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.
162 unless (@_) { # no search, effectively just a clone
163 $rows = $self->get_cache;
167 $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
168 my $our_attrs = exists $attrs->{_parent_attrs}
169 ? { %{delete $attrs->{_parent_attrs}} }
170 : { %{$self->{attrs}} };
171 my $having = delete $our_attrs->{having};
173 # XXX should only maintain _live_join_stack and generate _live_join_h from that
174 if ($attrs->{_live_join_stack}) {
175 foreach my $join (reverse @{$attrs->{_live_join_stack}}) {
176 $attrs->{_live_join_h} = defined $attrs->{_live_join_h}
177 ? { $join => $attrs->{_live_join_h} }
182 # merge new attrs into inherited
183 foreach my $key (qw/join prefetch/) {
184 next unless exists $attrs->{$key};
185 if (my $live_join = $attrs->{_live_join_stack} || $our_attrs->{_live_join_stack}) {
186 foreach my $join (reverse @{$live_join}) {
187 $attrs->{$key} = { $join => $attrs->{$key} };
191 $our_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, delete $attrs->{$key});
194 $our_attrs->{join} = $self->_merge_attr(
195 $our_attrs->{join}, $attrs->{_live_join_h}
196 ) if ($attrs->{_live_join_h});
198 if (defined $our_attrs->{prefetch}) {
199 $our_attrs->{join} = $self->_merge_attr(
200 $our_attrs->{join}, $our_attrs->{prefetch}
204 my $new_attrs = { %{$our_attrs}, %{$attrs} };
207 (@_ == 1 || ref $_[0] eq "HASH")
211 ? $self->throw_exception("Odd number of arguments to search")
218 if (defined $where) {
219 $new_attrs->{where} = (
220 defined $new_attrs->{where}
223 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
224 } $where, $new_attrs->{where}
230 if (defined $having) {
231 $new_attrs->{having} = (
232 defined $new_attrs->{having}
235 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
236 } $having, $new_attrs->{having}
242 my $rs = (ref $self)->new($self->result_source, $new_attrs);
243 $rs->{_parent_source} = $self->{_parent_source} if $self->{_parent_source};
246 $rs->set_cache($rows);
251 =head2 search_literal
255 =item Arguments: $sql_fragment, @bind_values
257 =item Return Value: $resultset (scalar context), @row_objs (list context)
261 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
262 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
264 Pass a literal chunk of SQL to be added to the conditional part of the
270 my ($self, $cond, @vals) = @_;
271 my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {});
272 $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ];
273 return $self->search(\$cond, $attrs);
280 =item Arguments: @values | \%cols, \%attrs?
282 =item Return Value: $row_object
286 Finds a row based on its primary key or unique constraint. For example, to find
287 a row by its primary key:
289 my $cd = $schema->resultset('CD')->find(5);
291 You can also find a row by a specific unique constraint using the C<key>
292 attribute. For example:
294 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
295 key => 'cd_artist_title'
298 Additionally, you can specify the columns explicitly by name:
300 my $cd = $schema->resultset('CD')->find(
302 artist => 'Massive Attack',
303 title => 'Mezzanine',
305 { key => 'cd_artist_title' }
308 If the C<key> is specified as C<primary>, it searches only on the primary key.
310 If no C<key> is specified, it searches on all unique constraints defined on the
311 source, including the primary key.
313 See also L</find_or_create> and L</update_or_create>. For information on how to
314 declare unique constraints, see
315 L<DBIx::Class::ResultSource/add_unique_constraint>.
321 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
323 # Default to the primary key, but allow a specific key
324 my @cols = exists $attrs->{key}
325 ? $self->result_source->unique_constraint_columns($attrs->{key})
326 : $self->result_source->primary_columns;
327 $self->throw_exception(
328 "Can't find unless a primary key or unique constraint is defined"
331 # Parse out a hashref from input
333 if (ref $_[0] eq 'HASH') {
334 $input_query = { %{$_[0]} };
336 elsif (@_ == @cols) {
338 @{$input_query}{@cols} = @_;
341 # Compatibility: Allow e.g. find(id => $value)
342 carp "Find by key => value deprecated; please use a hashref instead";
346 my @unique_queries = $self->_unique_queries($input_query, $attrs);
348 # Handle cases where the ResultSet defines the query, or where the user is
350 my $query = @unique_queries ? \@unique_queries : $input_query;
354 my $rs = $self->search($query, $attrs);
355 return keys %{$rs->_resolved_attrs->{collapse}} ? $rs->next : $rs->single;
358 return keys %{$self->_resolved_attrs->{collapse}}
359 ? $self->search($query)->next
360 : $self->single($query);
366 # Build a list of queries which satisfy unique constraints.
