1 package DBIx::Class::ResultSet;
9 use Carp::Clan qw/^DBIx::Class/;
12 use DBIx::Class::ResultSetColumn;
13 use DBIx::Class::ResultSourceHandle;
16 use base qw/DBIx::Class/;
18 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class _source_handle/);
22 DBIx::Class::ResultSet - Responsible for fetching and creating resultset.
26 my $rs = $schema->resultset('User')->search({ registered => 1 });
27 my @rows = $schema->resultset('CD')->search({ year => 2005 })->all();
31 The resultset is also known as an iterator. It is responsible for handling
32 queries that may return an arbitrary number of rows, e.g. via L</search>
33 or a C<has_many> relationship.
35 In the examples below, the following table classes are used:
37 package MyApp::Schema::Artist;
38 use base qw/DBIx::Class/;
39 __PACKAGE__->load_components(qw/Core/);
40 __PACKAGE__->table('artist');
41 __PACKAGE__->add_columns(qw/artistid name/);
42 __PACKAGE__->set_primary_key('artistid');
43 __PACKAGE__->has_many(cds => 'MyApp::Schema::CD');
46 package MyApp::Schema::CD;
47 use base qw/DBIx::Class/;
48 __PACKAGE__->load_components(qw/Core/);
49 __PACKAGE__->table('cd');
50 __PACKAGE__->add_columns(qw/cdid artist title year/);
51 __PACKAGE__->set_primary_key('cdid');
52 __PACKAGE__->belongs_to(artist => 'MyApp::Schema::Artist');
57 If a resultset is used in a numeric context it returns the L</count>.
58 However, if it is used in a booleand context it is always true. So if
59 you want to check if a resultset has any results use C<if $rs != 0>.
60 C<if $rs> will always be true.
68 =item Arguments: $source, \%$attrs
70 =item Return Value: $rs
74 The resultset constructor. Takes a source object (usually a
75 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
76 L</ATTRIBUTES> below). Does not perform any queries -- these are
77 executed as needed by the other methods.
79 Generally you won't need to construct a resultset manually. You'll
80 automatically get one from e.g. a L</search> called in scalar context:
82 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
84 IMPORTANT: If called on an object, proxies to new_result instead so
86 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
88 will return a CD object, not a ResultSet.
94 return $class->new_result(@_) if ref $class;
96 my ($source, $attrs) = @_;
97 $source = $source->handle
98 unless $source->isa('DBIx::Class::ResultSourceHandle');
99 $attrs = { %{$attrs||{}} };
101 if ($attrs->{page}) {
102 $attrs->{rows} ||= 10;
105 $attrs->{alias} ||= 'me';
107 # Creation of {} and bless separated to mitigate RH perl bug
108 # see https://bugzilla.redhat.com/show_bug.cgi?id=196836
110 _source_handle => $source,
111 cond => $attrs->{where},
120 $attrs->{result_class} || $source->resolve->result_class
130 =item Arguments: $cond, \%attrs?
132 =item Return Value: $resultset (scalar context), @row_objs (list context)
136 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
137 my $new_rs = $cd_rs->search({ year => 2005 });
139 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
140 # year = 2005 OR year = 2004
142 If you need to pass in additional attributes but no additional condition,
143 call it as C<search(undef, \%attrs)>.
145 # "SELECT name, artistid FROM $artist_table"
146 my @all_artists = $schema->resultset('Artist')->search(undef, {
147 columns => [qw/name artistid/],
150 For a list of attributes that can be passed to C<search>, see
151 L</ATTRIBUTES>. For more examples of using this function, see
152 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
153 documentation for the first argument, see L<SQL::Abstract>.
155 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
161 my $rs = $self->search_rs( @_ );
162 return (wantarray ? $rs->all : $rs);
169 =item Arguments: $cond, \%attrs?
171 =item Return Value: $resultset
175 This method does the same exact thing as search() except it will
176 always return a resultset, even in list context.
184 $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
185 my $our_attrs = { %{$self->{attrs}} };
186 my $having = delete $our_attrs->{having};
187 my $where = delete $our_attrs->{where};
191 my %safe = (alias => 1, cache => 1);
194 (@_ && defined($_[0])) # @_ == () or (undef)
196 (keys %$attrs # empty attrs or only 'safe' attrs
197 && List::Util::first { !$safe{$_} } keys %$attrs)
199 # no search, effectively just a clone
200 $rows = $self->get_cache;
203 my $new_attrs = { %{$our_attrs}, %{$attrs} };
205 # merge new attrs into inherited
206 foreach my $key (qw/join prefetch +select +as/) {
207 next unless exists $attrs->{$key};
208 $new_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key});
213 (@_ == 1 || ref $_[0] eq "HASH")
215 (ref $_[0] eq 'HASH')
217 (keys %{ $_[0] } > 0)
225 ? $self->throw_exception("Odd number of arguments to search")
232 if (defined $where) {
233 $new_attrs->{where} = (
234 defined $new_attrs->{where}
237 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
238 } $where, $new_attrs->{where}
245 $new_attrs->{where} = (
246 defined $new_attrs->{where}
249 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
250 } $cond, $new_attrs->{where}
256 if (defined $having) {
257 $new_attrs->{having} = (
258 defined $new_attrs->{having}
261 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
262 } $having, $new_attrs->{having}
268 my $rs = (ref $self)->new($self->result_source, $new_attrs);
270 $rs->set_cache($rows);
275 =head2 search_literal
279 =item Arguments: $sql_fragment, @bind_values
281 =item Return Value: $resultset (scalar context), @row_objs (list context)
285 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
286 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
288 Pass a literal chunk of SQL to be added to the conditional part of the
291 CAVEAT: C<search_literal> is provided for Class::DBI compatibility and should
292 only be used in that context. There are known problems using C<search_literal>
293 in chained queries; it can result in bind values in the wrong order. See
294 L<DBIx::Class::Manual::Cookbook/Searching> and
295 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
296 require C<search_literal>.
301 my ($self, $cond, @vals) = @_;
302 my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {});
303 $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ];
304 return $self->search(\$cond, $attrs);
311 =item Arguments: @values | \%cols, \%attrs?
313 =item Return Value: $row_object | undef
317 Finds a row based on its primary key or unique constraint. For example, to find
318 a row by its primary key:
320 my $cd = $schema->resultset('CD')->find(5);
322 You can also find a row by a specific unique constraint using the C<key>
323 attribute. For example:
325 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
326 key => 'cd_artist_title'
329 Additionally, you can specify the columns explicitly by name:
331 my $cd = $schema->resultset('CD')->find(
333 artist => 'Massive Attack',
334 title => 'Mezzanine',
336 { key => 'cd_artist_title' }
339 If the C<key> is specified as C<primary>, it searches only on the primary key.
341 If no C<key> is specified, it searches on all unique constraints defined on the
342 source for which column data is provided, including the primary key.
