1 package DBIx::Class::ResultSet;
9 use Carp::Clan qw/^DBIx::Class/;
12 use DBIx::Class::ResultSetColumn;
13 use base qw/DBIx::Class/;
14 __PACKAGE__->load_components(qw/AccessorGroup/);
15 __PACKAGE__->mk_group_accessors('simple' => qw/result_source result_class/);
19 DBIx::Class::ResultSet - Responsible for fetching and creating resultset.
23 my $rs = $schema->resultset('User')->search(registered => 1);
24 my @rows = $schema->resultset('CD')->search(year => 2005);
28 The resultset is also known as an iterator. It is responsible for handling
29 queries that may return an arbitrary number of rows, e.g. via L</search>
30 or a C<has_many> relationship.
32 In the examples below, the following table classes are used:
34 package MyApp::Schema::Artist;
35 use base qw/DBIx::Class/;
36 __PACKAGE__->load_components(qw/Core/);
37 __PACKAGE__->table('artist');
38 __PACKAGE__->add_columns(qw/artistid name/);
39 __PACKAGE__->set_primary_key('artistid');
40 __PACKAGE__->has_many(cds => 'MyApp::Schema::CD');
43 package MyApp::Schema::CD;
44 use base qw/DBIx::Class/;
45 __PACKAGE__->load_components(qw/Core/);
46 __PACKAGE__->table('cd');
47 __PACKAGE__->add_columns(qw/cdid artist title year/);
48 __PACKAGE__->set_primary_key('cdid');
49 __PACKAGE__->belongs_to(artist => 'MyApp::Schema::Artist');
58 =item Arguments: $source, \%$attrs
60 =item Return Value: $rs
64 The resultset constructor. Takes a source object (usually a
65 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
66 L</ATTRIBUTES> below). Does not perform any queries -- these are
67 executed as needed by the other methods.
69 Generally you won't need to construct a resultset manually. You'll
70 automatically get one from e.g. a L</search> called in scalar context:
72 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
74 IMPORTANT: If called on an object, proxies to new_result instead so
76 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
78 will return a CD object, not a ResultSet.
84 return $class->new_result(@_) if ref $class;
86 my ($source, $attrs) = @_;
90 $attrs->{rows} ||= 10;
91 $attrs->{offset} ||= 0;
92 $attrs->{offset} += ($attrs->{rows} * ($attrs->{page} - 1));
95 $attrs->{alias} ||= 'me';
96 $attrs->{_orig_alias} ||= $attrs->{alias};
99 result_source => $source,
100 result_class => $attrs->{result_class} || $source->result_class,
101 cond => $attrs->{where},
102 # from => $attrs->{from},
103 # collapse => $collapse,
114 =item Arguments: $cond, \%attrs?
116 =item Return Value: $resultset (scalar context), @row_objs (list context)
120 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
121 my $new_rs = $cd_rs->search({ year => 2005 });
123 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
124 # year = 2005 OR year = 2004
126 If you need to pass in additional attributes but no additional condition,
127 call it as C<search(undef, \%attrs)>.
129 # "SELECT name, artistid FROM $artist_table"
130 my @all_artists = $schema->resultset('Artist')->search(undef, {
131 columns => [qw/name artistid/],
138 my $rs = $self->search_rs( @_ );
139 return (wantarray ? $rs->all : $rs);
146 =item Arguments: $cond, \%attrs?
148 =item Return Value: $resultset
152 This method does the same exact thing as search() except it will
153 always return a resultset, even in list context.
161 $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
162 my $our_attrs = exists $attrs->{_parent_attrs}
163 ? { %{delete $attrs->{_parent_attrs}} }
164 : { %{$self->{attrs}} };
165 my $having = delete $our_attrs->{having};
167 # XXX should only maintain _live_join_stack and generate _live_join_h from that
168 if ($attrs->{_live_join_stack}) {
169 foreach my $join (reverse @{$attrs->{_live_join_stack}}) {
170 $attrs->{_live_join_h} = defined $attrs->{_live_join_h}
171 ? { $join => $attrs->{_live_join_h} }
176 # merge new attrs into inherited
177 foreach my $key (qw/join prefetch/) {
178 next unless exists $attrs->{$key};
179 if (my $live_join = $attrs->{_live_join_stack} || $our_attrs->{_live_join_stack}) {
180 foreach my $join (reverse @{$live_join}) {
181 $attrs->{$key} = { $join => $attrs->{$key} };
185 $our_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, delete $attrs->{$key});
188 $our_attrs->{join} = $self->_merge_attr(
189 $our_attrs->{join}, $attrs->{_live_join_h}
190 ) if ($attrs->{_live_join_h});
192 if (defined $our_attrs->{prefetch}) {
193 $our_attrs->{join} = $self->_merge_attr(
194 $our_attrs->{join}, $our_attrs->{prefetch}
198 my $new_attrs = { %{$our_attrs}, %{$attrs} };
201 (@_ == 1 || ref $_[0] eq "HASH")
205 ? $self->throw_exception("Odd number of arguments to search")
212 if (defined $where) {
213 $new_attrs->{where} = (
214 defined $new_attrs->{where}
217 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
218 } $where, $new_attrs->{where}
224 if (defined $having) {
225 $new_attrs->{having} = (
226 defined $new_attrs->{having}
229 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
230 } $having, $new_attrs->{having}
236 my $rs = (ref $self)->new($self->result_source, $new_attrs);
237 $rs->{_parent_source} = $self->{_parent_source} if $self->{_parent_source};
239 unless (@_) { # no search, effectively just a clone
240 my $rows = $self->get_cache;
242 $rs->set_cache($rows);
248 =head2 search_literal
252 =item Arguments: $sql_fragment, @bind_values
254 =item Return Value: $resultset (scalar context), @row_objs (list context)
258 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
259 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
261 Pass a literal chunk of SQL to be added to the conditional part of the
267 my ($self, $cond, @vals) = @_;
268 my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {});
269 $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ];
270 return $self->search(\$cond, $attrs);
277 =item Arguments: @values | \%cols, \%attrs?