368 sub _unique_queries {
369 my ($self, $query, $attrs) = @_;
371 my $alias = $self->{attrs}{alias};
372 my @constraint_names = exists $attrs->{key}
374 : $self->result_source->unique_constraint_names;
377 foreach my $name (@constraint_names) {
378 my @unique_cols = $self->result_source->unique_constraint_columns($name);
379 my $unique_query = $self->_build_unique_query($query, \@unique_cols);
381 my $num_query = scalar keys %$unique_query;
382 next unless $num_query;
384 # Add the ResultSet's alias
385 foreach my $col (grep { ! m/\./ } keys %$unique_query) {
386 $unique_query->{"$alias.$col"} = delete $unique_query->{$col};
389 # XXX: Assuming quite a bit about $self->{attrs}{where}
390 my $num_cols = scalar @unique_cols;
391 my $num_where = exists $self->{attrs}{where}
392 ? scalar keys %{ $self->{attrs}{where} }
394 push @unique_queries, $unique_query
395 if $num_query + $num_where == $num_cols;
398 return @unique_queries;
401 # _build_unique_query
403 # Constrain the specified query hash based on the specified column names.
405 sub _build_unique_query {
406 my ($self, $query, $unique_cols) = @_;
409 map { $_ => $query->{$_} }
410 grep { exists $query->{$_} }
415 =head2 search_related
419 =item Arguments: $rel, $cond, \%attrs?
421 =item Return Value: $new_resultset
425 $new_rs = $cd_rs->search_related('artist', {
429 Searches the specified relationship, optionally specifying a condition and
430 attributes for matching records. See L</ATTRIBUTES> for more information.
435 return shift->related_resultset(shift)->search(@_);
442 =item Arguments: none
444 =item Return Value: $cursor
448 Returns a storage-driven cursor to the given resultset. See
449 L<DBIx::Class::Cursor> for more information.
456 my $attrs = { %{$self->_resolved_attrs} };
457 return $self->{cursor}
458 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
459 $attrs->{where},$attrs);
466 =item Arguments: $cond?
468 =item Return Value: $row_object?
472 my $cd = $schema->resultset('CD')->single({ year => 2001 });
474 Inflates the first result without creating a cursor if the resultset has
475 any records in it; if not returns nothing. Used by L</find> as an optimisation.
477 Can optionally take an additional condition *only* - this is a fast-code-path
478 method; if you need to add extra joins or similar call ->search and then
479 ->single without a condition on the $rs returned from that.
484 my ($self, $where) = @_;
485 my $attrs = { %{$self->_resolved_attrs} };
487 if (defined $attrs->{where}) {
490 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
491 $where, delete $attrs->{where} ]
494 $attrs->{where} = $where;
498 unless ($self->_is_unique_query($attrs->{where})) {
499 carp "Query not guaranteed to return a single row"
500 . "; please declare your unique constraints or use search instead";
503 my @data = $self->result_source->storage->select_single(
504 $attrs->{from}, $attrs->{select},
505 $attrs->{where}, $attrs
508 return (@data ? $self->_construct_object(@data) : ());
513 # Try to determine if the specified query is guaranteed to be unique, based on
514 # the declared unique constraints.
516 sub _is_unique_query {
517 my ($self, $query) = @_;
519 my $collapsed = $self->_collapse_query($query);
520 my $alias = $self->{attrs}{alias};
522 foreach my $name ($self->result_source->unique_constraint_names) {
523 my @unique_cols = map {
525 } $self->result_source->unique_constraint_columns($name);
527 # Count the values for each unique column
528 my %seen = map { $_ => 0 } @unique_cols;
530 foreach my $key (keys %$collapsed) {
531 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
532 next unless exists $seen{$aliased}; # Additional constraints are okay
533 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
536 # If we get 0 or more than 1 value for a column, it's not necessarily unique
537 return 1 unless grep { $_ != 1 } values %seen;
545 # Recursively collapse the query, accumulating values for each column.
547 sub _collapse_query {
548 my ($self, $query, $collapsed) = @_;
552 if (ref $query eq 'ARRAY') {
553 foreach my $subquery (@$query) {
554 next unless ref $subquery; # -or
555 # warn "ARRAY: " . Dumper $subquery;
556 $collapsed = $self->_collapse_query($subquery, $collapsed);
559 elsif (ref $query eq 'HASH') {
560 if (keys %$query and (keys %$query)[0] eq '-and') {
561 foreach my $subquery (@{$query->{-and}}) {
562 # warn "HASH: " . Dumper $subquery;
563 $collapsed = $self->_collapse_query($subquery, $collapsed);
567 # warn "LEAF: " . Dumper $query;
568 foreach my $col (keys %$query) {
569 my $value = $query->{$col};
570 $collapsed->{$col}{$value}++;
582 =item Arguments: $cond?
584 =item Return Value: $resultsetcolumn
588 my $max_length = $rs->get_column('length')->max;
590 Returns a ResultSetColumn instance for $column based on $self
595 my ($self, $column) = @_;
596 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
604 =item Arguments: $cond, \%attrs?
606 =item Return Value: $resultset (scalar context), @row_objs (list context)
610 # WHERE title LIKE '%blue%'
611 $cd_rs = $rs->search_like({ title => '%blue%'});
613 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
614 that this is simply a convenience method. You most likely want to use
615 L</search> with specific operators.
617 For more information, see L<DBIx::Class::Manual::Cookbook>.
623 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
624 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
625 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
626 return $class->search($query, { %$attrs });
633 =item Arguments: $first, $last
635 =item Return Value: $resultset (scalar context), @row_objs (list context)
639 Returns a resultset or object list representing a subset of elements from the
640 resultset slice is called on. Indexes are from 0, i.e., to get the first
643 my ($one, $two, $three) = $rs->slice(0, 2);
648 my ($self, $min, $max) = @_;
649 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
650 $attrs->{offset} = $self->{attrs}{offset} || 0;
651 $attrs->{offset} += $min;
652 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
653 return $self->search(undef(), $attrs);
654 #my $slice = (ref $self)->new($self->result_source, $attrs);
655 #return (wantarray ? $slice->all : $slice);
662 =item Arguments: none
664 =item Return Value: $result?
