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 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};
240 $rs->set_cache($rows);
245 =head2 search_literal
249 =item Arguments: $sql_fragment, @bind_values
251 =item Return Value: $resultset (scalar context), @row_objs (list context)
255 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
256 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
258 Pass a literal chunk of SQL to be added to the conditional part of the
264 my ($self, $cond, @vals) = @_;
265 my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {});
266 $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ];
267 return $self->search(\$cond, $attrs);
274 =item Arguments: @values | \%cols, \%attrs?
276 =item Return Value: $row_object
280 Finds a row based on its primary key or unique constraint. For example, to find
281 a row by its primary key:
283 my $cd = $schema->resultset('CD')->find(5);
285 You can also find a row by a specific unique constraint using the C<key>
286 attribute. For example:
288 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
289 key => 'cd_artist_title'
292 Additionally, you can specify the columns explicitly by name:
294 my $cd = $schema->resultset('CD')->find(
296 artist => 'Massive Attack',
297 title => 'Mezzanine',
299 { key => 'cd_artist_title' }
302 If the C<key> is specified as C<primary>, it searches only on the primary key.
304 If no C<key> is specified, it searches on all unique constraints defined on the
305 source, including the primary key.
307 See also L</find_or_create> and L</update_or_create>. For information on how to
308 declare unique constraints, see
309 L<DBIx::Class::ResultSource/add_unique_constraint>.
315 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
317 # Default to the primary key, but allow a specific key
318 my @cols = exists $attrs->{key}
319 ? $self->result_source->unique_constraint_columns($attrs->{key})
320 : $self->result_source->primary_columns;
321 $self->throw_exception(
322 "Can't find unless a primary key or unique constraint is defined"
325 # Parse out a hashref from input
327 if (ref $_[0] eq 'HASH') {
328 $input_query = { %{$_[0]} };
330 elsif (@_ == @cols) {
332 @{$input_query}{@cols} = @_;
335 # Compatibility: Allow e.g. find(id => $value)
336 carp "Find by key => value deprecated; please use a hashref instead";
340 my @unique_queries = $self->_unique_queries($input_query, $attrs);
342 # Handle cases where the ResultSet defines the query, or where the user is
344 my $query = @unique_queries ? \@unique_queries : $input_query;
348 my $rs = $self->search($query, $attrs);
349 return keys %{$rs->_resolved_attrs->{collapse}} ? $rs->next : $rs->single;
352 return keys %{$self->_resolved_attrs->{collapse}}
353 ? $self->search($query)->next
354 : $self->single($query);
360 # Build a list of queries which satisfy unique constraints.
362 sub _unique_queries {
363 my ($self, $query, $attrs) = @_;
365 my $alias = $self->{attrs}{alias};
366 my @constraint_names = exists $attrs->{key}
368 : $self->result_source->unique_constraint_names;
371 foreach my $name (@constraint_names) {
372 my @unique_cols = $self->result_source->unique_constraint_columns($name);
373 my $unique_query = $self->_build_unique_query($query, \@unique_cols);
375 my $num_query = scalar keys %$unique_query;
376 next unless $num_query;
378 # Add the ResultSet's alias
379 foreach my $col (grep { ! m/\./ } keys %$unique_query) {
380 $unique_query->{"$alias.$col"} = delete $unique_query->{$col};
383 # XXX: Assuming quite a bit about $self->{attrs}{where}
384 my $num_cols = scalar @unique_cols;
385 my $num_where = exists $self->{attrs}{where}
386 ? scalar keys %{ $self->{attrs}{where} }
388 push @unique_queries, $unique_query
389 if $num_query + $num_where == $num_cols;
392 return @unique_queries;
395 # _build_unique_query
397 # Constrain the specified query hash based on the specified column names.
399 sub _build_unique_query {
400 my ($self, $query, $unique_cols) = @_;
403 map { $_ => $query->{$_} }
404 grep { exists $query->{$_} }
409 =head2 search_related
413 =item Arguments: $rel, $cond, \%attrs?
415 =item Return Value: $new_resultset
419 $new_rs = $cd_rs->search_related('artist', {
423 Searches the specified relationship, optionally specifying a condition and
424 attributes for matching records. See L</ATTRIBUTES> for more information.
429 return shift->related_resultset(shift)->search(@_);
436 =item Arguments: none
438 =item Return Value: $cursor
442 Returns a storage-driven cursor to the given resultset. See
443 L<DBIx::Class::Cursor> for more information.
450 my $attrs = { %{$self->_resolved_attrs} };
451 return $self->{cursor}
452 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
453 $attrs->{where},$attrs);
460 =item Arguments: $cond?
462 =item Return Value: $row_object?
466 my $cd = $schema->resultset('CD')->single({ year => 2001 });
468 Inflates the first result without creating a cursor if the resultset has
469 any records in it; if not returns nothing. Used by L</find> as an optimisation.
471 Can optionally take an additional condition *only* - this is a fast-code-path
472 method; if you need to add extra joins or similar call ->search and then
473 ->single without a condition on the $rs returned from that.
