1 package DBIx::Class::ResultSet;
9 use Carp::Clan qw/^DBIx::Class/;
13 use Scalar::Util qw/weaken/;
15 use DBIx::Class::ResultSetColumn;
16 use base qw/DBIx::Class/;
17 __PACKAGE__->load_components(qw/AccessorGroup/);
18 __PACKAGE__->mk_group_accessors('simple' => qw/result_source result_class/);
22 DBIx::Class::ResultSet - Responsible for fetching and creating resultset.
26 my $rs = $schema->resultset('User')->search(registered => 1);
27 my @rows = $schema->resultset('CD')->search(year => 2005);
31 The resultset is also known as an iterator. It is responsible for handling
32 queries that may return an arbitrary number of rows, e.g. via L</search>
33 or a C<has_many> relationship.
35 In the examples below, the following table classes are used:
37 package MyApp::Schema::Artist;
38 use base qw/DBIx::Class/;
39 __PACKAGE__->load_components(qw/Core/);
40 __PACKAGE__->table('artist');
41 __PACKAGE__->add_columns(qw/artistid name/);
42 __PACKAGE__->set_primary_key('artistid');
43 __PACKAGE__->has_many(cds => 'MyApp::Schema::CD');
46 package MyApp::Schema::CD;
47 use base qw/DBIx::Class/;
48 __PACKAGE__->load_components(qw/Core/);
49 __PACKAGE__->table('cd');
50 __PACKAGE__->add_columns(qw/cdid artist title year/);
51 __PACKAGE__->set_primary_key('cdid');
52 __PACKAGE__->belongs_to(artist => 'MyApp::Schema::Artist');
61 =item Arguments: $source, \%$attrs
63 =item Return Value: $rs
67 The resultset constructor. Takes a source object (usually a
68 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
69 L</ATTRIBUTES> below). Does not perform any queries -- these are
70 executed as needed by the other methods.
72 Generally you won't need to construct a resultset manually. You'll
73 automatically get one from e.g. a L</search> called in scalar context:
75 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
77 IMPORTANT: If called on an object, proxies to new_result instead so
79 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
81 will return a CD object, not a ResultSet.
87 return $class->new_result(@_) if ref $class;
89 my ($source, $attrs) = @_;
93 $attrs->{rows} ||= 10;
94 $attrs->{offset} ||= 0;
95 $attrs->{offset} += ($attrs->{rows} * ($attrs->{page} - 1));
98 $attrs->{alias} ||= 'me';
101 result_source => $source,
102 result_class => $attrs->{result_class} || $source->result_class,
103 cond => $attrs->{where},
104 # from => $attrs->{from},
105 # collapse => $collapse,
107 page => delete $attrs->{page},
117 =item Arguments: $cond, \%attrs?
119 =item Return Value: $resultset (scalar context), @row_objs (list context)
123 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
124 my $new_rs = $cd_rs->search({ year => 2005 });
126 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
127 # year = 2005 OR year = 2004
129 If you need to pass in additional attributes but no additional condition,
130 call it as C<search(undef, \%attrs)>.
132 # "SELECT name, artistid FROM $artist_table"
133 my @all_artists = $schema->resultset('Artist')->search(undef, {
134 columns => [qw/name artistid/],
141 my $rs = $self->search_rs( @_ );
142 return (wantarray ? $rs->all : $rs);
149 =item Arguments: $cond, \%attrs?
151 =item Return Value: $resultset
155 This method does the same exact thing as search() except it will
156 always return a resultset, even in list context.
164 $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
165 my $our_attrs = ($attrs->{_parent_attrs}) ? { %{$attrs->{_parent_attrs}} } : { %{$self->{attrs}} };
166 my $having = delete $our_attrs->{having};
168 # XXX this is getting messy
169 if ($attrs->{_live_join_stack}) {
170 my $live_join = $attrs->{_live_join_stack};
171 foreach (reverse @{$live_join}) {
172 $attrs->{_live_join_h} = (defined $attrs->{_live_join_h}) ? { $_ => $attrs->{_live_join_h} } : $_;
176 # merge new attrs into old
177 foreach my $key (qw/join prefetch/) {
178 next unless (exists $attrs->{$key});
179 if ($attrs->{_live_join_stack} || $our_attrs->{_live_join_stack}) {
180 my $live_join = $attrs->{_live_join_stack} || $our_attrs->{_live_join_stack};
181 foreach (reverse @{$live_join}) {
182 $attrs->{$key} = { $_ => $attrs->{$key} };
186 if (exists $our_attrs->{$key}) {
187 $our_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key});
189 $our_attrs->{$key} = $attrs->{$key};
191 delete $attrs->{$key};
194 $our_attrs->{join} = $self->_merge_attr($our_attrs->{join}, $attrs->{_live_join_h}, 1) if ($attrs->{_live_join_h});
196 if (exists $our_attrs->{prefetch}) {
197 $our_attrs->{join} = $self->_merge_attr($our_attrs->{join}, $our_attrs->{prefetch}, 1);
200 my $new_attrs = { %{$our_attrs}, %{$attrs} };
202 ? ((@_ == 1 || ref $_[0] eq "HASH")
205 ? $self->throw_exception(
206 "Odd number of arguments to search")
209 if (defined $where) {
210 $new_attrs->{where} = (defined $new_attrs->{where}
212 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
213 $where, $new_attrs->{where} ] }
217 if (defined $having) {
218 $new_attrs->{having} = (defined $new_attrs->{having}
220 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
221 $having, $new_attrs->{having} ] }
225 my $rs = (ref $self)->new($self->result_source, $new_attrs);
226 $rs->{_parent_rs} = $self->{_parent_rs} if ($self->{_parent_rs}); #XXX - hack to pass through parent of related resultsets
228 unless (@_) { # no search, effectively just a clone
229 my $rows = $self->get_cache;
231 $rs->set_cache($rows);
238 =head2 search_literal
242 =item Arguments: $sql_fragment, @bind_values
244 =item Return Value: $resultset (scalar context), @row_objs (list context)
248 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
249 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
251 Pass a literal chunk of SQL to be added to the conditional part of the
257 my ($self, $cond, @vals) = @_;
258 my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {});
259 $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ];
260 return $self->search(\$cond, $attrs);
267 =item Arguments: @values | \%cols, \%attrs?
