1 package DBIx::Class::ResultSet;
9 use Carp::Clan qw/^DBIx::Class/;
12 use DBIx::Class::ResultSetColumn;
13 use DBIx::Class::ResultSourceHandle;
14 use base qw/DBIx::Class/;
16 __PACKAGE__->mk_group_accessors('simple' => qw/result_class _source_handle/);
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) = @_;
88 $source = $source->handle
89 unless $source->isa('DBIx::Class::ResultSourceHandle');
90 $attrs = { %{$attrs||{}} };
93 $attrs->{rows} ||= 10;
96 $attrs->{alias} ||= 'me';
99 _source_handle => $source,
100 result_class => $attrs->{result_class} || $source->resolve->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
137 L</ATTRIBUTES>. For more examples of using this function, see
138 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
139 documentation for the first argument, see L<SQL::Abstract>.
145 my $rs = $self->search_rs( @_ );
146 return (wantarray ? $rs->all : $rs);
153 =item Arguments: $cond, \%attrs?
155 =item Return Value: $resultset
159 This method does the same exact thing as search() except it will
160 always return a resultset, even in list context.
169 unless (@_) { # no search, effectively just a clone
170 $rows = $self->get_cache;
174 $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
175 my $our_attrs = { %{$self->{attrs}} };
176 my $having = delete $our_attrs->{having};
177 my $where = delete $our_attrs->{where};
179 my $new_attrs = { %{$our_attrs}, %{$attrs} };
181 # merge new attrs into inherited
182 foreach my $key (qw/join prefetch/) {
183 next unless exists $attrs->{$key};
184 $new_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key});
189 (@_ == 1 || ref $_[0] eq "HASH")
191 (ref $_[0] eq 'HASH')
193 (keys %{ $_[0] } > 0)
201 ? $self->throw_exception("Odd number of arguments to search")
208 if (defined $where) {
209 $new_attrs->{where} = (
210 defined $new_attrs->{where}
213 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
214 } $where, $new_attrs->{where}
221 $new_attrs->{where} = (
222 defined $new_attrs->{where}
225 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
226 } $cond, $new_attrs->{where}
232 if (defined $having) {
233 $new_attrs->{having} = (
234 defined $new_attrs->{having}
237 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
238 } $having, $new_attrs->{having}
244 my $rs = (ref $self)->new($self->result_source, $new_attrs);
246 $rs->set_cache($rows);
251 =head2 search_literal
255 =item Arguments: $sql_fragment, @bind_values
257 =item Return Value: $resultset (scalar context), @row_objs (list context)
261 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
262 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
264 Pass a literal chunk of SQL to be added to the conditional part of the
270 my ($self, $cond, @vals) = @_;
271 my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {});
272 $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ];
273 return $self->search(\$cond, $attrs);
280 =item Arguments: @values | \%cols, \%attrs?
282 =item Return Value: $row_object
286 Finds a row based on its primary key or unique constraint. For example, to find
287 a row by its primary key:
289 my $cd = $schema->resultset('CD')->find(5);
291 You can also find a row by a specific unique constraint using the C<key>
292 attribute. For example:
294 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
295 key => 'cd_artist_title'
298 Additionally, you can specify the columns explicitly by name:
300 my $cd = $schema->resultset('CD')->find(
302 artist => 'Massive Attack',
303 title => 'Mezzanine',
305 { key => 'cd_artist_title' }
308 If the C<key> is specified as C<primary>, it searches only on the primary key.
310 If no C<key> is specified, it searches on all unique constraints defined on the
311 source, including the primary key.
313 If your table does not have a primary key, you B<must> provide a value for the
314 C<key> attribute matching one of the unique constraints on the source.
316 See also L</find_or_create> and L</update_or_create>. For information on how to
317 declare unique constraints, see
318 L<DBIx::Class::ResultSource/add_unique_constraint>.
324 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
326 # Default to the primary key, but allow a specific key
327 my @cols = exists $attrs->{key}
328 ? $self->result_source->unique_constraint_columns($attrs->{key})
329 : $self->result_source->primary_columns;
330 $self->throw_exception(
331 "Can't find unless a primary key is defined or unique constraint is specified"
334 # Parse out a hashref from input
336 if (ref $_[0] eq 'HASH') {
337 $input_query = { %{$_[0]} };
339 elsif (@_ == @cols) {
341 @{$input_query}{@cols} = @_;
344 # Compatibility: Allow e.g. find(id => $value)
345 carp "Find by key => value deprecated; please use a hashref instead";
349 my (%related, $info);
351 KEY: foreach my $key (keys %$input_query) {
352 if (ref($input_query->{$key})
353 && ($info = $self->result_source->relationship_info($key))) {
354 my $val = delete $input_query->{$key};
355 next KEY if (ref($val) eq 'ARRAY'); # has_many for multi_create
356 my $rel_q = $self->result_source->resolve_condition(
357 $info->{cond}, $val, $key
359 die "Can't handle OR join condition in find" if ref($rel_q) eq 'ARRAY';
360 @related{keys %$rel_q} = values %$rel_q;
363 if (my @keys = keys %related) {
364 @{$input_query}{@keys} = values %related;
367 my @unique_queries = $self->_unique_queries($input_query, $attrs);
369 # Build the final query: Default to the disjunction of the unique queries,
370 # but allow the input query in case the ResultSet defines the query or the
371 # user is abusing find
372 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
373 my $query = @unique_queries
374 ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
375 : $self->_add_alias($input_query, $alias);
379 my $rs = $self->search($query, $attrs);
380 return keys %{$rs->_resolved_attrs->{collapse}} ? $rs->next : $rs->single;
383 return keys %{$self->_resolved_attrs->{collapse}}
384 ? $self->search($query)->next
385 : $self->single($query);
391 # Add the specified alias to the specified query hash. A copy is made so the
392 # original query is not modified.
395 my ($self, $query, $alias) = @_;
397 my %aliased = %$query;
398 foreach my $col (grep { ! m/\./ } keys %aliased) {
399 $aliased{"$alias.$col"} = delete $aliased{$col};
407 # Build a list of queries which satisfy unique constraints.