478 my ($self, $where) = @_;
479 my $attrs = { %{$self->_resolved_attrs} };
481 if (defined $attrs->{where}) {
484 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
485 $where, delete $attrs->{where} ]
488 $attrs->{where} = $where;
492 unless ($self->_is_unique_query($attrs->{where})) {
493 carp "Query not guaranteed to return a single row"
494 . "; please declare your unique constraints or use search instead";
497 my @data = $self->result_source->storage->select_single(
498 $attrs->{from}, $attrs->{select},
499 $attrs->{where}, $attrs
502 return (@data ? $self->_construct_object(@data) : ());
507 # Try to determine if the specified query is guaranteed to be unique, based on
508 # the declared unique constraints.
510 sub _is_unique_query {
511 my ($self, $query) = @_;
513 my $collapsed = $self->_collapse_query($query);
514 my $alias = $self->{attrs}{alias};
516 foreach my $name ($self->result_source->unique_constraint_names) {
517 my @unique_cols = map {
519 } $self->result_source->unique_constraint_columns($name);
521 # Count the values for each unique column
522 my %seen = map { $_ => 0 } @unique_cols;
524 foreach my $key (keys %$collapsed) {
525 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
526 next unless exists $seen{$aliased}; # Additional constraints are okay
527 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
530 # If we get 0 or more than 1 value for a column, it's not necessarily unique
531 return 1 unless grep { $_ != 1 } values %seen;
539 # Recursively collapse the query, accumulating values for each column.
541 sub _collapse_query {
542 my ($self, $query, $collapsed) = @_;
546 if (ref $query eq 'ARRAY') {
547 foreach my $subquery (@$query) {
548 next unless ref $subquery; # -or
549 # warn "ARRAY: " . Dumper $subquery;
550 $collapsed = $self->_collapse_query($subquery, $collapsed);
553 elsif (ref $query eq 'HASH') {
554 if (keys %$query and (keys %$query)[0] eq '-and') {
555 foreach my $subquery (@{$query->{-and}}) {
556 # warn "HASH: " . Dumper $subquery;
557 $collapsed = $self->_collapse_query($subquery, $collapsed);
561 # warn "LEAF: " . Dumper $query;
562 foreach my $col (keys %$query) {
563 my $value = $query->{$col};
564 $collapsed->{$col}{$value}++;
576 =item Arguments: $cond?
578 =item Return Value: $resultsetcolumn
582 my $max_length = $rs->get_column('length')->max;
584 Returns a ResultSetColumn instance for $column based on $self
589 my ($self, $column) = @_;
590 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
598 =item Arguments: $cond, \%attrs?
600 =item Return Value: $resultset (scalar context), @row_objs (list context)
604 # WHERE title LIKE '%blue%'
605 $cd_rs = $rs->search_like({ title => '%blue%'});
607 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
608 that this is simply a convenience method. You most likely want to use
609 L</search> with specific operators.
611 For more information, see L<DBIx::Class::Manual::Cookbook>.
617 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
618 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
619 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
620 return $class->search($query, { %$attrs });
627 =item Arguments: $first, $last
629 =item Return Value: $resultset (scalar context), @row_objs (list context)
633 Returns a resultset or object list representing a subset of elements from the
634 resultset slice is called on. Indexes are from 0, i.e., to get the first
637 my ($one, $two, $three) = $rs->slice(0, 2);
642 my ($self, $min, $max) = @_;
643 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
644 $attrs->{offset} = $self->{attrs}{offset} || 0;
645 $attrs->{offset} += $min;
646 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
647 return $self->search(undef(), $attrs);
648 #my $slice = (ref $self)->new($self->result_source, $attrs);
649 #return (wantarray ? $slice->all : $slice);
656 =item Arguments: none
658 =item Return Value: $result?
662 Returns the next element in the resultset (C<undef> is there is none).
664 Can be used to efficiently iterate over records in the resultset:
666 my $rs = $schema->resultset('CD')->search;
667 while (my $cd = $rs->next) {
671 Note that you need to store the resultset object, and call C<next> on it.
672 Calling C<< resultset('Table')->next >> repeatedly will always return the
673 first record from the resultset.