269 =item Return Value: $row_object
273 Finds a row based on its primary key or unique constraint. For example, to find
274 a row by its primary key:
276 my $cd = $schema->resultset('CD')->find(5);
278 You can also find a row by a specific unique constraint using the C<key>
279 attribute. For example:
281 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', { key => 'cd_artist_title' });
283 Additionally, you can specify the columns explicitly by name:
285 my $cd = $schema->resultset('CD')->find(
287 artist => 'Massive Attack',
288 title => 'Mezzanine',
290 { key => 'cd_artist_title' }
293 If the C<key> is specified as C<primary>, it searches only on the primary key.
295 If no C<key> is specified, it searches on all unique constraints defined on the
296 source, including the primary key.
298 See also L</find_or_create> and L</update_or_create>. For information on how to
299 declare unique constraints, see
300 L<DBIx::Class::ResultSource/add_unique_constraint>.
306 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
308 # Default to the primary key, but allow a specific key
309 my @cols = exists $attrs->{key}
310 ? $self->result_source->unique_constraint_columns($attrs->{key})
311 : $self->result_source->primary_columns;
312 $self->throw_exception(
313 "Can't find unless a primary key or unique constraint is defined"
316 # Parse out a hashref from input
318 if (ref $_[0] eq 'HASH') {
319 $input_query = { %{$_[0]} };
321 elsif (@_ == @cols) {
323 @{$input_query}{@cols} = @_;
326 # Compatibility: Allow e.g. find(id => $value)
327 carp "Find by key => value deprecated; please use a hashref instead";
331 my @unique_queries = $self->_unique_queries($input_query, $attrs);
333 # Handle cases where the ResultSet defines the query, or where the user is
335 my $query = @unique_queries ? \@unique_queries : $input_query;
339 my $rs = $self->search($query, $attrs);
341 return keys %{$rs->{_attrs}->{collapse}} ? $rs->next : $rs->single;
345 return (keys %{$self->{_attrs}->{collapse}})
346 ? $self->search($query)->next
347 : $self->single($query);
353 # Build a list of queries which satisfy unique constraints.
355 sub _unique_queries {
356 my ($self, $query, $attrs) = @_;
358 my @constraint_names = exists $attrs->{key}
360 : $self->result_source->unique_constraint_names;
363 foreach my $name (@constraint_names) {
364 my @unique_cols = $self->result_source->unique_constraint_columns($name);
365 my $unique_query = $self->_build_unique_query($query, \@unique_cols);
367 next unless scalar keys %$unique_query;
369 # Add the ResultSet's alias
370 foreach my $key (grep { ! m/\./ } keys %$unique_query) {
371 my $alias = ($self->{attrs}->{_live_join}) ? $self->{attrs}->{_live_join} : $self->{attrs}->{alias};
372 $unique_query->{"$alias.$key"} = delete $unique_query->{$key};
375 push @unique_queries, $unique_query;
378 return @unique_queries;
381 # _build_unique_query
383 # Constrain the specified query hash based on the specified column names.
385 sub _build_unique_query {
386 my ($self, $query, $unique_cols) = @_;
389 map { $_ => $query->{$_} }
390 grep { exists $query->{$_} }
393 return \%unique_query;
396 =head2 search_related
400 =item Arguments: $cond, \%attrs?
402 =item Return Value: $new_resultset
406 $new_rs = $cd_rs->search_related('artist', {
410 Searches the specified relationship, optionally specifying a condition and
411 attributes for matching records. See L</ATTRIBUTES> for more information.
416 return shift->related_resultset(shift)->search(@_);
423 =item Arguments: none
425 =item Return Value: $cursor
429 Returns a storage-driven cursor to the given resultset. See
430 L<DBIx::Class::Cursor> for more information.
438 my $attrs = { %{$self->{_attrs}} };
439 return $self->{cursor}
440 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
441 $attrs->{where},$attrs);
448 =item Arguments: $cond?
450 =item Return Value: $row_object?
454 my $cd = $schema->resultset('CD')->single({ year => 2001 });
456 Inflates the first result without creating a cursor if the resultset has
457 any records in it; if not returns nothing. Used by L</find> as an optimisation.
459 Can optionally take an additional condition *only* - this is a fast-code-path
460 method; if you need to add extra joins or similar call ->search and then
461 ->single without a condition on the $rs returned from that.
466 my ($self, $where) = @_;
468 my $attrs = { %{$self->{_attrs}} };
470 if (defined $attrs->{where}) {
473 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
474 $where, delete $attrs->{where} ]
477 $attrs->{where} = $where;
481 unless ($self->_is_unique_query($attrs->{where})) {
482 carp "Query not guarnteed to return a single row"
483 . "; please declare your unique constraints or use search instead";
486 my @data = $self->result_source->storage->select_single(
487 $attrs->{from}, $attrs->{select},
488 $attrs->{where},$attrs);
489 return (@data ? $self->_construct_object(@data) : ());
494 # Try to determine if the specified query is guaranteed to be unique, based on
495 # the declared unique constraints.
