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};
175 my $new_attrs = { %{$our_attrs}, %{$attrs} };
177 # merge new attrs into inherited
178 foreach my $key (qw/join prefetch/) {
179 next unless exists $attrs->{$key};
180 $new_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key});
185 (@_ == 1 || ref $_[0] eq "HASH")
189 ? $self->throw_exception("Odd number of arguments to search")
196 if (defined $where) {
197 $new_attrs->{where} = (
198 defined $new_attrs->{where}
201 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
202 } $where, $new_attrs->{where}
208 if (defined $having) {
209 $new_attrs->{having} = (
210 defined $new_attrs->{having}
213 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
214 } $having, $new_attrs->{having}
220 my $rs = (ref $self)->new($self->result_source, $new_attrs);
222 $rs->set_cache($rows);
227 =head2 search_literal
231 =item Arguments: $sql_fragment, @bind_values
233 =item Return Value: $resultset (scalar context), @row_objs (list context)
237 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
238 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
240 Pass a literal chunk of SQL to be added to the conditional part of the
246 my ($self, $cond, @vals) = @_;
247 my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {});
248 $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ];
249 return $self->search(\$cond, $attrs);
256 =item Arguments: @values | \%cols, \%attrs?
258 =item Return Value: $row_object
262 Finds a row based on its primary key or unique constraint. For example, to find
263 a row by its primary key:
265 my $cd = $schema->resultset('CD')->find(5);
267 You can also find a row by a specific unique constraint using the C<key>
268 attribute. For example:
270 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
271 key => 'cd_artist_title'
274 Additionally, you can specify the columns explicitly by name:
276 my $cd = $schema->resultset('CD')->find(
278 artist => 'Massive Attack',
279 title => 'Mezzanine',
281 { key => 'cd_artist_title' }
284 If the C<key> is specified as C<primary>, it searches only on the primary key.
286 If no C<key> is specified, it searches on all unique constraints defined on the
287 source, including the primary key.
289 If your table does not have a primary key, you B<must> provide a value for the
290 C<key> attribute matching one of the unique constraints on the source.
292 See also L</find_or_create> and L</update_or_create>. For information on how to
293 declare unique constraints, see
294 L<DBIx::Class::ResultSource/add_unique_constraint>.
300 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
302 # Default to the primary key, but allow a specific key
303 my @cols = exists $attrs->{key}
304 ? $self->result_source->unique_constraint_columns($attrs->{key})
305 : $self->result_source->primary_columns;
306 $self->throw_exception(
307 "Can't find unless a primary key is defined or unique constraint is specified"
310 # Parse out a hashref from input
312 if (ref $_[0] eq 'HASH') {
313 $input_query = { %{$_[0]} };
315 elsif (@_ == @cols) {
317 @{$input_query}{@cols} = @_;
320 # Compatibility: Allow e.g. find(id => $value)
321 carp "Find by key => value deprecated; please use a hashref instead";
325 my @unique_queries = $self->_unique_queries($input_query, $attrs);
327 # Build the final query: Default to the disjunction of the unique queries,
328 # but allow the input query in case the ResultSet defines the query or the
329 # user is abusing find
330 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
331 my $query = @unique_queries
332 ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
333 : $self->_add_alias($input_query, $alias);
337 my $rs = $self->search($query, $attrs);
338 return keys %{$rs->_resolved_attrs->{collapse}} ? $rs->next : $rs->single;
341 return keys %{$self->_resolved_attrs->{collapse}}
342 ? $self->search($query)->next
343 : $self->single($query);
349 # Add the specified alias to the specified query hash. A copy is made so the
350 # original query is not modified.
353 my ($self, $query, $alias) = @_;
355 my %aliased = %$query;
356 foreach my $col (grep { ! m/\./ } keys %aliased) {
357 $aliased{"$alias.$col"} = delete $aliased{$col};
365 # Build a list of queries which satisfy unique constraints.
367 sub _unique_queries {
368 my ($self, $query, $attrs) = @_;
370 my @constraint_names = exists $attrs->{key}
372 : $self->result_source->unique_constraint_names;
375 foreach my $name (@constraint_names) {
376 my @unique_cols = $self->result_source->unique_constraint_columns($name);
377 my $unique_query = $self->_build_unique_query($query, \@unique_cols);
379 my $num_query = scalar keys %$unique_query;
380 next unless $num_query;
382 # XXX: Assuming quite a bit about $self->{attrs}{where}
383 my $num_cols = scalar @unique_cols;
384 my $num_where = exists $self->{attrs}{where}
385 ? scalar keys %{ $self->{attrs}{where} }
387 push @unique_queries, $unique_query
388 if $num_query + $num_where == $num_cols;
391 return @unique_queries;
394 # _build_unique_query
396 # Constrain the specified query hash based on the specified column names.
398 sub _build_unique_query {
399 my ($self, $query, $unique_cols) = @_;
402 map { $_ => $query->{$_} }
403 grep { exists $query->{$_} }
408 =head2 search_related
412 =item Arguments: $rel, $cond, \%attrs?
414 =item Return Value: $new_resultset
418 $new_rs = $cd_rs->search_related('artist', {
422 Searches the specified relationship, optionally specifying a condition and
423 attributes for matching records. See L</ATTRIBUTES> for more information.