344 If your table does not have a primary key, you B<must> provide a value for the
345 C<key> attribute matching one of the unique constraints on the source.
347 In addition to C<key>, L</find> recognizes and applies standard
348 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
350 Note: If your query does not return only one row, a warning is generated:
352 Query returned more than one row
354 See also L</find_or_create> and L</update_or_create>. For information on how to
355 declare unique constraints, see
356 L<DBIx::Class::ResultSource/add_unique_constraint>.
362 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
364 # Default to the primary key, but allow a specific key
365 my @cols = exists $attrs->{key}
366 ? $self->result_source->unique_constraint_columns($attrs->{key})
367 : $self->result_source->primary_columns;
368 $self->throw_exception(
369 "Can't find unless a primary key is defined or unique constraint is specified"
372 # Parse out a hashref from input
374 if (ref $_[0] eq 'HASH') {
375 $input_query = { %{$_[0]} };
377 elsif (@_ == @cols) {
379 @{$input_query}{@cols} = @_;
382 # Compatibility: Allow e.g. find(id => $value)
383 carp "Find by key => value deprecated; please use a hashref instead";
387 my (%related, $info);
389 KEY: foreach my $key (keys %$input_query) {
390 if (ref($input_query->{$key})
391 && ($info = $self->result_source->relationship_info($key))) {
392 my $val = delete $input_query->{$key};
393 next KEY if (ref($val) eq 'ARRAY'); # has_many for multi_create
394 my $rel_q = $self->result_source->resolve_condition(
395 $info->{cond}, $val, $key
397 die "Can't handle OR join condition in find" if ref($rel_q) eq 'ARRAY';
398 @related{keys %$rel_q} = values %$rel_q;
401 if (my @keys = keys %related) {
402 @{$input_query}{@keys} = values %related;
406 # Build the final query: Default to the disjunction of the unique queries,
407 # but allow the input query in case the ResultSet defines the query or the
408 # user is abusing find
409 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
411 if (exists $attrs->{key}) {
412 my @unique_cols = $self->result_source->unique_constraint_columns($attrs->{key});
413 my $unique_query = $self->_build_unique_query($input_query, \@unique_cols);
414 $query = $self->_add_alias($unique_query, $alias);
417 my @unique_queries = $self->_unique_queries($input_query, $attrs);
418 $query = @unique_queries
419 ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
420 : $self->_add_alias($input_query, $alias);
425 my $rs = $self->search($query, $attrs);
426 if (keys %{$rs->_resolved_attrs->{collapse}}) {
428 carp "Query returned more than one row" if $rs->next;
436 if (keys %{$self->_resolved_attrs->{collapse}}) {
437 my $rs = $self->search($query);
439 carp "Query returned more than one row" if $rs->next;
443 return $self->single($query);
450 # Add the specified alias to the specified query hash. A copy is made so the
451 # original query is not modified.
454 my ($self, $query, $alias) = @_;
456 my %aliased = %$query;
457 foreach my $col (grep { ! m/\./ } keys %aliased) {
458 $aliased{"$alias.$col"} = delete $aliased{$col};
466 # Build a list of queries which satisfy unique constraints.
468 sub _unique_queries {
469 my ($self, $query, $attrs) = @_;
471 my @constraint_names = exists $attrs->{key}
473 : $self->result_source->unique_constraint_names;
475 my $where = $self->_collapse_cond($self->{attrs}{where} || {});
476 my $num_where = scalar keys %$where;
479 foreach my $name (@constraint_names) {
480 my @unique_cols = $self->result_source->unique_constraint_columns($name);
481 my $unique_query = $self->_build_unique_query($query, \@unique_cols);
483 my $num_cols = scalar @unique_cols;
484 my $num_query = scalar keys %$unique_query;
486 my $total = $num_query + $num_where;
487 if ($num_query && ($num_query == $num_cols || $total == $num_cols)) {
488 # The query is either unique on its own or is unique in combination with
489 # the existing where clause
490 push @unique_queries, $unique_query;
494 return @unique_queries;
497 # _build_unique_query
499 # Constrain the specified query hash based on the specified column names.
501 sub _build_unique_query {
502 my ($self, $query, $unique_cols) = @_;
505 map { $_ => $query->{$_} }
506 grep { exists $query->{$_} }
511 =head2 search_related
515 =item Arguments: $rel, $cond, \%attrs?
517 =item Return Value: $new_resultset
521 $new_rs = $cd_rs->search_related('artist', {
525 Searches the specified relationship, optionally specifying a condition and
526 attributes for matching records. See L</ATTRIBUTES> for more information.
531 return shift->related_resultset(shift)->search(@_);
534 =head2 search_related_rs
536 This method works exactly the same as search_related, except that
537 it guarantees a restultset, even in list context.
541 sub search_related_rs {
542 return shift->related_resultset(shift)->search_rs(@_);
549 =item Arguments: none
551 =item Return Value: $cursor
555 Returns a storage-driven cursor to the given resultset. See
556 L<DBIx::Class::Cursor> for more information.
563 my $attrs = { %{$self->_resolved_attrs} };
564 return $self->{cursor}
565 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
566 $attrs->{where},$attrs);
573 =item Arguments: $cond?
575 =item Return Value: $row_object?
579 my $cd = $schema->resultset('CD')->single({ year => 2001 });
581 Inflates the first result without creating a cursor if the resultset has
582 any records in it; if not returns nothing. Used by L</find> as a lean version of
585 While this method can take an optional search condition (just like L</search>)
586 being a fast-code-path it does not recognize search attributes. If you need to
587 add extra joins or similar, call L</search> and then chain-call L</single> on the
588 L<DBIx::Class::ResultSet> returned.
594 As of 0.08100, this method enforces the assumption that the preceeding
595 query returns only one row. If more than one row is returned, you will receive
598 Query returned more than one row
600 In this case, you should be using L</first> or L</find> instead, or if you really
601 know what you are doing, use the L</rows> attribute to explicitly limit the size
609 my ($self, $where) = @_;
611 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
614 my $attrs = { %{$self->_resolved_attrs} };
616 if (defined $attrs->{where}) {
619 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
620 $where, delete $attrs->{where} ]
623 $attrs->{where} = $where;
627 # XXX: Disabled since it doesn't infer uniqueness in all cases
628 # unless ($self->_is_unique_query($attrs->{where})) {
629 # carp "Query not guaranteed to return a single row"
630 # . "; please declare your unique constraints or use search instead";
633 my @data = $self->result_source->storage->select_single(
634 $attrs->{from}, $attrs->{select},
635 $attrs->{where}, $attrs
638 return (@data ? ($self->_construct_object(@data))[0] : undef);
643 # Try to determine if the specified query is guaranteed to be unique, based on
644 # the declared unique constraints.
646 sub _is_unique_query {
647 my ($self, $query) = @_;
649 my $collapsed = $self->_collapse_query($query);
650 my $alias = $self->{attrs}{alias};
652 foreach my $name ($self->result_source->unique_constraint_names) {
653 my @unique_cols = map {
655 } $self->result_source->unique_constraint_columns($name);
657 # Count the values for each unique column
658 my %seen = map { $_ => 0 } @unique_cols;
660 foreach my $key (keys %$collapsed) {
661 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
662 next unless exists $seen{$aliased}; # Additional constraints are okay
663 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
666 # If we get 0 or more than 1 value for a column, it's not necessarily unique
667 return 1 unless grep { $_ != 1 } values %seen;
675 # Recursively collapse the query, accumulating values for each column.
677 sub _collapse_query {
678 my ($self, $query, $collapsed) = @_;
682 if (ref $query eq 'ARRAY') {
683 foreach my $subquery (@$query) {
684 next unless ref $subquery; # -or
685 # warn "ARRAY: " . Dumper $subquery;
686 $collapsed = $self->_collapse_query($subquery, $collapsed);
689 elsif (ref $query eq 'HASH') {
690 if (keys %$query and (keys %$query)[0] eq '-and') {
691 foreach my $subquery (@{$query->{-and}}) {
692 # warn "HASH: " . Dumper $subquery;
693 $collapsed = $self->_collapse_query($subquery, $collapsed);
697 # warn "LEAF: " . Dumper $query;
698 foreach my $col (keys %$query) {
699 my $value = $query->{$col};
700 $collapsed->{$col}{$value}++;
712 =item Arguments: $cond?
714 =item Return Value: $resultsetcolumn
718 my $max_length = $rs->get_column('length')->max;
720 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
725 my ($self, $column) = @_;
726 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
734 =item Arguments: $cond, \%attrs?
736 =item Return Value: $resultset (scalar context), @row_objs (list context)
740 # WHERE title LIKE '%blue%'
741 $cd_rs = $rs->search_like({ title => '%blue%'});
743 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
744 that this is simply a convenience method retained for ex Class::DBI users.
745 You most likely want to use L</search> with specific operators.
747 For more information, see L<DBIx::Class::Manual::Cookbook>.
753 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
754 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
755 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
756 return $class->search($query, { %$attrs });
763 =item Arguments: $first, $last
765 =item Return Value: $resultset (scalar context), @row_objs (list context)
769 Returns a resultset or object list representing a subset of elements from the
770 resultset slice is called on. Indexes are from 0, i.e., to get the first
773 my ($one, $two, $three) = $rs->slice(0, 2);
778 my ($self, $min, $max) = @_;
779 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
780 $attrs->{offset} = $self->{attrs}{offset} || 0;
781 $attrs->{offset} += $min;
782 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
783 return $self->search(undef(), $attrs);
784 #my $slice = (ref $self)->new($self->result_source, $attrs);
785 #return (wantarray ? $slice->all : $slice);
792 =item Arguments: none
794 =item Return Value: $result?
