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');
55 If a resultset is used as a number it returns the C<count()>. However, if it is used as a boolean it is always true. So if you want to check if a result set has any results use C<if $rs != 0>. C<if $rs> will always be true.
63 =item Arguments: $source, \%$attrs
65 =item Return Value: $rs
69 The resultset constructor. Takes a source object (usually a
70 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
71 L</ATTRIBUTES> below). Does not perform any queries -- these are
72 executed as needed by the other methods.
74 Generally you won't need to construct a resultset manually. You'll
75 automatically get one from e.g. a L</search> called in scalar context:
77 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
79 IMPORTANT: If called on an object, proxies to new_result instead so
81 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
83 will return a CD object, not a ResultSet.
89 return $class->new_result(@_) if ref $class;
91 my ($source, $attrs) = @_;
92 $source = $source->handle
93 unless $source->isa('DBIx::Class::ResultSourceHandle');
94 $attrs = { %{$attrs||{}} };
97 $attrs->{rows} ||= 10;
100 $attrs->{alias} ||= 'me';
103 _source_handle => $source,
104 result_class => $attrs->{result_class} || $source->resolve->result_class,
105 cond => $attrs->{where},
120 =item Arguments: $cond, \%attrs?
122 =item Return Value: $resultset (scalar context), @row_objs (list context)
126 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
127 my $new_rs = $cd_rs->search({ year => 2005 });
129 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
130 # year = 2005 OR year = 2004
132 If you need to pass in additional attributes but no additional condition,
133 call it as C<search(undef, \%attrs)>.
135 # "SELECT name, artistid FROM $artist_table"
136 my @all_artists = $schema->resultset('Artist')->search(undef, {
137 columns => [qw/name artistid/],
140 For a list of attributes that can be passed to C<search>, see
141 L</ATTRIBUTES>. For more examples of using this function, see
142 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
143 documentation for the first argument, see L<SQL::Abstract>.
149 my $rs = $self->search_rs( @_ );
150 return (wantarray ? $rs->all : $rs);
157 =item Arguments: $cond, \%attrs?
159 =item Return Value: $resultset
163 This method does the same exact thing as search() except it will
164 always return a resultset, even in list context.
173 unless (@_) { # no search, effectively just a clone
174 $rows = $self->get_cache;
178 $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
179 my $our_attrs = { %{$self->{attrs}} };
180 my $having = delete $our_attrs->{having};
181 my $where = delete $our_attrs->{where};
183 my $new_attrs = { %{$our_attrs}, %{$attrs} };
185 # merge new attrs into inherited
186 foreach my $key (qw/join prefetch/) {
187 next unless exists $attrs->{$key};
188 $new_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key});
193 (@_ == 1 || ref $_[0] eq "HASH")
195 (ref $_[0] eq 'HASH')
197 (keys %{ $_[0] } > 0)
205 ? $self->throw_exception("Odd number of arguments to search")
212 if (defined $where) {
213 $new_attrs->{where} = (
214 defined $new_attrs->{where}
217 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
218 } $where, $new_attrs->{where}
225 $new_attrs->{where} = (
226 defined $new_attrs->{where}
229 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
230 } $cond, $new_attrs->{where}
236 if (defined $having) {
237 $new_attrs->{having} = (
238 defined $new_attrs->{having}
241 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
242 } $having, $new_attrs->{having}
248 my $rs = (ref $self)->new($self->result_source, $new_attrs);
250 $rs->set_cache($rows);
255 =head2 search_literal
259 =item Arguments: $sql_fragment, @bind_values
261 =item Return Value: $resultset (scalar context), @row_objs (list context)
265 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
266 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
268 Pass a literal chunk of SQL to be added to the conditional part of the
274 my ($self, $cond, @vals) = @_;
275 my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {});
276 $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ];
277 return $self->search(\$cond, $attrs);
284 =item Arguments: @values | \%cols, \%attrs?
286 =item Return Value: $row_object
290 Finds a row based on its primary key or unique constraint. For example, to find
291 a row by its primary key:
293 my $cd = $schema->resultset('CD')->find(5);
295 You can also find a row by a specific unique constraint using the C<key>
296 attribute. For example:
298 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
299 key => 'cd_artist_title'
302 Additionally, you can specify the columns explicitly by name:
304 my $cd = $schema->resultset('CD')->find(
306 artist => 'Massive Attack',
307 title => 'Mezzanine',
309 { key => 'cd_artist_title' }
312 If the C<key> is specified as C<primary>, it searches only on the primary key.
314 If no C<key> is specified, it searches on all unique constraints defined on the
315 source, including the primary key.
317 If your table does not have a primary key, you B<must> provide a value for the
318 C<key> attribute matching one of the unique constraints on the source.
320 See also L</find_or_create> and L</update_or_create>. For information on how to
321 declare unique constraints, see
322 L<DBIx::Class::ResultSource/add_unique_constraint>.
328 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
330 # Default to the primary key, but allow a specific key
331 my @cols = exists $attrs->{key}
332 ? $self->result_source->unique_constraint_columns($attrs->{key})
333 : $self->result_source->primary_columns;
334 $self->throw_exception(
335 "Can't find unless a primary key is defined or unique constraint is specified"
338 # Parse out a hashref from input
340 if (ref $_[0] eq 'HASH') {
341 $input_query = { %{$_[0]} };
343 elsif (@_ == @cols) {
345 @{$input_query}{@cols} = @_;
348 # Compatibility: Allow e.g. find(id => $value)
349 carp "Find by key => value deprecated; please use a hashref instead";
353 my (%related, $info);
355 KEY: foreach my $key (keys %$input_query) {
356 if (ref($input_query->{$key})
357 && ($info = $self->result_source->relationship_info($key))) {
358 my $val = delete $input_query->{$key};
359 next KEY if (ref($val) eq 'ARRAY'); # has_many for multi_create
360 my $rel_q = $self->result_source->resolve_condition(
361 $info->{cond}, $val, $key
363 die "Can't handle OR join condition in find" if ref($rel_q) eq 'ARRAY';
364 @related{keys %$rel_q} = values %$rel_q;
367 if (my @keys = keys %related) {
368 @{$input_query}{@keys} = values %related;
371 my @unique_queries = $self->_unique_queries($input_query, $attrs);
373 # Build the final query: Default to the disjunction of the unique queries,
374 # but allow the input query in case the ResultSet defines the query or the
375 # user is abusing find
376 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
377 my $query = @unique_queries
378 ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
379 : $self->_add_alias($input_query, $alias);
383 my $rs = $self->search($query, $attrs);
384 return keys %{$rs->_resolved_attrs->{collapse}} ? $rs->next : $rs->single;
387 return keys %{$self->_resolved_attrs->{collapse}}
388 ? $self->search($query)->next
389 : $self->single($query);
395 # Add the specified alias to the specified query hash. A copy is made so the
396 # original query is not modified.