679 if (my $cache = $self->get_cache) {
680 $self->{all_cache_position} ||= 0;
681 return $cache->[$self->{all_cache_position}++];
683 if ($self->{attrs}{cache}) {
684 $self->{all_cache_position} = 1;
685 return ($self->all)[0];
688 exists $self->{stashed_row}
689 ? @{delete $self->{stashed_row}}
690 : $self->cursor->next
692 return unless (@row);
693 return $self->_construct_object(@row);
696 sub _resolved_attrs {
698 return $self->{_attrs} if $self->{_attrs};
700 my $attrs = { %{$self->{attrs}||{}} };
701 my $source = $self->{_parent_source} || $self->{result_source};
702 my $alias = $attrs->{_orig_alias};
704 # XXX - lose storable dclone
705 my $record_filter = delete $attrs->{record_filter};
706 #$attrs = Storable::dclone($attrs || {}); # { %{ $attrs || {} } };
708 $attrs->{record_filter} = $record_filter if $record_filter;
710 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
711 if ($attrs->{columns}) {
713 } elsif (!$attrs->{select}) {
714 $attrs->{columns} = [ $self->{result_source}->columns ];
717 my $select_alias = $self->{attrs}{alias};
718 $attrs->{select} ||= [
719 map { m/\./ ? $_ : "${select_alias}.$_" } @{delete $attrs->{columns}}
722 map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{$attrs->{select}}
726 if ($adds = delete $attrs->{include_columns}) {
727 $adds = [$adds] unless ref $adds eq 'ARRAY';
728 push(@{$attrs->{select}}, @$adds);
729 push(@{$attrs->{as}}, map { m/([^.]+)$/; $1 } @$adds);
731 if ($adds = delete $attrs->{'+select'}) {
732 $adds = [$adds] unless ref $adds eq 'ARRAY';
733 push(@{$attrs->{select}}, map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds);
735 if (my $adds = delete $attrs->{'+as'}) {
736 $adds = [$adds] unless ref $adds eq 'ARRAY';
737 push(@{$attrs->{as}}, @$adds);
740 $attrs->{from} ||= [ { $alias => $source->from } ];
741 $attrs->{seen_join} ||= {};
742 if (exists $attrs->{join} || exists $attrs->{prefetch}) {
744 my $join = delete $attrs->{join} || {};
746 if (defined $attrs->{prefetch}) {
747 $join = $self->_merge_attr(
748 $join, $attrs->{prefetch}
752 push(@{$attrs->{from}},
753 $source->resolve_join($join, $alias, $attrs->{seen_join})
757 $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct};
758 if ($attrs->{order_by}) {
759 $attrs->{order_by} = [ $attrs->{order_by} ] unless ref $attrs->{order_by};
761 $attrs->{order_by} ||= [];
764 my $collapse = $attrs->{collapse} || {};
765 if (my $prefetch = delete $attrs->{prefetch}) {
767 foreach my $p (ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch)) {
768 # bring joins back to level of current class
769 $p = $self->_reduce_joins($p, $attrs) if $attrs->{_live_join_stack};
771 my @prefetch = $self->result_source->resolve_prefetch(
772 $p, $alias, {}, \@pre_order, $collapse
774 push(@{$attrs->{select}}, map { $_->[0] } @prefetch);
775 push(@{$attrs->{as}}, map { $_->[1] } @prefetch);
778 push(@{$attrs->{order_by}}, @pre_order);
780 $attrs->{collapse} = $collapse;
782 return $self->{_attrs} = $attrs;
786 my ($self, $a, $b) = @_;
789 if (ref $b eq 'HASH' && ref $a eq 'HASH') {
790 foreach my $key (keys %{$b}) {
791 if (exists $a->{$key}) {
792 $a->{$key} = $self->_merge_attr($a->{$key}, $b->{$key});
794 $a->{$key} = $b->{$key};
799 $a = [$a] unless ref $a eq 'ARRAY';
800 $b = [$b] unless ref $b eq 'ARRAY';
804 foreach my $x ($a, $b) {
805 foreach my $element (@{$x}) {
806 if (ref $element eq 'HASH') {
807 $hash = $self->_merge_attr($hash, $element);
808 } elsif (ref $element eq 'ARRAY') {
809 push(@array, @{$element});
811 push(@array, $element) unless $b == $x
812 && grep { $_ eq $element } @array;
817 @array = grep { !exists $hash->{$_} } @array;
828 # bring the joins (which are from the original class) to the level
829 # of the current class so that we can resolve them properly
831 my ($self, $p, $attrs) = @_;
834 foreach my $join (@{$attrs->{_live_join_stack}}) {
835 if (ref $p eq 'HASH') {
836 return undef unless exists $p->{$join};
838 } elsif (ref $p eq 'ARRAY') {
839 foreach my $pe (@{$p}) {
840 return undef if $pe eq $join;
841 if (ref $pe eq 'HASH' && exists $pe->{$join}) {
854 sub _construct_object {
855 my ($self, @row) = @_;
856 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row);
857 my $new = $self->result_class->inflate_result($self->result_source, @$info);
858 $new = $self->{_attrs}{record_filter}->($new)
859 if exists $self->{_attrs}{record_filter};
863 sub _collapse_result {
