1 package DBIx::Class::ResultSet;
9 use Carp::Clan qw/^DBIx::Class/;
12 use DBIx::Class::ResultSetColumn;
13 use base qw/DBIx::Class/;
15 __PACKAGE__->load_components(qw/AccessorGroup/);
16 __PACKAGE__->mk_group_accessors('simple' => qw/result_source result_class/);
20 DBIx::Class::ResultSet - Responsible for fetching and creating resultset.
24 my $rs = $schema->resultset('User')->search(registered => 1);
25 my @rows = $schema->resultset('CD')->search(year => 2005);
29 The resultset is also known as an iterator. It is responsible for handling
30 queries that may return an arbitrary number of rows, e.g. via L</search>
31 or a C<has_many> relationship.
33 In the examples below, the following table classes are used:
35 package MyApp::Schema::Artist;
36 use base qw/DBIx::Class/;
37 __PACKAGE__->load_components(qw/Core/);
38 __PACKAGE__->table('artist');
39 __PACKAGE__->add_columns(qw/artistid name/);
40 __PACKAGE__->set_primary_key('artistid');
41 __PACKAGE__->has_many(cds => 'MyApp::Schema::CD');
44 package MyApp::Schema::CD;
45 use base qw/DBIx::Class/;
46 __PACKAGE__->load_components(qw/Core/);
47 __PACKAGE__->table('cd');
48 __PACKAGE__->add_columns(qw/cdid artist title year/);
49 __PACKAGE__->set_primary_key('cdid');
50 __PACKAGE__->belongs_to(artist => 'MyApp::Schema::Artist');
59 =item Arguments: $source, \%$attrs
61 =item Return Value: $rs
65 The resultset constructor. Takes a source object (usually a
66 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
67 L</ATTRIBUTES> below). Does not perform any queries -- these are
68 executed as needed by the other methods.
70 Generally you won't need to construct a resultset manually. You'll
71 automatically get one from e.g. a L</search> called in scalar context:
73 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
75 IMPORTANT: If called on an object, proxies to new_result instead so
77 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
79 will return a CD object, not a ResultSet.
85 return $class->new_result(@_) if ref $class;
87 my ($source, $attrs) = @_;
91 $attrs->{rows} ||= 10;
92 $attrs->{offset} ||= 0;
93 $attrs->{offset} += ($attrs->{rows} * ($attrs->{page} - 1));
96 $attrs->{alias} ||= 'me';
99 result_source => $source,
100 result_class => $attrs->{result_class} || $source->result_class,
101 cond => $attrs->{where},
116 =item Arguments: $cond, \%attrs?
118 =item Return Value: $resultset (scalar context), @row_objs (list context)
122 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
123 my $new_rs = $cd_rs->search({ year => 2005 });
125 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
126 # year = 2005 OR year = 2004
128 If you need to pass in additional attributes but no additional condition,
129 call it as C<search(undef, \%attrs)>.
131 # "SELECT name, artistid FROM $artist_table"
132 my @all_artists = $schema->resultset('Artist')->search(undef, {
133 columns => [qw/name artistid/],
136 For a list of attributes that can be passed to C<search>, see L</ATTRIBUTES>. For more examples of using this function, see L<Searching|DBIx::Class::Manual::Cookbook/Searching>.
142 my $rs = $self->search_rs( @_ );
143 return (wantarray ? $rs->all : $rs);
150 =item Arguments: $cond, \%attrs?
152 =item Return Value: $resultset
156 This method does the same exact thing as search() except it will
157 always return a resultset, even in list context.
166 unless (@_) { # no search, effectively just a clone
167 $rows = $self->get_cache;
171 $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
172 my $our_attrs = { %{$self->{attrs}} };
173 my $having = delete $our_attrs->{having};
174 my $where = delete $our_attrs->{where};
176 my $new_attrs = { %{$our_attrs}, %{$attrs} };
178 # merge new attrs into inherited
179 foreach my $key (qw/join prefetch/) {
180 next unless exists $attrs->{$key};
181 $new_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key});
186 (@_ == 1 || ref $_[0] eq "HASH")
188 (ref $_[0] eq 'HASH')
190 (keys %{ $_[0] } > 0)
198 ? $self->throw_exception("Odd number of arguments to search")
205 if (defined $where) {
206 $new_attrs->{where} = (
207 defined $new_attrs->{where}
210 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
211 } $where, $new_attrs->{where}
218 $new_attrs->{where} = (
219 defined $new_attrs->{where}
222 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
223 } $cond, $new_attrs->{where}
229 if (defined $having) {
230 $new_attrs->{having} = (
231 defined $new_attrs->{having}
234 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
235 } $having, $new_attrs->{having}
241 my $rs = (ref $self)->new($self->result_source, $new_attrs);
243 $rs->set_cache($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 If your table does not have a primary key, you B<must> provide a value for the
311 C<key> attribute matching one of the unique constraints on the source.
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 is defined or unique constraint is specified"
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 # Build the final query: Default to the disjunction of the unique queries,
349 # but allow the input query in case the ResultSet defines the query or the
350 # user is abusing find
351 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
352 my $query = @unique_queries
353 ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
354 : $self->_add_alias($input_query, $alias);
358 my $rs = $self->search($query, $attrs);
359 return keys %{$rs->_resolved_attrs->{collapse}} ? $rs->next : $rs->single;
362 return keys %{$self->_resolved_attrs->{collapse}}
363 ? $self->search($query)->next
364 : $self->single($query);
370 # Add the specified alias to the specified query hash. A copy is made so the
371 # original query is not modified.