399 my ($self, $query, $alias) = @_;
401 my %aliased = %$query;
402 foreach my $col (grep { ! m/\./ } keys %aliased) {
403 $aliased{"$alias.$col"} = delete $aliased{$col};
411 # Build a list of queries which satisfy unique constraints.
413 sub _unique_queries {
414 my ($self, $query, $attrs) = @_;
416 my @constraint_names = exists $attrs->{key}
418 : $self->result_source->unique_constraint_names;
420 my $where = $self->_collapse_cond($self->{attrs}{where} || {});
421 my $num_where = scalar keys %$where;
424 foreach my $name (@constraint_names) {
425 my @unique_cols = $self->result_source->unique_constraint_columns($name);
426 my $unique_query = $self->_build_unique_query($query, \@unique_cols);
428 my $num_cols = scalar @unique_cols;
429 my $num_query = scalar keys %$unique_query;
431 my $total = $num_query + $num_where;
432 if ($num_query && ($num_query == $num_cols || $total == $num_cols)) {
433 # The query is either unique on its own or is unique in combination with
434 # the existing where clause
435 push @unique_queries, $unique_query;
439 return @unique_queries;
442 # _build_unique_query
444 # Constrain the specified query hash based on the specified column names.
446 sub _build_unique_query {
447 my ($self, $query, $unique_cols) = @_;
450 map { $_ => $query->{$_} }
451 grep { exists $query->{$_} }
456 =head2 search_related
460 =item Arguments: $rel, $cond, \%attrs?
462 =item Return Value: $new_resultset
466 $new_rs = $cd_rs->search_related('artist', {
470 Searches the specified relationship, optionally specifying a condition and
471 attributes for matching records. See L</ATTRIBUTES> for more information.
476 return shift->related_resultset(shift)->search(@_);
483 =item Arguments: none
485 =item Return Value: $cursor
489 Returns a storage-driven cursor to the given resultset. See
490 L<DBIx::Class::Cursor> for more information.
497 my $attrs = { %{$self->_resolved_attrs} };
498 return $self->{cursor}
499 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
500 $attrs->{where},$attrs);
507 =item Arguments: $cond?
509 =item Return Value: $row_object?
513 my $cd = $schema->resultset('CD')->single({ year => 2001 });
515 Inflates the first result without creating a cursor if the resultset has
516 any records in it; if not returns nothing. Used by L</find> as an optimisation.
518 Can optionally take an additional condition *only* - this is a fast-code-path
519 method; if you need to add extra joins or similar call ->search and then
520 ->single without a condition on the $rs returned from that.
525 my ($self, $where) = @_;
526 my $attrs = { %{$self->_resolved_attrs} };
528 if (defined $attrs->{where}) {
531 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
532 $where, delete $attrs->{where} ]
535 $attrs->{where} = $where;
539 # XXX: Disabled since it doesn't infer uniqueness in all cases
540 # unless ($self->_is_unique_query($attrs->{where})) {
541 # carp "Query not guaranteed to return a single row"
542 # . "; please declare your unique constraints or use search instead";
545 my @data = $self->result_source->storage->select_single(
546 $attrs->{from}, $attrs->{select},
547 $attrs->{where}, $attrs
550 return (@data ? ($self->_construct_object(@data))[0] : undef);
555 # Try to determine if the specified query is guaranteed to be unique, based on
556 # the declared unique constraints.
558 sub _is_unique_query {
559 my ($self, $query) = @_;
561 my $collapsed = $self->_collapse_query($query);
562 my $alias = $self->{attrs}{alias};
564 foreach my $name ($self->result_source->unique_constraint_names) {
565 my @unique_cols = map {
567 } $self->result_source->unique_constraint_columns($name);
569 # Count the values for each unique column
570 my %seen = map { $_ => 0 } @unique_cols;
572 foreach my $key (keys %$collapsed) {
573 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
574 next unless exists $seen{$aliased}; # Additional constraints are okay
575 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
578 # If we get 0 or more than 1 value for a column, it's not necessarily unique
579 return 1 unless grep { $_ != 1 } values %seen;
587 # Recursively collapse the query, accumulating values for each column.
589 sub _collapse_query {
590 my ($self, $query, $collapsed) = @_;
594 if (ref $query eq 'ARRAY') {
595 foreach my $subquery (@$query) {
596 next unless ref $subquery; # -or
597 # warn "ARRAY: " . Dumper $subquery;
598 $collapsed = $self->_collapse_query($subquery, $collapsed);
601 elsif (ref $query eq 'HASH') {
602 if (keys %$query and (keys %$query)[0] eq '-and') {
603 foreach my $subquery (@{$query->{-and}}) {
604 # warn "HASH: " . Dumper $subquery;
605 $collapsed = $self->_collapse_query($subquery, $collapsed);
609 # warn "LEAF: " . Dumper $query;
610 foreach my $col (keys %$query) {
611 my $value = $query->{$col};
612 $collapsed->{$col}{$value}++;
624 =item Arguments: $cond?
626 =item Return Value: $resultsetcolumn
630 my $max_length = $rs->get_column('length')->max;
632 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
637 my ($self, $column) = @_;
638 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
646 =item Arguments: $cond, \%attrs?
648 =item Return Value: $resultset (scalar context), @row_objs (list context)
652 # WHERE title LIKE '%blue%'
653 $cd_rs = $rs->search_like({ title => '%blue%'});
655 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
656 that this is simply a convenience method. You most likely want to use
657 L</search> with specific operators.
659 For more information, see L<DBIx::Class::Manual::Cookbook>.
665 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
666 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
667 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
668 return $class->search($query, { %$attrs });
675 =item Arguments: $first, $last
677 =item Return Value: $resultset (scalar context), @row_objs (list context)
681 Returns a resultset or object list representing a subset of elements from the
682 resultset slice is called on. Indexes are from 0, i.e., to get the first
685 my ($one, $two, $three) = $rs->slice(0, 2);
690 my ($self, $min, $max) = @_;
691 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
692 $attrs->{offset} = $self->{attrs}{offset} || 0;
693 $attrs->{offset} += $min;
694 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
695 return $self->search(undef(), $attrs);
696 #my $slice = (ref $self)->new($self->result_source, $attrs);
697 #return (wantarray ? $slice->all : $slice);
704 =item Arguments: none
706 =item Return Value: $result?