409 sub _unique_queries {
410 my ($self, $query, $attrs) = @_;
412 my @constraint_names = exists $attrs->{key}
414 : $self->result_source->unique_constraint_names;
416 my $where = $self->_collapse_cond($self->{attrs}{where} || {});
417 my $num_where = scalar keys %$where;
420 foreach my $name (@constraint_names) {
421 my @unique_cols = $self->result_source->unique_constraint_columns($name);
422 my $unique_query = $self->_build_unique_query($query, \@unique_cols);
424 my $num_cols = scalar @unique_cols;
425 my $num_query = scalar keys %$unique_query;
427 my $total = $num_query + $num_where;
428 if ($num_query && ($num_query == $num_cols || $total == $num_cols)) {
429 # The query is either unique on its own or is unique in combination with
430 # the existing where clause
431 push @unique_queries, $unique_query;
435 return @unique_queries;
438 # _build_unique_query
440 # Constrain the specified query hash based on the specified column names.
442 sub _build_unique_query {
443 my ($self, $query, $unique_cols) = @_;
446 map { $_ => $query->{$_} }
447 grep { exists $query->{$_} }
452 =head2 search_related
456 =item Arguments: $rel, $cond, \%attrs?
458 =item Return Value: $new_resultset
462 $new_rs = $cd_rs->search_related('artist', {
466 Searches the specified relationship, optionally specifying a condition and
467 attributes for matching records. See L</ATTRIBUTES> for more information.
472 return shift->related_resultset(shift)->search(@_);
479 =item Arguments: none
481 =item Return Value: $cursor
485 Returns a storage-driven cursor to the given resultset. See
486 L<DBIx::Class::Cursor> for more information.
493 my $attrs = { %{$self->_resolved_attrs} };
494 return $self->{cursor}
495 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
496 $attrs->{where},$attrs);
503 =item Arguments: $cond?
505 =item Return Value: $row_object?
509 my $cd = $schema->resultset('CD')->single({ year => 2001 });
511 Inflates the first result without creating a cursor if the resultset has
512 any records in it; if not returns nothing. Used by L</find> as an optimisation.
514 Can optionally take an additional condition *only* - this is a fast-code-path
515 method; if you need to add extra joins or similar call ->search and then
516 ->single without a condition on the $rs returned from that.
521 my ($self, $where) = @_;
522 my $attrs = { %{$self->_resolved_attrs} };
524 if (defined $attrs->{where}) {
527 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
528 $where, delete $attrs->{where} ]
531 $attrs->{where} = $where;
535 # XXX: Disabled since it doesn't infer uniqueness in all cases
536 # unless ($self->_is_unique_query($attrs->{where})) {
537 # carp "Query not guaranteed to return a single row"
538 # . "; please declare your unique constraints or use search instead";
541 my @data = $self->result_source->storage->select_single(
542 $attrs->{from}, $attrs->{select},
543 $attrs->{where}, $attrs
546 return (@data ? ($self->_construct_object(@data))[0] : undef);
551 # Try to determine if the specified query is guaranteed to be unique, based on
552 # the declared unique constraints.
554 sub _is_unique_query {
555 my ($self, $query) = @_;
557 my $collapsed = $self->_collapse_query($query);
558 my $alias = $self->{attrs}{alias};
560 foreach my $name ($self->result_source->unique_constraint_names) {
561 my @unique_cols = map {
563 } $self->result_source->unique_constraint_columns($name);
565 # Count the values for each unique column
566 my %seen = map { $_ => 0 } @unique_cols;
568 foreach my $key (keys %$collapsed) {
569 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
570 next unless exists $seen{$aliased}; # Additional constraints are okay
571 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
574 # If we get 0 or more than 1 value for a column, it's not necessarily unique
575 return 1 unless grep { $_ != 1 } values %seen;
583 # Recursively collapse the query, accumulating values for each column.
585 sub _collapse_query {
586 my ($self, $query, $collapsed) = @_;
590 if (ref $query eq 'ARRAY') {
591 foreach my $subquery (@$query) {
592 next unless ref $subquery; # -or
593 # warn "ARRAY: " . Dumper $subquery;
594 $collapsed = $self->_collapse_query($subquery, $collapsed);
597 elsif (ref $query eq 'HASH') {
598 if (keys %$query and (keys %$query)[0] eq '-and') {
599 foreach my $subquery (@{$query->{-and}}) {
600 # warn "HASH: " . Dumper $subquery;
601 $collapsed = $self->_collapse_query($subquery, $collapsed);
605 # warn "LEAF: " . Dumper $query;
606 foreach my $col (keys %$query) {
607 my $value = $query->{$col};
608 $collapsed->{$col}{$value}++;
620 =item Arguments: $cond?
622 =item Return Value: $resultsetcolumn
626 my $max_length = $rs->get_column('length')->max;
628 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
633 my ($self, $column) = @_;
634 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
642 =item Arguments: $cond, \%attrs?
644 =item Return Value: $resultset (scalar context), @row_objs (list context)
648 # WHERE title LIKE '%blue%'
649 $cd_rs = $rs->search_like({ title => '%blue%'});
651 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
652 that this is simply a convenience method. You most likely want to use
653 L</search> with specific operators.
655 For more information, see L<DBIx::Class::Manual::Cookbook>.
661 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
662 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
663 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
664 return $class->search($query, { %$attrs });
671 =item Arguments: $first, $last
673 =item Return Value: $resultset (scalar context), @row_objs (list context)
677 Returns a resultset or object list representing a subset of elements from the
678 resultset slice is called on. Indexes are from 0, i.e., to get the first
681 my ($one, $two, $three) = $rs->slice(0, 2);
686 my ($self, $min, $max) = @_;
687 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
688 $attrs->{offset} = $self->{attrs}{offset} || 0;
689 $attrs->{offset} += $min;
690 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
691 return $self->search(undef(), $attrs);
692 #my $slice = (ref $self)->new($self->result_source, $attrs);
693 #return (wantarray ? $slice->all : $slice);
700 =item Arguments: none
702 =item Return Value: $result?
706 Returns the next element in the resultset (C<undef> is there is none).
708 Can be used to efficiently iterate over records in the resultset:
710 my $rs = $schema->resultset('CD')->search;
711 while (my $cd = $rs->next) {
715 Note that you need to store the resultset object, and call C<next> on it.
716 Calling C<< resultset('Table')->next >> repeatedly will always return the
717 first record from the resultset.