864 my ($self, $as, $row, $prefix) = @_;
869 foreach my $this_as (@$as) {
870 my $val = shift @copy;
871 if (defined $prefix) {
872 if ($this_as =~ m/^\Q${prefix}.\E(.+)$/) {
874 $remain =~ /^(?:(.*)\.)?([^.]+)$/;
875 $const{$1||''}{$2} = $val;
878 $this_as =~ /^(?:(.*)\.)?([^.]+)$/;
879 $const{$1||''}{$2} = $val;
883 my $alias = $self->{attrs}{alias};
884 my $info = [ {}, {} ];
885 foreach my $key (keys %const) {
886 if (length $key && $key ne $alias) {
888 my @parts = split(/\./, $key);
889 foreach my $p (@parts) {
890 $target = $target->[1]->{$p} ||= [];
892 $target->[0] = $const{$key};
894 $info->[0] = $const{$key};
899 if (defined $prefix) {
901 m/^\Q${prefix}.\E(.+)$/ ? ($1) : ()
902 } keys %{$self->{_attrs}{collapse}}
904 @collapse = keys %{$self->{_attrs}{collapse}};
908 my ($c) = sort { length $a <=> length $b } @collapse;
910 foreach my $p (split(/\./, $c)) {
911 $target = $target->[1]->{$p} ||= [];
913 my $c_prefix = (defined($prefix) ? "${prefix}.${c}" : $c);
914 my @co_key = @{$self->{_attrs}{collapse}{$c_prefix}};
915 my $tree = $self->_collapse_result($as, $row, $c_prefix);
916 my %co_check = map { ($_, $tree->[0]->{$_}); } @co_key;
922 !defined($tree->[0]->{$_}) || $co_check{$_} ne $tree->[0]->{$_}
927 last unless (@raw = $self->cursor->next);
928 $row = $self->{stashed_row} = \@raw;
929 $tree = $self->_collapse_result($as, $row, $c_prefix);
931 @$target = (@final ? @final : [ {}, {} ]);
932 # single empty result to indicate an empty prefetched has_many
935 #print "final info: " . Dumper($info);
943 =item Arguments: $result_source?
945 =item Return Value: $result_source
949 An accessor for the primary ResultSource object from which this ResultSet
959 =item Arguments: $cond, \%attrs??
961 =item Return Value: $count
965 Performs an SQL C<COUNT> with the same query as the resultset was built
966 with to find the number of elements. If passed arguments, does a search
967 on the resultset and counts the results of that.
969 Note: When using C<count> with C<group_by>, L<DBIX::Class> emulates C<GROUP BY>
970 using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do
971 not support C<DISTINCT> with multiple columns. If you are using such a
972 database, you should only use columns from the main table in your C<group_by>
979 return $self->search(@_)->count if @_ and defined $_[0];
980 return scalar @{ $self->get_cache } if $self->get_cache;
981 my $count = $self->_count;
982 return 0 unless $count;
984 $count -= $self->{attrs}{offset} if $self->{attrs}{offset};
985 $count = $self->{attrs}{rows} if
986 $self->{attrs}{rows} and $self->{attrs}{rows} < $count;
990 sub _count { # Separated out so pager can get the full count
992 my $select = { count => '*' };
994 my $attrs = { %{$self->_resolved_attrs} };
995 if (my $group_by = delete $attrs->{group_by}) {
996 delete $attrs->{having};
997 my @distinct = (ref $group_by ? @$group_by : ($group_by));
998 # todo: try CONCAT for multi-column pk
999 my @pk = $self->result_source->primary_columns;
1001 my $alias = $attrs->{_orig_alias};
1002 foreach my $column (@distinct) {
1003 if ($column =~ qr/^(?:\Q${alias}.\E)?$pk[0]$/) {
1004 @distinct = ($column);
1010 $select = { count => { distinct => \@distinct } };
1013 $attrs->{select} = $select;
1014 $attrs->{as} = [qw/count/];
1016 # offset, order by and page are not needed to count. record_filter is cdbi
1017 delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/;
1018 my $tmp_rs = (ref $self)->new($self->result_source, $attrs);
1019 $tmp_rs->{_parent_source} = $self->{_parent_source} if $self->{_parent_source};
1020 #XXX - hack to pass through parent of related resultsets
1022 my ($count) = $tmp_rs->cursor->next;
1026 =head2 count_literal
1030 =item Arguments: $sql_fragment, @bind_values
1032 =item Return Value: $count
1036 Counts the results in a literal query. Equivalent to calling L</search_literal>
1037 with the passed arguments, then L</count>.
1041 sub count_literal { shift->search_literal(@_)->count; }
1047 =item Arguments: none
1049 =item Return Value: @objects
1053 Returns all elements in the resultset. Called implicitly if the resultset
1054 is returned in list context.
1060 return @{ $self->get_cache } if $self->get_cache;
1064 # TODO: don't call resolve here
1065 if (keys %{$self->_resolved_attrs->{collapse}}) {
1066 # if ($self->{attrs}{prefetch}) {
1067 # Using $self->cursor->all is really just an optimisation.