798 Returns the next element in the resultset (C<undef> is there is none).
800 Can be used to efficiently iterate over records in the resultset:
802 my $rs = $schema->resultset('CD')->search;
803 while (my $cd = $rs->next) {
807 Note that you need to store the resultset object, and call C<next> on it.
808 Calling C<< resultset('Table')->next >> repeatedly will always return the
809 first record from the resultset.
815 if (my $cache = $self->get_cache) {
816 $self->{all_cache_position} ||= 0;
817 return $cache->[$self->{all_cache_position}++];
819 if ($self->{attrs}{cache}) {
820 $self->{all_cache_position} = 1;
821 return ($self->all)[0];
823 if ($self->{stashed_objects}) {
824 my $obj = shift(@{$self->{stashed_objects}});
825 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
829 exists $self->{stashed_row}
830 ? @{delete $self->{stashed_row}}
831 : $self->cursor->next
833 return undef unless (@row);
834 my ($row, @more) = $self->_construct_object(@row);
835 $self->{stashed_objects} = \@more if @more;
839 sub _construct_object {
840 my ($self, @row) = @_;
841 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row);
842 my @new = $self->result_class->inflate_result($self->result_source, @$info);
843 @new = $self->{_attrs}{record_filter}->(@new)
844 if exists $self->{_attrs}{record_filter};
848 sub _collapse_result {
849 my ($self, $as_proto, $row) = @_;
853 # 'foo' => [ undef, 'foo' ]
854 # 'foo.bar' => [ 'foo', 'bar' ]
855 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
857 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
859 my %collapse = %{$self->{_attrs}{collapse}||{}};
863 # if we're doing collapsing (has_many prefetch) we need to grab records
864 # until the PK changes, so fill @pri_index. if not, we leave it empty so
865 # we know we don't have to bother.
867 # the reason for not using the collapse stuff directly is because if you
868 # had for e.g. two artists in a row with no cds, the collapse info for
869 # both would be NULL (undef) so you'd lose the second artist
871 # store just the index so we can check the array positions from the row
872 # without having to contruct the full hash
874 if (keys %collapse) {
875 my %pri = map { ($_ => 1) } $self->result_source->primary_columns;
876 foreach my $i (0 .. $#construct_as) {
877 next if defined($construct_as[$i][0]); # only self table
878 if (delete $pri{$construct_as[$i][1]}) {
879 push(@pri_index, $i);
881 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
885 # no need to do an if, it'll be empty if @pri_index is empty anyway
887 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
891 do { # no need to check anything at the front, we always want the first row
895 foreach my $this_as (@construct_as) {
896 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
899 push(@const_rows, \%const);
901 } until ( # no pri_index => no collapse => drop straight out
904 do { # get another row, stash it, drop out if different PK
906 @copy = $self->cursor->next;
907 $self->{stashed_row} = \@copy;
909 # last thing in do block, counts as true if anything doesn't match
911 # check xor defined first for NULL vs. NOT NULL then if one is
912 # defined the other must be so check string equality
915 (defined $pri_vals{$_} ^ defined $copy[$_])
916 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
921 my $alias = $self->{attrs}{alias};
928 foreach my $const (@const_rows) {
929 scalar @const_keys or do {
930 @const_keys = sort { length($a) <=> length($b) } keys %$const;
932 foreach my $key (@const_keys) {
935 my @parts = split(/\./, $key);
937 my $data = $const->{$key};
938 foreach my $p (@parts) {
939 $target = $target->[1]->{$p} ||= [];
941 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
942 # collapsing at this point and on final part
943 my $pos = $collapse_pos{$cur};
944 CK: foreach my $ck (@ckey) {
945 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
946 $collapse_pos{$cur} = $data;
947 delete @collapse_pos{ # clear all positioning for sub-entries
948 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
955 if (exists $collapse{$cur}) {
956 $target = $target->[-1];
959 $target->[0] = $data;
961 $info->[0] = $const->{$key};
973 =item Arguments: $result_source?
975 =item Return Value: $result_source
979 An accessor for the primary ResultSource object from which this ResultSet
986 =item Arguments: $result_class?
988 =item Return Value: $result_class
992 An accessor for the class to use when creating row objects. Defaults to
993 C<< result_source->result_class >> - which in most cases is the name of the
994 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
999 my ($self, $result_class) = @_;
1000 if ($result_class) {
1001 $self->ensure_class_loaded($result_class);
1002 $self->_result_class($result_class);
1004 $self->_result_class;
1011 =item Arguments: $cond, \%attrs??
1013 =item Return Value: $count
1017 Performs an SQL C<COUNT> with the same query as the resultset was built
1018 with to find the number of elements. If passed arguments, does a search
1019 on the resultset and counts the results of that.
1021 Note: When using C<count> with C<group_by>, L<DBIx::Class> emulates C<GROUP BY>
1022 using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do
1023 not support C<DISTINCT> with multiple columns. If you are using such a
1024 database, you should only use columns from the main table in your C<group_by>
1031 return $self->search(@_)->count if @_ and defined $_[0];
1032 return scalar @{ $self->get_cache } if $self->get_cache;
1033 my $count = $self->_count;
1034 return 0 unless $count;
1036 # need to take offset from resolved attrs
1038 $count -= $self->{_attrs}{offset} if $self->{_attrs}{offset};
1039 $count = $self->{attrs}{rows} if
1040 $self->{attrs}{rows} and $self->{attrs}{rows} < $count;
1041 $count = 0 if ($count < 0);
1045 sub _count { # Separated out so pager can get the full count
1047 my $select = { count => '*' };
1049 my $attrs = { %{$self->_resolved_attrs} };
1050 if (my $group_by = delete $attrs->{group_by}) {
1051 delete $attrs->{having};
1052 my @distinct = (ref $group_by ? @$group_by : ($group_by));
1053 # todo: try CONCAT for multi-column pk
1054 my @pk = $self->result_source->primary_columns;
1056 my $alias = $attrs->{alias};
1057 foreach my $column (@distinct) {
1058 if ($column =~ qr/^(?:\Q${alias}.\E)?$pk[0]$/) {
1059 @distinct = ($column);
1065 $select = { count => { distinct => \@distinct } };
1068 $attrs->{select} = $select;
1069 $attrs->{as} = [qw/count/];
1071 # offset, order by and page are not needed to count. record_filter is cdbi
1072 delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/;
1074 my $tmp_rs = (ref $self)->new($self->result_source, $attrs);
1075 my ($count) = $tmp_rs->cursor->next;
1083 =head2 count_literal
1087 =item Arguments: $sql_fragment, @bind_values
1089 =item Return Value: $count
1093 Counts the results in a literal query. Equivalent to calling L</search_literal>
1094 with the passed arguments, then L</count>.
1098 sub count_literal { shift->search_literal(@_)->count; }
1104 =item Arguments: none
1106 =item Return Value: @objects
1110 Returns all elements in the resultset. Called implicitly if the resultset
1111 is returned in list context.
1118 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1121 return @{ $self->get_cache } if $self->get_cache;
1125 # TODO: don't call resolve here
1126 if (keys %{$self->_resolved_attrs->{collapse}}) {
1127 # if ($self->{attrs}{prefetch}) {
1128 # Using $self->cursor->all is really just an optimisation.
1129 # If we're collapsing has_many prefetches it probably makes
1130 # very little difference, and this is cleaner than hacking
1131 # _construct_object to survive the approach
1132 my @row = $self->cursor->next;
1134 push(@obj, $self->_construct_object(@row));
1135 @row = (exists $self->{stashed_row}
1136 ? @{delete $self->{stashed_row}}
1137 : $self->cursor->next);
1140 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1143 $self->set_cache(\@obj) if $self->{attrs}{cache};
1151 =item Arguments: none
1153 =item Return Value: $self
1157 Resets the resultset's cursor, so you can iterate through the elements again.
1163 delete $self->{_attrs} if exists $self->{_attrs};
1164 $self->{all_cache_position} = 0;
1165 $self->cursor->reset;
1173 =item Arguments: none
1175 =item Return Value: $object?
1179 Resets the resultset and returns an object for the first result (if the
1180 resultset returns anything).
