrs->{group_by} = $attrs->{columns};
+
+ $guard = $storage->txn_scope_guard;
+
+ $cond = [];
+ for my $row ($subrs->cursor->all) {
+ push @$cond, { map
+ { $idcols->[$_] => $row->[$_] }
+ (0 .. $#$idcols)
+ };
}
}
-
- my $subrs = (ref $self)->new($rsrc, $attrs);
- return $self->result_source->storage->_subq_update_delete($subrs, $op, $values);
- }
- else {
- return $rsrc->storage->$op(
- $rsrc,
- $op eq 'update' ? $values : (),
- $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. Note that this will not run any accessor/set_column/update
-triggers, nor will it update any row object instances derived from this
+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>.
+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
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>.
+L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
=cut
unless ref $values eq 'HASH';
my $guard = $self->result_source->schema->txn_scope_guard;
- $_->update($values) for $self->all;
+ $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
$guard->commit;
return 1;
}
=item Arguments: none
-=item Return Value: $storage_rv
+=item Return Value: $underlying_storage_rv
=back
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 row object instances
+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>.
+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.
=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.
-For the arrayref of hashrefs style each hashref should be a structure suitable
-for submitting to a $resultset->create(...) method.
+Accepts either an arrayref of hashrefs or alternatively an arrayref of
+arrayrefs.
+
+=over
+
+=item NOTE
-In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
-to insert the data, as this is a faster method.
+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.
-Otherwise, each set of data is inserted into the database using
-L<DBIx::Class::ResultSet/create>, and the resulting objects are
-accumulated into an array. The array itself, or an array reference
-is returned depending on scalar or list context.
+=back
+
+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.
+
+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:
-Example: Assuming an Artist Class that has many CDs Classes relating:
+ $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' ],
+ ]);
- my $Artist_rs = $schema->resultset("Artist");
+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.
- ## Void Context Example
- $Artist_rs->populate([
+ $schema->resultset("Artist")->populate([
{ artistid => 4, name => 'Manufactured Crap', cds => [
{ title => 'My First CD', year => 2006 },
{ title => 'Yet More Tweeny-Pop crap', year => 2007 },
},
]);
- ## Array Context Example
- my ($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'
-
-For the arrayref of arrayrefs style, the first element should be a list of the
-fieldsnames to which the remaining elements are rows being inserted. For
-example:
-
- $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'],
- ]);
-
-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
# 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 = $data->[0];
## inherit the data locked in the conditions of the resultset
my ($rs_data) = $self->_merge_with_rscond({});
delete @{$rs_data}{@columns};
- my @inherit_cols = keys %$rs_data;
- my @inherit_data = values %$rs_data;
## do bulk insert on current row
$rsrc->storage->insert_bulk(
$rsrc,
- [@columns, @inherit_cols],
- [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
+ [@columns, keys %$rs_data],
+ [ map { [ @$_{@columns}, values %$rs_data ] } @$data ],
);
## do the has_many relationships
my ($self, $arg) = @_;
if (ref $arg eq 'ARRAY') {
- if (ref $arg->[0] eq 'HASH') {
+ if (!@$arg) {
+ return [];
+ }
+ elsif (ref $arg->[0] eq 'HASH') {
return $arg;
}
elsif (ref $arg->[0] eq 'ARRAY') {
=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
=cut
-# make a wizard good for both a scalar and a hashref
-my $mk_lazy_count_wizard = sub {
- require Variable::Magic;
-
- my $stash = { total_rs => shift };
- my $slot = shift; # only used by the hashref magic
-
- my $magic = Variable::Magic::wizard (
- data => sub { $stash },
-
- (!$slot)
- ? (
- # the scalar magic
- get => sub {
- # set value lazily, and dispell for good
- ${$_[0]} = $_[1]{total_rs}->count;
- Variable::Magic::dispell (${$_[0]}, $_[1]{magic_selfref});
- return 1;
- },
- set => sub {
- # an explicit set implies dispell as well
- # the unless() is to work around "fun and giggles" below
- Variable::Magic::dispell (${$_[0]}, $_[1]{magic_selfref})
- unless (caller(2))[3] eq 'DBIx::Class::ResultSet::pager';
- return 1;
- },
- )
- : (
- # the uvar magic
- fetch => sub {
- if ($_[2] eq $slot and !$_[1]{inactive}) {
