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")
190 ? $self->throw_exception("Odd number of arguments to search")
197 if (defined $where) {
198 $new_attrs->{where} = (
199 defined $new_attrs->{where}
202 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
203 } $where, $new_attrs->{where}
209 $new_attrs->{where} = (
210 defined $new_attrs->{where}
213 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
214 } $cond, $new_attrs->{where}
220 if (defined $having) {
221 $new_attrs->{having} = (
222 defined $new_attrs->{having}
225 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
226 } $having, $new_attrs->{having}
232 my $rs = (ref $self)->new($self->result_source, $new_attrs);
234 $rs->set_cache($rows);
239 =head2 search_literal
243 =item Arguments: $sql_fragment, @bind_values
245 =item Return Value: $resultset (scalar context), @row_objs (list context)
249 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
250 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
252 Pass a literal chunk of SQL to be added to the conditional part of the
258 my ($self, $cond, @vals) = @_;
259 my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {});
260 $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ];
261 return $self->search(\$cond, $attrs);
268 =item Arguments: @values | \%cols, \%attrs?
270 =item Return Value: $row_object
274 Finds a row based on its primary key or unique constraint. For example, to find
275 a row by its primary key:
277 my $cd = $schema->resultset('CD')->find(5);
279 You can also find a row by a specific unique constraint using the C<key>
280 attribute. For example:
282 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
283 key => 'cd_artist_title'
286 Additionally, you can specify the columns explicitly by name:
288 my $cd = $schema->resultset('CD')->find(
290 artist => 'Massive Attack',
291 title => 'Mezzanine',
293 { key => 'cd_artist_title' }
296 If the C<key> is specified as C<primary>, it searches only on the primary key.
298 If no C<key> is specified, it searches on all unique constraints defined on the
299 source, including the primary key.
301 If your table does not have a primary key, you B<must> provide a value for the
302 C<key> attribute matching one of the unique constraints on the source.
304 See also L</find_or_create> and L</update_or_create>. For information on how to
305 declare unique constraints, see
306 L<DBIx::Class::ResultSource/add_unique_constraint>.
312 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
314 # Default to the primary key, but allow a specific key
315 my @cols = exists $attrs->{key}
316 ? $self->result_source->unique_constraint_columns($attrs->{key})
317 : $self->result_source->primary_columns;
318 $self->throw_exception(
319 "Can't find unless a primary key is defined or unique constraint is specified"
322 # Parse out a hashref from input
324 if (ref $_[0] eq 'HASH') {
325 $input_query = { %{$_[0]} };
327 elsif (@_ == @cols) {
329 @{$input_query}{@cols} = @_;
332 # Compatibility: Allow e.g. find(id => $value)
333 carp "Find by key => value deprecated; please use a hashref instead";
337 my @unique_queries = $self->_unique_queries($input_query, $attrs);
339 # Build the final query: Default to the disjunction of the unique queries,
340 # but allow the input query in case the ResultSet defines the query or the
341 # user is abusing find
342 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
343 my $query = @unique_queries
344 ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
345 : $self->_add_alias($input_query, $alias);
349 my $rs = $self->search($query, $attrs);
350 return keys %{$rs->_resolved_attrs->{collapse}} ? $rs->next : $rs->single;
353 return keys %{$self->_resolved_attrs->{collapse}}
354 ? $self->search($query)->next
355 : $self->single($query);
361 # Add the specified alias to the specified query hash. A copy is made so the
362 # original query is not modified.
365 my ($self, $query, $alias) = @_;
367 my %aliased = %$query;
368 foreach my $col (grep { ! m/\./ } keys %aliased) {
369 $aliased{"$alias.$col"} = delete $aliased{$col};
377 # Build a list of queries which satisfy unique constraints.
379 sub _unique_queries {
380 my ($self, $query, $attrs) = @_;
382 my @constraint_names = exists $attrs->{key}
384 : $self->result_source->unique_constraint_names;
387 foreach my $name (@constraint_names) {
388 my @unique_cols = $self->result_source->unique_constraint_columns($name);
389 my $unique_query = $self->_build_unique_query($query, \@unique_cols);
391 my $num_query = scalar keys %$unique_query;
392 next unless $num_query;
394 # XXX: Assuming quite a bit about $self->{attrs}{where}
395 my $num_cols = scalar @unique_cols;
396 my $num_where = exists $self->{attrs}{where}
397 ? scalar keys %{ $self->{attrs}{where} }
399 push @unique_queries, $unique_query
400 if $num_query + $num_where == $num_cols;
403 return @unique_queries;
406 # _build_unique_query
408 # Constrain the specified query hash based on the specified column names.
410 sub _build_unique_query {
411 my ($self, $query, $unique_cols) = @_;
414 map { $_ => $query->{$_} }
415 grep { exists $query->{$_} }
420 =head2 search_related
424 =item Arguments: $rel, $cond, \%attrs?
426 =item Return Value: $new_resultset
430 $new_rs = $cd_rs->search_related('artist', {
434 Searches the specified relationship, optionally specifying a condition and
435 attributes for matching records. See L</ATTRIBUTES> for more information.
