1 package DBIx::Class::ResultSet;
5 use base qw/DBIx::Class/;
7 use DBIx::Class::ResultSetColumn;
8 use Scalar::Util qw/blessed weaken reftype/;
10 use Data::Compare (); # no imports!!! guard against insane architecture
12 # not importing first() as it will clash with our own method
16 # De-duplication in _merge_attr() is disabled, but left in for reference
17 # (the merger is used for other things that ought not to be de-duped)
18 *__HM_DEDUP = sub () { 0 };
28 # this is real - CDBICompat overrides it with insanity
29 # yes, prototype won't matter, but that's for now ;)
32 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class result_source/);
36 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
40 my $users_rs = $schema->resultset('User');
41 while( $user = $users_rs->next) {
42 print $user->username;
45 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
46 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
50 A ResultSet is an object which stores a set of conditions representing
51 a query. It is the backbone of DBIx::Class (i.e. the really
52 important/useful bit).
54 No SQL is executed on the database when a ResultSet is created, it
55 just stores all the conditions needed to create the query.
57 A basic ResultSet representing the data of an entire table is returned
58 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
59 L<Source|DBIx::Class::Manual::Glossary/Source> name.
61 my $users_rs = $schema->resultset('User');
63 A new ResultSet is returned from calling L</search> on an existing
64 ResultSet. The new one will contain all the conditions of the
65 original, plus any new conditions added in the C<search> call.
67 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
68 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
71 The query that the ResultSet represents is B<only> executed against
72 the database when these methods are called:
73 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
75 If a resultset is used in a numeric context it returns the L</count>.
76 However, if it is used in a boolean context it is B<always> true. So if
77 you want to check if a resultset has any results, you must use C<if $rs
80 =head1 CUSTOM ResultSet CLASSES THAT USE Moose
82 If you want to make your custom ResultSet classes with L<Moose>, use a template
85 package MyApp::Schema::ResultSet::User;
88 use namespace::autoclean;
90 extends 'DBIx::Class::ResultSet';
92 sub BUILDARGS { $_[2] }
96 __PACKAGE__->meta->make_immutable;
100 The L<MooseX::NonMoose> is necessary so that the L<Moose> constructor does not
101 clash with the regular ResultSet constructor. Alternatively, you can use:
103 __PACKAGE__->meta->make_immutable(inline_constructor => 0);
105 The L<BUILDARGS|Moose::Manual::Construction/BUILDARGS> is necessary because the
106 signature of the ResultSet C<new> is C<< ->new($source, \%args) >>.
110 =head2 Chaining resultsets
112 Let's say you've got a query that needs to be run to return some data
113 to the user. But, you have an authorization system in place that
114 prevents certain users from seeing certain information. So, you want
115 to construct the basic query in one method, but add constraints to it in
120 my $request = $self->get_request; # Get a request object somehow.
121 my $schema = $self->result_source->schema;
123 my $cd_rs = $schema->resultset('CD')->search({
124 title => $request->param('title'),
125 year => $request->param('year'),
128 $cd_rs = $self->apply_security_policy( $cd_rs );
130 return $cd_rs->all();
133 sub apply_security_policy {
142 =head3 Resolving conditions and attributes
144 When a resultset is chained from another resultset, conditions and
145 attributes with the same keys need resolving.
147 L</join>, L</prefetch>, L</+select>, L</+as> attributes are merged
148 into the existing ones from the original resultset.
150 The L</where> and L</having> attributes, and any search conditions, are
151 merged with an SQL C<AND> to the existing condition from the original
154 All other attributes are overridden by any new ones supplied in the
157 =head2 Multiple queries
159 Since a resultset just defines a query, you can do all sorts of
160 things with it with the same object.
162 # Don't hit the DB yet.
163 my $cd_rs = $schema->resultset('CD')->search({
164 title => 'something',
168 # Each of these hits the DB individually.
169 my $count = $cd_rs->count;
170 my $most_recent = $cd_rs->get_column('date_released')->max();
171 my @records = $cd_rs->all;
173 And it's not just limited to SELECT statements.
179 $cd_rs->create({ artist => 'Fred' });
181 Which is the same as:
183 $schema->resultset('CD')->create({
184 title => 'something',
189 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
197 =item Arguments: L<$source|DBIx::Class::ResultSource>, L<\%attrs?|/ATTRIBUTES>
199 =item Return Value: L<$resultset|/search>
203 The resultset constructor. Takes a source object (usually a
204 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
205 L</ATTRIBUTES> below). Does not perform any queries -- these are
206 executed as needed by the other methods.
208 Generally you never construct a resultset manually. Instead you get one
210 C<< $schema->L<resultset|DBIx::Class::Schema/resultset>('$source_name') >>
211 or C<< $another_resultset->L<search|/search>(...) >> (the later called in
214 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
220 If called on an object, proxies to L</new_result> instead, so
222 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
224 will return a CD object, not a ResultSet, and is equivalent to:
226 my $cd = $schema->resultset('CD')->new_result({ title => 'Spoon' });
228 Please also keep in mind that many internals call L</new_result> directly,
229 so overloading this method with the idea of intercepting new result object
230 creation B<will not work>. See also warning pertaining to L</create>.
238 return $class->new_result(@_) if ref $class;
240 my ($source, $attrs) = @_;
241 $source = $source->resolve
242 if $source->isa('DBIx::Class::ResultSourceHandle');
243 $attrs = { %{$attrs||{}} };
245 if ($attrs->{page}) {
246 $attrs->{rows} ||= 10;
249 $attrs->{alias} ||= 'me';
252 result_source => $source,
253 cond => $attrs->{where},
258 # if there is a dark selector, this means we are already in a
259 # chain and the cleanup/sanification was taken care of by
261 $self->_normalize_selection($attrs)
262 unless $attrs->{_dark_selector};
265 $attrs->{result_class} || $source->result_class
275 =item Arguments: L<$cond|DBIx::Class::SQLMaker> | undef, L<\%attrs?|/ATTRIBUTES>
277 =item Return Value: $resultset (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
281 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
282 my $new_rs = $cd_rs->search({ year => 2005 });
284 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
285 # year = 2005 OR year = 2004
287 In list context, C<< ->all() >> is called implicitly on the resultset, thus
288 returning a list of L<result|DBIx::Class::Manual::ResultClass> objects instead.
289 To avoid that, use L</search_rs>.
291 If you need to pass in additional attributes but no additional condition,
292 call it as C<search(undef, \%attrs)>.
294 # "SELECT name, artistid FROM $artist_table"
295 my @all_artists = $schema->resultset('Artist')->search(undef, {
296 columns => [qw/name artistid/],
299 For a list of attributes that can be passed to C<search>, see
300 L</ATTRIBUTES>. For more examples of using this function, see
301 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
302 documentation for the first argument, see L<SQL::Abstract>
303 and its extension L<DBIx::Class::SQLMaker>.
305 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
309 Note that L</search> does not process/deflate any of the values passed in the
310 L<SQL::Abstract>-compatible search condition structure. This is unlike other
311 condition-bound methods L</new_result>, L</create> and L</find>. The user must ensure
312 manually that any value passed to this method will stringify to something the
313 RDBMS knows how to deal with. A notable example is the handling of L<DateTime>
314 objects, for more info see:
315 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
321 my $rs = $self->search_rs( @_ );
326 elsif (defined wantarray) {
330 # we can be called by a relationship helper, which in
331 # turn may be called in void context due to some braindead
332 # overload or whatever else the user decided to be clever
333 # at this particular day. Thus limit the exception to
334 # external code calls only
335 $self->throw_exception ('->search is *not* a mutator, calling it in void context makes no sense')
336 if (caller)[0] !~ /^\QDBIx::Class::/;
346 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
348 =item Return Value: L<$resultset|/search>
352 This method does the same exact thing as search() except it will
353 always return a resultset, even in list context.
360 my $rsrc = $self->result_source;
361 my ($call_cond, $call_attrs);
363 # Special-case handling for (undef, undef) or (undef)
364 # Note that (foo => undef) is valid deprecated syntax
365 @_ = () if not scalar grep { defined $_ } @_;
371 # fish out attrs in the ($condref, $attr) case
372 elsif (@_ == 2 and ( ! defined $_[0] or (ref $_[0]) ne '') ) {
373 ($call_cond, $call_attrs) = @_;
376 $self->throw_exception('Odd number of arguments to search')
380 carp_unique 'search( %condition ) is deprecated, use search( \%condition ) instead'
381 unless $rsrc->result_class->isa('DBIx::Class::CDBICompat');
383 for my $i (0 .. $#_) {
385 $self->throw_exception ('All keys in condition key/value pairs must be plain scalars')
386 if (! defined $_[$i] or ref $_[$i] ne '');
392 # see if we can keep the cache (no $rs changes)
394 my %safe = (alias => 1, cache => 1);
395 if ( ! List::Util::first { !$safe{$_} } keys %$call_attrs and (
398 ref $call_cond eq 'HASH' && ! keys %$call_cond
400 ref $call_cond eq 'ARRAY' && ! @$call_cond
402 $cache = $self->get_cache;
405 my $old_attrs = { %{$self->{attrs}} };
406 my $old_having = delete $old_attrs->{having};
407 my $old_where = delete $old_attrs->{where};
409 my $new_attrs = { %$old_attrs };
411 # take care of call attrs (only if anything is changing)
412 if ($call_attrs and keys %$call_attrs) {
414 # copy for _normalize_selection
415 $call_attrs = { %$call_attrs };
417 my @selector_attrs = qw/select as columns cols +select +as +columns include_columns/;
419 # reset the current selector list if new selectors are supplied
420 if (List::Util::first { exists $call_attrs->{$_} } qw/columns cols select as/) {
421 delete @{$old_attrs}{(@selector_attrs, '_dark_selector')};
424 # Normalize the new selector list (operates on the passed-in attr structure)
425 # Need to do it on every chain instead of only once on _resolved_attrs, in
426 # order to allow detection of empty vs partial 'as'
427 $call_attrs->{_dark_selector} = $old_attrs->{_dark_selector}
428 if $old_attrs->{_dark_selector};
429 $self->_normalize_selection ($call_attrs);
431 # start with blind overwriting merge, exclude selector attrs
432 $new_attrs = { %{$old_attrs}, %{$call_attrs} };
433 delete @{$new_attrs}{@selector_attrs};
435 for (@selector_attrs) {
436 $new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
437 if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
440 # older deprecated name, use only if {columns} is not there
441 if (my $c = delete $new_attrs->{cols}) {
442 if ($new_attrs->{columns}) {
443 carp "Resultset specifies both the 'columns' and the legacy 'cols' attributes - ignoring 'cols'";
446 $new_attrs->{columns} = $c;
451 # join/prefetch use their own crazy merging heuristics
452 foreach my $key (qw/join prefetch/) {
453 $new_attrs->{$key} = $self->_merge_joinpref_attr($old_attrs->{$key}, $call_attrs->{$key})
454 if exists $call_attrs->{$key};
457 # stack binds together
458 $new_attrs->{bind} = [ @{ $old_attrs->{bind} || [] }, @{ $call_attrs->{bind} || [] } ];
462 for ($old_where, $call_cond) {
464 $new_attrs->{where} = $self->_stack_cond (
465 $_, $new_attrs->{where}
470 if (defined $old_having) {
471 $new_attrs->{having} = $self->_stack_cond (
472 $old_having, $new_attrs->{having}
476 my $rs = (ref $self)->new($rsrc, $new_attrs);
478 $rs->set_cache($cache) if ($cache);
484 sub _normalize_selection {
485 my ($self, $attrs) = @_;
488 $attrs->{'+columns'} = $self->_merge_attr($attrs->{'+columns'}, delete $attrs->{include_columns})
489 if exists $attrs->{include_columns};
491 # columns are always placed first, however
493 # Keep the X vs +X separation until _resolved_attrs time - this allows to
494 # delay the decision on whether to use a default select list ($rsrc->columns)
495 # allowing stuff like the remove_columns helper to work
497 # select/as +select/+as pairs need special handling - the amount of select/as
498 # elements in each pair does *not* have to be equal (think multicolumn
499 # selectors like distinct(foo, bar) ). If the selector is bare (no 'as'
500 # supplied at all) - try to infer the alias, either from the -as parameter
501 # of the selector spec, or use the parameter whole if it looks like a column
502 # name (ugly legacy heuristic). If all fails - leave the selector bare (which
503 # is ok as well), but make sure no more additions to the 'as' chain take place
504 for my $pref ('', '+') {
506 my ($sel, $as) = map {
507 my $key = "${pref}${_}";
509 my $val = [ ref $attrs->{$key} eq 'ARRAY'
511 : $attrs->{$key} || ()
513 delete $attrs->{$key};
517 if (! @$as and ! @$sel ) {
520 elsif (@$as and ! @$sel) {
521 $self->throw_exception(
522 "Unable to handle ${pref}as specification (@$as) without a corresponding ${pref}select"
526 # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
527 # if any @$as has been supplied we assume the user knows what (s)he is doing
528 # and blindly keep stacking up pieces
529 unless ($attrs->{_dark_selector}) {
532 if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
533 push @$as, $_->{-as};
535 # assume any plain no-space, no-parenthesis string to be a column spec
536 # FIXME - this is retarded but is necessary to support shit like 'count(foo)'
537 elsif ( ! ref $_ and $_ =~ /^ [^\s\(\)]+ $/x) {
540 # if all else fails - raise a flag that no more aliasing will be allowed
542 $attrs->{_dark_selector} = {
544 string => ($dark_sel_dumper ||= do {
545 require Data::Dumper::Concise;
546 Data::Dumper::Concise::DumperObject()->Indent(0);
547 })->Values([$_])->Dump
555 elsif (@$as < @$sel) {
556 $self->throw_exception(
557 "Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
560 elsif ($pref and $attrs->{_dark_selector}) {
561 $self->throw_exception(
562 "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
568 $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
569 $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
574 my ($self, $left, $right) = @_;
576 # collapse single element top-level conditions
577 # (single pass only, unlikely to need recursion)
578 for ($left, $right) {
579 if (ref $_ eq 'ARRAY') {
587 elsif (ref $_ eq 'HASH') {
588 my ($first, $more) = keys %$_;
591 if (! defined $first) {
595 elsif (! defined $more) {
596 if ($first eq '-and' and ref $_->{'-and'} eq 'HASH') {
599 elsif ($first eq '-or' and ref $_->{'-or'} eq 'ARRAY') {
606 # merge hashes with weeding out of duplicates (simple cases only)
607 if (ref $left eq 'HASH' and ref $right eq 'HASH') {
609 # shallow copy to destroy
610 $right = { %$right };
611 for (grep { exists $right->{$_} } keys %$left) {
612 # the use of eq_deeply here is justified - the rhs of an
613 # expression can contain a lot of twisted weird stuff
614 delete $right->{$_} if Data::Compare::Compare( $left->{$_}, $right->{$_} );
617 $right = undef unless keys %$right;
621 if (defined $left xor defined $right) {
622 return defined $left ? $left : $right;
624 elsif (! defined $left) {
628 return { -and => [ $left, $right ] };
632 =head2 search_literal
634 B<CAVEAT>: C<search_literal> is provided for Class::DBI compatibility and
635 should only be used in that context. C<search_literal> is a convenience
636 method. It is equivalent to calling C<< $schema->search(\[]) >>, but if you
637 want to ensure columns are bound correctly, use L</search>.