374 my ($self, $query, $alias) = @_;
376 my %aliased = %$query;
377 foreach my $col (grep { ! m/\./ } keys %aliased) {
378 $aliased{"$alias.$col"} = delete $aliased{$col};
386 # Build a list of queries which satisfy unique constraints.
388 sub _unique_queries {
389 my ($self, $query, $attrs) = @_;
391 my @constraint_names = exists $attrs->{key}
393 : $self->result_source->unique_constraint_names;
396 foreach my $name (@constraint_names) {
397 my @unique_cols = $self->result_source->unique_constraint_columns($name);
398 my $unique_query = $self->_build_unique_query($query, \@unique_cols);
400 my $num_query = scalar keys %$unique_query;
401 next unless $num_query;
403 # XXX: Assuming quite a bit about $self->{attrs}{where}
404 my $num_cols = scalar @unique_cols;
405 my $num_where = exists $self->{attrs}{where}
406 ? scalar keys %{ $self->{attrs}{where} }
408 push @unique_queries, $unique_query
409 if $num_query + $num_where == $num_cols;
412 return @unique_queries;
415 # _build_unique_query
417 # Constrain the specified query hash based on the specified column names.
419 sub _build_unique_query {
420 my ($self, $query, $unique_cols) = @_;
423 map { $_ => $query->{$_} }
424 grep { exists $query->{$_} }
429 =head2 search_related
433 =item Arguments: $rel, $cond, \%attrs?
435 =item Return Value: $new_resultset
439 $new_rs = $cd_rs->search_related('artist', {
443 Searches the specified relationship, optionally specifying a condition and
444 attributes for matching records. See L</ATTRIBUTES> for more information.
449 return shift->related_resultset(shift)->search(@_);
456 =item Arguments: none
458 =item Return Value: $cursor
462 Returns a storage-driven cursor to the given resultset. See
463 L<DBIx::Class::Cursor> for more information.
470 my $attrs = { %{$self->_resolved_attrs} };
471 return $self->{cursor}
472 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
473 $attrs->{where},$attrs);
480 =item Arguments: $cond?
482 =item Return Value: $row_object?
486 my $cd = $schema->resultset('CD')->single({ year => 2001 });
488 Inflates the first result without creating a cursor if the resultset has
489 any records in it; if not returns nothing. Used by L</find> as an optimisation.
491 Can optionally take an additional condition *only* - this is a fast-code-path
492 method; if you need to add extra joins or similar call ->search and then
493 ->single without a condition on the $rs returned from that.
498 my ($self, $where) = @_;
499 my $attrs = { %{$self->_resolved_attrs} };
501 if (defined $attrs->{where}) {
504 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
505 $where, delete $attrs->{where} ]
508 $attrs->{where} = $where;
512 # XXX: Disabled since it doesn't infer uniqueness in all cases
513 # unless ($self->_is_unique_query($attrs->{where})) {
514 # carp "Query not guaranteed to return a single row"
515 # . "; please declare your unique constraints or use search instead";
518 my @data = $self->result_source->storage->select_single(
519 $attrs->{from}, $attrs->{select},
520 $attrs->{where}, $attrs
523 return (@data ? $self->_construct_object(@data) : ());
528 # Try to determine if the specified query is guaranteed to be unique, based on
529 # the declared unique constraints.
531 sub _is_unique_query {
532 my ($self, $query) = @_;
534 my $collapsed = $self->_collapse_query($query);
535 my $alias = $self->{attrs}{alias};
537 foreach my $name ($self->result_source->unique_constraint_names) {
538 my @unique_cols = map {
540 } $self->result_source->unique_constraint_columns($name);
542 # Count the values for each unique column
543 my %seen = map { $_ => 0 } @unique_cols;
545 foreach my $key (keys %$collapsed) {
546 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
547 next unless exists $seen{$aliased}; # Additional constraints are okay
548 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
551 # If we get 0 or more than 1 value for a column, it's not necessarily unique
552 return 1 unless grep { $_ != 1 } values %seen;
560 # Recursively collapse the query, accumulating values for each column.
562 sub _collapse_query {
563 my ($self, $query, $collapsed) = @_;
567 if (ref $query eq 'ARRAY') {
568 foreach my $subquery (@$query) {
569 next unless ref $subquery; # -or
570 # warn "ARRAY: " . Dumper $subquery;
571 $collapsed = $self->_collapse_query($subquery, $collapsed);
574 elsif (ref $query eq 'HASH') {
575 if (keys %$query and (keys %$query)[0] eq '-and') {
576 foreach my $subquery (@{$query->{-and}}) {
577 # warn "HASH: " . Dumper $subquery;
578 $collapsed = $self->_collapse_query($subquery, $collapsed);
582 # warn "LEAF: " . Dumper $query;
583 foreach my $col (keys %$query) {
584 my $value = $query->{$col};
585 $collapsed->{$col}{$value}++;
597 =item Arguments: $cond?
599 =item Return Value: $resultsetcolumn
603 my $max_length = $rs->get_column('length')->max;
605 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
610 my ($self, $column) = @_;
611 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
619 =item Arguments: $cond, \%attrs?