723 if (my $cache = $self->get_cache) {
724 $self->{all_cache_position} ||= 0;
725 return $cache->[$self->{all_cache_position}++];
727 if ($self->{attrs}{cache}) {
728 $self->{all_cache_position} = 1;
729 return ($self->all)[0];
731 if ($self->{stashed_objects}) {
732 my $obj = shift(@{$self->{stashed_objects}});
733 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
737 exists $self->{stashed_row}
738 ? @{delete $self->{stashed_row}}
739 : $self->cursor->next
741 return undef unless (@row);
742 my ($row, @more) = $self->_construct_object(@row);
743 $self->{stashed_objects} = \@more if @more;
747 sub _construct_object {
748 my ($self, @row) = @_;
749 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row);
750 my @new = $self->result_class->inflate_result($self->result_source, @$info);
751 @new = $self->{_attrs}{record_filter}->(@new)
752 if exists $self->{_attrs}{record_filter};
756 sub _collapse_result {
757 my ($self, $as_proto, $row) = @_;
761 # 'foo' => [ undef, 'foo' ]
762 # 'foo.bar' => [ 'foo', 'bar' ]
763 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
765 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
767 my %collapse = %{$self->{_attrs}{collapse}||{}};
771 # if we're doing collapsing (has_many prefetch) we need to grab records
772 # until the PK changes, so fill @pri_index. if not, we leave it empty so
773 # we know we don't have to bother.
775 # the reason for not using the collapse stuff directly is because if you
776 # had for e.g. two artists in a row with no cds, the collapse info for
777 # both would be NULL (undef) so you'd lose the second artist
779 # store just the index so we can check the array positions from the row
780 # without having to contruct the full hash
782 if (keys %collapse) {
783 my %pri = map { ($_ => 1) } $self->result_source->primary_columns;
784 foreach my $i (0 .. $#construct_as) {
785 next if defined($construct_as[$i][0]); # only self table
786 if (delete $pri{$construct_as[$i][1]}) {
787 push(@pri_index, $i);
789 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
793 # no need to do an if, it'll be empty if @pri_index is empty anyway
795 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
799 do { # no need to check anything at the front, we always want the first row
803 foreach my $this_as (@construct_as) {
804 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
807 push(@const_rows, \%const);
809 } until ( # no pri_index => no collapse => drop straight out
812 do { # get another row, stash it, drop out if different PK
814 @copy = $self->cursor->next;
815 $self->{stashed_row} = \@copy;
817 # last thing in do block, counts as true if anything doesn't match
819 # check xor defined first for NULL vs. NOT NULL then if one is
820 # defined the other must be so check string equality
823 (defined $pri_vals{$_} ^ defined $copy[$_])
824 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
829 my $alias = $self->{attrs}{alias};
836 foreach my $const (@const_rows) {
837 scalar @const_keys or do {
838 @const_keys = sort { length($a) <=> length($b) } keys %$const;
840 foreach my $key (@const_keys) {
843 my @parts = split(/\./, $key);
845 my $data = $const->{$key};
846 foreach my $p (@parts) {
847 $target = $target->[1]->{$p} ||= [];
849 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
850 # collapsing at this point and on final part
851 my $pos = $collapse_pos{$cur};
852 CK: foreach my $ck (@ckey) {
853 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
854 $collapse_pos{$cur} = $data;
855 delete @collapse_pos{ # clear all positioning for sub-entries
856 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
863 if (exists $collapse{$cur}) {
864 $target = $target->[-1];
867 $target->[0] = $data;
869 $info->[0] = $const->{$key};
881 =item Arguments: $result_source?
883 =item Return Value: $result_source
887 An accessor for the primary ResultSource object from which this ResultSet
894 =item Arguments: $result_class?
896 =item Return Value: $result_class
900 An accessor for the class to use when creating row objects. Defaults to
901 C<< result_source->result_class >> - which in most cases is the name of the
902 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
911 =item Arguments: $cond, \%attrs??
913 =item Return Value: $count
917 Performs an SQL C<COUNT> with the same query as the resultset was built
918 with to find the number of elements. If passed arguments, does a search
919 on the resultset and counts the results of that.
921 Note: When using C<count> with C<group_by>, L<DBIX::Class> emulates C<GROUP BY>
922 using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do
923 not support C<DISTINCT> with multiple columns. If you are using such a
924 database, you should only use columns from the main table in your C<group_by>
931 return $self->search(@_)->count if @_ and defined $_[0];
932 return scalar @{ $self->get_cache } if $self->get_cache;
933 my $count = $self->_count;
934 return 0 unless $count;
936 # need to take offset from resolved attrs
938 $count -= $self->{_attrs}{offset} if $self->{_attrs}{offset};
939 $count = $self->{attrs}{rows} if
940 $self->{attrs}{rows} and $self->{attrs}{rows} < $count;
941 $count = 0 if ($count < 0);
945 sub _count { # Separated out so pager can get the full count
947 my $select = { count => '*' };
949 my $attrs = { %{$self->_resolved_attrs} };
950 if (my $group_by = delete $attrs->{group_by}) {
951 delete $attrs->{having};
952 my @distinct = (ref $group_by ? @$group_by : ($group_by));
953 # todo: try CONCAT for multi-column pk
954 my @pk = $self->result_source->primary_columns;
956 my $alias = $attrs->{alias};
957 foreach my $column (@distinct) {
958 if ($column =~ qr/^(?:\Q${alias}.\E)?$pk[0]$/) {
959 @distinct = ($column);
965 $select = { count => { distinct => \@distinct } };
968 $attrs->{select} = $select;
969 $attrs->{as} = [qw/count/];
971 # offset, order by and page are not needed to count. record_filter is cdbi
972 delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/;
974 my $tmp_rs = (ref $self)->new($self->_source_handle, $attrs);
975 my ($count) = $tmp_rs->cursor->next;
983 =item Arguments: $sql_fragment, @bind_values
985 =item Return Value: $count
989 Counts the results in a literal query. Equivalent to calling L</search_literal>
990 with the passed arguments, then L</count>.
994 sub count_literal { shift->search_literal(@_)->count; }
1000 =item Arguments: none
1002 =item Return Value: @objects
1006 Returns all elements in the resultset. Called implicitly if the resultset
1007 is returned in list context.
1013 return @{ $self->get_cache } if $self->get_cache;
1017 # TODO: don't call resolve here
1018 if (keys %{$self->_resolved_attrs->{collapse}}) {
1019 # if ($self->{attrs}{prefetch}) {
1020 # Using $self->cursor->all is really just an optimisation.
