1 package DBIx::Class::ResultSet;
5 use base qw/DBIx::Class/;
7 use DBIx::Class::ResultSetColumn;
8 use Scalar::Util qw/blessed weaken reftype/;
9 use DBIx::Class::_Util 'fail_on_internal_wantarray';
11 use Data::Compare (); # no imports!!! guard against insane architecture
13 # not importing first() as it will clash with our own method
17 # De-duplication in _merge_attr() is disabled, but left in for reference
18 # (the merger is used for other things that ought not to be de-duped)
19 *__HM_DEDUP = sub () { 0 };
29 # this is real - CDBICompat overrides it with insanity
30 # yes, prototype won't matter, but that's for now ;)
33 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class result_source/);
37 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
41 my $users_rs = $schema->resultset('User');
42 while( $user = $users_rs->next) {
43 print $user->username;
46 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
47 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
51 A ResultSet is an object which stores a set of conditions representing
52 a query. It is the backbone of DBIx::Class (i.e. the really
53 important/useful bit).
55 No SQL is executed on the database when a ResultSet is created, it
56 just stores all the conditions needed to create the query.
58 A basic ResultSet representing the data of an entire table is returned
59 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
60 L<Source|DBIx::Class::Manual::Glossary/Source> name.
62 my $users_rs = $schema->resultset('User');
64 A new ResultSet is returned from calling L</search> on an existing
65 ResultSet. The new one will contain all the conditions of the
66 original, plus any new conditions added in the C<search> call.
68 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
69 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
72 The query that the ResultSet represents is B<only> executed against
73 the database when these methods are called:
74 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
76 If a resultset is used in a numeric context it returns the L</count>.
77 However, if it is used in a boolean context it is B<always> true. So if
78 you want to check if a resultset has any results, you must use C<if $rs
81 =head1 CUSTOM ResultSet CLASSES THAT USE Moose
83 If you want to make your custom ResultSet classes with L<Moose>, use a template
86 package MyApp::Schema::ResultSet::User;
89 use namespace::autoclean;
91 extends 'DBIx::Class::ResultSet';
93 sub BUILDARGS { $_[2] }
97 __PACKAGE__->meta->make_immutable;
101 The L<MooseX::NonMoose> is necessary so that the L<Moose> constructor does not
102 clash with the regular ResultSet constructor. Alternatively, you can use:
104 __PACKAGE__->meta->make_immutable(inline_constructor => 0);
106 The L<BUILDARGS|Moose::Manual::Construction/BUILDARGS> is necessary because the
107 signature of the ResultSet C<new> is C<< ->new($source, \%args) >>.
111 =head2 Chaining resultsets
113 Let's say you've got a query that needs to be run to return some data
114 to the user. But, you have an authorization system in place that
115 prevents certain users from seeing certain information. So, you want
116 to construct the basic query in one method, but add constraints to it in
121 my $request = $self->get_request; # Get a request object somehow.
122 my $schema = $self->result_source->schema;
124 my $cd_rs = $schema->resultset('CD')->search({
125 title => $request->param('title'),
126 year => $request->param('year'),
129 $cd_rs = $self->apply_security_policy( $cd_rs );
131 return $cd_rs->all();
134 sub apply_security_policy {
143 =head3 Resolving conditions and attributes
145 When a resultset is chained from another resultset (e.g.:
146 C<< my $new_rs = $old_rs->search(\%extra_cond, \%attrs) >>), conditions
147 and attributes with the same keys need resolving.
149 If any of L</columns>, L</select>, L</as> are present, they reset the
150 original selection, and start the selection "clean".
152 The L</join>, L</prefetch>, L</+columns>, L</+select>, L</+as> attributes
153 are merged into the existing ones from the original resultset.
155 The L</where> and L</having> attributes, and any search conditions, are
156 merged with an SQL C<AND> to the existing condition from the original
159 All other attributes are overridden by any new ones supplied in the
162 =head2 Multiple queries
164 Since a resultset just defines a query, you can do all sorts of
165 things with it with the same object.
167 # Don't hit the DB yet.
168 my $cd_rs = $schema->resultset('CD')->search({
169 title => 'something',
173 # Each of these hits the DB individually.
174 my $count = $cd_rs->count;
175 my $most_recent = $cd_rs->get_column('date_released')->max();
176 my @records = $cd_rs->all;
178 And it's not just limited to SELECT statements.
184 $cd_rs->create({ artist => 'Fred' });
186 Which is the same as:
188 $schema->resultset('CD')->create({
189 title => 'something',
194 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
202 =item Arguments: L<$source|DBIx::Class::ResultSource>, L<\%attrs?|/ATTRIBUTES>
204 =item Return Value: L<$resultset|/search>
208 The resultset constructor. Takes a source object (usually a
209 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
210 L</ATTRIBUTES> below). Does not perform any queries -- these are
211 executed as needed by the other methods.
213 Generally you never construct a resultset manually. Instead you get one
215 C<< $schema->L<resultset|DBIx::Class::Schema/resultset>('$source_name') >>
216 or C<< $another_resultset->L<search|/search>(...) >> (the later called in
219 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
225 If called on an object, proxies to L</new_result> instead, so
227 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
229 will return a CD object, not a ResultSet, and is equivalent to:
231 my $cd = $schema->resultset('CD')->new_result({ title => 'Spoon' });
233 Please also keep in mind that many internals call L</new_result> directly,
234 so overloading this method with the idea of intercepting new result object
235 creation B<will not work>. See also warning pertaining to L</create>.
243 return $class->new_result(@_) if ref $class;
245 my ($source, $attrs) = @_;
246 $source = $source->resolve
247 if $source->isa('DBIx::Class::ResultSourceHandle');
249 $attrs = { %{$attrs||{}} };
250 delete @{$attrs}{qw(_last_sqlmaker_alias_map _related_results_construction)};
252 if ($attrs->{page}) {
253 $attrs->{rows} ||= 10;
256 $attrs->{alias} ||= 'me';
259 result_source => $source,
260 cond => $attrs->{where},
265 # if there is a dark selector, this means we are already in a
266 # chain and the cleanup/sanification was taken care of by
268 $self->_normalize_selection($attrs)
269 unless $attrs->{_dark_selector};
272 $attrs->{result_class} || $source->result_class
282 =item Arguments: L<$cond|DBIx::Class::SQLMaker> | undef, L<\%attrs?|/ATTRIBUTES>
284 =item Return Value: $resultset (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
288 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
289 my $new_rs = $cd_rs->search({ year => 2005 });
291 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
292 # year = 2005 OR year = 2004
294 In list context, C<< ->all() >> is called implicitly on the resultset, thus
295 returning a list of L<result|DBIx::Class::Manual::ResultClass> objects instead.
296 To avoid that, use L</search_rs>.
298 If you need to pass in additional attributes but no additional condition,
299 call it as C<search(undef, \%attrs)>.
301 # "SELECT name, artistid FROM $artist_table"
302 my @all_artists = $schema->resultset('Artist')->search(undef, {
303 columns => [qw/name artistid/],
306 For a list of attributes that can be passed to C<search>, see
307 L</ATTRIBUTES>. For more examples of using this function, see
308 L<Searching|DBIx::Class::Manual::Cookbook/SEARCHING>. For a complete
309 documentation for the first argument, see L<SQL::Abstract/"WHERE CLAUSES">
310 and its extension L<DBIx::Class::SQLMaker>.
312 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
316 Note that L</search> does not process/deflate any of the values passed in the
317 L<SQL::Abstract>-compatible search condition structure. This is unlike other
318 condition-bound methods L</new_result>, L</create> and L</find>. The user must ensure
319 manually that any value passed to this method will stringify to something the
320 RDBMS knows how to deal with. A notable example is the handling of L<DateTime>
321 objects, for more info see:
322 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
328 my $rs = $self->search_rs( @_ );
331 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_WANTARRAY and my $sog = fail_on_internal_wantarray($rs);
334 elsif (defined wantarray) {
338 # we can be called by a relationship helper, which in
339 # turn may be called in void context due to some braindead
340 # overload or whatever else the user decided to be clever
341 # at this particular day. Thus limit the exception to
342 # external code calls only
343 $self->throw_exception ('->search is *not* a mutator, calling it in void context makes no sense')
344 if (caller)[0] !~ /^\QDBIx::Class::/;
354 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
356 =item Return Value: L<$resultset|/search>
360 This method does the same exact thing as search() except it will
361 always return a resultset, even in list context.
368 my $rsrc = $self->result_source;
369 my ($call_cond, $call_attrs);
371 # Special-case handling for (undef, undef) or (undef)
372 # Note that (foo => undef) is valid deprecated syntax
373 @_ = () if not scalar grep { defined $_ } @_;
379 # fish out attrs in the ($condref, $attr) case
380 elsif (@_ == 2 and ( ! defined $_[0] or (ref $_[0]) ne '') ) {
381 ($call_cond, $call_attrs) = @_;
384 $self->throw_exception('Odd number of arguments to search')
388 carp_unique 'search( %condition ) is deprecated, use search( \%condition ) instead'
389 unless $rsrc->result_class->isa('DBIx::Class::CDBICompat');
391 for my $i (0 .. $#_) {
393 $self->throw_exception ('All keys in condition key/value pairs must be plain scalars')
394 if (! defined $_[$i] or ref $_[$i] ne '');
400 # see if we can keep the cache (no $rs changes)
402 my %safe = (alias => 1, cache => 1);
403 if ( ! List::Util::first { !$safe{$_} } keys %$call_attrs and (
406 ref $call_cond eq 'HASH' && ! keys %$call_cond
408 ref $call_cond eq 'ARRAY' && ! @$call_cond
410 $cache = $self->get_cache;
413 my $old_attrs = { %{$self->{attrs}} };
414 my ($old_having, $old_where) = delete @{$old_attrs}{qw(having where)};
416 my $new_attrs = { %$old_attrs };
418 # take care of call attrs (only if anything is changing)
419 if ($call_attrs and keys %$call_attrs) {
421 # copy for _normalize_selection
422 $call_attrs = { %$call_attrs };
424 my @selector_attrs = qw/select as columns cols +select +as +columns include_columns/;
426 # reset the current selector list if new selectors are supplied
427 if (List::Util::first { exists $call_attrs->{$_} } qw/columns cols select as/) {
428 delete @{$old_attrs}{(@selector_attrs, '_dark_selector')};
431 # Normalize the new selector list (operates on the passed-in attr structure)
432 # Need to do it on every chain instead of only once on _resolved_attrs, in
433 # order to allow detection of empty vs partial 'as'
434 $call_attrs->{_dark_selector} = $old_attrs->{_dark_selector}
435 if $old_attrs->{_dark_selector};
436 $self->_normalize_selection ($call_attrs);
438 # start with blind overwriting merge, exclude selector attrs
439 $new_attrs = { %{$old_attrs}, %{$call_attrs} };
440 delete @{$new_attrs}{@selector_attrs};
442 for (@selector_attrs) {
443 $new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
444 if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
447 # older deprecated name, use only if {columns} is not there
448 if (my $c = delete $new_attrs->{cols}) {
449 carp_unique( "Resultset attribute 'cols' is deprecated, use 'columns' instead" );
450 if ($new_attrs->{columns}) {
451 carp "Resultset specifies both the 'columns' and the legacy 'cols' attributes - ignoring 'cols'";
454 $new_attrs->{columns} = $c;
459 # join/prefetch use their own crazy merging heuristics
460 foreach my $key (qw/join prefetch/) {
461 $new_attrs->{$key} = $self->_merge_joinpref_attr($old_attrs->{$key}, $call_attrs->{$key})
462 if exists $call_attrs->{$key};
465 # stack binds together
466 $new_attrs->{bind} = [ @{ $old_attrs->{bind} || [] }, @{ $call_attrs->{bind} || [] } ];
470 for ($old_where, $call_cond) {
472 $new_attrs->{where} = $self->_stack_cond (
473 $_, $new_attrs->{where}
478 if (defined $old_having) {
479 $new_attrs->{having} = $self->_stack_cond (
480 $old_having, $new_attrs->{having}
484 my $rs = (ref $self)->new($rsrc, $new_attrs);
486 $rs->set_cache($cache) if ($cache);
492 sub _normalize_selection {
493 my ($self, $attrs) = @_;
496 if ( exists $attrs->{include_columns} ) {
497 carp_unique( "Resultset attribute 'include_columns' is deprecated, use '+columns' instead" );
498 $attrs->{'+columns'} = $self->_merge_attr(
499 $attrs->{'+columns'}, delete $attrs->{include_columns}
503 # columns are always placed first, however
505 # Keep the X vs +X separation until _resolved_attrs time - this allows to
506 # delay the decision on whether to use a default select list ($rsrc->columns)
507 # allowing stuff like the remove_columns helper to work
509 # select/as +select/+as pairs need special handling - the amount of select/as
510 # elements in each pair does *not* have to be equal (think multicolumn
511 # selectors like distinct(foo, bar) ). If the selector is bare (no 'as'
512 # supplied at all) - try to infer the alias, either from the -as parameter
513 # of the selector spec, or use the parameter whole if it looks like a column
514 # name (ugly legacy heuristic). If all fails - leave the selector bare (which
515 # is ok as well), but make sure no more additions to the 'as' chain take place
516 for my $pref ('', '+') {
518 my ($sel, $as) = map {
519 my $key = "${pref}${_}";
521 my $val = [ ref $attrs->{$key} eq 'ARRAY'
523 : $attrs->{$key} || ()
525 delete $attrs->{$key};
529 if (! @$as and ! @$sel ) {
532 elsif (@$as and ! @$sel) {
533 $self->throw_exception(
534 "Unable to handle ${pref}as specification (@$as) without a corresponding ${pref}select"
538 # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
539 # if any @$as has been supplied we assume the user knows what (s)he is doing
540 # and blindly keep stacking up pieces
541 unless ($attrs->{_dark_selector}) {
544 if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
545 push @$as, $_->{-as};
547 # assume any plain no-space, no-parenthesis string to be a column spec
548 # FIXME - this is retarded but is necessary to support shit like 'count(foo)'
549 elsif ( ! ref $_ and $_ =~ /^ [^\s\(\)]+ $/x) {
552 # if all else fails - raise a flag that no more aliasing will be allowed
554 $attrs->{_dark_selector} = {
556 string => ($dark_sel_dumper ||= do {
557 require Data::Dumper::Concise;
558 Data::Dumper::Concise::DumperObject()->Indent(0);
559 })->Values([$_])->Dump
567 elsif (@$as < @$sel) {
568 $self->throw_exception(
569 "Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
572 elsif ($pref and $attrs->{_dark_selector}) {
573 $self->throw_exception(
574 "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
580 $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
581 $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
586 my ($self, $left, $right) = @_;
588 # collapse single element top-level conditions
589 # (single pass only, unlikely to need recursion)
590 for ($left, $right) {
591 if (ref $_ eq 'ARRAY') {
599 elsif (ref $_ eq 'HASH') {
600 my ($first, $more) = keys %$_;
603 if (! defined $first) {
607 elsif (! defined $more) {
608 if ($first eq '-and' and ref $_->{'-and'} eq 'HASH') {
611 elsif ($first eq '-or' and ref $_->{'-or'} eq 'ARRAY') {
618 # merge hashes with weeding out of duplicates (simple cases only)
619 if (ref $left eq 'HASH' and ref $right eq 'HASH') {
621 # shallow copy to destroy
622 $right = { %$right };
623 for (grep { exists $right->{$_} } keys %$left) {
624 # the use of eq_deeply here is justified - the rhs of an
625 # expression can contain a lot of twisted weird stuff
626 delete $right->{$_} if Data::Compare::Compare( $left->{$_}, $right->{$_} );
629 $right = undef unless keys %$right;
633 if (defined $left xor defined $right) {
634 return defined $left ? $left : $right;
636 elsif (! defined $left) {
640 return { -and => [ $left, $right ] };
644 =head2 search_literal
646 B<CAVEAT>: C<search_literal> is provided for Class::DBI compatibility and
647 should only be used in that context. C<search_literal> is a convenience
648 method. It is equivalent to calling C<< $schema->search(\[]) >>, but if you
649 want to ensure columns are bound correctly, use L</search>.
651 See L<DBIx::Class::Manual::Cookbook/SEARCHING> and
652 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
653 require C<search_literal>.
657 =item Arguments: $sql_fragment, @standalone_bind_values
659 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
663 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
664 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
666 Pass a literal chunk of SQL to be added to the conditional part of the
669 Example of how to use C<search> instead of C<search_literal>
671 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
672 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
677 my ($self, $sql, @bind) = @_;
679 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
682 return $self->search(\[ $sql, map [ {} => $_ ], @bind ], ($attr || () ));
689 =item Arguments: \%columns_values | @pk_values, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
691 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
695 Finds and returns a single row based on supplied criteria. Takes either a
696 hashref with the same format as L</create> (including inference of foreign
697 keys from related objects), or a list of primary key values in the same
698 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
699 declaration on the L</result_source>.
701 In either case an attempt is made to combine conditions already existing on
702 the resultset with the condition passed to this method.
704 To aid with preparing the correct query for the storage you may supply the
705 C<key> attribute, which is the name of a
706 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
707 unique constraint corresponding to the
708 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
709 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
710 to construct a query that satisfies the named unique constraint fully (
711 non-NULL values for each column member of the constraint) an exception is
714 If no C<key> is specified, the search is carried over all unique constraints
715 which are fully defined by the available condition.
717 If no such constraint is found, C<find> currently defaults to a simple
718 C<< search->(\%column_values) >> which may or may not do what you expect.
719 Note that this fallback behavior may be deprecated in further versions. If
720 you need to search with arbitrary conditions - use L</search>. If the query
721 resulting from this fallback produces more than one row, a warning to the
722 effect is issued, though only the first row is constructed and returned as
725 In addition to C<key>, L</find> recognizes and applies standard
726 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
728 Note that if you have extra concerns about the correctness of the resulting
729 query you need to specify the C<key> attribute and supply the entire condition
730 as an argument to find (since it is not always possible to perform the
731 combination of the resultset condition with the supplied one, especially if
732 the resultset condition contains literal sql).
734 For example, to find a row by its primary key:
736 my $cd = $schema->resultset('CD')->find(5);
738 You can also find a row by a specific unique constraint:
740 my $cd = $schema->resultset('CD')->find(
742 artist => 'Massive Attack',
743 title => 'Mezzanine',
745 { key => 'cd_artist_title' }
748 See also L</find_or_create> and L</update_or_create>.
754 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
756 my $rsrc = $self->result_source;
759 if (exists $attrs->{key}) {
760 $constraint_name = defined $attrs->{key}
762 : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
766 # Parse out the condition from input
769 if (ref $_[0] eq 'HASH') {
770 $call_cond = { %{$_[0]} };
773 # if only values are supplied we need to default to 'primary'
774 $constraint_name = 'primary' unless defined $constraint_name;
776 my @c_cols = $rsrc->unique_constraint_columns($constraint_name);
778 $self->throw_exception(
779 "No constraint columns, maybe a malformed '$constraint_name' constraint?"
782 $self->throw_exception (
783 'find() expects either a column/value hashref, or a list of values '
784 . "corresponding to the columns of the specified unique constraint '$constraint_name'"
785 ) unless @c_cols == @_;
788 @{$call_cond}{@c_cols} = @_;
792 for my $key (keys %$call_cond) {
794 my $keyref = ref($call_cond->{$key})
796 my $relinfo = $rsrc->relationship_info($key)
798 my $val = delete $call_cond->{$key};
800 next if $keyref eq 'ARRAY'; # has_many for multi_create
802 my $rel_q = $rsrc->_resolve_condition(
803 $relinfo->{cond}, $val, $key, $key
805 die "Can't handle complex relationship conditions in find" if ref($rel_q) ne 'HASH';
806 @related{keys %$rel_q} = values %$rel_q;
810 # relationship conditions take precedence (?)
811 @{$call_cond}{keys %related} = values %related;
813 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
815 if (defined $constraint_name) {
816 $final_cond = $self->_qualify_cond_columns (
818 $self->_build_unique_cond (
826 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
827 # This means that we got here after a merger of relationship conditions
828 # in ::Relationship::Base::search_related (the row method), and furthermore
829 # the relationship is of the 'single' type. This means that the condition
830 # provided by the relationship (already attached to $self) is sufficient,
831 # as there can be only one row in the database that would satisfy the
835 # no key was specified - fall down to heuristics mode:
836 # run through all unique queries registered on the resultset, and
837 # 'OR' all qualifying queries together
838 my (@unique_queries, %seen_column_combinations);
839 for my $c_name ($rsrc->unique_constraint_names) {
840 next if $seen_column_combinations{
841 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
844 push @unique_queries, try {
845 $self->_build_unique_cond ($c_name, $call_cond, 'croak_on_nulls')
849 $final_cond = @unique_queries
850 ? [ map { $self->_qualify_cond_columns($_, $alias) } @unique_queries ]
851 : $self->_non_unique_find_fallback ($call_cond, $attrs)
855 # Run the query, passing the result_class since it should propagate for find
856 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
857 if ($rs->_resolved_attrs->{collapse}) {
859 carp "Query returned more than one row" if $rs->next;
867 # This is a stop-gap method as agreed during the discussion on find() cleanup:
868 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
870 # It is invoked when find() is called in legacy-mode with insufficiently-unique
871 # condition. It is provided for overrides until a saner way forward is devised
873 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
874 # the road. Please adjust your tests accordingly to catch this situation early
875 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
877 # The method will not be removed without an adequately complete replacement
878 # for strict-mode enforcement
879 sub _non_unique_find_fallback {
880 my ($self, $cond, $attrs) = @_;
882 return $self->_qualify_cond_columns(
884 exists $attrs->{alias}
886 : $self->{attrs}{alias}
891 sub _qualify_cond_columns {
892 my ($self, $cond, $alias) = @_;
894 my %aliased = %$cond;
895 for (keys %aliased) {
896 $aliased{"$alias.$_"} = delete $aliased{$_}
903 sub _build_unique_cond {
904 my ($self, $constraint_name, $extra_cond, $croak_on_null) = @_;
906 my @c_cols = $self->result_source->unique_constraint_columns($constraint_name);
908 # combination may fail if $self->{cond} is non-trivial
909 my ($final_cond) = try {
910 $self->_merge_with_rscond ($extra_cond)
915 # trim out everything not in $columns
916 $final_cond = { map {
917 exists $final_cond->{$_}
918 ? ( $_ => $final_cond->{$_} )
922 if (my @missing = grep
923 { ! ($croak_on_null ? defined $final_cond->{$_} : exists $final_cond->{$_}) }
926 $self->throw_exception( sprintf ( "Unable to satisfy requested constraint '%s', no values for column(s): %s",
928 join (', ', map { "'$_'" } @missing),
935 !$ENV{DBIC_NULLABLE_KEY_NOWARN}
937 my @undefs = sort grep { ! defined $final_cond->{$_} } (keys %$final_cond)
939 carp_unique ( sprintf (
940 "NULL/undef values supplied for requested unique constraint '%s' (NULL "
941 . 'values in column(s): %s). This is almost certainly not what you wanted, '
942 . 'though you can set DBIC_NULLABLE_KEY_NOWARN to disable this warning.',
944 join (', ', map { "'$_'" } @undefs),
951 =head2 search_related
955 =item Arguments: $rel_name, $cond?, L<\%attrs?|/ATTRIBUTES>
957 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
961 $new_rs = $cd_rs->search_related('artist', {
965 Searches the specified relationship, optionally specifying a condition and
966 attributes for matching records. See L</ATTRIBUTES> for more information.
968 In list context, C<< ->all() >> is called implicitly on the resultset, thus
969 returning a list of result objects instead. To avoid that, use L</search_related_rs>.
971 See also L</search_related_rs>.
976 return shift->related_resultset(shift)->search(@_);
979 =head2 search_related_rs
981 This method works exactly the same as search_related, except that
982 it guarantees a resultset, even in list context.
986 sub search_related_rs {
987 return shift->related_resultset(shift)->search_rs(@_);
994 =item Arguments: none
996 =item Return Value: L<$cursor|DBIx::Class::Cursor>
1000 Returns a storage-driven cursor to the given resultset. See
1001 L<DBIx::Class::Cursor> for more information.
1008 return $self->{cursor} ||= do {
1009 my $attrs = $self->_resolved_attrs;
1010 $self->result_source->storage->select(
1011 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
1020 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1022 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1026 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1028 Inflates the first result without creating a cursor if the resultset has
1029 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1032 While this method can take an optional search condition (just like L</search>)
1033 being a fast-code-path it does not recognize search attributes. If you need to
1034 add extra joins or similar, call L</search> and then chain-call L</single> on the
1035 L<DBIx::Class::ResultSet> returned.
1041 As of 0.08100, this method enforces the assumption that the preceding
1042 query returns only one row. If more than one row is returned, you will receive
1045 Query returned more than one row
1047 In this case, you should be using L</next> or L</find> instead, or if you really
1048 know what you are doing, use the L</rows> attribute to explicitly limit the size
1051 This method will also throw an exception if it is called on a resultset prefetching
1052 has_many, as such a prefetch implies fetching multiple rows from the database in
1053 order to assemble the resulting object.
1060 my ($self, $where) = @_;
1062 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1065 my $attrs = { %{$self->_resolved_attrs} };
1067 $self->throw_exception(
1068 'single() can not be used on resultsets collapsing a has_many. Use find( \%cond ) or next() instead'
1069 ) if $attrs->{collapse};
1072 if (defined $attrs->{where}) {
1075 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1076 $where, delete $attrs->{where} ]
1079 $attrs->{where} = $where;
1083 my $data = [ $self->result_source->storage->select_single(
1084 $attrs->{from}, $attrs->{select},
1085 $attrs->{where}, $attrs
1088 return undef unless @$data;
1089 $self->{_stashed_rows} = [ $data ];
1090 $self->_construct_results->[0];
1097 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1099 =item Return Value: L<$resultsetcolumn|DBIx::Class::ResultSetColumn>
1103 my $max_length = $rs->get_column('length')->max;
1105 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1110 my ($self, $column) = @_;
1111 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
1119 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1121 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1125 # WHERE title LIKE '%blue%'
1126 $cd_rs = $rs->search_like({ title => '%blue%'});
1128 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1129 that this is simply a convenience method retained for ex Class::DBI users.
1130 You most likely want to use L</search> with specific operators.
1132 For more information, see L<DBIx::Class::Manual::Cookbook>.
1134 This method is deprecated and will be removed in 0.09. Use L</search()>
1135 instead. An example conversion is:
1137 ->search_like({ foo => 'bar' });
1141 ->search({ foo => { like => 'bar' } });
1148 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1149 .' Instead use ->search({ x => { -like => "y%" } })'
1150 .' (note the outer pair of {}s - they are important!)'
1152 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1153 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1154 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1155 return $class->search($query, { %$attrs });
1162 =item Arguments: $first, $last
1164 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1168 Returns a resultset or object list representing a subset of elements from the
1169 resultset slice is called on. Indexes are from 0, i.e., to get the first
1170 three records, call:
1172 my ($one, $two, $three) = $rs->slice(0, 2);
1177 my ($self, $min, $max) = @_;
1178 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1179 $attrs->{offset} = $self->{attrs}{offset} || 0;
1180 $attrs->{offset} += $min;
1181 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1182 return $self->search(undef, $attrs);
1189 =item Arguments: none
1191 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1195 Returns the next element in the resultset (C<undef> is there is none).
1197 Can be used to efficiently iterate over records in the resultset:
1199 my $rs = $schema->resultset('CD')->search;
1200 while (my $cd = $rs->next) {
1204 Note that you need to store the resultset object, and call C<next> on it.
1205 Calling C<< resultset('Table')->next >> repeatedly will always return the
1206 first record from the resultset.
1213 if (my $cache = $self->get_cache) {
1214 $self->{all_cache_position} ||= 0;
1215 return $cache->[$self->{all_cache_position}++];
1218 if ($self->{attrs}{cache}) {
1219 delete $self->{pager};
1220 $self->{all_cache_position} = 1;
1221 return ($self->all)[0];
1224 return shift(@{$self->{_stashed_results}}) if @{ $self->{_stashed_results}||[] };
1226 $self->{_stashed_results} = $self->_construct_results
1229 return shift @{$self->{_stashed_results}};
1232 # Constructs as many results as it can in one pass while respecting
1233 # cursor laziness. Several modes of operation:
1235 # * Always builds everything present in @{$self->{_stashed_rows}}
1236 # * If called with $fetch_all true - pulls everything off the cursor and
1237 # builds all result structures (or objects) in one pass
1238 # * If $self->_resolved_attrs->{collapse} is true, checks the order_by
1239 # and if the resultset is ordered properly by the left side:
1240 # * Fetches stuff off the cursor until the "master object" changes,
1241 # and saves the last extra row (if any) in @{$self->{_stashed_rows}}
1243 # * Just fetches, and collapses/constructs everything as if $fetch_all
1244 # was requested (there is no other way to collapse except for an
1246 # * If no collapse is requested - just get the next row, construct and
1248 sub _construct_results {
1249 my ($self, $fetch_all) = @_;
1251 my $rsrc = $self->result_source;
1252 my $attrs = $self->_resolved_attrs;
1257 ! $attrs->{order_by}
1261 my @pcols = $rsrc->primary_columns
1263 # default order for collapsing unless the user asked for something
1264 $attrs->{order_by} = [ map { join '.', $attrs->{alias}, $_} @pcols ];
1265 $attrs->{_ordered_for_collapse} = 1;
1266 $attrs->{_order_is_artificial} = 1;
1269 # this will be used as both initial raw-row collector AND as a RV of
1270 # _construct_results. Not regrowing the array twice matters a lot...
1271 # a surprising amount actually
1272 my $rows = delete $self->{_stashed_rows};
1274 my $cursor; # we may not need one at all
1276 my $did_fetch_all = $fetch_all;
1279 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1280 $rows = [ ($rows ? @$rows : ()), $self->cursor->all ];
1282 elsif( $attrs->{collapse} ) {
1284 # a cursor will need to be closed over in case of collapse
1285 $cursor = $self->cursor;
1287 $attrs->{_ordered_for_collapse} = (
1293 ->_main_source_order_by_portion_is_stable($rsrc, $attrs->{order_by}, $attrs->{where})
1295 ) unless defined $attrs->{_ordered_for_collapse};
1297 if (! $attrs->{_ordered_for_collapse}) {
1300 # instead of looping over ->next, use ->all in stealth mode
1301 # *without* calling a ->reset afterwards
1302 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1303 if (! $cursor->{_done}) {
1304 $rows = [ ($rows ? @$rows : ()), $cursor->all ];
1305 $cursor->{_done} = 1;
1310 if (! $did_fetch_all and ! @{$rows||[]} ) {
1311 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1312 $cursor ||= $self->cursor;
1313 if (scalar (my @r = $cursor->next) ) {
1318 return undef unless @{$rows||[]};
1320 # sanity check - people are too clever for their own good
1321 if ($attrs->{collapse} and my $aliastypes = $attrs->{_last_sqlmaker_alias_map} ) {
1323 my $multiplied_selectors;
1324 for my $sel_alias ( grep { $_ ne $attrs->{alias} } keys %{ $aliastypes->{selecting} } ) {
1326 $aliastypes->{multiplying}{$sel_alias}
1328 $aliastypes->{premultiplied}{$sel_alias}
1330 $multiplied_selectors->{$_} = 1 for values %{$aliastypes->{selecting}{$sel_alias}{-seen_columns}}
1334 for my $i (0 .. $#{$attrs->{as}} ) {
1335 my $sel = $attrs->{select}[$i];
1337 if (ref $sel eq 'SCALAR') {
1340 elsif( ref $sel eq 'REF' and ref $$sel eq 'ARRAY' ) {
1344 $self->throw_exception(
1345 'Result collapse not possible - selection from a has_many source redirected to the main object'
1346 ) if ($multiplied_selectors->{$sel} and $attrs->{as}[$i] !~ /\./);
1350 # hotspot - skip the setter
1351 my $res_class = $self->_result_class;
1353 my $inflator_cref = $self->{_result_inflator}{cref} ||= do {
1354 $res_class->can ('inflate_result')
1355 or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
1358 my $infmap = $attrs->{as};
1360 $self->{_result_inflator}{is_core_row} = ( (
1363 ( \&DBIx::Class::Row::inflate_result || die "No ::Row::inflate_result() - can't happen" )
1364 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_core_row};
1366 $self->{_result_inflator}{is_hri} = ( (
1367 ! $self->{_result_inflator}{is_core_row}
1370 require DBIx::Class::ResultClass::HashRefInflator
1372 DBIx::Class::ResultClass::HashRefInflator->can('inflate_result')
1374 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_hri};
1377 if (! $attrs->{_related_results_construction}) {
1378 # construct a much simpler array->hash folder for the one-table cases right here
1379 if ($self->{_result_inflator}{is_hri}) {
1380 for my $r (@$rows) {
1381 $r = { map { $infmap->[$_] => $r->[$_] } 0..$#$infmap };
1384 # FIXME SUBOPTIMAL this is a very very very hot spot
1385 # while rather optimal we can *still* do much better, by
1386 # building a smarter Row::inflate_result(), and
1387 # switch to feeding it data via a much leaner interface
1389 # crude unscientific benchmarking indicated the shortcut eval is not worth it for
1390 # this particular resultset size
1391 elsif (@$rows < 60) {
1392 for my $r (@$rows) {
1393 $r = $inflator_cref->($res_class, $rsrc, { map { $infmap->[$_] => $r->[$_] } (0..$#$infmap) } );
1398 '$_ = $inflator_cref->($res_class, $rsrc, { %s }) for @$rows',
1399 join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap )
1405 $self->{_result_inflator}{is_hri} ? 'hri'
1406 : $self->{_result_inflator}{is_core_row} ? 'classic_pruning'
1407 : 'classic_nonpruning'
1410 # $args and $attrs to _mk_row_parser are separated to delineate what is
1411 # core collapser stuff and what is dbic $rs specific
1412 @{$self->{_row_parser}{$parser_type}}{qw(cref nullcheck)} = $rsrc->_mk_row_parser({
1414 inflate_map => $infmap,
1415 collapse => $attrs->{collapse},
1416 premultiplied => $attrs->{_main_source_premultiplied},
1417 hri_style => $self->{_result_inflator}{is_hri},
1418 prune_null_branches => $self->{_result_inflator}{is_hri} || $self->{_result_inflator}{is_core_row},
1419 }, $attrs) unless $self->{_row_parser}{$parser_type}{cref};
1421 # column_info metadata historically hasn't been too reliable.
1422 # We need to start fixing this somehow (the collapse resolver
1423 # can't work without it). Add an explicit check for the *main*
1424 # result, hopefully this will gradually weed out such errors
1426 # FIXME - this is a temporary kludge that reduces performance
1427 # It is however necessary for the time being
1428 my ($unrolled_non_null_cols_to_check, $err);
1430 if (my $check_non_null_cols = $self->{_row_parser}{$parser_type}{nullcheck} ) {
1433 'Collapse aborted due to invalid ResultSource metadata - the following '
1434 . 'selections are declared non-nullable but NULLs were retrieved: '
1438 COL: for my $i (@$check_non_null_cols) {
1439 ! defined $_->[$i] and push @violating_idx, $i and next COL for @$rows;
1442 $self->throw_exception( $err . join (', ', map { "'$infmap->[$_]'" } @violating_idx ) )
1445 $unrolled_non_null_cols_to_check = join (',', @$check_non_null_cols);
1449 ($did_fetch_all or ! $attrs->{collapse}) ? undef
1450 : defined $unrolled_non_null_cols_to_check ? eval sprintf <<'EOS', $unrolled_non_null_cols_to_check
1452 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1453 my @r = $cursor->next or return;
1454 if (my @violating_idx = grep { ! defined $r[$_] } (%s) ) {
1455 $self->throw_exception( $err . join (', ', map { "'$infmap->[$_]'" } @violating_idx ) )
1461 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1462 my @r = $cursor->next or return;
1467 $self->{_row_parser}{$parser_type}{cref}->(
1469 $next_cref ? ( $next_cref, $self->{_stashed_rows} = [] ) : (),
1472 # Special-case multi-object HRI - there is no $inflator_cref pass
1473 unless ($self->{_result_inflator}{is_hri}) {
1474 $_ = $inflator_cref->($res_class, $rsrc, @$_) for @$rows
1478 # The @$rows check seems odd at first - why wouldn't we want to warn
1479 # regardless? The issue is things like find() etc, where the user
1480 # *knows* only one result will come back. In these cases the ->all
1481 # is not a pessimization, but rather something we actually want
1483 'Unable to properly collapse has_many results in iterator mode due '
1484 . 'to order criteria - performed an eager cursor slurp underneath. '
1485 . 'Consider using ->all() instead'
1486 ) if ( ! $fetch_all and @$rows > 1 );
1491 =head2 result_source
1495 =item Arguments: L<$result_source?|DBIx::Class::ResultSource>
1497 =item Return Value: L<$result_source|DBIx::Class::ResultSource>
1501 An accessor for the primary ResultSource object from which this ResultSet
1508 =item Arguments: $result_class?
1510 =item Return Value: $result_class
1514 An accessor for the class to use when creating result objects. Defaults to
1515 C<< result_source->result_class >> - which in most cases is the name of the
1516 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1518 Note that changing the result_class will also remove any components
1519 that were originally loaded in the source class via
1520 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1521 in the original source class will not run.
1526 my ($self, $result_class) = @_;
1527 if ($result_class) {
1529 # don't fire this for an object
1530 $self->ensure_class_loaded($result_class)
1531 unless ref($result_class);
1533 if ($self->get_cache) {
1534 carp_unique('Changing the result_class of a ResultSet instance with cached results is a noop - the cache contents will not be altered');
1536 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1537 elsif ($self->{cursor} && $self->{cursor}{_pos}) {
1538 $self->throw_exception('Changing the result_class of a ResultSet instance with an active cursor is not supported');
1541 $self->_result_class($result_class);
1543 delete $self->{_result_inflator};
1545 $self->_result_class;
1552 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1554 =item Return Value: $count
1558 Performs an SQL C<COUNT> with the same query as the resultset was built
1559 with to find the number of elements. Passing arguments is equivalent to
1560 C<< $rs->search ($cond, \%attrs)->count >>
1566 return $self->search(@_)->count if @_ and defined $_[0];
1567 return scalar @{ $self->get_cache } if $self->get_cache;
1569 my $attrs = { %{ $self->_resolved_attrs } };
1571 # this is a little optimization - it is faster to do the limit
1572 # adjustments in software, instead of a subquery
1573 my ($rows, $offset) = delete @{$attrs}{qw/rows offset/};
1576 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1577 $crs = $self->_count_subq_rs ($attrs);
1580 $crs = $self->_count_rs ($attrs);
1582 my $count = $crs->next;
1584 $count -= $offset if $offset;
1585 $count = $rows if $rows and $rows < $count;
1586 $count = 0 if ($count < 0);
1595 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1597 =item Return Value: L<$count_rs|DBIx::Class::ResultSetColumn>
1601 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1602 This can be very handy for subqueries:
1604 ->search( { amount => $some_rs->count_rs->as_query } )
1606 As with regular resultsets the SQL query will be executed only after
1607 the resultset is accessed via L</next> or L</all>. That would return
1608 the same single value obtainable via L</count>.
1614 return $self->search(@_)->count_rs if @_;
1616 # this may look like a lack of abstraction (count() does about the same)
1617 # but in fact an _rs *must* use a subquery for the limits, as the
1618 # software based limiting can not be ported if this $rs is to be used
1619 # in a subquery itself (i.e. ->as_query)
1620 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1621 return $self->_count_subq_rs($self->{_attrs});
1624 return $self->_count_rs($self->{_attrs});
1629 # returns a ResultSetColumn object tied to the count query
1632 my ($self, $attrs) = @_;
1634 my $rsrc = $self->result_source;
1636 my $tmp_attrs = { %$attrs };
1637 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1638 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1640 # overwrite the selector (supplied by the storage)
1641 $rsrc->resultset_class->new($rsrc, {
1643 select => $rsrc->storage->_count_select ($rsrc, $attrs),
1645 })->get_column ('count');
1649 # same as above but uses a subquery
1651 sub _count_subq_rs {
1652 my ($self, $attrs) = @_;
1654 my $rsrc = $self->result_source;
1656 my $sub_attrs = { %$attrs };
1657 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1658 delete @{$sub_attrs}{qw/collapse columns as select order_by for/};
1660 # if we multi-prefetch we group_by something unique, as this is what we would
1661 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1662 if ( $attrs->{collapse} ) {
1663 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1664 $rsrc->_identifying_column_set || $self->throw_exception(
1665 'Unable to construct a unique group_by criteria properly collapsing the '
1666 . 'has_many prefetch before count()'
1671 # Calculate subquery selector
1672 if (my $g = $sub_attrs->{group_by}) {
1674 my $sql_maker = $rsrc->storage->sql_maker;
1676 # necessary as the group_by may refer to aliased functions
1678 for my $sel (@{$attrs->{select}}) {
1679 $sel_index->{$sel->{-as}} = $sel
1680 if (ref $sel eq 'HASH' and $sel->{-as});
1683 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1684 # also look for named aggregates referred in the having clause
1685 # having often contains scalarrefs - thus parse it out entirely
1687 if ($attrs->{having}) {
1688 local $sql_maker->{having_bind};
1689 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1690 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1691 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1692 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1693 # if we don't unset it we screw up retarded but unfortunately working
1694 # 'MAX(foo.bar)' => { '>', 3 }
1695 $sql_maker->{name_sep} = '';
1698 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1700 my $having_sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1703 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1704 # and if all fails for an utterly naive quoted scalar-with-function
1705 while ($having_sql =~ /
1706 $rquote $sep $lquote (.+?) $rquote
1708 [\s,] \w+ \. (\w+) [\s,]
1710 [\s,] $lquote (.+?) $rquote [\s,]
1712 my $part = $1 || $2 || $3; # one of them matched if we got here
1713 unless ($seen_having{$part}++) {
1720 my $colpiece = $sel_index->{$_} || $_;
1722 # unqualify join-based group_by's. Arcane but possible query
1723 # also horrible horrible hack to alias a column (not a func.)
1724 # (probably need to introduce SQLA syntax)
1725 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1728 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1730 push @{$sub_attrs->{select}}, $colpiece;
1734 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1735 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1738 return $rsrc->resultset_class
1739 ->new ($rsrc, $sub_attrs)
1741 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1742 ->get_column ('count');
1746 =head2 count_literal
1748 B<CAVEAT>: C<count_literal> is provided for Class::DBI compatibility and
1749 should only be used in that context. See L</search_literal> for further info.
1753 =item Arguments: $sql_fragment, @standalone_bind_values
1755 =item Return Value: $count
1759 Counts the results in a literal query. Equivalent to calling L</search_literal>
1760 with the passed arguments, then L</count>.
1764 sub count_literal { shift->search_literal(@_)->count; }
1770 =item Arguments: none
1772 =item Return Value: L<@result_objs|DBIx::Class::Manual::ResultClass>
1776 Returns all elements in the resultset.
1783 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1786 delete @{$self}{qw/_stashed_rows _stashed_results/};
1788 if (my $c = $self->get_cache) {
1792 $self->cursor->reset;
1794 my $objs = $self->_construct_results('fetch_all') || [];
1796 $self->set_cache($objs) if $self->{attrs}{cache};
1805 =item Arguments: none
1807 =item Return Value: $self
1811 Resets the resultset's cursor, so you can iterate through the elements again.
1812 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1820 delete @{$self}{qw/_stashed_rows _stashed_results/};
1821 $self->{all_cache_position} = 0;
1822 $self->cursor->reset;
1830 =item Arguments: none
1832 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1836 L<Resets|/reset> the resultset (causing a fresh query to storage) and returns
1837 an object for the first result (or C<undef> if the resultset is empty).
1842 return $_[0]->reset->next;
1848 # Determines whether and what type of subquery is required for the $rs operation.
1849 # If grouping is necessary either supplies its own, or verifies the current one
1850 # After all is done delegates to the proper storage method.
1852 sub _rs_update_delete {
1853 my ($self, $op, $values) = @_;
1855 my $rsrc = $self->result_source;
1856 my $storage = $rsrc->schema->storage;
1858 my $attrs = { %{$self->_resolved_attrs} };
1860 my $join_classifications;
1861 my ($existing_group_by) = delete @{$attrs}{qw(group_by _grouped_by_distinct)};
1863 # do we need a subquery for any reason?
1865 defined $existing_group_by
1867 # if {from} is unparseable wrap a subq
1868 ref($attrs->{from}) ne 'ARRAY'
1870 # limits call for a subq
1871 $self->_has_resolved_attr(qw/rows offset/)
1874 # simplify the joinmap, so we can further decide if a subq is necessary
1875 if (!$needs_subq and @{$attrs->{from}} > 1) {
1877 ($attrs->{from}, $join_classifications) =
1878 $storage->_prune_unused_joins ($attrs);
1880 # any non-pruneable non-local restricting joins imply subq
1881 $needs_subq = defined List::Util::first { $_ ne $attrs->{alias} } keys %{ $join_classifications->{restricting} || {} };
1884 # check if the head is composite (by now all joins are thrown out unless $needs_subq)
1886 (ref $attrs->{from}[0]) ne 'HASH'
1888 ref $attrs->{from}[0]{ $attrs->{from}[0]{-alias} }
1892 # do we need anything like a subquery?
1893 if (! $needs_subq) {
1894 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1895 # a condition containing 'me' or other table prefixes will not work
1896 # at all. Tell SQLMaker to dequalify idents via a gross hack.
1898 my $sqla = $rsrc->storage->sql_maker;
1899 local $sqla->{_dequalify_idents} = 1;
1900 \[ $sqla->_recurse_where($self->{cond}) ];
1904 # we got this far - means it is time to wrap a subquery
1905 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1907 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1913 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1914 delete $attrs->{$_} for qw/select as collapse/;
1915 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1917 # this will be consumed by the pruner waaaaay down the stack
1918 $attrs->{_force_prune_multiplying_joins} = 1;
1920 my $subrs = (ref $self)->new($rsrc, $attrs);
1922 if (@$idcols == 1) {
1923 $cond = { $idcols->[0] => { -in => $subrs->as_query } };
1925 elsif ($storage->_use_multicolumn_in) {
1926 # no syntax for calling this properly yet
1927 # !!! EXPERIMENTAL API !!! WILL CHANGE !!!
1928 $cond = $storage->sql_maker->_where_op_multicolumn_in (
1929 $idcols, # how do I convey a list of idents...? can binds reside on lhs?
1934 # if all else fails - get all primary keys and operate over a ORed set
1935 # wrap in a transaction for consistency
1936 # this is where the group_by/multiplication starts to matter
1940 # we do not need to check pre-multipliers, since if the premulti is there, its
1941 # parent (who is multi) will be there too
1942 keys %{ $join_classifications->{multiplying} || {} }
1944 # make sure if there is a supplied group_by it matches the columns compiled above
1945 # perfectly. Anything else can not be sanely executed on most databases so croak
1946 # right then and there
1947 if ($existing_group_by) {
1948 my @current_group_by = map
1949 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1954 join ("\x00", sort @current_group_by)
1956 join ("\x00", sort @{$attrs->{columns}} )
1958 $self->throw_exception (
1959 "You have just attempted a $op operation on a resultset which does group_by"
1960 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1961 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1962 . ' kind of queries. Please retry the operation with a modified group_by or'
1963 . ' without using one at all.'
1968 $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
1971 $guard = $storage->txn_scope_guard;
1974 for my $row ($subrs->cursor->all) {
1976 { $idcols->[$_] => $row->[$_] }
1983 my $res = $storage->$op (
1985 $op eq 'update' ? $values : (),
1989 $guard->commit if $guard;
1998 =item Arguments: \%values
2000 =item Return Value: $underlying_storage_rv
2004 Sets the specified columns in the resultset to the supplied values in a
2005 single query. Note that this will not run any accessor/set_column/update
2006 triggers, nor will it update any result object instances derived from this
2007 resultset (this includes the contents of the L<resultset cache|/set_cache>
2008 if any). See L</update_all> if you need to execute any on-update
2009 triggers or cascades defined either by you or a
2010 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2012 The return value is a pass through of what the underlying
2013 storage backend returned, and may vary. See L<DBI/execute> for the most
2018 Note that L</update> does not process/deflate any of the values passed in.
2019 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
2020 ensure manually that any value passed to this method will stringify to
2021 something the RDBMS knows how to deal with. A notable example is the
2022 handling of L<DateTime> objects, for more info see:
2023 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
2028 my ($self, $values) = @_;
2029 $self->throw_exception('Values for update must be a hash')
2030 unless ref $values eq 'HASH';
2032 return $self->_rs_update_delete ('update', $values);
2039 =item Arguments: \%values
2041 =item Return Value: 1
2045 Fetches all objects and updates them one at a time via
2046 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
2047 triggers, while L</update> will not.
2052 my ($self, $values) = @_;
2053 $self->throw_exception('Values for update_all must be a hash')
2054 unless ref $values eq 'HASH';
2056 my $guard = $self->result_source->schema->txn_scope_guard;
2057 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
2066 =item Arguments: none
2068 =item Return Value: $underlying_storage_rv
2072 Deletes the rows matching this resultset in a single query. Note that this
2073 will not run any delete triggers, nor will it alter the
2074 L<in_storage|DBIx::Class::Row/in_storage> status of any result object instances
2075 derived from this resultset (this includes the contents of the
2076 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
2077 execute any on-delete triggers or cascades defined either by you or a
2078 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2080 The return value is a pass through of what the underlying storage backend
2081 returned, and may vary. See L<DBI/execute> for the most common case.
2087 $self->throw_exception('delete does not accept any arguments')
2090 return $self->_rs_update_delete ('delete');
2097 =item Arguments: none
2099 =item Return Value: 1
2103 Fetches all objects and deletes them one at a time via
2104 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2105 triggers, while L</delete> will not.
2111 $self->throw_exception('delete_all does not accept any arguments')
2114 my $guard = $self->result_source->schema->txn_scope_guard;
2115 $_->delete for $self->all;
2124 =item Arguments: [ \@column_list, \@row_values+ ] | [ \%col_data+ ]
2126 =item Return Value: L<\@result_objects|DBIx::Class::Manual::ResultClass> (scalar context) | L<@result_objects|DBIx::Class::Manual::ResultClass> (list context)
2130 Accepts either an arrayref of hashrefs or alternatively an arrayref of
2137 The context of this method call has an important effect on what is
2138 submitted to storage. In void context data is fed directly to fastpath
2139 insertion routines provided by the underlying storage (most often
2140 L<DBI/execute_for_fetch>), bypassing the L<new|DBIx::Class::Row/new> and
2141 L<insert|DBIx::Class::Row/insert> calls on the
2142 L<Result|DBIx::Class::Manual::ResultClass> class, including any
2143 augmentation of these methods provided by components. For example if you
2144 are using something like L<DBIx::Class::UUIDColumns> to create primary
2145 keys for you, you will find that your PKs are empty. In this case you
2146 will have to explicitly force scalar or list context in order to create
2151 In non-void (scalar or list) context, this method is simply a wrapper
2152 for L</create>. Depending on list or scalar context either a list of
2153 L<Result|DBIx::Class::Manual::ResultClass> objects or an arrayref
2154 containing these objects is returned.
2156 When supplying data in "arrayref of arrayrefs" invocation style, the
2157 first element should be a list of column names and each subsequent
2158 element should be a data value in the earlier specified column order.
2161 $schema->resultset("Artist")->populate([
2162 [ qw( artistid name ) ],
2163 [ 100, 'A Formally Unknown Singer' ],
2164 [ 101, 'A singer that jumped the shark two albums ago' ],
2165 [ 102, 'An actually cool singer' ],
2168 For the arrayref of hashrefs style each hashref should be a structure
2169 suitable for passing to L</create>. Multi-create is also permitted with
2172 $schema->resultset("Artist")->populate([
2173 { artistid => 4, name => 'Manufactured Crap', cds => [
2174 { title => 'My First CD', year => 2006 },
2175 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2178 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2179 { title => 'My parents sold me to a record company', year => 2005 },
2180 { title => 'Why Am I So Ugly?', year => 2006 },
2181 { title => 'I Got Surgery and am now Popular', year => 2007 }
2186 If you attempt a void-context multi-create as in the example above (each
2187 Artist also has the related list of CDs), and B<do not> supply the
2188 necessary autoinc foreign key information, this method will proxy to the
2189 less efficient L</create>, and then throw the Result objects away. In this
2190 case there are obviously no benefits to using this method over L</create>.
2197 # cruft placed in standalone method
2198 my $data = $self->_normalize_populate_args(@_);
2200 return unless @$data;
2202 if(defined wantarray) {
2203 my @created = map { $self->create($_) } @$data;
2204 return wantarray ? @created : \@created;
2207 my $first = $data->[0];
2209 # if a column is a registered relationship, and is a non-blessed hash/array, consider
2210 # it relationship data
2211 my (@rels, @columns);
2212 my $rsrc = $self->result_source;
2213 my $rels = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2214 for (keys %$first) {
2215 my $ref = ref $first->{$_};
2216 $rels->{$_} && ($ref eq 'ARRAY' or $ref eq 'HASH')
2222 my @pks = $rsrc->primary_columns;
2224 ## do the belongs_to relationships
2225 foreach my $index (0..$#$data) {
2227 # delegate to create() for any dataset without primary keys with specified relationships
2228 if (grep { !defined $data->[$index]->{$_} } @pks ) {
2230 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
2231 my @ret = $self->populate($data);
2237 foreach my $rel (@rels) {
2238 next unless ref $data->[$index]->{$rel} eq "HASH";
2239 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
2240 my ($reverse_relname, $reverse_relinfo) = %{$rsrc->reverse_relationship_info($rel)};
2241 my $related = $result->result_source->_resolve_condition(
2242 $reverse_relinfo->{cond},
2248 delete $data->[$index]->{$rel};
2249 $data->[$index] = {%{$data->[$index]}, %$related};
2251 push @columns, keys %$related if $index == 0;
2255 ## inherit the data locked in the conditions of the resultset
2256 my ($rs_data) = $self->_merge_with_rscond({});
2257 delete @{$rs_data}{@columns};
2259 ## do bulk insert on current row
2260 $rsrc->storage->insert_bulk(
2262 [@columns, keys %$rs_data],
2263 [ map { [ @$_{@columns}, values %$rs_data ] } @$data ],
2266 ## do the has_many relationships
2267 foreach my $item (@$data) {
2271 foreach my $rel (@rels) {
2272 next unless ref $item->{$rel} eq "ARRAY" && @{ $item->{$rel} };
2274 $main_row ||= $self->new_result({map { $_ => $item->{$_} } @pks});
2276 my $child = $main_row->$rel;
2278 my $related = $child->result_source->_resolve_condition(
2279 $rels->{$rel}{cond},
2285 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
2286 my @populate = map { {%$_, %$related} } @rows_to_add;
2288 $child->populate( \@populate );
2295 # populate() arguments went over several incarnations
2296 # What we ultimately support is AoH
2297 sub _normalize_populate_args {
2298 my ($self, $arg) = @_;
2300 if (ref $arg eq 'ARRAY') {
2304 elsif (ref $arg->[0] eq 'HASH') {
2307 elsif (ref $arg->[0] eq 'ARRAY') {
2309 my @colnames = @{$arg->[0]};
2310 foreach my $values (@{$arg}[1 .. $#$arg]) {
2311 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
2317 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2324 =item Arguments: none
2326 =item Return Value: L<$pager|Data::Page>
2330 Returns a L<Data::Page> object for the current resultset. Only makes
2331 sense for queries with a C<page> attribute.
2333 To get the full count of entries for a paged resultset, call
2334 C<total_entries> on the L<Data::Page> object.
2341 return $self->{pager} if $self->{pager};
2343 my $attrs = $self->{attrs};
2344 if (!defined $attrs->{page}) {
2345 $self->throw_exception("Can't create pager for non-paged rs");
2347 elsif ($attrs->{page} <= 0) {
2348 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2350 $attrs->{rows} ||= 10;
2352 # throw away the paging flags and re-run the count (possibly
2353 # with a subselect) to get the real total count
2354 my $count_attrs = { %$attrs };
2355 delete @{$count_attrs}{qw/rows offset page pager/};
2357 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2359 require DBIx::Class::ResultSet::Pager;
2360 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2361 sub { $total_rs->count }, #lazy-get the total
2363 $self->{attrs}{page},
2371 =item Arguments: $page_number
2373 =item Return Value: L<$resultset|/search>
2377 Returns a resultset for the $page_number page of the resultset on which page
2378 is called, where each page contains a number of rows equal to the 'rows'
2379 attribute set on the resultset (10 by default).
2384 my ($self, $page) = @_;
2385 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2392 =item Arguments: \%col_data
2394 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2398 Creates a new result object in the resultset's result class and returns
2399 it. The row is not inserted into the database at this point, call
2400 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2401 will tell you whether the result object has been inserted or not.
2403 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2408 my ($self, $values) = @_;
2410 $self->throw_exception( "new_result takes only one argument - a hashref of values" )
2413 $self->throw_exception( "new_result expects a hashref" )
2414 unless (ref $values eq 'HASH');
2416 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2418 my $new = $self->result_class->new({
2420 ( @$cols_from_relations
2421 ? (-cols_from_relations => $cols_from_relations)
2424 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2428 reftype($new) eq 'HASH'
2434 carp_unique (sprintf (
2435 "%s->new returned a blessed empty hashref - a strong indicator something is wrong with its inheritance chain",
2436 $self->result_class,
2443 # _merge_with_rscond
2445 # Takes a simple hash of K/V data and returns its copy merged with the
2446 # condition already present on the resultset. Additionally returns an
2447 # arrayref of value/condition names, which were inferred from related
2448 # objects (this is needed for in-memory related objects)
2449 sub _merge_with_rscond {
2450 my ($self, $data) = @_;
2452 my (%new_data, @cols_from_relations);
2454 my $alias = $self->{attrs}{alias};
2456 if (! defined $self->{cond}) {
2457 # just massage $data below
2459 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
2460 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
2461 @cols_from_relations = keys %new_data;
2463 elsif (ref $self->{cond} ne 'HASH') {
2464 $self->throw_exception(
2465 "Can't abstract implicit construct, resultset condition not a hash"
2469 # precedence must be given to passed values over values inherited from
2470 # the cond, so the order here is important.
2471 my $collapsed_cond = $self->_collapse_cond($self->{cond});
2472 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
2474 while ( my($col, $value) = each %implied ) {
2475 my $vref = ref $value;
2481 (keys %$value)[0] eq '='
2483 $new_data{$col} = $value->{'='};
2485 elsif( !$vref or $vref eq 'SCALAR' or blessed($value) ) {
2486 $new_data{$col} = $value;
2493 %{ $self->_remove_alias($data, $alias) },
2496 return (\%new_data, \@cols_from_relations);
2499 # _has_resolved_attr
2501 # determines if the resultset defines at least one
2502 # of the attributes supplied
2504 # used to determine if a subquery is necessary
2506 # supports some virtual attributes:
2508 # This will scan for any joins being present on the resultset.
2509 # It is not a mere key-search but a deep inspection of {from}
2512 sub _has_resolved_attr {
2513 my ($self, @attr_names) = @_;
2515 my $attrs = $self->_resolved_attrs;
2519 for my $n (@attr_names) {
2520 if (grep { $n eq $_ } (qw/-join/) ) {
2521 $extra_checks{$n}++;
2525 my $attr = $attrs->{$n};
2527 next if not defined $attr;
2529 if (ref $attr eq 'HASH') {
2530 return 1 if keys %$attr;
2532 elsif (ref $attr eq 'ARRAY') {
2540 # a resolved join is expressed as a multi-level from
2542 $extra_checks{-join}
2544 ref $attrs->{from} eq 'ARRAY'
2546 @{$attrs->{from}} > 1
2554 # Recursively collapse the condition.
2556 sub _collapse_cond {
2557 my ($self, $cond, $collapsed) = @_;
2561 if (ref $cond eq 'ARRAY') {
2562 foreach my $subcond (@$cond) {
2563 next unless ref $subcond; # -or
2564 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2567 elsif (ref $cond eq 'HASH') {
2568 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2569 foreach my $subcond (@{$cond->{-and}}) {
2570 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2574 foreach my $col (keys %$cond) {
2575 my $value = $cond->{$col};
2576 $collapsed->{$col} = $value;
2586 # Remove the specified alias from the specified query hash. A copy is made so
2587 # the original query is not modified.
2590 my ($self, $query, $alias) = @_;
2592 my %orig = %{ $query || {} };
2595 foreach my $key (keys %orig) {
2597 $unaliased{$key} = $orig{$key};
2600 $unaliased{$1} = $orig{$key}
2601 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2611 =item Arguments: none
2613 =item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
2617 Returns the SQL query and bind vars associated with the invocant.
2619 This is generally used as the RHS for a subquery.
2626 my $attrs = { %{ $self->_resolved_attrs } };
2628 my $aq = $self->result_source->storage->_select_args_to_query (
2629 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
2639 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2641 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2645 my $artist = $schema->resultset('Artist')->find_or_new(
2646 { artist => 'fred' }, { key => 'artists' });
2648 $cd->cd_to_producer->find_or_new({ producer => $producer },
2649 { key => 'primary' });
2651 Find an existing record from this resultset using L</find>. if none exists,
2652 instantiate a new result object and return it. The object will not be saved
2653 into your storage until you call L<DBIx::Class::Row/insert> on it.
2655 You most likely want this method when looking for existing rows using a unique
2656 constraint that is not the primary key, or looking for related rows.
2658 If you want objects to be saved immediately, use L</find_or_create> instead.
2660 B<Note>: Make sure to read the documentation of L</find> and understand the
2661 significance of the C<key> attribute, as its lack may skew your search, and
2662 subsequently result in spurious new objects.
2664 B<Note>: Take care when using C<find_or_new> with a table having
2665 columns with default values that you intend to be automatically
2666 supplied by the database (e.g. an auto_increment primary key column).
2667 In normal usage, the value of such columns should NOT be included at
2668 all in the call to C<find_or_new>, even when set to C<undef>.
2674 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2675 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2676 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2679 return $self->new_result($hash);
2686 =item Arguments: \%col_data
2688 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2692 Attempt to create a single new row or a row with multiple related rows
2693 in the table represented by the resultset (and related tables). This
2694 will not check for duplicate rows before inserting, use
2695 L</find_or_create> to do that.
2697 To create one row for this resultset, pass a hashref of key/value
2698 pairs representing the columns of the table and the values you wish to
2699 store. If the appropriate relationships are set up, foreign key fields
2700 can also be passed an object representing the foreign row, and the
2701 value will be set to its primary key.
2703 To create related objects, pass a hashref of related-object column values
2704 B<keyed on the relationship name>. If the relationship is of type C<multi>
2705 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2706 The process will correctly identify columns holding foreign keys, and will
2707 transparently populate them from the keys of the corresponding relation.
2708 This can be applied recursively, and will work correctly for a structure
2709 with an arbitrary depth and width, as long as the relationships actually
2710 exists and the correct column data has been supplied.
2712 Instead of hashrefs of plain related data (key/value pairs), you may
2713 also pass new or inserted objects. New objects (not inserted yet, see
2714 L</new_result>), will be inserted into their appropriate tables.
2716 Effectively a shortcut for C<< ->new_result(\%col_data)->insert >>.
2718 Example of creating a new row.
2720 $person_rs->create({
2721 name=>"Some Person",
2722 email=>"somebody@someplace.com"
2725 Example of creating a new row and also creating rows in a related C<has_many>
2726 or C<has_one> resultset. Note Arrayref.
2729 { artistid => 4, name => 'Manufactured Crap', cds => [
2730 { title => 'My First CD', year => 2006 },
2731 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2736 Example of creating a new row and also creating a row in a related
2737 C<belongs_to> resultset. Note Hashref.
2740 title=>"Music for Silly Walks",
2743 name=>"Silly Musician",
2751 When subclassing ResultSet never attempt to override this method. Since
2752 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2753 lot of the internals simply never call it, so your override will be
2754 bypassed more often than not. Override either L<DBIx::Class::Row/new>
2755 or L<DBIx::Class::Row/insert> depending on how early in the
2756 L</create> process you need to intervene. See also warning pertaining to
2764 my ($self, $col_data) = @_;
2765 $self->throw_exception( "create needs a hashref" )
2766 unless ref $col_data eq 'HASH';
2767 return $self->new_result($col_data)->insert;
2770 =head2 find_or_create
2774 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2776 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2780 $cd->cd_to_producer->find_or_create({ producer => $producer },
2781 { key => 'primary' });
2783 Tries to find a record based on its primary key or unique constraints; if none
2784 is found, creates one and returns that instead.
2786 my $cd = $schema->resultset('CD')->find_or_create({
2788 artist => 'Massive Attack',
2789 title => 'Mezzanine',
2793 Also takes an optional C<key> attribute, to search by a specific key or unique
2794 constraint. For example:
2796 my $cd = $schema->resultset('CD')->find_or_create(
2798 artist => 'Massive Attack',
2799 title => 'Mezzanine',
2801 { key => 'cd_artist_title' }
2804 B<Note>: Make sure to read the documentation of L</find> and understand the
2805 significance of the C<key> attribute, as its lack may skew your search, and
2806 subsequently result in spurious row creation.
2808 B<Note>: Because find_or_create() reads from the database and then
2809 possibly inserts based on the result, this method is subject to a race
2810 condition. Another process could create a record in the table after
2811 the find has completed and before the create has started. To avoid
2812 this problem, use find_or_create() inside a transaction.
2814 B<Note>: Take care when using C<find_or_create> with a table having
2815 columns with default values that you intend to be automatically
2816 supplied by the database (e.g. an auto_increment primary key column).
2817 In normal usage, the value of such columns should NOT be included at
2818 all in the call to C<find_or_create>, even when set to C<undef>.
2820 See also L</find> and L</update_or_create>. For information on how to declare
2821 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2823 If you need to know if an existing row was found or a new one created use
2824 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2825 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2828 my $cd = $schema->resultset('CD')->find_or_new({
2830 artist => 'Massive Attack',
2831 title => 'Mezzanine',
2835 if( !$cd->in_storage ) {
2842 sub find_or_create {
2844 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2845 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2846 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2849 return $self->create($hash);
2852 =head2 update_or_create
2856 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2858 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2862 $resultset->update_or_create({ col => $val, ... });
2864 Like L</find_or_create>, but if a row is found it is immediately updated via
2865 C<< $found_row->update (\%col_data) >>.
2868 Takes an optional C<key> attribute to search on a specific unique constraint.
2871 # In your application
2872 my $cd = $schema->resultset('CD')->update_or_create(
2874 artist => 'Massive Attack',
2875 title => 'Mezzanine',
2878 { key => 'cd_artist_title' }
2881 $cd->cd_to_producer->update_or_create({
2882 producer => $producer,
2888 B<Note>: Make sure to read the documentation of L</find> and understand the
2889 significance of the C<key> attribute, as its lack may skew your search, and
2890 subsequently result in spurious row creation.
2892 B<Note>: Take care when using C<update_or_create> with a table having
2893 columns with default values that you intend to be automatically
2894 supplied by the database (e.g. an auto_increment primary key column).
2895 In normal usage, the value of such columns should NOT be included at
2896 all in the call to C<update_or_create>, even when set to C<undef>.
2898 See also L</find> and L</find_or_create>. For information on how to declare
2899 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2901 If you need to know if an existing row was updated or a new one created use
2902 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2903 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2908 sub update_or_create {
2910 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2911 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2913 my $row = $self->find($cond, $attrs);
2915 $row->update($cond);
2919 return $self->create($cond);
2922 =head2 update_or_new
2926 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2928 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2932 $resultset->update_or_new({ col => $val, ... });
2934 Like L</find_or_new> but if a row is found it is immediately updated via
2935 C<< $found_row->update (\%col_data) >>.
2939 # In your application
2940 my $cd = $schema->resultset('CD')->update_or_new(
2942 artist => 'Massive Attack',
2943 title => 'Mezzanine',
2946 { key => 'cd_artist_title' }
2949 if ($cd->in_storage) {
2950 # the cd was updated
2953 # the cd is not yet in the database, let's insert it
2957 B<Note>: Make sure to read the documentation of L</find> and understand the
2958 significance of the C<key> attribute, as its lack may skew your search, and
2959 subsequently result in spurious new objects.
2961 B<Note>: Take care when using C<update_or_new> with a table having
2962 columns with default values that you intend to be automatically
2963 supplied by the database (e.g. an auto_increment primary key column).
2964 In normal usage, the value of such columns should NOT be included at
2965 all in the call to C<update_or_new>, even when set to C<undef>.
2967 See also L</find>, L</find_or_create> and L</find_or_new>.
2973 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2974 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2976 my $row = $self->find( $cond, $attrs );
2977 if ( defined $row ) {
2978 $row->update($cond);
2982 return $self->new_result($cond);
2989 =item Arguments: none
2991 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass> | undef
2995 Gets the contents of the cache for the resultset, if the cache is set.
2997 The cache is populated either by using the L</prefetch> attribute to
2998 L</search> or by calling L</set_cache>.
3010 =item Arguments: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3012 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3016 Sets the contents of the cache for the resultset. Expects an arrayref
3017 of objects of the same class as those produced by the resultset. Note that
3018 if the cache is set, the resultset will return the cached objects rather
3019 than re-querying the database even if the cache attr is not set.
3021 The contents of the cache can also be populated by using the
3022 L</prefetch> attribute to L</search>.
3027 my ( $self, $data ) = @_;
3028 $self->throw_exception("set_cache requires an arrayref")
3029 if defined($data) && (ref $data ne 'ARRAY');
3030 $self->{all_cache} = $data;
3037 =item Arguments: none
3039 =item Return Value: undef
3043 Clears the cache for the resultset.
3048 shift->set_cache(undef);
3055 =item Arguments: none
3057 =item Return Value: true, if the resultset has been paginated
3065 return !!$self->{attrs}{page};
3072 =item Arguments: none
3074 =item Return Value: true, if the resultset has been ordered with C<order_by>.
3082 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
3085 =head2 related_resultset
3089 =item Arguments: $rel_name
3091 =item Return Value: L<$resultset|/search>
3095 Returns a related resultset for the supplied relationship name.
3097 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
3101 sub related_resultset {
3102 my ($self, $rel) = @_;
3104 return $self->{related_resultsets}{$rel}
3105 if defined $self->{related_resultsets}{$rel};
3107 return $self->{related_resultsets}{$rel} = do {
3108 my $rsrc = $self->result_source;
3109 my $rel_info = $rsrc->relationship_info($rel);
3111 $self->throw_exception(
3112 "search_related: result source '" . $rsrc->source_name .
3113 "' has no such relationship $rel")
3116 my $attrs = $self->_chain_relationship($rel);
3118 my $join_count = $attrs->{seen_join}{$rel};
3120 my $alias = $self->result_source->storage
3121 ->relname_to_table_alias($rel, $join_count);
3123 # since this is search_related, and we already slid the select window inwards
3124 # (the select/as attrs were deleted in the beginning), we need to flip all
3125 # left joins to inner, so we get the expected results
3126 # read the comment on top of the actual function to see what this does
3127 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
3130 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3131 delete @{$attrs}{qw(result_class alias)};
3133 my $rel_source = $rsrc->related_source($rel);
3137 # The reason we do this now instead of passing the alias to the
3138 # search_rs below is that if you wrap/overload resultset on the
3139 # source you need to know what alias it's -going- to have for things
3140 # to work sanely (e.g. RestrictWithObject wants to be able to add
3141 # extra query restrictions, and these may need to be $alias.)
3143 my $rel_attrs = $rel_source->resultset_attributes;
3144 local $rel_attrs->{alias} = $alias;
3146 $rel_source->resultset
3150 where => $attrs->{where},
3154 if (my $cache = $self->get_cache) {
3155 my @related_cache = map
3156 { @{$_->related_resultset($rel)->get_cache||[]} }
3160 $new->set_cache(\@related_cache) if @related_cache;
3167 =head2 current_source_alias
3171 =item Arguments: none
3173 =item Return Value: $source_alias
3177 Returns the current table alias for the result source this resultset is built
3178 on, that will be used in the SQL query. Usually it is C<me>.
3180 Currently the source alias that refers to the result set returned by a
3181 L</search>/L</find> family method depends on how you got to the resultset: it's
3182 C<me> by default, but eg. L</search_related> aliases it to the related result
3183 source name (and keeps C<me> referring to the original result set). The long
3184 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3185 (and make this method unnecessary).
3187 Thus it's currently necessary to use this method in predefined queries (see
3188 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3189 source alias of the current result set:
3191 # in a result set class
3193 my ($self, $user) = @_;
3195 my $me = $self->current_source_alias;
3197 return $self->search({
3198 "$me.modified" => $user->id,
3204 sub current_source_alias {
3205 return (shift->{attrs} || {})->{alias} || 'me';
3208 =head2 as_subselect_rs
3212 =item Arguments: none
3214 =item Return Value: L<$resultset|/search>
3218 Act as a barrier to SQL symbols. The resultset provided will be made into a
3219 "virtual view" by including it as a subquery within the from clause. From this
3220 point on, any joined tables are inaccessible to ->search on the resultset (as if
3221 it were simply where-filtered without joins). For example:
3223 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3225 # 'x' now pollutes the query namespace
3227 # So the following works as expected
3228 my $ok_rs = $rs->search({'x.other' => 1});
3230 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3231 # def) we look for one row with contradictory terms and join in another table
3232 # (aliased 'x_2') which we never use
3233 my $broken_rs = $rs->search({'x.name' => 'def'});
3235 my $rs2 = $rs->as_subselect_rs;
3237 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3238 my $not_joined_rs = $rs2->search({'x.other' => 1});
3240 # works as expected: finds a 'table' row related to two x rows (abc and def)
3241 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3243 Another example of when one might use this would be to select a subset of
3244 columns in a group by clause:
3246 my $rs = $schema->resultset('Bar')->search(undef, {
3247 group_by => [qw{ id foo_id baz_id }],
3248 })->as_subselect_rs->search(undef, {
3249 columns => [qw{ id foo_id }]
3252 In the above example normally columns would have to be equal to the group by,
3253 but because we isolated the group by into a subselect the above works.
3257 sub as_subselect_rs {
3260 my $attrs = $self->_resolved_attrs;
3262 my $fresh_rs = (ref $self)->new (
3263 $self->result_source
3266 # these pieces will be locked in the subquery
3267 delete $fresh_rs->{cond};
3268 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3270 return $fresh_rs->search( {}, {
3272 $attrs->{alias} => $self->as_query,
3273 -alias => $attrs->{alias},
3274 -rsrc => $self->result_source,
3276 alias => $attrs->{alias},
3280 # This code is called by search_related, and makes sure there
3281 # is clear separation between the joins before, during, and
3282 # after the relationship. This information is needed later
3283 # in order to properly resolve prefetch aliases (any alias
3284 # with a relation_chain_depth less than the depth of the
3285 # current prefetch is not considered)
3287 # The increments happen twice per join. An even number means a
3288 # relationship specified via a search_related, whereas an odd
3289 # number indicates a join/prefetch added via attributes
3291 # Also this code will wrap the current resultset (the one we
3292 # chain to) in a subselect IFF it contains limiting attributes
3293 sub _chain_relationship {
3294 my ($self, $rel) = @_;
3295 my $source = $self->result_source;
3296 my $attrs = { %{$self->{attrs}||{}} };
3298 # we need to take the prefetch the attrs into account before we
3299 # ->_resolve_join as otherwise they get lost - captainL
3300 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3302 delete @{$attrs}{qw/join prefetch collapse group_by distinct _grouped_by_distinct select as columns +select +as +columns/};
3304 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3307 my @force_subq_attrs = qw/offset rows group_by having/;
3310 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3312 $self->_has_resolved_attr (@force_subq_attrs)
3314 # Nuke the prefetch (if any) before the new $rs attrs
3315 # are resolved (prefetch is useless - we are wrapping
3316 # a subquery anyway).
3317 my $rs_copy = $self->search;
3318 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3319 $rs_copy->{attrs}{join},
3320 delete $rs_copy->{attrs}{prefetch},
3325 -alias => $attrs->{alias},
3326 $attrs->{alias} => $rs_copy->as_query,
3328 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3329 $seen->{-relation_chain_depth} = 0;
3331 elsif ($attrs->{from}) { #shallow copy suffices
3332 $from = [ @{$attrs->{from}} ];
3337 -alias => $attrs->{alias},
3338 $attrs->{alias} => $source->from,
3342 my $jpath = ($seen->{-relation_chain_depth})
3343 ? $from->[-1][0]{-join_path}
3346 my @requested_joins = $source->_resolve_join(
3353 push @$from, @requested_joins;
3355 $seen->{-relation_chain_depth}++;
3357 # if $self already had a join/prefetch specified on it, the requested
3358 # $rel might very well be already included. What we do in this case
3359 # is effectively a no-op (except that we bump up the chain_depth on
3360 # the join in question so we could tell it *is* the search_related)
3363 # we consider the last one thus reverse
3364 for my $j (reverse @requested_joins) {
3365 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3366 if ($rel eq $last_j) {
3367 $j->[0]{-relation_chain_depth}++;
3373 unless ($already_joined) {
3374 push @$from, $source->_resolve_join(
3382 $seen->{-relation_chain_depth}++;
3384 return {%$attrs, from => $from, seen_join => $seen};
3387 sub _resolved_attrs {
3389 return $self->{_attrs} if $self->{_attrs};
3391 my $attrs = { %{ $self->{attrs} || {} } };
3392 my $source = $self->result_source;
3393 my $alias = $attrs->{alias};
3395 $self->throw_exception("Specifying distinct => 1 in conjunction with collapse => 1 is unsupported")
3396 if $attrs->{collapse} and $attrs->{distinct};
3398 # default selection list
3399 $attrs->{columns} = [ $source->columns ]
3400 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3402 # merge selectors together
3403 for (qw/columns select as/) {
3404 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3405 if $attrs->{$_} or $attrs->{"+$_"};
3408 # disassemble columns
3410 if (my $cols = delete $attrs->{columns}) {
3411 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3412 if (ref $c eq 'HASH') {
3413 for my $as (sort keys %$c) {
3414 push @sel, $c->{$as};
3425 # when trying to weed off duplicates later do not go past this point -
3426 # everything added from here on is unbalanced "anyone's guess" stuff
3427 my $dedup_stop_idx = $#as;
3429 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3431 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3432 if $attrs->{select};
3434 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3435 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3437 # disqualify all $alias.col as-bits (inflate-map mandated)
3438 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3440 # de-duplicate the result (remove *identical* select/as pairs)
3441 # and also die on duplicate {as} pointing to different {select}s
3442 # not using a c-style for as the condition is prone to shrinkage
3445 while ($i <= $dedup_stop_idx) {
3446 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3451 elsif ($seen->{$as[$i]}++) {
3452 $self->throw_exception(
3453 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3461 $attrs->{select} = \@sel;
3462 $attrs->{as} = \@as;
3464 $attrs->{from} ||= [{
3466 -alias => $self->{attrs}{alias},
3467 $self->{attrs}{alias} => $source->from,
3470 if ( $attrs->{join} || $attrs->{prefetch} ) {
3472 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3473 if ref $attrs->{from} ne 'ARRAY';
3475 my $join = (delete $attrs->{join}) || {};
3477 if ( defined $attrs->{prefetch} ) {
3478 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3481 $attrs->{from} = # have to copy here to avoid corrupting the original
3483 @{ $attrs->{from} },
3484 $source->_resolve_join(
3487 { %{ $attrs->{seen_join} || {} } },
3488 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3489 ? $attrs->{from}[-1][0]{-join_path}
3496 if ( defined $attrs->{order_by} ) {
3497 $attrs->{order_by} = (
3498 ref( $attrs->{order_by} ) eq 'ARRAY'
3499 ? [ @{ $attrs->{order_by} } ]
3500 : [ $attrs->{order_by} || () ]
3504 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3505 $attrs->{group_by} = [ $attrs->{group_by} ];
3509 # generate selections based on the prefetch helper
3510 my ($prefetch, @prefetch_select, @prefetch_as);
3511 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3512 if defined $attrs->{prefetch};
3516 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3517 if $attrs->{_dark_selector};
3519 $self->throw_exception("Specifying prefetch in conjunction with an explicit collapse => 0 is unsupported")
3520 if defined $attrs->{collapse} and ! $attrs->{collapse};
3522 $attrs->{collapse} = 1;
3524 # this is a separate structure (we don't look in {from} directly)
3525 # as the resolver needs to shift things off the lists to work
3526 # properly (identical-prefetches on different branches)
3528 if (ref $attrs->{from} eq 'ARRAY') {
3530 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3532 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3533 next unless $j->[0]{-alias};
3534 next unless $j->[0]{-join_path};
3535 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3537 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3540 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3541 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3545 my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map );
3547 # save these for after distinct resolution
3548 @prefetch_select = map { $_->[0] } @prefetch;
3549 @prefetch_as = map { $_->[1] } @prefetch;
3552 # run through the resulting joinstructure (starting from our current slot)
3553 # and unset collapse if proven unnecessary
3555 # also while we are at it find out if the current root source has
3556 # been premultiplied by previous related_source chaining
3558 # this allows to predict whether a root object with all other relation
3559 # data set to NULL is in fact unique
3560 if ($attrs->{collapse}) {
3562 if (ref $attrs->{from} eq 'ARRAY') {
3564 if (@{$attrs->{from}} == 1) {
3565 # no joins - no collapse
3566 $attrs->{collapse} = 0;
3569 # find where our table-spec starts
3570 my @fromlist = @{$attrs->{from}};
3572 my $t = shift @fromlist;
3575 # me vs join from-spec distinction - a ref means non-root
3576 if (ref $t eq 'ARRAY') {
3578 $is_multi ||= ! $t->{-is_single};
3580 last if ($t->{-alias} && $t->{-alias} eq $alias);
3581 $attrs->{_main_source_premultiplied} ||= $is_multi;
3584 # no non-singles remaining, nor any premultiplication - nothing to collapse
3586 ! $attrs->{_main_source_premultiplied}
3588 ! List::Util::first { ! $_->[0]{-is_single} } @fromlist
3590 $attrs->{collapse} = 0;
3596 # if we can not analyze the from - err on the side of safety
3597 $attrs->{_main_source_premultiplied} = 1;
3601 # generate the distinct induced group_by before injecting the prefetched select/as parts
3602 if (delete $attrs->{distinct}) {
3603 if ($attrs->{group_by}) {
3604 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3607 $attrs->{_grouped_by_distinct} = 1;
3608 # distinct affects only the main selection part, not what prefetch may add below
3609 ($attrs->{group_by}, my $new_order) = $source->storage->_group_over_selection($attrs);
3611 # FIXME possibly ignore a rewritten order_by (may turn out to be an issue)
3612 # The thinking is: if we are collapsing the subquerying prefetch engine will
3613 # rip stuff apart for us anyway, and we do not want to have a potentially
3614 # function-converted external order_by
3615 # ( there is an explicit if ( collapse && _grouped_by_distinct ) check in DBIHacks )
3616 $attrs->{order_by} = $new_order unless $attrs->{collapse};
3620 # inject prefetch-bound selection (if any)
3621 push @{$attrs->{select}}, @prefetch_select;
3622 push @{$attrs->{as}}, @prefetch_as;
3624 # whether we can get away with the dumbest (possibly DBI-internal) collapser
3625 if ( List::Util::first { $_ =~ /\./ } @{$attrs->{as}} ) {
3626 $attrs->{_related_results_construction} = 1;
3629 # if both page and offset are specified, produce a combined offset
3630 # even though it doesn't make much sense, this is what pre 081xx has
3632 if (my $page = delete $attrs->{page}) {
3634 ($attrs->{rows} * ($page - 1))
3636 ($attrs->{offset} || 0)
3640 return $self->{_attrs} = $attrs;
3644 my ($self, $attr) = @_;
3646 if (ref $attr eq 'HASH') {
3647 return $self->_rollout_hash($attr);
3648 } elsif (ref $attr eq 'ARRAY') {
3649 return $self->_rollout_array($attr);
3655 sub _rollout_array {
3656 my ($self, $attr) = @_;
3659 foreach my $element (@{$attr}) {
3660 if (ref $element eq 'HASH') {
3661 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3662 } elsif (ref $element eq 'ARRAY') {
3663 # XXX - should probably recurse here
3664 push( @rolled_array, @{$self->_rollout_array($element)} );
3666 push( @rolled_array, $element );
3669 return \@rolled_array;
3673 my ($self, $attr) = @_;
3676 foreach my $key (keys %{$attr}) {
3677 push( @rolled_array, { $key => $attr->{$key} } );
3679 return \@rolled_array;
3682 sub _calculate_score {
3683 my ($self, $a, $b) = @_;
3685 if (defined $a xor defined $b) {
3688 elsif (not defined $a) {
3692 if (ref $b eq 'HASH') {
3693 my ($b_key) = keys %{$b};
3694 if (ref $a eq 'HASH') {
3695 my ($a_key) = keys %{$a};
3696 if ($a_key eq $b_key) {
3697 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3702 return ($a eq $b_key) ? 1 : 0;
3705 if (ref $a eq 'HASH') {
3706 my ($a_key) = keys %{$a};
3707 return ($b eq $a_key) ? 1 : 0;
3709 return ($b eq $a) ? 1 : 0;
3714 sub _merge_joinpref_attr {
3715 my ($self, $orig, $import) = @_;
3717 return $import unless defined($orig);
3718 return $orig unless defined($import);
3720 $orig = $self->_rollout_attr($orig);
3721 $import = $self->_rollout_attr($import);
3724 foreach my $import_element ( @{$import} ) {
3725 # find best candidate from $orig to merge $b_element into
3726 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3727 foreach my $orig_element ( @{$orig} ) {
3728 my $score = $self->_calculate_score( $orig_element, $import_element );
3729 if ($score > $best_candidate->{score}) {
3730 $best_candidate->{position} = $position;
3731 $best_candidate->{score} = $score;
3735 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3736 $import_key = '' if not defined $import_key;
3738 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3739 push( @{$orig}, $import_element );
3741 my $orig_best = $orig->[$best_candidate->{position}];
3742 # merge orig_best and b_element together and replace original with merged
3743 if (ref $orig_best ne 'HASH') {
3744 $orig->[$best_candidate->{position}] = $import_element;
3745 } elsif (ref $import_element eq 'HASH') {
3746 my ($key) = keys %{$orig_best};
3747 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3750 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3753 return @$orig ? $orig : ();
3761 require Hash::Merge;
3762 my $hm = Hash::Merge->new;
3764 $hm->specify_behavior({
3767 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3769 if ($defl xor $defr) {
3770 return [ $defl ? $_[0] : $_[1] ];
3775 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3779 return [$_[0], $_[1]];
3783 return $_[1] if !defined $_[0];
3784 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3785 return [$_[0], @{$_[1]}]
3788 return [] if !defined $_[0] and !keys %{$_[1]};
3789 return [ $_[1] ] if !defined $_[0];
3790 return [ $_[0] ] if !keys %{$_[1]};
3791 return [$_[0], $_[1]]
3796 return $_[0] if !defined $_[1];
3797 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3798 return [@{$_[0]}, $_[1]]
3801 my @ret = @{$_[0]} or return $_[1];
3802 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3803 my %idx = map { $_ => 1 } @ret;
3804 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3808 return [ $_[1] ] if ! @{$_[0]};
3809 return $_[0] if !keys %{$_[1]};
3810 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3811 return [ @{$_[0]}, $_[1] ];
3816 return [] if !keys %{$_[0]} and !defined $_[1];
3817 return [ $_[0] ] if !defined $_[1];
3818 return [ $_[1] ] if !keys %{$_[0]};
3819 return [$_[0], $_[1]]
3822 return [] if !keys %{$_[0]} and !@{$_[1]};
3823 return [ $_[0] ] if !@{$_[1]};
3824 return $_[1] if !keys %{$_[0]};
3825 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3826 return [ $_[0], @{$_[1]} ];
3829 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3830 return [ $_[0] ] if !keys %{$_[1]};
3831 return [ $_[1] ] if !keys %{$_[0]};
3832 return [ $_[0] ] if $_[0] eq $_[1];
3833 return [ $_[0], $_[1] ];
3836 } => 'DBIC_RS_ATTR_MERGER');
3840 return $hm->merge ($_[1], $_[2]);
3844 sub STORABLE_freeze {
3845 my ($self, $cloning) = @_;
3846 my $to_serialize = { %$self };
3848 # A cursor in progress can't be serialized (and would make little sense anyway)
3849 # the parser can be regenerated (and can't be serialized)
3850 delete @{$to_serialize}{qw/cursor _row_parser _result_inflator/};
3852 # nor is it sensical to store a not-yet-fired-count pager
3853 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3854 delete $to_serialize->{pager};
3857 Storable::nfreeze($to_serialize);
3860 # need this hook for symmetry
3862 my ($self, $cloning, $serialized) = @_;
3864 %$self = %{ Storable::thaw($serialized) };
3870 =head2 throw_exception
3872 See L<DBIx::Class::Schema/throw_exception> for details.
3876 sub throw_exception {
3879 if (ref $self and my $rsrc = $self->result_source) {
3880 $rsrc->throw_exception(@_)
3883 DBIx::Class::Exception->throw(@_);
3891 # XXX: FIXME: Attributes docs need clearing up
3895 Attributes are used to refine a ResultSet in various ways when
3896 searching for data. They can be passed to any method which takes an
3897 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3900 Default attributes can be set on the result class using
3901 L<DBIx::Class::ResultSource/resultset_attributes>. (Please read
3902 the CAVEATS on that feature before using it!)
3904 These are in no particular order:
3910 =item Value: ( $order_by | \@order_by | \%order_by )
3914 Which column(s) to order the results by.
3916 [The full list of suitable values is documented in
3917 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3920 If a single column name, or an arrayref of names is supplied, the
3921 argument is passed through directly to SQL. The hashref syntax allows
3922 for connection-agnostic specification of ordering direction:
3924 For descending order:
3926 order_by => { -desc => [qw/col1 col2 col3/] }
3928 For explicit ascending order:
3930 order_by => { -asc => 'col' }
3932 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3933 supported, although you are strongly encouraged to use the hashref
3934 syntax as outlined above.
3940 =item Value: \@columns | \%columns | $column
3944 Shortcut to request a particular set of columns to be retrieved. Each
3945 column spec may be a string (a table column name), or a hash (in which
3946 case the key is the C<as> value, and the value is used as the C<select>
3947 expression). Adds C<me.> onto the start of any column without a C<.> in
3948 it and sets C<select> from that, then auto-populates C<as> from
3949 C<select> as normal. (You may also use the C<cols> attribute, as in
3950 earlier versions of DBIC, but this is deprecated.)
3952 Essentially C<columns> does the same as L</select> and L</as>.
3954 columns => [ 'foo', { bar => 'baz' } ]
3958 select => [qw/foo baz/],
3965 =item Value: \@columns
3969 Indicates additional columns to be selected from storage. Works the same as
3970 L</columns> but adds columns to the selection. (You may also use the
3971 C<include_columns> attribute, as in earlier versions of DBIC, but this is
3972 deprecated). For example:-
3974 $schema->resultset('CD')->search(undef, {
3975 '+columns' => ['artist.name'],
3979 would return all CDs and include a 'name' column to the information
3980 passed to object inflation. Note that the 'artist' is the name of the
3981 column (or relationship) accessor, and 'name' is the name of the column
3982 accessor in the related table.
3984 B<NOTE:> You need to explicitly quote '+columns' when defining the attribute.
3985 Not doing so causes Perl to incorrectly interpret +columns as a bareword with a
3986 unary plus operator before it.
3988 =head2 include_columns
3992 =item Value: \@columns
3996 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
4002 =item Value: \@select_columns
4006 Indicates which columns should be selected from the storage. You can use
4007 column names, or in the case of RDBMS back ends, function or stored procedure
4010 $rs = $schema->resultset('Employee')->search(undef, {
4013 { count => 'employeeid' },
4014 { max => { length => 'name' }, -as => 'longest_name' }
4019 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
4021 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
4022 use L</select>, to instruct DBIx::Class how to store the result of the column.
4023 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
4024 identifier aliasing. You can however alias a function, so you can use it in
4025 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
4026 attribute> supplied as shown in the example above.
4028 B<NOTE:> You need to explicitly quote '+select'/'+as' when defining the attributes.
4029 Not doing so causes Perl to incorrectly interpret them as a bareword with a
4030 unary plus operator before it.
4036 Indicates additional columns to be selected from storage. Works the same as
4037 L</select> but adds columns to the default selection, instead of specifying
4046 =item Value: \@inflation_names
4050 Indicates column names for object inflation. That is L</as> indicates the
4051 slot name in which the column value will be stored within the
4052 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
4053 identifier by the C<get_column> method (or via the object accessor B<if one
4054 with the same name already exists>) as shown below. The L</as> attribute has
4055 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
4057 $rs = $schema->resultset('Employee')->search(undef, {
4060 { count => 'employeeid' },
4061 { max => { length => 'name' }, -as => 'longest_name' }
4070 If the object against which the search is performed already has an accessor
4071 matching a column name specified in C<as>, the value can be retrieved using
4072 the accessor as normal:
4074 my $name = $employee->name();
4076 If on the other hand an accessor does not exist in the object, you need to
4077 use C<get_column> instead:
4079 my $employee_count = $employee->get_column('employee_count');
4081 You can create your own accessors if required - see
4082 L<DBIx::Class::Manual::Cookbook> for details.
4088 Indicates additional column names for those added via L</+select>. See L</as>.
4096 =item Value: ($rel_name | \@rel_names | \%rel_names)
4100 Contains a list of relationships that should be joined for this query. For
4103 # Get CDs by Nine Inch Nails
4104 my $rs = $schema->resultset('CD')->search(
4105 { 'artist.name' => 'Nine Inch Nails' },
4106 { join => 'artist' }
4109 Can also contain a hash reference to refer to the other relation's relations.
4112 package MyApp::Schema::Track;
4113 use base qw/DBIx::Class/;
4114 __PACKAGE__->table('track');
4115 __PACKAGE__->add_columns(qw/trackid cd position title/);
4116 __PACKAGE__->set_primary_key('trackid');
4117 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
4120 # In your application
4121 my $rs = $schema->resultset('Artist')->search(
4122 { 'track.title' => 'Teardrop' },
4124 join => { cd => 'track' },
4125 order_by => 'artist.name',
4129 You need to use the relationship (not the table) name in conditions,
4130 because they are aliased as such. The current table is aliased as "me", so
4131 you need to use me.column_name in order to avoid ambiguity. For example:
4133 # Get CDs from 1984 with a 'Foo' track
4134 my $rs = $schema->resultset('CD')->search(
4137 'tracks.name' => 'Foo'
4139 { join => 'tracks' }
4142 If the same join is supplied twice, it will be aliased to <rel>_2 (and
4143 similarly for a third time). For e.g.
4145 my $rs = $schema->resultset('Artist')->search({
4146 'cds.title' => 'Down to Earth',
4147 'cds_2.title' => 'Popular',
4149 join => [ qw/cds cds/ ],
4152 will return a set of all artists that have both a cd with title 'Down
4153 to Earth' and a cd with title 'Popular'.
4155 If you want to fetch related objects from other tables as well, see L</prefetch>
4158 NOTE: An internal join-chain pruner will discard certain joins while
4159 constructing the actual SQL query, as long as the joins in question do not
4160 affect the retrieved result. This for example includes 1:1 left joins
4161 that are not part of the restriction specification (WHERE/HAVING) nor are
4162 a part of the query selection.
4164 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4170 =item Value: (0 | 1)
4174 When set to a true value, indicates that any rows fetched from joined has_many
4175 relationships are to be aggregated into the corresponding "parent" object. For
4176 example, the resultset:
4178 my $rs = $schema->resultset('CD')->search({}, {
4179 '+columns' => [ qw/ tracks.title tracks.position / ],
4184 While executing the following query:
4186 SELECT me.*, tracks.title, tracks.position
4188 LEFT JOIN track tracks
4189 ON tracks.cdid = me.cdid
4191 Will return only as many objects as there are rows in the CD source, even
4192 though the result of the query may span many rows. Each of these CD objects
4193 will in turn have multiple "Track" objects hidden behind the has_many
4194 generated accessor C<tracks>. Without C<< collapse => 1 >>, the return values
4195 of this resultset would be as many CD objects as there are tracks (a "Cartesian
4196 product"), with each CD object containing exactly one of all fetched Track data.
4198 When a collapse is requested on a non-ordered resultset, an order by some
4199 unique part of the main source (the left-most table) is inserted automatically.
4200 This is done so that the resultset is allowed to be "lazy" - calling
4201 L<< $rs->next|/next >> will fetch only as many rows as it needs to build the next
4202 object with all of its related data.
4204 If an L</order_by> is already declared, and orders the resultset in a way that
4205 makes collapsing as described above impossible (e.g. C<< ORDER BY
4206 has_many_rel.column >> or C<ORDER BY RANDOM()>), DBIC will automatically
4207 switch to "eager" mode and slurp the entire resultset before constructing the
4208 first object returned by L</next>.
4210 Setting this attribute on a resultset that does not join any has_many
4211 relations is a no-op.
4213 For a more in-depth discussion, see L</PREFETCHING>.
4219 =item Value: ($rel_name | \@rel_names | \%rel_names)
4223 This attribute is a shorthand for specifying a L</join> spec, adding all
4224 columns from the joined related sources as L</+columns> and setting
4225 L</collapse> to a true value. For example, the following two queries are
4228 my $rs = $schema->resultset('Artist')->search({}, {
4229 prefetch => { cds => ['genre', 'tracks' ] },
4234 my $rs = $schema->resultset('Artist')->search({}, {
4235 join => { cds => ['genre', 'tracks' ] },
4239 { +{ "cds.$_" => "cds.$_" } }
4240 $schema->source('Artist')->related_source('cds')->columns
4243 { +{ "cds.genre.$_" => "genre.$_" } }
4244 $schema->source('Artist')->related_source('cds')->related_source('genre')->columns
4247 { +{ "cds.tracks.$_" => "tracks.$_" } }
4248 $schema->source('Artist')->related_source('cds')->related_source('tracks')->columns
4253 Both producing the following SQL:
4255 SELECT me.artistid, me.name, me.rank, me.charfield,
4256 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track,
4257 genre.genreid, genre.name,
4258 tracks.trackid, tracks.cd, tracks.position, tracks.title, tracks.last_updated_on, tracks.last_updated_at
4261 ON cds.artist = me.artistid
4262 LEFT JOIN genre genre
4263 ON genre.genreid = cds.genreid
4264 LEFT JOIN track tracks
4265 ON tracks.cd = cds.cdid
4266 ORDER BY me.artistid
4268 While L</prefetch> implies a L</join>, it is ok to mix the two together, as
4269 the arguments are properly merged and generally do the right thing. For
4270 example, you may want to do the following:
4272 my $artists_and_cds_without_genre = $schema->resultset('Artist')->search(
4273 { 'genre.genreid' => undef },
4275 join => { cds => 'genre' },
4280 Which generates the following SQL:
4282 SELECT me.artistid, me.name, me.rank, me.charfield,
4283 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track
4286 ON cds.artist = me.artistid
4287 LEFT JOIN genre genre
4288 ON genre.genreid = cds.genreid
4289 WHERE genre.genreid IS NULL
4290 ORDER BY me.artistid
4292 For a more in-depth discussion, see L</PREFETCHING>.
4298 =item Value: $source_alias
4302 Sets the source alias for the query. Normally, this defaults to C<me>, but
4303 nested search queries (sub-SELECTs) might need specific aliases set to
4304 reference inner queries. For example:
4307 ->related_resultset('CDs')
4308 ->related_resultset('Tracks')
4310 'track.id' => { -ident => 'none_search.id' },
4314 my $ids = $self->search({
4317 alias => 'none_search',
4318 group_by => 'none_search.id',
4319 })->get_column('id')->as_query;
4321 $self->search({ id => { -in => $ids } })
4323 This attribute is directly tied to L</current_source_alias>.
4333 Makes the resultset paged and specifies the page to retrieve. Effectively
4334 identical to creating a non-pages resultset and then calling ->page($page)
4337 If L</rows> attribute is not specified it defaults to 10 rows per page.
4339 When you have a paged resultset, L</count> will only return the number
4340 of rows in the page. To get the total, use the L</pager> and call
4341 C<total_entries> on it.
4351 Specifies the maximum number of rows for direct retrieval or the number of
4352 rows per page if the page attribute or method is used.
4358 =item Value: $offset
4362 Specifies the (zero-based) row number for the first row to be returned, or the
4363 of the first row of the first page if paging is used.
4365 =head2 software_limit
4369 =item Value: (0 | 1)
4373 When combined with L</rows> and/or L</offset> the generated SQL will not
4374 include any limit dialect stanzas. Instead the entire result will be selected
4375 as if no limits were specified, and DBIC will perform the limit locally, by
4376 artificially advancing and finishing the resulting L</cursor>.
4378 This is the recommended way of performing resultset limiting when no sane RDBMS
4379 implementation is available (e.g.
4380 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4381 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4387 =item Value: \@columns
4391 A arrayref of columns to group by. Can include columns of joined tables.
4393 group_by => [qw/ column1 column2 ... /]
4399 =item Value: $condition
4403 HAVING is a select statement attribute that is applied between GROUP BY and
4404 ORDER BY. It is applied to the after the grouping calculations have been
4407 having => { 'count_employee' => { '>=', 100 } }
4409 or with an in-place function in which case literal SQL is required:
4411 having => \[ 'count(employee) >= ?', [ count => 100 ] ]
4417 =item Value: (0 | 1)
4421 Set to 1 to automatically generate a L</group_by> clause based on the selection
4422 (including intelligent handling of L</order_by> contents). Note that the group
4423 criteria calculation takes place over the B<final> selection. This includes
4424 any L</+columns>, L</+select> or L</order_by> additions in subsequent
4425 L</search> calls, and standalone columns selected via
4426 L<DBIx::Class::ResultSetColumn> (L</get_column>). A notable exception are the
4427 extra selections specified via L</prefetch> - such selections are explicitly
4428 excluded from group criteria calculations.
4430 If the final ResultSet also explicitly defines a L</group_by> attribute, this
4431 setting is ignored and an appropriate warning is issued.
4437 Adds to the WHERE clause.
4439 # only return rows WHERE deleted IS NULL for all searches
4440 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4442 Can be overridden by passing C<< { where => undef } >> as an attribute
4445 For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
4451 Set to 1 to cache search results. This prevents extra SQL queries if you
4452 revisit rows in your ResultSet:
4454 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4456 while( my $artist = $resultset->next ) {
4460 $rs->first; # without cache, this would issue a query
4462 By default, searches are not cached.
4464 For more examples of using these attributes, see
4465 L<DBIx::Class::Manual::Cookbook>.
4471 =item Value: ( 'update' | 'shared' | \$scalar )
4475 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4476 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4481 DBIx::Class supports arbitrary related data prefetching from multiple related
4482 sources. Any combination of relationship types and column sets are supported.
4483 If L<collapsing|/collapse> is requested, there is an additional requirement of
4484 selecting enough data to make every individual object uniquely identifiable.
4486 Here are some more involved examples, based on the following relationship map:
4489 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4490 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4491 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4493 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4495 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4499 my $rs = $schema->resultset('Tag')->search(
4508 The initial search results in SQL like the following:
4510 SELECT tag.*, cd.*, artist.* FROM tag
4511 JOIN cd ON tag.cd = cd.cdid
4512 JOIN artist ON cd.artist = artist.artistid
4514 L<DBIx::Class> has no need to go back to the database when we access the
4515 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4518 Simple prefetches will be joined automatically, so there is no need
4519 for a C<join> attribute in the above search.
4521 The L</prefetch> attribute can be used with any of the relationship types
4522 and multiple prefetches can be specified together. Below is a more complex
4523 example that prefetches a CD's artist, its liner notes (if present),
4524 the cover image, the tracks on that CD, and the guests on those
4527 my $rs = $schema->resultset('CD')->search(
4531 { artist => 'record_label'}, # belongs_to => belongs_to
4532 'liner_note', # might_have
4533 'cover_image', # has_one
4534 { tracks => 'guests' }, # has_many => has_many
4539 This will produce SQL like the following:
4541 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4545 ON artist.artistid = me.artistid
4546 JOIN record_label record_label
4547 ON record_label.labelid = artist.labelid
4548 LEFT JOIN track tracks
4549 ON tracks.cdid = me.cdid
4550 LEFT JOIN guest guests
4551 ON guests.trackid = track.trackid
4552 LEFT JOIN liner_notes liner_note
4553 ON liner_note.cdid = me.cdid
4554 JOIN cd_artwork cover_image
4555 ON cover_image.cdid = me.cdid
4558 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4559 C<tracks>, and C<guests> of the CD will all be available through the
4560 relationship accessors without the need for additional queries to the
4565 Prefetch does a lot of deep magic. As such, it may not behave exactly
4566 as you might expect.
4572 Prefetch uses the L</cache> to populate the prefetched relationships. This
4573 may or may not be what you want.
4577 If you specify a condition on a prefetched relationship, ONLY those
4578 rows that match the prefetched condition will be fetched into that relationship.
4579 This means that adding prefetch to a search() B<may alter> what is returned by
4580 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4582 my $artist_rs = $schema->resultset('Artist')->search({
4588 my $count = $artist_rs->first->cds->count;
4590 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4592 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4594 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4596 That cmp_ok() may or may not pass depending on the datasets involved. In other
4597 words the C<WHERE> condition would apply to the entire dataset, just like
4598 it would in regular SQL. If you want to add a condition only to the "right side"
4599 of a C<LEFT JOIN> - consider declaring and using a L<relationship with a custom
4600 condition|DBIx::Class::Relationship::Base/condition>
4604 =head1 DBIC BIND VALUES
4606 Because DBIC may need more information to bind values than just the column name
4607 and value itself, it uses a special format for both passing and receiving bind
4608 values. Each bind value should be composed of an arrayref of
4609 C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
4615 If present (in any form), this is what is being passed directly to bind_param.
4616 Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
4617 a single numerical type, while DBD::Pg takes a hashref if bind options.)
4619 If this is specified, all other bind options described below are ignored.
4623 If present, this is used to infer the actual bind attribute by passing to
4624 C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
4625 "data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
4627 Note that the data type is somewhat freeform (hence the sqlt_ prefix);
4628 currently drivers are expected to "Do the Right Thing" when given a common
4629 datatype name. (Not ideal, but that's what we got at this point.)
4633 Currently used to correctly allocate buffers for bind_param_inout().
4634 Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
4635 or to a sensible value based on the "data_type".
4639 Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
4640 explicitly specified they are never overridden). Also used by some weird DBDs,
4641 where the column name should be available at bind_param time (e.g. Oracle).
4645 For backwards compatibility and convenience, the following shortcuts are
4648 [ $name => $val ] === [ { dbic_colname => $name }, $val ]
4649 [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
4650 [ undef, $val ] === [ {}, $val ]
4651 $val === [ {}, $val ]
4653 =head1 AUTHOR AND CONTRIBUTORS
4655 See L<AUTHOR|DBIx::Class/AUTHOR> and L<CONTRIBUTORS|DBIx::Class/CONTRIBUTORS> in DBIx::Class
4659 You may distribute this code under the same terms as Perl itself.