440 return shift->related_resultset(shift)->search(@_);
447 =item Arguments: none
449 =item Return Value: $cursor
453 Returns a storage-driven cursor to the given resultset. See
454 L<DBIx::Class::Cursor> for more information.
461 my $attrs = { %{$self->_resolved_attrs} };
462 return $self->{cursor}
463 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
464 $attrs->{where},$attrs);
471 =item Arguments: $cond?
473 =item Return Value: $row_object?
477 my $cd = $schema->resultset('CD')->single({ year => 2001 });
479 Inflates the first result without creating a cursor if the resultset has
480 any records in it; if not returns nothing. Used by L</find> as an optimisation.
482 Can optionally take an additional condition *only* - this is a fast-code-path
483 method; if you need to add extra joins or similar call ->search and then
484 ->single without a condition on the $rs returned from that.
489 my ($self, $where) = @_;
490 my $attrs = { %{$self->_resolved_attrs} };
492 if (defined $attrs->{where}) {
495 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
496 $where, delete $attrs->{where} ]
499 $attrs->{where} = $where;
503 # XXX: Disabled since it doesn't infer uniqueness in all cases
504 # unless ($self->_is_unique_query($attrs->{where})) {
505 # carp "Query not guaranteed to return a single row"
506 # . "; please declare your unique constraints or use search instead";
509 my @data = $self->result_source->storage->select_single(
510 $attrs->{from}, $attrs->{select},
511 $attrs->{where}, $attrs
514 return (@data ? $self->_construct_object(@data) : ());
519 # Try to determine if the specified query is guaranteed to be unique, based on
520 # the declared unique constraints.
522 sub _is_unique_query {
523 my ($self, $query) = @_;
525 my $collapsed = $self->_collapse_query($query);
526 my $alias = $self->{attrs}{alias};
528 foreach my $name ($self->result_source->unique_constraint_names) {
529 my @unique_cols = map {
531 } $self->result_source->unique_constraint_columns($name);
533 # Count the values for each unique column
534 my %seen = map { $_ => 0 } @unique_cols;
536 foreach my $key (keys %$collapsed) {
537 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
538 next unless exists $seen{$aliased}; # Additional constraints are okay
539 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
542 # If we get 0 or more than 1 value for a column, it's not necessarily unique
543 return 1 unless grep { $_ != 1 } values %seen;
551 # Recursively collapse the query, accumulating values for each column.
553 sub _collapse_query {
554 my ($self, $query, $collapsed) = @_;
558 if (ref $query eq 'ARRAY') {
559 foreach my $subquery (@$query) {
560 next unless ref $subquery; # -or
561 # warn "ARRAY: " . Dumper $subquery;
562 $collapsed = $self->_collapse_query($subquery, $collapsed);
565 elsif (ref $query eq 'HASH') {
566 if (keys %$query and (keys %$query)[0] eq '-and') {
567 foreach my $subquery (@{$query->{-and}}) {
568 # warn "HASH: " . Dumper $subquery;
569 $collapsed = $self->_collapse_query($subquery, $collapsed);
573 # warn "LEAF: " . Dumper $query;
574 foreach my $col (keys %$query) {
575 my $value = $query->{$col};
576 $collapsed->{$col}{$value}++;
588 =item Arguments: $cond?
590 =item Return Value: $resultsetcolumn
594 my $max_length = $rs->get_column('length')->max;
596 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
601 my ($self, $column) = @_;
602 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
610 =item Arguments: $cond, \%attrs?
612 =item Return Value: $resultset (scalar context), @row_objs (list context)
616 # WHERE title LIKE '%blue%'
617 $cd_rs = $rs->search_like({ title => '%blue%'});
619 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
620 that this is simply a convenience method. You most likely want to use
621 L</search> with specific operators.
623 For more information, see L<DBIx::Class::Manual::Cookbook>.
629 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
630 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
631 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
632 return $class->search($query, { %$attrs });
639 =item Arguments: $first, $last
641 =item Return Value: $resultset (scalar context), @row_objs (list context)
645 Returns a resultset or object list representing a subset of elements from the
646 resultset slice is called on. Indexes are from 0, i.e., to get the first
649 my ($one, $two, $three) = $rs->slice(0, 2);
654 my ($self, $min, $max) = @_;
655 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
656 $attrs->{offset} = $self->{attrs}{offset} || 0;
657 $attrs->{offset} += $min;
658 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
659 return $self->search(undef(), $attrs);
660 #my $slice = (ref $self)->new($self->result_source, $attrs);
661 #return (wantarray ? $slice->all : $slice);
668 =item Arguments: none
670 =item Return Value: $result?
674 Returns the next element in the resultset (C<undef> is there is none).
676 Can be used to efficiently iterate over records in the resultset:
678 my $rs = $schema->resultset('CD')->search;
679 while (my $cd = $rs->next) {
683 Note that you need to store the resultset object, and call C<next> on it.
684 Calling C<< resultset('Table')->next >> repeatedly will always return the
685 first record from the resultset.