1068 # If we're collapsing has_many prefetches it probably makes
1069 # very little difference, and this is cleaner than hacking
1070 # _construct_object to survive the approach
1071 my @row = $self->cursor->next;
1073 push(@obj, $self->_construct_object(@row));
1074 @row = (exists $self->{stashed_row}
1075 ? @{delete $self->{stashed_row}}
1076 : $self->cursor->next);
1079 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1082 $self->set_cache(\@obj) if $self->{attrs}{cache};
1090 =item Arguments: none
1092 =item Return Value: $self
1096 Resets the resultset's cursor, so you can iterate through the elements again.
1102 delete $self->{_attrs} if exists $self->{_attrs};
1103 $self->{all_cache_position} = 0;
1104 $self->cursor->reset;
1112 =item Arguments: none
1114 =item Return Value: $object?
1118 Resets the resultset and returns an object for the first result (if the
1119 resultset returns anything).
1124 return $_[0]->reset->next;
1127 # _cond_for_update_delete
1129 # update/delete require the condition to be modified to handle
1130 # the differing SQL syntax available. This transforms the $self->{cond}
1131 # appropriately, returning the new condition.
1133 sub _cond_for_update_delete {
1137 # No-op. No condition, we're updating/deleting everything
1138 return $cond unless ref $self->{cond};
1140 if (ref $self->{cond} eq 'ARRAY') {
1144 foreach my $key (keys %{$_}) {
1146 $hash{$1} = $_->{$key};
1152 elsif (ref $self->{cond} eq 'HASH') {
1153 if ((keys %{$self->{cond}})[0] eq '-and') {
1156 my @cond = @{$self->{cond}{-and}};
1157 for (my $i = 0; $i < @cond; $i++) {
1158 my $entry = $cond[$i];
1161 if (ref $entry eq 'HASH') {
1162 foreach my $key (keys %{$entry}) {
1164 $hash{$1} = $entry->{$key};
1168 $entry =~ /([^.]+)$/;
1169 $hash{$1} = $cond[++$i];
1172 push @{$cond->{-and}}, \%hash;
1176 foreach my $key (keys %{$self->{cond}}) {
1178 $cond->{$1} = $self->{cond}{$key};
1183 $self->throw_exception(
1184 "Can't update/delete on resultset with condition unless hash or array"
1196 =item Arguments: \%values
1198 =item Return Value: $storage_rv
1202 Sets the specified columns in the resultset to the supplied values in a
1203 single query. Return value will be true if the update succeeded or false
1204 if no records were updated; exact type of success value is storage-dependent.
1209 my ($self, $values) = @_;
1210 $self->throw_exception("Values for update must be a hash")
1211 unless ref $values eq 'HASH';
1213 my $cond = $self->_cond_for_update_delete;
1215 return $self->result_source->storage->update(
1216 $self->result_source->from, $values, $cond
1224 =item Arguments: \%values
1226 =item Return Value: 1
1230 Fetches all objects and updates them one at a time. Note that C<update_all>
1231 will run DBIC cascade triggers, while L</update> will not.
1236 my ($self, $values) = @_;
1237 $self->throw_exception("Values for update must be a hash")
1238 unless ref $values eq 'HASH';
1239 foreach my $obj ($self->all) {
1240 $obj->set_columns($values)->update;
1249 =item Arguments: none
1251 =item Return Value: 1
1255 Deletes the contents of the resultset from its result source. Note that this
1256 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1264 my $cond = $self->_cond_for_update_delete;
1266 $self->result_source->storage->delete($self->result_source->from, $cond);
1274 =item Arguments: none
1276 =item Return Value: 1
1280 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1281 will run DBIC cascade triggers, while L</delete> will not.
1287 $_->delete for $self->all;
1295 =item Arguments: none
1297 =item Return Value: $pager
1301 Return Value a L<Data::Page> object for the current resultset. Only makes
1302 sense for queries with a C<page> attribute.
1308 my $attrs = $self->{attrs};
1309 $self->throw_exception("Can't create pager for non-paged rs")
1310 unless $self->{attrs}{page};
1311 $attrs->{rows} ||= 10;
1312 return $self->{pager} ||= Data::Page->new(
1313 $self->_count, $attrs->{rows}, $self->{attrs}{page});
1320 =item Arguments: $page_number
1322 =item Return Value: $rs
1326 Returns a resultset for the $page_number page of the resultset on which page
1327 is called, where each page contains a number of rows equal to the 'rows'
1328 attribute set on the resultset (10 by default).
1333 my ($self, $page) = @_;
1334 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1341 =item Arguments: \%vals
1343 =item Return Value: $object
1347 Creates an object in the resultset's result class and returns it.
1352 my ($self, $values) = @_;
1353 $self->throw_exception( "new_result needs a hash" )
1354 unless (ref $values eq 'HASH');
1355 $self->throw_exception(
1356 "Can't abstract implicit construct, condition not a hash"
1357 ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
1359 my $alias = $self->{attrs}{_orig_alias};
1360 foreach my $key (keys %{$self->{cond}||{}}) {
1361 $new{$1} = $self->{cond}{$key} if ($key =~ m/^(?:\Q${alias}.\E)?([^.]+)$/);
1363 my $obj = $self->result_class->new(\%new);
1364 $obj->result_source($self->result_source) if $obj->can('result_source');
1372 =item Arguments: \%vals, \%attrs?
1374 =item Return Value: $object
1378 Find an existing record from this resultset. If none exists, instantiate a new
1379 result object and return it. The object will not be saved into your storage
1380 until you call L<DBIx::Class::Row/insert> on it.
1382 If you want objects to be saved immediately, use L</find_or_create> instead.
1388 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1389 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1390 my $exists = $self->find($hash, $attrs);
1391 return defined $exists ? $exists : $self->new_result($hash);
1398 =item Arguments: \%vals
1400 =item Return Value: $object
1404 Inserts a record into the resultset and returns the object representing it.
1406 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
1411 my ($self, $attrs) = @_;
1412 $self->throw_exception( "create needs a hashref" )
1413 unless ref $attrs eq 'HASH';
1414 return $self->new_result($attrs)->insert;
1417 =head2 find_or_create
1421 =item Arguments: \%vals, \%attrs?
1423 =item Return Value: $object
1427 $class->find_or_create({ key => $val, ... });
1429 Tries to find a record based on its primary key or unique constraint; if none
1430 is found, creates one and returns that instead.
1432 my $cd = $schema->resultset('CD')->find_or_create({
1434 artist => 'Massive Attack',
1435 title => 'Mezzanine',
1439 Also takes an optional C<key> attribute, to search by a specific key or unique
1440 constraint. For example:
1442 my $cd = $schema->resultset('CD')->find_or_create(
1444 artist => 'Massive Attack',
1445 title => 'Mezzanine',
1447 { key => 'cd_artist_title' }
1450 See also L</find> and L</update_or_create>. For information on how to declare
1451 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1455 sub find_or_create {
1457 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1458 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1459 my $exists = $self->find($hash, $attrs);
1460 return defined $exists ? $exists : $self->create($hash);
1463 =head2 update_or_create
1467 =item Arguments: \%col_values, { key => $unique_constraint }?
1469 =item Return Value: $object
1473 $class->update_or_create({ col => $val, ... });
1475 First, searches for an existing row matching one of the unique constraints
1476 (including the primary key) on the source of this resultset. If a row is
1477 found, updates it with the other given column values. Otherwise, creates a new
1480 Takes an optional C<key> attribute to search on a specific unique constraint.
1483 # In your application
1484 my $cd = $schema->resultset('CD')->update_or_create(
1486 artist => 'Massive Attack',
1487 title => 'Mezzanine',
1490 { key => 'cd_artist_title' }
1493 If no C<key> is specified, it searches on all unique constraints defined on the
1494 source, including the primary key.
1496 If the C<key> is specified as C<primary>, it searches only on the primary key.
1498 See also L</find> and L</find_or_create>. For information on how to declare
1499 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1503 sub update_or_create {
1505 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1506 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
1508 my $row = $self->find($cond);
1510 $row->update($cond);
1514 return $self->create($cond);
1521 =item Arguments: none
1523 =item Return Value: \@cache_objects?
1527 Gets the contents of the cache for the resultset, if the cache is set.
1539 =item Arguments: \@cache_objects
1541 =item Return Value: \@cache_objects
1545 Sets the contents of the cache for the resultset. Expects an arrayref
1546 of objects of the same class as those produced by the resultset. Note that
1547 if the cache is set the resultset will return the cached objects rather
1548 than re-querying the database even if the cache attr is not set.
1553 my ( $self, $data ) = @_;
1554 $self->throw_exception("set_cache requires an arrayref")
1555 if defined($data) && (ref $data ne 'ARRAY');
1556 $self->{all_cache} = $data;
1563 =item Arguments: none
1565 =item Return Value: []
1569 Clears the cache for the resultset.
1574 shift->set_cache(undef);
1577 =head2 related_resultset
1581 =item Arguments: $relationship_name
1583 =item Return Value: $resultset
1587 Returns a related resultset for the supplied relationship name.
1589 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
1593 sub related_resultset {
1594 my ($self, $rel) = @_;
1596 $self->{related_resultsets} ||= {};
1597 return $self->{related_resultsets}{$rel} ||= do {
1598 my $rel_obj = $self->result_source->relationship_info($rel);
1600 $self->throw_exception(
1601 "search_related: result source '" . $self->result_source->name .
1602 "' has no such relationship $rel")
1605 my @live_join_stack = @{$self->{attrs}{_live_join_stack}||[]};
1607 # XXX mst: I'm sure this is wrong, somehow
1608 # something with complex joins early on could die on search_rel
1609 # followed by a prefetch. I think. need a test case.
