1 package DBIx::Class::ResultSet;
5 use base qw/DBIx::Class/;
7 use DBIx::Class::ResultSetColumn;
8 use DBIx::Class::ResultClass::HashRefInflator;
9 use Scalar::Util qw/blessed weaken reftype/;
10 use DBIx::Class::_Util qw(
11 dbic_internal_try dump_value
12 fail_on_internal_wantarray fail_on_internal_call UNRESOLVABLE_CONDITION
16 # not importing first() as it will clash with our own method
20 # De-duplication in _merge_attr() is disabled, but left in for reference
21 # (the merger is used for other things that ought not to be de-duped)
22 *__HM_DEDUP = sub () { 0 };
32 # this is real - CDBICompat overrides it with insanity
33 # yes, prototype won't matter, but that's for now ;)
36 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class result_source/);
40 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
44 my $users_rs = $schema->resultset('User');
45 while( $user = $users_rs->next) {
46 print $user->username;
49 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
50 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
54 A ResultSet is an object which stores a set of conditions representing
55 a query. It is the backbone of DBIx::Class (i.e. the really
56 important/useful bit).
58 No SQL is executed on the database when a ResultSet is created, it
59 just stores all the conditions needed to create the query.
61 A basic ResultSet representing the data of an entire table is returned
62 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
63 L<Source|DBIx::Class::Manual::Glossary/ResultSource> name.
65 my $users_rs = $schema->resultset('User');
67 A new ResultSet is returned from calling L</search> on an existing
68 ResultSet. The new one will contain all the conditions of the
69 original, plus any new conditions added in the C<search> call.
71 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
72 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
75 The query that the ResultSet represents is B<only> executed against
76 the database when these methods are called:
77 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
79 If a resultset is used in a numeric context it returns the L</count>.
80 However, if it is used in a boolean context it is B<always> true. So if
81 you want to check if a resultset has any results, you must use C<if $rs
86 =head2 Chaining resultsets
88 Let's say you've got a query that needs to be run to return some data
89 to the user. But, you have an authorization system in place that
90 prevents certain users from seeing certain information. So, you want
91 to construct the basic query in one method, but add constraints to it in
96 my $request = $self->get_request; # Get a request object somehow.
97 my $schema = $self->result_source->schema;
99 my $cd_rs = $schema->resultset('CD')->search({
100 title => $request->param('title'),
101 year => $request->param('year'),
104 $cd_rs = $self->apply_security_policy( $cd_rs );
106 return $cd_rs->all();
109 sub apply_security_policy {
118 =head3 Resolving conditions and attributes
120 When a resultset is chained from another resultset (e.g.:
121 C<< my $new_rs = $old_rs->search(\%extra_cond, \%attrs) >>), conditions
122 and attributes with the same keys need resolving.
124 If any of L</columns>, L</select>, L</as> are present, they reset the
125 original selection, and start the selection "clean".
127 The L</join>, L</prefetch>, L</+columns>, L</+select>, L</+as> attributes
128 are merged into the existing ones from the original resultset.
130 The L</where> and L</having> attributes, and any search conditions, are
131 merged with an SQL C<AND> to the existing condition from the original
134 All other attributes are overridden by any new ones supplied in the
137 =head2 Multiple queries
139 Since a resultset just defines a query, you can do all sorts of
140 things with it with the same object.
142 # Don't hit the DB yet.
143 my $cd_rs = $schema->resultset('CD')->search({
144 title => 'something',
148 # Each of these hits the DB individually.
149 my $count = $cd_rs->count;
150 my $most_recent = $cd_rs->get_column('date_released')->max();
151 my @records = $cd_rs->all;
153 And it's not just limited to SELECT statements.
159 $cd_rs->create({ artist => 'Fred' });
161 Which is the same as:
163 $schema->resultset('CD')->create({
164 title => 'something',
169 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
171 =head2 Custom ResultSet classes
173 To add methods to your resultsets, you can subclass L<DBIx::Class::ResultSet>, similar to:
175 package MyApp::Schema::ResultSet::User;
180 use base 'DBIx::Class::ResultSet';
184 $self->search({ $self->current_source_alias . '.active' => 1 });
189 $self->search({ $self->current_source_alias . '.verified' => 0 });
192 sub created_n_days_ago {
193 my ($self, $days_ago) = @_;