691 if (my $cache = $self->get_cache) {
692 $self->{all_cache_position} ||= 0;
693 return $cache->[$self->{all_cache_position}++];
695 if ($self->{attrs}{cache}) {
696 $self->{all_cache_position} = 1;
697 return ($self->all)[0];
700 exists $self->{stashed_row}
701 ? @{delete $self->{stashed_row}}
702 : $self->cursor->next
704 return unless (@row);
705 return $self->_construct_object(@row);
708 sub _construct_object {
709 my ($self, @row) = @_;
710 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row);
711 my $new = $self->result_class->inflate_result($self->result_source, @$info);
712 $new = $self->{_attrs}{record_filter}->($new)
713 if exists $self->{_attrs}{record_filter};
717 sub _collapse_result {
718 my ($self, $as, $row, $prefix) = @_;
723 foreach my $this_as (@$as) {
724 my $val = shift @copy;
725 if (defined $prefix) {
726 if ($this_as =~ m/^\Q${prefix}.\E(.+)$/) {
728 $remain =~ /^(?:(.*)\.)?([^.]+)$/;
729 $const{$1||''}{$2} = $val;
732 $this_as =~ /^(?:(.*)\.)?([^.]+)$/;
733 $const{$1||''}{$2} = $val;
737 my $alias = $self->{attrs}{alias};
738 my $info = [ {}, {} ];
739 foreach my $key (keys %const) {
740 if (length $key && $key ne $alias) {
742 my @parts = split(/\./, $key);
743 foreach my $p (@parts) {
744 $target = $target->[1]->{$p} ||= [];
746 $target->[0] = $const{$key};
748 $info->[0] = $const{$key};
753 if (defined $prefix) {
755 m/^\Q${prefix}.\E(.+)$/ ? ($1) : ()
756 } keys %{$self->{_attrs}{collapse}}
758 @collapse = keys %{$self->{_attrs}{collapse}};
762 my ($c) = sort { length $a <=> length $b } @collapse;
764 foreach my $p (split(/\./, $c)) {
765 $target = $target->[1]->{$p} ||= [];
767 my $c_prefix = (defined($prefix) ? "${prefix}.${c}" : $c);
768 my @co_key = @{$self->{_attrs}{collapse}{$c_prefix}};
769 my $tree = $self->_collapse_result($as, $row, $c_prefix);
770 my %co_check = map { ($_, $tree->[0]->{$_}); } @co_key;
776 !defined($tree->[0]->{$_}) || $co_check{$_} ne $tree->[0]->{$_}
781 last unless (@raw = $self->cursor->next);
782 $row = $self->{stashed_row} = \@raw;
783 $tree = $self->_collapse_result($as, $row, $c_prefix);
785 @$target = (@final ? @final : [ {}, {} ]);
786 # single empty result to indicate an empty prefetched has_many
789 #print "final info: " . Dumper($info);
797 =item Arguments: $result_source?
799 =item Return Value: $result_source
803 An accessor for the primary ResultSource object from which this ResultSet
810 =item Arguments: $result_class?
812 =item Return Value: $result_class
816 An accessor for the class to use when creating row objects. Defaults to
817 C<< result_source->result_class >> - which in most cases is the name of the
818 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
827 =item Arguments: $cond, \%attrs??
829 =item Return Value: $count
833 Performs an SQL C<COUNT> with the same query as the resultset was built
834 with to find the number of elements. If passed arguments, does a search
835 on the resultset and counts the results of that.
837 Note: When using C<count> with C<group_by>, L<DBIX::Class> emulates C<GROUP BY>
838 using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do
839 not support C<DISTINCT> with multiple columns. If you are using such a
840 database, you should only use columns from the main table in your C<group_by>
847 return $self->search(@_)->count if @_ and defined $_[0];
848 return scalar @{ $self->get_cache } if $self->get_cache;
849 my $count = $self->_count;
850 return 0 unless $count;
852 $count -= $self->{attrs}{offset} if $self->{attrs}{offset};
853 $count = $self->{attrs}{rows} if
854 $self->{attrs}{rows} and $self->{attrs}{rows} < $count;
858 sub _count { # Separated out so pager can get the full count
860 my $select = { count => '*' };
862 my $attrs = { %{$self->_resolved_attrs} };
863 if (my $group_by = delete $attrs->{group_by}) {
864 delete $attrs->{having};
865 my @distinct = (ref $group_by ? @$group_by : ($group_by));
866 # todo: try CONCAT for multi-column pk
867 my @pk = $self->result_source->primary_columns;
869 my $alias = $attrs->{alias};
870 foreach my $column (@distinct) {
871 if ($column =~ qr/^(?:\Q${alias}.\E)?$pk[0]$/) {
872 @distinct = ($column);
878 $select = { count => { distinct => \@distinct } };
881 $attrs->{select} = $select;
882 $attrs->{as} = [qw/count/];
884 # offset, order by and page are not needed to count. record_filter is cdbi
885 delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/;
887 my $tmp_rs = (ref $self)->new($self->result_source, $attrs);
888 my ($count) = $tmp_rs->cursor->next;
896 =item Arguments: $sql_fragment, @bind_values
898 =item Return Value: $count
902 Counts the results in a literal query. Equivalent to calling L</search_literal>
903 with the passed arguments, then L</count>.
907 sub count_literal { shift->search_literal(@_)->count; }
913 =item Arguments: none
915 =item Return Value: @objects
919 Returns all elements in the resultset. Called implicitly if the resultset
920 is returned in list context.
926 return @{ $self->get_cache } if $self->get_cache;
930 # TODO: don't call resolve here
931 if (keys %{$self->_resolved_attrs->{collapse}}) {
932 # if ($self->{attrs}{prefetch}) {
933 # Using $self->cursor->all is really just an optimisation.