710 Returns the next element in the resultset (C<undef> is there is none).
712 Can be used to efficiently iterate over records in the resultset:
714 my $rs = $schema->resultset('CD')->search;
715 while (my $cd = $rs->next) {
719 Note that you need to store the resultset object, and call C<next> on it.
720 Calling C<< resultset('Table')->next >> repeatedly will always return the
721 first record from the resultset.
727 if (my $cache = $self->get_cache) {
728 $self->{all_cache_position} ||= 0;
729 return $cache->[$self->{all_cache_position}++];
731 if ($self->{attrs}{cache}) {
732 $self->{all_cache_position} = 1;
733 return ($self->all)[0];
735 if ($self->{stashed_objects}) {
736 my $obj = shift(@{$self->{stashed_objects}});
737 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
741 exists $self->{stashed_row}
742 ? @{delete $self->{stashed_row}}
743 : $self->cursor->next
745 return undef unless (@row);
746 my ($row, @more) = $self->_construct_object(@row);
747 $self->{stashed_objects} = \@more if @more;
751 sub _construct_object {
752 my ($self, @row) = @_;
753 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row);
754 my @new = $self->result_class->inflate_result($self->result_source, @$info);
755 @new = $self->{_attrs}{record_filter}->(@new)
756 if exists $self->{_attrs}{record_filter};
760 sub _collapse_result {
761 my ($self, $as_proto, $row) = @_;
765 # 'foo' => [ undef, 'foo' ]
766 # 'foo.bar' => [ 'foo', 'bar' ]
767 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
769 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
771 my %collapse = %{$self->{_attrs}{collapse}||{}};
775 # if we're doing collapsing (has_many prefetch) we need to grab records
776 # until the PK changes, so fill @pri_index. if not, we leave it empty so
777 # we know we don't have to bother.
779 # the reason for not using the collapse stuff directly is because if you
780 # had for e.g. two artists in a row with no cds, the collapse info for
781 # both would be NULL (undef) so you'd lose the second artist
783 # store just the index so we can check the array positions from the row
784 # without having to contruct the full hash
786 if (keys %collapse) {
787 my %pri = map { ($_ => 1) } $self->result_source->primary_columns;
788 foreach my $i (0 .. $#construct_as) {
789 next if defined($construct_as[$i][0]); # only self table
790 if (delete $pri{$construct_as[$i][1]}) {
791 push(@pri_index, $i);
793 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
797 # no need to do an if, it'll be empty if @pri_index is empty anyway
799 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
803 do { # no need to check anything at the front, we always want the first row
807 foreach my $this_as (@construct_as) {
808 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
811 push(@const_rows, \%const);
813 } until ( # no pri_index => no collapse => drop straight out
816 do { # get another row, stash it, drop out if different PK
818 @copy = $self->cursor->next;
819 $self->{stashed_row} = \@copy;
821 # last thing in do block, counts as true if anything doesn't match
823 # check xor defined first for NULL vs. NOT NULL then if one is
824 # defined the other must be so check string equality
827 (defined $pri_vals{$_} ^ defined $copy[$_])
828 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
833 my $alias = $self->{attrs}{alias};
840 foreach my $const (@const_rows) {
841 scalar @const_keys or do {
842 @const_keys = sort { length($a) <=> length($b) } keys %$const;
844 foreach my $key (@const_keys) {
847 my @parts = split(/\./, $key);
849 my $data = $const->{$key};
850 foreach my $p (@parts) {
851 $target = $target->[1]->{$p} ||= [];
853 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
854 # collapsing at this point and on final part
855 my $pos = $collapse_pos{$cur};
856 CK: foreach my $ck (@ckey) {
857 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
858 $collapse_pos{$cur} = $data;
859 delete @collapse_pos{ # clear all positioning for sub-entries
860 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
867 if (exists $collapse{$cur}) {
868 $target = $target->[-1];
871 $target->[0] = $data;
873 $info->[0] = $const->{$key};
885 =item Arguments: $result_source?
887 =item Return Value: $result_source
891 An accessor for the primary ResultSource object from which this ResultSet
898 =item Arguments: $result_class?
900 =item Return Value: $result_class
904 An accessor for the class to use when creating row objects. Defaults to
905 C<< result_source->result_class >> - which in most cases is the name of the
906 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
915 =item Arguments: $cond, \%attrs??
917 =item Return Value: $count
921 Performs an SQL C<COUNT> with the same query as the resultset was built
922 with to find the number of elements. If passed arguments, does a search
923 on the resultset and counts the results of that.
925 Note: When using C<count> with C<group_by>, L<DBIX::Class> emulates C<GROUP BY>
926 using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do
927 not support C<DISTINCT> with multiple columns. If you are using such a
928 database, you should only use columns from the main table in your C<group_by>
935 return $self->search(@_)->count if @_ and defined $_[0];
936 return scalar @{ $self->get_cache } if $self->get_cache;
937 my $count = $self->_count;
938 return 0 unless $count;
940 # need to take offset from resolved attrs
942 $count -= $self->{_attrs}{offset} if $self->{_attrs}{offset};
943 $count = $self->{attrs}{rows} if
944 $self->{attrs}{rows} and $self->{attrs}{rows} < $count;
945 $count = 0 if ($count < 0);
949 sub _count { # Separated out so pager can get the full count
951 my $select = { count => '*' };
953 my $attrs = { %{$self->_resolved_attrs} };
954 if (my $group_by = delete $attrs->{group_by}) {
955 delete $attrs->{having};
956 my @distinct = (ref $group_by ? @$group_by : ($group_by));
957 # todo: try CONCAT for multi-column pk
958 my @pk = $self->result_source->primary_columns;
960 my $alias = $attrs->{alias};
961 foreach my $column (@distinct) {
962 if ($column =~ qr/^(?:\Q${alias}.\E)?$pk[0]$/) {
963 @distinct = ($column);
969 $select = { count => { distinct => \@distinct } };
972 $attrs->{select} = $select;
973 $attrs->{as} = [qw/count/];
975 # offset, order by and page are not needed to count. record_filter is cdbi
976 delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/;
978 my $tmp_rs = (ref $self)->new($self->_source_handle, $attrs);
979 my ($count) = $tmp_rs->cursor->next;
991 =item Arguments: $sql_fragment, @bind_values
993 =item Return Value: $count
997 Counts the results in a literal query. Equivalent to calling L</search_literal>
998 with the passed arguments, then L</count>.
1002 sub count_literal { shift->search_literal(@_)->count; }
1008 =item Arguments: none
1010 =item Return Value: @objects
1014 Returns all elements in the resultset. Called implicitly if the resultset
1015 is returned in list context.
1021 return @{ $self->get_cache } if $self->get_cache;
1025 # TODO: don't call resolve here
1026 if (keys %{$self->_resolved_attrs->{collapse}}) {
1027 # if ($self->{attrs}{prefetch}) {
1028 # Using $self->cursor->all is really just an optimisation.
1029 # If we're collapsing has_many prefetches it probably makes
1030 # very little difference, and this is cleaner than hacking
1031 # _construct_object to survive the approach
1032 my @row = $self->cursor->next;
1034 push(@obj, $self->_construct_object(@row));
1035 @row = (exists $self->{stashed_row}
1036 ? @{delete $self->{stashed_row}}
1037 : $self->cursor->next);
1040 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1043 $self->set_cache(\@obj) if $self->{attrs}{cache};
1051 =item Arguments: none
1053 =item Return Value: $self
1057 Resets the resultset's cursor, so you can iterate through the elements again.
1063 delete $self->{_attrs} if exists $self->{_attrs};
1064 $self->{all_cache_position} = 0;
1065 $self->cursor->reset;
1073 =item Arguments: none
1075 =item Return Value: $object?
1079 Resets the resultset and returns an object for the first result (if the
1080 resultset returns anything).
1085 return $_[0]->reset->next;
1088 # _cond_for_update_delete
1090 # update/delete require the condition to be modified to handle
1091 # the differing SQL syntax available. This transforms the $self->{cond}
1092 # appropriately, returning the new condition.
1094 sub _cond_for_update_delete {
1095 my ($self, $full_cond) = @_;
1098 $full_cond ||= $self->{cond};
1099 # No-op. No condition, we're updating/deleting everything
1100 return $cond unless ref $full_cond;
1102 if (ref $full_cond eq 'ARRAY') {
1106 foreach my $key (keys %{$_}) {
1108 $hash{$1} = $_->{$key};
1114 elsif (ref $full_cond eq 'HASH') {
1115 if ((keys %{$full_cond})[0] eq '-and') {
1118 my @cond = @{$full_cond->{-and}};
1119 for (my $i = 0; $i < @cond; $i++) {
1120 my $entry = $cond[$i];
1123 if (ref $entry eq 'HASH') {
1124 $hash = $self->_cond_for_update_delete($entry);
1127 $entry =~ /([^.]+)$/;
1128 $hash->{$1} = $cond[++$i];
1131 push @{$cond->{-and}}, $hash;
1135 foreach my $key (keys %{$full_cond}) {
1137 $cond->{$1} = $full_cond->{$key};
1142 $self->throw_exception(
1143 "Can't update/delete on resultset with condition unless hash or array"
1155 =item Arguments: \%values
1157 =item Return Value: $storage_rv
1161 Sets the specified columns in the resultset to the supplied values in a
1162 single query. Return value will be true if the update succeeded or false
1163 if no records were updated; exact type of success value is storage-dependent.
1168 my ($self, $values) = @_;
1169 $self->throw_exception("Values for update must be a hash")
1170 unless ref $values eq 'HASH';
1172 my $cond = $self->_cond_for_update_delete;
1174 return $self->result_source->storage->update(
1175 $self->result_source, $values, $cond
1183 =item Arguments: \%values
1185 =item Return Value: 1
1189 Fetches all objects and updates them one at a time. Note that C<update_all>
1190 will run DBIC cascade triggers, while L</update> will not.
1195 my ($self, $values) = @_;
1196 $self->throw_exception("Values for update must be a hash")
1197 unless ref $values eq 'HASH';
1198 foreach my $obj ($self->all) {
1199 $obj->set_columns($values)->update;
1208 =item Arguments: none
1210 =item Return Value: 1
1214 Deletes the contents of the resultset from its result source. Note that this
1215 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1216 to run. See also L<DBIx::Class::Row/delete>.
1223 my $cond = $self->_cond_for_update_delete;
1225 $self->result_source->storage->delete($self->result_source, $cond);
1233 =item Arguments: none
1235 =item Return Value: 1
1239 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1240 will run DBIC cascade triggers, while L</delete> will not.
1246 $_->delete for $self->all;
1254 =item Arguments: \@data;
1258 Pass an arrayref of hashrefs. Each hashref should be a structure suitable for
1259 submitting to a $resultset->create(...) method.
1261 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1262 to insert the data, as this is a faster method.
1264 Otherwise, each set of data is inserted into the database using
1265 L<DBIx::Class::ResultSet/create>, and a arrayref of the resulting row
1266 objects is returned.
1268 Example: Assuming an Artist Class that has many CDs Classes relating:
1270 my $Artist_rs = $schema->resultset("Artist");
1272 ## Void Context Example
1273 $Artist_rs->populate([
1274 { artistid => 4, name => 'Manufactured Crap', cds => [
1275 { title => 'My First CD', year => 2006 },
1276 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1279 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1280 { title => 'My parents sold me to a record company' ,year => 2005 },
1281 { title => 'Why Am I So Ugly?', year => 2006 },
1282 { title => 'I Got Surgery and am now Popular', year => 2007 }
1287 ## Array Context Example
1288 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1289 { name => "Artist One"},
1290 { name => "Artist Two"},
1291 { name => "Artist Three", cds=> [
1292 { title => "First CD", year => 2007},
1293 { title => "Second CD", year => 2008},
1297 print $ArtistOne->name; ## response is 'Artist One'
1298 print $ArtistThree->cds->count ## reponse is '2'
1303 my ($self, $data) = @_;
1305 if(defined wantarray) {
1307 foreach my $item (@$data) {
1308 push(@created, $self->create($item));
1312 my ($first, @rest) = @$data;
1314 my @names = grep {!ref $first->{$_}} keys %$first;
1315 my @rels = grep { $self->result_source->has_relationship($_) } keys %$first;
1316 my @pks = $self->result_source->primary_columns;
1318 ## do the belongs_to relationships
1319 foreach my $index (0..$#$data) {
1320 if( grep { !defined $data->[$index]->{$_} } @pks ) {
1321 my @ret = $self->populate($data);
1325 foreach my $rel (@rels) {
1326 next unless $data->[$index]->{$rel} && ref $data->[$index]->{$rel} eq "HASH";
1327 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1328 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1329 my $related = $result->result_source->resolve_condition(
1330 $result->result_source->relationship_info($reverse)->{cond},
1335 delete $data->[$index]->{$rel};
1336 $data->[$index] = {%{$data->[$index]}, %$related};
1338 push @names, keys %$related if $index == 0;
1342 ## do bulk insert on current row
1343 my @values = map { [ @$_{@names} ] } @$data;
1345 $self->result_source->storage->insert_bulk(
1346 $self->result_source,
1351 ## do the has_many relationships
1352 foreach my $item (@$data) {
1354 foreach my $rel (@rels) {
1355 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1357 my $parent = $self->find(map {{$_=>$item->{$_}} } @pks)
1358 || $self->throw_exception('Cannot find the relating object.');
1360 my $child = $parent->$rel;
1362 my $related = $child->result_source->resolve_condition(
1363 $parent->result_source->relationship_info($rel)->{cond},
1368 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1369 my @populate = map { {%$_, %$related} } @rows_to_add;
1371 $child->populate( \@populate );
1381 =item Arguments: none
1383 =item Return Value: $pager
1387 Return Value a L<Data::Page> object for the current resultset. Only makes
1388 sense for queries with a C<page> attribute.