1021 # If we're collapsing has_many prefetches it probably makes
1022 # very little difference, and this is cleaner than hacking
1023 # _construct_object to survive the approach
1024 my @row = $self->cursor->next;
1026 push(@obj, $self->_construct_object(@row));
1027 @row = (exists $self->{stashed_row}
1028 ? @{delete $self->{stashed_row}}
1029 : $self->cursor->next);
1032 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1035 $self->set_cache(\@obj) if $self->{attrs}{cache};
1043 =item Arguments: none
1045 =item Return Value: $self
1049 Resets the resultset's cursor, so you can iterate through the elements again.
1055 delete $self->{_attrs} if exists $self->{_attrs};
1056 $self->{all_cache_position} = 0;
1057 $self->cursor->reset;
1065 =item Arguments: none
1067 =item Return Value: $object?
1071 Resets the resultset and returns an object for the first result (if the
1072 resultset returns anything).
1077 return $_[0]->reset->next;
1080 # _cond_for_update_delete
1082 # update/delete require the condition to be modified to handle
1083 # the differing SQL syntax available. This transforms the $self->{cond}
1084 # appropriately, returning the new condition.
1086 sub _cond_for_update_delete {
1087 my ($self, $full_cond) = @_;
1090 $full_cond ||= $self->{cond};
1091 # No-op. No condition, we're updating/deleting everything
1092 return $cond unless ref $full_cond;
1094 if (ref $full_cond eq 'ARRAY') {
1098 foreach my $key (keys %{$_}) {
1100 $hash{$1} = $_->{$key};
1106 elsif (ref $full_cond eq 'HASH') {
1107 if ((keys %{$full_cond})[0] eq '-and') {
1110 my @cond = @{$full_cond->{-and}};
1111 for (my $i = 0; $i < @cond; $i++) {
1112 my $entry = $cond[$i];
1115 if (ref $entry eq 'HASH') {
1116 $hash = $self->_cond_for_update_delete($entry);
1119 $entry =~ /([^.]+)$/;
1120 $hash->{$1} = $cond[++$i];
1123 push @{$cond->{-and}}, $hash;
1127 foreach my $key (keys %{$full_cond}) {
1129 $cond->{$1} = $full_cond->{$key};
1134 $self->throw_exception(
1135 "Can't update/delete on resultset with condition unless hash or array"
1147 =item Arguments: \%values
1149 =item Return Value: $storage_rv
1153 Sets the specified columns in the resultset to the supplied values in a
1154 single query. Return value will be true if the update succeeded or false
1155 if no records were updated; exact type of success value is storage-dependent.
1160 my ($self, $values) = @_;
1161 $self->throw_exception("Values for update must be a hash")
1162 unless ref $values eq 'HASH';
1164 my $cond = $self->_cond_for_update_delete;
1166 return $self->result_source->storage->update(
1167 $self->result_source, $values, $cond
1175 =item Arguments: \%values
1177 =item Return Value: 1
1181 Fetches all objects and updates them one at a time. Note that C<update_all>
1182 will run DBIC cascade triggers, while L</update> will not.
1187 my ($self, $values) = @_;
1188 $self->throw_exception("Values for update must be a hash")
1189 unless ref $values eq 'HASH';
1190 foreach my $obj ($self->all) {
1191 $obj->set_columns($values)->update;
1200 =item Arguments: none
1202 =item Return Value: 1
1206 Deletes the contents of the resultset from its result source. Note that this
1207 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1208 to run. See also L<DBIx::Class::Row/delete>.
1215 my $cond = $self->_cond_for_update_delete;
1217 $self->result_source->storage->delete($self->result_source, $cond);
1225 =item Arguments: none
1227 =item Return Value: 1
1231 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1232 will run DBIC cascade triggers, while L</delete> will not.
1238 $_->delete for $self->all;
1246 =item Arguments: \@data;
1250 Pass an arrayref of hashrefs. Each hashref should be a structure suitable for
1251 submitting to a $resultset->create(...) method.
1253 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1254 to insert the data, as this is a faster method.
1256 Otherwise, each set of data is inserted into the database using
1257 L<DBIx::Class::ResultSet/create>, and a arrayref of the resulting row
1258 objects is returned.
1260 Example: Assuming an Artist Class that has many CDs Classes relating:
1262 my $Artist_rs = $schema->resultset("Artist");
1264 ## Void Context Example
1265 $Artist_rs->populate([
1266 { artistid => 4, name => 'Manufactured Crap', cds => [
1267 { title => 'My First CD', year => 2006 },
1268 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1271 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1272 { title => 'My parents sold me to a record company' ,year => 2005 },
1273 { title => 'Why Am I So Ugly?', year => 2006 },
1274 { title => 'I Got Surgery and am now Popular', year => 2007 }
1279 ## Array Context Example
1280 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1281 { name => "Artist One"},
1282 { name => "Artist Two"},
1283 { name => "Artist Three", cds=> [
1284 { title => "First CD", year => 2007},
1285 { title => "Second CD", year => 2008},
1289 print $ArtistOne->name; ## response is 'Artist One'
1290 print $ArtistThree->cds->count ## reponse is '2'
1295 my ($self, $data) = @_;
1297 if(defined wantarray) {
1299 foreach my $item (@$data) {
1300 push(@created, $self->create($item));
1304 my ($first, @rest) = @$data;
1306 my @names = grep {!ref $first->{$_}} keys %$first;
1307 my @rels = grep { $self->result_source->has_relationship($_) } keys %$first;
1308 my @pks = $self->result_source->primary_columns;
1310 ## do the belongs_to relationships
1311 foreach my $index (0..$#$data) {
1312 if( grep { !defined $data->[$index]->{$_} } @pks ) {
1313 my @ret = $self->populate($data);
1317 foreach my $rel (@rels) {
1318 next unless $data->[$index]->{$rel} && ref $data->[$index]->{$rel} eq "HASH";
1319 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1320 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1321 my $related = $result->result_source->resolve_condition(
1322 $result->result_source->relationship_info($reverse)->{cond},
1327 delete $data->[$index]->{$rel};
1328 $data->[$index] = {%{$data->[$index]}, %$related};
1330 push @names, keys %$related if $index == 0;
1334 ## do bulk insert on current row
1335 my @values = map { [ @$_{@names} ] } @$data;
1337 $self->result_source->storage->insert_bulk(
1338 $self->result_source,
1343 ## do the has_many relationships
1344 foreach my $item (@$data) {
1346 foreach my $rel (@rels) {
1347 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1349 my $parent = $self->find(map {{$_=>$item->{$_}} } @pks)
1350 || $self->throw_exception('Cannot find the relating object.');
1352 my $child = $parent->$rel;
1354 my $related = $child->result_source->resolve_condition(
1355 $parent->result_source->relationship_info($rel)->{cond},
1360 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1361 my @populate = map { {%$_, %$related} } @rows_to_add;
1363 $child->populate( \@populate );
1373 =item Arguments: none
1375 =item Return Value: $pager
1379 Return Value a L<Data::Page> object for the current resultset. Only makes
1380 sense for queries with a C<page> attribute.