934 # If we're collapsing has_many prefetches it probably makes
935 # very little difference, and this is cleaner than hacking
936 # _construct_object to survive the approach
937 my @row = $self->cursor->next;
939 push(@obj, $self->_construct_object(@row));
940 @row = (exists $self->{stashed_row}
941 ? @{delete $self->{stashed_row}}
942 : $self->cursor->next);
945 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
948 $self->set_cache(\@obj) if $self->{attrs}{cache};
956 =item Arguments: none
958 =item Return Value: $self
962 Resets the resultset's cursor, so you can iterate through the elements again.
968 delete $self->{_attrs} if exists $self->{_attrs};
969 $self->{all_cache_position} = 0;
970 $self->cursor->reset;
978 =item Arguments: none
980 =item Return Value: $object?
984 Resets the resultset and returns an object for the first result (if the
985 resultset returns anything).
990 return $_[0]->reset->next;
993 # _cond_for_update_delete
995 # update/delete require the condition to be modified to handle
996 # the differing SQL syntax available. This transforms the $self->{cond}
997 # appropriately, returning the new condition.
999 sub _cond_for_update_delete {
1000 my ($self, $full_cond) = @_;
1003 $full_cond ||= $self->{cond};
1004 # No-op. No condition, we're updating/deleting everything
1005 return $cond unless ref $full_cond;
1007 if (ref $full_cond eq 'ARRAY') {
1011 foreach my $key (keys %{$_}) {
1013 $hash{$1} = $_->{$key};
1019 elsif (ref $full_cond eq 'HASH') {
1020 if ((keys %{$full_cond})[0] eq '-and') {
1023 my @cond = @{$full_cond->{-and}};
1024 for (my $i = 0; $i < @cond; $i++) {
1025 my $entry = $cond[$i];
1028 if (ref $entry eq 'HASH') {
1029 $hash = $self->_cond_for_update_delete($entry);
1032 $entry =~ /([^.]+)$/;
1033 $hash->{$1} = $cond[++$i];
1036 push @{$cond->{-and}}, $hash;
1040 foreach my $key (keys %{$full_cond}) {
1042 $cond->{$1} = $full_cond->{$key};
1047 $self->throw_exception(
1048 "Can't update/delete on resultset with condition unless hash or array"
1060 =item Arguments: \%values
1062 =item Return Value: $storage_rv
1066 Sets the specified columns in the resultset to the supplied values in a
1067 single query. Return value will be true if the update succeeded or false
1068 if no records were updated; exact type of success value is storage-dependent.
1073 my ($self, $values) = @_;
1074 $self->throw_exception("Values for update must be a hash")
1075 unless ref $values eq 'HASH';
1077 my $cond = $self->_cond_for_update_delete;
1079 return $self->result_source->storage->update(
1080 $self->result_source->from, $values, $cond
1088 =item Arguments: \%values
1090 =item Return Value: 1
1094 Fetches all objects and updates them one at a time. Note that C<update_all>
1095 will run DBIC cascade triggers, while L</update> will not.
1100 my ($self, $values) = @_;
1101 $self->throw_exception("Values for update must be a hash")
1102 unless ref $values eq 'HASH';
1103 foreach my $obj ($self->all) {
1104 $obj->set_columns($values)->update;
1113 =item Arguments: none
1115 =item Return Value: 1
1119 Deletes the contents of the resultset from its result source. Note that this
1120 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1121 to run. See also L<DBIx::Class::Row/delete>.
1128 my $cond = $self->_cond_for_update_delete;
1130 $self->result_source->storage->delete($self->result_source->from, $cond);
1138 =item Arguments: none
1140 =item Return Value: 1
1144 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1145 will run DBIC cascade triggers, while L</delete> will not.
1151 $_->delete for $self->all;
1159 =item Arguments: none
1161 =item Return Value: $pager
1165 Return Value a L<Data::Page> object for the current resultset. Only makes
1166 sense for queries with a C<page> attribute.
1172 my $attrs = $self->{attrs};
1173 $self->throw_exception("Can't create pager for non-paged rs")
1174 unless $self->{attrs}{page};
1175 $attrs->{rows} ||= 10;
1176 return $self->{pager} ||= Data::Page->new(
1177 $self->_count, $attrs->{rows}, $self->{attrs}{page});
1184 =item Arguments: $page_number
1186 =item Return Value: $rs
1190 Returns a resultset for the $page_number page of the resultset on which page
1191 is called, where each page contains a number of rows equal to the 'rows'
1192 attribute set on the resultset (10 by default).
1197 my ($self, $page) = @_;
1198 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1205 =item Arguments: \%vals
1207 =item Return Value: $object
1211 Creates an object in the resultset's result class and returns it.
1216 my ($self, $values) = @_;
1217 $self->throw_exception( "new_result needs a hash" )
1218 unless (ref $values eq 'HASH');
1219 $self->throw_exception(
1220 "Can't abstract implicit construct, condition not a hash"
1221 ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
1223 my $alias = $self->{attrs}{alias};
1224 my $collapsed_cond = $self->{cond} ? $self->_collapse_cond($self->{cond}) : {};
1226 %{ $self->_remove_alias($values, $alias) },
1227 %{ $self->_remove_alias($collapsed_cond, $alias) },
1230 my $obj = $self->result_class->new(\%new);
1231 $obj->result_source($self->result_source) if $obj->can('result_source');
1237 # Recursively collapse the condition.