621 =item Return Value: $resultset (scalar context), @row_objs (list context)
625 # WHERE title LIKE '%blue%'
626 $cd_rs = $rs->search_like({ title => '%blue%'});
628 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
629 that this is simply a convenience method. You most likely want to use
630 L</search> with specific operators.
632 For more information, see L<DBIx::Class::Manual::Cookbook>.
638 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
639 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
640 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
641 return $class->search($query, { %$attrs });
648 =item Arguments: $first, $last
650 =item Return Value: $resultset (scalar context), @row_objs (list context)
654 Returns a resultset or object list representing a subset of elements from the
655 resultset slice is called on. Indexes are from 0, i.e., to get the first
658 my ($one, $two, $three) = $rs->slice(0, 2);
663 my ($self, $min, $max) = @_;
664 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
665 $attrs->{offset} = $self->{attrs}{offset} || 0;
666 $attrs->{offset} += $min;
667 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
668 return $self->search(undef(), $attrs);
669 #my $slice = (ref $self)->new($self->result_source, $attrs);
670 #return (wantarray ? $slice->all : $slice);
677 =item Arguments: none
679 =item Return Value: $result?
683 Returns the next element in the resultset (C<undef> is there is none).
685 Can be used to efficiently iterate over records in the resultset:
687 my $rs = $schema->resultset('CD')->search;
688 while (my $cd = $rs->next) {
692 Note that you need to store the resultset object, and call C<next> on it.
693 Calling C<< resultset('Table')->next >> repeatedly will always return the
694 first record from the resultset.
700 if (my $cache = $self->get_cache) {
701 $self->{all_cache_position} ||= 0;
702 return $cache->[$self->{all_cache_position}++];
704 if ($self->{attrs}{cache}) {
705 $self->{all_cache_position} = 1;
706 return ($self->all)[0];
709 exists $self->{stashed_row}
710 ? @{delete $self->{stashed_row}}
711 : $self->cursor->next
713 return unless (@row);
714 return $self->_construct_object(@row);
717 sub _construct_object {
718 my ($self, @row) = @_;
719 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row);
720 my $new = $self->result_class->inflate_result($self->result_source, @$info);
721 $new = $self->{_attrs}{record_filter}->($new)
722 if exists $self->{_attrs}{record_filter};
726 sub _collapse_result {
727 my ($self, $as, $row, $prefix) = @_;
732 foreach my $this_as (@$as) {
733 my $val = shift @copy;
734 if (defined $prefix) {
735 if ($this_as =~ m/^\Q${prefix}.\E(.+)$/) {
737 $remain =~ /^(?:(.*)\.)?([^.]+)$/;
738 $const{$1||''}{$2} = $val;
741 $this_as =~ /^(?:(.*)\.)?([^.]+)$/;
742 $const{$1||''}{$2} = $val;
746 my $alias = $self->{attrs}{alias};
747 my $info = [ {}, {} ];
748 foreach my $key (keys %const) {
749 if (length $key && $key ne $alias) {
751 my @parts = split(/\./, $key);
752 foreach my $p (@parts) {
753 $target = $target->[1]->{$p} ||= [];
755 $target->[0] = $const{$key};
757 $info->[0] = $const{$key};
762 if (defined $prefix) {
764 m/^\Q${prefix}.\E(.+)$/ ? ($1) : ()
765 } keys %{$self->{_attrs}{collapse}}
767 @collapse = keys %{$self->{_attrs}{collapse}};
771 my ($c) = sort { length $a <=> length $b } @collapse;
773 foreach my $p (split(/\./, $c)) {
774 $target = $target->[1]->{$p} ||= [];
776 my $c_prefix = (defined($prefix) ? "${prefix}.${c}" : $c);
777 my @co_key = @{$self->{_attrs}{collapse}{$c_prefix}};
778 my $tree = $self->_collapse_result($as, $row, $c_prefix);
779 my %co_check = map { ($_, $tree->[0]->{$_}); } @co_key;
785 !defined($tree->[0]->{$_}) || $co_check{$_} ne $tree->[0]->{$_}
790 last unless (@raw = $self->cursor->next);
791 $row = $self->{stashed_row} = \@raw;
792 $tree = $self->_collapse_result($as, $row, $c_prefix);
794 @$target = (@final ? @final : [ {}, {} ]);
795 # single empty result to indicate an empty prefetched has_many
798 #print "final info: " . Dumper($info);
806 =item Arguments: $result_source?
808 =item Return Value: $result_source
812 An accessor for the primary ResultSource object from which this ResultSet
819 =item Arguments: $result_class?
821 =item Return Value: $result_class
825 An accessor for the class to use when creating row objects. Defaults to
826 C<< result_source->result_class >> - which in most cases is the name of the
827 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
836 =item Arguments: $cond, \%attrs??
838 =item Return Value: $count
842 Performs an SQL C<COUNT> with the same query as the resultset was built
843 with to find the number of elements. If passed arguments, does a search
844 on the resultset and counts the results of that.