195 $self->current_source_alias . '.create_date' => {
197 $self->result_source->schema->storage->datetime_parser->format_datetime(
198 DateTime->now( time_zone => 'UTC' )->subtract( days => $days_ago )
203 sub users_to_warn { shift->active->unverified->created_n_days_ago(7) }
207 See L<DBIx::Class::Schema/load_namespaces> on how DBIC can discover and
208 automatically attach L<Result|DBIx::Class::Manual::ResultClass>-specific
209 L<ResulSet|DBIx::Class::ResultSet> classes.
211 =head3 ResultSet subclassing with Moose and similar constructor-providers
213 Using L<Moose> or L<Moo> in your ResultSet classes is usually overkill, but
214 you may find it useful if your ResultSets contain a lot of business logic
215 (e.g. C<has xml_parser>, C<has json>, etc) or if you just prefer to organize
218 In order to write custom ResultSet classes with L<Moo> you need to use the
219 following template. The L<BUILDARGS|Moo/BUILDARGS> is necessary due to the
220 unusual signature of the L<constructor provided by DBIC
221 |DBIx::Class::ResultSet/new> C<< ->new($source, \%args) >>.
224 extends 'DBIx::Class::ResultSet';
225 sub BUILDARGS { $_[2] } # ::RS::new() expects my ($class, $rsrc, $args) = @_
231 If you want to build your custom ResultSet classes with L<Moose>, you need
232 a similar, though a little more elaborate template in order to interface the
233 inlining of the L<Moose>-provided
234 L<object constructor|Moose::Manual::Construction/WHERE'S THE CONSTRUCTOR?>,
237 package MyApp::Schema::ResultSet::User;
240 use MooseX::NonMoose;
241 extends 'DBIx::Class::ResultSet';
243 sub BUILDARGS { $_[2] } # ::RS::new() expects my ($class, $rsrc, $args) = @_
247 __PACKAGE__->meta->make_immutable;
251 The L<MooseX::NonMoose> is necessary so that the L<Moose> constructor does not
252 entirely overwrite the DBIC one (in contrast L<Moo> does this automatically).
253 Alternatively, you can skip L<MooseX::NonMoose> and get by with just L<Moose>
256 __PACKAGE__->meta->make_immutable(inline_constructor => 0);
264 =item Arguments: L<$source|DBIx::Class::ResultSource>, L<\%attrs?|/ATTRIBUTES>
266 =item Return Value: L<$resultset|/search>
270 The resultset constructor. Takes a source object (usually a
271 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
272 L</ATTRIBUTES> below). Does not perform any queries -- these are
273 executed as needed by the other methods.
275 Generally you never construct a resultset manually. Instead you get one
277 C<< $schema->L<resultset|DBIx::Class::Schema/resultset>('$source_name') >>
278 or C<< $another_resultset->L<search|/search>(...) >> (the later called in
281 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
287 If called on an object, proxies to L</new_result> instead, so
289 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
291 will return a CD object, not a ResultSet, and is equivalent to:
293 my $cd = $schema->resultset('CD')->new_result({ title => 'Spoon' });
295 Please also keep in mind that many internals call L</new_result> directly,
296 so overloading this method with the idea of intercepting new result object
297 creation B<will not work>. See also warning pertaining to L</create>.
307 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
308 return $class->new_result(@_);
311 my ($source, $attrs) = @_;
312 $source = $source->resolve
313 if $source->isa('DBIx::Class::ResultSourceHandle');
315 $attrs = { %{$attrs||{}} };
316 delete @{$attrs}{qw(_last_sqlmaker_alias_map _simple_passthrough_construction)};
318 if ($attrs->{page}) {
319 $attrs->{rows} ||= 10;
322 $attrs->{alias} ||= 'me';
325 result_source => $source,
326 cond => $attrs->{where},
331 # if there is a dark selector, this means we are already in a
332 # chain and the cleanup/sanification was taken care of by
334 $self->_normalize_selection($attrs)
335 unless $attrs->{_dark_selector};
338 $attrs->{result_class} || $source->result_class
348 =item Arguments: L<$cond|DBIx::Class::SQLMaker> | undef, L<\%attrs?|/ATTRIBUTES>
350 =item Return Value: $resultset (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
354 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
355 my $new_rs = $cd_rs->search({ year => 2005 });
357 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
358 # year = 2005 OR year = 2004
360 In list context, C<< ->all() >> is called implicitly on the resultset, thus
361 returning a list of L<result|DBIx::Class::Manual::ResultClass> objects instead.