668 Returns the next element in the resultset (C<undef> is there is none).
670 Can be used to efficiently iterate over records in the resultset:
672 my $rs = $schema->resultset('CD')->search;
673 while (my $cd = $rs->next) {
677 Note that you need to store the resultset object, and call C<next> on it.
678 Calling C<< resultset('Table')->next >> repeatedly will always return the
679 first record from the resultset.
685 if (my $cache = $self->get_cache) {
686 $self->{all_cache_position} ||= 0;
687 return $cache->[$self->{all_cache_position}++];
689 if ($self->{attrs}{cache}) {
690 $self->{all_cache_position} = 1;
691 return ($self->all)[0];
694 exists $self->{stashed_row}
695 ? @{delete $self->{stashed_row}}
696 : $self->cursor->next
698 return unless (@row);
699 return $self->_construct_object(@row);
702 sub _resolved_attrs {
704 return $self->{_attrs} if $self->{_attrs};
706 my $attrs = { %{$self->{attrs}||{}} };
707 my $source = $self->{_parent_source} || $self->{result_source};
708 my $alias = $attrs->{_orig_alias};
710 # XXX - lose storable dclone
711 my $record_filter = delete $attrs->{record_filter};
712 #$attrs = Storable::dclone($attrs || {}); # { %{ $attrs || {} } };
714 $attrs->{record_filter} = $record_filter if $record_filter;
716 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
717 if ($attrs->{columns}) {
719 } elsif (!$attrs->{select}) {
720 $attrs->{columns} = [ $self->{result_source}->columns ];
723 my $select_alias = $self->{attrs}{alias};
724 $attrs->{select} ||= [
725 map { m/\./ ? $_ : "${select_alias}.$_" } @{delete $attrs->{columns}}
728 map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{$attrs->{select}}
732 if ($adds = delete $attrs->{include_columns}) {
733 $adds = [$adds] unless ref $adds eq 'ARRAY';
734 push(@{$attrs->{select}}, @$adds);
735 push(@{$attrs->{as}}, map { m/([^.]+)$/; $1 } @$adds);
737 if ($adds = delete $attrs->{'+select'}) {
738 $adds = [$adds] unless ref $adds eq 'ARRAY';
739 push(@{$attrs->{select}}, map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds);
741 if (my $adds = delete $attrs->{'+as'}) {
742 $adds = [$adds] unless ref $adds eq 'ARRAY';
743 push(@{$attrs->{as}}, @$adds);
746 $attrs->{from} ||= [ { $alias => $source->from } ];
747 $attrs->{seen_join} ||= {};
748 if (my $join = delete $attrs->{join}) {
749 push(@{$attrs->{from}},
750 $source->resolve_join($join, $alias, $attrs->{seen_join})
754 $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct};
755 if ($attrs->{order_by}) {
756 $attrs->{order_by} = [ $attrs->{order_by} ] unless ref $attrs->{order_by};
758 $attrs->{order_by} ||= [];
761 my $collapse = $attrs->{collapse} || {};
762 if (my $prefetch = delete $attrs->{prefetch}) {
764 foreach my $p (ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch)) {
765 # bring joins back to level of current class
766 $p = $self->_reduce_joins($p, $attrs) if $attrs->{_live_join_stack};
768 my @prefetch = $self->result_source->resolve_prefetch(
769 $p, $alias, {}, \@pre_order, $collapse
771 push(@{$attrs->{select}}, map { $_->[0] } @prefetch);
772 push(@{$attrs->{as}}, map { $_->[1] } @prefetch);
775 push(@{$attrs->{order_by}}, @pre_order);
777 $attrs->{collapse} = $collapse;
779 return $self->{_attrs} = $attrs;
783 my ($self, $a, $b) = @_;
786 if (ref $b eq 'HASH' && ref $a eq 'HASH') {
787 foreach my $key (keys %{$b}) {
788 if (exists $a->{$key}) {
789 $a->{$key} = $self->_merge_attr($a->{$key}, $b->{$key});
791 $a->{$key} = $b->{$key};
796 $a = [$a] unless ref $a eq 'ARRAY';
797 $b = [$b] unless ref $b eq 'ARRAY';
801 foreach my $x ($a, $b) {
802 foreach my $element (@{$x}) {
803 if (ref $element eq 'HASH') {
804 $hash = $self->_merge_attr($hash, $element);
805 } elsif (ref $element eq 'ARRAY') {
806 push(@array, @{$element});
808 push(@array, $element) unless $b == $x
809 && grep { $_ eq $element } @array;
814 @array = grep { !exists $hash->{$_} } @array;
825 # bring the joins (which are from the original class) to the level
826 # of the current class so that we can resolve them properly
828 my ($self, $p, $attrs) = @_;
831 foreach my $join (@{$attrs->{_live_join_stack}}) {
832 if (ref $p eq 'HASH') {
833 return undef unless exists $p->{$join};
835 } elsif (ref $p eq 'ARRAY') {
836 foreach my $pe (@{$p}) {
837 return undef if $pe eq $join;