846 Note: When using C<count> with C<group_by>, L<DBIX::Class> emulates C<GROUP BY>
847 using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do
848 not support C<DISTINCT> with multiple columns. If you are using such a
849 database, you should only use columns from the main table in your C<group_by>
856 return $self->search(@_)->count if @_ and defined $_[0];
857 return scalar @{ $self->get_cache } if $self->get_cache;
858 my $count = $self->_count;
859 return 0 unless $count;
861 $count -= $self->{attrs}{offset} if $self->{attrs}{offset};
862 $count = $self->{attrs}{rows} if
863 $self->{attrs}{rows} and $self->{attrs}{rows} < $count;
867 sub _count { # Separated out so pager can get the full count
869 my $select = { count => '*' };
871 my $attrs = { %{$self->_resolved_attrs} };
872 if (my $group_by = delete $attrs->{group_by}) {
873 delete $attrs->{having};
874 my @distinct = (ref $group_by ? @$group_by : ($group_by));
875 # todo: try CONCAT for multi-column pk
876 my @pk = $self->result_source->primary_columns;
878 my $alias = $attrs->{alias};
879 foreach my $column (@distinct) {
880 if ($column =~ qr/^(?:\Q${alias}.\E)?$pk[0]$/) {
881 @distinct = ($column);
887 $select = { count => { distinct => \@distinct } };
890 $attrs->{select} = $select;
891 $attrs->{as} = [qw/count/];
893 # offset, order by and page are not needed to count. record_filter is cdbi
894 delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/;
896 my $tmp_rs = (ref $self)->new($self->result_source, $attrs);
897 my ($count) = $tmp_rs->cursor->next;
905 =item Arguments: $sql_fragment, @bind_values
907 =item Return Value: $count
911 Counts the results in a literal query. Equivalent to calling L</search_literal>
912 with the passed arguments, then L</count>.
916 sub count_literal { shift->search_literal(@_)->count; }
922 =item Arguments: none
924 =item Return Value: @objects
928 Returns all elements in the resultset. Called implicitly if the resultset
929 is returned in list context.
935 return @{ $self->get_cache } if $self->get_cache;
939 # TODO: don't call resolve here
940 if (keys %{$self->_resolved_attrs->{collapse}}) {
941 # if ($self->{attrs}{prefetch}) {
942 # Using $self->cursor->all is really just an optimisation.
943 # If we're collapsing has_many prefetches it probably makes
944 # very little difference, and this is cleaner than hacking
945 # _construct_object to survive the approach
946 my @row = $self->cursor->next;
948 push(@obj, $self->_construct_object(@row));
949 @row = (exists $self->{stashed_row}
950 ? @{delete $self->{stashed_row}}
951 : $self->cursor->next);
954 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
957 $self->set_cache(\@obj) if $self->{attrs}{cache};
965 =item Arguments: none
967 =item Return Value: $self
971 Resets the resultset's cursor, so you can iterate through the elements again.
977 delete $self->{_attrs} if exists $self->{_attrs};
978 $self->{all_cache_position} = 0;
979 $self->cursor->reset;
987 =item Arguments: none
989 =item Return Value: $object?
993 Resets the resultset and returns an object for the first result (if the
994 resultset returns anything).
999 return $_[0]->reset->next;
1002 # _cond_for_update_delete
1004 # update/delete require the condition to be modified to handle
1005 # the differing SQL syntax available. This transforms the $self->{cond}
1006 # appropriately, returning the new condition.
1008 sub _cond_for_update_delete {
1009 my ($self, $full_cond) = @_;
1012 $full_cond ||= $self->{cond};
1013 # No-op. No condition, we're updating/deleting everything
1014 return $cond unless ref $full_cond;
1016 if (ref $full_cond eq 'ARRAY') {
1020 foreach my $key (keys %{$_}) {
1022 $hash{$1} = $_->{$key};
1028 elsif (ref $full_cond eq 'HASH') {
1029 if ((keys %{$full_cond})[0] eq '-and') {
1032 my @cond = @{$full_cond->{-and}};
1033 for (my $i = 0; $i < @cond; $i++) {
1034 my $entry = $cond[$i];
1037 if (ref $entry eq 'HASH') {
1038 $hash = $self->_cond_for_update_delete($entry);
1041 $entry =~ /([^.]+)$/;
1042 $hash->{$1} = $cond[++$i];
1045 push @{$cond->{-and}}, $hash;
1049 foreach my $key (keys %{$full_cond}) {
1051 $cond->{$1} = $full_cond->{$key};
1056 $self->throw_exception(
1057 "Can't update/delete on resultset with condition unless hash or array"
1069 =item Arguments: \%values
1071 =item Return Value: $storage_rv
1075 Sets the specified columns in the resultset to the supplied values in a
1076 single query. Return value will be true if the update succeeded or false
1077 if no records were updated; exact type of success value is storage-dependent.
1082 my ($self, $values) = @_;
1083 $self->throw_exception("Values for update must be a hash")
1084 unless ref $values eq 'HASH';
1086 my $cond = $self->_cond_for_update_delete;
1088 return $self->result_source->storage->update(
1089 $self->result_source->from, $values, $cond
1097 =item Arguments: \%values
1099 =item Return Value: 1
1103 Fetches all objects and updates them one at a time. Note that C<update_all>
1104 will run DBIC cascade triggers, while L</update> will not.
1109 my ($self, $values) = @_;
1110 $self->throw_exception("Values for update must be a hash")
1111 unless ref $values eq 'HASH';
1112 foreach my $obj ($self->all) {
1113 $obj->set_columns($values)->update;
1122 =item Arguments: none
1124 =item Return Value: 1
1128 Deletes the contents of the resultset from its result source. Note that this
1129 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1130 to run. See also L<DBIx::Class::Row/delete>.
1137 my $cond = $self->_cond_for_update_delete;
1139 $self->result_source->storage->delete($self->result_source->from, $cond);
1147 =item Arguments: none
1149 =item Return Value: 1
1153 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1154 will run DBIC cascade triggers, while L</delete> will not.
1160 $_->delete for $self->all;
1168 =item Arguments: none
1170 =item Return Value: $pager
1174 Return Value a L<Data::Page> object for the current resultset. Only makes
1175 sense for queries with a C<page> attribute.