497 sub _is_unique_query {
498 my ($self, $query) = @_;
500 my $collapsed = $self->_collapse_query($query);
502 my $alias = ($self->{attrs}->{_live_join}) ? $self->{attrs}->{_live_join} : $self->{attrs}->{alias};
503 foreach my $name ($self->result_source->unique_constraint_names) {
504 my @unique_cols = map { "$alias.$_" }
505 $self->result_source->unique_constraint_columns($name);
507 # Count the values for each unique column
508 my %seen = map { $_ => 0 } @unique_cols;
510 foreach my $key (keys %$collapsed) {
512 $aliased = "$alias.$key" unless $key =~ /\./;
514 next unless exists $seen{$aliased}; # Additional constraints are okay
515 $seen{$aliased} = scalar @{ $collapsed->{$key} };
518 # If we get 0 or more than 1 value for a column, it's not necessarily unique
519 return 1 unless grep { $_ != 1 } values %seen;
527 # Recursively collapse the query, accumulating values for each column.
529 sub _collapse_query {
530 my ($self, $query, $collapsed) = @_;
534 if (ref $query eq 'ARRAY') {
535 foreach my $subquery (@$query) {
536 next unless ref $subquery; # -or
537 # warn "ARRAY: " . Dumper $subquery;
538 $collapsed = $self->_collapse_query($subquery, $collapsed);
541 elsif (ref $query eq 'HASH') {
542 if (keys %$query and (keys %$query)[0] eq '-and') {
543 foreach my $subquery (@{$query->{-and}}) {
544 # warn "HASH: " . Dumper $subquery;
545 $collapsed = $self->_collapse_query($subquery, $collapsed);
549 # warn "LEAF: " . Dumper $query;
550 foreach my $key (keys %$query) {
551 push @{$collapsed->{$key}}, $query->{$key};
563 =item Arguments: $cond?
565 =item Return Value: $resultsetcolumn
569 my $max_length = $rs->get_column('length')->max;
571 Returns a ResultSetColumn instance for $column based on $self
576 my ($self, $column) = @_;
578 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
586 =item Arguments: $cond, \%attrs?
588 =item Return Value: $resultset (scalar context), @row_objs (list context)
592 # WHERE title LIKE '%blue%'
593 $cd_rs = $rs->search_like({ title => '%blue%'});
595 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
596 that this is simply a convenience method. You most likely want to use
597 L</search> with specific operators.
599 For more information, see L<DBIx::Class::Manual::Cookbook>.
605 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
606 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
607 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
608 return $class->search($query, { %$attrs });
615 =item Arguments: $first, $last
617 =item Return Value: $resultset (scalar context), @row_objs (list context)
621 Returns a resultset or object list representing a subset of elements from the
622 resultset slice is called on. Indexes are from 0, i.e., to get the first
625 my ($one, $two, $three) = $rs->slice(0, 2);
630 my ($self, $min, $max) = @_;
631 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
632 $attrs->{offset} = $self->{attrs}{offset} || 0;
633 $attrs->{offset} += $min;
634 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
635 return $self->search(undef(), $attrs);
636 #my $slice = (ref $self)->new($self->result_source, $attrs);
637 #return (wantarray ? $slice->all : $slice);
644 =item Arguments: none
646 =item Return Value: $result?
650 Returns the next element in the resultset (C<undef> is there is none).
652 Can be used to efficiently iterate over records in the resultset:
654 my $rs = $schema->resultset('CD')->search;
655 while (my $cd = $rs->next) {
659 Note that you need to store the resultset object, and call C<next> on it.
660 Calling C<< resultset('Table')->next >> repeatedly will always return the
661 first record from the resultset.
667 if (my $cache = $self->get_cache) {
668 $self->{all_cache_position} ||= 0;
669 return $cache->[$self->{all_cache_position}++];
671 if ($self->{attrs}{cache}) {
672 $self->{all_cache_position} = 1;
673 return ($self->all)[0];
675 my @row = (exists $self->{stashed_row} ?
676 @{delete $self->{stashed_row}} :
679 return unless (@row);
680 return $self->_construct_object(@row);
686 return if(exists $self->{_attrs}); #return if _resolve has already been called
688 my $attrs = $self->{attrs};
689 my $source = ($self->{_parent_rs}) ? $self->{_parent_rs} : $self->{result_source};
691 # XXX - lose storable dclone
692 my $record_filter = delete $attrs->{record_filter} if (defined $attrs->{record_filter});
693 $attrs = Storable::dclone($attrs || {}); # { %{ $attrs || {} } };
694 $attrs->{record_filter} = $record_filter if ($record_filter);
695 $self->{attrs}->{record_filter} = $record_filter if ($record_filter);
697 my $alias = $attrs->{alias};
699 $attrs->{columns} ||= delete $attrs->{cols} if $attrs->{cols};
700 delete $attrs->{as} if $attrs->{columns};
701 $attrs->{columns} ||= [ $self->{result_source}->columns ] unless $attrs->{select};
702 my $select_alias = ($self->{_parent_rs}) ? $self->{attrs}->{_live_join} : $alias;
704 map { m/\./ ? $_ : "${select_alias}.$_" } @{delete $attrs->{columns}}
705 ] if $attrs->{columns};
707 map { m/^\Q$alias.\E(.+)$/ ? $1 : $_ } @{$attrs->{select}}
709 if (my $include = delete $attrs->{include_columns}) {
710 push(@{$attrs->{select}}, @$include);
711 push(@{$attrs->{as}}, map { m/([^.]+)$/; $1; } @$include);
714 $attrs->{from} ||= [ { $alias => $source->from } ];