279 =item Return Value: $row_object
283 Finds a row based on its primary key or unique constraint. For example, to find
284 a row by its primary key:
286 my $cd = $schema->resultset('CD')->find(5);
288 You can also find a row by a specific unique constraint using the C<key>
289 attribute. For example:
291 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
292 key => 'cd_artist_title'
295 Additionally, you can specify the columns explicitly by name:
297 my $cd = $schema->resultset('CD')->find(
299 artist => 'Massive Attack',
300 title => 'Mezzanine',
302 { key => 'cd_artist_title' }
305 If the C<key> is specified as C<primary>, it searches only on the primary key.
307 If no C<key> is specified, it searches on all unique constraints defined on the
308 source, including the primary key.
310 See also L</find_or_create> and L</update_or_create>. For information on how to
311 declare unique constraints, see
312 L<DBIx::Class::ResultSource/add_unique_constraint>.
318 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
320 # Default to the primary key, but allow a specific key
321 my @cols = exists $attrs->{key}
322 ? $self->result_source->unique_constraint_columns($attrs->{key})
323 : $self->result_source->primary_columns;
324 $self->throw_exception(
325 "Can't find unless a primary key or unique constraint is defined"
328 # Parse out a hashref from input
330 if (ref $_[0] eq 'HASH') {
331 $input_query = { %{$_[0]} };
333 elsif (@_ == @cols) {
335 @{$input_query}{@cols} = @_;
338 # Compatibility: Allow e.g. find(id => $value)
339 carp "Find by key => value deprecated; please use a hashref instead";
343 my @unique_queries = $self->_unique_queries($input_query, $attrs);
345 # Handle cases where the ResultSet defines the query, or where the user is
347 my $query = @unique_queries ? \@unique_queries : $input_query;
351 my $rs = $self->search($query, $attrs);
352 return keys %{$rs->_resolved_attrs->{collapse}} ? $rs->next : $rs->single;
355 return keys %{$self->_resolved_attrs->{collapse}}
356 ? $self->search($query)->next
357 : $self->single($query);
363 # Build a list of queries which satisfy unique constraints.
365 sub _unique_queries {
366 my ($self, $query, $attrs) = @_;
368 my @constraint_names = exists $attrs->{key}
370 : $self->result_source->unique_constraint_names;
373 foreach my $name (@constraint_names) {
374 my @unique_cols = $self->result_source->unique_constraint_columns($name);
375 my $unique_query = $self->_build_unique_query($query, \@unique_cols);
377 next unless scalar keys %$unique_query;
379 # Add the ResultSet's alias
380 my $alias = $self->{attrs}{alias};
381 foreach my $key (grep { ! m/\./ } keys %$unique_query) {
382 $unique_query->{"$alias.$key"} = delete $unique_query->{$key};
385 push @unique_queries, $unique_query;
388 return @unique_queries;
391 # _build_unique_query
393 # Constrain the specified query hash based on the specified column names.
395 sub _build_unique_query {
396 my ($self, $query, $unique_cols) = @_;
399 map { $_ => $query->{$_} }
400 grep { exists $query->{$_} }
405 =head2 search_related
409 =item Arguments: $rel, $cond, \%attrs?
411 =item Return Value: $new_resultset
415 $new_rs = $cd_rs->search_related('artist', {
419 Searches the specified relationship, optionally specifying a condition and
420 attributes for matching records. See L</ATTRIBUTES> for more information.
425 return shift->related_resultset(shift)->search(@_);
432 =item Arguments: none
434 =item Return Value: $cursor
438 Returns a storage-driven cursor to the given resultset. See
439 L<DBIx::Class::Cursor> for more information.
446 my $attrs = { %{$self->_resolved_attrs} };
447 return $self->{cursor}
448 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
449 $attrs->{where},$attrs);
456 =item Arguments: $cond?
458 =item Return Value: $row_object?
462 my $cd = $schema->resultset('CD')->single({ year => 2001 });
464 Inflates the first result without creating a cursor if the resultset has
465 any records in it; if not returns nothing. Used by L</find> as an optimisation.
467 Can optionally take an additional condition *only* - this is a fast-code-path
468 method; if you need to add extra joins or similar call ->search and then
469 ->single without a condition on the $rs returned from that.
474 my ($self, $where) = @_;
475 my $attrs = { %{$self->_resolved_attrs} };
477 if (defined $attrs->{where}) {
480 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
481 $where, delete $attrs->{where} ]
484 $attrs->{where} = $where;
488 unless ($self->_is_unique_query($attrs->{where})) {
489 carp "Query not guaranteed to return a single row"
490 . "; please declare your unique constraints or use search instead";
493 my @data = $self->result_source->storage->select_single(
494 $attrs->{from}, $attrs->{select},
495 $attrs->{where}, $attrs
498 return (@data ? $self->_construct_object(@data) : ());
503 # Try to determine if the specified query is guaranteed to be unique, based on
504 # the declared unique constraints.
506 sub _is_unique_query {
507 my ($self, $query) = @_;
509 my $collapsed = $self->_collapse_query($query);
510 my $alias = $self->{attrs}{alias};
512 foreach my $name ($self->result_source->unique_constraint_names) {
513 my @unique_cols = map {
515 } $self->result_source->unique_constraint_columns($name);
517 # Count the values for each unique column
518 my %seen = map { $_ => 0 } @unique_cols;
520 foreach my $key (keys %$collapsed) {
521 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
522 next unless exists $seen{$aliased}; # Additional constraints are okay
523 $seen{$aliased} = scalar @{ $collapsed->{$key} };
526 # If we get 0 or more than 1 value for a column, it's not necessarily unique
527 return 1 unless grep { $_ != 1 } values %seen;
535 # Recursively collapse the query, accumulating values for each column.
537 sub _collapse_query {
538 my ($self, $query, $collapsed) = @_;
542 if (ref $query eq 'ARRAY') {
543 foreach my $subquery (@$query) {
544 next unless ref $subquery; # -or
545 # warn "ARRAY: " . Dumper $subquery;
546 $collapsed = $self->_collapse_query($subquery, $collapsed);
549 elsif (ref $query eq 'HASH') {
550 if (keys %$query and (keys %$query)[0] eq '-and') {
551 foreach my $subquery (@{$query->{-and}}) {
552 # warn "HASH: " . Dumper $subquery;
553 $collapsed = $self->_collapse_query($subquery, $collapsed);
557 # warn "LEAF: " . Dumper $query;
558 foreach my $key (keys %$query) {
559 push @{$collapsed->{$key}}, $query->{$key};
571 =item Arguments: $cond?
573 =item Return Value: $resultsetcolumn
577 my $max_length = $rs->get_column('length')->max;
579 Returns a ResultSetColumn instance for $column based on $self
584 my ($self, $column) = @_;
585 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
593 =item Arguments: $cond, \%attrs?
595 =item Return Value: $resultset (scalar context), @row_objs (list context)
599 # WHERE title LIKE '%blue%'
600 $cd_rs = $rs->search_like({ title => '%blue%'});
602 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
603 that this is simply a convenience method. You most likely want to use
604 L</search> with specific operators.
606 For more information, see L<DBIx::Class::Manual::Cookbook>.
612 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
613 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
614 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
615 return $class->search($query, { %$attrs });
622 =item Arguments: $first, $last
624 =item Return Value: $resultset (scalar context), @row_objs (list context)
628 Returns a resultset or object list representing a subset of elements from the
629 resultset slice is called on. Indexes are from 0, i.e., to get the first
632 my ($one, $two, $three) = $rs->slice(0, 2);
637 my ($self, $min, $max) = @_;
638 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
639 $attrs->{offset} = $self->{attrs}{offset} || 0;
640 $attrs->{offset} += $min;
641 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
642 return $self->search(undef(), $attrs);
643 #my $slice = (ref $self)->new($self->result_source, $attrs);
644 #return (wantarray ? $slice->all : $slice);
651 =item Arguments: none
653 =item Return Value: $result?
657 Returns the next element in the resultset (C<undef> is there is none).
659 Can be used to efficiently iterate over records in the resultset:
661 my $rs = $schema->resultset('CD')->search;
662 while (my $cd = $rs->next) {
666 Note that you need to store the resultset object, and call C<next> on it.
667 Calling C<< resultset('Table')->next >> repeatedly will always return the
668 first record from the resultset.
674 if (my $cache = $self->get_cache) {
675 $self->{all_cache_position} ||= 0;
676 return $cache->[$self->{all_cache_position}++];
678 if ($self->{attrs}{cache}) {
679 $self->{all_cache_position} = 1;
680 return ($self->all)[0];
683 exists $self->{stashed_row}
684 ? @{delete $self->{stashed_row}}
685 : $self->cursor->next
687 return unless (@row);
688 return $self->_construct_object(@row);
691 sub _resolved_attrs {
693 return $self->{_attrs} if $self->{_attrs};
695 my $attrs = $self->{attrs};
696 my $source = $self->{_parent_source} || $self->{result_source};
697 my $alias = $attrs->{_orig_alias};
699 # XXX - lose storable dclone
700 my $record_filter = delete $attrs->{record_filter};
701 $attrs = Storable::dclone($attrs || {}); # { %{ $attrs || {} } };
702 $attrs->{record_filter} = $record_filter if $record_filter;
704 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
705 if ($attrs->{columns}) {
707 } elsif (!$attrs->{select}) {
708 $attrs->{columns} = [ $self->{result_source}->columns ];
711 my $select_alias = $self->{attrs}{alias};
712 $attrs->{select} ||= [
713 map { m/\./ ? $_ : "${select_alias}.$_" } @{delete $attrs->{columns}}
716 map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{$attrs->{select}}
720 if ($adds = delete $attrs->{include_columns}) {
721 $adds = [$adds] unless ref $adds eq 'ARRAY';
722 push(@{$attrs->{select}}, @$adds);
723 push(@{$attrs->{as}}, map { m/([^.]+)$/; $1 } @$adds);
725 if ($adds = delete $attrs->{'+select'}) {