639 See L<DBIx::Class::Manual::Cookbook/Searching> and
640 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
641 require C<search_literal>.
645 =item Arguments: $sql_fragment, @standalone_bind_values
647 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
651 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
652 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
654 Pass a literal chunk of SQL to be added to the conditional part of the
657 Example of how to use C<search> instead of C<search_literal>
659 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
660 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
665 my ($self, $sql, @bind) = @_;
667 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
670 return $self->search(\[ $sql, map [ {} => $_ ], @bind ], ($attr || () ));
677 =item Arguments: \%columns_values | @pk_values, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
679 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
683 Finds and returns a single row based on supplied criteria. Takes either a
684 hashref with the same format as L</create> (including inference of foreign
685 keys from related objects), or a list of primary key values in the same
686 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
687 declaration on the L</result_source>.
689 In either case an attempt is made to combine conditions already existing on
690 the resultset with the condition passed to this method.
692 To aid with preparing the correct query for the storage you may supply the
693 C<key> attribute, which is the name of a
694 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
695 unique constraint corresponding to the
696 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
697 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
698 to construct a query that satisfies the named unique constraint fully (
699 non-NULL values for each column member of the constraint) an exception is
702 If no C<key> is specified, the search is carried over all unique constraints
703 which are fully defined by the available condition.
705 If no such constraint is found, C<find> currently defaults to a simple
706 C<< search->(\%column_values) >> which may or may not do what you expect.
707 Note that this fallback behavior may be deprecated in further versions. If
708 you need to search with arbitrary conditions - use L</search>. If the query
709 resulting from this fallback produces more than one row, a warning to the
710 effect is issued, though only the first row is constructed and returned as
713 In addition to C<key>, L</find> recognizes and applies standard
714 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
716 Note that if you have extra concerns about the correctness of the resulting
717 query you need to specify the C<key> attribute and supply the entire condition
718 as an argument to find (since it is not always possible to perform the
719 combination of the resultset condition with the supplied one, especially if
720 the resultset condition contains literal sql).
722 For example, to find a row by its primary key:
724 my $cd = $schema->resultset('CD')->find(5);
726 You can also find a row by a specific unique constraint:
728 my $cd = $schema->resultset('CD')->find(
730 artist => 'Massive Attack',
731 title => 'Mezzanine',
733 { key => 'cd_artist_title' }
736 See also L</find_or_create> and L</update_or_create>.
742 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
744 my $rsrc = $self->result_source;
747 if (exists $attrs->{key}) {
748 $constraint_name = defined $attrs->{key}
750 : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
754 # Parse out the condition from input
757 if (ref $_[0] eq 'HASH') {
758 $call_cond = { %{$_[0]} };
761 # if only values are supplied we need to default to 'primary'
762 $constraint_name = 'primary' unless defined $constraint_name;
764 my @c_cols = $rsrc->unique_constraint_columns($constraint_name);
766 $self->throw_exception(
767 "No constraint columns, maybe a malformed '$constraint_name' constraint?"
770 $self->throw_exception (
771 'find() expects either a column/value hashref, or a list of values '
772 . "corresponding to the columns of the specified unique constraint '$constraint_name'"
773 ) unless @c_cols == @_;
776 @{$call_cond}{@c_cols} = @_;
780 for my $key (keys %$call_cond) {
782 my $keyref = ref($call_cond->{$key})
784 my $relinfo = $rsrc->relationship_info($key)
786 my $val = delete $call_cond->{$key};
788 next if $keyref eq 'ARRAY'; # has_many for multi_create
790 my $rel_q = $rsrc->_resolve_condition(
791 $relinfo->{cond}, $val, $key, $key
793 die "Can't handle complex relationship conditions in find" if ref($rel_q) ne 'HASH';
794 @related{keys %$rel_q} = values %$rel_q;
798 # relationship conditions take precedence (?)
799 @{$call_cond}{keys %related} = values %related;
801 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
803 if (defined $constraint_name) {
804 $final_cond = $self->_qualify_cond_columns (
806 $self->_build_unique_cond (
814 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
815 # This means that we got here after a merger of relationship conditions
816 # in ::Relationship::Base::search_related (the row method), and furthermore
817 # the relationship is of the 'single' type. This means that the condition
818 # provided by the relationship (already attached to $self) is sufficient,
819 # as there can be only one row in the database that would satisfy the
823 # no key was specified - fall down to heuristics mode:
824 # run through all unique queries registered on the resultset, and
825 # 'OR' all qualifying queries together
826 my (@unique_queries, %seen_column_combinations);
827 for my $c_name ($rsrc->unique_constraint_names) {
828 next if $seen_column_combinations{
829 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
832 push @unique_queries, try {
833 $self->_build_unique_cond ($c_name, $call_cond, 'croak_on_nulls')
837 $final_cond = @unique_queries
838 ? [ map { $self->_qualify_cond_columns($_, $alias) } @unique_queries ]
839 : $self->_non_unique_find_fallback ($call_cond, $attrs)
843 # Run the query, passing the result_class since it should propagate for find
844 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
845 if (keys %{$rs->_resolved_attrs->{collapse}}) {
847 carp "Query returned more than one row" if $rs->next;
855 # This is a stop-gap method as agreed during the discussion on find() cleanup:
856 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
858 # It is invoked when find() is called in legacy-mode with insufficiently-unique
859 # condition. It is provided for overrides until a saner way forward is devised
861 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
862 # the road. Please adjust your tests accordingly to catch this situation early
863 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
865 # The method will not be removed without an adequately complete replacement
866 # for strict-mode enforcement
867 sub _non_unique_find_fallback {
868 my ($self, $cond, $attrs) = @_;
870 return $self->_qualify_cond_columns(
872 exists $attrs->{alias}
874 : $self->{attrs}{alias}
879 sub _qualify_cond_columns {
880 my ($self, $cond, $alias) = @_;
882 my %aliased = %$cond;
883 for (keys %aliased) {
884 $aliased{"$alias.$_"} = delete $aliased{$_}
891 sub _build_unique_cond {
892 my ($self, $constraint_name, $extra_cond, $croak_on_null) = @_;
894 my @c_cols = $self->result_source->unique_constraint_columns($constraint_name);
896 # combination may fail if $self->{cond} is non-trivial
897 my ($final_cond) = try {
898 $self->_merge_with_rscond ($extra_cond)
903 # trim out everything not in $columns
904 $final_cond = { map {
905 exists $final_cond->{$_}
906 ? ( $_ => $final_cond->{$_} )
910 if (my @missing = grep
911 { ! ($croak_on_null ? defined $final_cond->{$_} : exists $final_cond->{$_}) }
914 $self->throw_exception( sprintf ( "Unable to satisfy requested constraint '%s', no values for column(s): %s",
916 join (', ', map { "'$_'" } @missing),
923 !$ENV{DBIC_NULLABLE_KEY_NOWARN}
925 my @undefs = sort grep { ! defined $final_cond->{$_} } (keys %$final_cond)
927 carp_unique ( sprintf (
928 "NULL/undef values supplied for requested unique constraint '%s' (NULL "
929 . 'values in column(s): %s). This is almost certainly not what you wanted, '
930 . 'though you can set DBIC_NULLABLE_KEY_NOWARN to disable this warning.',
932 join (', ', map { "'$_'" } @undefs),
939 =head2 search_related
943 =item Arguments: $rel_name, $cond?, L<\%attrs?|/ATTRIBUTES>
945 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
949 $new_rs = $cd_rs->search_related('artist', {
953 Searches the specified relationship, optionally specifying a condition and
954 attributes for matching records. See L</ATTRIBUTES> for more information.
956 In list context, C<< ->all() >> is called implicitly on the resultset, thus
957 returning a list of result objects instead. To avoid that, use L</search_related_rs>.
959 See also L</search_related_rs>.
964 return shift->related_resultset(shift)->search(@_);
967 =head2 search_related_rs
969 This method works exactly the same as search_related, except that
970 it guarantees a resultset, even in list context.
974 sub search_related_rs {
975 return shift->related_resultset(shift)->search_rs(@_);
982 =item Arguments: none
984 =item Return Value: L<$cursor|DBIx::Class::Cursor>
988 Returns a storage-driven cursor to the given resultset. See
989 L<DBIx::Class::Cursor> for more information.
996 return $self->{cursor} ||= do {
997 my $attrs = { %{$self->_resolved_attrs } };
998 $self->result_source->storage->select(
999 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
1008 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1010 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1014 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1016 Inflates the first result without creating a cursor if the resultset has
1017 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1020 While this method can take an optional search condition (just like L</search>)
1021 being a fast-code-path it does not recognize search attributes. If you need to
1022 add extra joins or similar, call L</search> and then chain-call L</single> on the
1023 L<DBIx::Class::ResultSet> returned.
1029 As of 0.08100, this method enforces the assumption that the preceding
1030 query returns only one row. If more than one row is returned, you will receive
1033 Query returned more than one row
1035 In this case, you should be using L</next> or L</find> instead, or if you really
1036 know what you are doing, use the L</rows> attribute to explicitly limit the size
1039 This method will also throw an exception if it is called on a resultset prefetching
1040 has_many, as such a prefetch implies fetching multiple rows from the database in
1041 order to assemble the resulting object.