1386 my $attrs = $self->{attrs};
1387 $self->throw_exception("Can't create pager for non-paged rs")
1388 unless $self->{attrs}{page};
1389 $attrs->{rows} ||= 10;
1390 return $self->{pager} ||= Data::Page->new(
1391 $self->_count, $attrs->{rows}, $self->{attrs}{page});
1398 =item Arguments: $page_number
1400 =item Return Value: $rs
1404 Returns a resultset for the $page_number page of the resultset on which page
1405 is called, where each page contains a number of rows equal to the 'rows'
1406 attribute set on the resultset (10 by default).
1411 my ($self, $page) = @_;
1412 return (ref $self)->new($self->_source_handle, { %{$self->{attrs}}, page => $page });
1419 =item Arguments: \%vals
1421 =item Return Value: $object
1425 Creates an object in the resultset's result class and returns it.
1430 my ($self, $values) = @_;
1431 $self->throw_exception( "new_result needs a hash" )
1432 unless (ref $values eq 'HASH');
1433 $self->throw_exception(
1434 "Can't abstract implicit construct, condition not a hash"
1435 ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
1437 my $alias = $self->{attrs}{alias};
1438 my $collapsed_cond = $self->{cond} ? $self->_collapse_cond($self->{cond}) : {};
1440 %{ $self->_remove_alias($values, $alias) },
1441 %{ $self->_remove_alias($collapsed_cond, $alias) },
1442 -source_handle => $self->_source_handle,
1443 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
1446 return $self->result_class->new(\%new);
1451 # Recursively collapse the condition.
1453 sub _collapse_cond {
1454 my ($self, $cond, $collapsed) = @_;
1458 if (ref $cond eq 'ARRAY') {
1459 foreach my $subcond (@$cond) {
1460 next unless ref $subcond; # -or
1461 # warn "ARRAY: " . Dumper $subcond;
1462 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1465 elsif (ref $cond eq 'HASH') {
1466 if (keys %$cond and (keys %$cond)[0] eq '-and') {
1467 foreach my $subcond (@{$cond->{-and}}) {
1468 # warn "HASH: " . Dumper $subcond;
1469 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1473 # warn "LEAF: " . Dumper $cond;
1474 foreach my $col (keys %$cond) {
1475 my $value = $cond->{$col};
1476 $collapsed->{$col} = $value;
1486 # Remove the specified alias from the specified query hash. A copy is made so
1487 # the original query is not modified.
1490 my ($self, $query, $alias) = @_;
1492 my %orig = %{ $query || {} };
1495 foreach my $key (keys %orig) {
1497 $unaliased{$key} = $orig{$key};
1500 $unaliased{$1} = $orig{$key}
1501 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
1511 =item Arguments: \%vals, \%attrs?
1513 =item Return Value: $object
1517 Find an existing record from this resultset. If none exists, instantiate a new
1518 result object and return it. The object will not be saved into your storage
1519 until you call L<DBIx::Class::Row/insert> on it.
1521 If you want objects to be saved immediately, use L</find_or_create> instead.
1527 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1528 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1529 my $exists = $self->find($hash, $attrs);
1530 return defined $exists ? $exists : $self->new_result($hash);
1537 =item Arguments: \%vals
1539 =item Return Value: $object
1543 Inserts a record into the resultset and returns the object representing it.
1545 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
1550 my ($self, $attrs) = @_;
1551 $self->throw_exception( "create needs a hashref" )
1552 unless ref $attrs eq 'HASH';
1553 return $self->new_result($attrs)->insert;
1556 =head2 find_or_create
1560 =item Arguments: \%vals, \%attrs?
1562 =item Return Value: $object
1566 $class->find_or_create({ key => $val, ... });
1568 Tries to find a record based on its primary key or unique constraint; if none
1569 is found, creates one and returns that instead.
1571 my $cd = $schema->resultset('CD')->find_or_create({
1573 artist => 'Massive Attack',
1574 title => 'Mezzanine',
1578 Also takes an optional C<key> attribute, to search by a specific key or unique
1579 constraint. For example:
1581 my $cd = $schema->resultset('CD')->find_or_create(
1583 artist => 'Massive Attack',
1584 title => 'Mezzanine',
1586 { key => 'cd_artist_title' }
1589 See also L</find> and L</update_or_create>. For information on how to declare
1590 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1594 sub find_or_create {
1596 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1597 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1598 my $exists = $self->find($hash, $attrs);
1599 return defined $exists ? $exists : $self->create($hash);
1602 =head2 update_or_create
1606 =item Arguments: \%col_values, { key => $unique_constraint }?
1608 =item Return Value: $object
1612 $class->update_or_create({ col => $val, ... });
1614 First, searches for an existing row matching one of the unique constraints
1615 (including the primary key) on the source of this resultset. If a row is
1616 found, updates it with the other given column values. Otherwise, creates a new
1619 Takes an optional C<key> attribute to search on a specific unique constraint.
1622 # In your application
1623 my $cd = $schema->resultset('CD')->update_or_create(
1625 artist => 'Massive Attack',
1626 title => 'Mezzanine',
1629 { key => 'cd_artist_title' }
1632 If no C<key> is specified, it searches on all unique constraints defined on the
1633 source, including the primary key.
1635 If the C<key> is specified as C<primary>, it searches only on the primary key.
1637 See also L</find> and L</find_or_create>. For information on how to declare
1638 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1642 sub update_or_create {
1644 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1645 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
1647 my $row = $self->find($cond, $attrs);
1649 $row->update($cond);
1653 return $self->create($cond);
1660 =item Arguments: none
1662 =item Return Value: \@cache_objects?
1666 Gets the contents of the cache for the resultset, if the cache is set.
1678 =item Arguments: \@cache_objects
1680 =item Return Value: \@cache_objects
1684 Sets the contents of the cache for the resultset. Expects an arrayref
1685 of objects of the same class as those produced by the resultset. Note that
1686 if the cache is set the resultset will return the cached objects rather
1687 than re-querying the database even if the cache attr is not set.