1181 my $attrs = $self->{attrs};
1182 $self->throw_exception("Can't create pager for non-paged rs")
1183 unless $self->{attrs}{page};
1184 $attrs->{rows} ||= 10;
1185 return $self->{pager} ||= Data::Page->new(
1186 $self->_count, $attrs->{rows}, $self->{attrs}{page});
1193 =item Arguments: $page_number
1195 =item Return Value: $rs
1199 Returns a resultset for the $page_number page of the resultset on which page
1200 is called, where each page contains a number of rows equal to the 'rows'
1201 attribute set on the resultset (10 by default).
1206 my ($self, $page) = @_;
1207 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1214 =item Arguments: \%vals
1216 =item Return Value: $object
1220 Creates an object in the resultset's result class and returns it.
1225 my ($self, $values) = @_;
1226 $self->throw_exception( "new_result needs a hash" )
1227 unless (ref $values eq 'HASH');
1228 $self->throw_exception(
1229 "Can't abstract implicit construct, condition not a hash"
1230 ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
1232 my $alias = $self->{attrs}{alias};
1233 my $collapsed_cond = $self->{cond} ? $self->_collapse_cond($self->{cond}) : {};
1235 %{ $self->_remove_alias($values, $alias) },
1236 %{ $self->_remove_alias($collapsed_cond, $alias) },
1239 my $obj = $self->result_class->new(\%new);
1240 $obj->result_source($self->result_source) if $obj->can('result_source');
1246 # Recursively collapse the condition.
1248 sub _collapse_cond {
1249 my ($self, $cond, $collapsed) = @_;
1253 if (ref $cond eq 'ARRAY') {
1254 foreach my $subcond (@$cond) {
1255 next unless ref $subcond; # -or
1256 # warn "ARRAY: " . Dumper $subcond;
1257 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1260 elsif (ref $cond eq 'HASH') {
1261 if (keys %$cond and (keys %$cond)[0] eq '-and') {
1262 foreach my $subcond (@{$cond->{-and}}) {
1263 # warn "HASH: " . Dumper $subcond;
1264 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1268 # warn "LEAF: " . Dumper $cond;
1269 foreach my $col (keys %$cond) {
1270 my $value = $cond->{$col};
1271 $collapsed->{$col} = $value;
1281 # Remove the specified alias from the specified query hash. A copy is made so
1282 # the original query is not modified.
1285 my ($self, $query, $alias) = @_;
1287 my %unaliased = %{ $query || {} };
1288 foreach my $key (keys %unaliased) {
1289 $unaliased{$1} = delete $unaliased{$key}
1290 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
1300 =item Arguments: \%vals, \%attrs?
1302 =item Return Value: $object
1306 Find an existing record from this resultset. If none exists, instantiate a new
1307 result object and return it. The object will not be saved into your storage
1308 until you call L<DBIx::Class::Row/insert> on it.
1310 If you want objects to be saved immediately, use L</find_or_create> instead.
1316 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1317 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1318 my $exists = $self->find($hash, $attrs);
1319 return defined $exists ? $exists : $self->new_result($hash);
1326 =item Arguments: \%vals
1328 =item Return Value: $object
1332 Inserts a record into the resultset and returns the object representing it.
1334 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
1339 my ($self, $attrs) = @_;
1340 $self->throw_exception( "create needs a hashref" )
1341 unless ref $attrs eq 'HASH';
1342 return $self->new_result($attrs)->insert;
1345 =head2 find_or_create
1349 =item Arguments: \%vals, \%attrs?
1351 =item Return Value: $object
1355 $class->find_or_create({ key => $val, ... });
1357 Tries to find a record based on its primary key or unique constraint; if none
1358 is found, creates one and returns that instead.
1360 my $cd = $schema->resultset('CD')->find_or_create({
1362 artist => 'Massive Attack',
1363 title => 'Mezzanine',
1367 Also takes an optional C<key> attribute, to search by a specific key or unique
1368 constraint. For example:
1370 my $cd = $schema->resultset('CD')->find_or_create(
1372 artist => 'Massive Attack',
1373 title => 'Mezzanine',
1375 { key => 'cd_artist_title' }
1378 See also L</find> and L</update_or_create>. For information on how to declare
1379 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1383 sub find_or_create {
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 : $self->create($hash);
1391 =head2 update_or_create
1395 =item Arguments: \%col_values, { key => $unique_constraint }?
1397 =item Return Value: $object
1401 $class->update_or_create({ col => $val, ... });
1403 First, searches for an existing row matching one of the unique constraints
1404 (including the primary key) on the source of this resultset. If a row is
1405 found, updates it with the other given column values. Otherwise, creates a new
1408 Takes an optional C<key> attribute to search on a specific unique constraint.
1411 # In your application
1412 my $cd = $schema->resultset('CD')->update_or_create(
1414 artist => 'Massive Attack',
1415 title => 'Mezzanine',
1418 { key => 'cd_artist_title' }
1421 If no C<key> is specified, it searches on all unique constraints defined on the
1422 source, including the primary key.
1424 If the C<key> is specified as C<primary>, it searches only on the primary key.
1426 See also L</find> and L</find_or_create>. For information on how to declare
1427 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1431 sub update_or_create {
1433 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1434 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
1436 my $row = $self->find($cond, $attrs);
1438 $row->update($cond);
1442 return $self->create($cond);
1449 =item Arguments: none
1451 =item Return Value: \@cache_objects?
1455 Gets the contents of the cache for the resultset, if the cache is set.
1467 =item Arguments: \@cache_objects
1469 =item Return Value: \@cache_objects
1473 Sets the contents of the cache for the resultset. Expects an arrayref
1474 of objects of the same class as those produced by the resultset. Note that
1475 if the cache is set the resultset will return the cached objects rather
1476 than re-querying the database even if the cache attr is not set.