715 $attrs->{seen_join} ||= {};
717 if (my $join = delete $attrs->{join}) {
718 foreach my $j (ref $join eq 'ARRAY' ? @$join : ($join)) {
719 if (ref $j eq 'HASH') {
720 $seen{$_} = 1 foreach keys %$j;
726 push(@{$attrs->{from}}, $source->resolve_join($join, $attrs->{alias}, $attrs->{seen_join}));
728 $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct};
729 $attrs->{order_by} = [ $attrs->{order_by} ] if
730 $attrs->{order_by} and !ref($attrs->{order_by});
731 $attrs->{order_by} ||= [];
733 if(my $seladds = delete($attrs->{'+select'})) {
734 my @seladds = (ref($seladds) eq 'ARRAY' ? @$seladds : ($seladds));
736 @{ $attrs->{select} },
737 map { (m/\./ || ref($_)) ? $_ : "${alias}.$_" } $seladds
740 if(my $asadds = delete($attrs->{'+as'})) {
741 my @asadds = (ref($asadds) eq 'ARRAY' ? @$asadds : ($asadds));
742 $attrs->{as} = [ @{ $attrs->{as} }, @asadds ];
744 my $collapse = $attrs->{collapse} || {};
745 if (my $prefetch = delete $attrs->{prefetch}) {
747 foreach my $p (ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch)) {
748 if ( ref $p eq 'HASH' ) {
749 foreach my $key (keys %$p) {
750 push(@{$attrs->{from}}, $source->resolve_join($p, $attrs->{alias}))
754 push(@{$attrs->{from}}, $source->resolve_join($p, $attrs->{alias}))
757 #print "res pre: " . Dumper($p, $collapse);
758 my @prefetch = $source->resolve_prefetch(
759 $p, $attrs->{alias}, {}, \@pre_order, $collapse);
761 #print "prefetch: " . Dumper(\@prefetch);
762 push(@{$attrs->{select}}, map { $_->[0] } @prefetch);
763 push(@{$attrs->{as}}, map { $_->[1] } @prefetch);
765 push(@{$attrs->{order_by}}, @pre_order);
767 $attrs->{collapse} = $collapse;
768 $self->{_attrs} = $attrs;
772 my ($self, $a, $b, $is_prefetch) = @_;
775 if (ref $b eq 'HASH' && ref $a eq 'HASH') {
776 foreach my $key (keys %{$b}) {
777 if (exists $a->{$key}) {
778 $a->{$key} = $self->_merge_attr($a->{$key}, $b->{$key}, $is_prefetch);
780 $a->{$key} = $b->{$key};
785 $a = [$a] unless (ref $a eq 'ARRAY');
786 $b = [$b] unless (ref $b eq 'ARRAY');
791 foreach my $element (@{$_}) {
792 if (ref $element eq 'HASH') {
793 $hash = $self->_merge_attr($hash, $element, $is_prefetch);
794 } elsif (ref $element eq 'ARRAY') {
795 $array = [@{$array}, @{$element}];
797 if (($b == $_) && $is_prefetch) {
798 $self->_merge_array($array, $element, $is_prefetch);
800 push(@{$array}, $element);
806 my $final_array = [];
807 foreach my $element (@{$array}) {
808 push(@{$final_array}, $element) unless (exists $hash->{$element});
810 $array = $final_array;
812 if ((keys %{$hash}) && (scalar(@{$array} > 0))) {
813 return [$hash, @{$array}];
815 return (keys %{$hash}) ? $hash : $array;
821 my ($self, $a, $b) = @_;
823 $b = [$b] unless (ref $b eq 'ARRAY');
824 # add elements from @{$b} to @{$a} which aren't already in @{$a}
825 foreach my $b_element (@{$b}) {
826 push(@{$a}, $b_element) unless grep {$b_element eq $_} @{$a};
830 sub _construct_object {
831 my ($self, @row) = @_;
832 my @as = @{ $self->{_attrs}{as} };
834 #print "row in: " . Dumper(\@row);
835 my $info = $self->_collapse_result(\@as, \@row);
836 my $new = $self->result_class->inflate_result($self->result_source, @$info);
837 $new = $self->{_attrs}{record_filter}->($new)
838 if exists $self->{_attrs}{record_filter};
842 sub _collapse_result {
843 my ($self, $as, $row, $prefix) = @_;
845 my $live_join = $self->{attrs}->{_live_join} ||="";
849 foreach my $this_as (@$as) {
850 my $val = shift @copy;
851 if (defined $prefix) {
852 if ($this_as =~ m/^\Q${prefix}.\E(.+)$/) {
854 $remain =~ /^(?:(.*)\.)?([^.]+)$/;
855 $const{$1||''}{$2} = $val;
858 $this_as =~ /^(?:(.*)\.)?([^.]+)$/;
859 $const{$1||''}{$2} = $val;
863 my $info = [ {}, {} ];
864 foreach my $key (keys %const) {
865 if (length $key && $key ne $live_join) {
867 my @parts = split(/\./, $key);
868 foreach my $p (@parts) {
869 $target = $target->[1]->{$p} ||= [];
871 $target->[0] = $const{$key};
873 $info->[0] = $const{$key};
878 #print "collapse: " . Dumper($self->{_attrs}->{collapse});
879 if (defined $prefix) {
881 m/^\Q${prefix}.\E(.+)$/ ? ($1) : ()
882 } keys %{$self->{_attrs}->{collapse}}
884 @collapse = keys %{$self->{_attrs}->{collapse}};
888 my ($c) = sort { length $a <=> length $b } @collapse;
890 foreach my $p (split(/\./, $c)) {
891 $target = $target->[1]->{$p} ||= [];
893 my $c_prefix = (defined($prefix) ? "${prefix}.${c}" : $c);
894 my @co_key = @{$self->{_attrs}->{collapse}{$c_prefix}};
895 my $tree = $self->_collapse_result($as, $row, $c_prefix);
896 my %co_check = map { ($_, $tree->[0]->{$_}); } @co_key;
899 #print "les free: " . Dumper($tree->[0], \%co_check, \@co_key);
901 !defined($tree->[0]->{$_}) ||
902 $co_check{$_} ne $tree->[0]->{$_}
905 last unless (@raw = $self->cursor->next);
906 $row = $self->{stashed_row} = \@raw;
907 $tree = $self->_collapse_result($as, $row, $c_prefix);
909 @$target = (@final ? @final : [ {}, {} ]);
910 # single empty result to indicate an empty prefetched has_many
913 # get prefetch tree back to result_source level
914 # $self could be a related resultset
915 #if ($self->{attrs}->{_live_join_stack}) {
916 # foreach (@{$self->{attrs}->{_live_join_stack}}) {
917 # $info->[1] = $info->[1]->{$_}->[1] if(exists $info->[1]->{$_});
920 #print "final info: " . Dumper($info);
928 =item Arguments: $result_source?