428 return shift->related_resultset(shift)->search(@_);
435 =item Arguments: none
437 =item Return Value: $cursor
441 Returns a storage-driven cursor to the given resultset. See
442 L<DBIx::Class::Cursor> for more information.
449 my $attrs = { %{$self->_resolved_attrs} };
450 return $self->{cursor}
451 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
452 $attrs->{where},$attrs);
459 =item Arguments: $cond?
461 =item Return Value: $row_object?
465 my $cd = $schema->resultset('CD')->single({ year => 2001 });
467 Inflates the first result without creating a cursor if the resultset has
468 any records in it; if not returns nothing. Used by L</find> as an optimisation.
470 Can optionally take an additional condition *only* - this is a fast-code-path
471 method; if you need to add extra joins or similar call ->search and then
472 ->single without a condition on the $rs returned from that.
477 my ($self, $where) = @_;
478 my $attrs = { %{$self->_resolved_attrs} };
480 if (defined $attrs->{where}) {
483 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
484 $where, delete $attrs->{where} ]
487 $attrs->{where} = $where;
491 # XXX: Disabled since it doesn't infer uniqueness in all cases
492 # unless ($self->_is_unique_query($attrs->{where})) {
493 # carp "Query not guaranteed to return a single row"
494 # . "; please declare your unique constraints or use search instead";
497 my @data = $self->result_source->storage->select_single(
498 $attrs->{from}, $attrs->{select},
499 $attrs->{where}, $attrs
502 return (@data ? $self->_construct_object(@data) : ());
507 # Try to determine if the specified query is guaranteed to be unique, based on
508 # the declared unique constraints.
510 sub _is_unique_query {
511 my ($self, $query) = @_;
513 my $collapsed = $self->_collapse_query($query);
514 my $alias = $self->{attrs}{alias};
516 foreach my $name ($self->result_source->unique_constraint_names) {
517 my @unique_cols = map {
519 } $self->result_source->unique_constraint_columns($name);
521 # Count the values for each unique column
522 my %seen = map { $_ => 0 } @unique_cols;
524 foreach my $key (keys %$collapsed) {
525 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
526 next unless exists $seen{$aliased}; # Additional constraints are okay
527 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
530 # If we get 0 or more than 1 value for a column, it's not necessarily unique
531 return 1 unless grep { $_ != 1 } values %seen;
539 # Recursively collapse the query, accumulating values for each column.
541 sub _collapse_query {
542 my ($self, $query, $collapsed) = @_;
546 if (ref $query eq 'ARRAY') {
547 foreach my $subquery (@$query) {
548 next unless ref $subquery; # -or
549 # warn "ARRAY: " . Dumper $subquery;
550 $collapsed = $self->_collapse_query($subquery, $collapsed);
553 elsif (ref $query eq 'HASH') {
554 if (keys %$query and (keys %$query)[0] eq '-and') {
555 foreach my $subquery (@{$query->{-and}}) {
556 # warn "HASH: " . Dumper $subquery;
557 $collapsed = $self->_collapse_query($subquery, $collapsed);
561 # warn "LEAF: " . Dumper $query;
562 foreach my $col (keys %$query) {
563 my $value = $query->{$col};
564 $collapsed->{$col}{$value}++;
576 =item Arguments: $cond?
578 =item Return Value: $resultsetcolumn
582 my $max_length = $rs->get_column('length')->max;
584 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
589 my ($self, $column) = @_;
590 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
598 =item Arguments: $cond, \%attrs?
600 =item Return Value: $resultset (scalar context), @row_objs (list context)
604 # WHERE title LIKE '%blue%'
605 $cd_rs = $rs->search_like({ title => '%blue%'});
607 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
608 that this is simply a convenience method. You most likely want to use
609 L</search> with specific operators.
611 For more information, see L<DBIx::Class::Manual::Cookbook>.
617 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
618 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
619 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
620 return $class->search($query, { %$attrs });
627 =item Arguments: $first, $last
629 =item Return Value: $resultset (scalar context), @row_objs (list context)
633 Returns a resultset or object list representing a subset of elements from the
634 resultset slice is called on. Indexes are from 0, i.e., to get the first
637 my ($one, $two, $three) = $rs->slice(0, 2);
642 my ($self, $min, $max) = @_;
643 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
644 $attrs->{offset} = $self->{attrs}{offset} || 0;
645 $attrs->{offset} += $min;
646 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
647 return $self->search(undef(), $attrs);
648 #my $slice = (ref $self)->new($self->result_source, $attrs);
649 #return (wantarray ? $slice->all : $slice);
656 =item Arguments: none
658 =item Return Value: $result?
662 Returns the next element in the resultset (C<undef> is there is none).
664 Can be used to efficiently iterate over records in the resultset:
666 my $rs = $schema->resultset('CD')->search;
667 while (my $cd = $rs->next) {
671 Note that you need to store the resultset object, and call C<next> on it.
672 Calling C<< resultset('Table')->next >> repeatedly will always return the
673 first record from the resultset.