1239 sub _collapse_cond {
1240 my ($self, $cond, $collapsed) = @_;
1244 if (ref $cond eq 'ARRAY') {
1245 foreach my $subcond (@$cond) {
1246 next unless ref $subcond; # -or
1247 # warn "ARRAY: " . Dumper $subcond;
1248 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1251 elsif (ref $cond eq 'HASH') {
1252 if (keys %$cond and (keys %$cond)[0] eq '-and') {
1253 foreach my $subcond (@{$cond->{-and}}) {
1254 # warn "HASH: " . Dumper $subcond;
1255 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1259 # warn "LEAF: " . Dumper $cond;
1260 foreach my $col (keys %$cond) {
1261 my $value = $cond->{$col};
1262 $collapsed->{$col} = $value;
1272 # Remove the specified alias from the specified query hash. A copy is made so
1273 # the original query is not modified.
1276 my ($self, $query, $alias) = @_;
1278 my %unaliased = %{ $query || {} };
1279 foreach my $key (keys %unaliased) {
1280 $unaliased{$1} = delete $unaliased{$key}
1281 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
1291 =item Arguments: \%vals, \%attrs?
1293 =item Return Value: $object
1297 Find an existing record from this resultset. If none exists, instantiate a new
1298 result object and return it. The object will not be saved into your storage
1299 until you call L<DBIx::Class::Row/insert> on it.
1301 If you want objects to be saved immediately, use L</find_or_create> instead.
1307 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1308 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1309 my $exists = $self->find($hash, $attrs);
1310 return defined $exists ? $exists : $self->new_result($hash);
1317 =item Arguments: \%vals
1319 =item Return Value: $object
1323 Inserts a record into the resultset and returns the object representing it.
1325 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
1330 my ($self, $attrs) = @_;
1331 $self->throw_exception( "create needs a hashref" )
1332 unless ref $attrs eq 'HASH';
1333 return $self->new_result($attrs)->insert;
1336 =head2 find_or_create
1340 =item Arguments: \%vals, \%attrs?
1342 =item Return Value: $object
1346 $class->find_or_create({ key => $val, ... });
1348 Tries to find a record based on its primary key or unique constraint; if none
1349 is found, creates one and returns that instead.
1351 my $cd = $schema->resultset('CD')->find_or_create({
1353 artist => 'Massive Attack',
1354 title => 'Mezzanine',
1358 Also takes an optional C<key> attribute, to search by a specific key or unique
1359 constraint. For example:
1361 my $cd = $schema->resultset('CD')->find_or_create(
1363 artist => 'Massive Attack',
1364 title => 'Mezzanine',
1366 { key => 'cd_artist_title' }
1369 See also L</find> and L</update_or_create>. For information on how to declare
1370 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1374 sub find_or_create {
1376 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1377 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1378 my $exists = $self->find($hash, $attrs);
1379 return defined $exists ? $exists : $self->create($hash);
1382 =head2 update_or_create
1386 =item Arguments: \%col_values, { key => $unique_constraint }?
1388 =item Return Value: $object
1392 $class->update_or_create({ col => $val, ... });
1394 First, searches for an existing row matching one of the unique constraints
1395 (including the primary key) on the source of this resultset. If a row is
1396 found, updates it with the other given column values. Otherwise, creates a new
1399 Takes an optional C<key> attribute to search on a specific unique constraint.
1402 # In your application
1403 my $cd = $schema->resultset('CD')->update_or_create(
1405 artist => 'Massive Attack',
1406 title => 'Mezzanine',
1409 { key => 'cd_artist_title' }
1412 If no C<key> is specified, it searches on all unique constraints defined on the
1413 source, including the primary key.
1415 If the C<key> is specified as C<primary>, it searches only on the primary key.
1417 See also L</find> and L</find_or_create>. For information on how to declare
1418 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1422 sub update_or_create {
1424 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1425 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
1427 my $row = $self->find($cond, $attrs);
1429 $row->update($cond);
1433 return $self->create($cond);
1440 =item Arguments: none
1442 =item Return Value: \@cache_objects?
1446 Gets the contents of the cache for the resultset, if the cache is set.
1458 =item Arguments: \@cache_objects
1460 =item Return Value: \@cache_objects
1464 Sets the contents of the cache for the resultset. Expects an arrayref
1465 of objects of the same class as those produced by the resultset. Note that
1466 if the cache is set the resultset will return the cached objects rather
1467 than re-querying the database even if the cache attr is not set.
1472 my ( $self, $data ) = @_;
1473 $self->throw_exception("set_cache requires an arrayref")
1474 if defined($data) && (ref $data ne 'ARRAY');
1475 $self->{all_cache} = $data;
1482 =item Arguments: none
1484 =item Return Value: []
1488 Clears the cache for the resultset.
1493 shift->set_cache(undef);
1496 =head2 related_resultset
1500 =item Arguments: $relationship_name
1502 =item Return Value: $resultset
1506 Returns a related resultset for the supplied relationship name.
1508 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
1512 sub related_resultset {
1513 my ($self, $rel) = @_;
1515 $self->{related_resultsets} ||= {};
1516 return $self->{related_resultsets}{$rel} ||= do {
1517 my $rel_obj = $self->result_source->relationship_info($rel);
1519 $self->throw_exception(
1520 "search_related: result source '" . $self->result_source->name .