362 To avoid that, use L</search_rs>.
364 If you need to pass in additional attributes but no additional condition,
365 call it as C<search(undef, \%attrs)>.
367 # "SELECT name, artistid FROM $artist_table"
368 my @all_artists = $schema->resultset('Artist')->search(undef, {
369 columns => [qw/name artistid/],
372 For a list of attributes that can be passed to C<search>, see
373 L</ATTRIBUTES>. For more examples of using this function, see
374 L<Searching|DBIx::Class::Manual::Cookbook/SEARCHING>. For a complete
375 documentation for the first argument, see L<SQL::Abstract/"WHERE CLAUSES">
376 and its extension L<DBIx::Class::SQLMaker>.
378 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
382 Note that L</search> does not process/deflate any of the values passed in the
383 L<SQL::Abstract>-compatible search condition structure. This is unlike other
384 condition-bound methods L</new_result>, L</create> and L</find>. The user must ensure
385 manually that any value passed to this method will stringify to something the
386 RDBMS knows how to deal with. A notable example is the handling of L<DateTime>
387 objects, for more info see:
388 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
394 my $rs = $self->search_rs( @_ );
397 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_WANTARRAY and my $sog = fail_on_internal_wantarray;
400 elsif (defined wantarray) {
404 # we can be called by a relationship helper, which in
405 # turn may be called in void context due to some braindead
406 # overload or whatever else the user decided to be clever
407 # at this particular day. Thus limit the exception to
408 # external code calls only
409 $self->throw_exception ('->search is *not* a mutator, calling it in void context makes no sense')
410 if (caller)[0] !~ /^\QDBIx::Class::/;
420 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
422 =item Return Value: L<$resultset|/search>
426 This method does the same exact thing as search() except it will
427 always return a resultset, even in list context.
434 my $rsrc = $self->result_source;
435 my ($call_cond, $call_attrs);
437 # Special-case handling for (undef, undef) or (undef)
438 # Note that (foo => undef) is valid deprecated syntax
439 @_ = () if not scalar grep { defined $_ } @_;
445 # fish out attrs in the ($condref, $attr) case
446 elsif (@_ == 2 and ( ! defined $_[0] or length ref $_[0] ) ) {
447 ($call_cond, $call_attrs) = @_;
450 $self->throw_exception('Odd number of arguments to search')
454 carp_unique 'search( %condition ) is deprecated, use search( \%condition ) instead'
455 unless $rsrc->result_class->isa('DBIx::Class::CDBICompat');
457 for my $i (0 .. $#_) {
459 $self->throw_exception ('All keys in condition key/value pairs must be plain scalars')
460 if (! defined $_[$i] or length ref $_[$i] );
466 # see if we can keep the cache (no $rs changes)
468 my %safe = (alias => 1, cache => 1);
469 if ( ! List::Util::first { !$safe{$_} } keys %$call_attrs and (
472 ref $call_cond eq 'HASH' && ! keys %$call_cond
474 ref $call_cond eq 'ARRAY' && ! @$call_cond
476 $cache = $self->get_cache;
479 my $old_attrs = { %{$self->{attrs}} };
480 my ($old_having, $old_where) = delete @{$old_attrs}{qw(having where)};
482 my $new_attrs = { %$old_attrs };
484 # take care of call attrs (only if anything is changing)
485 if ($call_attrs and keys %$call_attrs) {
487 # copy for _normalize_selection
488 $call_attrs = { %$call_attrs };
490 my @selector_attrs = qw/select as columns cols +select +as +columns include_columns/;
492 # reset the current selector list if new selectors are supplied
493 if (List::Util::first { exists $call_attrs->{$_} } qw/columns cols select as/) {
494 delete @{$old_attrs}{(@selector_attrs, '_dark_selector')};
497 # Normalize the new selector list (operates on the passed-in attr structure)
498 # Need to do it on every chain instead of only once on _resolved_attrs, in
499 # order to allow detection of empty vs partial 'as'
500 $call_attrs->{_dark_selector} = $old_attrs->{_dark_selector}
501 if $old_attrs->{_dark_selector};
502 $self->_normalize_selection ($call_attrs);
504 # start with blind overwriting merge, exclude selector attrs
505 $new_attrs = { %{$old_attrs}, %{$call_attrs} };
506 delete @{$new_attrs}{@selector_attrs};
508 for (@selector_attrs) {
509 $new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