1692 my ( $self, $data ) = @_;
1693 $self->throw_exception("set_cache requires an arrayref")
1694 if defined($data) && (ref $data ne 'ARRAY');
1695 $self->{all_cache} = $data;
1702 =item Arguments: none
1704 =item Return Value: []
1708 Clears the cache for the resultset.
1713 shift->set_cache(undef);
1716 =head2 related_resultset
1720 =item Arguments: $relationship_name
1722 =item Return Value: $resultset
1726 Returns a related resultset for the supplied relationship name.
1728 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
1732 sub related_resultset {
1733 my ($self, $rel) = @_;
1735 $self->{related_resultsets} ||= {};
1736 return $self->{related_resultsets}{$rel} ||= do {
1737 my $rel_obj = $self->result_source->relationship_info($rel);
1739 $self->throw_exception(
1740 "search_related: result source '" . $self->_source_handle->source_moniker .
1741 "' has no such relationship $rel")
1744 my ($from,$seen) = $self->_resolve_from($rel);
1746 my $join_count = $seen->{$rel};
1747 my $alias = ($join_count > 1 ? join('_', $rel, $join_count) : $rel);
1749 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
1750 my %attrs = %{$self->{attrs}||{}};
1751 delete $attrs{result_class};
1755 if (my $cache = $self->get_cache) {
1756 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
1757 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
1762 my $new = $self->_source_handle
1764 ->resultset($rel_obj->{class})
1773 where => $self->{cond},
1777 $new->set_cache($new_cache) if $new_cache;
1783 my ($self, $extra_join) = @_;
1784 my $source = $self->result_source;
1785 my $attrs = $self->{attrs};
1787 my $from = $attrs->{from}
1788 || [ { $attrs->{alias} => $source->from } ];
1790 my $seen = { %{$attrs->{seen_join}||{}} };
1792 my $join = ($attrs->{join}
1793 ? [ $attrs->{join}, $extra_join ]
1796 # we need to take the prefetch the attrs into account before we
1797 # ->resolve_join as otherwise they get lost - captainL
1798 my $merged = $self->_merge_attr( $join, $attrs->{prefetch} );
1802 ($join ? $source->resolve_join($merged, $attrs->{alias}, $seen) : ()),
1805 return ($from,$seen);
1808 sub _resolved_attrs {
1810 return $self->{_attrs} if $self->{_attrs};
1812 my $attrs = { %{$self->{attrs}||{}} };
1813 my $source = $self->result_source;
1814 my $alias = $attrs->{alias};
1816 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
1817 if ($attrs->{columns}) {
1818 delete $attrs->{as};
1819 } elsif (!$attrs->{select}) {
1820 $attrs->{columns} = [ $source->columns ];
1825 ? (ref $attrs->{select} eq 'ARRAY'
1826 ? [ @{$attrs->{select}} ]
1827 : [ $attrs->{select} ])
1828 : [ map { m/\./ ? $_ : "${alias}.$_" } @{delete $attrs->{columns}} ]
1832 ? (ref $attrs->{as} eq 'ARRAY'
1833 ? [ @{$attrs->{as}} ]
1835 : [ map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{$attrs->{select}} ]
1839 if ($adds = delete $attrs->{include_columns}) {
1840 $adds = [$adds] unless ref $adds eq 'ARRAY';
1841 push(@{$attrs->{select}}, @$adds);
1842 push(@{$attrs->{as}}, map { m/([^.]+)$/; $1 } @$adds);
1844 if ($adds = delete $attrs->{'+select'}) {
1845 $adds = [$adds] unless ref $adds eq 'ARRAY';
1846 push(@{$attrs->{select}},
1847 map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds);
1849 if (my $adds = delete $attrs->{'+as'}) {
1850 $adds = [$adds] unless ref $adds eq 'ARRAY';
1851 push(@{$attrs->{as}}, @$adds);
1854 $attrs->{from} ||= [ { 'me' => $source->from } ];
1856 if (exists $attrs->{join} || exists $attrs->{prefetch}) {
1857 my $join = delete $attrs->{join} || {};
1859 if (defined $attrs->{prefetch}) {
1860 $join = $self->_merge_attr(
1861 $join, $attrs->{prefetch}
1866 $attrs->{from} = # have to copy here to avoid corrupting the original
1869 $source->resolve_join($join, $alias, { %{$attrs->{seen_join}||{}} })
1874 $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct};
1875 if ($attrs->{order_by}) {
1876 $attrs->{order_by} = (ref($attrs->{order_by}) eq 'ARRAY'
1877 ? [ @{$attrs->{order_by}} ]
1878 : [ $attrs->{order_by} ]);
1880 $attrs->{order_by} = [];
1883 my $collapse = $attrs->{collapse} || {};
1884 if (my $prefetch = delete $attrs->{prefetch}) {
1885 $prefetch = $self->_merge_attr({}, $prefetch);
1887 my $seen = $attrs->{seen_join} || {};
1888 foreach my $p (ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch)) {
1889 # bring joins back to level of current class
1890 my @prefetch = $source->resolve_prefetch(
1891 $p, $alias, $seen, \@pre_order, $collapse
1893 push(@{$attrs->{select}}, map { $_->[0] } @prefetch);
1894 push(@{$attrs->{as}}, map { $_->[1] } @prefetch);
1896 push(@{$attrs->{order_by}}, @pre_order);
1898 $attrs->{collapse} = $collapse;
1900 if ($attrs->{page}) {
1901 $attrs->{offset} ||= 0;
1902 $attrs->{offset} += ($attrs->{rows} * ($attrs->{page} - 1));
1905 return $self->{_attrs} = $attrs;
1909 my ($self, $attr) = @_;
1911 if (ref $attr eq 'HASH') {
1912 return $self->_rollout_hash($attr);
1913 } elsif (ref $attr eq 'ARRAY') {
1914 return $self->_rollout_array($attr);
1920 sub _rollout_array {
1921 my ($self, $attr) = @_;
1924 foreach my $element (@{$attr}) {
1925 if (ref $element eq 'HASH') {
1926 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
1927 } elsif (ref $element eq 'ARRAY') {
1928 # XXX - should probably recurse here
1929 push( @rolled_array, @{$self->_rollout_array($element)} );
1931 push( @rolled_array, $element );
1934 return \@rolled_array;
1938 my ($self, $attr) = @_;
1941 foreach my $key (keys %{$attr}) {
1942 push( @rolled_array, { $key => $attr->{$key} } );