838 if (ref $pe eq 'HASH' && exists $pe->{$join}) {
851 sub _construct_object {
852 my ($self, @row) = @_;
853 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row);
854 my $new = $self->result_class->inflate_result($self->result_source, @$info);
855 $new = $self->{_attrs}{record_filter}->($new)
856 if exists $self->{_attrs}{record_filter};
860 sub _collapse_result {
861 my ($self, $as, $row, $prefix) = @_;
866 foreach my $this_as (@$as) {
867 my $val = shift @copy;
868 if (defined $prefix) {
869 if ($this_as =~ m/^\Q${prefix}.\E(.+)$/) {
871 $remain =~ /^(?:(.*)\.)?([^.]+)$/;
872 $const{$1||''}{$2} = $val;
875 $this_as =~ /^(?:(.*)\.)?([^.]+)$/;
876 $const{$1||''}{$2} = $val;
880 my $alias = $self->{attrs}{alias};
881 my $info = [ {}, {} ];
882 foreach my $key (keys %const) {
883 if (length $key && $key ne $alias) {
885 my @parts = split(/\./, $key);
886 foreach my $p (@parts) {
887 $target = $target->[1]->{$p} ||= [];
889 $target->[0] = $const{$key};
891 $info->[0] = $const{$key};
896 if (defined $prefix) {
898 m/^\Q${prefix}.\E(.+)$/ ? ($1) : ()
899 } keys %{$self->{_attrs}{collapse}}
901 @collapse = keys %{$self->{_attrs}{collapse}};
905 my ($c) = sort { length $a <=> length $b } @collapse;
907 foreach my $p (split(/\./, $c)) {
908 $target = $target->[1]->{$p} ||= [];
910 my $c_prefix = (defined($prefix) ? "${prefix}.${c}" : $c);
911 my @co_key = @{$self->{_attrs}{collapse}{$c_prefix}};
912 my $tree = $self->_collapse_result($as, $row, $c_prefix);
913 my %co_check = map { ($_, $tree->[0]->{$_}); } @co_key;
919 !defined($tree->[0]->{$_}) || $co_check{$_} ne $tree->[0]->{$_}
924 last unless (@raw = $self->cursor->next);
925 $row = $self->{stashed_row} = \@raw;
926 $tree = $self->_collapse_result($as, $row, $c_prefix);
928 @$target = (@final ? @final : [ {}, {} ]);
929 # single empty result to indicate an empty prefetched has_many
932 #print "final info: " . Dumper($info);
940 =item Arguments: $result_source?
942 =item Return Value: $result_source
946 An accessor for the primary ResultSource object from which this ResultSet
956 =item Arguments: $cond, \%attrs??
958 =item Return Value: $count
962 Performs an SQL C<COUNT> with the same query as the resultset was built
963 with to find the number of elements. If passed arguments, does a search
964 on the resultset and counts the results of that.
966 Note: When using C<count> with C<group_by>, L<DBIX::Class> emulates C<GROUP BY>
967 using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do
968 not support C<DISTINCT> with multiple columns. If you are using such a
969 database, you should only use columns from the main table in your C<group_by>
976 return $self->search(@_)->count if @_ and defined $_[0];
977 return scalar @{ $self->get_cache } if $self->get_cache;
978 my $count = $self->_count;
979 return 0 unless $count;
981 $count -= $self->{attrs}{offset} if $self->{attrs}{offset};
982 $count = $self->{attrs}{rows} if
983 $self->{attrs}{rows} and $self->{attrs}{rows} < $count;
987 sub _count { # Separated out so pager can get the full count
989 my $select = { count => '*' };
991 my $attrs = { %{$self->_resolved_attrs} };
992 if (my $group_by = delete $attrs->{group_by}) {
993 delete $attrs->{having};
994 my @distinct = (ref $group_by ? @$group_by : ($group_by));
995 # todo: try CONCAT for multi-column pk
996 my @pk = $self->result_source->primary_columns;
998 my $alias = $attrs->{_orig_alias};
999 foreach my $column (@distinct) {
1000 if ($column =~ qr/^(?:\Q${alias}.\E)?$pk[0]$/) {
1001 @distinct = ($column);
1007 $select = { count => { distinct => \@distinct } };
1010 $attrs->{select} = $select;
1011 $attrs->{as} = [qw/count/];
1013 # offset, order by and page are not needed to count. record_filter is cdbi
1014 delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/;
1015 my $tmp_rs = (ref $self)->new($self->result_source, $attrs);
1016 $tmp_rs->{_parent_source} = $self->{_parent_source} if $self->{_parent_source};
1017 #XXX - hack to pass through parent of related resultsets
1019 my ($count) = $tmp_rs->cursor->next;
1023 =head2 count_literal
1027 =item Arguments: $sql_fragment, @bind_values
1029 =item Return Value: $count
1033 Counts the results in a literal query. Equivalent to calling L</search_literal>
1034 with the passed arguments, then L</count>.