510 if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
513 # older deprecated name, use only if {columns} is not there
514 if (my $c = delete $new_attrs->{cols}) {
515 carp_unique( "Resultset attribute 'cols' is deprecated, use 'columns' instead" );
516 if ($new_attrs->{columns}) {
517 carp "Resultset specifies both the 'columns' and the legacy 'cols' attributes - ignoring 'cols'";
520 $new_attrs->{columns} = $c;
525 # join/prefetch use their own crazy merging heuristics
526 foreach my $key (qw/join prefetch/) {
527 $new_attrs->{$key} = $self->_merge_joinpref_attr($old_attrs->{$key}, $call_attrs->{$key})
528 if exists $call_attrs->{$key};
531 # stack binds together
532 $new_attrs->{bind} = [ @{ $old_attrs->{bind} || [] }, @{ $call_attrs->{bind} || [] } ];
536 for ($old_where, $call_cond) {
538 $new_attrs->{where} = $self->_stack_cond (
539 $_, $new_attrs->{where}
544 if (defined $old_having) {
545 $new_attrs->{having} = $self->_stack_cond (
546 $old_having, $new_attrs->{having}
550 my $rs = (ref $self)->new($rsrc, $new_attrs);
552 $rs->set_cache($cache) if ($cache);
557 sub _normalize_selection {
558 my ($self, $attrs) = @_;
561 if ( exists $attrs->{include_columns} ) {
562 carp_unique( "Resultset attribute 'include_columns' is deprecated, use '+columns' instead" );
563 $attrs->{'+columns'} = $self->_merge_attr(
564 $attrs->{'+columns'}, delete $attrs->{include_columns}
568 # columns are always placed first, however
570 # Keep the X vs +X separation until _resolved_attrs time - this allows to
571 # delay the decision on whether to use a default select list ($rsrc->columns)
572 # allowing stuff like the remove_columns helper to work
574 # select/as +select/+as pairs need special handling - the amount of select/as
575 # elements in each pair does *not* have to be equal (think multicolumn
576 # selectors like distinct(foo, bar) ). If the selector is bare (no 'as'
577 # supplied at all) - try to infer the alias, either from the -as parameter
578 # of the selector spec, or use the parameter whole if it looks like a column
579 # name (ugly legacy heuristic). If all fails - leave the selector bare (which
580 # is ok as well), but make sure no more additions to the 'as' chain take place
581 for my $pref ('', '+') {
583 my ($sel, $as) = map {
584 my $key = "${pref}${_}";
586 my $val = [ ref $attrs->{$key} eq 'ARRAY'
588 : $attrs->{$key} || ()
590 delete $attrs->{$key};
594 if (! @$as and ! @$sel ) {
597 elsif (@$as and ! @$sel) {
598 $self->throw_exception(
599 "Unable to handle ${pref}as specification (@$as) without a corresponding ${pref}select"
603 # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
604 # if any @$as has been supplied we assume the user knows what (s)he is doing
605 # and blindly keep stacking up pieces
606 unless ($attrs->{_dark_selector}) {
609 if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
610 push @$as, $_->{-as};
612 # assume any plain no-space, no-parenthesis string to be a column spec
613 # FIXME - this is retarded but is necessary to support shit like 'count(foo)'
614 elsif ( ! ref $_ and $_ =~ /^ [^\s\(\)]+ $/x) {
617 # if all else fails - raise a flag that no more aliasing will be allowed
619 $attrs->{_dark_selector} = {
622 local $Data::Dumper::Indent = 0;
631 elsif (@$as < @$sel) {
632 $self->throw_exception(
633 "Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
636 elsif ($pref and $attrs->{_dark_selector}) {
637 $self->throw_exception(
638 "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
644 $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
645 $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
650 my ($self, $left, $right) = @_;
653 (ref $_ eq 'ARRAY' and !@$_)
655 (ref $_ eq 'HASH' and ! keys %$_)
656 ) and $_ = undef for ($left, $right);
658 # either one of the two undef
659 if ( (defined $left) xor (defined $right) ) {
660 return defined $left ? $left : $right;
663 elsif ( ! defined $left ) {
667 return $self->result_source->schema->storage->_collapse_cond({ -and => [$left, $right] });
671 =head2 search_literal
673 B<CAVEAT>: C<search_literal> is provided for Class::DBI compatibility and
674 should only be used in that context. C<search_literal> is a convenience
675 method. It is equivalent to calling C<< $schema->search(\[]) >>, but if you
676 want to ensure columns are bound correctly, use L</search>.