1394 my $attrs = $self->{attrs};
1395 $self->throw_exception("Can't create pager for non-paged rs")
1396 unless $self->{attrs}{page};
1397 $attrs->{rows} ||= 10;
1398 return $self->{pager} ||= Data::Page->new(
1399 $self->_count, $attrs->{rows}, $self->{attrs}{page});
1406 =item Arguments: $page_number
1408 =item Return Value: $rs
1412 Returns a resultset for the $page_number page of the resultset on which page
1413 is called, where each page contains a number of rows equal to the 'rows'
1414 attribute set on the resultset (10 by default).
1419 my ($self, $page) = @_;
1420 return (ref $self)->new($self->_source_handle, { %{$self->{attrs}}, page => $page });
1427 =item Arguments: \%vals
1429 =item Return Value: $object
1433 Creates an object in the resultset's result class and returns it.
1438 my ($self, $values) = @_;
1439 $self->throw_exception( "new_result needs a hash" )
1440 unless (ref $values eq 'HASH');
1441 $self->throw_exception(
1442 "Can't abstract implicit construct, condition not a hash"
1443 ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
1445 my $alias = $self->{attrs}{alias};
1446 my $collapsed_cond = $self->{cond} ? $self->_collapse_cond($self->{cond}) : {};
1448 %{ $self->_remove_alias($values, $alias) },
1449 %{ $self->_remove_alias($collapsed_cond, $alias) },
1450 -source_handle => $self->_source_handle,
1451 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
1454 return $self->result_class->new(\%new);
1459 # Recursively collapse the condition.
1461 sub _collapse_cond {
1462 my ($self, $cond, $collapsed) = @_;
1466 if (ref $cond eq 'ARRAY') {
1467 foreach my $subcond (@$cond) {
1468 next unless ref $subcond; # -or
1469 # warn "ARRAY: " . Dumper $subcond;
1470 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1473 elsif (ref $cond eq 'HASH') {
1474 if (keys %$cond and (keys %$cond)[0] eq '-and') {
1475 foreach my $subcond (@{$cond->{-and}}) {
1476 # warn "HASH: " . Dumper $subcond;
1477 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1481 # warn "LEAF: " . Dumper $cond;
1482 foreach my $col (keys %$cond) {
1483 my $value = $cond->{$col};
1484 $collapsed->{$col} = $value;
1494 # Remove the specified alias from the specified query hash. A copy is made so
1495 # the original query is not modified.
1498 my ($self, $query, $alias) = @_;
1500 my %orig = %{ $query || {} };
1503 foreach my $key (keys %orig) {
1505 $unaliased{$key} = $orig{$key};
1508 $unaliased{$1} = $orig{$key}
1509 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
1519 =item Arguments: \%vals, \%attrs?
1521 =item Return Value: $object
1525 Find an existing record from this resultset. If none exists, instantiate a new
1526 result object and return it. The object will not be saved into your storage
1527 until you call L<DBIx::Class::Row/insert> on it.
1529 If you want objects to be saved immediately, use L</find_or_create> instead.
1535 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1536 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1537 my $exists = $self->find($hash, $attrs);
1538 return defined $exists ? $exists : $self->new_result($hash);
1545 =item Arguments: \%vals
1547 =item Return Value: $object
1551 Inserts a record into the resultset and returns the object representing it.
1553 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
1558 my ($self, $attrs) = @_;
1559 $self->throw_exception( "create needs a hashref" )
1560 unless ref $attrs eq 'HASH';
1561 return $self->new_result($attrs)->insert;
1564 =head2 find_or_create
1568 =item Arguments: \%vals, \%attrs?
1570 =item Return Value: $object
1574 $class->find_or_create({ key => $val, ... });
1576 Tries to find a record based on its primary key or unique constraint; if none
1577 is found, creates one and returns that instead.
1579 my $cd = $schema->resultset('CD')->find_or_create({
1581 artist => 'Massive Attack',
1582 title => 'Mezzanine',
1586 Also takes an optional C<key> attribute, to search by a specific key or unique
1587 constraint. For example:
1589 my $cd = $schema->resultset('CD')->find_or_create(
1591 artist => 'Massive Attack',
1592 title => 'Mezzanine',
1594 { key => 'cd_artist_title' }
1597 See also L</find> and L</update_or_create>. For information on how to declare
1598 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1602 sub find_or_create {
1604 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1605 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1606 my $exists = $self->find($hash, $attrs);
1607 return defined $exists ? $exists : $self->create($hash);
1610 =head2 update_or_create
1614 =item Arguments: \%col_values, { key => $unique_constraint }?
1616 =item Return Value: $object
1620 $class->update_or_create({ col => $val, ... });
1622 First, searches for an existing row matching one of the unique constraints
1623 (including the primary key) on the source of this resultset. If a row is
1624 found, updates it with the other given column values. Otherwise, creates a new
1627 Takes an optional C<key> attribute to search on a specific unique constraint.
1630 # In your application
1631 my $cd = $schema->resultset('CD')->update_or_create(
1633 artist => 'Massive Attack',
1634 title => 'Mezzanine',
1637 { key => 'cd_artist_title' }
1640 If no C<key> is specified, it searches on all unique constraints defined on the
1641 source, including the primary key.
1643 If the C<key> is specified as C<primary>, it searches only on the primary key.
1645 See also L</find> and L</find_or_create>. For information on how to declare
1646 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1650 sub update_or_create {
1652 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1653 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
1655 my $row = $self->find($cond, $attrs);
1657 $row->update($cond);
1661 return $self->create($cond);
1668 =item Arguments: none
1670 =item Return Value: \@cache_objects?
1674 Gets the contents of the cache for the resultset, if the cache is set.
1686 =item Arguments: \@cache_objects
1688 =item Return Value: \@cache_objects
1692 Sets the contents of the cache for the resultset. Expects an arrayref
1693 of objects of the same class as those produced by the resultset. Note that
1694 if the cache is set the resultset will return the cached objects rather
1695 than re-querying the database even if the cache attr is not set.
1700 my ( $self, $data ) = @_;
1701 $self->throw_exception("set_cache requires an arrayref")
1702 if defined($data) && (ref $data ne 'ARRAY');
1703 $self->{all_cache} = $data;
1710 =item Arguments: none
1712 =item Return Value: []
1716 Clears the cache for the resultset.
1721 shift->set_cache(undef);
1724 =head2 related_resultset
1728 =item Arguments: $relationship_name
1730 =item Return Value: $resultset
1734 Returns a related resultset for the supplied relationship name.
1736 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
1740 sub related_resultset {
1741 my ($self, $rel) = @_;
1743 $self->{related_resultsets} ||= {};
1744 return $self->{related_resultsets}{$rel} ||= do {
1745 my $rel_obj = $self->result_source->relationship_info($rel);
1747 $self->throw_exception(
1748 "search_related: result source '" . $self->_source_handle->source_moniker .
1749 "' has no such relationship $rel")
1752 my ($from,$seen) = $self->_resolve_from($rel);
1754 my $join_count = $seen->{$rel};
1755 my $alias = ($join_count > 1 ? join('_', $rel, $join_count) : $rel);
1757 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
1758 my %attrs = %{$self->{attrs}||{}};
1759 delete $attrs{result_class};
1763 if (my $cache = $self->get_cache) {
1764 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
1765 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
1770 my $new = $self->_source_handle
1772 ->resultset($rel_obj->{class})
1781 where => $self->{cond},
1785 $new->set_cache($new_cache) if $new_cache;
1791 my ($self, $extra_join) = @_;
1792 my $source = $self->result_source;
1793 my $attrs = $self->{attrs};
1795 my $from = $attrs->{from}
1796 || [ { $attrs->{alias} => $source->from } ];
1798 my $seen = { %{$attrs->{seen_join}||{}} };
1800 my $join = ($attrs->{join}
1801 ? [ $attrs->{join}, $extra_join ]
1804 # we need to take the prefetch the attrs into account before we
1805 # ->resolve_join as otherwise they get lost - captainL
1806 my $merged = $self->_merge_attr( $join, $attrs->{prefetch} );
1810 ($join ? $source->resolve_join($merged, $attrs->{alias}, $seen) : ()),
1813 return ($from,$seen);
1816 sub _resolved_attrs {
1818 return $self->{_attrs} if $self->{_attrs};
1820 my $attrs = { %{$self->{attrs}||{}} };
1821 my $source = $self->result_source;
1822 my $alias = $attrs->{alias};
1824 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
1825 if ($attrs->{columns}) {
1826 delete $attrs->{as};
1827 } elsif (!$attrs->{select}) {
1828 $attrs->{columns} = [ $source->columns ];
1833 ? (ref $attrs->{select} eq 'ARRAY'
1834 ? [ @{$attrs->{select}} ]
1835 : [ $attrs->{select} ])
1836 : [ map { m/\./ ? $_ : "${alias}.$_" } @{delete $attrs->{columns}} ]
1840 ? (ref $attrs->{as} eq 'ARRAY'
1841 ? [ @{$attrs->{as}} ]
1843 : [ map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{$attrs->{select}} ]
1847 if ($adds = delete $attrs->{include_columns}) {
1848 $adds = [$adds] unless ref $adds eq 'ARRAY';
1849 push(@{$attrs->{select}}, @$adds);
1850 push(@{$attrs->{as}}, map { m/([^.]+)$/; $1 } @$adds);
1852 if ($adds = delete $attrs->{'+select'}) {
1853 $adds = [$adds] unless ref $adds eq 'ARRAY';
1854 push(@{$attrs->{select}},
1855 map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds);
1857 if (my $adds = delete $attrs->{'+as'}) {
1858 $adds = [$adds] unless ref $adds eq 'ARRAY';
1859 push(@{$attrs->{as}}, @$adds);
1862 $attrs->{from} ||= [ { 'me' => $source->from } ];
1864 if (exists $attrs->{join} || exists $attrs->{prefetch}) {
1865 my $join = delete $attrs->{join} || {};
1867 if (defined $attrs->{prefetch}) {
1868 $join = $self->_merge_attr(
1869 $join, $attrs->{prefetch}
1874 $attrs->{from} = # have to copy here to avoid corrupting the original
1877 $source->resolve_join($join, $alias, { %{$attrs->{seen_join}||{}} })
1882 $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct};
1883 if ($attrs->{order_by}) {
1884 $attrs->{order_by} = (ref($attrs->{order_by}) eq 'ARRAY'
1885 ? [ @{$attrs->{order_by}} ]
1886 : [ $attrs->{order_by} ]);
1888 $attrs->{order_by} = [];
1891 my $collapse = $attrs->{collapse} || {};
1892 if (my $prefetch = delete $attrs->{prefetch}) {
1893 $prefetch = $self->_merge_attr({}, $prefetch);
1895 my $seen = $attrs->{seen_join} || {};
1896 foreach my $p (ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch)) {
1897 # bring joins back to level of current class
1898 my @prefetch = $source->resolve_prefetch(
1899 $p, $alias, $seen, \@pre_order, $collapse
1901 push(@{$attrs->{select}}, map { $_->[0] } @prefetch);
1902 push(@{$attrs->{as}}, map { $_->[1] } @prefetch);
1904 push(@{$attrs->{order_by}}, @pre_order);
1906 $attrs->{collapse} = $collapse;
1908 if ($attrs->{page}) {
1909 $attrs->{offset} ||= 0;
1910 $attrs->{offset} += ($attrs->{rows} * ($attrs->{page} - 1));
1913 return $self->{_attrs} = $attrs;
1917 my ($self, $attr) = @_;
1919 if (ref $attr eq 'HASH') {
1920 return $self->_rollout_hash($attr);
1921 } elsif (ref $attr eq 'ARRAY') {
1922 return $self->_rollout_array($attr);
1928 sub _rollout_array {
1929 my ($self, $attr) = @_;
1932 foreach my $element (@{$attr}) {
1933 if (ref $element eq 'HASH') {
1934 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
1935 } elsif (ref $element eq 'ARRAY') {
1936 # XXX - should probably recurse here