930 =item Return Value: $result_source
934 An accessor for the primary ResultSource object from which this ResultSet
944 =item Arguments: $cond, \%attrs??
946 =item Return Value: $count
950 Performs an SQL C<COUNT> with the same query as the resultset was built
951 with to find the number of elements. If passed arguments, does a search
952 on the resultset and counts the results of that.
954 Note: When using C<count> with C<group_by>, L<DBIX::Class> emulates C<GROUP BY>
955 using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do
956 not support C<DISTINCT> with multiple columns. If you are using such a
957 database, you should only use columns from the main table in your C<group_by>
964 return $self->search(@_)->count if @_ and defined $_[0];
965 return scalar @{ $self->get_cache } if $self->get_cache;
966 my $count = $self->_count;
967 return 0 unless $count;
969 $count -= $self->{attrs}{offset} if $self->{attrs}{offset};
970 $count = $self->{attrs}{rows} if
971 $self->{attrs}{rows} and $self->{attrs}{rows} < $count;
975 sub _count { # Separated out so pager can get the full count
977 my $select = { count => '*' };
980 my $attrs = { %{ $self->{_attrs} } };
981 if (my $group_by = delete $attrs->{group_by}) {
982 delete $attrs->{having};
983 my @distinct = (ref $group_by ? @$group_by : ($group_by));
984 # todo: try CONCAT for multi-column pk
985 my @pk = $self->result_source->primary_columns;
987 foreach my $column (@distinct) {
988 if ($column =~ qr/^(?:\Q$attrs->{alias}.\E)?$pk[0]$/) {
989 @distinct = ($column);
995 $select = { count => { distinct => \@distinct } };
998 $attrs->{select} = $select;
999 $attrs->{as} = [qw/count/];
1001 # offset, order by and page are not needed to count. record_filter is cdbi
1002 delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/;
1003 my $tmp_rs = (ref $self)->new($self->result_source, $attrs);
1004 $tmp_rs->{_parent_rs} = $self->{_parent_rs} if ($self->{_parent_rs}); #XXX - hack to pass through parent of related resultsets
1006 my ($count) = $tmp_rs->cursor->next;
1010 =head2 count_literal
1014 =item Arguments: $sql_fragment, @bind_values
1016 =item Return Value: $count
1020 Counts the results in a literal query. Equivalent to calling L</search_literal>
1021 with the passed arguments, then L</count>.
1025 sub count_literal { shift->search_literal(@_)->count; }
1031 =item Arguments: none
1033 =item Return Value: @objects
1037 Returns all elements in the resultset. Called implicitly if the resultset
1038 is returned in list context.
1044 return @{ $self->get_cache } if $self->get_cache;
1048 # TODO: don't call resolve here
1050 if (keys %{$self->{_attrs}->{collapse}}) {
1051 # if ($self->{attrs}->{prefetch}) {
1052 # Using $self->cursor->all is really just an optimisation.
1053 # If we're collapsing has_many prefetches it probably makes
1054 # very little difference, and this is cleaner than hacking
1055 # _construct_object to survive the approach
1056 my @row = $self->cursor->next;
1058 push(@obj, $self->_construct_object(@row));
1059 @row = (exists $self->{stashed_row}
1060 ? @{delete $self->{stashed_row}}
1061 : $self->cursor->next);
1064 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1067 $self->set_cache(\@obj) if $self->{attrs}{cache};
1075 =item Arguments: none
1077 =item Return Value: $self
1081 Resets the resultset's cursor, so you can iterate through the elements again.
1087 delete $self->{_attrs} if (exists $self->{_attrs});
1089 $self->{all_cache_position} = 0;
1090 $self->cursor->reset;
1098 =item Arguments: none
1100 =item Return Value: $object?
1104 Resets the resultset and returns an object for the first result (if the
1105 resultset returns anything).
1110 return $_[0]->reset->next;
1113 # _cond_for_update_delete
1115 # update/delete require the condition to be modified to handle
1116 # the differing SQL syntax available. This transforms the $self->{cond}
1117 # appropriately, returning the new condition.
1119 sub _cond_for_update_delete {
1123 if (!ref($self->{cond})) {
1124 # No-op. No condition, we're updating/deleting everything
1126 elsif (ref $self->{cond} eq 'ARRAY') {
1130 foreach my $key (keys %{$_}) {
1132 $hash{$1} = $_->{$key};
1138 elsif (ref $self->{cond} eq 'HASH') {
1139 if ((keys %{$self->{cond}})[0] eq '-and') {
1142 my @cond = @{$self->{cond}{-and}};
1143 for (my $i = 0; $i <= @cond - 1; $i++) {
1144 my $entry = $cond[$i];
1147 if (ref $entry eq 'HASH') {
1148 foreach my $key (keys %{$entry}) {
1150 $hash{$1} = $entry->{$key};
1154 $entry =~ /([^.]+)$/;
1155 $hash{$1} = $cond[++$i];
1158 push @{$cond->{-and}}, \%hash;
1162 foreach my $key (keys %{$self->{cond}}) {
1164 $cond->{$1} = $self->{cond}{$key};
1169 $self->throw_exception(
1170 "Can't update/delete on resultset with condition unless hash or array"
1182 =item Arguments: \%values
1184 =item Return Value: $storage_rv
1188 Sets the specified columns in the resultset to the supplied values in a
1189 single query. Return value will be true if the update succeeded or false
1190 if no records were updated; exact type of success value is storage-dependent.
1195 my ($self, $values) = @_;
1196 $self->throw_exception("Values for update must be a hash")
1197 unless ref $values eq 'HASH';
1199 my $cond = $self->_cond_for_update_delete;
1201 return $self->result_source->storage->update(
1202 $self->result_source->from, $values, $cond
1210 =item Arguments: \%values
1212 =item Return Value: 1
1216 Fetches all objects and updates them one at a time. Note that C<update_all>
1217 will run DBIC cascade triggers, while L</update> will not.
1222 my ($self, $values) = @_;
1223 $self->throw_exception("Values for update must be a hash")
1224 unless ref $values eq 'HASH';
1225 foreach my $obj ($self->all) {
1226 $obj->set_columns($values)->update;
1235 =item Arguments: none
1237 =item Return Value: 1
1241 Deletes the contents of the resultset from its result source. Note that this
1242 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1251 my $cond = $self->_cond_for_update_delete;
1253 $self->result_source->storage->delete($self->result_source->from, $cond);
1261 =item Arguments: none
1263 =item Return Value: 1
1267 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1268 will run DBIC cascade triggers, while L</delete> will not.
1274 $_->delete for $self->all;
1282 =item Arguments: none
1284 =item Return Value: $pager
1288 Return Value a L<Data::Page> object for the current resultset. Only makes
1289 sense for queries with a C<page> attribute.
1295 my $attrs = $self->{attrs};
1296 $self->throw_exception("Can't create pager for non-paged rs")
1297 unless $self->{page};
1298 $attrs->{rows} ||= 10;
1299 return $self->{pager} ||= Data::Page->new(
1300 $self->_count, $attrs->{rows}, $self->{page});
1307 =item Arguments: $page_number
1309 =item Return Value: $rs
1313 Returns a resultset for the $page_number page of the resultset on which page
1314 is called, where each page contains a number of rows equal to the 'rows'
1315 attribute set on the resultset (10 by default).
1320 my ($self, $page) = @_;
1321 my $attrs = { %{$self->{attrs}} };
1322 $attrs->{page} = $page;
1323 return (ref $self)->new($self->result_source, $attrs);
1330 =item Arguments: \%vals
1332 =item Return Value: $object
1336 Creates an object in the resultset's result class and returns it.
1341 my ($self, $values) = @_;
1342 $self->throw_exception( "new_result needs a hash" )
1343 unless (ref $values eq 'HASH');
1344 $self->throw_exception(
1345 "Can't abstract implicit construct, condition not a hash"
1346 ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
1348 my $alias = $self->{attrs}{alias};
1349 foreach my $key (keys %{$self->{cond}||{}}) {
1350 $new{$1} = $self->{cond}{$key} if ($key =~ m/^(?:\Q${alias}.\E)?([^.]+)$/);
1352 my $obj = $self->result_class->new(\%new);
1353 $obj->result_source($self->result_source) if $obj->can('result_source');
1361 =item Arguments: \%vals, \%attrs?
1363 =item Return Value: $object
1367 Find an existing record from this resultset. If none exists, instantiate a new
1368 result object and return it. The object will not be saved into your storage
1369 until you call L<DBIx::Class::Row/insert> on it.
1371 If you want objects to be saved immediately, use L</find_or_create> instead.
1377 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1378 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1379 my $exists = $self->find($hash, $attrs);
1380 return defined $exists ? $exists : $self->new_result($hash);
1387 =item Arguments: \%vals
1389 =item Return Value: $object
1393 Inserts a record into the resultset and returns the object representing it.
1395 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
1400 my ($self, $attrs) = @_;
1401 $self->throw_exception( "create needs a hashref" )
1402 unless ref $attrs eq 'HASH';
1403 return $self->new_result($attrs)->insert;
1406 =head2 find_or_create
1410 =item Arguments: \%vals, \%attrs?
1412 =item Return Value: $object
1416 $class->find_or_create({ key => $val, ... });
1418 Tries to find a record based on its primary key or unique constraint; if none
1419 is found, creates one and returns that instead.
1421 my $cd = $schema->resultset('CD')->find_or_create({
1423 artist => 'Massive Attack',
1424 title => 'Mezzanine',
1428 Also takes an optional C<key> attribute, to search by a specific key or unique
1429 constraint. For example:
1431 my $cd = $schema->resultset('CD')->find_or_create(
1433 artist => 'Massive Attack',
1434 title => 'Mezzanine',
1436 { key => 'cd_artist_title' }
1439 See also L</find> and L</update_or_create>. For information on how to declare
1440 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1444 sub find_or_create {
1446 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1447 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1448 my $exists = $self->find($hash, $attrs);
1449 return defined $exists ? $exists : $self->create($hash);
1452 =head2 update_or_create
1456 =item Arguments: \%col_values, { key => $unique_constraint }?
1458 =item Return Value: $object
1462 $class->update_or_create({ col => $val, ... });
1464 First, searches for an existing row matching one of the unique constraints
1465 (including the primary key) on the source of this resultset. If a row is
1466 found, updates it with the other given column values. Otherwise, creates a new
1469 Takes an optional C<key> attribute to search on a specific unique constraint.
1472 # In your application
1473 my $cd = $schema->resultset('CD')->update_or_create(
1475 artist => 'Massive Attack',
1476 title => 'Mezzanine',
1479 { key => 'cd_artist_title' }
1482 If no C<key> is specified, it searches on all unique constraints defined on the
1483 source, including the primary key.
1485 If the C<key> is specified as C<primary>, it searches only on the primary key.
1487 See also L</find> and L</find_or_create>. For information on how to declare
1488 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1492 sub update_or_create {
1494 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1495 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
1497 my $row = $self->find($cond);
1499 $row->update($cond);
1503 return $self->create($cond);
1510 =item Arguments: none
1512 =item Return Value: \@cache_objects?
1516 Gets the contents of the cache for the resultset, if the cache is set.
1528 =item Arguments: \@cache_objects
1530 =item Return Value: \@cache_objects
1534 Sets the contents of the cache for the resultset. Expects an arrayref
1535 of objects of the same class as those produced by the resultset. Note that
1536 if the cache is set the resultset will return the cached objects rather
1537 than re-querying the database even if the cache attr is not set.
1542 my ( $self, $data ) = @_;
1543 $self->throw_exception("set_cache requires an arrayref")
1544 if defined($data) && (ref $data ne 'ARRAY');
1545 $self->{all_cache} = $data;
1552 =item Arguments: none
1554 =item Return Value: []
1558 Clears the cache for the resultset.
1563 shift->set_cache(undef);
1566 =head2 related_resultset
1570 =item Arguments: $relationship_name
1572 =item Return Value: $resultset
1576 Returns a related resultset for the supplied relationship name.
1578 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
1582 sub related_resultset {
1583 my ( $self, $rel ) = @_;
1585 $self->{related_resultsets} ||= {};
1586 return $self->{related_resultsets}{$rel} ||= do {
1587 #warn "fetching related resultset for rel '$rel' " . $self->result_source->{name};
1588 my $rel_obj = $self->result_source->relationship_info($rel);
1589 $self->throw_exception(
1590 "search_related: result source '" . $self->result_source->name .
1591 "' has no such relationship ${rel}")
1592 unless $rel_obj; #die Dumper $self->{attrs};
1594 my $live_join_stack = $self->{attrs}->{_live_join_stack} || [];
1595 push(@{$live_join_stack}, $rel);
1597 my $rs = $self->result_source->schema->resultset($rel_obj->{class}
1601 _live_join => $rel, #the most recent
1602 _live_join_stack => $live_join_stack, #the trail of rels
1603 _parent_attrs => $self->{attrs}}
1606 # keep reference of the original resultset
1607 $rs->{_parent_rs} = ($self->{_parent_rs}) ? $self->{_parent_rs} : $self->result_source;
1612 =head2 throw_exception
1614 See L<DBIx::Class::Schema/throw_exception> for details.
1618 sub throw_exception {
1620 $self->result_source->schema->throw_exception(@_);
1623 # XXX: FIXME: Attributes docs need clearing up
1627 The resultset takes various attributes that modify its behavior. Here's an
1634 =item Value: ($order_by | \@order_by)
1638 Which column(s) to order the results by. This is currently passed
1639 through directly to SQL, so you can give e.g. C<year DESC> for a
1640 descending order on the column `year'.
1642 Please note that if you have quoting enabled (see
1643 L<DBIx::Class::Storage/quote_char>) you will need to do C<\'year DESC' > to
1644 specify an order. (The scalar ref causes it to be passed as raw sql to the DB,
1645 so you will need to manually quote things as appropriate.)
1651 =item Value: \@columns
1655 Shortcut to request a particular set of columns to be retrieved. Adds
1656 C<me.> onto the start of any column without a C<.> in it and sets C<select>
1657 from that, then auto-populates C<as> from C<select> as normal. (You may also
1658 use the C<cols> attribute, as in earlier versions of DBIC.)
1660 =head2 include_columns
1664 =item Value: \@columns
1668 Shortcut to include additional columns in the returned results - for example
1670 $schema->resultset('CD')->search(undef, {
1671 include_columns => ['artist.name'],
1675 would return all CDs and include a 'name' column to the information
1676 passed to object inflation
1682 =item Value: \@select_columns
1686 Indicates which columns should be selected from the storage. You can use
1687 column names, or in the case of RDBMS back ends, function or stored procedure
1690 $rs = $schema->resultset('Employee')->search(undef, {
1693 { count => 'employeeid' },
1698 When you use function/stored procedure names and do not supply an C<as>
1699 attribute, the column names returned are storage-dependent. E.g. MySQL would
1700 return a column named C<count(employeeid)> in the above example.
1706 Indicates additional columns to be selected from storage. Works the same as
1707 L<select> but adds columns to the selection.
1715 Indicates additional column names for those added via L<+select>.
1723 =item Value: \@inflation_names
1727 Indicates column names for object inflation. This is used in conjunction with
1728 C<select>, usually when C<select> contains one or more function or stored
1731 $rs = $schema->resultset('Employee')->search(undef, {
1734 { count => 'employeeid' }
1736 as => ['name', 'employee_count'],
1739 my $employee = $rs->first(); # get the first Employee
1741 If the object against which the search is performed already has an accessor
1742 matching a column name specified in C<as>, the value can be retrieved using
1743 the accessor as normal:
1745 my $name = $employee->name();
1747 If on the other hand an accessor does not exist in the object, you need to
1748 use C<get_column> instead:
1750 my $employee_count = $employee->get_column('employee_count');
1752 You can create your own accessors if required - see
1753 L<DBIx::Class::Manual::Cookbook> for details.
1755 Please note: This will NOT insert an C<AS employee_count> into the SQL statement
1756 produced, it is used for internal access only. Thus attempting to use the accessor
1757 in an C<order_by> clause or similar will fail misrably.
1763 =item Value: ($rel_name | \@rel_names | \%rel_names)
1767 Contains a list of relationships that should be joined for this query. For
1770 # Get CDs by Nine Inch Nails
1771 my $rs = $schema->resultset('CD')->search(
1772 { 'artist.name' => 'Nine Inch Nails' },
1773 { join => 'artist' }
1776 Can also contain a hash reference to refer to the other relation's relations.
1779 package MyApp::Schema::Track;
1780 use base qw/DBIx::Class/;
1781 __PACKAGE__->table('track');
1782 __PACKAGE__->add_columns(qw/trackid cd position title/);
1783 __PACKAGE__->set_primary_key('trackid');
1784 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
1787 # In your application
1788 my $rs = $schema->resultset('Artist')->search(
1789 { 'track.title' => 'Teardrop' },
1791 join => { cd => 'track' },
1792 order_by => 'artist.name',
1796 If the same join is supplied twice, it will be aliased to <rel>_2 (and
1797 similarly for a third time). For e.g.