1048 my ($self, $where) = @_;
1050 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1053 my $attrs = { %{$self->_resolved_attrs} };
1055 if (keys %{$attrs->{collapse}}) {
1056 $self->throw_exception(
1057 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
1062 if (defined $attrs->{where}) {
1065 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1066 $where, delete $attrs->{where} ]
1069 $attrs->{where} = $where;
1073 my @data = $self->result_source->storage->select_single(
1074 $attrs->{from}, $attrs->{select},
1075 $attrs->{where}, $attrs
1078 return (@data ? ($self->_construct_object(@data))[0] : undef);
1084 # Recursively collapse the query, accumulating values for each column.
1086 sub _collapse_query {
1087 my ($self, $query, $collapsed) = @_;
1091 if (ref $query eq 'ARRAY') {
1092 foreach my $subquery (@$query) {
1093 next unless ref $subquery; # -or
1094 $collapsed = $self->_collapse_query($subquery, $collapsed);
1097 elsif (ref $query eq 'HASH') {
1098 if (keys %$query and (keys %$query)[0] eq '-and') {
1099 foreach my $subquery (@{$query->{-and}}) {
1100 $collapsed = $self->_collapse_query($subquery, $collapsed);
1104 foreach my $col (keys %$query) {
1105 my $value = $query->{$col};
1106 $collapsed->{$col}{$value}++;
1118 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1120 =item Return Value: L<$resultsetcolumn|DBIx::Class::ResultSetColumn>
1124 my $max_length = $rs->get_column('length')->max;
1126 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1131 my ($self, $column) = @_;
1132 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
1140 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1142 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1146 # WHERE title LIKE '%blue%'
1147 $cd_rs = $rs->search_like({ title => '%blue%'});
1149 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1150 that this is simply a convenience method retained for ex Class::DBI users.
1151 You most likely want to use L</search> with specific operators.
1153 For more information, see L<DBIx::Class::Manual::Cookbook>.
1155 This method is deprecated and will be removed in 0.09. Use L</search()>
1156 instead. An example conversion is:
1158 ->search_like({ foo => 'bar' });
1162 ->search({ foo => { like => 'bar' } });
1169 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1170 .' Instead use ->search({ x => { -like => "y%" } })'
1171 .' (note the outer pair of {}s - they are important!)'
1173 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1174 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1175 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1176 return $class->search($query, { %$attrs });
1183 =item Arguments: $first, $last
1185 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1189 Returns a resultset or object list representing a subset of elements from the
1190 resultset slice is called on. Indexes are from 0, i.e., to get the first
1191 three records, call:
1193 my ($one, $two, $three) = $rs->slice(0, 2);
1198 my ($self, $min, $max) = @_;
1199 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1200 $attrs->{offset} = $self->{attrs}{offset} || 0;
1201 $attrs->{offset} += $min;
1202 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1203 return $self->search(undef, $attrs);
1204 #my $slice = (ref $self)->new($self->result_source, $attrs);
1205 #return (wantarray ? $slice->all : $slice);
1212 =item Arguments: none
1214 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1218 Returns the next element in the resultset (C<undef> is there is none).
1220 Can be used to efficiently iterate over records in the resultset:
1222 my $rs = $schema->resultset('CD')->search;
1223 while (my $cd = $rs->next) {
1227 Note that you need to store the resultset object, and call C<next> on it.
1228 Calling C<< resultset('Table')->next >> repeatedly will always return the
1229 first record from the resultset.
1235 if (my $cache = $self->get_cache) {
1236 $self->{all_cache_position} ||= 0;
1237 return $cache->[$self->{all_cache_position}++];
1239 if ($self->{attrs}{cache}) {
1240 delete $self->{pager};
1241 $self->{all_cache_position} = 1;
1242 return ($self->all)[0];
1244 if ($self->{stashed_objects}) {
1245 my $obj = shift(@{$self->{stashed_objects}});
1246 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
1250 exists $self->{stashed_row}
1251 ? @{delete $self->{stashed_row}}
1252 : $self->cursor->next
1254 return undef unless (@row);
1255 my ($row, @more) = $self->_construct_object(@row);
1256 $self->{stashed_objects} = \@more if @more;
1260 sub _construct_object {
1261 my ($self, @row) = @_;
1263 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row)
1265 my @new = $self->result_class->inflate_result($self->result_source, @$info);
1266 @new = $self->{_attrs}{record_filter}->(@new)
1267 if exists $self->{_attrs}{record_filter};
1271 sub _collapse_result {
1272 my ($self, $as_proto, $row) = @_;
1276 # 'foo' => [ undef, 'foo' ]
1277 # 'foo.bar' => [ 'foo', 'bar' ]
1278 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
1280 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
1282 my %collapse = %{$self->{_attrs}{collapse}||{}};
1286 # if we're doing collapsing (has_many prefetch) we need to grab records
1287 # until the PK changes, so fill @pri_index. if not, we leave it empty so
1288 # we know we don't have to bother.
1290 # the reason for not using the collapse stuff directly is because if you
1291 # had for e.g. two artists in a row with no cds, the collapse info for
1292 # both would be NULL (undef) so you'd lose the second artist
1294 # store just the index so we can check the array positions from the row
1295 # without having to contruct the full hash
1297 if (keys %collapse) {
1298 my %pri = map { ($_ => 1) } $self->result_source->_pri_cols;
1299 foreach my $i (0 .. $#construct_as) {
1300 next if defined($construct_as[$i][0]); # only self table
1301 if (delete $pri{$construct_as[$i][1]}) {
1302 push(@pri_index, $i);
1304 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
1308 # no need to do an if, it'll be empty if @pri_index is empty anyway
1310 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
1314 do { # no need to check anything at the front, we always want the first row
1318 foreach my $this_as (@construct_as) {
1319 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
1322 push(@const_rows, \%const);
1324 } until ( # no pri_index => no collapse => drop straight out
1327 do { # get another row, stash it, drop out if different PK
1329 @copy = $self->cursor->next;
1330 $self->{stashed_row} = \@copy;
1332 # last thing in do block, counts as true if anything doesn't match
1334 # check xor defined first for NULL vs. NOT NULL then if one is
1335 # defined the other must be so check string equality
1338 (defined $pri_vals{$_} ^ defined $copy[$_])
1339 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
1344 my $alias = $self->{attrs}{alias};
1351 foreach my $const (@const_rows) {
1352 scalar @const_keys or do {
1353 @const_keys = sort { length($a) <=> length($b) } keys %$const;
1355 foreach my $key (@const_keys) {
1358 my @parts = split(/\./, $key);
1360 my $data = $const->{$key};
1361 foreach my $p (@parts) {
1362 $target = $target->[1]->{$p} ||= [];
1364 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
1365 # collapsing at this point and on final part
1366 my $pos = $collapse_pos{$cur};
1367 CK: foreach my $ck (@ckey) {
1368 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
1369 $collapse_pos{$cur} = $data;
1370 delete @collapse_pos{ # clear all positioning for sub-entries
1371 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
1378 if (exists $collapse{$cur}) {
1379 $target = $target->[-1];
1382 $target->[0] = $data;
1384 $info->[0] = $const->{$key};
1392 =head2 result_source
1396 =item Arguments: L<$result_source?|DBIx::Class::ResultSource>
1398 =item Return Value: L<$result_source|DBIx::Class::ResultSource>
1402 An accessor for the primary ResultSource object from which this ResultSet
1409 =item Arguments: $result_class?
1411 =item Return Value: $result_class
1415 An accessor for the class to use when creating result objects. Defaults to
1416 C<< result_source->result_class >> - which in most cases is the name of the
1417 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1419 Note that changing the result_class will also remove any components
1420 that were originally loaded in the source class via
1421 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1422 in the original source class will not run.
1427 my ($self, $result_class) = @_;
1428 if ($result_class) {
1429 unless (ref $result_class) { # don't fire this for an object
1430 $self->ensure_class_loaded($result_class);
1432 $self->_result_class($result_class);
1433 # THIS LINE WOULD BE A BUG - this accessor specifically exists to
1434 # permit the user to set result class on one result set only; it only
1435 # chains if provided to search()
1436 #$self->{attrs}{result_class} = $result_class if ref $self;
1438 $self->_result_class;
1445 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1447 =item Return Value: $count
1451 Performs an SQL C<COUNT> with the same query as the resultset was built
1452 with to find the number of elements. Passing arguments is equivalent to
1453 C<< $rs->search ($cond, \%attrs)->count >>
1459 return $self->search(@_)->count if @_ and defined $_[0];
1460 return scalar @{ $self->get_cache } if $self->get_cache;
1462 my $attrs = { %{ $self->_resolved_attrs } };
1464 # this is a little optimization - it is faster to do the limit
1465 # adjustments in software, instead of a subquery
1466 my $rows = delete $attrs->{rows};
1467 my $offset = delete $attrs->{offset};
1470 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1471 $crs = $self->_count_subq_rs ($attrs);
1474 $crs = $self->_count_rs ($attrs);
1476 my $count = $crs->next;
1478 $count -= $offset if $offset;
1479 $count = $rows if $rows and $rows < $count;
1480 $count = 0 if ($count < 0);
1489 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1491 =item Return Value: L<$count_rs|DBIx::Class::ResultSetColumn>
1495 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1496 This can be very handy for subqueries:
1498 ->search( { amount => $some_rs->count_rs->as_query } )
1500 As with regular resultsets the SQL query will be executed only after
1501 the resultset is accessed via L</next> or L</all>. That would return
1502 the same single value obtainable via L</count>.
1508 return $self->search(@_)->count_rs if @_;
1510 # this may look like a lack of abstraction (count() does about the same)
1511 # but in fact an _rs *must* use a subquery for the limits, as the
1512 # software based limiting can not be ported if this $rs is to be used
1513 # in a subquery itself (i.e. ->as_query)
1514 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1515 return $self->_count_subq_rs;
1518 return $self->_count_rs;
1523 # returns a ResultSetColumn object tied to the count query
1526 my ($self, $attrs) = @_;
1528 my $rsrc = $self->result_source;
1529 $attrs ||= $self->_resolved_attrs;
1531 my $tmp_attrs = { %$attrs };
1532 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1533 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1535 # overwrite the selector (supplied by the storage)
1536 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $attrs);
1537 $tmp_attrs->{as} = 'count';
1538 delete @{$tmp_attrs}{qw/columns/};
1540 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1546 # same as above but uses a subquery
1548 sub _count_subq_rs {
1549 my ($self, $attrs) = @_;
1551 my $rsrc = $self->result_source;
1552 $attrs ||= $self->_resolved_attrs;
1554 my $sub_attrs = { %$attrs };
1555 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1556 delete @{$sub_attrs}{qw/collapse columns as select _prefetch_selector_range order_by for/};
1558 # if we multi-prefetch we group_by something unique, as this is what we would
1559 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1560 if ( keys %{$attrs->{collapse}} ) {
1561 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1562 $rsrc->_identifying_column_set || $self->throw_exception(
1563 'Unable to construct a unique group_by criteria properly collapsing the '
1564 . 'has_many prefetch before count()'
1569 # Calculate subquery selector
1570 if (my $g = $sub_attrs->{group_by}) {
1572 my $sql_maker = $rsrc->storage->sql_maker;
1574 # necessary as the group_by may refer to aliased functions
1576 for my $sel (@{$attrs->{select}}) {
1577 $sel_index->{$sel->{-as}} = $sel
1578 if (ref $sel eq 'HASH' and $sel->{-as});
1581 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1582 # also look for named aggregates referred in the having clause
1583 # having often contains scalarrefs - thus parse it out entirely
1585 if ($attrs->{having}) {
1586 local $sql_maker->{having_bind};
1587 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1588 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1589 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1590 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1591 # if we don't unset it we screw up retarded but unfortunately working
1592 # 'MAX(foo.bar)' => { '>', 3 }
1593 $sql_maker->{name_sep} = '';
1596 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1598 my $having_sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1601 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1602 # and if all fails for an utterly naive quoted scalar-with-function
1603 while ($having_sql =~ /
1604 $rquote $sep $lquote (.+?) $rquote
1606 [\s,] \w+ \. (\w+) [\s,]
1608 [\s,] $lquote (.+?) $rquote [\s,]
1610 my $part = $1 || $2 || $3; # one of them matched if we got here
1611 unless ($seen_having{$part}++) {
1618 my $colpiece = $sel_index->{$_} || $_;
1620 # unqualify join-based group_by's. Arcane but possible query
1621 # also horrible horrible hack to alias a column (not a func.)