1521 "' has no such relationship $rel")
1524 my ($from,$seen) = $self->_resolve_from($rel);
1526 my $join_count = $seen->{$rel};
1527 my $alias = ($join_count > 1 ? join('_', $rel, $join_count) : $rel);
1529 $self->result_source->schema->resultset($rel_obj->{class})->search_rs(
1531 %{$self->{attrs}||{}},
1537 where => $self->{cond},
1545 my ($self, $extra_join) = @_;
1546 my $source = $self->result_source;
1547 my $attrs = $self->{attrs};
1549 my $from = $attrs->{from}
1550 || [ { $attrs->{alias} => $source->from } ];
1552 my $seen = { %{$attrs->{seen_join}||{}} };
1554 my $join = ($attrs->{join}
1555 ? [ $attrs->{join}, $extra_join ]
1559 ($join ? $source->resolve_join($join, $attrs->{alias}, $seen) : ()),
1562 return ($from,$seen);
1565 sub _resolved_attrs {
1567 return $self->{_attrs} if $self->{_attrs};
1569 my $attrs = { %{$self->{attrs}||{}} };
1570 my $source = $self->{result_source};
1571 my $alias = $attrs->{alias};
1573 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
1574 if ($attrs->{columns}) {
1575 delete $attrs->{as};
1576 } elsif (!$attrs->{select}) {
1577 $attrs->{columns} = [ $source->columns ];
1582 ? (ref $attrs->{select} eq 'ARRAY'
1583 ? [ @{$attrs->{select}} ]
1584 : [ $attrs->{select} ])
1585 : [ map { m/\./ ? $_ : "${alias}.$_" } @{delete $attrs->{columns}} ]
1589 ? (ref $attrs->{as} eq 'ARRAY'
1590 ? [ @{$attrs->{as}} ]
1592 : [ map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{$attrs->{select}} ]
1596 if ($adds = delete $attrs->{include_columns}) {
1597 $adds = [$adds] unless ref $adds eq 'ARRAY';
1598 push(@{$attrs->{select}}, @$adds);
1599 push(@{$attrs->{as}}, map { m/([^.]+)$/; $1 } @$adds);
1601 if ($adds = delete $attrs->{'+select'}) {
1602 $adds = [$adds] unless ref $adds eq 'ARRAY';
1603 push(@{$attrs->{select}},
1604 map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds);
1606 if (my $adds = delete $attrs->{'+as'}) {
1607 $adds = [$adds] unless ref $adds eq 'ARRAY';
1608 push(@{$attrs->{as}}, @$adds);
1611 $attrs->{from} ||= [ { 'me' => $source->from } ];
1613 if (exists $attrs->{join} || exists $attrs->{prefetch}) {
1614 my $join = delete $attrs->{join} || {};
1616 if (defined $attrs->{prefetch}) {
1617 $join = $self->_merge_attr(
1618 $join, $attrs->{prefetch}
1622 $attrs->{from} = # have to copy here to avoid corrupting the original
1625 $source->resolve_join($join, $alias, { %{$attrs->{seen_join}||{}} })
1629 $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct};
1630 if ($attrs->{order_by}) {
1631 $attrs->{order_by} = (ref($attrs->{order_by}) eq 'ARRAY'
1632 ? [ @{$attrs->{order_by}} ]
1633 : [ $attrs->{order_by} ]);
1635 $attrs->{order_by} = [];
1638 my $collapse = $attrs->{collapse} || {};
1639 if (my $prefetch = delete $attrs->{prefetch}) {
1640 $prefetch = $self->_merge_attr({}, $prefetch);
1642 my $seen = $attrs->{seen_join} || {};
1643 foreach my $p (ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch)) {
1644 # bring joins back to level of current class
1645 my @prefetch = $source->resolve_prefetch(
1646 $p, $alias, $seen, \@pre_order, $collapse
1648 push(@{$attrs->{select}}, map { $_->[0] } @prefetch);
1649 push(@{$attrs->{as}}, map { $_->[1] } @prefetch);
1651 push(@{$attrs->{order_by}}, @pre_order);
1653 $attrs->{collapse} = $collapse;
1655 return $self->{_attrs} = $attrs;
1659 my ($self, $a, $b) = @_;
1660 return $b unless defined($a);
1661 return $a unless defined($b);
1663 if (ref $b eq 'HASH' && ref $a eq 'HASH') {
1664 foreach my $key (keys %{$b}) {
1665 if (exists $a->{$key}) {
1666 $a->{$key} = $self->_merge_attr($a->{$key}, $b->{$key});
1668 $a->{$key} = $b->{$key};
1673 $a = [$a] unless ref $a eq 'ARRAY';
1674 $b = [$b] unless ref $b eq 'ARRAY';
1678 foreach my $x ($a, $b) {
1679 foreach my $element (@{$x}) {
1680 if (ref $element eq 'HASH') {
1681 $hash = $self->_merge_attr($hash, $element);
1682 } elsif (ref $element eq 'ARRAY') {
1683 push(@array, @{$element});
1685 push(@array, $element) unless $b == $x
1686 && grep { $_ eq $element } @array;
1691 @array = grep { !exists $hash->{$_} } @array;
1693 return keys %{$hash}
1702 =head2 throw_exception
1704 See L<DBIx::Class::Schema/throw_exception> for details.
1708 sub throw_exception {
1710 $self->result_source->schema->throw_exception(@_);
1713 # XXX: FIXME: Attributes docs need clearing up
1717 The resultset takes various attributes that modify its behavior. Here's an
1724 =item Value: ($order_by | \@order_by)
1728 Which column(s) to order the results by. This is currently passed
1729 through directly to SQL, so you can give e.g. C<year DESC> for a
1730 descending order on the column `year'.