1038 sub count_literal { shift->search_literal(@_)->count; }
1044 =item Arguments: none
1046 =item Return Value: @objects
1050 Returns all elements in the resultset. Called implicitly if the resultset
1051 is returned in list context.
1057 return @{ $self->get_cache } if $self->get_cache;
1061 # TODO: don't call resolve here
1062 if (keys %{$self->_resolved_attrs->{collapse}}) {
1063 # if ($self->{attrs}{prefetch}) {
1064 # Using $self->cursor->all is really just an optimisation.
1065 # If we're collapsing has_many prefetches it probably makes
1066 # very little difference, and this is cleaner than hacking
1067 # _construct_object to survive the approach
1068 my @row = $self->cursor->next;
1070 push(@obj, $self->_construct_object(@row));
1071 @row = (exists $self->{stashed_row}
1072 ? @{delete $self->{stashed_row}}
1073 : $self->cursor->next);
1076 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1079 $self->set_cache(\@obj) if $self->{attrs}{cache};
1087 =item Arguments: none
1089 =item Return Value: $self
1093 Resets the resultset's cursor, so you can iterate through the elements again.
1099 delete $self->{_attrs} if exists $self->{_attrs};
1100 $self->{all_cache_position} = 0;
1101 $self->cursor->reset;
1109 =item Arguments: none
1111 =item Return Value: $object?
1115 Resets the resultset and returns an object for the first result (if the
1116 resultset returns anything).
1121 return $_[0]->reset->next;
1124 # _cond_for_update_delete
1126 # update/delete require the condition to be modified to handle
1127 # the differing SQL syntax available. This transforms the $self->{cond}
1128 # appropriately, returning the new condition.
1130 sub _cond_for_update_delete {
1134 # No-op. No condition, we're updating/deleting everything
1135 return $cond unless ref $self->{cond};
1137 if (ref $self->{cond} eq 'ARRAY') {
1141 foreach my $key (keys %{$_}) {
1143 $hash{$1} = $_->{$key};
1149 elsif (ref $self->{cond} eq 'HASH') {
1150 if ((keys %{$self->{cond}})[0] eq '-and') {
1153 my @cond = @{$self->{cond}{-and}};
1154 for (my $i = 0; $i < @cond; $i++) {
1155 my $entry = $cond[$i];
1158 if (ref $entry eq 'HASH') {
1159 foreach my $key (keys %{$entry}) {
1161 $hash{$1} = $entry->{$key};
1165 $entry =~ /([^.]+)$/;
1166 $hash{$1} = $cond[++$i];
1169 push @{$cond->{-and}}, \%hash;
1173 foreach my $key (keys %{$self->{cond}}) {
1175 $cond->{$1} = $self->{cond}{$key};
1180 $self->throw_exception(
1181 "Can't update/delete on resultset with condition unless hash or array"
1193 =item Arguments: \%values
1195 =item Return Value: $storage_rv
1199 Sets the specified columns in the resultset to the supplied values in a
1200 single query. Return value will be true if the update succeeded or false
1201 if no records were updated; exact type of success value is storage-dependent.
1206 my ($self, $values) = @_;
1207 $self->throw_exception("Values for update must be a hash")
1208 unless ref $values eq 'HASH';
1210 my $cond = $self->_cond_for_update_delete;
1212 return $self->result_source->storage->update(
1213 $self->result_source->from, $values, $cond
1221 =item Arguments: \%values
1223 =item Return Value: 1
1227 Fetches all objects and updates them one at a time. Note that C<update_all>
1228 will run DBIC cascade triggers, while L</update> will not.
1233 my ($self, $values) = @_;
1234 $self->throw_exception("Values for update must be a hash")
1235 unless ref $values eq 'HASH';
1236 foreach my $obj ($self->all) {
1237 $obj->set_columns($values)->update;
1246 =item Arguments: none
1248 =item Return Value: 1
1252 Deletes the contents of the resultset from its result source. Note that this
1253 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1261 my $cond = $self->_cond_for_update_delete;
1263 $self->result_source->storage->delete($self->result_source->from, $cond);
1271 =item Arguments: none
1273 =item Return Value: 1
1277 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1278 will run DBIC cascade triggers, while L</delete> will not.
1284 $_->delete for $self->all;
1292 =item Arguments: none
1294 =item Return Value: $pager
1298 Return Value a L<Data::Page> object for the current resultset. Only makes
1299 sense for queries with a C<page> attribute.
1305 my $attrs = $self->{attrs};
1306 $self->throw_exception("Can't create pager for non-paged rs")
1307 unless $self->{attrs}{page};
1308 $attrs->{rows} ||= 10;
1309 return $self->{pager} ||= Data::Page->new(
1310 $self->_count, $attrs->{rows}, $self->{attrs}{page});
1317 =item Arguments: $page_number
1319 =item Return Value: $rs
1323 Returns a resultset for the $page_number page of the resultset on which page
1324 is called, where each page contains a number of rows equal to the 'rows'
1325 attribute set on the resultset (10 by default).