678 See L<DBIx::Class::Manual::Cookbook/SEARCHING> and
679 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
680 require C<search_literal>.
684 =item Arguments: $sql_fragment, @standalone_bind_values
686 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
690 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
691 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
693 Pass a literal chunk of SQL to be added to the conditional part of the
696 Example of how to use C<search> instead of C<search_literal>
698 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
699 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
704 my ($self, $sql, @bind) = @_;
706 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
709 return $self->search(\[ $sql, map [ {} => $_ ], @bind ], ($attr || () ));
716 =item Arguments: \%columns_values | @pk_values, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
718 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
722 Finds and returns a single row based on supplied criteria. Takes either a
723 hashref with the same format as L</create> (including inference of foreign
724 keys from related objects), or a list of primary key values in the same
725 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
726 declaration on the L</result_source>.
728 In either case an attempt is made to combine conditions already existing on
729 the resultset with the condition passed to this method.
731 To aid with preparing the correct query for the storage you may supply the
732 C<key> attribute, which is the name of a
733 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
734 unique constraint corresponding to the
735 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
736 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
737 to construct a query that satisfies the named unique constraint fully (
738 non-NULL values for each column member of the constraint) an exception is
741 If no C<key> is specified, the search is carried over all unique constraints
742 which are fully defined by the available condition.
744 If no such constraint is found, C<find> currently defaults to a simple
745 C<< search->(\%column_values) >> which may or may not do what you expect.
746 Note that this fallback behavior may be deprecated in further versions. If
747 you need to search with arbitrary conditions - use L</search>. If the query
748 resulting from this fallback produces more than one row, a warning to the
749 effect is issued, though only the first row is constructed and returned as
752 In addition to C<key>, L</find> recognizes and applies standard
753 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
755 Note that if you have extra concerns about the correctness of the resulting
756 query you need to specify the C<key> attribute and supply the entire condition
757 as an argument to find (since it is not always possible to perform the
758 combination of the resultset condition with the supplied one, especially if
759 the resultset condition contains literal sql).
761 For example, to find a row by its primary key:
763 my $cd = $schema->resultset('CD')->find(5);
765 You can also find a row by a specific unique constraint:
767 my $cd = $schema->resultset('CD')->find(
769 artist => 'Massive Attack',
770 title => 'Mezzanine',
772 { key => 'cd_artist_title' }
775 See also L</find_or_create> and L</update_or_create>.
781 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
783 my $rsrc = $self->result_source;
786 if (exists $attrs->{key}) {
787 $constraint_name = defined $attrs->{key}
789 : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
793 # Parse out the condition from input
796 if (ref $_[0] eq 'HASH') {
797 $call_cond = { %{$_[0]} };
800 # if only values are supplied we need to default to 'primary'
801 $constraint_name = 'primary' unless defined $constraint_name;
803 my @c_cols = $rsrc->unique_constraint_columns($constraint_name);
805 $self->throw_exception(
806 "No constraint columns, maybe a malformed '$constraint_name' constraint?"
809 $self->throw_exception (
810 'find() expects either a column/value hashref, or a list of values '
811 . "corresponding to the columns of the specified unique constraint '$constraint_name'"
812 ) unless @c_cols == @_;
814 @{$call_cond}{@c_cols} = @_;
817 # process relationship data if any
818 for my $key (keys %$call_cond) {
820 length ref($call_cond->{$key})
822 my $relinfo = $rsrc->relationship_info($key)
824 # implicitly skip has_many's (likely MC)
825 (ref (my $val = delete $call_cond->{$key}) ne 'ARRAY' )
827 my ($rel_cond, $crosstable) = $rsrc->_resolve_condition(
828 $relinfo->{cond}, $val, $key, $key
831 $self->throw_exception("Complex condition via relationship '$key' is unsupported in find()")
832 if $crosstable or ref($rel_cond) ne 'HASH';
834 # supplement condition
835 # relationship conditions take precedence (?)