1944 return \@rolled_array;
1947 sub _calculate_score {
1948 my ($self, $a, $b) = @_;
1950 if (ref $b eq 'HASH') {
1951 my ($b_key) = keys %{$b};
1952 if (ref $a eq 'HASH') {
1953 my ($a_key) = keys %{$a};
1954 if ($a_key eq $b_key) {
1955 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
1960 return ($a eq $b_key) ? 1 : 0;
1963 if (ref $a eq 'HASH') {
1964 my ($a_key) = keys %{$a};
1965 return ($b eq $a_key) ? 1 : 0;
1967 return ($b eq $a) ? 1 : 0;
1973 my ($self, $a, $b) = @_;
1975 return $b unless defined($a);
1976 return $a unless defined($b);
1978 $a = $self->_rollout_attr($a);
1979 $b = $self->_rollout_attr($b);
1982 foreach my $b_element ( @{$b} ) {
1983 # find best candidate from $a to merge $b_element into
1984 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
1985 foreach my $a_element ( @{$a} ) {
1986 my $score = $self->_calculate_score( $a_element, $b_element );
1987 if ($score > $best_candidate->{score}) {
1988 $best_candidate->{position} = $position;
1989 $best_candidate->{score} = $score;
1993 my ($b_key) = ( ref $b_element eq 'HASH' ) ? keys %{$b_element} : ($b_element);
1994 if ($best_candidate->{score} == 0 || exists $seen_keys->{$b_key}) {
1995 push( @{$a}, $b_element );
1997 $seen_keys->{$b_key} = 1; # don't merge the same key twice
1998 my $a_best = $a->[$best_candidate->{position}];
1999 # merge a_best and b_element together and replace original with merged
2000 if (ref $a_best ne 'HASH') {
2001 $a->[$best_candidate->{position}] = $b_element;
2002 } elsif (ref $b_element eq 'HASH') {
2003 my ($key) = keys %{$a_best};
2004 $a->[$best_candidate->{position}] = { $key => $self->_merge_attr($a_best->{$key}, $b_element->{$key}) };
2016 $self->_source_handle($_[0]->handle);
2018 $self->_source_handle->resolve;
2022 =head2 throw_exception
2024 See L<DBIx::Class::Schema/throw_exception> for details.
2028 sub throw_exception {
2030 $self->_source_handle->schema->throw_exception(@_);
2033 # XXX: FIXME: Attributes docs need clearing up
2037 The resultset takes various attributes that modify its behavior. Here's an
2044 =item Value: ($order_by | \@order_by)
2048 Which column(s) to order the results by. This is currently passed
2049 through directly to SQL, so you can give e.g. C<year DESC> for a
2050 descending order on the column `year'.
2052 Please note that if you have C<quote_char> enabled (see
2053 L<DBIx::Class::Storage::DBI/connect_info>) you will need to do C<\'year DESC' > to
2054 specify an order. (The scalar ref causes it to be passed as raw sql to the DB,
2055 so you will need to manually quote things as appropriate.)
2061 =item Value: \@columns
2065 Shortcut to request a particular set of columns to be retrieved. Adds
2066 C<me.> onto the start of any column without a C<.> in it and sets C<select>
2067 from that, then auto-populates C<as> from C<select> as normal. (You may also
2068 use the C<cols> attribute, as in earlier versions of DBIC.)
2070 =head2 include_columns
2074 =item Value: \@columns
2078 Shortcut to include additional columns in the returned results - for example
2080 $schema->resultset('CD')->search(undef, {
2081 include_columns => ['artist.name'],
2085 would return all CDs and include a 'name' column to the information
2086 passed to object inflation. Note that the 'artist' is the name of the
2087 column (or relationship) accessor, and 'name' is the name of the column
2088 accessor in the related table.
2094 =item Value: \@select_columns
2098 Indicates which columns should be selected from the storage. You can use
2099 column names, or in the case of RDBMS back ends, function or stored procedure
2102 $rs = $schema->resultset('Employee')->search(undef, {
2105 { count => 'employeeid' },
2110 When you use function/stored procedure names and do not supply an C<as>
2111 attribute, the column names returned are storage-dependent. E.g. MySQL would
2112 return a column named C<count(employeeid)> in the above example.
2118 Indicates additional columns to be selected from storage. Works the same as
2119 L<select> but adds columns to the selection.
2127 Indicates additional column names for those added via L<+select>.
2135 =item Value: \@inflation_names
2139 Indicates column names for object inflation. That is, c< as >
2140 indicates the name that the column can be accessed as via the
2141 C<get_column> method (or via the object accessor, B<if one already
2142 exists>). It has nothing to do with the SQL code C< SELECT foo AS bar
2145 The C< as > attribute is used in conjunction with C<select>,
2146 usually when C<select> contains one or more function or stored
2149 $rs = $schema->resultset('Employee')->search(undef, {
2152 { count => 'employeeid' }
2154 as => ['name', 'employee_count'],
2157 my $employee = $rs->first(); # get the first Employee
2159 If the object against which the search is performed already has an accessor
2160 matching a column name specified in C<as>, the value can be retrieved using
2161 the accessor as normal:
2163 my $name = $employee->name();
2165 If on the other hand an accessor does not exist in the object, you need to
2166 use C<get_column> instead:
2168 my $employee_count = $employee->get_column('employee_count');
2170 You can create your own accessors if required - see
2171 L<DBIx::Class::Manual::Cookbook> for details.
2173 Please note: This will NOT insert an C<AS employee_count> into the SQL
2174 statement produced, it is used for internal access only. Thus
2175 attempting to use the accessor in an C<order_by> clause or similar
2176 will fail miserably.