1622 # (probably need to introduce SQLA syntax)
1623 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1626 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1628 push @{$sub_attrs->{select}}, $colpiece;
1632 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1633 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1636 return $rsrc->resultset_class
1637 ->new ($rsrc, $sub_attrs)
1639 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1640 ->get_column ('count');
1644 =head2 count_literal
1646 B<CAVEAT>: C<count_literal> is provided for Class::DBI compatibility and
1647 should only be used in that context. See L</search_literal> for further info.
1651 =item Arguments: $sql_fragment, @standalone_bind_values
1653 =item Return Value: $count
1657 Counts the results in a literal query. Equivalent to calling L</search_literal>
1658 with the passed arguments, then L</count>.
1662 sub count_literal { shift->search_literal(@_)->count; }
1668 =item Arguments: none
1670 =item Return Value: L<@result_objs|DBIx::Class::Manual::ResultClass>
1674 Returns all elements in the resultset.
1681 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1684 return @{ $self->get_cache } if $self->get_cache;
1688 if (keys %{$self->_resolved_attrs->{collapse}}) {
1689 # Using $self->cursor->all is really just an optimisation.
1690 # If we're collapsing has_many prefetches it probably makes
1691 # very little difference, and this is cleaner than hacking
1692 # _construct_object to survive the approach
1693 $self->cursor->reset;
1694 my @row = $self->cursor->next;
1696 push(@obj, $self->_construct_object(@row));
1697 @row = (exists $self->{stashed_row}
1698 ? @{delete $self->{stashed_row}}
1699 : $self->cursor->next);
1702 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1705 $self->set_cache(\@obj) if $self->{attrs}{cache};
1714 =item Arguments: none
1716 =item Return Value: $self
1720 Resets the resultset's cursor, so you can iterate through the elements again.
1721 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1728 $self->{all_cache_position} = 0;
1729 $self->cursor->reset;
1737 =item Arguments: none
1739 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1743 L<Resets|/reset> the resultset (causing a fresh query to storage) and returns
1744 an object for the first result (or C<undef> if the resultset is empty).
1749 return $_[0]->reset->next;
1755 # Determines whether and what type of subquery is required for the $rs operation.
1756 # If grouping is necessary either supplies its own, or verifies the current one
1757 # After all is done delegates to the proper storage method.
1759 sub _rs_update_delete {
1760 my ($self, $op, $values) = @_;
1762 my $rsrc = $self->result_source;
1763 my $storage = $rsrc->schema->storage;
1765 my $attrs = { %{$self->_resolved_attrs} };
1767 my $join_classifications;
1768 my $existing_group_by = delete $attrs->{group_by};
1770 # do we need a subquery for any reason?
1772 defined $existing_group_by
1774 # if {from} is unparseable wrap a subq
1775 ref($attrs->{from}) ne 'ARRAY'
1777 # limits call for a subq
1778 $self->_has_resolved_attr(qw/rows offset/)
1781 # simplify the joinmap, so we can further decide if a subq is necessary
1782 if (!$needs_subq and @{$attrs->{from}} > 1) {
1783 $attrs->{from} = $storage->_prune_unused_joins ($attrs->{from}, $attrs->{select}, $self->{cond}, $attrs);
1785 # check if there are any joins left after the prune
1786 if ( @{$attrs->{from}} > 1 ) {
1787 $join_classifications = $storage->_resolve_aliastypes_from_select_args (
1788 [ @{$attrs->{from}}[1 .. $#{$attrs->{from}}] ],
1794 # any non-pruneable joins imply subq
1795 $needs_subq = scalar keys %{ $join_classifications->{restricting} || {} };
1799 # check if the head is composite (by now all joins are thrown out unless $needs_subq)
1801 (ref $attrs->{from}[0]) ne 'HASH'
1803 ref $attrs->{from}[0]{ $attrs->{from}[0]{-alias} }
1807 # do we need anything like a subquery?
1808 if (! $needs_subq) {
1809 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1810 # a condition containing 'me' or other table prefixes will not work
1811 # at all. Tell SQLMaker to dequalify idents via a gross hack.
1813 my $sqla = $rsrc->storage->sql_maker;
1814 local $sqla->{_dequalify_idents} = 1;
1815 \[ $sqla->_recurse_where($self->{cond}) ];
1819 # we got this far - means it is time to wrap a subquery
1820 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1822 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1828 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1829 delete $attrs->{$_} for qw/collapse _collapse_order_by select _prefetch_selector_range as/;
1830 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1831 $attrs->{group_by} = \ ''; # FIXME - this is an evil hack, it causes the optimiser to kick in and throw away the LEFT joins
1832 my $subrs = (ref $self)->new($rsrc, $attrs);
1834 if (@$idcols == 1) {
1835 $cond = { $idcols->[0] => { -in => $subrs->as_query } };
1837 elsif ($storage->_use_multicolumn_in) {
1838 # no syntax for calling this properly yet
1839 # !!! EXPERIMENTAL API !!! WILL CHANGE !!!
1840 $cond = $storage->sql_maker->_where_op_multicolumn_in (
1841 $idcols, # how do I convey a list of idents...? can binds reside on lhs?
1846 # if all else fails - get all primary keys and operate over a ORed set
1847 # wrap in a transaction for consistency
1848 # this is where the group_by/multiplication starts to matter
1852 keys %{ $join_classifications->{multiplying} || {} }
1854 # make sure if there is a supplied group_by it matches the columns compiled above
1855 # perfectly. Anything else can not be sanely executed on most databases so croak
1856 # right then and there
1857 if ($existing_group_by) {
1858 my @current_group_by = map
1859 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1864 join ("\x00", sort @current_group_by)
1866 join ("\x00", sort @{$attrs->{columns}} )
1868 $self->throw_exception (
1869 "You have just attempted a $op operation on a resultset which does group_by"
1870 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1871 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1872 . ' kind of queries. Please retry the operation with a modified group_by or'
1873 . ' without using one at all.'
1878 $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
1881 $guard = $storage->txn_scope_guard;
1884 for my $row ($subrs->cursor->all) {
1886 { $idcols->[$_] => $row->[$_] }
1893 my $res = $storage->$op (
1895 $op eq 'update' ? $values : (),
1899 $guard->commit if $guard;
1908 =item Arguments: \%values
1910 =item Return Value: $underlying_storage_rv
1914 Sets the specified columns in the resultset to the supplied values in a
1915 single query. Note that this will not run any accessor/set_column/update
1916 triggers, nor will it update any result object instances derived from this
1917 resultset (this includes the contents of the L<resultset cache|/set_cache>
1918 if any). See L</update_all> if you need to execute any on-update
1919 triggers or cascades defined either by you or a
1920 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1922 The return value is a pass through of what the underlying
1923 storage backend returned, and may vary. See L<DBI/execute> for the most
1928 Note that L</update> does not process/deflate any of the values passed in.
1929 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
1930 ensure manually that any value passed to this method will stringify to
1931 something the RDBMS knows how to deal with. A notable example is the
1932 handling of L<DateTime> objects, for more info see:
1933 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
1938 my ($self, $values) = @_;
1939 $self->throw_exception('Values for update must be a hash')
1940 unless ref $values eq 'HASH';
1942 return $self->_rs_update_delete ('update', $values);
1949 =item Arguments: \%values
1951 =item Return Value: 1
1955 Fetches all objects and updates them one at a time via
1956 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
1957 triggers, while L</update> will not.
1962 my ($self, $values) = @_;
1963 $self->throw_exception('Values for update_all must be a hash')
1964 unless ref $values eq 'HASH';
1966 my $guard = $self->result_source->schema->txn_scope_guard;
1967 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
1976 =item Arguments: none
1978 =item Return Value: $underlying_storage_rv
1982 Deletes the rows matching this resultset in a single query. Note that this
1983 will not run any delete triggers, nor will it alter the
1984 L<in_storage|DBIx::Class::Row/in_storage> status of any result object instances
1985 derived from this resultset (this includes the contents of the
1986 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
1987 execute any on-delete triggers or cascades defined either by you or a
1988 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1990 The return value is a pass through of what the underlying storage backend
1991 returned, and may vary. See L<DBI/execute> for the most common case.
1997 $self->throw_exception('delete does not accept any arguments')
2000 return $self->_rs_update_delete ('delete');
2007 =item Arguments: none
2009 =item Return Value: 1
2013 Fetches all objects and deletes them one at a time via
2014 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2015 triggers, while L</delete> will not.
2021 $self->throw_exception('delete_all does not accept any arguments')
2024 my $guard = $self->result_source->schema->txn_scope_guard;
2025 $_->delete for $self->all;
2034 =item Arguments: [ \@column_list, \@row_values+ ] | [ \%col_data+ ]
2036 =item Return Value: L<\@result_objects|DBIx::Class::Manual::ResultClass> (scalar context) | L<@result_objects|DBIx::Class::Manual::ResultClass> (list context)
2040 Accepts either an arrayref of hashrefs or alternatively an arrayref of
2047 The context of this method call has an important effect on what is
2048 submitted to storage. In void context data is fed directly to fastpath
2049 insertion routines provided by the underlying storage (most often
2050 L<DBI/execute_for_fetch>), bypassing the L<new|DBIx::Class::Row/new> and
2051 L<insert|DBIx::Class::Row/insert> calls on the
2052 L<Result|DBIx::Class::Manual::ResultClass> class, including any
2053 augmentation of these methods provided by components. For example if you
2054 are using something like L<DBIx::Class::UUIDColumns> to create primary
2055 keys for you, you will find that your PKs are empty. In this case you
2056 will have to explicitly force scalar or list context in order to create
2061 In non-void (scalar or list) context, this method is simply a wrapper
2062 for L</create>. Depending on list or scalar context either a list of
2063 L<Result|DBIx::Class::Manual::ResultClass> objects or an arrayref
2064 containing these objects is returned.
2066 When supplying data in "arrayref of arrayrefs" invocation style, the
2067 first element should be a list of column names and each subsequent
2068 element should be a data value in the earlier specified column order.
2071 $Arstist_rs->populate([
2072 [ qw( artistid name ) ],
2073 [ 100, 'A Formally Unknown Singer' ],
2074 [ 101, 'A singer that jumped the shark two albums ago' ],
2075 [ 102, 'An actually cool singer' ],
2078 For the arrayref of hashrefs style each hashref should be a structure
2079 suitable for passing to L</create>. Multi-create is also permitted with
2082 $schema->resultset("Artist")->populate([
2083 { artistid => 4, name => 'Manufactured Crap', cds => [
2084 { title => 'My First CD', year => 2006 },
2085 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2088 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2089 { title => 'My parents sold me to a record company', year => 2005 },
2090 { title => 'Why Am I So Ugly?', year => 2006 },
2091 { title => 'I Got Surgery and am now Popular', year => 2007 }
2096 If you attempt a void-context multi-create as in the example above (each
2097 Artist also has the related list of CDs), and B<do not> supply the
2098 necessary autoinc foreign key information, this method will proxy to the
2099 less efficient L</create>, and then throw the Result objects away. In this
2100 case there are obviously no benefits to using this method over L</create>.