1611 my $join_count = scalar(grep { $_ eq $rel } @live_join_stack);
1612 my $alias = $join_count ? join('_', $rel, $join_count+1) : $rel;
1614 push(@live_join_stack, $rel);
1616 my $rs = $self->result_source->schema->resultset($rel_obj->{class})->search(
1621 _live_join_stack => \@live_join_stack,
1622 _parent_attrs => $self->{attrs}}
1625 # keep reference of the original resultset
1626 $rs->{_parent_source} = $self->{_parent_source} || $self->result_source;
1632 =head2 throw_exception
1634 See L<DBIx::Class::Schema/throw_exception> for details.
1638 sub throw_exception {
1640 $self->result_source->schema->throw_exception(@_);
1643 # XXX: FIXME: Attributes docs need clearing up
1647 The resultset takes various attributes that modify its behavior. Here's an
1654 =item Value: ($order_by | \@order_by)
1658 Which column(s) to order the results by. This is currently passed
1659 through directly to SQL, so you can give e.g. C<year DESC> for a
1660 descending order on the column `year'.
1662 Please note that if you have quoting enabled (see
1663 L<DBIx::Class::Storage/quote_char>) you will need to do C<\'year DESC' > to
1664 specify an order. (The scalar ref causes it to be passed as raw sql to the DB,
1665 so you will need to manually quote things as appropriate.)
1671 =item Value: \@columns
1675 Shortcut to request a particular set of columns to be retrieved. Adds
1676 C<me.> onto the start of any column without a C<.> in it and sets C<select>
1677 from that, then auto-populates C<as> from C<select> as normal. (You may also
1678 use the C<cols> attribute, as in earlier versions of DBIC.)
1680 =head2 include_columns
1684 =item Value: \@columns
1688 Shortcut to include additional columns in the returned results - for example
1690 $schema->resultset('CD')->search(undef, {
1691 include_columns => ['artist.name'],
1695 would return all CDs and include a 'name' column to the information
1696 passed to object inflation
1702 =item Value: \@select_columns
1706 Indicates which columns should be selected from the storage. You can use
1707 column names, or in the case of RDBMS back ends, function or stored procedure
1710 $rs = $schema->resultset('Employee')->search(undef, {
1713 { count => 'employeeid' },
1718 When you use function/stored procedure names and do not supply an C<as>
1719 attribute, the column names returned are storage-dependent. E.g. MySQL would
1720 return a column named C<count(employeeid)> in the above example.
1726 Indicates additional columns to be selected from storage. Works the same as
1727 L<select> but adds columns to the selection.
1735 Indicates additional column names for those added via L<+select>.
1743 =item Value: \@inflation_names
1747 Indicates column names for object inflation. This is used in conjunction with
1748 C<select>, usually when C<select> contains one or more function or stored
1751 $rs = $schema->resultset('Employee')->search(undef, {
1754 { count => 'employeeid' }
1756 as => ['name', 'employee_count'],
1759 my $employee = $rs->first(); # get the first Employee
1761 If the object against which the search is performed already has an accessor
1762 matching a column name specified in C<as>, the value can be retrieved using
1763 the accessor as normal:
1765 my $name = $employee->name();
1767 If on the other hand an accessor does not exist in the object, you need to
1768 use C<get_column> instead:
1770 my $employee_count = $employee->get_column('employee_count');
1772 You can create your own accessors if required - see
1773 L<DBIx::Class::Manual::Cookbook> for details.
1775 Please note: This will NOT insert an C<AS employee_count> into the SQL statement
1776 produced, it is used for internal access only. Thus attempting to use the accessor
1777 in an C<order_by> clause or similar will fail misrably.
1783 =item Value: ($rel_name | \@rel_names | \%rel_names)
1787 Contains a list of relationships that should be joined for this query. For
1790 # Get CDs by Nine Inch Nails
1791 my $rs = $schema->resultset('CD')->search(
1792 { 'artist.name' => 'Nine Inch Nails' },
1793 { join => 'artist' }
1796 Can also contain a hash reference to refer to the other relation's relations.
1799 package MyApp::Schema::Track;
1800 use base qw/DBIx::Class/;
1801 __PACKAGE__->table('track');
1802 __PACKAGE__->add_columns(qw/trackid cd position title/);
1803 __PACKAGE__->set_primary_key('trackid');
1804 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
1807 # In your application
1808 my $rs = $schema->resultset('Artist')->search(
1809 { 'track.title' => 'Teardrop' },
1811 join => { cd => 'track' },
1812 order_by => 'artist.name',
1816 If the same join is supplied twice, it will be aliased to <rel>_2 (and
1817 similarly for a third time). For e.g.
1819 my $rs = $schema->resultset('Artist')->search({
1820 'cds.title' => 'Down to Earth',
1821 'cds_2.title' => 'Popular',
1823 join => [ qw/cds cds/ ],
1826 will return a set of all artists that have both a cd with title 'Down
1827 to Earth' and a cd with title 'Popular'.