1481 my ( $self, $data ) = @_;
1482 $self->throw_exception("set_cache requires an arrayref")
1483 if defined($data) && (ref $data ne 'ARRAY');
1484 $self->{all_cache} = $data;
1491 =item Arguments: none
1493 =item Return Value: []
1497 Clears the cache for the resultset.
1502 shift->set_cache(undef);
1505 =head2 related_resultset
1509 =item Arguments: $relationship_name
1511 =item Return Value: $resultset
1515 Returns a related resultset for the supplied relationship name.
1517 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
1521 sub related_resultset {
1522 my ($self, $rel) = @_;
1524 $self->{related_resultsets} ||= {};
1525 return $self->{related_resultsets}{$rel} ||= do {
1526 my $rel_obj = $self->result_source->relationship_info($rel);
1528 $self->throw_exception(
1529 "search_related: result source '" . $self->result_source->name .
1530 "' has no such relationship $rel")
1533 my ($from,$seen) = $self->_resolve_from($rel);
1535 my $join_count = $seen->{$rel};
1536 my $alias = ($join_count > 1 ? join('_', $rel, $join_count) : $rel);
1538 $self->result_source->schema->resultset($rel_obj->{class})->search_rs(
1540 %{$self->{attrs}||{}},
1546 where => $self->{cond},
1554 my ($self, $extra_join) = @_;
1555 my $source = $self->result_source;
1556 my $attrs = $self->{attrs};
1558 my $from = $attrs->{from}
1559 || [ { $attrs->{alias} => $source->from } ];
1561 my $seen = { %{$attrs->{seen_join}||{}} };
1563 my $join = ($attrs->{join}
1564 ? [ $attrs->{join}, $extra_join ]
1568 ($join ? $source->resolve_join($join, $attrs->{alias}, $seen) : ()),
1571 return ($from,$seen);
1574 sub _resolved_attrs {
1576 return $self->{_attrs} if $self->{_attrs};
1578 my $attrs = { %{$self->{attrs}||{}} };
1579 my $source = $self->{result_source};
1580 my $alias = $attrs->{alias};
1582 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
1583 if ($attrs->{columns}) {
1584 delete $attrs->{as};
1585 } elsif (!$attrs->{select}) {
1586 $attrs->{columns} = [ $source->columns ];
1591 ? (ref $attrs->{select} eq 'ARRAY'
1592 ? [ @{$attrs->{select}} ]
1593 : [ $attrs->{select} ])
1594 : [ map { m/\./ ? $_ : "${alias}.$_" } @{delete $attrs->{columns}} ]
1598 ? (ref $attrs->{as} eq 'ARRAY'
1599 ? [ @{$attrs->{as}} ]
1601 : [ map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{$attrs->{select}} ]
1605 if ($adds = delete $attrs->{include_columns}) {
1606 $adds = [$adds] unless ref $adds eq 'ARRAY';
1607 push(@{$attrs->{select}}, @$adds);
1608 push(@{$attrs->{as}}, map { m/([^.]+)$/; $1 } @$adds);
1610 if ($adds = delete $attrs->{'+select'}) {
1611 $adds = [$adds] unless ref $adds eq 'ARRAY';
1612 push(@{$attrs->{select}},
1613 map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds);
1615 if (my $adds = delete $attrs->{'+as'}) {
1616 $adds = [$adds] unless ref $adds eq 'ARRAY';
1617 push(@{$attrs->{as}}, @$adds);
1620 $attrs->{from} ||= [ { 'me' => $source->from } ];
1622 if (exists $attrs->{join} || exists $attrs->{prefetch}) {
1623 my $join = delete $attrs->{join} || {};
1625 if (defined $attrs->{prefetch}) {
1626 $join = $self->_merge_attr(
1627 $join, $attrs->{prefetch}
1631 $attrs->{from} = # have to copy here to avoid corrupting the original
1634 $source->resolve_join($join, $alias, { %{$attrs->{seen_join}||{}} })
1638 $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct};
1639 if ($attrs->{order_by}) {
1640 $attrs->{order_by} = (ref($attrs->{order_by}) eq 'ARRAY'
1641 ? [ @{$attrs->{order_by}} ]
1642 : [ $attrs->{order_by} ]);
1644 $attrs->{order_by} = [];
1647 my $collapse = $attrs->{collapse} || {};
1648 if (my $prefetch = delete $attrs->{prefetch}) {
1649 $prefetch = $self->_merge_attr({}, $prefetch);
1651 my $seen = $attrs->{seen_join} || {};
1652 foreach my $p (ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch)) {
1653 # bring joins back to level of current class
1654 my @prefetch = $source->resolve_prefetch(
1655 $p, $alias, $seen, \@pre_order, $collapse
1657 push(@{$attrs->{select}}, map { $_->[0] } @prefetch);
1658 push(@{$attrs->{as}}, map { $_->[1] } @prefetch);
1660 push(@{$attrs->{order_by}}, @pre_order);
1662 $attrs->{collapse} = $collapse;
1664 return $self->{_attrs} = $attrs;
1668 my ($self, $a, $b) = @_;
1669 return $b unless defined($a);
1670 return $a unless defined($b);
1672 if (ref $b eq 'HASH' && ref $a eq 'HASH') {
1673 foreach my $key (keys %{$b}) {
1674 if (exists $a->{$key}) {
1675 $a->{$key} = $self->_merge_attr($a->{$key}, $b->{$key});
1677 $a->{$key} = $b->{$key};
1682 $a = [$a] unless ref $a eq 'ARRAY';
1683 $b = [$b] unless ref $b eq 'ARRAY';
1687 foreach my $x ($a, $b) {
1688 foreach my $element (@{$x}) {
1689 if (ref $element eq 'HASH') {
1690 $hash = $self->_merge_attr($hash, $element);
1691 } elsif (ref $element eq 'ARRAY') {
1692 push(@array, @{$element});
1694 push(@array, $element) unless $b == $x
1695 && grep { $_ eq $element } @array;
1700 @array = grep { !exists $hash->{$_} } @array;