2107 # cruft placed in standalone method
2108 my $data = $self->_normalize_populate_args(@_);
2110 return unless @$data;
2112 if(defined wantarray) {
2113 my @created = map { $self->create($_) } @$data;
2114 return wantarray ? @created : \@created;
2117 my $first = $data->[0];
2119 # if a column is a registered relationship, and is a non-blessed hash/array, consider
2120 # it relationship data
2121 my (@rels, @columns);
2122 my $rsrc = $self->result_source;
2123 my $rels = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2124 for (keys %$first) {
2125 my $ref = ref $first->{$_};
2126 $rels->{$_} && ($ref eq 'ARRAY' or $ref eq 'HASH')
2132 my @pks = $rsrc->primary_columns;
2134 ## do the belongs_to relationships
2135 foreach my $index (0..$#$data) {
2137 # delegate to create() for any dataset without primary keys with specified relationships
2138 if (grep { !defined $data->[$index]->{$_} } @pks ) {
2140 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
2141 my @ret = $self->populate($data);
2147 foreach my $rel (@rels) {
2148 next unless ref $data->[$index]->{$rel} eq "HASH";
2149 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
2150 my ($reverse_relname, $reverse_relinfo) = %{$rsrc->reverse_relationship_info($rel)};
2151 my $related = $result->result_source->_resolve_condition(
2152 $reverse_relinfo->{cond},
2158 delete $data->[$index]->{$rel};
2159 $data->[$index] = {%{$data->[$index]}, %$related};
2161 push @columns, keys %$related if $index == 0;
2165 ## inherit the data locked in the conditions of the resultset
2166 my ($rs_data) = $self->_merge_with_rscond({});
2167 delete @{$rs_data}{@columns};
2169 ## do bulk insert on current row
2170 $rsrc->storage->insert_bulk(
2172 [@columns, keys %$rs_data],
2173 [ map { [ @$_{@columns}, values %$rs_data ] } @$data ],
2176 ## do the has_many relationships
2177 foreach my $item (@$data) {
2181 foreach my $rel (@rels) {
2182 next unless ref $item->{$rel} eq "ARRAY" && @{ $item->{$rel} };
2184 $main_row ||= $self->new_result({map { $_ => $item->{$_} } @pks});
2186 my $child = $main_row->$rel;
2188 my $related = $child->result_source->_resolve_condition(
2189 $rels->{$rel}{cond},
2195 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
2196 my @populate = map { {%$_, %$related} } @rows_to_add;
2198 $child->populate( \@populate );
2205 # populate() argumnets went over several incarnations
2206 # What we ultimately support is AoH
2207 sub _normalize_populate_args {
2208 my ($self, $arg) = @_;
2210 if (ref $arg eq 'ARRAY') {
2214 elsif (ref $arg->[0] eq 'HASH') {
2217 elsif (ref $arg->[0] eq 'ARRAY') {
2219 my @colnames = @{$arg->[0]};
2220 foreach my $values (@{$arg}[1 .. $#$arg]) {
2221 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
2227 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2234 =item Arguments: none
2236 =item Return Value: L<$pager|Data::Page>
2240 Returns a L<Data::Page> object for the current resultset. Only makes
2241 sense for queries with a C<page> attribute.
2243 To get the full count of entries for a paged resultset, call
2244 C<total_entries> on the L<Data::Page> object.
2251 return $self->{pager} if $self->{pager};
2253 my $attrs = $self->{attrs};
2254 if (!defined $attrs->{page}) {
2255 $self->throw_exception("Can't create pager for non-paged rs");
2257 elsif ($attrs->{page} <= 0) {
2258 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2260 $attrs->{rows} ||= 10;
2262 # throw away the paging flags and re-run the count (possibly
2263 # with a subselect) to get the real total count
2264 my $count_attrs = { %$attrs };
2265 delete $count_attrs->{$_} for qw/rows offset page pager/;
2267 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2269 require DBIx::Class::ResultSet::Pager;
2270 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2271 sub { $total_rs->count }, #lazy-get the total
2273 $self->{attrs}{page},
2281 =item Arguments: $page_number
2283 =item Return Value: L<$resultset|/search>
2287 Returns a resultset for the $page_number page of the resultset on which page
2288 is called, where each page contains a number of rows equal to the 'rows'
2289 attribute set on the resultset (10 by default).
2294 my ($self, $page) = @_;
2295 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2302 =item Arguments: \%col_data
2304 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2308 Creates a new result object in the resultset's result class and returns
2309 it. The row is not inserted into the database at this point, call
2310 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2311 will tell you whether the result object has been inserted or not.
2313 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2318 my ($self, $values) = @_;
2320 $self->throw_exception( "new_result takes only one argument - a hashref of values" )
2323 $self->throw_exception( "new_result expects a hashref" )
2324 unless (ref $values eq 'HASH');
2326 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2328 my $new = $self->result_class->new({
2330 ( @$cols_from_relations
2331 ? (-cols_from_relations => $cols_from_relations)
2334 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2338 reftype($new) eq 'HASH'
2344 carp_unique (sprintf (
2345 "%s->new returned a blessed empty hashref - a strong indicator something is wrong with its inheritance chain",
2346 $self->result_class,
2353 # _merge_with_rscond
2355 # Takes a simple hash of K/V data and returns its copy merged with the
2356 # condition already present on the resultset. Additionally returns an
2357 # arrayref of value/condition names, which were inferred from related
2358 # objects (this is needed for in-memory related objects)
2359 sub _merge_with_rscond {
2360 my ($self, $data) = @_;
2362 my (%new_data, @cols_from_relations);
2364 my $alias = $self->{attrs}{alias};
2366 if (! defined $self->{cond}) {
2367 # just massage $data below
2369 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
2370 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
2371 @cols_from_relations = keys %new_data;
2373 elsif (ref $self->{cond} ne 'HASH') {
2374 $self->throw_exception(
2375 "Can't abstract implicit construct, resultset condition not a hash"
2379 # precendence must be given to passed values over values inherited from
2380 # the cond, so the order here is important.
2381 my $collapsed_cond = $self->_collapse_cond($self->{cond});
2382 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
2384 while ( my($col, $value) = each %implied ) {
2385 my $vref = ref $value;
2391 (keys %$value)[0] eq '='
2393 $new_data{$col} = $value->{'='};
2395 elsif( !$vref or $vref eq 'SCALAR' or blessed($value) ) {
2396 $new_data{$col} = $value;
2403 %{ $self->_remove_alias($data, $alias) },
2406 return (\%new_data, \@cols_from_relations);
2409 # _has_resolved_attr
2411 # determines if the resultset defines at least one
2412 # of the attributes supplied
2414 # used to determine if a subquery is neccessary
2416 # supports some virtual attributes:
2418 # This will scan for any joins being present on the resultset.
2419 # It is not a mere key-search but a deep inspection of {from}
2422 sub _has_resolved_attr {
2423 my ($self, @attr_names) = @_;
2425 my $attrs = $self->_resolved_attrs;
2429 for my $n (@attr_names) {
2430 if (grep { $n eq $_ } (qw/-join/) ) {
2431 $extra_checks{$n}++;
2435 my $attr = $attrs->{$n};
2437 next if not defined $attr;
2439 if (ref $attr eq 'HASH') {
2440 return 1 if keys %$attr;
2442 elsif (ref $attr eq 'ARRAY') {
2450 # a resolved join is expressed as a multi-level from
2452 $extra_checks{-join}
2454 ref $attrs->{from} eq 'ARRAY'
2456 @{$attrs->{from}} > 1
2464 # Recursively collapse the condition.
2466 sub _collapse_cond {
2467 my ($self, $cond, $collapsed) = @_;
2471 if (ref $cond eq 'ARRAY') {
2472 foreach my $subcond (@$cond) {
2473 next unless ref $subcond; # -or
2474 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2477 elsif (ref $cond eq 'HASH') {
2478 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2479 foreach my $subcond (@{$cond->{-and}}) {
2480 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2484 foreach my $col (keys %$cond) {
2485 my $value = $cond->{$col};
2486 $collapsed->{$col} = $value;
2496 # Remove the specified alias from the specified query hash. A copy is made so
2497 # the original query is not modified.
2500 my ($self, $query, $alias) = @_;
2502 my %orig = %{ $query || {} };
2505 foreach my $key (keys %orig) {
2507 $unaliased{$key} = $orig{$key};
2510 $unaliased{$1} = $orig{$key}
2511 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2521 =item Arguments: none
2523 =item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
2527 Returns the SQL query and bind vars associated with the invocant.
2529 This is generally used as the RHS for a subquery.
2536 my $attrs = { %{ $self->_resolved_attrs } };
2541 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2542 # $sql also has no wrapping parenthesis in list ctx
2544 my $sqlbind = $self->result_source->storage
2545 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2554 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2556 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2560 my $artist = $schema->resultset('Artist')->find_or_new(
2561 { artist => 'fred' }, { key => 'artists' });
2563 $cd->cd_to_producer->find_or_new({ producer => $producer },
2564 { key => 'primary });
2566 Find an existing record from this resultset using L</find>. if none exists,
2567 instantiate a new result object and return it. The object will not be saved
2568 into your storage until you call L<DBIx::Class::Row/insert> on it.
2570 You most likely want this method when looking for existing rows using a unique
2571 constraint that is not the primary key, or looking for related rows.
2573 If you want objects to be saved immediately, use L</find_or_create> instead.
2575 B<Note>: Make sure to read the documentation of L</find> and understand the
2576 significance of the C<key> attribute, as its lack may skew your search, and
2577 subsequently result in spurious new objects.
2579 B<Note>: Take care when using C<find_or_new> with a table having
2580 columns with default values that you intend to be automatically
2581 supplied by the database (e.g. an auto_increment primary key column).
2582 In normal usage, the value of such columns should NOT be included at
2583 all in the call to C<find_or_new>, even when set to C<undef>.
2589 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2590 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2591 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2594 return $self->new_result($hash);
2601 =item Arguments: \%col_data
2603 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2607 Attempt to create a single new row or a row with multiple related rows
2608 in the table represented by the resultset (and related tables). This
2609 will not check for duplicate rows before inserting, use
2610 L</find_or_create> to do that.
2612 To create one row for this resultset, pass a hashref of key/value
2613 pairs representing the columns of the table and the values you wish to
2614 store. If the appropriate relationships are set up, foreign key fields
2615 can also be passed an object representing the foreign row, and the
2616 value will be set to its primary key.
2618 To create related objects, pass a hashref of related-object column values
2619 B<keyed on the relationship name>. If the relationship is of type C<multi>
2620 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2621 The process will correctly identify columns holding foreign keys, and will
2622 transparently populate them from the keys of the corresponding relation.
2623 This can be applied recursively, and will work correctly for a structure
2624 with an arbitrary depth and width, as long as the relationships actually
2625 exists and the correct column data has been supplied.
2627 Instead of hashrefs of plain related data (key/value pairs), you may
2628 also pass new or inserted objects. New objects (not inserted yet, see
2629 L</new_result>), will be inserted into their appropriate tables.
2631 Effectively a shortcut for C<< ->new_result(\%col_data)->insert >>.
2633 Example of creating a new row.
2635 $person_rs->create({
2636 name=>"Some Person",
2637 email=>"somebody@someplace.com"
2640 Example of creating a new row and also creating rows in a related C<has_many>
2641 or C<has_one> resultset. Note Arrayref.
2644 { artistid => 4, name => 'Manufactured Crap', cds => [
2645 { title => 'My First CD', year => 2006 },
2646 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2651 Example of creating a new row and also creating a row in a related
2652 C<belongs_to> resultset. Note Hashref.
2655 title=>"Music for Silly Walks",
2658 name=>"Silly Musician",
2666 When subclassing ResultSet never attempt to override this method. Since
2667 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2668 lot of the internals simply never call it, so your override will be
2669 bypassed more often than not. Override either L<DBIx::Class::Row/new>
2670 or L<DBIx::Class::Row/insert> depending on how early in the
2671 L</create> process you need to intervene. See also warning pertaining to
2679 my ($self, $attrs) = @_;
2680 $self->throw_exception( "create needs a hashref" )
2681 unless ref $attrs eq 'HASH';
2682 return $self->new_result($attrs)->insert;
2685 =head2 find_or_create
2689 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2691 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2695 $cd->cd_to_producer->find_or_create({ producer => $producer },
2696 { key => 'primary' });
2698 Tries to find a record based on its primary key or unique constraints; if none
2699 is found, creates one and returns that instead.
2701 my $cd = $schema->resultset('CD')->find_or_create({
2703 artist => 'Massive Attack',
2704 title => 'Mezzanine',
2708 Also takes an optional C<key> attribute, to search by a specific key or unique
2709 constraint. For example:
2711 my $cd = $schema->resultset('CD')->find_or_create(
2713 artist => 'Massive Attack',
2714 title => 'Mezzanine',
2716 { key => 'cd_artist_title' }
2719 B<Note>: Make sure to read the documentation of L</find> and understand the
2720 significance of the C<key> attribute, as its lack may skew your search, and
2721 subsequently result in spurious row creation.