1185 return $_[0]->reset->next;
1188 # _cond_for_update_delete
1190 # update/delete require the condition to be modified to handle
1191 # the differing SQL syntax available. This transforms the $self->{cond}
1192 # appropriately, returning the new condition.
1194 sub _cond_for_update_delete {
1195 my ($self, $full_cond) = @_;
1198 $full_cond ||= $self->{cond};
1199 # No-op. No condition, we're updating/deleting everything
1200 return $cond unless ref $full_cond;
1202 if (ref $full_cond eq 'ARRAY') {
1206 foreach my $key (keys %{$_}) {
1208 $hash{$1} = $_->{$key};
1214 elsif (ref $full_cond eq 'HASH') {
1215 if ((keys %{$full_cond})[0] eq '-and') {
1218 my @cond = @{$full_cond->{-and}};
1219 for (my $i = 0; $i < @cond; $i++) {
1220 my $entry = $cond[$i];
1223 if (ref $entry eq 'HASH') {
1224 $hash = $self->_cond_for_update_delete($entry);
1227 $entry =~ /([^.]+)$/;
1228 $hash->{$1} = $cond[++$i];
1231 push @{$cond->{-and}}, $hash;
1235 foreach my $key (keys %{$full_cond}) {
1237 $cond->{$1} = $full_cond->{$key};
1242 $self->throw_exception(
1243 "Can't update/delete on resultset with condition unless hash or array"
1255 =item Arguments: \%values
1257 =item Return Value: $storage_rv
1261 Sets the specified columns in the resultset to the supplied values in a
1262 single query. Return value will be true if the update succeeded or false
1263 if no records were updated; exact type of success value is storage-dependent.
1268 my ($self, $values) = @_;
1269 $self->throw_exception("Values for update must be a hash")
1270 unless ref $values eq 'HASH';
1272 carp( 'WARNING! Currently $rs->update() does not generate proper SQL'
1273 . ' on joined resultsets, and may affect rows well outside of the'
1274 . ' contents of $rs. Use at your own risk' )
1275 if ( $self->{attrs}{seen_join} );
1277 my $cond = $self->_cond_for_update_delete;
1279 return $self->result_source->storage->update(
1280 $self->result_source, $values, $cond
1288 =item Arguments: \%values
1290 =item Return Value: 1
1294 Fetches all objects and updates them one at a time. Note that C<update_all>
1295 will run DBIC cascade triggers, while L</update> will not.
1300 my ($self, $values) = @_;
1301 $self->throw_exception("Values for update must be a hash")
1302 unless ref $values eq 'HASH';
1303 foreach my $obj ($self->all) {
1304 $obj->set_columns($values)->update;
1313 =item Arguments: none
1315 =item Return Value: 1
1319 Deletes the contents of the resultset from its result source. Note that this
1320 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1321 to run. See also L<DBIx::Class::Row/delete>.
1323 delete may not generate correct SQL for a query with joins or a resultset
1324 chained from a related resultset. In this case it will generate a warning:-
1326 WARNING! Currently $rs->delete() does not generate proper SQL on
1327 joined resultsets, and may delete rows well outside of the contents
1328 of $rs. Use at your own risk
1330 In these cases you may find that delete_all is more appropriate, or you
1331 need to respecify your query in a way that can be expressed without a join.
1337 $self->throw_exception("Delete should not be passed any arguments")
1339 carp( 'WARNING! Currently $rs->delete() does not generate proper SQL'
1340 . ' on joined resultsets, and may delete rows well outside of the'
1341 . ' contents of $rs. Use at your own risk' )
1342 if ( $self->{attrs}{seen_join} );
1343 my $cond = $self->_cond_for_update_delete;
1345 $self->result_source->storage->delete($self->result_source, $cond);
1353 =item Arguments: none
1355 =item Return Value: 1
1359 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1360 will run DBIC cascade triggers, while L</delete> will not.
1366 $_->delete for $self->all;
1374 =item Arguments: \@data;
1378 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1379 For the arrayref of hashrefs style each hashref should be a structure suitable
1380 forsubmitting to a $resultset->create(...) method.
1382 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1383 to insert the data, as this is a faster method.
1385 Otherwise, each set of data is inserted into the database using
1386 L<DBIx::Class::ResultSet/create>, and a arrayref of the resulting row
1387 objects is returned.
1389 Example: Assuming an Artist Class that has many CDs Classes relating:
1391 my $Artist_rs = $schema->resultset("Artist");
1393 ## Void Context Example
1394 $Artist_rs->populate([
1395 { artistid => 4, name => 'Manufactured Crap', cds => [
1396 { title => 'My First CD', year => 2006 },
1397 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1400 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1401 { title => 'My parents sold me to a record company' ,year => 2005 },
1402 { title => 'Why Am I So Ugly?', year => 2006 },
1403 { title => 'I Got Surgery and am now Popular', year => 2007 }
1408 ## Array Context Example
1409 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1410 { name => "Artist One"},
1411 { name => "Artist Two"},
1412 { name => "Artist Three", cds=> [
1413 { title => "First CD", year => 2007},
1414 { title => "Second CD", year => 2008},
1418 print $ArtistOne->name; ## response is 'Artist One'
1419 print $ArtistThree->cds->count ## reponse is '2'
1421 For the arrayref of arrayrefs style, the first element should be a list of the
1422 fieldsnames to which the remaining elements are rows being inserted. For
1425 $Arstist_rs->populate([
1426 [qw/artistid name/],
1427 [100, 'A Formally Unknown Singer'],
1428 [101, 'A singer that jumped the shark two albums ago'],
1429 [102, 'An actually cool singer.'],
1432 Please note an important effect on your data when choosing between void and
1433 wantarray context. Since void context goes straight to C<insert_bulk> in
1434 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
1435 c<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
1436 create primary keys for you, you will find that your PKs are empty. In this
1437 case you will have to use the wantarray context in order to create those
1443 my $self = shift @_;
1444 my $data = ref $_[0][0] eq 'HASH'
1445 ? $_[0] : ref $_[0][0] eq 'ARRAY' ? $self->_normalize_populate_args($_[0]) :
1446 $self->throw_exception('Populate expects an arrayref of hashes or arrayref of arrayrefs');
1448 if(defined wantarray) {
1450 foreach my $item (@$data) {
1451 push(@created, $self->create($item));
1455 my ($first, @rest) = @$data;
1457 my @names = grep {!ref $first->{$_}} keys %$first;
1458 my @rels = grep { $self->result_source->has_relationship($_) } keys %$first;
1459 my @pks = $self->result_source->primary_columns;
1461 ## do the belongs_to relationships
1462 foreach my $index (0..$#$data) {
1463 if( grep { !defined $data->[$index]->{$_} } @pks ) {
1464 my @ret = $self->populate($data);
1468 foreach my $rel (@rels) {
1469 next unless $data->[$index]->{$rel} && ref $data->[$index]->{$rel} eq "HASH";
1470 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1471 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1472 my $related = $result->result_source->resolve_condition(
1473 $result->result_source->relationship_info($reverse)->{cond},
1478 delete $data->[$index]->{$rel};
1479 $data->[$index] = {%{$data->[$index]}, %$related};
1481 push @names, keys %$related if $index == 0;
1485 ## do bulk insert on current row
1486 my @values = map { [ @$_{@names} ] } @$data;
1488 $self->result_source->storage->insert_bulk(
1489 $self->result_source,
1494 ## do the has_many relationships
1495 foreach my $item (@$data) {
1497 foreach my $rel (@rels) {
1498 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1500 my $parent = $self->find(map {{$_=>$item->{$_}} } @pks)
1501 || $self->throw_exception('Cannot find the relating object.');
1503 my $child = $parent->$rel;
1505 my $related = $child->result_source->resolve_condition(
1506 $parent->result_source->relationship_info($rel)->{cond},
1511 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1512 my @populate = map { {%$_, %$related} } @rows_to_add;
1514 $child->populate( \@populate );
1520 =head2 _normalize_populate_args ($args)
1522 Private method used by L</populate> to normalize its incoming arguments. Factored
1523 out in case you want to subclass and accept new argument structures to the
1524 L</populate> method.
1528 sub _normalize_populate_args {
1529 my ($self, $data) = @_;
1530 my @names = @{shift(@$data)};
1531 my @results_to_create;
1532 foreach my $datum (@$data) {
1533 my %result_to_create;
1534 foreach my $index (0..$#names) {
1535 $result_to_create{$names[$index]} = $$datum[$index];
1537 push @results_to_create, \%result_to_create;
1539 return \@results_to_create;
1546 =item Arguments: none
1548 =item Return Value: $pager
1552 Return Value a L<Data::Page> object for the current resultset. Only makes
1553 sense for queries with a C<page> attribute.