1732 Please note that if you have C<quote_char> enabled (see
1733 L<DBIx::Class::Storage::DBI/connect_info>) you will need to do C<\'year DESC' > to
1734 specify an order. (The scalar ref causes it to be passed as raw sql to the DB,
1735 so you will need to manually quote things as appropriate.)
1741 =item Value: \@columns
1745 Shortcut to request a particular set of columns to be retrieved. Adds
1746 C<me.> onto the start of any column without a C<.> in it and sets C<select>
1747 from that, then auto-populates C<as> from C<select> as normal. (You may also
1748 use the C<cols> attribute, as in earlier versions of DBIC.)
1750 =head2 include_columns
1754 =item Value: \@columns
1758 Shortcut to include additional columns in the returned results - for example
1760 $schema->resultset('CD')->search(undef, {
1761 include_columns => ['artist.name'],
1765 would return all CDs and include a 'name' column to the information
1766 passed to object inflation
1772 =item Value: \@select_columns
1776 Indicates which columns should be selected from the storage. You can use
1777 column names, or in the case of RDBMS back ends, function or stored procedure
1780 $rs = $schema->resultset('Employee')->search(undef, {
1783 { count => 'employeeid' },
1788 When you use function/stored procedure names and do not supply an C<as>
1789 attribute, the column names returned are storage-dependent. E.g. MySQL would
1790 return a column named C<count(employeeid)> in the above example.
1796 Indicates additional columns to be selected from storage. Works the same as
1797 L<select> but adds columns to the selection.
1805 Indicates additional column names for those added via L<+select>.
1813 =item Value: \@inflation_names
1817 Indicates column names for object inflation. This is used in conjunction with
1818 C<select>, usually when C<select> contains one or more function or stored
1821 $rs = $schema->resultset('Employee')->search(undef, {
1824 { count => 'employeeid' }
1826 as => ['name', 'employee_count'],
1829 my $employee = $rs->first(); # get the first Employee
1831 If the object against which the search is performed already has an accessor
1832 matching a column name specified in C<as>, the value can be retrieved using
1833 the accessor as normal:
1835 my $name = $employee->name();
1837 If on the other hand an accessor does not exist in the object, you need to
1838 use C<get_column> instead:
1840 my $employee_count = $employee->get_column('employee_count');
1842 You can create your own accessors if required - see
1843 L<DBIx::Class::Manual::Cookbook> for details.
1845 Please note: This will NOT insert an C<AS employee_count> into the SQL
1846 statement produced, it is used for internal access only. Thus
1847 attempting to use the accessor in an C<order_by> clause or similar
1848 will fail miserably.
1850 To get around this limitation, you can supply literal SQL to your
1851 C<select> attibute that contains the C<AS alias> text, eg:
1853 select => [\'myfield AS alias']
1859 =item Value: ($rel_name | \@rel_names | \%rel_names)
1863 Contains a list of relationships that should be joined for this query. For
1866 # Get CDs by Nine Inch Nails
1867 my $rs = $schema->resultset('CD')->search(
1868 { 'artist.name' => 'Nine Inch Nails' },
1869 { join => 'artist' }
1872 Can also contain a hash reference to refer to the other relation's relations.
1875 package MyApp::Schema::Track;
1876 use base qw/DBIx::Class/;
1877 __PACKAGE__->table('track');
1878 __PACKAGE__->add_columns(qw/trackid cd position title/);
1879 __PACKAGE__->set_primary_key('trackid');
1880 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
1883 # In your application
1884 my $rs = $schema->resultset('Artist')->search(
1885 { 'track.title' => 'Teardrop' },
1887 join => { cd => 'track' },
1888 order_by => 'artist.name',
1892 You need to use the relationship (not the table) name in conditions,
1893 because they are aliased as such. The current table is aliased as "me", so
1894 you need to use me.column_name in order to avoid ambiguity. For example:
1896 # Get CDs from 1984 with a 'Foo' track
1897 my $rs = $schema->resultset('CD')->search(
1900 'tracks.name' => 'Foo'
1902 { join => 'tracks' }
1905 If the same join is supplied twice, it will be aliased to <rel>_2 (and
1906 similarly for a third time). For e.g.
1908 my $rs = $schema->resultset('Artist')->search({
1909 'cds.title' => 'Down to Earth',
1910 'cds_2.title' => 'Popular',
1912 join => [ qw/cds cds/ ],
1915 will return a set of all artists that have both a cd with title 'Down
1916 to Earth' and a cd with title 'Popular'.