- my $cnt = $_[1]{total_rs}->count;
- $_[0]->{$slot} = $cnt;
-
- # attempting to dispell in a fetch handle (works in store), seems
- # to invariable segfault on 5.10, 5.12, 5.13 :(
- # so use an inactivator instead
- #Variable::Magic::dispell (%{$_[0]}, $_[1]{magic_selfref});
- $_[1]{inactive}++;
- }
- return 1;
- },
- store => sub {
- if (! $_[1]{inactive} and $_[2] eq $slot) {
- #Variable::Magic::dispell (%{$_[0]}, $_[1]{magic_selfref});
- $_[1]{inactive}++
- unless (caller(2))[3] eq 'DBIx::Class::ResultSet::pager';
- }
- return 1;
- },
- ),
- );
-
- $stash->{magic_selfref} = $magic;
- weaken ($stash->{magic_selfref}); # this fails on 5.8.1
-
- return $magic;
-};
-
-# the tie class for 5.8.1
-{
- package # hide from pause
- DBIx::Class::__DBIC_LAZY_RS_COUNT__;
- use base qw/Tie::Hash/;
-
- sub FIRSTKEY { my $dummy = scalar keys %{$_[0]{data}}; each %{$_[0]{data}} }
- sub NEXTKEY { each %{$_[0]{data}} }
- sub EXISTS { exists $_[0]{data}{$_[1]} }
- sub DELETE { delete $_[0]{data}{$_[1]} }
- sub CLEAR { %{$_[0]{data}} = () }
- sub SCALAR { scalar %{$_[0]{data}} }
-
- sub TIEHASH {
- $_[1]{data} = {%{$_[1]{selfref}}};
- %{$_[1]{selfref}} = ();
- Scalar::Util::weaken ($_[1]{selfref});
- return bless ($_[1], $_[0]);
- };
-
- sub FETCH {
- if ($_[1] eq $_[0]{slot}) {
- my $cnt = $_[0]{data}{$_[1]} = $_[0]{total_rs}->count;
- untie %{$_[0]{selfref}};
- %{$_[0]{selfref}} = %{$_[0]{data}};
- return $cnt;
- }
- else {
- $_[0]{data}{$_[1]};
- }
- }
-
- sub STORE {
- $_[0]{data}{$_[1]} = $_[2];
- if ($_[1] eq $_[0]{slot}) {
- untie %{$_[0]{selfref}};
- %{$_[0]{selfref}} = %{$_[0]{data}};
- }
- $_[2];
- }
-}
-
sub pager {
my ($self) = @_;
return $self->{pager} if $self->{pager};
- if ($self->get_cache) {
- $self->throw_exception ('Pagers on cached resultsets are not supported');
- }
-
my $attrs = $self->{attrs};
if (!defined $attrs->{page}) {
$self->throw_exception("Can't create pager for non-paged rs");
# 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 $count_attrs->{$_} for qw/rows offset page pager/;
- my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
-
+ my $count_attrs = { %$attrs };
+ delete @{$count_attrs}{qw/rows offset page pager/};
-### the following may seem awkward and dirty, but it's a thought-experiment
-### necessary for future development of DBIx::DS. Do *NOT* change this code
-### before talking to ribasushi/mst
+ my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
- require Data::Page;
- my $pager = Data::Page->new(
- 0, #start with an empty set
+ 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},
);
-
- my $data_slot = 'total_entries';
-
- # Since we are interested in a cached value (once it's set - it's set), every
- # technique will detach from the magic-host once the time comes to fire the
- # ->count (or in the segfaulting case of >= 5.10 it will deactivate itself)
-
- if ($] < 5.008003) {
- # 5.8.1 throws 'Modification of a read-only value attempted' when one tries
- # to weakref the magic container :(
- # tested on 5.8.1
- tie (%$pager, 'DBIx::Class::__DBIC_LAZY_RS_COUNT__',
- { slot => $data_slot, total_rs => $total_rs, selfref => $pager }
- );
- }
- elsif ($] < 5.010) {
- # We can use magic on the hash value slot. It's interesting that the magic is
- # attached to the hash-slot, and does *not* stop working once I do the dummy
- # assignments after the cast()
- # tested on 5.8.3 and 5.8.9
- my $magic = $mk_lazy_count_wizard->($total_rs);
- Variable::Magic::cast ( $pager->{$data_slot}, $magic );
-
- # this is for fun and giggles
- $pager->{$data_slot} = -1;
- $pager->{$data_slot} = 0;
-
- # this does not work for scalars, but works with
- # uvar magic below
- #my %vals = %$pager;
- #%$pager = ();
- #%{$pager} = %vals;
- }
- else {
- # And the uvar magic
- # works on 5.10.1, 5.12.1 and 5.13.4 in its current form,
- # however see the wizard maker for more notes
- my $magic = $mk_lazy_count_wizard->($total_rs, $data_slot);
- Variable::Magic::cast ( %$pager, $magic );
-
- # still works
- $pager->{$data_slot} = -1;
- $pager->{$data_slot} = 0;
-
- # this now works
- my %vals = %$pager;
- %$pager = ();
- %{$pager} = %vals;
- }
-
- return $self->{pager} = $pager;
}
=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: $rowobject
+=item Return Value: L<$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 $values eq 'HASH');
my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
=item Arguments: none
-=item Return Value: \[ $sql, @bind ]
+=item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
=back
sub as_query {
my $self = shift;
- my $attrs = $self->_resolved_attrs_copy;
+ my $attrs = { %{ $self->_resolved_attrs } };
# For future use:
#
=over 4
-=item Arguments: \%vals, \%attrs?