1829 If you want to fetch related objects from other tables as well, see C<prefetch>
1836 =item Value: ($rel_name | \@rel_names | \%rel_names)
1840 Contains one or more relationships that should be fetched along with the main
1841 query (when they are accessed afterwards they will have already been
1842 "prefetched"). This is useful for when you know you will need the related
1843 objects, because it saves at least one query:
1845 my $rs = $schema->resultset('Tag')->search(
1854 The initial search results in SQL like the following:
1856 SELECT tag.*, cd.*, artist.* FROM tag
1857 JOIN cd ON tag.cd = cd.cdid
1858 JOIN artist ON cd.artist = artist.artistid
1860 L<DBIx::Class> has no need to go back to the database when we access the
1861 C<cd> or C<artist> relationships, which saves us two SQL statements in this
1864 Simple prefetches will be joined automatically, so there is no need
1865 for a C<join> attribute in the above search. If you're prefetching to
1866 depth (e.g. { cd => { artist => 'label' } or similar), you'll need to
1867 specify the join as well.
1869 C<prefetch> can be used with the following relationship types: C<belongs_to>,
1870 C<has_one> (or if you're using C<add_relationship>, any relationship declared
1871 with an accessor type of 'single' or 'filter').
1881 Makes the resultset paged and specifies the page to retrieve. Effectively
1882 identical to creating a non-pages resultset and then calling ->page($page)
1885 If L<rows> attribute is not specified it defualts to 10 rows per page.
1895 Specifes the maximum number of rows for direct retrieval or the number of
1896 rows per page if the page attribute or method is used.
1902 =item Value: $offset
1906 Specifies the (zero-based) row number for the first row to be returned, or the
1907 of the first row of the first page if paging is used.
1913 =item Value: \@columns
1917 A arrayref of columns to group by. Can include columns of joined tables.
1919 group_by => [qw/ column1 column2 ... /]
1925 =item Value: $condition
1929 HAVING is a select statement attribute that is applied between GROUP BY and
1930 ORDER BY. It is applied to the after the grouping calculations have been
1933 having => { 'count(employee)' => { '>=', 100 } }
1939 =item Value: (0 | 1)
1943 Set to 1 to group by all columns.
1949 Adds to the WHERE clause.
1951 # only return rows WHERE deleted IS NULL for all searches
1952 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
1954 Can be overridden by passing C<{ where => undef }> as an attribute
1961 Set to 1 to cache search results. This prevents extra SQL queries if you
1962 revisit rows in your ResultSet:
1964 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
1966 while( my $artist = $resultset->next ) {
1970 $rs->first; # without cache, this would issue a query
1972 By default, searches are not cached.
1974 For more examples of using these attributes, see
1975 L<DBIx::Class::Manual::Cookbook>.
1981 =item Value: \@from_clause
1985 The C<from> attribute gives you manual control over the C<FROM> clause of SQL
1986 statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
1989 NOTE: Use this on your own risk. This allows you to shoot off your foot!
1991 C<join> will usually do what you need and it is strongly recommended that you
1992 avoid using C<from> unless you cannot achieve the desired result using C<join>.
1993 And we really do mean "cannot", not just tried and failed. Attempting to use
1994 this because you're having problems with C<join> is like trying to use x86
1995 ASM because you've got a syntax error in your C. Trust us on this.
1997 Now, if you're still really, really sure you need to use this (and if you're
1998 not 100% sure, ask the mailing list first), here's an explanation of how this
2001 The syntax is as follows -
2004 { <alias1> => <table1> },
2006 { <alias2> => <table2>, -join_type => 'inner|left|right' },
2007 [], # nested JOIN (optional)
2008 { <table1.column1> => <table2.column2>, ... (more conditions) },
2010 # More of the above [ ] may follow for additional joins
2017 ON <table1.column1> = <table2.column2>
2018 <more joins may follow>
2020 An easy way to follow the examples below is to remember the following:
2022 Anything inside "[]" is a JOIN
2023 Anything inside "{}" is a condition for the enclosing JOIN
2025 The following examples utilize a "person" table in a family tree application.
2026 In order to express parent->child relationships, this table is self-joined:
2028 # Person->belongs_to('father' => 'Person');
2029 # Person->belongs_to('mother' => 'Person');
2031 C<from> can be used to nest joins. Here we return all children with a father,
2032 then search against all mothers of those children:
2034 $rs = $schema->resultset('Person')->search(
2037 alias => 'mother', # alias columns in accordance with "from"
2039 { mother => 'person' },
2042 { child => 'person' },
2044 { father => 'person' },
2045 { 'father.person_id' => 'child.father_id' }
2048 { 'mother.person_id' => 'child.mother_id' }
2055 # SELECT mother.* FROM person mother
2058 # JOIN person father
2059 # ON ( father.person_id = child.father_id )
2061 # ON ( mother.person_id = child.mother_id )
2063 The type of any join can be controlled manually. To search against only people
2064 with a father in the person table, we could explicitly use C<INNER JOIN>:
2066 $rs = $schema->resultset('Person')->search(
2069 alias => 'child', # alias columns in accordance with "from"
2071 { child => 'person' },
2073 { father => 'person', -join_type => 'inner' },
2074 { 'father.id' => 'child.father_id' }
2081 # SELECT child.* FROM person child
2082 # INNER JOIN person father ON child.father_id = father.id