726 $adds = [$adds] unless ref $adds eq 'ARRAY';
727 push(@{$attrs->{select}}, map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds);
729 if (my $adds = delete $attrs->{'+as'}) {
730 $adds = [$adds] unless ref $adds eq 'ARRAY';
731 push(@{$attrs->{as}}, @$adds);
734 $attrs->{from} ||= [ { $alias => $source->from } ];
735 $attrs->{seen_join} ||= {};
737 if (my $join = delete $attrs->{join}) {
738 foreach my $j (ref $join eq 'ARRAY' ? @$join : ($join)) {
739 if (ref $j eq 'HASH') {
740 $seen{$_} = 1 foreach keys %$j;
745 push(@{$attrs->{from}},
746 $source->resolve_join($join, $alias, $attrs->{seen_join})
750 $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct};
751 if ($attrs->{order_by}) {
752 $attrs->{order_by} = [ $attrs->{order_by} ] unless ref $attrs->{order_by};
754 $attrs->{order_by} ||= [];
757 my $collapse = $attrs->{collapse} || {};
758 if (my $prefetch = delete $attrs->{prefetch}) {
760 foreach my $p (ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch)) {
761 if ( ref $p eq 'HASH' ) {
762 foreach my $key (keys %$p) {
763 push(@{$attrs->{from}}, $source->resolve_join($p, $alias))
767 push(@{$attrs->{from}}, $source->resolve_join($p, $alias))
770 # bring joins back to level of current class
771 $p = $self->_reduce_joins($p, $attrs) if $attrs->{_live_join_stack};
773 my @prefetch = $self->result_source->resolve_prefetch(
774 $p, $alias, {}, \@pre_order, $collapse
776 push(@{$attrs->{select}}, map { $_->[0] } @prefetch);
777 push(@{$attrs->{as}}, map { $_->[1] } @prefetch);
780 push(@{$attrs->{order_by}}, @pre_order);
782 $attrs->{collapse} = $collapse;
784 return $self->{_attrs} = $attrs;
788 my ($self, $a, $b) = @_;
791 if (ref $b eq 'HASH' && ref $a eq 'HASH') {
792 foreach my $key (keys %{$b}) {
793 if (exists $a->{$key}) {
794 $a->{$key} = $self->_merge_attr($a->{$key}, $b->{$key});
796 $a->{$key} = $b->{$key};
801 $a = [$a] unless ref $a eq 'ARRAY';
802 $b = [$b] unless ref $b eq 'ARRAY';
806 foreach my $x ($a, $b) {
807 foreach my $element (@{$x}) {
808 if (ref $element eq 'HASH') {
809 $hash = $self->_merge_attr($hash, $element);
810 } elsif (ref $element eq 'ARRAY') {
811 push(@array, @{$element});
813 push(@array, $element) unless $b == $x
814 && grep { $_ eq $element } @array;
819 @array = grep { !exists $hash->{$_} } @array;
830 # bring the joins (which are from the original class) to the level
831 # of the current class so that we can resolve them properly
833 my ($self, $p, $attrs) = @_;
836 foreach my $join (@{$attrs->{_live_join_stack}}) {
837 if (ref $p eq 'HASH') {
838 return undef unless exists $p->{$join};
840 } elsif (ref $p eq 'ARRAY') {
841 foreach my $pe (@{$p}) {
842 return undef if $pe eq $join;
843 if (ref $pe eq 'HASH' && exists $pe->{$join}) {
856 sub _construct_object {
857 my ($self, @row) = @_;
858 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row);
859 my $new = $self->result_class->inflate_result($self->result_source, @$info);
860 $new = $self->{_attrs}{record_filter}->($new)
861 if exists $self->{_attrs}{record_filter};
865 sub _collapse_result {
866 my ($self, $as, $row, $prefix) = @_;
871 foreach my $this_as (@$as) {
872 my $val = shift @copy;
873 if (defined $prefix) {
874 if ($this_as =~ m/^\Q${prefix}.\E(.+)$/) {
876 $remain =~ /^(?:(.*)\.)?([^.]+)$/;
877 $const{$1||''}{$2} = $val;
880 $this_as =~ /^(?:(.*)\.)?([^.]+)$/;
881 $const{$1||''}{$2} = $val;
885 my $alias = $self->{attrs}{alias};
886 my $info = [ {}, {} ];
887 foreach my $key (keys %const) {
888 if (length $key && $key ne $alias) {
890 my @parts = split(/\./, $key);
891 foreach my $p (@parts) {
892 $target = $target->[1]->{$p} ||= [];
894 $target->[0] = $const{$key};
896 $info->[0] = $const{$key};
901 if (defined $prefix) {
903 m/^\Q${prefix}.\E(.+)$/ ? ($1) : ()
904 } keys %{$self->{_attrs}{collapse}}
906 @collapse = keys %{$self->{_attrs}{collapse}};
910 my ($c) = sort { length $a <=> length $b } @collapse;
912 foreach my $p (split(/\./, $c)) {
913 $target = $target->[1]->{$p} ||= [];
915 my $c_prefix = (defined($prefix) ? "${prefix}.${c}" : $c);
916 my @co_key = @{$self->{_attrs}{collapse}{$c_prefix}};
917 my $tree = $self->_collapse_result($as, $row, $c_prefix);
918 my %co_check = map { ($_, $tree->[0]->{$_}); } @co_key;
924 !defined($tree->[0]->{$_}) || $co_check{$_} ne $tree->[0]->{$_}
929 last unless (@raw = $self->cursor->next);
930 $row = $self->{stashed_row} = \@raw;
931 $tree = $self->_collapse_result($as, $row, $c_prefix);
933 @$target = (@final ? @final : [ {}, {} ]);
934 # single empty result to indicate an empty prefetched has_many
937 #print "final info: " . Dumper($info);
945 =item Arguments: $result_source?
947 =item Return Value: $result_source
951 An accessor for the primary ResultSource object from which this ResultSet
961 =item Arguments: $cond, \%attrs??
963 =item Return Value: $count
967 Performs an SQL C<COUNT> with the same query as the resultset was built
968 with to find the number of elements. If passed arguments, does a search
969 on the resultset and counts the results of that.
971 Note: When using C<count> with C<group_by>, L<DBIX::Class> emulates C<GROUP BY>
972 using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do
973 not support C<DISTINCT> with multiple columns. If you are using such a
974 database, you should only use columns from the main table in your C<group_by>
981 return $self->search(@_)->count if @_ and defined $_[0];
982 return scalar @{ $self->get_cache } if $self->get_cache;
983 my $count = $self->_count;
984 return 0 unless $count;
986 $count -= $self->{attrs}{offset} if $self->{attrs}{offset};
987 $count = $self->{attrs}{rows} if
988 $self->{attrs}{rows} and $self->{attrs}{rows} < $count;
992 sub _count { # Separated out so pager can get the full count
994 my $select = { count => '*' };
996 my $attrs = { %{$self->_resolved_attrs} };
997 if (my $group_by = delete $attrs->{group_by}) {
998 delete $attrs->{having};
999 my @distinct = (ref $group_by ? @$group_by : ($group_by));
1000 # todo: try CONCAT for multi-column pk
1001 my @pk = $self->result_source->primary_columns;
1003 my $alias = $attrs->{_orig_alias};
1004 foreach my $column (@distinct) {
1005 if ($column =~ qr/^(?:\Q${alias}.\E)?$pk[0]$/) {
1006 @distinct = ($column);
1012 $select = { count => { distinct => \@distinct } };
1015 $attrs->{select} = $select;
1016 $attrs->{as} = [qw/count/];
1018 # offset, order by and page are not needed to count. record_filter is cdbi
1019 delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/;
1020 my $tmp_rs = (ref $self)->new($self->result_source, $attrs);
1021 $tmp_rs->{_parent_source} = $self->{_parent_source} if $self->{_parent_source};
1022 #XXX - hack to pass through parent of related resultsets
1024 my ($count) = $tmp_rs->cursor->next;
1028 =head2 count_literal
1032 =item Arguments: $sql_fragment, @bind_values
1034 =item Return Value: $count
1038 Counts the results in a literal query. Equivalent to calling L</search_literal>
1039 with the passed arguments, then L</count>.
1043 sub count_literal { shift->search_literal(@_)->count; }
1049 =item Arguments: none
1051 =item Return Value: @objects
1055 Returns all elements in the resultset. Called implicitly if the resultset
1056 is returned in list context.
1062 return @{ $self->get_cache } if $self->get_cache;
1066 # TODO: don't call resolve here
1067 if (keys %{$self->_resolved_attrs->{collapse}}) {
1068 # if ($self->{attrs}{prefetch}) {
1069 # Using $self->cursor->all is really just an optimisation.
1070 # If we're collapsing has_many prefetches it probably makes
1071 # very little difference, and this is cleaner than hacking
1072 # _construct_object to survive the approach
1073 my @row = $self->cursor->next;
1075 push(@obj, $self->_construct_object(@row));
1076 @row = (exists $self->{stashed_row}
1077 ? @{delete $self->{stashed_row}}
1078 : $self->cursor->next);
1081 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1084 $self->set_cache(\@obj) if $self->{attrs}{cache};
1092 =item Arguments: none
1094 =item Return Value: $self
1098 Resets the resultset's cursor, so you can iterate through the elements again.
1104 delete $self->{_attrs} if exists $self->{_attrs};
1105 $self->{all_cache_position} = 0;
1106 $self->cursor->reset;
1114 =item Arguments: none
1116 =item Return Value: $object?
1120 Resets the resultset and returns an object for the first result (if the
1121 resultset returns anything).
1126 return $_[0]->reset->next;
1129 # _cond_for_update_delete
1131 # update/delete require the condition to be modified to handle
1132 # the differing SQL syntax available. This transforms the $self->{cond}
1133 # appropriately, returning the new condition.
1135 sub _cond_for_update_delete {
1139 # No-op. No condition, we're updating/deleting everything
1140 return $cond unless ref $self->{cond};
1142 if (ref $self->{cond} eq 'ARRAY') {
1146 foreach my $key (keys %{$_}) {
1148 $hash{$1} = $_->{$key};
1154 elsif (ref $self->{cond} eq 'HASH') {
1155 if ((keys %{$self->{cond}})[0] eq '-and') {
1158 my @cond = @{$self->{cond}{-and}};
1159 for (my $i = 0; $i < @cond; $i++) {
1160 my $entry = $cond[$i];
1163 if (ref $entry eq 'HASH') {
1164 foreach my $key (keys %{$entry}) {
1166 $hash{$1} = $entry->{$key};
1170 $entry =~ /([^.]+)$/;
1171 $hash{$1} = $cond[++$i];
1174 push @{$cond->{-and}}, \%hash;
1178 foreach my $key (keys %{$self->{cond}}) {
1180 $cond->{$1} = $self->{cond}{$key};
1185 $self->throw_exception(
1186 "Can't update/delete on resultset with condition unless hash or array"
1198 =item Arguments: \%values
1200 =item Return Value: $storage_rv
1204 Sets the specified columns in the resultset to the supplied values in a
1205 single query. Return value will be true if the update succeeded or false
1206 if no records were updated; exact type of success value is storage-dependent.
1211 my ($self, $values) = @_;
1212 $self->throw_exception("Values for update must be a hash")
1213 unless ref $values eq 'HASH';
1215 my $cond = $self->_cond_for_update_delete;
1217 return $self->result_source->storage->update(
1218 $self->result_source->from, $values, $cond
1226 =item Arguments: \%values
1228 =item Return Value: 1
1232 Fetches all objects and updates them one at a time. Note that C<update_all>
1233 will run DBIC cascade triggers, while L</update> will not.
1238 my ($self, $values) = @_;
1239 $self->throw_exception("Values for update must be a hash")
1240 unless ref $values eq 'HASH';
1241 foreach my $obj ($self->all) {
1242 $obj->set_columns($values)->update;
1251 =item Arguments: none
1253 =item Return Value: 1
1257 Deletes the contents of the resultset from its result source. Note that this
1258 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1266 my $cond = $self->_cond_for_update_delete;
1268 $self->result_source->storage->delete($self->result_source->from, $cond);
1276 =item Arguments: none
1278 =item Return Value: 1
1282 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1283 will run DBIC cascade triggers, while L</delete> will not.
1289 $_->delete for $self->all;
1297 =item Arguments: none
1299 =item Return Value: $pager
1303 Return Value a L<Data::Page> object for the current resultset. Only makes
1304 sense for queries with a C<page> attribute.
1310 my $attrs = $self->{attrs};
1311 $self->throw_exception("Can't create pager for non-paged rs")
1312 unless $self->{attrs}{page};
1313 $attrs->{rows} ||= 10;
1314 return $self->{pager} ||= Data::Page->new(
1315 $self->_count, $attrs->{rows}, $self->{attrs}{page});
1322 =item Arguments: $page_number
1324 =item Return Value: $rs
1328 Returns a resultset for the $page_number page of the resultset on which page
1329 is called, where each page contains a number of rows equal to the 'rows'
1330 attribute set on the resultset (10 by default).
1335 my ($self, $page) = @_;
1336 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1343 =item Arguments: \%vals
1345 =item Return Value: $object
1349 Creates an object in the resultset's result class and returns it.
1354 my ($self, $values) = @_;
1355 $self->throw_exception( "new_result needs a hash" )
1356 unless (ref $values eq 'HASH');
1357 $self->throw_exception(
1358 "Can't abstract implicit construct, condition not a hash"
1359 ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
1361 my $alias = $self->{attrs}{_orig_alias};
1362 foreach my $key (keys %{$self->{cond}||{}}) {
1363 $new{$1} = $self->{cond}{$key} if ($key =~ m/^(?:\Q${alias}.\E)?([^.]+)$/);
1365 my $obj = $self->result_class->new(\%new);
1366 $obj->result_source($self->result_source) if $obj->can('result_source');
1374 =item Arguments: \%vals, \%attrs?
1376 =item Return Value: $object
1380 Find an existing record from this resultset. If none exists, instantiate a new
1381 result object and return it. The object will not be saved into your storage
1382 until you call L<DBIx::Class::Row/insert> on it.
1384 If you want objects to be saved immediately, use L</find_or_create> instead.
1390 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1391 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1392 my $exists = $self->find($hash, $attrs);
1393 return defined $exists ? $exists : $self->new_result($hash);
1400 =item Arguments: \%vals
1402 =item Return Value: $object
1406 Inserts a record into the resultset and returns the object representing it.
1408 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
1413 my ($self, $attrs) = @_;
1414 $self->throw_exception( "create needs a hashref" )
1415 unless ref $attrs eq 'HASH';
1416 return $self->new_result($attrs)->insert;
1419 =head2 find_or_create
1423 =item Arguments: \%vals, \%attrs?
1425 =item Return Value: $object
1429 $class->find_or_create({ key => $val, ... });
1431 Tries to find a record based on its primary key or unique constraint; if none
1432 is found, creates one and returns that instead.
1434 my $cd = $schema->resultset('CD')->find_or_create({
1436 artist => 'Massive Attack',
1437 title => 'Mezzanine',
1441 Also takes an optional C<key> attribute, to search by a specific key or unique
1442 constraint. For example:
1444 my $cd = $schema->resultset('CD')->find_or_create(
1446 artist => 'Massive Attack',
1447 title => 'Mezzanine',
1449 { key => 'cd_artist_title' }
1452 See also L</find> and L</update_or_create>. For information on how to declare
1453 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1457 sub find_or_create {
1459 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1460 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1461 my $exists = $self->find($hash, $attrs);
1462 return defined $exists ? $exists : $self->create($hash);
1465 =head2 update_or_create
1469 =item Arguments: \%col_values, { key => $unique_constraint }?
1471 =item Return Value: $object
1475 $class->update_or_create({ col => $val, ... });
1477 First, searches for an existing row matching one of the unique constraints
1478 (including the primary key) on the source of this resultset. If a row is
1479 found, updates it with the other given column values. Otherwise, creates a new
1482 Takes an optional C<key> attribute to search on a specific unique constraint.
1485 # In your application
1486 my $cd = $schema->resultset('CD')->update_or_create(
1488 artist => 'Massive Attack',
1489 title => 'Mezzanine',
1492 { key => 'cd_artist_title' }
1495 If no C<key> is specified, it searches on all unique constraints defined on the
1496 source, including the primary key.
1498 If the C<key> is specified as C<primary>, it searches only on the primary key.
1500 See also L</find> and L</find_or_create>. For information on how to declare
1501 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1505 sub update_or_create {
1507 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1508 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
1510 my $row = $self->find($cond);
1512 $row->update($cond);
1516 return $self->create($cond);
1523 =item Arguments: none
1525 =item Return Value: \@cache_objects?
1529 Gets the contents of the cache for the resultset, if the cache is set.
1541 =item Arguments: \@cache_objects
1543 =item Return Value: \@cache_objects
1547 Sets the contents of the cache for the resultset. Expects an arrayref
1548 of objects of the same class as those produced by the resultset. Note that
1549 if the cache is set the resultset will return the cached objects rather
1550 than re-querying the database even if the cache attr is not set.