679 if (my $cache = $self->get_cache) {
680 $self->{all_cache_position} ||= 0;
681 return $cache->[$self->{all_cache_position}++];
683 if ($self->{attrs}{cache}) {
684 $self->{all_cache_position} = 1;
685 return ($self->all)[0];
688 exists $self->{stashed_row}
689 ? @{delete $self->{stashed_row}}
690 : $self->cursor->next
692 return unless (@row);
693 return $self->_construct_object(@row);
696 sub _construct_object {
697 my ($self, @row) = @_;
698 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row);
699 my $new = $self->result_class->inflate_result($self->result_source, @$info);
700 $new = $self->{_attrs}{record_filter}->($new)
701 if exists $self->{_attrs}{record_filter};
705 sub _collapse_result {
706 my ($self, $as, $row, $prefix) = @_;
711 foreach my $this_as (@$as) {
712 my $val = shift @copy;
713 if (defined $prefix) {
714 if ($this_as =~ m/^\Q${prefix}.\E(.+)$/) {
716 $remain =~ /^(?:(.*)\.)?([^.]+)$/;
717 $const{$1||''}{$2} = $val;
720 $this_as =~ /^(?:(.*)\.)?([^.]+)$/;
721 $const{$1||''}{$2} = $val;
725 my $alias = $self->{attrs}{alias};
726 my $info = [ {}, {} ];
727 foreach my $key (keys %const) {
728 if (length $key && $key ne $alias) {
730 my @parts = split(/\./, $key);
731 foreach my $p (@parts) {
732 $target = $target->[1]->{$p} ||= [];
734 $target->[0] = $const{$key};
736 $info->[0] = $const{$key};
741 if (defined $prefix) {
743 m/^\Q${prefix}.\E(.+)$/ ? ($1) : ()
744 } keys %{$self->{_attrs}{collapse}}
746 @collapse = keys %{$self->{_attrs}{collapse}};
750 my ($c) = sort { length $a <=> length $b } @collapse;
752 foreach my $p (split(/\./, $c)) {
753 $target = $target->[1]->{$p} ||= [];
755 my $c_prefix = (defined($prefix) ? "${prefix}.${c}" : $c);
756 my @co_key = @{$self->{_attrs}{collapse}{$c_prefix}};
757 my $tree = $self->_collapse_result($as, $row, $c_prefix);
758 my %co_check = map { ($_, $tree->[0]->{$_}); } @co_key;
764 !defined($tree->[0]->{$_}) || $co_check{$_} ne $tree->[0]->{$_}
769 last unless (@raw = $self->cursor->next);
770 $row = $self->{stashed_row} = \@raw;
771 $tree = $self->_collapse_result($as, $row, $c_prefix);
773 @$target = (@final ? @final : [ {}, {} ]);
774 # single empty result to indicate an empty prefetched has_many
777 #print "final info: " . Dumper($info);
785 =item Arguments: $result_source?
787 =item Return Value: $result_source
791 An accessor for the primary ResultSource object from which this ResultSet
798 =item Arguments: $result_class?
800 =item Return Value: $result_class
804 An accessor for the class to use when creating row objects. Defaults to
805 C<< result_source->result_class >> - which in most cases is the name of the
806 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
815 =item Arguments: $cond, \%attrs??
817 =item Return Value: $count
821 Performs an SQL C<COUNT> with the same query as the resultset was built
822 with to find the number of elements. If passed arguments, does a search
823 on the resultset and counts the results of that.
825 Note: When using C<count> with C<group_by>, L<DBIX::Class> emulates C<GROUP BY>
826 using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do
827 not support C<DISTINCT> with multiple columns. If you are using such a
828 database, you should only use columns from the main table in your C<group_by>
835 return $self->search(@_)->count if @_ and defined $_[0];
836 return scalar @{ $self->get_cache } if $self->get_cache;
837 my $count = $self->_count;
838 return 0 unless $count;
840 $count -= $self->{attrs}{offset} if $self->{attrs}{offset};
841 $count = $self->{attrs}{rows} if
842 $self->{attrs}{rows} and $self->{attrs}{rows} < $count;
846 sub _count { # Separated out so pager can get the full count
848 my $select = { count => '*' };
850 my $attrs = { %{$self->_resolved_attrs} };
851 if (my $group_by = delete $attrs->{group_by}) {
852 delete $attrs->{having};
853 my @distinct = (ref $group_by ? @$group_by : ($group_by));
854 # todo: try CONCAT for multi-column pk
855 my @pk = $self->result_source->primary_columns;
857 my $alias = $attrs->{alias};
858 foreach my $column (@distinct) {
859 if ($column =~ qr/^(?:\Q${alias}.\E)?$pk[0]$/) {
860 @distinct = ($column);
866 $select = { count => { distinct => \@distinct } };
869 $attrs->{select} = $select;
870 $attrs->{as} = [qw/count/];
872 # offset, order by and page are not needed to count. record_filter is cdbi
873 delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/;
875 my $tmp_rs = (ref $self)->new($self->result_source, $attrs);
876 my ($count) = $tmp_rs->cursor->next;
884 =item Arguments: $sql_fragment, @bind_values
886 =item Return Value: $count
890 Counts the results in a literal query. Equivalent to calling L</search_literal>
891 with the passed arguments, then L</count>.