+=item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
-=item Return Value: $rowobject
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
=back
=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
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.
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<new|DBIx::Class::Row/new>
-or L<insert|DBIx::Class::Row/insert> depending on how early in the
-L</create> process you need to intervene.
+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
=over 4
-=item Arguments: \%vals, \%attrs?
+=item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
-=item Return Value: $rowobject
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
=back
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 {
=over 4
-=item Arguments: \%col_values, { key => $unique_constraint }?
+=item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
-=item Return Value: $row_object
+=item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
=back
$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_values) >>.
+C<< $found_row->update (\%col_data) >>.
Takes an optional C<key> attribute to search on a specific unique constraint.
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 {
=over 4
-=item Arguments: \%col_values, { key => $unique_constraint }?
+=item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
-=item Return Value: $rowobject
+=item Return Value: L<$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_values) >>.
+C<< $found_row->update (\%col_data) >>.
For example:
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>.
+See also L</find>, L</find_or_create> and L</find_or_new>.
=cut
=item Arguments: none
-=item Return Value: \@cache_objects | undef
+=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
=over 4
-=item Arguments: $relationship_name
+=item Arguments: $rel_name
-=item Return Value: $resultset
+=item Return Value: L<$resultset|/search>
=back
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);
#XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
delete @{$attrs}{qw(result_class alias)};
- my $new_cache;
+ my $related_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 ];
- }
+ $related_cache = [ map
+ { @{$_->related_resultset($rel)->get_cache||[]} }
+ @$cache
+ ];
}
my $rel_source = $rsrc->related_source($rel);
where => $attrs->{where},
});
};
- $new->set_cache($new_cache) if $new_cache;
+ $new->set_cache($related_cache) if $related_cache;
$new;
};
}
my $me = $self->current_source_alias;
- return $self->search(
+ return $self->search({
"$me.modified" => $user->id,
- );
+ });
}
=cut
sub current_source_alias {
- my ($self) = @_;
-
- return ($self->{attrs} || {})->{alias} || 'me';
+ return (shift->{attrs} || {})->{alias} || 'me';
}
=head2 as_subselect_rs
=item Arguments: none
-=item Return Value: $resultset
+=item Return Value: L<$resultset|/search>
=back
return {%$attrs, from => $from, seen_join => $seen};
}
-# too many times we have to do $attrs = { %{$self->_resolved_attrs} }
-sub _resolved_attrs_copy {
- my $self = shift;
- return { %{$self->_resolved_attrs (@_)} };
-}
+# FIXME - this needs to go live in Schema with the tree walker... or
+# something
+my $inflatemap_checker;
+$inflatemap_checker = sub {
+ my ($rsrc, $relpaths) = @_;
+
+ my $rels;
+
+ for (@$relpaths) {
+ $_ =~ /^ ( [^\.]+ ) \. (.+) $/x
+ or next;
+
+ push @{$rels->{$1}}, $2;
+ }
+
+ for my $rel (keys %$rels) {
+ my $rel_rsrc = try {
+ $rsrc->related_source ($rel)
+ } catch {
+ $rsrc->throw_exception(sprintf(
+ "Inflation into non-existent relationship '%s' of '%s' requested, "
+ . "check the inflation specification (columns/as) ending in '...%s.%s'",
+ $rel,
+ $rsrc->source_name,
+ $rel,
+ ( sort { length($a) <=> length ($b) } @{$rels->{$rel}} )[0],
+ ))};
+
+ $inflatemap_checker->($rel_rsrc, $rels->{$rel});
+ }
+
+ return;
+};
sub _resolved_attrs {
my $self = shift;
my $source = $self->result_source;
my $alias = $attrs->{alias};
- # one last pass of normalization
- $self->_normalize_selection($attrs);
-
# default selection list
$attrs->{columns} = [ $source->columns ]
- unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as _trailing_select/;
+ unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
# merge selectors together
- for (qw/columns select as _trailing_select/) {
- $attrs->{$_} = $self->_merge_attr($attrs->{$_}, $attrs->{"+$_"})
+ for (qw/columns select as/) {
+ $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
if $attrs->{$_} or $attrs->{"+$_"};
}
if (my $cols = delete $attrs->{columns}) {
for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
if (ref $c eq 'HASH') {
- for my $as (keys %$c) {
+ for my $as (sort keys %$c) {
push @sel, $c->{$as};
push @as, $as;
}
if $attrs->{select};
# assume all unqualified selectors to apply to the current alias (legacy stuff)
- for (@sel) {
- $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_";
- }
+ $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
- # disqualify all $alias.col as-bits (collapser mandated)
- for (@as) {
- $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_;
- }
+ # 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
}
}
+ # validate the user-supplied 'as' chain
+ # folks get too confused by the (logical) exception message, need to
+ # go to some lengths to clarify the text
+ #
+ # FIXME - this needs to go live in Schema with the tree walker... or
+ # something
+ $inflatemap_checker->($source, \@as);
+
$attrs->{select} = \@sel;
$attrs->{as} = \@as;
}
else {
# distinct affects only the main selection part, not what prefetch may
- # add below. However trailing is not yet a part of the selection as
- # prefetch must insert before it
+ # add below.
$attrs->{group_by} = $source->storage->_group_over_selection (
$attrs->{from},
- [ @{$attrs->{select}||[]}, @{$attrs->{_trailing_select}||[]} ],
+ $attrs->{select},
$attrs->{order_by},
);
}
}
- $attrs->{collapse} ||= {};
- if ($attrs->{prefetch}) {
- my $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} );
+ # generate selections based on the prefetch helper
+ my $prefetch;
+ $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
+ if defined $attrs->{prefetch};
+
+ if ($prefetch) {
- my $prefetch_ordering = [];
+ $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
+ if $attrs->{_dark_selector};
+
+ $attrs->{collapse} = 1;
# this is a separate structure (we don't look in {from} directly)
# as the resolver needs to shift things off the lists to work
}
}
- my @prefetch =
- $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
+ my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map );
# we need to somehow mark which columns came from prefetch
if (@prefetch) {
push @{ $attrs->{select} }, (map { $_->[0] } @prefetch);
push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
+ }
- push( @{$attrs->{order_by}}, @$prefetch_ordering );
- $attrs->{_collapse_order_by} = \@$prefetch_ordering;
+ if ( ! List::Util::first { $_ =~ /\./ } @{$attrs->{as}} ) {
+ $attrs->{_single_resultclass_inflation} = 1;
+ $attrs->{collapse} = 0;
}
+ # run through the resulting joinstructure (starting from our current slot)
+ # and unset collapse if proven unnesessary
+ #
+ # also while we are at it find out if the current root source has
+ # been premultiplied by previous related_source chaining
+ #
+ # this allows to predict whether a root object with all other relation
+ # data set to NULL is in fact unique
+ if ($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;
+ }
+
+ # 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;
+ }
+ }
+ }
- push @{ $attrs->{select} }, @{$attrs->{_trailing_select}}
- if $attrs->{_trailing_select};
+ else {
+ # if we can not analyze the from - err on the side of safety
+ $attrs->{_main_source_premultiplied} = 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
$position++;
}
my ($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 $seen_keys->{$import_key}) {
push( @{$orig}, $import_element );
$seen_keys->{$import_key} = 1; # don't merge the same key twice
}
- return $orig;
+ return @$orig ? $orig : ();
}
{
my $to_serialize = { %$self };
# A cursor in progress can't be serialized (and would make little sense anyway)
- delete $to_serialize->{cursor};
+ # the parser can be regenerated (and can't be serialized)
+ delete @{$to_serialize}{qw/cursor _row_parser _result_inflator/};
+
+ # 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);
}
}
}
+1;
+
+__END__
+
# XXX: FIXME: Attributes docs need clearing up
=head1 ATTRIBUTES
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: \@columns
+=item Value: \@columns | \%columns | $column
=back
=back
-=head2 +as
-
-=over 4
-
-Indicates additional column names for those added via L</+select>. See L</as>.
-
-=back
-
=head2 as
=over 4
You can create your own accessors if required - see
L<DBIx::Class::Manual::Cookbook> for details.
+=head2 +as
+
+=over 4
+
+Indicates additional column names for those added via L</+select>. See L</as>.
+
+=back
+
=head2 join
=over 4
will return a set of all artists that have both a cd with title 'Down
to Earth' and a cd with title 'Popular'.
-If you want to fetch related objects from other tables as well, see C<prefetch>
+If you want to fetch related objects from other tables as well, see L</prefetch>
below.
+ NOTE: An internal join-chain pruner will discard certain joins while
+ constructing the actual SQL query, as long as the joins in question do not
+ affect the retrieved result. This for example includes 1:1 left joins
+ that are not part of the restriction specification (WHERE/HAVING) nor are
+ a part of the query selection.
+
For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
-=head2 prefetch
+=head2 collapse
=over 4
-=item Value: ($rel_name | \@rel_names | \%rel_names)
+=item Value: (0 | 1)
=back
-Contains one or more relationships that should be fetched along with
-the main query (when they are accessed afterwards the data will
-already be available, without extra queries to the database). This is
-useful for when you know you will need the related objects, because it
-saves at least one query:
-
- my $rs = $schema->resultset('Tag')->search(
- undef,
- {
- prefetch => {
- cd => 'artist'
- }
- }
- );
+When set to a true value, indicates that any rows fetched from joined has_many
+relationships are to be aggregated into the corresponding "parent" object. For
+example, the resultset:
-The initial search results in SQL like the following:
+ my $rs = $schema->resultset('CD')->search({}, {
+ '+columns' => [ qw/ tracks.title tracks.position / ],
+ join => 'tracks',
+ collapse => 1,
+ });
- SELECT tag.*, cd.*, artist.* FROM tag
- JOIN cd ON tag.cd = cd.cdid
- JOIN artist ON cd.artist = artist.artistid
+While executing the following query:
-L<DBIx::Class> has no need to go back to the database when we access the
-C<cd> or C<artist> relationships, which saves us two SQL statements in this
-case.
+ SELECT me.*, tracks.title, tracks.position
+ FROM cd me
+ LEFT JOIN track tracks
+ ON tracks.cdid = me.cdid
-Simple prefetches will be joined automatically, so there is no need
-for a C<join> attribute in the above search.
+Will return only as many objects as there are rows in the CD source, even
+though the result of the query may span many rows. Each of these CD objects
+will in turn have multiple "Track" objects hidden behind the has_many
+generated accessor C<tracks>. Without C<< collapse => 1 >>, the return values
+of this resultset would be as many CD objects as there are tracks (a "Cartesian
+product"), with each CD object containing exactly one of all fetched Track data.
-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 associated
-with that artist is given below (assuming many-to-many from artists to tags):
+When a collapse is requested on a non-ordered resultset, an order by some
+unique part of the main source (the left-most table) is inserted automatically.
+This is done so that the resultset is allowed to be "lazy" - calling
+L<< $rs->next|/next >> will fetch only as many rows as it needs to build the next
+object with all of its related data.
- my $rs = $schema->resultset('Artist')->search(
- undef,
- {
- prefetch => [
- { cds => 'tracks' },
- { artist_tags => 'tags' }
- ]
- }
- );
+If an L</order_by> is already declared, and orders the resultset in a way that
+makes collapsing as described above impossible (e.g. C<< ORDER BY
+has_many_rel.column >> or C<ORDER BY RANDOM()>), DBIC will automatically
+switch to "eager" mode and slurp the entire resultset before consturcting the
+first object returned by L</next>.
+Setting this attribute on a resultset that does not join any has_many
+relations is a no-op.
-B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
-attributes will be ignored.
+For a more in-depth discussion, see L</PREFETCHING>.
-B<CAVEATs>: Prefetch does a lot of deep magic. As such, it may not behave
-exactly as you might expect.
+=head2 prefetch
=over 4
-=item *
+=item Value: ($rel_name | \@rel_names | \%rel_names)
-Prefetch uses the L</cache> to populate the prefetched relationships. This
-may or may not be what you want.