2178 To get around this limitation, you can supply literal SQL to your
2179 C<select> attibute that contains the C<AS alias> text, eg:
2181 select => [\'myfield AS alias']
2187 =item Value: ($rel_name | \@rel_names | \%rel_names)
2191 Contains a list of relationships that should be joined for this query. For
2194 # Get CDs by Nine Inch Nails
2195 my $rs = $schema->resultset('CD')->search(
2196 { 'artist.name' => 'Nine Inch Nails' },
2197 { join => 'artist' }
2200 Can also contain a hash reference to refer to the other relation's relations.
2203 package MyApp::Schema::Track;
2204 use base qw/DBIx::Class/;
2205 __PACKAGE__->table('track');
2206 __PACKAGE__->add_columns(qw/trackid cd position title/);
2207 __PACKAGE__->set_primary_key('trackid');
2208 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
2211 # In your application
2212 my $rs = $schema->resultset('Artist')->search(
2213 { 'track.title' => 'Teardrop' },
2215 join => { cd => 'track' },
2216 order_by => 'artist.name',
2220 You need to use the relationship (not the table) name in conditions,
2221 because they are aliased as such. The current table is aliased as "me", so
2222 you need to use me.column_name in order to avoid ambiguity. For example:
2224 # Get CDs from 1984 with a 'Foo' track
2225 my $rs = $schema->resultset('CD')->search(
2228 'tracks.name' => 'Foo'
2230 { join => 'tracks' }
2233 If the same join is supplied twice, it will be aliased to <rel>_2 (and
2234 similarly for a third time). For e.g.
2236 my $rs = $schema->resultset('Artist')->search({
2237 'cds.title' => 'Down to Earth',
2238 'cds_2.title' => 'Popular',
2240 join => [ qw/cds cds/ ],
2243 will return a set of all artists that have both a cd with title 'Down
2244 to Earth' and a cd with title 'Popular'.
2246 If you want to fetch related objects from other tables as well, see C<prefetch>
2253 =item Value: ($rel_name | \@rel_names | \%rel_names)
2257 Contains one or more relationships that should be fetched along with the main
2258 query (when they are accessed afterwards they will have already been
2259 "prefetched"). This is useful for when you know you will need the related
2260 objects, because it saves at least one query:
2262 my $rs = $schema->resultset('Tag')->search(
2271 The initial search results in SQL like the following:
2273 SELECT tag.*, cd.*, artist.* FROM tag
2274 JOIN cd ON tag.cd = cd.cdid
2275 JOIN artist ON cd.artist = artist.artistid
2277 L<DBIx::Class> has no need to go back to the database when we access the
2278 C<cd> or C<artist> relationships, which saves us two SQL statements in this
2281 Simple prefetches will be joined automatically, so there is no need
2282 for a C<join> attribute in the above search. If you're prefetching to
2283 depth (e.g. { cd => { artist => 'label' } or similar), you'll need to
2284 specify the join as well.
2286 C<prefetch> can be used with the following relationship types: C<belongs_to>,
2287 C<has_one> (or if you're using C<add_relationship>, any relationship declared
2288 with an accessor type of 'single' or 'filter').
2298 Makes the resultset paged and specifies the page to retrieve. Effectively
2299 identical to creating a non-pages resultset and then calling ->page($page)
2302 If L<rows> attribute is not specified it defualts to 10 rows per page.
2312 Specifes the maximum number of rows for direct retrieval or the number of
2313 rows per page if the page attribute or method is used.
2319 =item Value: $offset
2323 Specifies the (zero-based) row number for the first row to be returned, or the
2324 of the first row of the first page if paging is used.
2330 =item Value: \@columns
2334 A arrayref of columns to group by. Can include columns of joined tables.
2336 group_by => [qw/ column1 column2 ... /]
2342 =item Value: $condition
2346 HAVING is a select statement attribute that is applied between GROUP BY and
2347 ORDER BY. It is applied to the after the grouping calculations have been
2350 having => { 'count(employee)' => { '>=', 100 } }
2356 =item Value: (0 | 1)
2360 Set to 1 to group by all columns.
2366 Adds to the WHERE clause.
2368 # only return rows WHERE deleted IS NULL for all searches
2369 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
2371 Can be overridden by passing C<{ where => undef }> as an attribute
2378 Set to 1 to cache search results. This prevents extra SQL queries if you
2379 revisit rows in your ResultSet:
2381 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
2383 while( my $artist = $resultset->next ) {
2387 $rs->first; # without cache, this would issue a query
2389 By default, searches are not cached.
2391 For more examples of using these attributes, see
2392 L<DBIx::Class::Manual::Cookbook>.
2398 =item Value: \@from_clause
2402 The C<from> attribute gives you manual control over the C<FROM> clause of SQL
2403 statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
2406 NOTE: Use this on your own risk. This allows you to shoot off your foot!
2408 C<join> will usually do what you need and it is strongly recommended that you
2409 avoid using C<from> unless you cannot achieve the desired result using C<join>.
2410 And we really do mean "cannot", not just tried and failed. Attempting to use
2411 this because you're having problems with C<join> is like trying to use x86
2412 ASM because you've got a syntax error in your C. Trust us on this.
2414 Now, if you're still really, really sure you need to use this (and if you're
2415 not 100% sure, ask the mailing list first), here's an explanation of how this
2418 The syntax is as follows -
2421 { <alias1> => <table1> },
2423 { <alias2> => <table2>, -join_type => 'inner|left|right' },
2424 [], # nested JOIN (optional)
2425 { <table1.column1> => <table2.column2>, ... (more conditions) },
2427 # More of the above [ ] may follow for additional joins
2434 ON <table1.column1> = <table2.column2>
2435 <more joins may follow>
2437 An easy way to follow the examples below is to remember the following:
2439 Anything inside "[]" is a JOIN
2440 Anything inside "{}" is a condition for the enclosing JOIN
2442 The following examples utilize a "person" table in a family tree application.
2443 In order to express parent->child relationships, this table is self-joined:
2445 # Person->belongs_to('father' => 'Person');
2446 # Person->belongs_to('mother' => 'Person');
2448 C<from> can be used to nest joins. Here we return all children with a father,
2449 then search against all mothers of those children:
2451 $rs = $schema->resultset('Person')->search(
2454 alias => 'mother', # alias columns in accordance with "from"
2456 { mother => 'person' },
2459 { child => 'person' },
2461 { father => 'person' },
2462 { 'father.person_id' => 'child.father_id' }
2465 { 'mother.person_id' => 'child.mother_id' }
2472 # SELECT mother.* FROM person mother
2475 # JOIN person father
2476 # ON ( father.person_id = child.father_id )
2478 # ON ( mother.person_id = child.mother_id )
2480 The type of any join can be controlled manually. To search against only people
2481 with a father in the person table, we could explicitly use C<INNER JOIN>:
2483 $rs = $schema->resultset('Person')->search(
2486 alias => 'child', # alias columns in accordance with "from"
2488 { child => 'person' },
2490 { father => 'person', -join_type => 'inner' },
2491 { 'father.id' => 'child.father_id' }
2498 # SELECT child.* FROM person child
2499 # INNER JOIN person father ON child.father_id = father.id