1559 my $attrs = $self->{attrs};
1560 $self->throw_exception("Can't create pager for non-paged rs")
1561 unless $self->{attrs}{page};
1562 $attrs->{rows} ||= 10;
1563 return $self->{pager} ||= Data::Page->new(
1564 $self->_count, $attrs->{rows}, $self->{attrs}{page});
1571 =item Arguments: $page_number
1573 =item Return Value: $rs
1577 Returns a resultset for the $page_number page of the resultset on which page
1578 is called, where each page contains a number of rows equal to the 'rows'
1579 attribute set on the resultset (10 by default).
1584 my ($self, $page) = @_;
1585 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1592 =item Arguments: \%vals
1594 =item Return Value: $rowobject
1598 Creates a new row object in the resultset's result class and returns
1599 it. The row is not inserted into the database at this point, call
1600 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
1601 will tell you whether the row object has been inserted or not.
1603 Passes the hashref of input on to L<DBIx::Class::Row/new>.
1608 my ($self, $values) = @_;
1609 $self->throw_exception( "new_result needs a hash" )
1610 unless (ref $values eq 'HASH');
1613 my $alias = $self->{attrs}{alias};
1616 defined $self->{cond}
1617 && $self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION
1619 %new = %{$self->{attrs}{related_objects}};
1621 $self->throw_exception(
1622 "Can't abstract implicit construct, condition not a hash"
1623 ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
1625 my $collapsed_cond = (
1627 ? $self->_collapse_cond($self->{cond})
1631 # precendence must be given to passed values over values inherited from
1632 # the cond, so the order here is important.
1633 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
1634 while( my($col,$value) = each %implied ){
1635 if(ref($value) eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '='){
1636 $new{$col} = $value->{'='};
1639 $new{$col} = $value if $self->_is_deterministic_value($value);
1645 %{ $self->_remove_alias($values, $alias) },
1646 -source_handle => $self->_source_handle,
1647 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
1650 return $self->result_class->new(\%new);
1653 # _is_deterministic_value
1655 # Make an effor to strip non-deterministic values from the condition,
1656 # to make sure new_result chokes less
1658 sub _is_deterministic_value {
1661 my $ref_type = ref $value;
1662 return 1 if $ref_type eq '' || $ref_type eq 'SCALAR';
1663 return 1 if Scalar::Util::blessed($value);
1669 # Recursively collapse the condition.
1671 sub _collapse_cond {
1672 my ($self, $cond, $collapsed) = @_;
1676 if (ref $cond eq 'ARRAY') {
1677 foreach my $subcond (@$cond) {
1678 next unless ref $subcond; # -or
1679 # warn "ARRAY: " . Dumper $subcond;
1680 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1683 elsif (ref $cond eq 'HASH') {
1684 if (keys %$cond and (keys %$cond)[0] eq '-and') {
1685 foreach my $subcond (@{$cond->{-and}}) {
1686 # warn "HASH: " . Dumper $subcond;
1687 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1691 # warn "LEAF: " . Dumper $cond;
1692 foreach my $col (keys %$cond) {
1693 my $value = $cond->{$col};
1694 $collapsed->{$col} = $value;
1704 # Remove the specified alias from the specified query hash. A copy is made so
1705 # the original query is not modified.
1708 my ($self, $query, $alias) = @_;
1710 my %orig = %{ $query || {} };
1713 foreach my $key (keys %orig) {
1715 $unaliased{$key} = $orig{$key};
1718 $unaliased{$1} = $orig{$key}
1719 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
1729 =item Arguments: \%vals, \%attrs?
1731 =item Return Value: $rowobject
1735 my $artist = $schema->resultset('Artist')->find_or_new(
1736 { artist => 'fred' }, { key => 'artists' });
1738 $cd->cd_to_producer->find_or_new({ producer => $producer },
1739 { key => 'primary });
1741 Find an existing record from this resultset, based on its primary
1742 key, or a unique constraint. If none exists, instantiate a new result
1743 object and return it. The object will not be saved into your storage
1744 until you call L<DBIx::Class::Row/insert> on it.
1746 You most likely want this method when looking for existing rows using
1747 a unique constraint that is not the primary key, or looking for
1750 If you want objects to be saved immediately, use L</find_or_create> instead.
1752 B<Note>: C<find_or_new> is probably not what you want when creating a
1753 new row in a table that uses primary keys supplied by the
1754 database. Passing in a primary key column with a value of I<undef>
1755 will cause L</find> to attempt to search for a row with a value of
1762 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1763 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1764 my $exists = $self->find($hash, $attrs);
1765 return defined $exists ? $exists : $self->new_result($hash);
1772 =item Arguments: \%vals
1774 =item Return Value: a L<DBIx::Class::Row> $object
1778 Attempt to create a single new row or a row with multiple related rows
1779 in the table represented by the resultset (and related tables). This
1780 will not check for duplicate rows before inserting, use
1781 L</find_or_create> to do that.
1783 To create one row for this resultset, pass a hashref of key/value
1784 pairs representing the columns of the table and the values you wish to
1785 store. If the appropriate relationships are set up, foreign key fields
1786 can also be passed an object representing the foreign row, and the
1787 value will be set to its primary key.
1789 To create related objects, pass a hashref for the value if the related
1790 item is a foreign key relationship (L<DBIx::Class::Relationship/belongs_to>),
1791 and use the name of the relationship as the key. (NOT the name of the field,
1792 necessarily). For C<has_many> and C<has_one> relationships, pass an arrayref
1793 of hashrefs containing the data for each of the rows to create in the foreign
1794 tables, again using the relationship name as the key.
1796 Instead of hashrefs of plain related data (key/value pairs), you may
1797 also pass new or inserted objects. New objects (not inserted yet, see
1798 L</new>), will be inserted into their appropriate tables.
1800 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
1802 Example of creating a new row.
1804 $person_rs->create({
1805 name=>"Some Person",
1806 email=>"somebody@someplace.com"
1809 Example of creating a new row and also creating rows in a related C<has_many>
1810 or C<has_one> resultset. Note Arrayref.
1813 { artistid => 4, name => 'Manufactured Crap', cds => [
1814 { title => 'My First CD', year => 2006 },
1815 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1820 Example of creating a new row and also creating a row in a related
1821 C<belongs_to>resultset. Note Hashref.
1824 title=>"Music for Silly Walks",
1827 name=>"Silly Musician",
1834 my ($self, $attrs) = @_;
1835 $self->throw_exception( "create needs a hashref" )
1836 unless ref $attrs eq 'HASH';
1837 return $self->new_result($attrs)->insert;
1840 =head2 find_or_create
1844 =item Arguments: \%vals, \%attrs?
1846 =item Return Value: $rowobject
1850 $cd->cd_to_producer->find_or_create({ producer => $producer },
1851 { key => 'primary });
1853 Tries to find a record based on its primary key or unique constraints; if none
1854 is found, creates one and returns that instead.
1856 my $cd = $schema->resultset('CD')->find_or_create({
1858 artist => 'Massive Attack',
1859 title => 'Mezzanine',
1863 Also takes an optional C<key> attribute, to search by a specific key or unique
1864 constraint. For example:
1866 my $cd = $schema->resultset('CD')->find_or_create(
1868 artist => 'Massive Attack',
1869 title => 'Mezzanine',
1871 { key => 'cd_artist_title' }
1874 B<Note>: Because find_or_create() reads from the database and then
1875 possibly inserts based on the result, this method is subject to a race
1876 condition. Another process could create a record in the table after
1877 the find has completed and before the create has started. To avoid
1878 this problem, use find_or_create() inside a transaction.