1918 If you want to fetch related objects from other tables as well, see C<prefetch>
1925 =item Value: ($rel_name | \@rel_names | \%rel_names)
1929 Contains one or more relationships that should be fetched along with the main
1930 query (when they are accessed afterwards they will have already been
1931 "prefetched"). This is useful for when you know you will need the related
1932 objects, because it saves at least one query:
1934 my $rs = $schema->resultset('Tag')->search(
1943 The initial search results in SQL like the following:
1945 SELECT tag.*, cd.*, artist.* FROM tag
1946 JOIN cd ON tag.cd = cd.cdid
1947 JOIN artist ON cd.artist = artist.artistid
1949 L<DBIx::Class> has no need to go back to the database when we access the
1950 C<cd> or C<artist> relationships, which saves us two SQL statements in this
1953 Simple prefetches will be joined automatically, so there is no need
1954 for a C<join> attribute in the above search. If you're prefetching to
1955 depth (e.g. { cd => { artist => 'label' } or similar), you'll need to
1956 specify the join as well.
1958 C<prefetch> can be used with the following relationship types: C<belongs_to>,
1959 C<has_one> (or if you're using C<add_relationship>, any relationship declared
1960 with an accessor type of 'single' or 'filter').
1970 Makes the resultset paged and specifies the page to retrieve. Effectively
1971 identical to creating a non-pages resultset and then calling ->page($page)
1974 If L<rows> attribute is not specified it defualts to 10 rows per page.
1984 Specifes the maximum number of rows for direct retrieval or the number of
1985 rows per page if the page attribute or method is used.
1991 =item Value: $offset
1995 Specifies the (zero-based) row number for the first row to be returned, or the
1996 of the first row of the first page if paging is used.
2002 =item Value: \@columns
2006 A arrayref of columns to group by. Can include columns of joined tables.
2008 group_by => [qw/ column1 column2 ... /]
2014 =item Value: $condition
2018 HAVING is a select statement attribute that is applied between GROUP BY and
2019 ORDER BY. It is applied to the after the grouping calculations have been
2022 having => { 'count(employee)' => { '>=', 100 } }
2028 =item Value: (0 | 1)
2032 Set to 1 to group by all columns.
2038 Adds to the WHERE clause.
2040 # only return rows WHERE deleted IS NULL for all searches
2041 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
2043 Can be overridden by passing C<{ where => undef }> as an attribute
2050 Set to 1 to cache search results. This prevents extra SQL queries if you
2051 revisit rows in your ResultSet:
2053 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
2055 while( my $artist = $resultset->next ) {
2059 $rs->first; # without cache, this would issue a query
2061 By default, searches are not cached.
2063 For more examples of using these attributes, see
2064 L<DBIx::Class::Manual::Cookbook>.
2070 =item Value: \@from_clause
2074 The C<from> attribute gives you manual control over the C<FROM> clause of SQL
2075 statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
2078 NOTE: Use this on your own risk. This allows you to shoot off your foot!
2080 C<join> will usually do what you need and it is strongly recommended that you
2081 avoid using C<from> unless you cannot achieve the desired result using C<join>.
2082 And we really do mean "cannot", not just tried and failed. Attempting to use
2083 this because you're having problems with C<join> is like trying to use x86
2084 ASM because you've got a syntax error in your C. Trust us on this.
2086 Now, if you're still really, really sure you need to use this (and if you're
2087 not 100% sure, ask the mailing list first), here's an explanation of how this
2090 The syntax is as follows -
2093 { <alias1> => <table1> },
2095 { <alias2> => <table2>, -join_type => 'inner|left|right' },
2096 [], # nested JOIN (optional)
2097 { <table1.column1> => <table2.column2>, ... (more conditions) },
2099 # More of the above [ ] may follow for additional joins
2106 ON <table1.column1> = <table2.column2>
2107 <more joins may follow>
2109 An easy way to follow the examples below is to remember the following:
2111 Anything inside "[]" is a JOIN
2112 Anything inside "{}" is a condition for the enclosing JOIN
2114 The following examples utilize a "person" table in a family tree application.
2115 In order to express parent->child relationships, this table is self-joined:
2117 # Person->belongs_to('father' => 'Person');
2118 # Person->belongs_to('mother' => 'Person');
2120 C<from> can be used to nest joins. Here we return all children with a father,
2121 then search against all mothers of those children:
2123 $rs = $schema->resultset('Person')->search(
2126 alias => 'mother', # alias columns in accordance with "from"
2128 { mother => 'person' },
2131 { child => 'person' },
2133 { father => 'person' },
2134 { 'father.person_id' => 'child.father_id' }
2137 { 'mother.person_id' => 'child.mother_id' }
2144 # SELECT mother.* FROM person mother
2147 # JOIN person father
2148 # ON ( father.person_id = child.father_id )
2150 # ON ( mother.person_id = child.mother_id )
2152 The type of any join can be controlled manually. To search against only people
2153 with a father in the person table, we could explicitly use C<INNER JOIN>:
2155 $rs = $schema->resultset('Person')->search(
2158 alias => 'child', # alias columns in accordance with "from"
2160 { child => 'person' },
2162 { father => 'person', -join_type => 'inner' },
2163 { 'father.id' => 'child.father_id' }
2170 # SELECT child.* FROM person child
2171 # INNER JOIN person father ON child.father_id = father.id