1330 my ($self, $page) = @_;
1331 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1338 =item Arguments: \%vals
1340 =item Return Value: $object
1344 Creates an object in the resultset's result class and returns it.
1349 my ($self, $values) = @_;
1350 $self->throw_exception( "new_result needs a hash" )
1351 unless (ref $values eq 'HASH');
1352 $self->throw_exception(
1353 "Can't abstract implicit construct, condition not a hash"
1354 ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
1356 my $alias = $self->{attrs}{_orig_alias};
1357 foreach my $key (keys %{$self->{cond}||{}}) {
1358 $new{$1} = $self->{cond}{$key} if ($key =~ m/^(?:\Q${alias}.\E)?([^.]+)$/);
1360 my $obj = $self->result_class->new(\%new);
1361 $obj->result_source($self->result_source) if $obj->can('result_source');
1369 =item Arguments: \%vals, \%attrs?
1371 =item Return Value: $object
1375 Find an existing record from this resultset. If none exists, instantiate a new
1376 result object and return it. The object will not be saved into your storage
1377 until you call L<DBIx::Class::Row/insert> on it.
1379 If you want objects to be saved immediately, use L</find_or_create> instead.
1385 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1386 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1387 my $exists = $self->find($hash, $attrs);
1388 return defined $exists ? $exists : $self->new_result($hash);
1395 =item Arguments: \%vals
1397 =item Return Value: $object
1401 Inserts a record into the resultset and returns the object representing it.
1403 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
1408 my ($self, $attrs) = @_;
1409 $self->throw_exception( "create needs a hashref" )
1410 unless ref $attrs eq 'HASH';
1411 return $self->new_result($attrs)->insert;
1414 =head2 find_or_create
1418 =item Arguments: \%vals, \%attrs?
1420 =item Return Value: $object
1424 $class->find_or_create({ key => $val, ... });
1426 Tries to find a record based on its primary key or unique constraint; if none
1427 is found, creates one and returns that instead.
1429 my $cd = $schema->resultset('CD')->find_or_create({
1431 artist => 'Massive Attack',
1432 title => 'Mezzanine',
1436 Also takes an optional C<key> attribute, to search by a specific key or unique
1437 constraint. For example:
1439 my $cd = $schema->resultset('CD')->find_or_create(
1441 artist => 'Massive Attack',
1442 title => 'Mezzanine',
1444 { key => 'cd_artist_title' }
1447 See also L</find> and L</update_or_create>. For information on how to declare
1448 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1452 sub find_or_create {
1454 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1455 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1456 my $exists = $self->find($hash, $attrs);
1457 return defined $exists ? $exists : $self->create($hash);
1460 =head2 update_or_create
1464 =item Arguments: \%col_values, { key => $unique_constraint }?
1466 =item Return Value: $object
1470 $class->update_or_create({ col => $val, ... });
1472 First, searches for an existing row matching one of the unique constraints
1473 (including the primary key) on the source of this resultset. If a row is
1474 found, updates it with the other given column values. Otherwise, creates a new
1477 Takes an optional C<key> attribute to search on a specific unique constraint.
1480 # In your application
1481 my $cd = $schema->resultset('CD')->update_or_create(
1483 artist => 'Massive Attack',
1484 title => 'Mezzanine',
1487 { key => 'cd_artist_title' }
1490 If no C<key> is specified, it searches on all unique constraints defined on the
1491 source, including the primary key.
1493 If the C<key> is specified as C<primary>, it searches only on the primary key.
1495 See also L</find> and L</find_or_create>. For information on how to declare
1496 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1500 sub update_or_create {
1502 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1503 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
1505 my $row = $self->find($cond);
1507 $row->update($cond);
1511 return $self->create($cond);
1518 =item Arguments: none
1520 =item Return Value: \@cache_objects?
1524 Gets the contents of the cache for the resultset, if the cache is set.
1536 =item Arguments: \@cache_objects
1538 =item Return Value: \@cache_objects
1542 Sets the contents of the cache for the resultset. Expects an arrayref
1543 of objects of the same class as those produced by the resultset. Note that
1544 if the cache is set the resultset will return the cached objects rather
1545 than re-querying the database even if the cache attr is not set.
1550 my ( $self, $data ) = @_;
1551 $self->throw_exception("set_cache requires an arrayref")
1552 if defined($data) && (ref $data ne 'ARRAY');
1553 $self->{all_cache} = $data;
1560 =item Arguments: none
1562 =item Return Value: []
1566 Clears the cache for the resultset.
1571 shift->set_cache(undef);
1574 =head2 related_resultset
1578 =item Arguments: $relationship_name
1580 =item Return Value: $resultset
1584 Returns a related resultset for the supplied relationship name.
1586 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
1590 sub related_resultset {
1591 my ($self, $rel) = @_;
1593 $self->{related_resultsets} ||= {};
1594 return $self->{related_resultsets}{$rel} ||= do {
1595 my $rel_obj = $self->result_source->relationship_info($rel);
1597 $self->throw_exception(
1598 "search_related: result source '" . $self->result_source->name .
1599 "' has no such relationship $rel")
1602 my @live_join_stack = @{$self->{attrs}{_live_join_stack}||[]};
1604 # XXX mst: I'm sure this is wrong, somehow
1605 # something with complex joins early on could die on search_rel
1606 # followed by a prefetch. I think. need a test case.
1608 my $join_count = scalar(grep { $_ eq $rel } @live_join_stack);
1609 my $alias = $join_count ? join('_', $rel, $join_count+1) : $rel;
1611 push(@live_join_stack, $rel);
1613 my $rs = $self->result_source->schema->resultset($rel_obj->{class})->search(
1618 _live_join_stack => \@live_join_stack,
1619 _parent_attrs => $self->{attrs}}
1622 # keep reference of the original resultset
1623 $rs->{_parent_source} = $self->{_parent_source} || $self->result_source;
1629 =head2 throw_exception
1631 See L<DBIx::Class::Schema/throw_exception> for details.
1635 sub throw_exception {
1637 $self->result_source->schema->throw_exception(@_);
1640 # XXX: FIXME: Attributes docs need clearing up
1644 The resultset takes various attributes that modify its behavior. Here's an
1651 =item Value: ($order_by | \@order_by)
1655 Which column(s) to order the results by. This is currently passed
1656 through directly to SQL, so you can give e.g. C<year DESC> for a
1657 descending order on the column `year'.
1659 Please note that if you have quoting enabled (see
1660 L<DBIx::Class::Storage/quote_char>) you will need to do C<\'year DESC' > to
1661 specify an order. (The scalar ref causes it to be passed as raw sql to the DB,
1662 so you will need to manually quote things as appropriate.)
1668 =item Value: \@columns
1672 Shortcut to request a particular set of columns to be retrieved. Adds
1673 C<me.> onto the start of any column without a C<.> in it and sets C<select>
1674 from that, then auto-populates C<as> from C<select> as normal. (You may also
1675 use the C<cols> attribute, as in earlier versions of DBIC.)
1677 =head2 include_columns
1681 =item Value: \@columns
1685 Shortcut to include additional columns in the returned results - for example
1687 $schema->resultset('CD')->search(undef, {
1688 include_columns => ['artist.name'],
1692 would return all CDs and include a 'name' column to the information
1693 passed to object inflation
1699 =item Value: \@select_columns
1703 Indicates which columns should be selected from the storage. You can use
1704 column names, or in the case of RDBMS back ends, function or stored procedure
1707 $rs = $schema->resultset('Employee')->search(undef, {
1710 { count => 'employeeid' },
1715 When you use function/stored procedure names and do not supply an C<as>
1716 attribute, the column names returned are storage-dependent. E.g. MySQL would
1717 return a column named C<count(employeeid)> in the above example.
1723 Indicates additional columns to be selected from storage. Works the same as
1724 L<select> but adds columns to the selection.
1732 Indicates additional column names for those added via L<+select>.
1740 =item Value: \@inflation_names
1744 Indicates column names for object inflation. This is used in conjunction with
1745 C<select>, usually when C<select> contains one or more function or stored
1748 $rs = $schema->resultset('Employee')->search(undef, {
1751 { count => 'employeeid' }
1753 as => ['name', 'employee_count'],
1756 my $employee = $rs->first(); # get the first Employee
1758 If the object against which the search is performed already has an accessor
1759 matching a column name specified in C<as>, the value can be retrieved using
1760 the accessor as normal:
1762 my $name = $employee->name();
1764 If on the other hand an accessor does not exist in the object, you need to
1765 use C<get_column> instead:
1767 my $employee_count = $employee->get_column('employee_count');
1769 You can create your own accessors if required - see
1770 L<DBIx::Class::Manual::Cookbook> for details.
1772 Please note: This will NOT insert an C<AS employee_count> into the SQL statement
1773 produced, it is used for internal access only. Thus attempting to use the accessor
1774 in an C<order_by> clause or similar will fail misrably.
1780 =item Value: ($rel_name | \@rel_names | \%rel_names)
1784 Contains a list of relationships that should be joined for this query. For
1787 # Get CDs by Nine Inch Nails
1788 my $rs = $schema->resultset('CD')->search(
1789 { 'artist.name' => 'Nine Inch Nails' },
1790 { join => 'artist' }
1793 Can also contain a hash reference to refer to the other relation's relations.
1796 package MyApp::Schema::Track;
1797 use base qw/DBIx::Class/;
1798 __PACKAGE__->table('track');
1799 __PACKAGE__->add_columns(qw/trackid cd position title/);
1800 __PACKAGE__->set_primary_key('trackid');
1801 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
1804 # In your application
1805 my $rs = $schema->resultset('Artist')->search(
1806 { 'track.title' => 'Teardrop' },
1808 join => { cd => 'track' },
1809 order_by => 'artist.name',
1813 If the same join is supplied twice, it will be aliased to <rel>_2 (and
1814 similarly for a third time). For e.g.
1816 my $rs = $schema->resultset('Artist')->search({
1817 'cds.title' => 'Down to Earth',
1818 'cds_2.title' => 'Popular',
1820 join => [ qw/cds cds/ ],
1823 will return a set of all artists that have both a cd with title 'Down
1824 to Earth' and a cd with title 'Popular'.