1880 B<Note>: C<find_or_create> is probably not what you want when creating
1881 a new row in a table that uses primary keys supplied by the
1882 database. Passing in a primary key column with a value of I<undef>
1883 will cause L</find> to attempt to search for a row with a value of
1886 See also L</find> and L</update_or_create>. For information on how to declare
1887 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1891 sub find_or_create {
1893 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1894 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
1895 my $exists = $self->find($hash, $attrs);
1896 return defined $exists ? $exists : $self->create($hash);
1899 =head2 update_or_create
1903 =item Arguments: \%col_values, { key => $unique_constraint }?
1905 =item Return Value: $rowobject
1909 $resultset->update_or_create({ col => $val, ... });
1911 First, searches for an existing row matching one of the unique constraints
1912 (including the primary key) on the source of this resultset. If a row is
1913 found, updates it with the other given column values. Otherwise, creates a new
1916 Takes an optional C<key> attribute to search on a specific unique constraint.
1919 # In your application
1920 my $cd = $schema->resultset('CD')->update_or_create(
1922 artist => 'Massive Attack',
1923 title => 'Mezzanine',
1926 { key => 'cd_artist_title' }
1929 $cd->cd_to_producer->update_or_create({
1930 producer => $producer,
1937 If no C<key> is specified, it searches on all unique constraints defined on the
1938 source, including the primary key.
1940 If the C<key> is specified as C<primary>, it searches only on the primary key.
1942 See also L</find> and L</find_or_create>. For information on how to declare
1943 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
1945 B<Note>: C<update_or_create> is probably not what you want when
1946 looking for a row in a table that uses primary keys supplied by the
1947 database, unless you actually have a key value. Passing in a primary
1948 key column with a value of I<undef> will cause L</find> to attempt to
1949 search for a row with a value of I<NULL>.
1953 sub update_or_create {
1955 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1956 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
1958 my $row = $self->find($cond, $attrs);
1960 $row->update($cond);
1964 return $self->create($cond);
1971 =item Arguments: none
1973 =item Return Value: \@cache_objects?
1977 Gets the contents of the cache for the resultset, if the cache is set.
1979 The cache is populated either by using the L</prefetch> attribute to
1980 L</search> or by calling L</set_cache>.
1992 =item Arguments: \@cache_objects
1994 =item Return Value: \@cache_objects
1998 Sets the contents of the cache for the resultset. Expects an arrayref
1999 of objects of the same class as those produced by the resultset. Note that
2000 if the cache is set the resultset will return the cached objects rather
2001 than re-querying the database even if the cache attr is not set.
2003 The contents of the cache can also be populated by using the
2004 L</prefetch> attribute to L</search>.
2009 my ( $self, $data ) = @_;
2010 $self->throw_exception("set_cache requires an arrayref")
2011 if defined($data) && (ref $data ne 'ARRAY');
2012 $self->{all_cache} = $data;
2019 =item Arguments: none
2021 =item Return Value: []
2025 Clears the cache for the resultset.
2030 shift->set_cache(undef);
2033 =head2 related_resultset
2037 =item Arguments: $relationship_name
2039 =item Return Value: $resultset
2043 Returns a related resultset for the supplied relationship name.
2045 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2049 sub related_resultset {
2050 my ($self, $rel) = @_;
2052 $self->{related_resultsets} ||= {};
2053 return $self->{related_resultsets}{$rel} ||= do {
2054 my $rel_obj = $self->result_source->relationship_info($rel);
2056 $self->throw_exception(
2057 "search_related: result source '" . $self->result_source->source_name .
2058 "' has no such relationship $rel")
2061 my ($from,$seen) = $self->_resolve_from($rel);
2063 my $join_count = $seen->{$rel};
2064 my $alias = ($join_count > 1 ? join('_', $rel, $join_count) : $rel);
2066 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2067 my %attrs = %{$self->{attrs}||{}};
2068 delete @attrs{qw(result_class alias)};
2072 if (my $cache = $self->get_cache) {
2073 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2074 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
2079 my $rel_source = $self->result_source->related_source($rel);
2083 # The reason we do this now instead of passing the alias to the
2084 # search_rs below is that if you wrap/overload resultset on the
2085 # source you need to know what alias it's -going- to have for things
2086 # to work sanely (e.g. RestrictWithObject wants to be able to add
2087 # extra query restrictions, and these may need to be $alias.)
2089 my $attrs = $rel_source->resultset_attributes;
2090 local $attrs->{alias} = $alias;
2092 $rel_source->resultset
2100 where => $self->{cond},
2105 $new->set_cache($new_cache) if $new_cache;
2110 =head2 current_source_alias
2114 =item Arguments: none
2116 =item Return Value: $source_alias
2120 Returns the current table alias for the result source this resultset is built
2121 on, that will be used in the SQL query. Usually it is C<me>.
2123 Currently the source alias that refers to the result set returned by a
2124 L</search>/L</find> family method depends on how you got to the resultset: it's
2125 C<me> by default, but eg. L</search_related> aliases it to the related result
2126 source name (and keeps C<me> referring to the original result set). The long
2127 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
2128 (and make this method unnecessary).
2130 Thus it's currently necessary to use this method in predefined queries (see
2131 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
2132 source alias of the current result set:
2134 # in a result set class
2136 my ($self, $user) = @_;
2138 my $me = $self->current_source_alias;
2140 return $self->search(
2141 "$me.modified" => $user->id,
2147 sub current_source_alias {
2150 return ($self->{attrs} || {})->{alias} || 'me';
2154 my ($self, $extra_join) = @_;
2155 my $source = $self->result_source;
2156 my $attrs = $self->{attrs};
2158 my $from = $attrs->{from}
2159 || [ { $attrs->{alias} => $source->from } ];
2161 my $seen = { %{$attrs->{seen_join}||{}} };
2163 my $join = ($attrs->{join}
2164 ? [ $attrs->{join}, $extra_join ]
2167 # we need to take the prefetch the attrs into account before we
2168 # ->resolve_join as otherwise they get lost - captainL
2169 my $merged = $self->_merge_attr( $join, $attrs->{prefetch} );
2173 ($join ? $source->resolve_join($merged, $attrs->{alias}, $seen) : ()),
2176 return ($from,$seen);
2179 sub _resolved_attrs {
2181 return $self->{_attrs} if $self->{_attrs};
2183 my $attrs = { %{$self->{attrs}||{}} };
2184 my $source = $self->result_source;
2185 my $alias = $attrs->{alias};
2187 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
2188 if ($attrs->{columns}) {
2189 delete $attrs->{as};
2190 } elsif (!$attrs->{select}) {
2191 $attrs->{columns} = [ $source->columns ];
2196 ? (ref $attrs->{select} eq 'ARRAY'
2197 ? [ @{$attrs->{select}} ]
2198 : [ $attrs->{select} ])
2199 : [ map { m/\./ ? $_ : "${alias}.$_" } @{delete $attrs->{columns}} ]
2203 ? (ref $attrs->{as} eq 'ARRAY'
2204 ? [ @{$attrs->{as}} ]
2206 : [ map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{$attrs->{select}} ]
2210 if ($adds = delete $attrs->{include_columns}) {
2211 $adds = [$adds] unless ref $adds eq 'ARRAY';
2212 push(@{$attrs->{select}}, @$adds);
2213 push(@{$attrs->{as}}, map { m/([^.]+)$/; $1 } @$adds);
2215 if ($adds = delete $attrs->{'+select'}) {
2216 $adds = [$adds] unless ref $adds eq 'ARRAY';
2217 push(@{$attrs->{select}},
2218 map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds);
2220 if (my $adds = delete $attrs->{'+as'}) {
2221 $adds = [$adds] unless ref $adds eq 'ARRAY';
2222 push(@{$attrs->{as}}, @$adds);
2225 $attrs->{from} ||= [ { 'me' => $source->from } ];