1937 push( @rolled_array, @{$self->_rollout_array($element)} );
1939 push( @rolled_array, $element );
1942 return \@rolled_array;
1946 my ($self, $attr) = @_;
1949 foreach my $key (keys %{$attr}) {
1950 push( @rolled_array, { $key => $attr->{$key} } );
1952 return \@rolled_array;
1955 sub _calculate_score {
1956 my ($self, $a, $b) = @_;
1958 if (ref $b eq 'HASH') {
1959 my ($b_key) = keys %{$b};
1960 if (ref $a eq 'HASH') {
1961 my ($a_key) = keys %{$a};
1962 if ($a_key eq $b_key) {
1963 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
1968 return ($a eq $b_key) ? 1 : 0;
1971 if (ref $a eq 'HASH') {
1972 my ($a_key) = keys %{$a};
1973 return ($b eq $a_key) ? 1 : 0;
1975 return ($b eq $a) ? 1 : 0;
1981 my ($self, $a, $b) = @_;
1983 return $b unless defined($a);
1984 return $a unless defined($b);
1986 $a = $self->_rollout_attr($a);
1987 $b = $self->_rollout_attr($b);
1990 foreach my $b_element ( @{$b} ) {
1991 # find best candidate from $a to merge $b_element into
1992 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
1993 foreach my $a_element ( @{$a} ) {
1994 my $score = $self->_calculate_score( $a_element, $b_element );
1995 if ($score > $best_candidate->{score}) {
1996 $best_candidate->{position} = $position;
1997 $best_candidate->{score} = $score;
2001 my ($b_key) = ( ref $b_element eq 'HASH' ) ? keys %{$b_element} : ($b_element);
2002 if ($best_candidate->{score} == 0 || exists $seen_keys->{$b_key}) {
2003 push( @{$a}, $b_element );
2005 $seen_keys->{$b_key} = 1; # don't merge the same key twice
2006 my $a_best = $a->[$best_candidate->{position}];
2007 # merge a_best and b_element together and replace original with merged
2008 if (ref $a_best ne 'HASH') {
2009 $a->[$best_candidate->{position}] = $b_element;
2010 } elsif (ref $b_element eq 'HASH') {
2011 my ($key) = keys %{$a_best};
2012 $a->[$best_candidate->{position}] = { $key => $self->_merge_attr($a_best->{$key}, $b_element->{$key}) };
2024 $self->_source_handle($_[0]->handle);
2026 $self->_source_handle->resolve;
2030 =head2 throw_exception
2032 See L<DBIx::Class::Schema/throw_exception> for details.
2036 sub throw_exception {
2038 $self->_source_handle->schema->throw_exception(@_);
2041 # XXX: FIXME: Attributes docs need clearing up
2045 The resultset takes various attributes that modify its behavior. Here's an
2052 =item Value: ($order_by | \@order_by)
2056 Which column(s) to order the results by. This is currently passed
2057 through directly to SQL, so you can give e.g. C<year DESC> for a
2058 descending order on the column `year'.
2060 Please note that if you have C<quote_char> enabled (see
2061 L<DBIx::Class::Storage::DBI/connect_info>) you will need to do C<\'year DESC' > to
2062 specify an order. (The scalar ref causes it to be passed as raw sql to the DB,
2063 so you will need to manually quote things as appropriate.)
2069 =item Value: \@columns
2073 Shortcut to request a particular set of columns to be retrieved. Adds
2074 C<me.> onto the start of any column without a C<.> in it and sets C<select>
2075 from that, then auto-populates C<as> from C<select> as normal. (You may also
2076 use the C<cols> attribute, as in earlier versions of DBIC.)
2078 =head2 include_columns
2082 =item Value: \@columns
2086 Shortcut to include additional columns in the returned results - for example
2088 $schema->resultset('CD')->search(undef, {
2089 include_columns => ['artist.name'],
2093 would return all CDs and include a 'name' column to the information
2094 passed to object inflation. Note that the 'artist' is the name of the
2095 column (or relationship) accessor, and 'name' is the name of the column
2096 accessor in the related table.
2102 =item Value: \@select_columns
2106 Indicates which columns should be selected from the storage. You can use
2107 column names, or in the case of RDBMS back ends, function or stored procedure
2110 $rs = $schema->resultset('Employee')->search(undef, {
2113 { count => 'employeeid' },
2118 When you use function/stored procedure names and do not supply an C<as>
2119 attribute, the column names returned are storage-dependent. E.g. MySQL would
2120 return a column named C<count(employeeid)> in the above example.
2126 Indicates additional columns to be selected from storage. Works the same as
2127 L<select> but adds columns to the selection.
2135 Indicates additional column names for those added via L<+select>.
2143 =item Value: \@inflation_names
2147 Indicates column names for object inflation. That is, c< as >
2148 indicates the name that the column can be accessed as via the
2149 C<get_column> method (or via the object accessor, B<if one already
2150 exists>). It has nothing to do with the SQL code C< SELECT foo AS bar
2153 The C< as > attribute is used in conjunction with C<select>,
2154 usually when C<select> contains one or more function or stored
2157 $rs = $schema->resultset('Employee')->search(undef, {
2160 { count => 'employeeid' }
2162 as => ['name', 'employee_count'],
2165 my $employee = $rs->first(); # get the first Employee
2167 If the object against which the search is performed already has an accessor
2168 matching a column name specified in C<as>, the value can be retrieved using
2169 the accessor as normal:
2171 my $name = $employee->name();
2173 If on the other hand an accessor does not exist in the object, you need to
2174 use C<get_column> instead:
2176 my $employee_count = $employee->get_column('employee_count');
2178 You can create your own accessors if required - see
2179 L<DBIx::Class::Manual::Cookbook> for details.
2181 Please note: This will NOT insert an C<AS employee_count> into the SQL
2182 statement produced, it is used for internal access only. Thus
2183 attempting to use the accessor in an C<order_by> clause or similar
2184 will fail miserably.