2723 B<Note>: Because find_or_create() reads from the database and then
2724 possibly inserts based on the result, this method is subject to a race
2725 condition. Another process could create a record in the table after
2726 the find has completed and before the create has started. To avoid
2727 this problem, use find_or_create() inside a transaction.
2729 B<Note>: Take care when using C<find_or_create> with a table having
2730 columns with default values that you intend to be automatically
2731 supplied by the database (e.g. an auto_increment primary key column).
2732 In normal usage, the value of such columns should NOT be included at
2733 all in the call to C<find_or_create>, even when set to C<undef>.
2735 See also L</find> and L</update_or_create>. For information on how to declare
2736 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2738 If you need to know if an existing row was found or a new one created use
2739 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2740 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2743 my $cd = $schema->resultset('CD')->find_or_new({
2745 artist => 'Massive Attack',
2746 title => 'Mezzanine',
2750 if( !$cd->in_storage ) {
2757 sub find_or_create {
2759 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2760 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2761 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2764 return $self->create($hash);
2767 =head2 update_or_create
2771 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2773 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2777 $resultset->update_or_create({ col => $val, ... });
2779 Like L</find_or_create>, but if a row is found it is immediately updated via
2780 C<< $found_row->update (\%col_data) >>.
2783 Takes an optional C<key> attribute to search on a specific unique constraint.
2786 # In your application
2787 my $cd = $schema->resultset('CD')->update_or_create(
2789 artist => 'Massive Attack',
2790 title => 'Mezzanine',
2793 { key => 'cd_artist_title' }
2796 $cd->cd_to_producer->update_or_create({
2797 producer => $producer,
2803 B<Note>: Make sure to read the documentation of L</find> and understand the
2804 significance of the C<key> attribute, as its lack may skew your search, and
2805 subsequently result in spurious row creation.
2807 B<Note>: Take care when using C<update_or_create> with a table having
2808 columns with default values that you intend to be automatically
2809 supplied by the database (e.g. an auto_increment primary key column).
2810 In normal usage, the value of such columns should NOT be included at
2811 all in the call to C<update_or_create>, even when set to C<undef>.
2813 See also L</find> and L</find_or_create>. For information on how to declare
2814 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2816 If you need to know if an existing row was updated or a new one created use
2817 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2818 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2823 sub update_or_create {
2825 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2826 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2828 my $row = $self->find($cond, $attrs);
2830 $row->update($cond);
2834 return $self->create($cond);
2837 =head2 update_or_new
2841 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2843 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2847 $resultset->update_or_new({ col => $val, ... });
2849 Like L</find_or_new> but if a row is found it is immediately updated via
2850 C<< $found_row->update (\%col_data) >>.
2854 # In your application
2855 my $cd = $schema->resultset('CD')->update_or_new(
2857 artist => 'Massive Attack',
2858 title => 'Mezzanine',
2861 { key => 'cd_artist_title' }
2864 if ($cd->in_storage) {
2865 # the cd was updated
2868 # the cd is not yet in the database, let's insert it
2872 B<Note>: Make sure to read the documentation of L</find> and understand the
2873 significance of the C<key> attribute, as its lack may skew your search, and
2874 subsequently result in spurious new objects.
2876 B<Note>: Take care when using C<update_or_new> with a table having
2877 columns with default values that you intend to be automatically
2878 supplied by the database (e.g. an auto_increment primary key column).
2879 In normal usage, the value of such columns should NOT be included at
2880 all in the call to C<update_or_new>, even when set to C<undef>.
2882 See also L</find>, L</find_or_create> and L</find_or_new>.
2888 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2889 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2891 my $row = $self->find( $cond, $attrs );
2892 if ( defined $row ) {
2893 $row->update($cond);
2897 return $self->new_result($cond);
2904 =item Arguments: none
2906 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass> | undef
2910 Gets the contents of the cache for the resultset, if the cache is set.
2912 The cache is populated either by using the L</prefetch> attribute to
2913 L</search> or by calling L</set_cache>.
2925 =item Arguments: L<\@result_objs|DBIx::Class::Manual::ResultClass>
2927 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass>
2931 Sets the contents of the cache for the resultset. Expects an arrayref
2932 of objects of the same class as those produced by the resultset. Note that
2933 if the cache is set, the resultset will return the cached objects rather
2934 than re-querying the database even if the cache attr is not set.
2936 The contents of the cache can also be populated by using the
2937 L</prefetch> attribute to L</search>.
2942 my ( $self, $data ) = @_;
2943 $self->throw_exception("set_cache requires an arrayref")
2944 if defined($data) && (ref $data ne 'ARRAY');
2945 $self->{all_cache} = $data;
2952 =item Arguments: none
2954 =item Return Value: undef
2958 Clears the cache for the resultset.
2963 shift->set_cache(undef);
2970 =item Arguments: none
2972 =item Return Value: true, if the resultset has been paginated
2980 return !!$self->{attrs}{page};
2987 =item Arguments: none
2989 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2997 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
3000 =head2 related_resultset
3004 =item Arguments: $rel_name
3006 =item Return Value: L<$resultset|/search>
3010 Returns a related resultset for the supplied relationship name.
3012 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
3016 sub related_resultset {
3017 my ($self, $rel) = @_;
3019 $self->{related_resultsets} ||= {};
3020 return $self->{related_resultsets}{$rel} ||= do {
3021 my $rsrc = $self->result_source;
3022 my $rel_info = $rsrc->relationship_info($rel);
3024 $self->throw_exception(
3025 "search_related: result source '" . $rsrc->source_name .
3026 "' has no such relationship $rel")
3029 my $attrs = $self->_chain_relationship($rel);
3031 my $join_count = $attrs->{seen_join}{$rel};
3033 my $alias = $self->result_source->storage
3034 ->relname_to_table_alias($rel, $join_count);
3036 # since this is search_related, and we already slid the select window inwards
3037 # (the select/as attrs were deleted in the beginning), we need to flip all
3038 # left joins to inner, so we get the expected results
3039 # read the comment on top of the actual function to see what this does
3040 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
3043 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3044 delete @{$attrs}{qw(result_class alias)};
3048 if (my $cache = $self->get_cache) {
3049 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
3050 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
3055 my $rel_source = $rsrc->related_source($rel);
3059 # The reason we do this now instead of passing the alias to the
3060 # search_rs below is that if you wrap/overload resultset on the
3061 # source you need to know what alias it's -going- to have for things
3062 # to work sanely (e.g. RestrictWithObject wants to be able to add
3063 # extra query restrictions, and these may need to be $alias.)
3065 my $rel_attrs = $rel_source->resultset_attributes;
3066 local $rel_attrs->{alias} = $alias;
3068 $rel_source->resultset
3072 where => $attrs->{where},
3075 $new->set_cache($new_cache) if $new_cache;
3080 =head2 current_source_alias
3084 =item Arguments: none
3086 =item Return Value: $source_alias
3090 Returns the current table alias for the result source this resultset is built
3091 on, that will be used in the SQL query. Usually it is C<me>.
3093 Currently the source alias that refers to the result set returned by a
3094 L</search>/L</find> family method depends on how you got to the resultset: it's
3095 C<me> by default, but eg. L</search_related> aliases it to the related result
3096 source name (and keeps C<me> referring to the original result set). The long
3097 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3098 (and make this method unnecessary).
3100 Thus it's currently necessary to use this method in predefined queries (see
3101 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3102 source alias of the current result set:
3104 # in a result set class
3106 my ($self, $user) = @_;
3108 my $me = $self->current_source_alias;
3110 return $self->search({
3111 "$me.modified" => $user->id,
3117 sub current_source_alias {
3118 return (shift->{attrs} || {})->{alias} || 'me';
3121 =head2 as_subselect_rs
3125 =item Arguments: none
3127 =item Return Value: L<$resultset|/search>
3131 Act as a barrier to SQL symbols. The resultset provided will be made into a
3132 "virtual view" by including it as a subquery within the from clause. From this
3133 point on, any joined tables are inaccessible to ->search on the resultset (as if
3134 it were simply where-filtered without joins). For example:
3136 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3138 # 'x' now pollutes the query namespace
3140 # So the following works as expected
3141 my $ok_rs = $rs->search({'x.other' => 1});
3143 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3144 # def) we look for one row with contradictory terms and join in another table
3145 # (aliased 'x_2') which we never use
3146 my $broken_rs = $rs->search({'x.name' => 'def'});
3148 my $rs2 = $rs->as_subselect_rs;
3150 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3151 my $not_joined_rs = $rs2->search({'x.other' => 1});
3153 # works as expected: finds a 'table' row related to two x rows (abc and def)
3154 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3156 Another example of when one might use this would be to select a subset of
3157 columns in a group by clause:
3159 my $rs = $schema->resultset('Bar')->search(undef, {
3160 group_by => [qw{ id foo_id baz_id }],
3161 })->as_subselect_rs->search(undef, {
3162 columns => [qw{ id foo_id }]
3165 In the above example normally columns would have to be equal to the group by,
3166 but because we isolated the group by into a subselect the above works.
3170 sub as_subselect_rs {
3173 my $attrs = $self->_resolved_attrs;
3175 my $fresh_rs = (ref $self)->new (
3176 $self->result_source
3179 # these pieces will be locked in the subquery
3180 delete $fresh_rs->{cond};
3181 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3183 return $fresh_rs->search( {}, {
3185 $attrs->{alias} => $self->as_query,
3186 -alias => $attrs->{alias},
3187 -rsrc => $self->result_source,
3189 alias => $attrs->{alias},
3193 # This code is called by search_related, and makes sure there
3194 # is clear separation between the joins before, during, and
3195 # after the relationship. This information is needed later
3196 # in order to properly resolve prefetch aliases (any alias
3197 # with a relation_chain_depth less than the depth of the
3198 # current prefetch is not considered)
3200 # The increments happen twice per join. An even number means a
3201 # relationship specified via a search_related, whereas an odd
3202 # number indicates a join/prefetch added via attributes
3204 # Also this code will wrap the current resultset (the one we
3205 # chain to) in a subselect IFF it contains limiting attributes
3206 sub _chain_relationship {
3207 my ($self, $rel) = @_;
3208 my $source = $self->result_source;
3209 my $attrs = { %{$self->{attrs}||{}} };
3211 # we need to take the prefetch the attrs into account before we
3212 # ->_resolve_join as otherwise they get lost - captainL
3213 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3215 delete @{$attrs}{qw/join prefetch collapse group_by distinct select as columns +select +as +columns/};
3217 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3220 my @force_subq_attrs = qw/offset rows group_by having/;
3223 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3225 $self->_has_resolved_attr (@force_subq_attrs)
3227 # Nuke the prefetch (if any) before the new $rs attrs
3228 # are resolved (prefetch is useless - we are wrapping
3229 # a subquery anyway).
3230 my $rs_copy = $self->search;
3231 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3232 $rs_copy->{attrs}{join},
3233 delete $rs_copy->{attrs}{prefetch},
3238 -alias => $attrs->{alias},
3239 $attrs->{alias} => $rs_copy->as_query,
3241 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3242 $seen->{-relation_chain_depth} = 0;
3244 elsif ($attrs->{from}) { #shallow copy suffices
3245 $from = [ @{$attrs->{from}} ];
3250 -alias => $attrs->{alias},
3251 $attrs->{alias} => $source->from,
3255 my $jpath = ($seen->{-relation_chain_depth})
3256 ? $from->[-1][0]{-join_path}
3259 my @requested_joins = $source->_resolve_join(
3266 push @$from, @requested_joins;
3268 $seen->{-relation_chain_depth}++;
3270 # if $self already had a join/prefetch specified on it, the requested
3271 # $rel might very well be already included. What we do in this case
3272 # is effectively a no-op (except that we bump up the chain_depth on
3273 # the join in question so we could tell it *is* the search_related)
3276 # we consider the last one thus reverse
3277 for my $j (reverse @requested_joins) {
3278 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3279 if ($rel eq $last_j) {
3280 $j->[0]{-relation_chain_depth}++;
3286 unless ($already_joined) {
3287 push @$from, $source->_resolve_join(
3295 $seen->{-relation_chain_depth}++;
3297 return {%$attrs, from => $from, seen_join => $seen};
3300 sub _resolved_attrs {
3302 return $self->{_attrs} if $self->{_attrs};
3304 my $attrs = { %{ $self->{attrs} || {} } };
3305 my $source = $self->result_source;
3306 my $alias = $attrs->{alias};
3308 # default selection list
3309 $attrs->{columns} = [ $source->columns ]
3310 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3312 # merge selectors together
3313 for (qw/columns select as/) {
3314 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3315 if $attrs->{$_} or $attrs->{"+$_"};
3318 # disassemble columns
3320 if (my $cols = delete $attrs->{columns}) {
3321 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3322 if (ref $c eq 'HASH') {
3323 for my $as (sort keys %$c) {
3324 push @sel, $c->{$as};
3335 # when trying to weed off duplicates later do not go past this point -
3336 # everything added from here on is unbalanced "anyone's guess" stuff
3337 my $dedup_stop_idx = $#as;
3339 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3341 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3342 if $attrs->{select};
3344 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3346 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_";
3349 # disqualify all $alias.col as-bits (collapser mandated)
3351 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_;
3354 # de-duplicate the result (remove *identical* select/as pairs)
3355 # and also die on duplicate {as} pointing to different {select}s
3356 # not using a c-style for as the condition is prone to shrinkage
3359 while ($i <= $dedup_stop_idx) {
3360 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3365 elsif ($seen->{$as[$i]}++) {
3366 $self->throw_exception(
3367 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3375 $attrs->{select} = \@sel;
3376 $attrs->{as} = \@as;
3378 $attrs->{from} ||= [{
3380 -alias => $self->{attrs}{alias},
3381 $self->{attrs}{alias} => $source->from,
3384 if ( $attrs->{join} || $attrs->{prefetch} ) {
3386 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3387 if ref $attrs->{from} ne 'ARRAY';
3389 my $join = (delete $attrs->{join}) || {};
3391 if ( defined $attrs->{prefetch} ) {
3392 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3395 $attrs->{from} = # have to copy here to avoid corrupting the original
3397 @{ $attrs->{from} },
3398 $source->_resolve_join(
3401 { %{ $attrs->{seen_join} || {} } },
3402 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3403 ? $attrs->{from}[-1][0]{-join_path}
3410 if ( defined $attrs->{order_by} ) {
3411 $attrs->{order_by} = (
3412 ref( $attrs->{order_by} ) eq 'ARRAY'
3413 ? [ @{ $attrs->{order_by} } ]
3414 : [ $attrs->{order_by} || () ]
3418 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3419 $attrs->{group_by} = [ $attrs->{group_by} ];
3422 # generate the distinct induced group_by early, as prefetch will be carried via a
3423 # subquery (since a group_by is present)
3424 if (delete $attrs->{distinct}) {
3425 if ($attrs->{group_by}) {
3426 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3429 # distinct affects only the main selection part, not what prefetch may
3431 $attrs->{group_by} = $source->storage->_group_over_selection (
3439 $attrs->{collapse} ||= {};
3440 if ($attrs->{prefetch}) {
3442 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3443 if $attrs->{_dark_selector};
3445 my $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} );
3447 my $prefetch_ordering = [];
3449 # this is a separate structure (we don't look in {from} directly)
3450 # as the resolver needs to shift things off the lists to work
3451 # properly (identical-prefetches on different branches)
3453 if (ref $attrs->{from} eq 'ARRAY') {
3455 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3457 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3458 next unless $j->[0]{-alias};
3459 next unless $j->[0]{-join_path};
3460 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3462 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3465 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3466 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3471 $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
3473 # we need to somehow mark which columns came from prefetch
3475 my $sel_end = $#{$attrs->{select}};
3476 $attrs->{_prefetch_selector_range} = [ $sel_end + 1, $sel_end + @prefetch ];
3479 push @{ $attrs->{select} }, (map { $_->[0] } @prefetch);
3480 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
3482 push( @{$attrs->{order_by}}, @$prefetch_ordering );
3483 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
3486 # if both page and offset are specified, produce a combined offset
3487 # even though it doesn't make much sense, this is what pre 081xx has
3489 if (my $page = delete $attrs->{page}) {
3491 ($attrs->{rows} * ($page - 1))
3493 ($attrs->{offset} || 0)
3497 return $self->{_attrs} = $attrs;
3501 my ($self, $attr) = @_;
3503 if (ref $attr eq 'HASH') {
3504 return $self->_rollout_hash($attr);
3505 } elsif (ref $attr eq 'ARRAY') {
3506 return $self->_rollout_array($attr);
3512 sub _rollout_array {
3513 my ($self, $attr) = @_;
3516 foreach my $element (@{$attr}) {
3517 if (ref $element eq 'HASH') {
3518 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3519 } elsif (ref $element eq 'ARRAY') {
3520 # XXX - should probably recurse here
3521 push( @rolled_array, @{$self->_rollout_array($element)} );
3523 push( @rolled_array, $element );
3526 return \@rolled_array;
3530 my ($self, $attr) = @_;
3533 foreach my $key (keys %{$attr}) {
3534 push( @rolled_array, { $key => $attr->{$key} } );
3536 return \@rolled_array;
3539 sub _calculate_score {
3540 my ($self, $a, $b) = @_;
3542 if (defined $a xor defined $b) {
3545 elsif (not defined $a) {
3549 if (ref $b eq 'HASH') {
3550 my ($b_key) = keys %{$b};
3551 if (ref $a eq 'HASH') {
3552 my ($a_key) = keys %{$a};
3553 if ($a_key eq $b_key) {
3554 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3559 return ($a eq $b_key) ? 1 : 0;
3562 if (ref $a eq 'HASH') {
3563 my ($a_key) = keys %{$a};
3564 return ($b eq $a_key) ? 1 : 0;
3566 return ($b eq $a) ? 1 : 0;
3571 sub _merge_joinpref_attr {
3572 my ($self, $orig, $import) = @_;
3574 return $import unless defined($orig);
3575 return $orig unless defined($import);
3577 $orig = $self->_rollout_attr($orig);
3578 $import = $self->_rollout_attr($import);
3581 foreach my $import_element ( @{$import} ) {
3582 # find best candidate from $orig to merge $b_element into
3583 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3584 foreach my $orig_element ( @{$orig} ) {
3585 my $score = $self->_calculate_score( $orig_element, $import_element );
3586 if ($score > $best_candidate->{score}) {
3587 $best_candidate->{position} = $position;
3588 $best_candidate->{score} = $score;
3592 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3593 $import_key = '' if not defined $import_key;
3595 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3596 push( @{$orig}, $import_element );
3598 my $orig_best = $orig->[$best_candidate->{position}];
3599 # merge orig_best and b_element together and replace original with merged
3600 if (ref $orig_best ne 'HASH') {
3601 $orig->[$best_candidate->{position}] = $import_element;
3602 } elsif (ref $import_element eq 'HASH') {
3603 my ($key) = keys %{$orig_best};
3604 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3607 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3618 require Hash::Merge;
3619 my $hm = Hash::Merge->new;
3621 $hm->specify_behavior({
3624 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3626 if ($defl xor $defr) {
3627 return [ $defl ? $_[0] : $_[1] ];
3632 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3636 return [$_[0], $_[1]];
3640 return $_[1] if !defined $_[0];
3641 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3642 return [$_[0], @{$_[1]}]
3645 return [] if !defined $_[0] and !keys %{$_[1]};
3646 return [ $_[1] ] if !defined $_[0];
3647 return [ $_[0] ] if !keys %{$_[1]};
3648 return [$_[0], $_[1]]
3653 return $_[0] if !defined $_[1];
3654 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3655 return [@{$_[0]}, $_[1]]
3658 my @ret = @{$_[0]} or return $_[1];
3659 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3660 my %idx = map { $_ => 1 } @ret;
3661 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3665 return [ $_[1] ] if ! @{$_[0]};
3666 return $_[0] if !keys %{$_[1]};
3667 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3668 return [ @{$_[0]}, $_[1] ];
3673 return [] if !keys %{$_[0]} and !defined $_[1];
3674 return [ $_[0] ] if !defined $_[1];
3675 return [ $_[1] ] if !keys %{$_[0]};
3676 return [$_[0], $_[1]]
3679 return [] if !keys %{$_[0]} and !@{$_[1]};
3680 return [ $_[0] ] if !@{$_[1]};
3681 return $_[1] if !keys %{$_[0]};
3682 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3683 return [ $_[0], @{$_[1]} ];
3686 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3687 return [ $_[0] ] if !keys %{$_[1]};
3688 return [ $_[1] ] if !keys %{$_[0]};
3689 return [ $_[0] ] if $_[0] eq $_[1];
3690 return [ $_[0], $_[1] ];
3693 } => 'DBIC_RS_ATTR_MERGER');
3697 return $hm->merge ($_[1], $_[2]);
3701 sub STORABLE_freeze {
3702 my ($self, $cloning) = @_;
3703 my $to_serialize = { %$self };
3705 # A cursor in progress can't be serialized (and would make little sense anyway)
3706 delete $to_serialize->{cursor};
3708 # nor is it sensical to store a not-yet-fired-count pager
3709 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3710 delete $to_serialize->{pager};
3713 Storable::nfreeze($to_serialize);
3716 # need this hook for symmetry
3718 my ($self, $cloning, $serialized) = @_;
3720 %$self = %{ Storable::thaw($serialized) };
3726 =head2 throw_exception
3728 See L<DBIx::Class::Schema/throw_exception> for details.
3732 sub throw_exception {
3735 if (ref $self and my $rsrc = $self->result_source) {
3736 $rsrc->throw_exception(@_)
3739 DBIx::Class::Exception->throw(@_);
3743 # XXX: FIXME: Attributes docs need clearing up
3747 Attributes are used to refine a ResultSet in various ways when
3748 searching for data. They can be passed to any method which takes an
3749 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3752 Default attributes can be set on the result class using
3753 L<DBIx::Class::ResultSource/resultset_attributes>. (Please read
3754 the CAVEATS on that feature before using it!)
3756 These are in no particular order:
3762 =item Value: ( $order_by | \@order_by | \%order_by )
3766 Which column(s) to order the results by.
3768 [The full list of suitable values is documented in
3769 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3772 If a single column name, or an arrayref of names is supplied, the
3773 argument is passed through directly to SQL. The hashref syntax allows
3774 for connection-agnostic specification of ordering direction:
3776 For descending order:
3778 order_by => { -desc => [qw/col1 col2 col3/] }
3780 For explicit ascending order:
3782 order_by => { -asc => 'col' }
3784 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3785 supported, although you are strongly encouraged to use the hashref
3786 syntax as outlined above.
3792 =item Value: \@columns
3796 Shortcut to request a particular set of columns to be retrieved. Each
3797 column spec may be a string (a table column name), or a hash (in which
3798 case the key is the C<as> value, and the value is used as the C<select>
3799 expression). Adds C<me.> onto the start of any column without a C<.> in
3800 it and sets C<select> from that, then auto-populates C<as> from
3801 C<select> as normal. (You may also use the C<cols> attribute, as in
3802 earlier versions of DBIC.)
3804 Essentially C<columns> does the same as L</select> and L</as>.
3806 columns => [ 'foo', { bar => 'baz' } ]
3810 select => [qw/foo baz/],
3817 =item Value: \@columns
3821 Indicates additional columns to be selected from storage. Works the same
3822 as L</columns> but adds columns to the selection. (You may also use the
3823 C<include_columns> attribute, as in earlier versions of DBIC). For
3826 $schema->resultset('CD')->search(undef, {
3827 '+columns' => ['artist.name'],
3831 would return all CDs and include a 'name' column to the information
3832 passed to object inflation. Note that the 'artist' is the name of the
3833 column (or relationship) accessor, and 'name' is the name of the column
3834 accessor in the related table.
3836 B<NOTE:> You need to explicitly quote '+columns' when defining the attribute.
3837 Not doing so causes Perl to incorrectly interpret +columns as a bareword with a
3838 unary plus operator before it.
3840 =head2 include_columns
3844 =item Value: \@columns
3848 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3854 =item Value: \@select_columns
3858 Indicates which columns should be selected from the storage. You can use
3859 column names, or in the case of RDBMS back ends, function or stored procedure
3862 $rs = $schema->resultset('Employee')->search(undef, {
3865 { count => 'employeeid' },
3866 { max => { length => 'name' }, -as => 'longest_name' }
3871 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
3873 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
3874 use L</select>, to instruct DBIx::Class how to store the result of the column.