2227 if (exists $attrs->{join} || exists $attrs->{prefetch}) {
2228 my $join = delete $attrs->{join} || {};
2230 if (defined $attrs->{prefetch}) {
2231 $join = $self->_merge_attr(
2232 $join, $attrs->{prefetch}
2237 $attrs->{from} = # have to copy here to avoid corrupting the original
2240 $source->resolve_join($join, $alias, { %{$attrs->{seen_join}||{}} })
2245 $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct};
2246 if ($attrs->{order_by}) {
2247 $attrs->{order_by} = (ref($attrs->{order_by}) eq 'ARRAY'
2248 ? [ @{$attrs->{order_by}} ]
2249 : [ $attrs->{order_by} ]);
2251 $attrs->{order_by} = [];
2254 my $collapse = $attrs->{collapse} || {};
2255 if (my $prefetch = delete $attrs->{prefetch}) {
2256 $prefetch = $self->_merge_attr({}, $prefetch);
2258 my $seen = { %{ $attrs->{seen_join} || {} } };
2259 foreach my $p (ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch)) {
2260 # bring joins back to level of current class
2261 my @prefetch = $source->resolve_prefetch(
2262 $p, $alias, $seen, \@pre_order, $collapse
2264 push(@{$attrs->{select}}, map { $_->[0] } @prefetch);
2265 push(@{$attrs->{as}}, map { $_->[1] } @prefetch);
2267 push(@{$attrs->{order_by}}, @pre_order);
2269 $attrs->{collapse} = $collapse;
2271 if ($attrs->{page}) {
2272 $attrs->{offset} ||= 0;
2273 $attrs->{offset} += ($attrs->{rows} * ($attrs->{page} - 1));
2276 return $self->{_attrs} = $attrs;
2280 my ($self, $attr) = @_;
2282 if (ref $attr eq 'HASH') {
2283 return $self->_rollout_hash($attr);
2284 } elsif (ref $attr eq 'ARRAY') {
2285 return $self->_rollout_array($attr);
2291 sub _rollout_array {
2292 my ($self, $attr) = @_;
2295 foreach my $element (@{$attr}) {
2296 if (ref $element eq 'HASH') {
2297 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
2298 } elsif (ref $element eq 'ARRAY') {
2299 # XXX - should probably recurse here
2300 push( @rolled_array, @{$self->_rollout_array($element)} );
2302 push( @rolled_array, $element );
2305 return \@rolled_array;
2309 my ($self, $attr) = @_;
2312 foreach my $key (keys %{$attr}) {
2313 push( @rolled_array, { $key => $attr->{$key} } );
2315 return \@rolled_array;
2318 sub _calculate_score {
2319 my ($self, $a, $b) = @_;
2321 if (ref $b eq 'HASH') {
2322 my ($b_key) = keys %{$b};
2323 if (ref $a eq 'HASH') {
2324 my ($a_key) = keys %{$a};
2325 if ($a_key eq $b_key) {
2326 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
2331 return ($a eq $b_key) ? 1 : 0;
2334 if (ref $a eq 'HASH') {
2335 my ($a_key) = keys %{$a};
2336 return ($b eq $a_key) ? 1 : 0;
2338 return ($b eq $a) ? 1 : 0;
2344 my ($self, $orig, $import) = @_;
2346 return $import unless defined($orig);
2347 return $orig unless defined($import);
2349 $orig = $self->_rollout_attr($orig);
2350 $import = $self->_rollout_attr($import);
2353 foreach my $import_element ( @{$import} ) {
2354 # find best candidate from $orig to merge $b_element into
2355 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
2356 foreach my $orig_element ( @{$orig} ) {
2357 my $score = $self->_calculate_score( $orig_element, $import_element );
2358 if ($score > $best_candidate->{score}) {
2359 $best_candidate->{position} = $position;
2360 $best_candidate->{score} = $score;
2364 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
2366 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
2367 push( @{$orig}, $import_element );
2369 my $orig_best = $orig->[$best_candidate->{position}];
2370 # merge orig_best and b_element together and replace original with merged
2371 if (ref $orig_best ne 'HASH') {
2372 $orig->[$best_candidate->{position}] = $import_element;
2373 } elsif (ref $import_element eq 'HASH') {
2374 my ($key) = keys %{$orig_best};
2375 $orig->[$best_candidate->{position}] = { $key => $self->_merge_attr($orig_best->{$key}, $import_element->{$key}) };
2378 $seen_keys->{$import_key} = 1; # don't merge the same key twice
2388 $self->_source_handle($_[0]->handle);
2390 $self->_source_handle->resolve;
2394 =head2 throw_exception
2396 See L<DBIx::Class::Schema/throw_exception> for details.
2400 sub throw_exception {
2402 if (ref $self && $self->_source_handle->schema) {
2403 $self->_source_handle->schema->throw_exception(@_)
2410 # XXX: FIXME: Attributes docs need clearing up
2414 Attributes are used to refine a ResultSet in various ways when
2415 searching for data. They can be passed to any method which takes an
2416 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
2419 These are in no particular order:
2425 =item Value: ($order_by | \@order_by)
2429 Which column(s) to order the results by. This is currently passed
2430 through directly to SQL, so you can give e.g. C<year DESC> for a
2431 descending order on the column `year'.
2433 Please note that if you have C<quote_char> enabled (see
2434 L<DBIx::Class::Storage::DBI/connect_info>) you will need to do C<\'year DESC' > to
2435 specify an order. (The scalar ref causes it to be passed as raw sql to the DB,
2436 so you will need to manually quote things as appropriate.)
2438 If your L<SQL::Abstract> version supports it (>=1.50), you can also use
2439 C<{-desc => 'year'}>, which takes care of the quoting for you. This is the
2446 =item Value: \@columns
2450 Shortcut to request a particular set of columns to be retrieved. Adds
2451 C<me.> onto the start of any column without a C<.> in it and sets C<select>
2452 from that, then auto-populates C<as> from C<select> as normal. (You may also
2453 use the C<cols> attribute, as in earlier versions of DBIC.)
2455 =head2 include_columns
2459 =item Value: \@columns
2463 Shortcut to include additional columns in the returned results - for example
2465 $schema->resultset('CD')->search(undef, {
2466 include_columns => ['artist.name'],
2470 would return all CDs and include a 'name' column to the information
2471 passed to object inflation. Note that the 'artist' is the name of the
2472 column (or relationship) accessor, and 'name' is the name of the column
2473 accessor in the related table.
2479 =item Value: \@select_columns
2483 Indicates which columns should be selected from the storage. You can use
2484 column names, or in the case of RDBMS back ends, function or stored procedure
2487 $rs = $schema->resultset('Employee')->search(undef, {
2490 { count => 'employeeid' },
2495 When you use function/stored procedure names and do not supply an C<as>
2496 attribute, the column names returned are storage-dependent. E.g. MySQL would
2497 return a column named C<count(employeeid)> in the above example.
2503 Indicates additional columns to be selected from storage. Works the same as
2504 L</select> but adds columns to the selection.
2512 Indicates additional column names for those added via L</+select>. See L</as>.
2520 =item Value: \@inflation_names
2524 Indicates column names for object inflation. That is, C<as>
2525 indicates the name that the column can be accessed as via the
2526 C<get_column> method (or via the object accessor, B<if one already
2527 exists>). It has nothing to do with the SQL code C<SELECT foo AS bar>.
2529 The C<as> attribute is used in conjunction with C<select>,
2530 usually when C<select> contains one or more function or stored
2533 $rs = $schema->resultset('Employee')->search(undef, {
2536 { count => 'employeeid' }
2538 as => ['name', 'employee_count'],
2541 my $employee = $rs->first(); # get the first Employee
2543 If the object against which the search is performed already has an accessor
2544 matching a column name specified in C<as>, the value can be retrieved using
2545 the accessor as normal:
2547 my $name = $employee->name();
2549 If on the other hand an accessor does not exist in the object, you need to
2550 use C<get_column> instead:
2552 my $employee_count = $employee->get_column('employee_count');
2554 You can create your own accessors if required - see
2555 L<DBIx::Class::Manual::Cookbook> for details.
2557 Please note: This will NOT insert an C<AS employee_count> into the SQL
2558 statement produced, it is used for internal access only. Thus
2559 attempting to use the accessor in an C<order_by> clause or similar
2560 will fail miserably.