1555 my ( $self, $data ) = @_;
1556 $self->throw_exception("set_cache requires an arrayref")
1557 if defined($data) && (ref $data ne 'ARRAY');
1558 $self->{all_cache} = $data;
1565 =item Arguments: none
1567 =item Return Value: []
1571 Clears the cache for the resultset.
1576 shift->set_cache(undef);
1579 =head2 related_resultset
1583 =item Arguments: $relationship_name
1585 =item Return Value: $resultset
1589 Returns a related resultset for the supplied relationship name.
1591 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
1595 sub related_resultset {
1596 my ($self, $rel) = @_;
1598 $self->{related_resultsets} ||= {};
1599 return $self->{related_resultsets}{$rel} ||= do {
1600 my $rel_obj = $self->result_source->relationship_info($rel);
1602 $self->throw_exception(
1603 "search_related: result source '" . $self->result_source->name .
1604 "' has no such relationship $rel")
1607 my @live_join_stack = @{$self->{attrs}{_live_join_stack}||[]};
1609 # XXX mst: I'm sure this is wrong, somehow
1610 # something with complex joins early on could die on search_rel
1611 # followed by a prefetch. I think. need a test case.
1613 my $join_count = scalar(grep { $_ eq $rel } @live_join_stack);
1614 my $alias = $join_count ? join('_', $rel, $join_count+1) : $rel;
1616 push(@live_join_stack, $rel);
1618 my $rs = $self->result_source->schema->resultset($rel_obj->{class})->search(
1623 _live_join_stack => \@live_join_stack,
1624 _parent_attrs => $self->{attrs}}
1627 # keep reference of the original resultset
1628 $rs->{_parent_source} = $self->{_parent_source} || $self->result_source;
1634 =head2 throw_exception
1636 See L<DBIx::Class::Schema/throw_exception> for details.
1640 sub throw_exception {
1642 $self->result_source->schema->throw_exception(@_);
1645 # XXX: FIXME: Attributes docs need clearing up
1649 The resultset takes various attributes that modify its behavior. Here's an
1656 =item Value: ($order_by | \@order_by)
1660 Which column(s) to order the results by. This is currently passed
1661 through directly to SQL, so you can give e.g. C<year DESC> for a
1662 descending order on the column `year'.
1664 Please note that if you have quoting enabled (see
1665 L<DBIx::Class::Storage/quote_char>) you will need to do C<\'year DESC' > to
1666 specify an order. (The scalar ref causes it to be passed as raw sql to the DB,
1667 so you will need to manually quote things as appropriate.)
1673 =item Value: \@columns
1677 Shortcut to request a particular set of columns to be retrieved. Adds
1678 C<me.> onto the start of any column without a C<.> in it and sets C<select>
1679 from that, then auto-populates C<as> from C<select> as normal. (You may also
1680 use the C<cols> attribute, as in earlier versions of DBIC.)
1682 =head2 include_columns
1686 =item Value: \@columns
1690 Shortcut to include additional columns in the returned results - for example
1692 $schema->resultset('CD')->search(undef, {
1693 include_columns => ['artist.name'],
1697 would return all CDs and include a 'name' column to the information
1698 passed to object inflation
1704 =item Value: \@select_columns
1708 Indicates which columns should be selected from the storage. You can use
1709 column names, or in the case of RDBMS back ends, function or stored procedure
1712 $rs = $schema->resultset('Employee')->search(undef, {
1715 { count => 'employeeid' },
1720 When you use function/stored procedure names and do not supply an C<as>
1721 attribute, the column names returned are storage-dependent. E.g. MySQL would
1722 return a column named C<count(employeeid)> in the above example.
1728 Indicates additional columns to be selected from storage. Works the same as
1729 L<select> but adds columns to the selection.
1737 Indicates additional column names for those added via L<+select>.
1745 =item Value: \@inflation_names
1749 Indicates column names for object inflation. This is used in conjunction with
1750 C<select>, usually when C<select> contains one or more function or stored
1753 $rs = $schema->resultset('Employee')->search(undef, {
1756 { count => 'employeeid' }
1758 as => ['name', 'employee_count'],
1761 my $employee = $rs->first(); # get the first Employee
1763 If the object against which the search is performed already has an accessor
1764 matching a column name specified in C<as>, the value can be retrieved using
1765 the accessor as normal:
1767 my $name = $employee->name();
1769 If on the other hand an accessor does not exist in the object, you need to
1770 use C<get_column> instead:
1772 my $employee_count = $employee->get_column('employee_count');
1774 You can create your own accessors if required - see
1775 L<DBIx::Class::Manual::Cookbook> for details.
1777 Please note: This will NOT insert an C<AS employee_count> into the SQL statement
1778 produced, it is used for internal access only. Thus attempting to use the accessor
1779 in an C<order_by> clause or similar will fail misrably.
1785 =item Value: ($rel_name | \@rel_names | \%rel_names)
1789 Contains a list of relationships that should be joined for this query. For
1792 # Get CDs by Nine Inch Nails
1793 my $rs = $schema->resultset('CD')->search(
1794 { 'artist.name' => 'Nine Inch Nails' },
1795 { join => 'artist' }
1798 Can also contain a hash reference to refer to the other relation's relations.
1801 package MyApp::Schema::Track;
1802 use base qw/DBIx::Class/;
1803 __PACKAGE__->table('track');
1804 __PACKAGE__->add_columns(qw/trackid cd position title/);
1805 __PACKAGE__->set_primary_key('trackid');
1806 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
1809 # In your application
1810 my $rs = $schema->resultset('Artist')->search(
1811 { 'track.title' => 'Teardrop' },
1813 join => { cd => 'track' },
1814 order_by => 'artist.name',
1818 If the same join is supplied twice, it will be aliased to <rel>_2 (and
1819 similarly for a third time). For e.g.