3875 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
3876 identifier aliasing. You can however alias a function, so you can use it in
3877 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
3878 attribute> supplied as shown in the example above.
3880 B<NOTE:> You need to explicitly quote '+select'/'+as' when defining the attributes.
3881 Not doing so causes Perl to incorrectly interpret them as a bareword with a
3882 unary plus operator before it.
3888 Indicates additional columns to be selected from storage. Works the same as
3889 L</select> but adds columns to the default selection, instead of specifying
3898 Indicates additional column names for those added via L</+select>. See L</as>.
3906 =item Value: \@inflation_names
3910 Indicates column names for object inflation. That is L</as> indicates the
3911 slot name in which the column value will be stored within the
3912 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
3913 identifier by the C<get_column> method (or via the object accessor B<if one
3914 with the same name already exists>) as shown below. The L</as> attribute has
3915 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
3917 $rs = $schema->resultset('Employee')->search(undef, {
3920 { count => 'employeeid' },
3921 { max => { length => 'name' }, -as => 'longest_name' }
3930 If the object against which the search is performed already has an accessor
3931 matching a column name specified in C<as>, the value can be retrieved using
3932 the accessor as normal:
3934 my $name = $employee->name();
3936 If on the other hand an accessor does not exist in the object, you need to
3937 use C<get_column> instead:
3939 my $employee_count = $employee->get_column('employee_count');
3941 You can create your own accessors if required - see
3942 L<DBIx::Class::Manual::Cookbook> for details.
3948 =item Value: ($rel_name | \@rel_names | \%rel_names)
3952 Contains a list of relationships that should be joined for this query. For
3955 # Get CDs by Nine Inch Nails
3956 my $rs = $schema->resultset('CD')->search(
3957 { 'artist.name' => 'Nine Inch Nails' },
3958 { join => 'artist' }
3961 Can also contain a hash reference to refer to the other relation's relations.
3964 package MyApp::Schema::Track;
3965 use base qw/DBIx::Class/;
3966 __PACKAGE__->table('track');
3967 __PACKAGE__->add_columns(qw/trackid cd position title/);
3968 __PACKAGE__->set_primary_key('trackid');
3969 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3972 # In your application
3973 my $rs = $schema->resultset('Artist')->search(
3974 { 'track.title' => 'Teardrop' },
3976 join => { cd => 'track' },
3977 order_by => 'artist.name',
3981 You need to use the relationship (not the table) name in conditions,
3982 because they are aliased as such. The current table is aliased as "me", so
3983 you need to use me.column_name in order to avoid ambiguity. For example:
3985 # Get CDs from 1984 with a 'Foo' track
3986 my $rs = $schema->resultset('CD')->search(
3989 'tracks.name' => 'Foo'
3991 { join => 'tracks' }
3994 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3995 similarly for a third time). For e.g.
3997 my $rs = $schema->resultset('Artist')->search({
3998 'cds.title' => 'Down to Earth',
3999 'cds_2.title' => 'Popular',
4001 join => [ qw/cds cds/ ],
4004 will return a set of all artists that have both a cd with title 'Down
4005 to Earth' and a cd with title 'Popular'.
4007 If you want to fetch related objects from other tables as well, see C<prefetch>
4010 NOTE: An internal join-chain pruner will discard certain joins while
4011 constructing the actual SQL query, as long as the joins in question do not
4012 affect the retrieved result. This for example includes 1:1 left joins
4013 that are not part of the restriction specification (WHERE/HAVING) nor are
4014 a part of the query selection.
4016 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4022 =item Value: ($rel_name | \@rel_names | \%rel_names)
4026 Contains one or more relationships that should be fetched along with
4027 the main query (when they are accessed afterwards the data will
4028 already be available, without extra queries to the database). This is
4029 useful for when you know you will need the related objects, because it
4030 saves at least one query:
4032 my $rs = $schema->resultset('Tag')->search(
4041 The initial search results in SQL like the following:
4043 SELECT tag.*, cd.*, artist.* FROM tag
4044 JOIN cd ON tag.cd = cd.cdid
4045 JOIN artist ON cd.artist = artist.artistid
4047 L<DBIx::Class> has no need to go back to the database when we access the
4048 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4051 Simple prefetches will be joined automatically, so there is no need
4052 for a C<join> attribute in the above search.
4054 L</prefetch> can be used with the any of the relationship types and
4055 multiple prefetches can be specified together. Below is a more complex
4056 example that prefetches a CD's artist, its liner notes (if present),
4057 the cover image, the tracks on that cd, and the guests on those
4061 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4062 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4063 My::Schema::CD->has_one( cover_image => 'My::Schema::Artwork' );
4064 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4066 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4068 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4071 my $rs = $schema->resultset('CD')->search(
4075 { artist => 'record_label'}, # belongs_to => belongs_to
4076 'liner_note', # might_have
4077 'cover_image', # has_one
4078 { tracks => 'guests' }, # has_many => has_many
4083 This will produce SQL like the following:
4085 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4089 ON artist.artistid = me.artistid
4090 JOIN record_label record_label
4091 ON record_label.labelid = artist.labelid
4092 LEFT JOIN track tracks
4093 ON tracks.cdid = me.cdid
4094 LEFT JOIN guest guests
4095 ON guests.trackid = track.trackid
4096 LEFT JOIN liner_notes liner_note
4097 ON liner_note.cdid = me.cdid
4098 JOIN cd_artwork cover_image
4099 ON cover_image.cdid = me.cdid
4102 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4103 C<tracks>, and C<guests> of the CD will all be available through the
4104 relationship accessors without the need for additional queries to the
4107 However, there is one caveat to be observed: it can be dangerous to
4108 prefetch more than one L<has_many|DBIx::Class::Relationship/has_many>
4109 relationship on a given level. e.g.:
4111 my $rs = $schema->resultset('CD')->search(
4115 'tracks', # has_many
4116 { cd_to_producer => 'producer' }, # has_many => belongs_to (i.e. m2m)
4121 The collapser currently can't identify duplicate tuples for multiple
4122 L<has_many|DBIx::Class::Relationship/has_many> relationships and as a
4123 result the second L<has_many|DBIx::Class::Relationship/has_many>
4124 relation could contain redundant objects.
4126 =head3 Using L</prefetch> with L</join>
4128 L</prefetch> implies a L</join> with the equivalent argument, and is
4129 properly merged with any existing L</join> specification. So the
4132 my $rs = $schema->resultset('CD')->search(
4133 {'record_label.name' => 'Music Product Ltd.'},
4135 join => {artist => 'record_label'},
4136 prefetch => 'artist',
4140 ... will work, searching on the record label's name, but only
4141 prefetching the C<artist>.
4143 =head3 Using L</prefetch> with L</select> / L</+select> / L</as> / L</+as>
4145 L</prefetch> implies a L</+select>/L</+as> with the fields of the
4146 prefetched relations. So given:
4148 my $rs = $schema->resultset('CD')->search(
4151 select => ['cd.title'],
4153 prefetch => 'artist',
4157 The L</select> becomes: C<'cd.title', 'artist.*'> and the L</as>
4158 becomes: C<'cd_title', 'artist.*'>.
4162 Prefetch does a lot of deep magic. As such, it may not behave exactly
4163 as you might expect.
4169 Prefetch uses the L</cache> to populate the prefetched relationships. This
4170 may or may not be what you want.
4174 If you specify a condition on a prefetched relationship, ONLY those
4175 rows that match the prefetched condition will be fetched into that relationship.
4176 This means that adding prefetch to a search() B<may alter> what is returned by
4177 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4179 my $artist_rs = $schema->resultset('Artist')->search({
4185 my $count = $artist_rs->first->cds->count;
4187 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4189 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4191 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4193 that cmp_ok() may or may not pass depending on the datasets involved. This
4194 behavior may or may not survive the 0.09 transition.
4202 =item Value: $source_alias
4206 Sets the source alias for the query. Normally, this defaults to C<me>, but
4207 nested search queries (sub-SELECTs) might need specific aliases set to
4208 reference inner queries. For example:
4211 ->related_resultset('CDs')
4212 ->related_resultset('Tracks')
4214 'track.id' => { -ident => 'none_search.id' },
4218 my $ids = $self->search({
4221 alias => 'none_search',
4222 group_by => 'none_search.id',
4223 })->get_column('id')->as_query;
4225 $self->search({ id => { -in => $ids } })
4227 This attribute is directly tied to L</current_source_alias>.
4237 Makes the resultset paged and specifies the page to retrieve. Effectively
4238 identical to creating a non-pages resultset and then calling ->page($page)
4241 If L</rows> attribute is not specified it defaults to 10 rows per page.
4243 When you have a paged resultset, L</count> will only return the number
4244 of rows in the page. To get the total, use the L</pager> and call
4245 C<total_entries> on it.
4255 Specifies the maximum number of rows for direct retrieval or the number of
4256 rows per page if the page attribute or method is used.
4262 =item Value: $offset
4266 Specifies the (zero-based) row number for the first row to be returned, or the
4267 of the first row of the first page if paging is used.
4269 =head2 software_limit
4273 =item Value: (0 | 1)
4277 When combined with L</rows> and/or L</offset> the generated SQL will not
4278 include any limit dialect stanzas. Instead the entire result will be selected
4279 as if no limits were specified, and DBIC will perform the limit locally, by
4280 artificially advancing and finishing the resulting L</cursor>.
4282 This is the recommended way of performing resultset limiting when no sane RDBMS
4283 implementation is available (e.g.
4284 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4285 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4291 =item Value: \@columns
4295 A arrayref of columns to group by. Can include columns of joined tables.
4297 group_by => [qw/ column1 column2 ... /]
4303 =item Value: $condition
4307 HAVING is a select statement attribute that is applied between GROUP BY and
4308 ORDER BY. It is applied to the after the grouping calculations have been
4311 having => { 'count_employee' => { '>=', 100 } }
4313 or with an in-place function in which case literal SQL is required:
4315 having => \[ 'count(employee) >= ?', [ count => 100 ] ]
4321 =item Value: (0 | 1)
4325 Set to 1 to group by all columns. If the resultset already has a group_by
4326 attribute, this setting is ignored and an appropriate warning is issued.
4332 Adds to the WHERE clause.
4334 # only return rows WHERE deleted IS NULL for all searches
4335 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4337 Can be overridden by passing C<< { where => undef } >> as an attribute
4340 For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
4346 Set to 1 to cache search results. This prevents extra SQL queries if you
4347 revisit rows in your ResultSet:
4349 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4351 while( my $artist = $resultset->next ) {
4355 $rs->first; # without cache, this would issue a query
4357 By default, searches are not cached.
4359 For more examples of using these attributes, see
4360 L<DBIx::Class::Manual::Cookbook>.
4366 =item Value: ( 'update' | 'shared' | \$scalar )
4370 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4371 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4374 =head1 DBIC BIND VALUES
4376 Because DBIC may need more information to bind values than just the column name
4377 and value itself, it uses a special format for both passing and receiving bind
4378 values. Each bind value should be composed of an arrayref of
4379 C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
4385 If present (in any form), this is what is being passed directly to bind_param.
4386 Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
4387 a single numerical type, while DBD::Pg takes a hashref if bind options.)
4389 If this is specified, all other bind options described below are ignored.
4393 If present, this is used to infer the actual bind attribute by passing to
4394 C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
4395 "data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
4397 Note that the data type is somewhat freeform (hence the sqlt_ prefix);
4398 currently drivers are expected to "Do the Right Thing" when given a common
4399 datatype name. (Not ideal, but that's what we got at this point.)
4403 Currently used to correctly allocate buffers for bind_param_inout().
4404 Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
4405 or to a sensible value based on the "data_type".
4409 Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
4410 explicitly specified they are never overriden). Also used by some weird DBDs,
4411 where the column name should be available at bind_param time (e.g. Oracle).
4415 For backwards compatibility and convenience, the following shortcuts are
4418 [ $name => $val ] === [ { dbic_colname => $name }, $val ]
4419 [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
4420 [ undef, $val ] === [ {}, $val ]
4422 =head1 AUTHOR AND CONTRIBUTORS
4424 See L<AUTHOR|DBIx::Class/AUTHOR> and L<CONTRIBUTORS|DBIx::Class/CONTRIBUTORS> in DBIx::Class
4428 You may distribute this code under the same terms as Perl itself.