2186 To get around this limitation, you can supply literal SQL to your
2187 C<select> attibute that contains the C<AS alias> text, eg:
2189 select => [\'myfield AS alias']
2195 =item Value: ($rel_name | \@rel_names | \%rel_names)
2199 Contains a list of relationships that should be joined for this query. For
2202 # Get CDs by Nine Inch Nails
2203 my $rs = $schema->resultset('CD')->search(
2204 { 'artist.name' => 'Nine Inch Nails' },
2205 { join => 'artist' }
2208 Can also contain a hash reference to refer to the other relation's relations.
2211 package MyApp::Schema::Track;
2212 use base qw/DBIx::Class/;
2213 __PACKAGE__->table('track');
2214 __PACKAGE__->add_columns(qw/trackid cd position title/);
2215 __PACKAGE__->set_primary_key('trackid');
2216 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
2219 # In your application
2220 my $rs = $schema->resultset('Artist')->search(
2221 { 'track.title' => 'Teardrop' },
2223 join => { cd => 'track' },
2224 order_by => 'artist.name',
2228 You need to use the relationship (not the table) name in conditions,
2229 because they are aliased as such. The current table is aliased as "me", so
2230 you need to use me.column_name in order to avoid ambiguity. For example:
2232 # Get CDs from 1984 with a 'Foo' track
2233 my $rs = $schema->resultset('CD')->search(
2236 'tracks.name' => 'Foo'
2238 { join => 'tracks' }
2241 If the same join is supplied twice, it will be aliased to <rel>_2 (and
2242 similarly for a third time). For e.g.
2244 my $rs = $schema->resultset('Artist')->search({
2245 'cds.title' => 'Down to Earth',
2246 'cds_2.title' => 'Popular',
2248 join => [ qw/cds cds/ ],
2251 will return a set of all artists that have both a cd with title 'Down
2252 to Earth' and a cd with title 'Popular'.
2254 If you want to fetch related objects from other tables as well, see C<prefetch>
2261 =item Value: ($rel_name | \@rel_names | \%rel_names)
2265 Contains one or more relationships that should be fetched along with the main
2266 query (when they are accessed afterwards they will have already been
2267 "prefetched"). This is useful for when you know you will need the related
2268 objects, because it saves at least one query:
2270 my $rs = $schema->resultset('Tag')->search(
2279 The initial search results in SQL like the following:
2281 SELECT tag.*, cd.*, artist.* FROM tag
2282 JOIN cd ON tag.cd = cd.cdid
2283 JOIN artist ON cd.artist = artist.artistid
2285 L<DBIx::Class> has no need to go back to the database when we access the
2286 C<cd> or C<artist> relationships, which saves us two SQL statements in this
2289 Simple prefetches will be joined automatically, so there is no need
2290 for a C<join> attribute in the above search. If you're prefetching to
2291 depth (e.g. { cd => { artist => 'label' } or similar), you'll need to
2292 specify the join as well.
2294 C<prefetch> can be used with the following relationship types: C<belongs_to>,
2295 C<has_one> (or if you're using C<add_relationship>, any relationship declared
2296 with an accessor type of 'single' or 'filter').
2306 Makes the resultset paged and specifies the page to retrieve. Effectively
2307 identical to creating a non-pages resultset and then calling ->page($page)
2310 If L<rows> attribute is not specified it defualts to 10 rows per page.
2320 Specifes the maximum number of rows for direct retrieval or the number of
2321 rows per page if the page attribute or method is used.
2327 =item Value: $offset
2331 Specifies the (zero-based) row number for the first row to be returned, or the
2332 of the first row of the first page if paging is used.
2338 =item Value: \@columns
2342 A arrayref of columns to group by. Can include columns of joined tables.
2344 group_by => [qw/ column1 column2 ... /]
2350 =item Value: $condition
2354 HAVING is a select statement attribute that is applied between GROUP BY and
2355 ORDER BY. It is applied to the after the grouping calculations have been
2358 having => { 'count(employee)' => { '>=', 100 } }
2364 =item Value: (0 | 1)
2368 Set to 1 to group by all columns.
2374 Adds to the WHERE clause.
2376 # only return rows WHERE deleted IS NULL for all searches
2377 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
2379 Can be overridden by passing C<{ where => undef }> as an attribute
2386 Set to 1 to cache search results. This prevents extra SQL queries if you
2387 revisit rows in your ResultSet:
2389 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
2391 while( my $artist = $resultset->next ) {
2395 $rs->first; # without cache, this would issue a query
2397 By default, searches are not cached.
2399 For more examples of using these attributes, see
2400 L<DBIx::Class::Manual::Cookbook>.
2406 =item Value: \@from_clause
2410 The C<from> attribute gives you manual control over the C<FROM> clause of SQL
2411 statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
2414 NOTE: Use this on your own risk. This allows you to shoot off your foot!
2416 C<join> will usually do what you need and it is strongly recommended that you
2417 avoid using C<from> unless you cannot achieve the desired result using C<join>.
2418 And we really do mean "cannot", not just tried and failed. Attempting to use
2419 this because you're having problems with C<join> is like trying to use x86
2420 ASM because you've got a syntax error in your C. Trust us on this.
2422 Now, if you're still really, really sure you need to use this (and if you're
2423 not 100% sure, ask the mailing list first), here's an explanation of how this
2426 The syntax is as follows -
2429 { <alias1> => <table1> },
2431 { <alias2> => <table2>, -join_type => 'inner|left|right' },
2432 [], # nested JOIN (optional)
2433 { <table1.column1> => <table2.column2>, ... (more conditions) },
2435 # More of the above [ ] may follow for additional joins
2442 ON <table1.column1> = <table2.column2>
2443 <more joins may follow>
2445 An easy way to follow the examples below is to remember the following:
2447 Anything inside "[]" is a JOIN
2448 Anything inside "{}" is a condition for the enclosing JOIN
2450 The following examples utilize a "person" table in a family tree application.
2451 In order to express parent->child relationships, this table is self-joined:
2453 # Person->belongs_to('father' => 'Person');
2454 # Person->belongs_to('mother' => 'Person');
2456 C<from> can be used to nest joins. Here we return all children with a father,
2457 then search against all mothers of those children:
2459 $rs = $schema->resultset('Person')->search(
2462 alias => 'mother', # alias columns in accordance with "from"
2464 { mother => 'person' },
2467 { child => 'person' },
2469 { father => 'person' },
2470 { 'father.person_id' => 'child.father_id' }
2473 { 'mother.person_id' => 'child.mother_id' }
2480 # SELECT mother.* FROM person mother
2483 # JOIN person father
2484 # ON ( father.person_id = child.father_id )
2486 # ON ( mother.person_id = child.mother_id )
2488 The type of any join can be controlled manually. To search against only people
2489 with a father in the person table, we could explicitly use C<INNER JOIN>:
2491 $rs = $schema->resultset('Person')->search(
2494 alias => 'child', # alias columns in accordance with "from"
2496 { child => 'person' },
2498 { father => 'person', -join_type => 'inner' },
2499 { 'father.id' => 'child.father_id' }
2506 # SELECT child.* FROM person child
2507 # INNER JOIN person father ON child.father_id = father.id