1821 my $rs = $schema->resultset('Artist')->search({
1822 'cds.title' => 'Down to Earth',
1823 'cds_2.title' => 'Popular',
1825 join => [ qw/cds cds/ ],
1828 will return a set of all artists that have both a cd with title 'Down
1829 to Earth' and a cd with title 'Popular'.
1831 If you want to fetch related objects from other tables as well, see C<prefetch>
1838 =item Value: ($rel_name | \@rel_names | \%rel_names)
1842 Contains one or more relationships that should be fetched along with the main
1843 query (when they are accessed afterwards they will have already been
1844 "prefetched"). This is useful for when you know you will need the related
1845 objects, because it saves at least one query:
1847 my $rs = $schema->resultset('Tag')->search(
1856 The initial search results in SQL like the following:
1858 SELECT tag.*, cd.*, artist.* FROM tag
1859 JOIN cd ON tag.cd = cd.cdid
1860 JOIN artist ON cd.artist = artist.artistid
1862 L<DBIx::Class> has no need to go back to the database when we access the
1863 C<cd> or C<artist> relationships, which saves us two SQL statements in this
1866 Simple prefetches will be joined automatically, so there is no need
1867 for a C<join> attribute in the above search. If you're prefetching to
1868 depth (e.g. { cd => { artist => 'label' } or similar), you'll need to
1869 specify the join as well.
1871 C<prefetch> can be used with the following relationship types: C<belongs_to>,
1872 C<has_one> (or if you're using C<add_relationship>, any relationship declared
1873 with an accessor type of 'single' or 'filter').
1883 Makes the resultset paged and specifies the page to retrieve. Effectively
1884 identical to creating a non-pages resultset and then calling ->page($page)
1887 If L<rows> attribute is not specified it defualts to 10 rows per page.
1897 Specifes the maximum number of rows for direct retrieval or the number of
1898 rows per page if the page attribute or method is used.
1904 =item Value: $offset
1908 Specifies the (zero-based) row number for the first row to be returned, or the
1909 of the first row of the first page if paging is used.
1915 =item Value: \@columns
1919 A arrayref of columns to group by. Can include columns of joined tables.
1921 group_by => [qw/ column1 column2 ... /]
1927 =item Value: $condition
1931 HAVING is a select statement attribute that is applied between GROUP BY and
1932 ORDER BY. It is applied to the after the grouping calculations have been
1935 having => { 'count(employee)' => { '>=', 100 } }
1941 =item Value: (0 | 1)
1945 Set to 1 to group by all columns.
1951 Adds to the WHERE clause.
1953 # only return rows WHERE deleted IS NULL for all searches
1954 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
1956 Can be overridden by passing C<{ where => undef }> as an attribute
1963 Set to 1 to cache search results. This prevents extra SQL queries if you
1964 revisit rows in your ResultSet:
1966 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
1968 while( my $artist = $resultset->next ) {
1972 $rs->first; # without cache, this would issue a query
1974 By default, searches are not cached.
1976 For more examples of using these attributes, see
1977 L<DBIx::Class::Manual::Cookbook>.
1983 =item Value: \@from_clause
1987 The C<from> attribute gives you manual control over the C<FROM> clause of SQL
1988 statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
1991 NOTE: Use this on your own risk. This allows you to shoot off your foot!
1993 C<join> will usually do what you need and it is strongly recommended that you
1994 avoid using C<from> unless you cannot achieve the desired result using C<join>.
1995 And we really do mean "cannot", not just tried and failed. Attempting to use
1996 this because you're having problems with C<join> is like trying to use x86
1997 ASM because you've got a syntax error in your C. Trust us on this.
1999 Now, if you're still really, really sure you need to use this (and if you're
2000 not 100% sure, ask the mailing list first), here's an explanation of how this
2003 The syntax is as follows -
2006 { <alias1> => <table1> },
2008 { <alias2> => <table2>, -join_type => 'inner|left|right' },
2009 [], # nested JOIN (optional)
2010 { <table1.column1> => <table2.column2>, ... (more conditions) },
2012 # More of the above [ ] may follow for additional joins
2019 ON <table1.column1> = <table2.column2>
2020 <more joins may follow>
2022 An easy way to follow the examples below is to remember the following:
2024 Anything inside "[]" is a JOIN
2025 Anything inside "{}" is a condition for the enclosing JOIN
2027 The following examples utilize a "person" table in a family tree application.
2028 In order to express parent->child relationships, this table is self-joined:
2030 # Person->belongs_to('father' => 'Person');
2031 # Person->belongs_to('mother' => 'Person');
2033 C<from> can be used to nest joins. Here we return all children with a father,
2034 then search against all mothers of those children:
2036 $rs = $schema->resultset('Person')->search(
2039 alias => 'mother', # alias columns in accordance with "from"
2041 { mother => 'person' },
2044 { child => 'person' },
2046 { father => 'person' },
2047 { 'father.person_id' => 'child.father_id' }
2050 { 'mother.person_id' => 'child.mother_id' }
2057 # SELECT mother.* FROM person mother
2060 # JOIN person father
2061 # ON ( father.person_id = child.father_id )
2063 # ON ( mother.person_id = child.mother_id )
2065 The type of any join can be controlled manually. To search against only people
2066 with a father in the person table, we could explicitly use C<INNER JOIN>:
2068 $rs = $schema->resultset('Person')->search(
2071 alias => 'child', # alias columns in accordance with "from"
2073 { child => 'person' },
2075 { father => 'person', -join_type => 'inner' },
2076 { 'father.id' => 'child.father_id' }
2083 # SELECT child.* FROM person child
2084 # INNER JOIN person father ON child.father_id = father.id