1702 return keys %{$hash}
1711 =head2 throw_exception
1713 See L<DBIx::Class::Schema/throw_exception> for details.
1717 sub throw_exception {
1719 $self->result_source->schema->throw_exception(@_);
1722 # XXX: FIXME: Attributes docs need clearing up
1726 The resultset takes various attributes that modify its behavior. Here's an
1733 =item Value: ($order_by | \@order_by)
1737 Which column(s) to order the results by. This is currently passed
1738 through directly to SQL, so you can give e.g. C<year DESC> for a
1739 descending order on the column `year'.
1741 Please note that if you have quoting enabled (see
1742 L<DBIx::Class::Storage/quote_char>) you will need to do C<\'year DESC' > to
1743 specify an order. (The scalar ref causes it to be passed as raw sql to the DB,
1744 so you will need to manually quote things as appropriate.)
1750 =item Value: \@columns
1754 Shortcut to request a particular set of columns to be retrieved. Adds
1755 C<me.> onto the start of any column without a C<.> in it and sets C<select>
1756 from that, then auto-populates C<as> from C<select> as normal. (You may also
1757 use the C<cols> attribute, as in earlier versions of DBIC.)
1759 =head2 include_columns
1763 =item Value: \@columns
1767 Shortcut to include additional columns in the returned results - for example
1769 $schema->resultset('CD')->search(undef, {
1770 include_columns => ['artist.name'],
1774 would return all CDs and include a 'name' column to the information
1775 passed to object inflation
1781 =item Value: \@select_columns
1785 Indicates which columns should be selected from the storage. You can use
1786 column names, or in the case of RDBMS back ends, function or stored procedure
1789 $rs = $schema->resultset('Employee')->search(undef, {
1792 { count => 'employeeid' },
1797 When you use function/stored procedure names and do not supply an C<as>
1798 attribute, the column names returned are storage-dependent. E.g. MySQL would
1799 return a column named C<count(employeeid)> in the above example.
1805 Indicates additional columns to be selected from storage. Works the same as
1806 L<select> but adds columns to the selection.
1814 Indicates additional column names for those added via L<+select>.
1822 =item Value: \@inflation_names
1826 Indicates column names for object inflation. This is used in conjunction with
1827 C<select>, usually when C<select> contains one or more function or stored
1830 $rs = $schema->resultset('Employee')->search(undef, {
1833 { count => 'employeeid' }
1835 as => ['name', 'employee_count'],
1838 my $employee = $rs->first(); # get the first Employee
1840 If the object against which the search is performed already has an accessor
1841 matching a column name specified in C<as>, the value can be retrieved using
1842 the accessor as normal:
1844 my $name = $employee->name();
1846 If on the other hand an accessor does not exist in the object, you need to
1847 use C<get_column> instead:
1849 my $employee_count = $employee->get_column('employee_count');
1851 You can create your own accessors if required - see
1852 L<DBIx::Class::Manual::Cookbook> for details.
1854 Please note: This will NOT insert an C<AS employee_count> into the SQL
1855 statement produced, it is used for internal access only. Thus
1856 attempting to use the accessor in an C<order_by> clause or similar
1857 will fail miserably.
1859 To get around this limitation, you can supply literal SQL to your
1860 C<select> attibute that contains the C<AS alias> text, eg:
1862 select => [\'myfield AS alias']
1868 =item Value: ($rel_name | \@rel_names | \%rel_names)
1872 Contains a list of relationships that should be joined for this query. For
1875 # Get CDs by Nine Inch Nails
1876 my $rs = $schema->resultset('CD')->search(
1877 { 'artist.name' => 'Nine Inch Nails' },
1878 { join => 'artist' }
1881 Can also contain a hash reference to refer to the other relation's relations.
1884 package MyApp::Schema::Track;
1885 use base qw/DBIx::Class/;
1886 __PACKAGE__->table('track');
1887 __PACKAGE__->add_columns(qw/trackid cd position title/);
1888 __PACKAGE__->set_primary_key('trackid');
1889 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
1892 # In your application
1893 my $rs = $schema->resultset('Artist')->search(
1894 { 'track.title' => 'Teardrop' },
1896 join => { cd => 'track' },
1897 order_by => 'artist.name',
1901 You need to use the relationship (not the table) name in conditions,
1902 because they are aliased as such. The current table is aliased as "me", so
1903 you need to use me.column_name in order to avoid ambiguity. For example:
1905 # Get CDs from 1984 with a 'Foo' track
1906 my $rs = $schema->resultset('CD')->search(
1909 'tracks.name' => 'Foo'
1911 { join => 'tracks' }
1914 If the same join is supplied twice, it will be aliased to <rel>_2 (and
1915 similarly for a third time). For e.g.