895 sub count_literal { shift->search_literal(@_)->count; }
901 =item Arguments: none
903 =item Return Value: @objects
907 Returns all elements in the resultset. Called implicitly if the resultset
908 is returned in list context.
914 return @{ $self->get_cache } if $self->get_cache;
918 # TODO: don't call resolve here
919 if (keys %{$self->_resolved_attrs->{collapse}}) {
920 # if ($self->{attrs}{prefetch}) {
921 # Using $self->cursor->all is really just an optimisation.
922 # If we're collapsing has_many prefetches it probably makes
923 # very little difference, and this is cleaner than hacking
924 # _construct_object to survive the approach
925 my @row = $self->cursor->next;
927 push(@obj, $self->_construct_object(@row));
928 @row = (exists $self->{stashed_row}
929 ? @{delete $self->{stashed_row}}
930 : $self->cursor->next);
933 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
936 $self->set_cache(\@obj) if $self->{attrs}{cache};
944 =item Arguments: none
946 =item Return Value: $self
950 Resets the resultset's cursor, so you can iterate through the elements again.
956 delete $self->{_attrs} if exists $self->{_attrs};
957 $self->{all_cache_position} = 0;
958 $self->cursor->reset;
966 =item Arguments: none
968 =item Return Value: $object?
972 Resets the resultset and returns an object for the first result (if the
973 resultset returns anything).
978 return $_[0]->reset->next;
981 # _cond_for_update_delete
983 # update/delete require the condition to be modified to handle
984 # the differing SQL syntax available. This transforms the $self->{cond}
985 # appropriately, returning the new condition.
987 sub _cond_for_update_delete {
991 # No-op. No condition, we're updating/deleting everything
992 return $cond unless ref $self->{cond};
994 if (ref $self->{cond} eq 'ARRAY') {
998 foreach my $key (keys %{$_}) {
1000 $hash{$1} = $_->{$key};
1006 elsif (ref $self->{cond} eq 'HASH') {
1007 if ((keys %{$self->{cond}})[0] eq '-and') {
1010 my @cond = @{$self->{cond}{-and}};
1011 for (my $i = 0; $i < @cond; $i++) {
1012 my $entry = $cond[$i];
1015 if (ref $entry eq 'HASH') {
1016 foreach my $key (keys %{$entry}) {
1018 $hash{$1} = $entry->{$key};
1022 $entry =~ /([^.]+)$/;
1023 $hash{$1} = $cond[++$i];
1026 push @{$cond->{-and}}, \%hash;
1030 foreach my $key (keys %{$self->{cond}}) {
1032 $cond->{$1} = $self->{cond}{$key};
1037 $self->throw_exception(
1038 "Can't update/delete on resultset with condition unless hash or array"
1050 =item Arguments: \%values
1052 =item Return Value: $storage_rv
1056 Sets the specified columns in the resultset to the supplied values in a
1057 single query. Return value will be true if the update succeeded or false
1058 if no records were updated; exact type of success value is storage-dependent.
1063 my ($self, $values) = @_;
1064 $self->throw_exception("Values for update must be a hash")
1065 unless ref $values eq 'HASH';
1067 my $cond = $self->_cond_for_update_delete;
1069 return $self->result_source->storage->update(
1070 $self->result_source->from, $values, $cond
1078 =item Arguments: \%values
1080 =item Return Value: 1
1084 Fetches all objects and updates them one at a time. Note that C<update_all>
1085 will run DBIC cascade triggers, while L</update> will not.
1090 my ($self, $values) = @_;
1091 $self->throw_exception("Values for update must be a hash")
1092 unless ref $values eq 'HASH';
1093 foreach my $obj ($self->all) {
1094 $obj->set_columns($values)->update;
1103 =item Arguments: none
1105 =item Return Value: 1
1109 Deletes the contents of the resultset from its result source. Note that this
1110 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1118 my $cond = $self->_cond_for_update_delete;
1120 $self->result_source->storage->delete($self->result_source->from, $cond);
1128 =item Arguments: none
1130 =item Return Value: 1
1134 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1135 will run DBIC cascade triggers, while L</delete> will not.
1141 $_->delete for $self->all;
1149 =item Arguments: none
1151 =item Return Value: $pager
1155 Return Value a L<Data::Page> object for the current resultset. Only makes
1156 sense for queries with a C<page> attribute.
1162 my $attrs = $self->{attrs};
1163 $self->throw_exception("Can't create pager for non-paged rs")
1164 unless $self->{attrs}{page};
1165 $attrs->{rows} ||= 10;
1166 return $self->{pager} ||= Data::Page->new(
1167 $self->_count, $attrs->{rows}, $self->{attrs}{page});
1174 =item Arguments: $page_number
1176 =item Return Value: $rs
1180 Returns a resultset for the $page_number page of the resultset on which page
1181 is called, where each page contains a number of rows equal to the 'rows'
1182 attribute set on the resultset (10 by default).
1187 my ($self, $page) = @_;
1188 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1195 =item Arguments: \%vals
1197 =item Return Value: $object
1201 Creates an object in the resultset's result class and returns it.
1206 my ($self, $values) = @_;
1207 $self->throw_exception( "new_result needs a hash" )
1208 unless (ref $values eq 'HASH');
1209 $self->throw_exception(
1210 "Can't abstract implicit construct, condition not a hash"
1211 ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
1213 my $alias = $self->{attrs}{alias};
1215 %{ $self->_remove_alias($values, $alias) },
1216 %{ $self->_remove_alias($self->{cond}, $alias) },
1219 my $obj = $self->result_class->new(\%new);
1220 $obj->result_source($self->result_source) if $obj->can('result_source');
1226 # Remove the specified alias from the specified query hash. A copy is made so
1227 # the original query is not modified.
1230 my ($self, $query, $alias) = @_;
1232 my %unaliased = %{ $query || {} };
1233 foreach my $key (keys %unaliased) {
1234 $unaliased{$1} = delete $unaliased{$key}
1235 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
1245 =item Arguments: \%vals, \%attrs?
1247 =item Return Value: $object
1251 Find an existing record from this resultset. If none exists, instantiate a new
1252 result object and return it. The object will not be saved into your storage
1253 until you call L<DBIx::Class::Row/insert> on it.
1255 If you want objects to be saved immediately, use L</find_or_create> instead.
1261 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1262 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1263 my $exists = $self->find($hash, $attrs);
1264 return defined $exists ? $exists : $self->new_result($hash);
1271 =item Arguments: \%vals
1273 =item Return Value: $object
1277 Inserts a record into the resultset and returns the object representing it.
1279 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
1284 my ($self, $attrs) = @_;
1285 $self->throw_exception( "create needs a hashref" )
1286 unless ref $attrs eq 'HASH';
1287 return $self->new_result($attrs)->insert;
1290 =head2 find_or_create
1294 =item Arguments: \%vals, \%attrs?
1296 =item Return Value: $object
1300 $class->find_or_create({ key => $val, ... });
1302 Tries to find a record based on its primary key or unique constraint; if none
1303 is found, creates one and returns that instead.
1305 my $cd = $schema->resultset('CD')->find_or_create({
1307 artist => 'Massive Attack',
1308 title => 'Mezzanine',
1312 Also takes an optional C<key> attribute, to search by a specific key or unique
1313 constraint. For example:
1315 my $cd = $schema->resultset('CD')->find_or_create(
1317 artist => 'Massive Attack',
1318 title => 'Mezzanine',
1320 { key => 'cd_artist_title' }
1323 See also L</find> and L</update_or_create>. For information on how to declare
1324 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1328 sub find_or_create {
1330 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1331 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1332 my $exists = $self->find($hash, $attrs);
1333 return defined $exists ? $exists : $self->create($hash);
1336 =head2 update_or_create
1340 =item Arguments: \%col_values, { key => $unique_constraint }?
1342 =item Return Value: $object
1346 $class->update_or_create({ col => $val, ... });
1348 First, searches for an existing row matching one of the unique constraints
1349 (including the primary key) on the source of this resultset. If a row is
1350 found, updates it with the other given column values. Otherwise, creates a new
1353 Takes an optional C<key> attribute to search on a specific unique constraint.
1356 # In your application
1357 my $cd = $schema->resultset('CD')->update_or_create(
1359 artist => 'Massive Attack',
1360 title => 'Mezzanine',
1363 { key => 'cd_artist_title' }
1366 If no C<key> is specified, it searches on all unique constraints defined on the
1367 source, including the primary key.
1369 If the C<key> is specified as C<primary>, it searches only on the primary key.
1371 See also L</find> and L</find_or_create>. For information on how to declare
1372 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1376 sub update_or_create {
1378 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1379 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
1381 my $row = $self->find($cond, $attrs);
1383 $row->update($cond);
1387 return $self->create($cond);
1394 =item Arguments: none
1396 =item Return Value: \@cache_objects?
1400 Gets the contents of the cache for the resultset, if the cache is set.
1412 =item Arguments: \@cache_objects
1414 =item Return Value: \@cache_objects
1418 Sets the contents of the cache for the resultset. Expects an arrayref
1419 of objects of the same class as those produced by the resultset. Note that
1420 if the cache is set the resultset will return the cached objects rather
1421 than re-querying the database even if the cache attr is not set.
1426 my ( $self, $data ) = @_;
1427 $self->throw_exception("set_cache requires an arrayref")
1428 if defined($data) && (ref $data ne 'ARRAY');
1429 $self->{all_cache} = $data;
1436 =item Arguments: none
1438 =item Return Value: []
1442 Clears the cache for the resultset.
1447 shift->set_cache(undef);
1450 =head2 related_resultset
1454 =item Arguments: $relationship_name
1456 =item Return Value: $resultset
1460 Returns a related resultset for the supplied relationship name.
1462 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
1466 sub related_resultset {
1467 my ($self, $rel) = @_;
1469 $self->{related_resultsets} ||= {};
1470 return $self->{related_resultsets}{$rel} ||= do {
1471 my $rel_obj = $self->result_source->relationship_info($rel);
1473 $self->throw_exception(
1474 "search_related: result source '" . $self->result_source->name .
1475 "' has no such relationship $rel")
1478 my ($from,$seen) = $self->_resolve_from($rel);
1480 my $join_count = $seen->{$rel};
1481 my $alias = ($join_count > 1 ? join('_', $rel, $join_count) : $rel);
1483 $self->result_source->schema->resultset($rel_obj->{class})->search_rs(
1485 %{$self->{attrs}||{}},
1491 where => $self->{cond},
1499 my ($self, $extra_join) = @_;
1500 my $source = $self->result_source;
1501 my $attrs = $self->{attrs};
1503 my $from = $attrs->{from}
1504 || [ { $attrs->{alias} => $source->from } ];
1506 my $seen = { %{$attrs->{seen_join}||{}} };
1508 my $join = ($attrs->{join}
1509 ? [ $attrs->{join}, $extra_join ]
1513 ($join ? $source->resolve_join($join, $attrs->{alias}, $seen) : ()),
1516 return ($from,$seen);
1519 sub _resolved_attrs {
1521 return $self->{_attrs} if $self->{_attrs};
1523 my $attrs = { %{$self->{attrs}||{}} };
1524 my $source = $self->{result_source};
1525 my $alias = $attrs->{alias};
1527 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
1528 if ($attrs->{columns}) {
1529 delete $attrs->{as};
1530 } elsif (!$attrs->{select}) {
1531 $attrs->{columns} = [ $source->columns ];
1536 ? (ref $attrs->{select} eq 'ARRAY'
1537 ? [ @{$attrs->{select}} ]
1538 : [ $attrs->{select} ])
1539 : [ map { m/\./ ? $_ : "${alias}.$_" } @{delete $attrs->{columns}} ]
1543 ? (ref $attrs->{as} eq 'ARRAY'
1544 ? [ @{$attrs->{as}} ]
1546 : [ map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{$attrs->{select}} ]
1550 if ($adds = delete $attrs->{include_columns}) {
1551 $adds = [$adds] unless ref $adds eq 'ARRAY';
1552 push(@{$attrs->{select}}, @$adds);
1553 push(@{$attrs->{as}}, map { m/([^.]+)$/; $1 } @$adds);
1555 if ($adds = delete $attrs->{'+select'}) {
1556 $adds = [$adds] unless ref $adds eq 'ARRAY';
1557 push(@{$attrs->{select}},
1558 map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds);
1560 if (my $adds = delete $attrs->{'+as'}) {
1561 $adds = [$adds] unless ref $adds eq 'ARRAY';
1562 push(@{$attrs->{as}}, @$adds);
1565 $attrs->{from} ||= [ { 'me' => $source->from } ];
1567 if (exists $attrs->{join} || exists $attrs->{prefetch}) {
1568 my $join = delete $attrs->{join} || {};
1570 if (defined $attrs->{prefetch}) {
1571 $join = $self->_merge_attr(
1572 $join, $attrs->{prefetch}
1576 $attrs->{from} = # have to copy here to avoid corrupting the original
1579 $source->resolve_join($join, $alias, { %{$attrs->{seen_join}||{}} })
1583 $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct};
1584 if ($attrs->{order_by}) {
1585 $attrs->{order_by} = (ref($attrs->{order_by}) eq 'ARRAY'
1586 ? [ @{$attrs->{order_by}} ]
1587 : [ $attrs->{order_by} ]);
1589 $attrs->{order_by} = [];
1592 my $collapse = $attrs->{collapse} || {};
1593 if (my $prefetch = delete $attrs->{prefetch}) {
1594 $prefetch = $self->_merge_attr({}, $prefetch);
1596 my $seen = $attrs->{seen_join} || {};
1597 foreach my $p (ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch)) {
1598 # bring joins back to level of current class
1599 my @prefetch = $source->resolve_prefetch(
1600 $p, $alias, $seen, \@pre_order, $collapse
1602 push(@{$attrs->{select}}, map { $_->[0] } @prefetch);
1603 push(@{$attrs->{as}}, map { $_->[1] } @prefetch);
1605 push(@{$attrs->{order_by}}, @pre_order);
1607 $attrs->{collapse} = $collapse;
1609 return $self->{_attrs} = $attrs;
1613 my ($self, $a, $b) = @_;
1614 return $b unless defined($a);
1615 return $a unless defined($b);
1617 if (ref $b eq 'HASH' && ref $a eq 'HASH') {
1618 foreach my $key (keys %{$b}) {
1619 if (exists $a->{$key}) {
1620 $a->{$key} = $self->_merge_attr($a->{$key}, $b->{$key});
1622 $a->{$key} = $b->{$key};
1627 $a = [$a] unless ref $a eq 'ARRAY';
1628 $b = [$b] unless ref $b eq 'ARRAY';
1632 foreach my $x ($a, $b) {
1633 foreach my $element (@{$x}) {
1634 if (ref $element eq 'HASH') {
1635 $hash = $self->_merge_attr($hash, $element);
1636 } elsif (ref $element eq 'ARRAY') {
1637 push(@array, @{$element});
1639 push(@array, $element) unless $b == $x
1640 && grep { $_ eq $element } @array;
1645 @array = grep { !exists $hash->{$_} } @array;
1647 return keys %{$hash}
1656 =head2 throw_exception
1658 See L<DBIx::Class::Schema/throw_exception> for details.
1662 sub throw_exception {
1664 $self->result_source->schema->throw_exception(@_);
1667 # XXX: FIXME: Attributes docs need clearing up
1671 The resultset takes various attributes that modify its behavior. Here's an
1678 =item Value: ($order_by | \@order_by)
1682 Which column(s) to order the results by. This is currently passed
1683 through directly to SQL, so you can give e.g. C<year DESC> for a
1684 descending order on the column `year'.
1686 Please note that if you have quoting enabled (see
1687 L<DBIx::Class::Storage/quote_char>) you will need to do C<\'year DESC' > to
1688 specify an order. (The scalar ref causes it to be passed as raw sql to the DB,
1689 so you will need to manually quote things as appropriate.)
1695 =item Value: \@columns
1699 Shortcut to request a particular set of columns to be retrieved. Adds
1700 C<me.> onto the start of any column without a C<.> in it and sets C<select>
1701 from that, then auto-populates C<as> from C<select> as normal. (You may also
1702 use the C<cols> attribute, as in earlier versions of DBIC.)
1704 =head2 include_columns
1708 =item Value: \@columns
1712 Shortcut to include additional columns in the returned results - for example
1714 $schema->resultset('CD')->search(undef, {
1715 include_columns => ['artist.name'],
1719 would return all CDs and include a 'name' column to the information
1720 passed to object inflation
1726 =item Value: \@select_columns
1730 Indicates which columns should be selected from the storage. You can use
1731 column names, or in the case of RDBMS back ends, function or stored procedure
1734 $rs = $schema->resultset('Employee')->search(undef, {
1737 { count => 'employeeid' },
1742 When you use function/stored procedure names and do not supply an C<as>
1743 attribute, the column names returned are storage-dependent. E.g. MySQL would
1744 return a column named C<count(employeeid)> in the above example.
1750 Indicates additional columns to be selected from storage. Works the same as
1751 L<select> but adds columns to the selection.
1759 Indicates additional column names for those added via L<+select>.
1767 =item Value: \@inflation_names
1771 Indicates column names for object inflation. This is used in conjunction with
1772 C<select>, usually when C<select> contains one or more function or stored
1775 $rs = $schema->resultset('Employee')->search(undef, {
1778 { count => 'employeeid' }
1780 as => ['name', 'employee_count'],
1783 my $employee = $rs->first(); # get the first Employee
1785 If the object against which the search is performed already has an accessor
1786 matching a column name specified in C<as>, the value can be retrieved using
1787 the accessor as normal:
1789 my $name = $employee->name();
1791 If on the other hand an accessor does not exist in the object, you need to
1792 use C<get_column> instead:
1794 my $employee_count = $employee->get_column('employee_count');
1796 You can create your own accessors if required - see
1797 L<DBIx::Class::Manual::Cookbook> for details.
1799 Please note: This will NOT insert an C<AS employee_count> into the SQL
1800 statement produced, it is used for internal access only. Thus
1801 attempting to use the accessor in an C<order_by> clause or similar
1802 will fail miserably.
1804 To get around this limitation, you can supply literal SQL to your
1805 C<select> attibute that contains the C<AS alias> text, eg:
1807 select => [\'myfield AS alias']
1813 =item Value: ($rel_name | \@rel_names | \%rel_names)
1817 Contains a list of relationships that should be joined for this query. For
1820 # Get CDs by Nine Inch Nails
1821 my $rs = $schema->resultset('CD')->search(
1822 { 'artist.name' => 'Nine Inch Nails' },
1823 { join => 'artist' }
1826 Can also contain a hash reference to refer to the other relation's relations.
1829 package MyApp::Schema::Track;
1830 use base qw/DBIx::Class/;
1831 __PACKAGE__->table('track');
1832 __PACKAGE__->add_columns(qw/trackid cd position title/);
1833 __PACKAGE__->set_primary_key('trackid');
1834 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
1837 # In your application
1838 my $rs = $schema->resultset('Artist')->search(
1839 { 'track.title' => 'Teardrop' },
1841 join => { cd => 'track' },
1842 order_by => 'artist.name',
1846 You need to use the relationship (not the table) name in conditions,
1847 because they are aliased as such. The current table is aliased as "me", so
1848 you need to use me.column_name in order to avoid ambiguity. For example:
1850 # Get CDs from 1984 with a 'Foo' track
1851 my $rs = $schema->resultset('CD')->search(
1854 'tracks.name' => 'Foo'
1856 { join => 'tracks' }
1859 If the same join is supplied twice, it will be aliased to <rel>_2 (and
1860 similarly for a third time). For e.g.
1862 my $rs = $schema->resultset('Artist')->search({
1863 'cds.title' => 'Down to Earth',
1864 'cds_2.title' => 'Popular',
1866 join => [ qw/cds cds/ ],
1869 will return a set of all artists that have both a cd with title 'Down
1870 to Earth' and a cd with title 'Popular'.
1872 If you want to fetch related objects from other tables as well, see C<prefetch>
1879 =item Value: ($rel_name | \@rel_names | \%rel_names)
1883 Contains one or more relationships that should be fetched along with the main
1884 query (when they are accessed afterwards they will have already been
1885 "prefetched"). This is useful for when you know you will need the related
1886 objects, because it saves at least one query:
1888 my $rs = $schema->resultset('Tag')->search(
1897 The initial search results in SQL like the following:
1899 SELECT tag.*, cd.*, artist.* FROM tag
1900 JOIN cd ON tag.cd = cd.cdid
1901 JOIN artist ON cd.artist = artist.artistid
1903 L<DBIx::Class> has no need to go back to the database when we access the
1904 C<cd> or C<artist> relationships, which saves us two SQL statements in this
1907 Simple prefetches will be joined automatically, so there is no need
1908 for a C<join> attribute in the above search. If you're prefetching to
1909 depth (e.g. { cd => { artist => 'label' } or similar), you'll need to
1910 specify the join as well.
1912 C<prefetch> can be used with the following relationship types: C<belongs_to>,
1913 C<has_one> (or if you're using C<add_relationship>, any relationship declared
1914 with an accessor type of 'single' or 'filter').
1924 Makes the resultset paged and specifies the page to retrieve. Effectively
1925 identical to creating a non-pages resultset and then calling ->page($page)
1928 If L<rows> attribute is not specified it defualts to 10 rows per page.
1938 Specifes the maximum number of rows for direct retrieval or the number of
1939 rows per page if the page attribute or method is used.
1945 =item Value: $offset
1949 Specifies the (zero-based) row number for the first row to be returned, or the
1950 of the first row of the first page if paging is used.
1956 =item Value: \@columns
1960 A arrayref of columns to group by. Can include columns of joined tables.
1962 group_by => [qw/ column1 column2 ... /]
1968 =item Value: $condition
1972 HAVING is a select statement attribute that is applied between GROUP BY and
1973 ORDER BY. It is applied to the after the grouping calculations have been
1976 having => { 'count(employee)' => { '>=', 100 } }
1982 =item Value: (0 | 1)
1986 Set to 1 to group by all columns.
1992 Adds to the WHERE clause.
1994 # only return rows WHERE deleted IS NULL for all searches
1995 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
1997 Can be overridden by passing C<{ where => undef }> as an attribute
2004 Set to 1 to cache search results. This prevents extra SQL queries if you
2005 revisit rows in your ResultSet:
2007 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
2009 while( my $artist = $resultset->next ) {
2013 $rs->first; # without cache, this would issue a query
2015 By default, searches are not cached.
2017 For more examples of using these attributes, see
2018 L<DBIx::Class::Manual::Cookbook>.
2024 =item Value: \@from_clause
2028 The C<from> attribute gives you manual control over the C<FROM> clause of SQL
2029 statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
2032 NOTE: Use this on your own risk. This allows you to shoot off your foot!
2034 C<join> will usually do what you need and it is strongly recommended that you
2035 avoid using C<from> unless you cannot achieve the desired result using C<join>.
2036 And we really do mean "cannot", not just tried and failed. Attempting to use
2037 this because you're having problems with C<join> is like trying to use x86
2038 ASM because you've got a syntax error in your C. Trust us on this.
2040 Now, if you're still really, really sure you need to use this (and if you're
2041 not 100% sure, ask the mailing list first), here's an explanation of how this
2044 The syntax is as follows -
2047 { <alias1> => <table1> },
2049 { <alias2> => <table2>, -join_type => 'inner|left|right' },
2050 [], # nested JOIN (optional)
2051 { <table1.column1> => <table2.column2>, ... (more conditions) },
2053 # More of the above [ ] may follow for additional joins
2060 ON <table1.column1> = <table2.column2>
2061 <more joins may follow>
2063 An easy way to follow the examples below is to remember the following:
2065 Anything inside "[]" is a JOIN
2066 Anything inside "{}" is a condition for the enclosing JOIN
2068 The following examples utilize a "person" table in a family tree application.
2069 In order to express parent->child relationships, this table is self-joined:
2071 # Person->belongs_to('father' => 'Person');
2072 # Person->belongs_to('mother' => 'Person');
2074 C<from> can be used to nest joins. Here we return all children with a father,
2075 then search against all mothers of those children:
2077 $rs = $schema->resultset('Person')->search(
2080 alias => 'mother', # alias columns in accordance with "from"
2082 { mother => 'person' },
2085 { child => 'person' },
2087 { father => 'person' },
2088 { 'father.person_id' => 'child.father_id' }
2091 { 'mother.person_id' => 'child.mother_id' }
2098 # SELECT mother.* FROM person mother
2101 # JOIN person father
2102 # ON ( father.person_id = child.father_id )
2104 # ON ( mother.person_id = child.mother_id )
2106 The type of any join can be controlled manually. To search against only people
2107 with a father in the person table, we could explicitly use C<INNER JOIN>:
2109 $rs = $schema->resultset('Person')->search(
2112 alias => 'child', # alias columns in accordance with "from"
2114 { child => 'person' },
2116 { father => 'person', -join_type => 'inner' },
2117 { 'father.id' => 'child.father_id' }
2124 # SELECT child.* FROM person child
2125 # INNER JOIN person father ON child.father_id = father.id