2562 To get around this limitation, you can supply literal SQL to your
2563 C<select> attibute that contains the C<AS alias> text, eg:
2565 select => [\'myfield AS alias']
2571 =item Value: ($rel_name | \@rel_names | \%rel_names)
2575 Contains a list of relationships that should be joined for this query. For
2578 # Get CDs by Nine Inch Nails
2579 my $rs = $schema->resultset('CD')->search(
2580 { 'artist.name' => 'Nine Inch Nails' },
2581 { join => 'artist' }
2584 Can also contain a hash reference to refer to the other relation's relations.
2587 package MyApp::Schema::Track;
2588 use base qw/DBIx::Class/;
2589 __PACKAGE__->table('track');
2590 __PACKAGE__->add_columns(qw/trackid cd position title/);
2591 __PACKAGE__->set_primary_key('trackid');
2592 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
2595 # In your application
2596 my $rs = $schema->resultset('Artist')->search(
2597 { 'track.title' => 'Teardrop' },
2599 join => { cd => 'track' },
2600 order_by => 'artist.name',
2604 You need to use the relationship (not the table) name in conditions,
2605 because they are aliased as such. The current table is aliased as "me", so
2606 you need to use me.column_name in order to avoid ambiguity. For example:
2608 # Get CDs from 1984 with a 'Foo' track
2609 my $rs = $schema->resultset('CD')->search(
2612 'tracks.name' => 'Foo'
2614 { join => 'tracks' }
2617 If the same join is supplied twice, it will be aliased to <rel>_2 (and
2618 similarly for a third time). For e.g.
2620 my $rs = $schema->resultset('Artist')->search({
2621 'cds.title' => 'Down to Earth',
2622 'cds_2.title' => 'Popular',
2624 join => [ qw/cds cds/ ],
2627 will return a set of all artists that have both a cd with title 'Down
2628 to Earth' and a cd with title 'Popular'.
2630 If you want to fetch related objects from other tables as well, see C<prefetch>
2633 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
2639 =item Value: ($rel_name | \@rel_names | \%rel_names)
2643 Contains one or more relationships that should be fetched along with
2644 the main query (when they are accessed afterwards the data will
2645 already be available, without extra queries to the database). This is
2646 useful for when you know you will need the related objects, because it
2647 saves at least one query:
2649 my $rs = $schema->resultset('Tag')->search(
2658 The initial search results in SQL like the following:
2660 SELECT tag.*, cd.*, artist.* FROM tag
2661 JOIN cd ON tag.cd = cd.cdid
2662 JOIN artist ON cd.artist = artist.artistid
2664 L<DBIx::Class> has no need to go back to the database when we access the
2665 C<cd> or C<artist> relationships, which saves us two SQL statements in this
2668 Simple prefetches will be joined automatically, so there is no need
2669 for a C<join> attribute in the above search.
2671 C<prefetch> can be used with the following relationship types: C<belongs_to>,
2672 C<has_one> (or if you're using C<add_relationship>, any relationship declared
2673 with an accessor type of 'single' or 'filter'). A more complex example that
2674 prefetches an artists cds, the tracks on those cds, and the tags associted
2675 with that artist is given below (assuming many-to-many from artists to tags):
2677 my $rs = $schema->resultset('Artist')->search(
2681 { cds => 'tracks' },
2682 { artist_tags => 'tags' }
2688 B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
2689 attributes will be ignored.
2699 Makes the resultset paged and specifies the page to retrieve. Effectively
2700 identical to creating a non-pages resultset and then calling ->page($page)
2703 If L<rows> attribute is not specified it defualts to 10 rows per page.
2713 Specifes the maximum number of rows for direct retrieval or the number of
2714 rows per page if the page attribute or method is used.
2720 =item Value: $offset
2724 Specifies the (zero-based) row number for the first row to be returned, or the
2725 of the first row of the first page if paging is used.
2731 =item Value: \@columns
2735 A arrayref of columns to group by. Can include columns of joined tables.
2737 group_by => [qw/ column1 column2 ... /]
2743 =item Value: $condition
2747 HAVING is a select statement attribute that is applied between GROUP BY and
2748 ORDER BY. It is applied to the after the grouping calculations have been
2751 having => { 'count(employee)' => { '>=', 100 } }
2757 =item Value: (0 | 1)
2761 Set to 1 to group by all columns.
2767 Adds to the WHERE clause.
2769 # only return rows WHERE deleted IS NULL for all searches
2770 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
2772 Can be overridden by passing C<{ where => undef }> as an attribute
2779 Set to 1 to cache search results. This prevents extra SQL queries if you
2780 revisit rows in your ResultSet:
2782 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
2784 while( my $artist = $resultset->next ) {
2788 $rs->first; # without cache, this would issue a query
2790 By default, searches are not cached.
2792 For more examples of using these attributes, see
2793 L<DBIx::Class::Manual::Cookbook>.
2799 =item Value: \@from_clause
2803 The C<from> attribute gives you manual control over the C<FROM> clause of SQL
2804 statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
2807 NOTE: Use this on your own risk. This allows you to shoot off your foot!
2809 C<join> will usually do what you need and it is strongly recommended that you
2810 avoid using C<from> unless you cannot achieve the desired result using C<join>.
2811 And we really do mean "cannot", not just tried and failed. Attempting to use
2812 this because you're having problems with C<join> is like trying to use x86
2813 ASM because you've got a syntax error in your C. Trust us on this.
2815 Now, if you're still really, really sure you need to use this (and if you're
2816 not 100% sure, ask the mailing list first), here's an explanation of how this
2819 The syntax is as follows -
2822 { <alias1> => <table1> },
2824 { <alias2> => <table2>, -join_type => 'inner|left|right' },
2825 [], # nested JOIN (optional)
2826 { <table1.column1> => <table2.column2>, ... (more conditions) },
2828 # More of the above [ ] may follow for additional joins
2835 ON <table1.column1> = <table2.column2>
2836 <more joins may follow>
2838 An easy way to follow the examples below is to remember the following:
2840 Anything inside "[]" is a JOIN
2841 Anything inside "{}" is a condition for the enclosing JOIN
2843 The following examples utilize a "person" table in a family tree application.
2844 In order to express parent->child relationships, this table is self-joined:
2846 # Person->belongs_to('father' => 'Person');
2847 # Person->belongs_to('mother' => 'Person');
2849 C<from> can be used to nest joins. Here we return all children with a father,
2850 then search against all mothers of those children:
2852 $rs = $schema->resultset('Person')->search(
2855 alias => 'mother', # alias columns in accordance with "from"
2857 { mother => 'person' },
2860 { child => 'person' },
2862 { father => 'person' },
2863 { 'father.person_id' => 'child.father_id' }
2866 { 'mother.person_id' => 'child.mother_id' }
2873 # SELECT mother.* FROM person mother
2876 # JOIN person father
2877 # ON ( father.person_id = child.father_id )
2879 # ON ( mother.person_id = child.mother_id )
2881 The type of any join can be controlled manually. To search against only people
2882 with a father in the person table, we could explicitly use C<INNER JOIN>:
2884 $rs = $schema->resultset('Person')->search(
2887 alias => 'child', # alias columns in accordance with "from"
2889 { child => 'person' },
2891 { father => 'person', -join_type => 'inner' },
2892 { 'father.id' => 'child.father_id' }
2899 # SELECT child.* FROM person child
2900 # INNER JOIN person father ON child.father_id = father.id
2902 If you need to express really complex joins or you need a subselect, you
2903 can supply literal SQL to C<from> via a scalar reference. In this case
2904 the contents of the scalar will replace the table name asscoiated with the
2907 WARNING: This technique might very well not work as expected on chained
2908 searches - you have been warned.
2910 # Assuming the Event resultsource is defined as:
2912 MySchema::Event->add_columns (
2915 is_auto_increment => 1,
2924 MySchema::Event->set_primary_key ('sequence');
2926 # This will get back the latest event for every location. The column
2927 # selector is still provided by DBIC, all we do is add a JOIN/WHERE
2928 # combo to limit the resultset
2930 $rs = $schema->resultset('Event');
2931 $table = $rs->result_source->name;
2932 $latest = $rs->search (
2935 (SELECT e1.* FROM $table e1
2937 ON e1.location = e2.location
2938 AND e1.sequence < e2.sequence
2939 WHERE e2.sequence is NULL
2944 # Equivalent SQL (with the DBIC chunks added):
2946 SELECT me.sequence, me.location, me.type FROM
2947 (SELECT e1.* FROM events e1
2949 ON e1.location = e2.location
2950 AND e1.sequence < e2.sequence
2951 WHERE e2.sequence is NULL
2958 =item Value: ( 'update' | 'shared' )
2962 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT