use strict;
use warnings;
use overload
- '0+' => 'count',
+ '0+' => \&count,
+ 'bool' => sub { 1; },
fallback => 1;
+use Carp::Clan qw/^DBIx::Class/;
use Data::Page;
+use Storable;
+use DBIx::Class::ResultSetColumn;
+use base qw/DBIx::Class/;
+
+__PACKAGE__->load_components(qw/AccessorGroup/);
+__PACKAGE__->mk_group_accessors('simple' => qw/result_source result_class/);
=head1 NAME
-DBIX::Class::ResultSet - Responsible for fetching and creating resultset.
+DBIx::Class::ResultSet - Responsible for fetching and creating resultset.
-=head1 SYNOPSIS;
+=head1 SYNOPSIS
-$rs=MyApp::DB::Class->search(registered=>1);
+ my $rs = $schema->resultset('User')->search(registered => 1);
+ my @rows = $schema->resultset('CD')->search(year => 2005);
=head1 DESCRIPTION
-The resultset is also known as an iterator.
+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.
+
+In the examples below, the following table classes are used:
+
+ 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;
+
+ 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;
=head1 METHODS
+=head2 new
+
=over 4
-=item new <db_class> <attrs>
+=item Arguments: $source, \%$attrs
+
+=item Return Value: $rs
+
+=back
+
+The resultset constructor. Takes a source object (usually a
+L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
+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:
+
+ my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
-The resultset constructor. Takes a db class and an
-attribute hash (see below for more info on attributes)
+IMPORTANT: If called on an object, proxies to new_result instead so
+
+ my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
+
+will return a CD object, not a ResultSet.
=cut
sub new {
- my ($class, $db_class, $attrs) = @_;
- #use Data::Dumper; warn Dumper(@_);
- $class = ref $class if ref $class;
- $attrs = { %{ $attrs || {} } };
- my %seen;
- $attrs->{cols} ||= [ map { "me.$_" } $db_class->_select_columns ];
- $attrs->{from} ||= [ { 'me' => $db_class->_table_name } ];
- if ($attrs->{join}) {
- foreach my $j (ref $attrs->{join} eq 'ARRAY'
- ? (@{$attrs->{join}}) : ($attrs->{join})) {
- if (ref $j eq 'HASH') {
- $seen{$_} = 1 foreach keys %$j;
- } else {
- $seen{$j} = 1;
- }
- }
- push(@{$attrs->{from}}, $db_class->_resolve_join($attrs->{join}, 'me'));
- }
- foreach my $pre (@{$attrs->{prefetch} || []}) {
- push(@{$attrs->{from}}, $db_class->_resolve_join($pre, 'me'))
- unless $seen{$pre};
- push(@{$attrs->{cols}},
- map { "$pre.$_" }
- $db_class->_relationships->{$pre}->{class}->_select_columns);
- }
- my $new = {
- source => $db_class,
- cols => $attrs->{cols},
+ my $class = shift;
+ return $class->new_result(@_) if ref $class;
+
+ my ($source, $attrs) = @_;
+ #weaken $source;
+
+ if ($attrs->{page}) {
+ $attrs->{rows} ||= 10;
+ $attrs->{offset} ||= 0;
+ $attrs->{offset} += ($attrs->{rows} * ($attrs->{page} - 1));
+ }
+
+ $attrs->{alias} ||= 'me';
+
+ my $self = {
+ result_source => $source,
+ result_class => $attrs->{result_class} || $source->result_class,
cond => $attrs->{where},
- from => $attrs->{from},
count => undef,
pager => undef,
- attrs => $attrs };
- bless ($new, $class);
- $new->pager if ($attrs->{page});
- return $new;
+ attrs => $attrs
+ };
+
+ bless $self, $class;
+
+ return $self;
}
-=item search
+=head2 search
+
+=over 4
+
+=item Arguments: $cond, \%attrs?
+
+=item Return Value: $resultset (scalar context), @row_objs (list context)
+
+=back
+
+ my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
+ my $new_rs = $cd_rs->search({ year => 2005 });
+
+ my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
+ # year = 2005 OR year = 2004
- my @obj = $rs->search({ foo => 3 }); # "... WHERE foo = 3"
- my $new_rs = $rs->search({ foo => 3 });
-
If you need to pass in additional attributes but no additional condition,
-call it as ->search(undef, \%attrs);
-
- my @all = $class->search({}, { cols => [qw/foo bar/] }); # "SELECT foo, bar FROM $class_table"
+call it as C<search(undef, \%attrs)>.
+
+ # "SELECT name, artistid FROM $artist_table"
+ my @all_artists = $schema->resultset('Artist')->search(undef, {
+ columns => [qw/name artistid/],
+ });
+
+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>.
=cut
sub search {
my $self = shift;
+ my $rs = $self->search_rs( @_ );
+ return (wantarray ? $rs->all : $rs);
+}
+
+=head2 search_rs
+
+=over 4
+
+=item Arguments: $cond, \%attrs?
+
+=item Return Value: $resultset
+
+=back
+
+This method does the same exact thing as search() except it will
+always return a resultset, even in list context.
+
+=cut
+
+sub search_rs {
+ my $self = shift;
+
+ my $rows;
- #use Data::Dumper;warn Dumper(@_);
+ unless (@_) { # no search, effectively just a clone
+ $rows = $self->get_cache;
+ }
+
+ 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 $attrs = { %{$self->{attrs}} };
- if (@_ > 1 && ref $_[$#_] eq 'HASH') {
- $attrs = { %{ pop(@_) } };
+ 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 $where = ((@_ == 1 || ref $_[0] eq "HASH") ? shift : {@_});
+ 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
+ );
+
if (defined $where) {
- $where = (defined $attrs->{where}
- ? { '-and' => [ $where, $attrs->{where} ] }
- : $where);
- $attrs->{where} = $where;
+ $new_attrs->{where} = (
+ defined $new_attrs->{where}
+ ? { '-and' => [
+ map {
+ ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
+ } $where, $new_attrs->{where}
+ ]
+ }
+ : $where);
}
- my $rs = $self->new($self->{source}, $attrs);
+ if (defined $cond) {
+ $new_attrs->{where} = (
+ defined $new_attrs->{where}
+ ? { '-and' => [
+ map {
+ ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
+ } $cond, $new_attrs->{where}
+ ]
+ }
+ : $cond);
+ }
- return (wantarray ? $rs->all : $rs);
+ if (defined $having) {
+ $new_attrs->{having} = (
+ defined $new_attrs->{having}
+ ? { '-and' => [
+ map {
+ ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
+ } $having, $new_attrs->{having}
+ ]
+ }
+ : $having);
+ }
+
+ my $rs = (ref $self)->new($self->result_source, $new_attrs);
+ if ($rows) {
+ $rs->set_cache($rows);
+ }
+ return $rs;
}
-=item search_literal
- my @obj = $rs->search_literal($literal_where_cond, @bind);
- my $new_rs = $rs->search_literal($literal_where_cond, @bind);
+=head2 search_literal
+
+=over 4
+
+=item Arguments: $sql_fragment, @bind_values
+
+=item Return Value: $resultset (scalar context), @row_objs (list context)
+
+=back
+
+ my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
+ my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
Pass a literal chunk of SQL to be added to the conditional part of the
-resultset
+resultset query.
+
+=cut
-=cut
sub search_literal {
my ($self, $cond, @vals) = @_;
my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {});
return $self->search(\$cond, $attrs);
}
-=item cursor
+=head2 find
+
+=over 4
+
+=item Arguments: @values | \%cols, \%attrs?
+
+=item Return Value: $row_object
+
+=back
+
+Finds a row based on its primary key or unique constraint. 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:
-Return a storage driven cursor to the given resultset.
+ my $cd = $schema->resultset('CD')->find(
+ {
+ artist => 'Massive Attack',
+ title => 'Mezzanine',
+ },
+ { key => 'cd_artist_title' }
+ );
+
+If the C<key> is specified as C<primary>, it searches only on the primary key.
+
+If no C<key> is specified, it searches on all unique constraints defined on the
+source, including the primary key.
+
+If your table does not have a primary key, you B<must> provide a value for the
+C<key> attribute matching one of the unique constraints on the source.
+
+See also L</find_or_create> and L</update_or_create>. For information on how to
+declare unique constraints, see
+L<DBIx::Class::ResultSource/add_unique_constraint>.
=cut
-sub cursor {
- my ($self) = @_;
- my ($source, $attrs) = @{$self}{qw/source attrs/};
- if ($attrs->{page}) {
- $attrs->{rows} = $self->pager->entries_per_page;
- $attrs->{offset} = $self->pager->skipped;
+sub find {
+ 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;
+
+ # Parse out a hashref from input
+ my $input_query;
+ if (ref $_[0] eq 'HASH') {
+ $input_query = { %{$_[0]} };
+ }
+ elsif (@_ == @cols) {
+ $input_query = {};
+ @{$input_query}{@cols} = @_;
+ }
+ else {
+ # Compatibility: Allow e.g. find(id => $value)
+ carp "Find by key => value deprecated; please use a hashref instead";
+ $input_query = {@_};
}
- return $self->{cursor}
- ||= $source->storage->select($self->{from}, $self->{cols},
- $attrs->{where},$attrs);
-}
-=item search_like
-
-Identical to search except defaults to 'LIKE' instead of '=' in condition
-
-=cut
+ my (%related, $info);
-sub search_like {
- my $class = shift;
- my $attrs = { };
- if (@_ > 1 && ref $_[$#_] eq 'HASH') {
- $attrs = pop(@_);
+ foreach my $key (keys %$input_query) {
+ if (ref($input_query->{$key})
+ && ($info = $self->result_source->relationship_info($key))) {
+ my $rel_q = $self->result_source->resolve_condition(
+ $info->{cond}, delete $input_query->{$key}, $key
+ );
+ die "Can't handle OR join condition in find" if ref($rel_q) eq 'ARRAY';
+ @related{keys %$rel_q} = values %$rel_q;
+ }
+ }
+ if (my @keys = keys %related) {
+ @{$input_query}{@keys} = values %related;
+ }
+
+ my @unique_queries = $self->_unique_queries($input_query, $attrs);
+
+ # 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 = @unique_queries
+ ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
+ : $self->_add_alias($input_query, $alias);
+
+ # Run the query
+ if (keys %$attrs) {
+ my $rs = $self->search($query, $attrs);
+ return keys %{$rs->_resolved_attrs->{collapse}} ? $rs->next : $rs->single;
+ }
+ else {
+ return keys %{$self->_resolved_attrs->{collapse}}
+ ? $self->search($query)->next
+ : $self->single($query);
}
- my $query = ref $_[0] eq "HASH" ? { %{shift()} }: {@_};
- $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
- return $class->search($query, { %$attrs });
}
-=item slice <first> <last>
+# _add_alias
+#
+# Add the specified alias to the specified query hash. A copy is made so the
+# original query is not modified.
-return a number of elements from the given resultset.
+sub _add_alias {
+ my ($self, $query, $alias) = @_;
-=cut
+ my %aliased = %$query;
+ foreach my $col (grep { ! m/\./ } keys %aliased) {
+ $aliased{"$alias.$col"} = delete $aliased{$col};
+ }
-sub slice {
- my ($self, $min, $max) = @_;
- my $attrs = { %{ $self->{attrs} || {} } };
- $self->{source}->throw("Can't slice without where") unless $attrs->{where};
- $attrs->{offset} = $min;
- $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
- my $slice = $self->new($self->{source}, $attrs);
- return (wantarray ? $slice->all : $slice);
+ return \%aliased;
}
-=item next
+# _unique_queries
+#
+# Build a list of queries which satisfy unique constraints.
-Returns the next element in this resultset.
+sub _unique_queries {
+ my ($self, $query, $attrs) = @_;
-=cut
+ my @constraint_names = exists $attrs->{key}
+ ? ($attrs->{key})
+ : $self->result_source->unique_constraint_names;
-sub next {
- my ($self) = @_;
- my @row = $self->cursor->next;
- return unless (@row);
- return $self->_construct_object(@row);
-}
+ 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);
-sub _construct_object {
- my ($self, @row) = @_;
- my @cols = @{ $self->{attrs}{cols} };
- s/^me\.// for @cols;
- @cols = grep { /\(/ or ! /\./ } @cols;
- my $new;
- unless ($self->{attrs}{prefetch}) {
- $new = $self->{source}->_row_to_object(\@cols, \@row);
- } else {
- my @main = splice(@row, 0, scalar @cols);
- $new = $self->{source}->_row_to_object(\@cols, \@main);
- PRE: foreach my $pre (@{$self->{attrs}{prefetch}}) {
- my $rel_obj = $self->{source}->_relationships->{$pre};
- my $pre_class = $self->{source}->resolve_class($rel_obj->{class});
- my @pre_cols = $pre_class->_select_columns;
- my @vals = splice(@row, 0, scalar @pre_cols);
- my $fetched = $pre_class->_row_to_object(\@pre_cols, \@vals);
- $self->{source}->throw("No accessor for prefetched $pre")
- unless defined $rel_obj->{attrs}{accessor};
- if ($rel_obj->{attrs}{accessor} eq 'single') {
- foreach my $pri ($rel_obj->{class}->primary_columns) {
- unless (defined $fetched->get_column($pri)) {
- undef $fetched;
- last;
- }
- }
- $new->{_relationship_data}{$pre} = $fetched;
- } elsif ($rel_obj->{attrs}{accessor} eq 'filter') {
- $new->{_inflated_column}{$pre} = $fetched;
- } else {
- $self->{source}->throw("Don't know how to store prefetched $pre");
- }
- }
+ my $num_query = scalar keys %$unique_query;
+ next unless $num_query;
+
+ # XXX: Assuming quite a bit about $self->{attrs}{where}
+ my $num_cols = scalar @unique_cols;
+ my $num_where = exists $self->{attrs}{where}
+ ? scalar keys %{ $self->{attrs}{where} }
+ : 0;
+ push @unique_queries, $unique_query
+ if $num_query + $num_where == $num_cols;
}
- $new = $self->{attrs}{record_filter}->($new)
- if exists $self->{attrs}{record_filter};
- return $new;
+
+ return @unique_queries;
}
-=item count
+# _build_unique_query
+#
+# Constrain the specified query hash based on the specified column names.
-Performs an SQL count with the same query as the resultset was built
-with to find the number of elements. If passed arguments, does a search
-on the resultset and counts the results of that.
+sub _build_unique_query {
+ my ($self, $query, $unique_cols) = @_;
+
+ return {
+ map { $_ => $query->{$_} }
+ grep { exists $query->{$_} }
+ @$unique_cols
+ };
+}
+
+=head2 search_related
+
+=over 4
+
+=item Arguments: $rel, $cond, \%attrs?
+
+=item Return Value: $new_resultset
+
+=back
+
+ $new_rs = $cd_rs->search_related('artist', {
+ name => 'Emo-R-Us',
+ });
+
+Searches the specified relationship, optionally specifying a condition and
+attributes for matching records. See L</ATTRIBUTES> for more information.
=cut
-sub count {
- my $self = shift;
- return $self->search(@_)->count if @_ && defined $_[0];
- my $attrs = { %{ $self->{attrs} } };
- unless ($self->{count}) {
- # offset and order by are not needed to count
- delete $attrs->{$_} for qw/offset order_by/;
-
- my @cols = 'COUNT(*)';
- $self->{count} = $self->{source}->storage->select_single(
- $self->{from}, \@cols, $self->{cond}, $attrs);
- }
- return 0 unless $self->{count};
- return $self->{pager}->entries_on_this_page if ($self->{pager});
- return ( $attrs->{rows} && $attrs->{rows} < $self->{count} )
- ? $attrs->{rows}
- : $self->{count};
+sub search_related {
+ return shift->related_resultset(shift)->search(@_);
}
-=item count_literal
+=head2 cursor
-Calls search_literal with the passed arguments, then count
+=over 4
-=cut
+=item Arguments: none
-sub count_literal { shift->search_literal(@_)->count; }
+=item Return Value: $cursor
-=item all
+=back
-Returns all elements in the resultset. Is called implictly if the search
-method is used in list context.
+Returns a storage-driven cursor to the given resultset. See
+L<DBIx::Class::Cursor> for more information.
=cut
-sub all {
+sub cursor {
my ($self) = @_;
- return map { $self->_construct_object(@$_); }
- $self->cursor->all;
+
+ my $attrs = { %{$self->_resolved_attrs} };
+ return $self->{cursor}
+ ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
+ $attrs->{where},$attrs);
}
-=item reset
+=head2 single
+
+=over 4
+
+=item Arguments: $cond?
+
+=item Return Value: $row_object?
+
+=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.
-Reset this resultset's cursor, so you can iterate through the elements again.
+Can optionally take an additional condition *only* - this is a fast-code-path
+method; if you need to add extra joins or similar call ->search and then
+->single without a condition on the $rs returned from that.
=cut
-sub reset {
- my ($self) = @_;
- $self->cursor->reset;
- return $self;
+sub single {
+ my ($self, $where) = @_;
+ my $attrs = { %{$self->_resolved_attrs} };
+ if ($where) {
+ if (defined $attrs->{where}) {
+ $attrs->{where} = {
+ '-and' =>
+ [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
+ $where, delete $attrs->{where} ]
+ };
+ } else {
+ $attrs->{where} = $where;
+ }
+ }
+
+# XXX: Disabled since it doesn't infer uniqueness in all cases
+# unless ($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(
+ $attrs->{from}, $attrs->{select},
+ $attrs->{where}, $attrs
+ );
+
+ return (@data ? $self->_construct_object(@data) : ());
}
-=item first
+# _is_unique_query
+#
+# Try to determine if the specified query is guaranteed to be unique, based on
+# the declared unique constraints.
-resets the resultset and returns the first element.
+sub _is_unique_query {
+ my ($self, $query) = @_;
-=cut
+ my $collapsed = $self->_collapse_query($query);
+ my $alias = $self->{attrs}{alias};
-sub first {
- return $_[0]->reset->next;
+ 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 { $_ != 1 } values %seen;
+ }
+
+ return 0;
}
-=item delete
+# _collapse_query
+#
+# Recursively collapse the query, accumulating values for each column.
-Deletes all elements in the resultset.
+sub _collapse_query {
+ my ($self, $query, $collapsed) = @_;
-=cut
+ $collapsed ||= {};
-sub delete {
- my ($self) = @_;
- $_->delete for $self->all;
- return 1;
+ 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}++;
+ }
+ }
+ }
+
+ return $collapsed;
}
-*delete_all = \&delete; # Yeah, yeah, yeah ...
+=head2 get_column
+
+=over 4
+
+=item Arguments: $cond?
-=item pager
+=item Return Value: $resultsetcolumn
-Returns a L<Data::Page> object for the current resultset. Only makes
-sense for queries with page turned on.
+=back
+
+ my $max_length = $rs->get_column('length')->max;
+
+Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
=cut
-sub pager {
- my ($self) = @_;
- my $attrs = $self->{attrs};
- delete $attrs->{offset};
- my $rows_per_page = delete $attrs->{rows} || 10;
- $self->{pager} ||= Data::Page->new(
- $self->count, $rows_per_page, $attrs->{page} || 1);
- $attrs->{rows} = $rows_per_page;
- return $self->{pager};
+sub get_column {
+ my ($self, $column) = @_;
+ my $new = DBIx::Class::ResultSetColumn->new($self, $column);
+ return $new;
}
-=item page <page>
+=head2 search_like
+
+=over 4
+
+=item Arguments: $cond, \%attrs?
+
+=item Return Value: $resultset (scalar context), @row_objs (list context)
+
+=back
+
+ # WHERE title LIKE '%blue%'
+ $cd_rs = $rs->search_like({ title => '%blue%'});
-Returns a new resultset representing a given page.
+Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
+that this is simply a convenience method. You most likely want to use
+L</search> with specific operators.
+
+For more information, see L<DBIx::Class::Manual::Cookbook>.
=cut
-sub page {
- my ($self, $page) = @_;
- my $attrs = $self->{attrs};
- $attrs->{page} = $page;
- return $self->new($self->{source}, $attrs);
+sub search_like {
+ my $class = shift;
+ my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
+ my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
+ $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
+ return $class->search($query, { %$attrs });
}
-=back
+=head2 slice
+
+=over 4
+
+=item Arguments: $first, $last
-=head1 Attributes
+=item Return Value: $resultset (scalar context), @row_objs (list context)
+
+=back
+
+Returns a resultset or object list representing a subset of elements from the
+resultset slice is called on. Indexes are from 0, i.e., to get the first
+three records, call:
+
+ my ($one, $two, $three) = $rs->slice(0, 2);
+
+=cut
+
+sub slice {
+ my ($self, $min, $max) = @_;
+ my $attrs = {}; # = { %{ $self->{attrs} || {} } };
+ $attrs->{offset} = $self->{attrs}{offset} || 0;
+ $attrs->{offset} += $min;
+ $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
+ return $self->search(undef(), $attrs);
+ #my $slice = (ref $self)->new($self->result_source, $attrs);
+ #return (wantarray ? $slice->all : $slice);
+}
-The resultset is responsible for handling the various attributes that
-can be passed in with the search functions. Here's an overview of them:
+=head2 next
=over 4
-=item order_by
+=item Arguments: none
+
+=item Return Value: $result?
-Which column to order the results by.
+=back
+
+Returns the next element in the resultset (C<undef> is there is none).
-=item cols
+Can be used to efficiently iterate over records in the resultset:
-Which cols should be retrieved on the first search.
+ my $rs = $schema->resultset('CD')->search;
+ while (my $cd = $rs->next) {
+ print $cd->title;
+ }
-=item join
+Note that you need to store the resultset object, and call C<next> on it.
+Calling C<< resultset('Table')->next >> repeatedly will always return the
+first record from the resultset.
-Contains a list of relations that should be joined for this query. Can also
-contain a hash referece to refer to that relation's relations.
+=cut
-=item from
+sub next {
+ my ($self) = @_;
+ if (my $cache = $self->get_cache) {
+ $self->{all_cache_position} ||= 0;
+ return $cache->[$self->{all_cache_position}++];
+ }
+ if ($self->{attrs}{cache}) {
+ $self->{all_cache_position} = 1;
+ return ($self->all)[0];
+ }
+ my @row = (
+ exists $self->{stashed_row}
+ ? @{delete $self->{stashed_row}}
+ : $self->cursor->next
+ );
+ return unless (@row);
+ return $self->_construct_object(@row);
+}
-This attribute can contain a arrayref of elements. each element can be another
-arrayref, to nest joins, or it can be a hash which represents the two sides
-of the join.
+sub _construct_object {
+ my ($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 $new;
+}
-*NOTE* Use this on your own risk. This allows you to shoot your foot off!
+sub _collapse_result {
+ my ($self, $as, $row, $prefix) = @_;
+
+ my %const;
+ my @copy = @$row;
+
+ foreach my $this_as (@$as) {
+ my $val = shift @copy;
+ if (defined $prefix) {
+ if ($this_as =~ m/^\Q${prefix}.\E(.+)$/) {
+ my $remain = $1;
+ $remain =~ /^(?:(.*)\.)?([^.]+)$/;
+ $const{$1||''}{$2} = $val;
+ }
+ } else {
+ $this_as =~ /^(?:(.*)\.)?([^.]+)$/;
+ $const{$1||''}{$2} = $val;
+ }
+ }
-=item page
+ my $alias = $self->{attrs}{alias};
+ my $info = [ {}, {} ];
+ foreach my $key (keys %const) {
+ if (length $key && $key ne $alias) {
+ my $target = $info;
+ my @parts = split(/\./, $key);
+ foreach my $p (@parts) {
+ $target = $target->[1]->{$p} ||= [];
+ }
+ $target->[0] = $const{$key};
+ } else {
+ $info->[0] = $const{$key};
+ }
+ }
+
+ my @collapse;
+ if (defined $prefix) {
+ @collapse = map {
+ m/^\Q${prefix}.\E(.+)$/ ? ($1) : ()
+ } keys %{$self->{_attrs}{collapse}}
+ } else {
+ @collapse = keys %{$self->{_attrs}{collapse}};
+ };
+
+ if (@collapse) {
+ my ($c) = sort { length $a <=> length $b } @collapse;
+ my $target = $info;
+ foreach my $p (split(/\./, $c)) {
+ $target = $target->[1]->{$p} ||= [];
+ }
+ my $c_prefix = (defined($prefix) ? "${prefix}.${c}" : $c);
+ my @co_key = @{$self->{_attrs}{collapse}{$c_prefix}};
+ my $tree = $self->_collapse_result($as, $row, $c_prefix);
+ my %co_check = map { ($_, $tree->[0]->{$_}); } @co_key;
+ my (@final, @raw);
+
+ while (
+ !(
+ grep {
+ !defined($tree->[0]->{$_}) || $co_check{$_} ne $tree->[0]->{$_}
+ } @co_key
+ )
+ ) {
+ push(@final, $tree);
+ last unless (@raw = $self->cursor->next);
+ $row = $self->{stashed_row} = \@raw;
+ $tree = $self->_collapse_result($as, $row, $c_prefix);
+ }
+ @$target = (@final ? @final : [ {}, {} ]);
+ # single empty result to indicate an empty prefetched has_many
+ }
-Should the resultset be paged? This can also be enabled by using the
-'page' option.
+ #print "final info: " . Dumper($info);
+ return $info;
+}
-=item rows
+=head2 result_source
-For paged resultsset, how many rows per page
+=over 4
-=item offset
+=item Arguments: $result_source?
-For paged resultsset, which page to start on.
+=item Return Value: $result_source
=back
+An accessor for the primary ResultSource object from which this ResultSet
+is derived.
+
+=head2 result_class
+
+=over 4
+
+=item Arguments: $result_class?
+
+=item Return Value: $result_class
+
+=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
+L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
+
+=cut
+
+
+=head2 count
+
+=over 4
+
+=item Arguments: $cond, \%attrs??
+
+=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.
+
+=cut
+
+sub count {
+ 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;
+
+ $count -= $self->{attrs}{offset} if $self->{attrs}{offset};
+ $count = $self->{attrs}{rows} if
+ $self->{attrs}{rows} and $self->{attrs}{rows} < $count;
+ return $count;
+}
+
+sub _count { # Separated out so pager can get the full count
+ my $self = shift;
+ my $select = { count => '*' };
+
+ 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;
+ }
+ }
+ }
+
+ $select = { count => { distinct => \@distinct } };
+ }
+
+ $attrs->{select} = $select;
+ $attrs->{as} = [qw/count/];
+
+ # 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/;
+
+ my $tmp_rs = (ref $self)->new($self->result_source, $attrs);
+ my ($count) = $tmp_rs->cursor->next;
+ return $count;
+}
+
+=head2 count_literal
+
+=over 4
+
+=item Arguments: $sql_fragment, @bind_values
+
+=item Return Value: $count
+
+=back
+
+Counts the results in a literal query. Equivalent to calling L</search_literal>
+with the passed arguments, then L</count>.
+
+=cut
+
+sub count_literal { shift->search_literal(@_)->count; }
+
+=head2 all
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: @objects
+
+=back
+
+Returns all elements in the resultset. Called implicitly if the resultset
+is returned in list context.
+
+=cut
+
+sub all {
+ my ($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;
+ }
+
+ $self->set_cache(\@obj) if $self->{attrs}{cache};
+ return @obj;
+}
+
+=head2 reset
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: $self
+
+=back
+
+Resets the resultset's cursor, so you can iterate through the elements again.
+
+=cut
+
+sub reset {
+ my ($self) = @_;
+ delete $self->{_attrs} if exists $self->{_attrs};
+ $self->{all_cache_position} = 0;
+ $self->cursor->reset;
+ return $self;
+}
+
+=head2 first
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: $object?
+
+=back
+
+Resets the resultset and returns an object for the first result (if the
+resultset returns anything).
+
+=cut
+
+sub first {
+ return $_[0]->reset->next;
+}
+
+# _cond_for_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}
+ ];
+ }
+ 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];
+
+ my $hash;
+ if (ref $entry eq 'HASH') {
+ $hash = $self->_cond_for_update_delete($entry);
+ }
+ else {
+ $entry =~ /([^.]+)$/;
+ $hash->{$1} = $cond[++$i];
+ }
+
+ push @{$cond->{-and}}, $hash;
+ }
+ }
+ else {
+ foreach my $key (keys %{$full_cond}) {
+ $key =~ /([^.]+)$/;
+ $cond->{$1} = $full_cond->{$key};
+ }
+ }
+ }
+ else {
+ $self->throw_exception(
+ "Can't update/delete on resultset with condition unless hash or array"
+ );
+ }
+
+ return $cond;
+}
+
+
+=head2 update
+
+=over 4
+
+=item Arguments: \%values
+
+=item Return Value: $storage_rv
+
+=back
+
+Sets the specified columns in the resultset to the supplied values in a
+single query. Return value will be true if the update succeeded or false
+if no records were updated; exact type of success value is storage-dependent.
+
+=cut
+
+sub update {
+ my ($self, $values) = @_;
+ $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->from, $values, $cond
+ );
+}
+
+=head2 update_all
+
+=over 4
+
+=item Arguments: \%values
+
+=item Return Value: 1
+
+=back
+
+Fetches all objects and updates them one at a time. Note that C<update_all>
+will run DBIC cascade triggers, while L</update> will not.
+
+=cut
+
+sub update_all {
+ my ($self, $values) = @_;
+ $self->throw_exception("Values for update must be a hash")
+ unless ref $values eq 'HASH';
+ foreach my $obj ($self->all) {
+ $obj->set_columns($values)->update;
+ }
+ return 1;
+}
+
+=head2 delete
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: 1
+
+=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>.
+
+=cut
+
+sub delete {
+ my ($self) = @_;
+
+ my $cond = $self->_cond_for_update_delete;
+
+ $self->result_source->storage->delete($self->result_source->from, $cond);
+ return 1;
+}
+
+=head2 delete_all
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: 1
+
+=back
+
+Fetches all objects and deletes them one at a time. Note that C<delete_all>
+will run DBIC cascade triggers, while L</delete> will not.
+
+=cut
+
+sub delete_all {
+ my ($self) = @_;
+ $_->delete for $self->all;
+ return 1;
+}
+
+=head2 pager
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: $pager
+
+=back
+
+Return Value a L<Data::Page> object for the current resultset. Only makes
+sense for queries with a C<page> attribute.
+
+=cut
+
+sub pager {
+ my ($self) = @_;
+ my $attrs = $self->{attrs};
+ $self->throw_exception("Can't create pager for non-paged rs")
+ unless $self->{attrs}{page};
+ $attrs->{rows} ||= 10;
+ return $self->{pager} ||= Data::Page->new(
+ $self->_count, $attrs->{rows}, $self->{attrs}{page});
+}
+
+=head2 page
+
+=over 4
+
+=item Arguments: $page_number
+
+=item Return Value: $rs
+
+=back
+
+Returns a resultset for the $page_number page of the resultset on which page
+is called, where each page contains a number of rows equal to the 'rows'
+attribute set on the resultset (10 by default).
+
+=cut
+
+sub page {
+ my ($self, $page) = @_;
+ return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
+}
+
+=head2 new_result
+
+=over 4
+
+=item Arguments: \%vals
+
+=item Return Value: $object
+
+=back
+
+Creates an object in the resultset's result class and returns it.
+
+=cut
+
+sub new_result {
+ my ($self, $values) = @_;
+ $self->throw_exception( "new_result needs a hash" )
+ unless (ref $values eq 'HASH');
+ $self->throw_exception(
+ "Can't abstract implicit construct, condition not a hash"
+ ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
+
+ my $alias = $self->{attrs}{alias};
+ my $collapsed_cond = $self->{cond} ? $self->_collapse_cond($self->{cond}) : {};
+ my %new = (
+ %{ $self->_remove_alias($values, $alias) },
+ %{ $self->_remove_alias($collapsed_cond, $alias) },
+ -result_source => $self->result_source,
+ );
+
+ my $obj = $self->result_class->new(\%new);
+ return $obj;
+}
+
+# _collapse_cond
+#
+# Recursively collapse the condition.
+
+sub _collapse_cond {
+ my ($self, $cond, $collapsed) = @_;
+
+ $collapsed ||= {};
+
+ 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 $collapsed;
+}
+
+# _remove_alias
+#
+# Remove the specified alias from the specified query hash. A copy is made so
+# the original query is not modified.
+
+sub _remove_alias {
+ my ($self, $query, $alias) = @_;
+
+ my %orig = %{ $query || {} };
+ my %unaliased;
+
+ foreach my $key (keys %orig) {
+ if ($key !~ /\./) {
+ $unaliased{$key} = $orig{$key};
+ next;
+ }
+ $unaliased{$1} = $orig{$key}
+ if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
+ }
+
+ return \%unaliased;
+}
+
+=head2 find_or_new
+
+=over 4
+
+=item Arguments: \%vals, \%attrs?
+
+=item Return Value: $object
+
+=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.
+
+If you want objects to be saved immediately, use L</find_or_create> instead.
+
+=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);
+}
+
+=head2 create
+
+=over 4
+
+=item Arguments: \%vals
+
+=item Return Value: $object
+
+=back
+
+Inserts a record into the resultset and returns the object representing it.
+
+Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
+
+=cut
+
+sub create {
+ my ($self, $attrs) = @_;
+ $self->throw_exception( "create needs a hashref" )
+ unless ref $attrs eq 'HASH';
+ return $self->new_result($attrs)->insert;
+}
+
+=head2 find_or_create
+
+=over 4
+
+=item Arguments: \%vals, \%attrs?
+
+=item Return Value: $object
+
+=back
+
+ $class->find_or_create({ key => $val, ... });
+
+Tries to find a record based on its primary key or unique constraint; if none
+is found, creates one and returns that instead.
+
+ my $cd = $schema->resultset('CD')->find_or_create({
+ cdid => 5,
+ artist => 'Massive Attack',
+ title => 'Mezzanine',
+ year => 2005,
+ });
+
+Also takes an optional C<key> attribute, to search by a specific key or unique
+constraint. For example:
+
+ my $cd = $schema->resultset('CD')->find_or_create(
+ {
+ artist => 'Massive Attack',
+ title => 'Mezzanine',
+ },
+ { key => 'cd_artist_title' }
+ );
+
+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>.
+
+=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);
+}
+
+=head2 update_or_create
+
+=over 4
+
+=item Arguments: \%col_values, { key => $unique_constraint }?
+
+=item Return Value: $object
+
+=back
+
+ $class->update_or_create({ col => $val, ... });
+
+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:
+
+ # In your application
+ my $cd = $schema->resultset('CD')->update_or_create(
+ {
+ artist => 'Massive Attack',
+ title => 'Mezzanine',
+ year => 1998,
+ },
+ { key => 'cd_artist_title' }
+ );
+
+If no C<key> is specified, it searches on all unique constraints defined on the
+source, including the primary key.
+
+If the C<key> is specified as C<primary>, it searches only on the primary key.
+
+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>.
+
+=cut
+
+sub update_or_create {
+ 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 $self->create($cond);
+}
+
+=head2 get_cache
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: \@cache_objects?
+
+=back
+
+Gets the contents of the cache for the resultset, if the cache is set.
+
+=cut
+
+sub get_cache {
+ shift->{all_cache};
+}
+
+=head2 set_cache
+
+=over 4
+
+=item Arguments: \@cache_objects
+
+=item Return Value: \@cache_objects
+
+=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
+than re-querying the database even if the cache attr is not set.
+
+=cut
+
+sub set_cache {
+ my ( $self, $data ) = @_;
+ $self->throw_exception("set_cache requires an arrayref")
+ if defined($data) && (ref $data ne 'ARRAY');
+ $self->{all_cache} = $data;
+}
+
+=head2 clear_cache
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: []
+
+=back
+
+Clears the cache for the resultset.
+
+=cut
+
+sub clear_cache {
+ shift->set_cache(undef);
+}
+
+=head2 related_resultset
+
+=over 4
+
+=item Arguments: $relationship_name
+
+=item Return Value: $resultset
+
+=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 $rel_obj = $self->result_source->relationship_info($rel);
+
+ $self->throw_exception(
+ "search_related: result source '" . $self->result_source->name .
+ "' has no such relationship $rel")
+ unless $rel_obj;
+
+ my ($from,$seen) = $self->_resolve_from($rel);
+
+ my $join_count = $seen->{$rel};
+ my $alias = ($join_count > 1 ? join('_', $rel, $join_count) : $rel);
+
+ $self->result_source->schema->resultset($rel_obj->{class})->search_rs(
+ undef, {
+ %{$self->{attrs}||{}},
+ join => undef,
+ prefetch => undef,
+ select => undef,
+ as => undef,
+ alias => $alias,
+ where => $self->{cond},
+ seen_join => $seen,
+ from => $from,
+ });
+ };
+}
+
+sub _resolve_from {
+ my ($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 $join = ($attrs->{join}
+ ? [ $attrs->{join}, $extra_join ]
+ : $extra_join);
+ $from = [
+ @$from,
+ ($join ? $source->resolve_join($join, $attrs->{alias}, $seen) : ()),
+ ];
+
+ return ($from,$seen);
+}
+
+sub _resolved_attrs {
+ my $self = shift;
+ return $self->{_attrs} if $self->{_attrs};
+
+ 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);
+ }
+
+ $attrs->{from} ||= [ { 'me' => $source->from } ];
+
+ if (exists $attrs->{join} || exists $attrs->{prefetch}) {
+ my $join = delete $attrs->{join} || {};
+
+ if (defined $attrs->{prefetch}) {
+ $join = $self->_merge_attr(
+ $join, $attrs->{prefetch}
+ );
+ }
+
+ $attrs->{from} = # have to copy here to avoid corrupting the original
+ [
+ @{$attrs->{from}},
+ $source->resolve_join($join, $alias, { %{$attrs->{seen_join}||{}} })
+ ];
+ }
+
+ $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);
+ }
+ $attrs->{collapse} = $collapse;
+
+ return $self->{_attrs} = $attrs;
+}
+
+sub _merge_attr {
+ my ($self, $a, $b) = @_;
+ return $b unless defined($a);
+ return $a unless defined($b);
+
+ if (ref $b eq 'HASH' && ref $a eq 'HASH') {
+ foreach my $key (keys %{$b}) {
+ if (exists $a->{$key}) {
+ $a->{$key} = $self->_merge_attr($a->{$key}, $b->{$key});
+ } else {
+ $a->{$key} = $b->{$key};
+ }
+ }
+ return $a;
+ } else {
+ $a = [$a] unless ref $a eq 'ARRAY';
+ $b = [$b] unless ref $b eq 'ARRAY';
+
+ my $hash = {};
+ my @array;
+ foreach my $x ($a, $b) {
+ foreach my $element (@{$x}) {
+ if (ref $element eq 'HASH') {
+ $hash = $self->_merge_attr($hash, $element);
+ } elsif (ref $element eq 'ARRAY') {
+ push(@array, @{$element});
+ } else {
+ push(@array, $element) unless $b == $x
+ && grep { $_ eq $element } @array;
+ }
+ }
+ }
+
+ @array = grep { !exists $hash->{$_} } @array;
+
+ return keys %{$hash}
+ ? ( scalar(@array)
+ ? [$hash, @array]
+ : $hash
+ )
+ : \@array;
+ }
+}
+
+=head2 throw_exception
+
+See L<DBIx::Class::Schema/throw_exception> for details.
+
+=cut
+
+sub throw_exception {
+ my $self=shift;
+ $self->result_source->schema->throw_exception(@_);
+}
+
+# XXX: FIXME: Attributes docs need clearing up
+
+=head1 ATTRIBUTES
+
+The resultset takes various attributes that modify its behavior. Here's an
+overview of them:
+
+=head2 order_by
+
+=over 4
+
+=item Value: ($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'.
+
+Please note that if you have quoting enabled (see
+L<DBIx::Class::Storage/quote_char>) 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.)
+
+=head2 columns
+
+=over 4
+
+=item Value: \@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.)
+
+=head2 include_columns
+
+=over 4
+
+=item Value: \@columns
+
+=back
+
+Shortcut to include additional columns in the returned results - for example
+
+ $schema->resultset('CD')->search(undef, {
+ include_columns => ['artist.name'],
+ join => ['artist']
+ });
+
+would return all CDs and include a 'name' column to the information
+passed to object inflation
+
+=head2 select
+
+=over 4
+
+=item Value: \@select_columns
+
+=back
+
+Indicates which columns should be selected from the storage. You can use
+column names, or in the case of RDBMS back ends, function or stored procedure
+names:
+
+ $rs = $schema->resultset('Employee')->search(undef, {
+ select => [
+ 'name',
+ { count => 'employeeid' },
+ { sum => 'salary' }
+ ]
+ });
+
+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.
+
+=head2 +select
+
+=over 4
+
+Indicates additional columns to be selected from storage. Works the same as
+L<select> but adds columns to the selection.
+
+=back
+
+=head2 +as
+
+=over 4
+
+Indicates additional column names for those added via L<+select>.
+
+=back
+
+=head2 as
+
+=over 4
+
+=item Value: \@inflation_names
+
+=back
+
+Indicates column names for object inflation. This is used in conjunction with
+C<select>, usually when C<select> contains one or more function or stored
+procedure names:
+
+ $rs = $schema->resultset('Employee')->search(undef, {
+ select => [
+ 'name',
+ { count => 'employeeid' }
+ ],
+ as => ['name', 'employee_count'],
+ });
+
+ 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:
+
+ my $name = $employee->name();
+
+If on the other hand an accessor does not exist in the object, you need to
+use C<get_column> instead:
+
+ my $employee_count = $employee->get_column('employee_count');
+
+You can create your own accessors if required - see
+L<DBIx::Class::Manual::Cookbook> for details.
+
+Please note: This will NOT insert an C<AS employee_count> into the SQL
+statement produced, it is used for internal access only. Thus
+attempting to use the accessor in an C<order_by> clause or similar
+will fail miserably.
+
+To get around this limitation, you can supply literal SQL to your
+C<select> attibute that contains the C<AS alias> text, eg:
+
+ select => [\'myfield AS alias']
+
+=head2 join
+
+=over 4
+
+=item Value: ($rel_name | \@rel_names | \%rel_names)
+
+=back
+
+Contains a list of relationships that should be joined for this query. For
+example:
+
+ # Get CDs by Nine Inch Nails
+ my $rs = $schema->resultset('CD')->search(
+ { 'artist.name' => 'Nine Inch Nails' },
+ { join => 'artist' }
+ );
+
+Can also contain a hash reference to refer to the other relation's relations.
+For example:
+
+ package MyApp::Schema::Track;
+ use base qw/DBIx::Class/;
+ __PACKAGE__->table('track');
+ __PACKAGE__->add_columns(qw/trackid cd position title/);
+ __PACKAGE__->set_primary_key('trackid');
+ __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
+ 1;
+
+ # In your application
+ my $rs = $schema->resultset('Artist')->search(
+ { 'track.title' => 'Teardrop' },
+ {
+ join => { cd => 'track' },
+ order_by => 'artist.name',
+ }
+ );
+
+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
+ 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.
+
+ my $rs = $schema->resultset('Artist')->search({
+ 'cds.title' => 'Down to Earth',
+ 'cds_2.title' => 'Popular',
+ }, {
+ join => [ qw/cds cds/ ],
+ });
+
+will return a set of all artists that have both a cd with title 'Down
+to Earth' and a cd with title 'Popular'.
+
+If you want to fetch related objects from other tables as well, see C<prefetch>
+below.
+
+=head2 prefetch
+
+=over 4
+
+=item Value: ($rel_name | \@rel_names | \%rel_names)
+
+=back
+
+Contains one or more relationships that should be fetched along with the main
+query (when they are accessed afterwards they will have already been
+"prefetched"). 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'
+ }
+ }
+ );
+
+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. If you're prefetching to
+depth (e.g. { cd => { artist => 'label' } or similar), you'll need to
+specify the join as well.
+
+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').
+
+=head2 page
+
+=over 4
+
+=item Value: $page
+
+=back
+
+Makes the resultset paged and specifies the page to retrieve. Effectively
+identical to creating a non-pages resultset and then calling ->page($page)
+on it.
+
+If L<rows> attribute is not specified it defualts to 10 rows per page.
+
+=head2 rows
+
+=over 4
+
+=item Value: $rows
+
+=back
+
+Specifes 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
+
+=over 4
+
+=item Value: $offset
+
+=back
+
+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 group_by
+
+=over 4
+
+=item Value: \@columns
+
+=back
+
+A arrayref of columns to group by. Can include columns of joined tables.
+
+ group_by => [qw/ column1 column2 ... /]
+
+=head2 having
+
+=over 4
+
+=item Value: $condition
+
+=back
+
+HAVING is a select statement attribute that is applied between GROUP BY and
+ORDER BY. It is applied to the after the grouping calculations have been
+done.
+
+ having => { 'count(employee)' => { '>=', 100 } }
+
+=head2 distinct
+
+=over 4
+
+=item Value: (0 | 1)
+
+=back
+
+Set to 1 to group by all columns.
+
+=head2 where
+
+=over 4
+
+Adds to the WHERE clause.
+
+ # only return rows WHERE deleted IS NULL for all searches
+ __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
+
+Can be overridden by passing C<{ where => undef }> as an attribute
+to a resulset.
+
+=back
+
+=head2 cache
+
+Set to 1 to cache search results. This prevents extra SQL queries if you
+revisit rows in your ResultSet:
+
+ my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
+
+ while( my $artist = $resultset->next ) {
+ ... do stuff ...
+ }
+
+ $rs->first; # without cache, this would issue a query
+
+By default, searches are not cached.
+
+For more examples of using these attributes, see
+L<DBIx::Class::Manual::Cookbook>.
+
+=head2 from
+
+=over 4
+
+=item Value: \@from_clause
+
+=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.
+
+NOTE: Use this on your own risk. This allows you to shoot off your foot!
+
+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.
+
+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.
+
+The syntax is as follows -
+
+ [
+ { <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' }
+ ],
+ ]
+ },
+ );
+
+ # 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' }
+ ],
+ ]
+ },
+ );
+
+ # Equivalent SQL:
+ # SELECT child.* FROM person child
+ # INNER JOIN person father ON child.father_id = father.id
+
+=cut
+
1;
projects / dbsrgits/DBIx-Class.git / blobdiff