1917 my $rs = $schema->resultset('Artist')->search({
1918 'cds.title' => 'Down to Earth',
1919 'cds_2.title' => 'Popular',
1921 join => [ qw/cds cds/ ],
1924 will return a set of all artists that have both a cd with title 'Down
1925 to Earth' and a cd with title 'Popular'.
1927 If you want to fetch related objects from other tables as well, see C<prefetch>
1934 =item Value: ($rel_name | \@rel_names | \%rel_names)
1938 Contains one or more relationships that should be fetched along with the main
1939 query (when they are accessed afterwards they will have already been
1940 "prefetched"). This is useful for when you know you will need the related
1941 objects, because it saves at least one query:
1943 my $rs = $schema->resultset('Tag')->search(
1952 The initial search results in SQL like the following:
1954 SELECT tag.*, cd.*, artist.* FROM tag
1955 JOIN cd ON tag.cd = cd.cdid
1956 JOIN artist ON cd.artist = artist.artistid
1958 L<DBIx::Class> has no need to go back to the database when we access the
1959 C<cd> or C<artist> relationships, which saves us two SQL statements in this
1962 Simple prefetches will be joined automatically, so there is no need
1963 for a C<join> attribute in the above search. If you're prefetching to
1964 depth (e.g. { cd => { artist => 'label' } or similar), you'll need to
1965 specify the join as well.
1967 C<prefetch> can be used with the following relationship types: C<belongs_to>,
1968 C<has_one> (or if you're using C<add_relationship>, any relationship declared
1969 with an accessor type of 'single' or 'filter').
1979 Makes the resultset paged and specifies the page to retrieve. Effectively
1980 identical to creating a non-pages resultset and then calling ->page($page)
1983 If L<rows> attribute is not specified it defualts to 10 rows per page.
1993 Specifes the maximum number of rows for direct retrieval or the number of
1994 rows per page if the page attribute or method is used.
2000 =item Value: $offset
2004 Specifies the (zero-based) row number for the first row to be returned, or the
2005 of the first row of the first page if paging is used.
2011 =item Value: \@columns
2015 A arrayref of columns to group by. Can include columns of joined tables.
2017 group_by => [qw/ column1 column2 ... /]
2023 =item Value: $condition
2027 HAVING is a select statement attribute that is applied between GROUP BY and
2028 ORDER BY. It is applied to the after the grouping calculations have been
2031 having => { 'count(employee)' => { '>=', 100 } }
2037 =item Value: (0 | 1)
2041 Set to 1 to group by all columns.
2047 Adds to the WHERE clause.
2049 # only return rows WHERE deleted IS NULL for all searches
2050 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
2052 Can be overridden by passing C<{ where => undef }> as an attribute
2059 Set to 1 to cache search results. This prevents extra SQL queries if you
2060 revisit rows in your ResultSet:
2062 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
2064 while( my $artist = $resultset->next ) {
2068 $rs->first; # without cache, this would issue a query
2070 By default, searches are not cached.
2072 For more examples of using these attributes, see
2073 L<DBIx::Class::Manual::Cookbook>.
2079 =item Value: \@from_clause
2083 The C<from> attribute gives you manual control over the C<FROM> clause of SQL
2084 statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
2087 NOTE: Use this on your own risk. This allows you to shoot off your foot!
2089 C<join> will usually do what you need and it is strongly recommended that you
2090 avoid using C<from> unless you cannot achieve the desired result using C<join>.
2091 And we really do mean "cannot", not just tried and failed. Attempting to use
2092 this because you're having problems with C<join> is like trying to use x86
2093 ASM because you've got a syntax error in your C. Trust us on this.
2095 Now, if you're still really, really sure you need to use this (and if you're
2096 not 100% sure, ask the mailing list first), here's an explanation of how this
2099 The syntax is as follows -
2102 { <alias1> => <table1> },
2104 { <alias2> => <table2>, -join_type => 'inner|left|right' },
2105 [], # nested JOIN (optional)
2106 { <table1.column1> => <table2.column2>, ... (more conditions) },
2108 # More of the above [ ] may follow for additional joins
2115 ON <table1.column1> = <table2.column2>
2116 <more joins may follow>
2118 An easy way to follow the examples below is to remember the following:
2120 Anything inside "[]" is a JOIN
2121 Anything inside "{}" is a condition for the enclosing JOIN
2123 The following examples utilize a "person" table in a family tree application.
2124 In order to express parent->child relationships, this table is self-joined:
2126 # Person->belongs_to('father' => 'Person');
2127 # Person->belongs_to('mother' => 'Person');
2129 C<from> can be used to nest joins. Here we return all children with a father,
2130 then search against all mothers of those children:
2132 $rs = $schema->resultset('Person')->search(
2135 alias => 'mother', # alias columns in accordance with "from"
2137 { mother => 'person' },
2140 { child => 'person' },
2142 { father => 'person' },
2143 { 'father.person_id' => 'child.father_id' }
2146 { 'mother.person_id' => 'child.mother_id' }
2153 # SELECT mother.* FROM person mother
2156 # JOIN person father
2157 # ON ( father.person_id = child.father_id )
2159 # ON ( mother.person_id = child.mother_id )
2161 The type of any join can be controlled manually. To search against only people
2162 with a father in the person table, we could explicitly use C<INNER JOIN>:
2164 $rs = $schema->resultset('Person')->search(
2167 alias => 'child', # alias columns in accordance with "from"
2169 { child => 'person' },
2171 { father => 'person', -join_type => 'inner' },
2172 { 'father.id' => 'child.father_id' }
2179 # SELECT child.* FROM person child
2180 # INNER JOIN person father ON child.father_id = father.id