1826 If you want to fetch related objects from other tables as well, see C<prefetch>
1833 =item Value: ($rel_name | \@rel_names | \%rel_names)
1837 Contains one or more relationships that should be fetched along with the main
1838 query (when they are accessed afterwards they will have already been
1839 "prefetched"). This is useful for when you know you will need the related
1840 objects, because it saves at least one query:
1842 my $rs = $schema->resultset('Tag')->search(
1851 The initial search results in SQL like the following:
1853 SELECT tag.*, cd.*, artist.* FROM tag
1854 JOIN cd ON tag.cd = cd.cdid
1855 JOIN artist ON cd.artist = artist.artistid
1857 L<DBIx::Class> has no need to go back to the database when we access the
1858 C<cd> or C<artist> relationships, which saves us two SQL statements in this
1861 Simple prefetches will be joined automatically, so there is no need
1862 for a C<join> attribute in the above search. If you're prefetching to
1863 depth (e.g. { cd => { artist => 'label' } or similar), you'll need to
1864 specify the join as well.
1866 C<prefetch> can be used with the following relationship types: C<belongs_to>,
1867 C<has_one> (or if you're using C<add_relationship>, any relationship declared
1868 with an accessor type of 'single' or 'filter').
1878 Makes the resultset paged and specifies the page to retrieve. Effectively
1879 identical to creating a non-pages resultset and then calling ->page($page)
1882 If L<rows> attribute is not specified it defualts to 10 rows per page.
1892 Specifes the maximum number of rows for direct retrieval or the number of
1893 rows per page if the page attribute or method is used.
1899 =item Value: $offset
1903 Specifies the (zero-based) row number for the first row to be returned, or the
1904 of the first row of the first page if paging is used.
1910 =item Value: \@columns
1914 A arrayref of columns to group by. Can include columns of joined tables.
1916 group_by => [qw/ column1 column2 ... /]
1922 =item Value: $condition
1926 HAVING is a select statement attribute that is applied between GROUP BY and
1927 ORDER BY. It is applied to the after the grouping calculations have been
1930 having => { 'count(employee)' => { '>=', 100 } }
1936 =item Value: (0 | 1)
1940 Set to 1 to group by all columns.
1946 Adds to the WHERE clause.
1948 # only return rows WHERE deleted IS NULL for all searches
1949 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
1951 Can be overridden by passing C<{ where => undef }> as an attribute
1958 Set to 1 to cache search results. This prevents extra SQL queries if you
1959 revisit rows in your ResultSet:
1961 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
1963 while( my $artist = $resultset->next ) {
1967 $rs->first; # without cache, this would issue a query
1969 By default, searches are not cached.
1971 For more examples of using these attributes, see
1972 L<DBIx::Class::Manual::Cookbook>.
1978 =item Value: \@from_clause
1982 The C<from> attribute gives you manual control over the C<FROM> clause of SQL
1983 statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
1986 NOTE: Use this on your own risk. This allows you to shoot off your foot!
1988 C<join> will usually do what you need and it is strongly recommended that you
1989 avoid using C<from> unless you cannot achieve the desired result using C<join>.
1990 And we really do mean "cannot", not just tried and failed. Attempting to use
1991 this because you're having problems with C<join> is like trying to use x86
1992 ASM because you've got a syntax error in your C. Trust us on this.
1994 Now, if you're still really, really sure you need to use this (and if you're
1995 not 100% sure, ask the mailing list first), here's an explanation of how this
1998 The syntax is as follows -
2001 { <alias1> => <table1> },
2003 { <alias2> => <table2>, -join_type => 'inner|left|right' },
2004 [], # nested JOIN (optional)
2005 { <table1.column1> => <table2.column2>, ... (more conditions) },
2007 # More of the above [ ] may follow for additional joins
2014 ON <table1.column1> = <table2.column2>
2015 <more joins may follow>
2017 An easy way to follow the examples below is to remember the following:
2019 Anything inside "[]" is a JOIN
2020 Anything inside "{}" is a condition for the enclosing JOIN
2022 The following examples utilize a "person" table in a family tree application.
2023 In order to express parent->child relationships, this table is self-joined:
2025 # Person->belongs_to('father' => 'Person');
2026 # Person->belongs_to('mother' => 'Person');
2028 C<from> can be used to nest joins. Here we return all children with a father,
2029 then search against all mothers of those children:
2031 $rs = $schema->resultset('Person')->search(
2034 alias => 'mother', # alias columns in accordance with "from"
2036 { mother => 'person' },
2039 { child => 'person' },
2041 { father => 'person' },
2042 { 'father.person_id' => 'child.father_id' }
2045 { 'mother.person_id' => 'child.mother_id' }
2052 # SELECT mother.* FROM person mother
2055 # JOIN person father
2056 # ON ( father.person_id = child.father_id )
2058 # ON ( mother.person_id = child.mother_id )
2060 The type of any join can be controlled manually. To search against only people
2061 with a father in the person table, we could explicitly use C<INNER JOIN>:
2063 $rs = $schema->resultset('Person')->search(
2066 alias => 'child', # alias columns in accordance with "from"
2068 { child => 'person' },
2070 { father => 'person', -join_type => 'inner' },
2071 { 'father.id' => 'child.father_id' }
2078 # SELECT child.* FROM person child
2079 # INNER JOIN person father ON child.father_id = father.id