+=back
-=item *
+This attribute is a shorthand for specifying a L</join> spec, adding all
+columns from the joined related sources as L</+columns> and setting
+L</collapse> to a true value. For example, the following two queries are
+equivalent:
-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 $rs = $schema->resultset('Artist')->search({}, {
+ prefetch => { cds => ['genre', 'tracks' ] },
+ });
- my $artist_rs = $schema->resultset('Artist')->search({
- 'cds.year' => 2008,
- }, {
- join => 'cds',
+and
+
+ my $rs = $schema->resultset('Artist')->search({}, {
+ join => { cds => ['genre', 'tracks' ] },
+ collapse => 1,
+ '+columns' => [
+ (map
+ { +{ "cds.$_" => "cds.$_" } }
+ $schema->source('Artist')->related_source('cds')->columns
+ ),
+ (map
+ { +{ "cds.genre.$_" => "genre.$_" } }
+ $schema->source('Artist')->related_source('cds')->related_source('genre')->columns
+ ),
+ (map
+ { +{ "cds.tracks.$_" => "tracks.$_" } }
+ $schema->source('Artist')->related_source('cds')->related_source('tracks')->columns
+ ),
+ ],
});
- my $count = $artist_rs->first->cds->count;
+Both producing the following SQL:
+
+ SELECT me.artistid, me.name, me.rank, me.charfield,
+ cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track,
+ genre.genreid, genre.name,
+ tracks.trackid, tracks.cd, tracks.position, tracks.title, tracks.last_updated_on, tracks.last_updated_at
+ FROM artist me
+ LEFT JOIN cd cds
+ ON cds.artist = me.artistid
+ LEFT JOIN genre genre
+ ON genre.genreid = cds.genreid
+ LEFT JOIN track tracks
+ ON tracks.cd = cds.cdid
+ ORDER BY me.artistid
+
+While L</prefetch> implies a L</join>, it is ok to mix the two together, as
+the arguments are properly merged and generally do the right thing. For
+example, you may want to do the following:
+
+ my $artists_and_cds_without_genre = $schema->resultset('Artist')->search(
+ { 'genre.genreid' => undef },
+ {
+ join => { cds => 'genre' },
+ prefetch => 'cds',
+ }
+ );
- my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
+Which generates the following SQL:
- my $prefetch_count = $artist_rs_prefetch->first->cds->count;
+ SELECT me.artistid, me.name, me.rank, me.charfield,
+ cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track
+ FROM artist me
+ LEFT JOIN cd cds
+ ON cds.artist = me.artistid
+ LEFT JOIN genre genre
+ ON genre.genreid = cds.genreid
+ WHERE genre.genreid IS NULL
+ ORDER BY me.artistid
- cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
+For a more in-depth discussion, see L</PREFETCHING>.
-that cmp_ok() may or may not pass depending on the datasets involved. This
-behavior may or may not survive the 0.09 transition.
+=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
=over 4
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
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.
+For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
+
=back
=head2 cache
=over 4
-=item Value: ( 'update' | 'shared' )
+=item Value: ( 'update' | 'shared' | \$scalar )
=back
Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
-... FOR SHARED.
+... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
+query.
-=cut
+=head1 PREFETCHING
+
+DBIx::Class supports arbitrary related data prefetching from multiple related
+sources. Any combination of relationship types and column sets are supported.
+If L<collapsing|/collapse> is requested, there is an additional requirement of
+selecting enough data to make every individual object uniquely identifiable.
+
+Here are some more involved examples, based on the following relationship map:
+
+ # Assuming:
+ My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
+ My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
+ 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('Tag')->search(
+ undef,
+ {
+ prefetch => {
+ cd => 'artist'
+ }
+ }
+ );
+
+The initial search results in SQL like the following:
+
+ SELECT tag.*, cd.*, artist.* FROM tag
+ JOIN cd ON tag.cd = cd.cdid
+ JOIN artist ON cd.artist = artist.artistid
+
+L<DBIx::Class> has no need to go back to the database when we access the
+C<cd> or C<artist> relationships, which saves us two SQL statements in this
+case.
+
+Simple prefetches will be joined automatically, so there is no need
+for a C<join> attribute in the above search.
+
+The L</prefetch> attribute can be used with 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.
+
+ 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
+ ]
+ }
+ );
+
+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.
+
+=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
+
+=head1 DBIC BIND VALUES
+
+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:
+
+=over 4
+
+=item dbd_attrs
+
+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.)
+
+If this is specified, all other bind options described below are ignored.
+
+=item sqlt_datatype
+
+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>.
+
+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.)
+
+=item sqlt_size
+
+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
+
+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.
-1;