1799 my $rs = $schema->resultset('Artist')->search({
1800 'cds.title' => 'Down to Earth',
1801 'cds_2.title' => 'Popular',
1803 join => [ qw/cds cds/ ],
1806 will return a set of all artists that have both a cd with title 'Down
1807 to Earth' and a cd with title 'Popular'.
1809 If you want to fetch related objects from other tables as well, see C<prefetch>
1816 =item Value: ($rel_name | \@rel_names | \%rel_names)
1820 Contains one or more relationships that should be fetched along with the main
1821 query (when they are accessed afterwards they will have already been
1822 "prefetched"). This is useful for when you know you will need the related
1823 objects, because it saves at least one query:
1825 my $rs = $schema->resultset('Tag')->search(
1834 The initial search results in SQL like the following:
1836 SELECT tag.*, cd.*, artist.* FROM tag
1837 JOIN cd ON tag.cd = cd.cdid
1838 JOIN artist ON cd.artist = artist.artistid
1840 L<DBIx::Class> has no need to go back to the database when we access the
1841 C<cd> or C<artist> relationships, which saves us two SQL statements in this
1844 Simple prefetches will be joined automatically, so there is no need
1845 for a C<join> attribute in the above search. If you're prefetching to
1846 depth (e.g. { cd => { artist => 'label' } or similar), you'll need to
1847 specify the join as well.
1849 C<prefetch> can be used with the following relationship types: C<belongs_to>,
1850 C<has_one> (or if you're using C<add_relationship>, any relationship declared
1851 with an accessor type of 'single' or 'filter').
1861 Makes the resultset paged and specifies the page to retrieve. Effectively
1862 identical to creating a non-pages resultset and then calling ->page($page)
1865 If L<rows> attribute is not specified it defualts to 10 rows per page.
1875 Specifes the maximum number of rows for direct retrieval or the number of
1876 rows per page if the page attribute or method is used.
1882 =item Value: $offset
1886 Specifies the (zero-based) row number for the first row to be returned, or the
1887 of the first row of the first page if paging is used.
1893 =item Value: \@columns
1897 A arrayref of columns to group by. Can include columns of joined tables.
1899 group_by => [qw/ column1 column2 ... /]
1905 =item Value: $condition
1909 HAVING is a select statement attribute that is applied between GROUP BY and
1910 ORDER BY. It is applied to the after the grouping calculations have been
1913 having => { 'count(employee)' => { '>=', 100 } }
1919 =item Value: (0 | 1)
1923 Set to 1 to group by all columns.
1927 Set to 1 to cache search results. This prevents extra SQL queries if you
1928 revisit rows in your ResultSet:
1930 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
1932 while( my $artist = $resultset->next ) {
1936 $rs->first; # without cache, this would issue a query
1938 By default, searches are not cached.
1940 For more examples of using these attributes, see
1941 L<DBIx::Class::Manual::Cookbook>.
1947 =item Value: \@from_clause
1951 The C<from> attribute gives you manual control over the C<FROM> clause of SQL
1952 statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
1955 NOTE: Use this on your own risk. This allows you to shoot off your foot!
1957 C<join> will usually do what you need and it is strongly recommended that you
1958 avoid using C<from> unless you cannot achieve the desired result using C<join>.
1959 And we really do mean "cannot", not just tried and failed. Attempting to use
1960 this because you're having problems with C<join> is like trying to use x86
1961 ASM because you've got a syntax error in your C. Trust us on this.
1963 Now, if you're still really, really sure you need to use this (and if you're
1964 not 100% sure, ask the mailing list first), here's an explanation of how this
1967 The syntax is as follows -
1970 { <alias1> => <table1> },
1972 { <alias2> => <table2>, -join_type => 'inner|left|right' },
1973 [], # nested JOIN (optional)
1974 { <table1.column1> => <table2.column2>, ... (more conditions) },
1976 # More of the above [ ] may follow for additional joins
1983 ON <table1.column1> = <table2.column2>
1984 <more joins may follow>
1986 An easy way to follow the examples below is to remember the following:
1988 Anything inside "[]" is a JOIN
1989 Anything inside "{}" is a condition for the enclosing JOIN
1991 The following examples utilize a "person" table in a family tree application.
1992 In order to express parent->child relationships, this table is self-joined:
1994 # Person->belongs_to('father' => 'Person');
1995 # Person->belongs_to('mother' => 'Person');
1997 C<from> can be used to nest joins. Here we return all children with a father,
1998 then search against all mothers of those children:
2000 $rs = $schema->resultset('Person')->search(
2003 alias => 'mother', # alias columns in accordance with "from"
2005 { mother => 'person' },
2008 { child => 'person' },
2010 { father => 'person' },
2011 { 'father.person_id' => 'child.father_id' }
2014 { 'mother.person_id' => 'child.mother_id' }
2021 # SELECT mother.* FROM person mother
2024 # JOIN person father
2025 # ON ( father.person_id = child.father_id )
2027 # ON ( mother.person_id = child.mother_id )
2029 The type of any join can be controlled manually. To search against only people
2030 with a father in the person table, we could explicitly use C<INNER JOIN>:
2032 $rs = $schema->resultset('Person')->search(
2035 alias => 'child', # alias columns in accordance with "from"
2037 { child => 'person' },
2039 { father => 'person', -join_type => 'inner' },
2040 { 'father.id' => 'child.father_id' }
2047 # SELECT child.* FROM person child
2048 # INNER JOIN person father ON child.father_id = father.id