836 @{$call_cond}{keys %$rel_cond} = values %$rel_cond;
840 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
842 if (defined $constraint_name) {
843 $final_cond = $self->_qualify_cond_columns (
845 $self->result_source->_minimal_valueset_satisfying_constraint(
846 constraint_name => $constraint_name,
847 values => ($self->_merge_with_rscond($call_cond))[0],
854 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
855 # This means that we got here after a merger of relationship conditions
856 # in ::Relationship::Base::search_related (the row method), and furthermore
857 # the relationship is of the 'single' type. This means that the condition
858 # provided by the relationship (already attached to $self) is sufficient,
859 # as there can be only one row in the database that would satisfy the
863 my (@unique_queries, %seen_column_combinations, $ci, @fc_exceptions);
865 # no key was specified - fall down to heuristics mode:
866 # run through all unique queries registered on the resultset, and
867 # 'OR' all qualifying queries together
869 # always start from 'primary' if it exists at all
870 for my $c_name ( sort {
872 : $b eq 'primary' ? 1
874 } $rsrc->unique_constraint_names) {
876 next if $seen_column_combinations{
877 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
881 push @unique_queries, $self->_qualify_cond_columns(
882 $self->result_source->_minimal_valueset_satisfying_constraint(
883 constraint_name => $c_name,
884 values => ($self->_merge_with_rscond($call_cond))[0],
885 columns_info => ($ci ||= $self->result_source->columns_info),
891 push @fc_exceptions, $_ if $_ =~ /\bFilterColumn\b/;
896 @unique_queries ? \@unique_queries
897 : @fc_exceptions ? $self->throw_exception(join "; ", map { $_ =~ /(.*) at .+ line \d+$/s } @fc_exceptions )
898 : $self->_non_unique_find_fallback ($call_cond, $attrs)
902 # Run the query, passing the result_class since it should propagate for find
903 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
904 if ($rs->_resolved_attrs->{collapse}) {
906 carp "Query returned more than one row" if $rs->next;
914 # This is a stop-gap method as agreed during the discussion on find() cleanup:
915 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
917 # It is invoked when find() is called in legacy-mode with insufficiently-unique
918 # condition. It is provided for overrides until a saner way forward is devised
920 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
921 # the road. Please adjust your tests accordingly to catch this situation early
922 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
924 # The method will not be removed without an adequately complete replacement
925 # for strict-mode enforcement
926 sub _non_unique_find_fallback {
927 my ($self, $cond, $attrs) = @_;
929 return $self->_qualify_cond_columns(
931 exists $attrs->{alias}
933 : $self->{attrs}{alias}
938 sub _qualify_cond_columns {
939 my ($self, $cond, $alias) = @_;
941 my %aliased = %$cond;
942 for (keys %aliased) {
943 $aliased{"$alias.$_"} = delete $aliased{$_}
950 sub _build_unique_cond {
952 '_build_unique_cond is a private method, and moreover is about to go '
953 . 'away. Please contact the development team at %s if you believe you '
954 . 'have a genuine use for this method, in order to discuss alternatives.',
955 DBIx::Class::_ENV_::HELP_URL,
958 my ($self, $constraint_name, $cond, $croak_on_null) = @_;
960 $self->result_source->_minimal_valueset_satisfying_constraint(
961 constraint_name => $constraint_name,
963 carp_on_nulls => !$croak_on_null
967 =head2 search_related
971 =item Arguments: $rel_name, $cond?, L<\%attrs?|/ATTRIBUTES>
973 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
977 $new_rs = $cd_rs->search_related('artist', {
981 Searches the specified relationship, optionally specifying a condition and
982 attributes for matching records. See L</ATTRIBUTES> for more information.
984 In list context, C<< ->all() >> is called implicitly on the resultset, thus
985 returning a list of result objects instead. To avoid that, use L</search_related_rs>.
987 See also L</search_related_rs>.
992 return shift->related_resultset(shift)->search(@_);
995 =head2 search_related_rs
997 This method works exactly the same as search_related, except that
998 it guarantees a resultset, even in list context.
1002 sub search_related_rs {
1003 return shift->related_resultset(shift)->search_rs(@_);
1010 =item Arguments: none
1012 =item Return Value: L<$cursor|DBIx::Class::Cursor>
1016 Returns a storage-driven cursor to the given resultset. See
1017 L<DBIx::Class::Cursor> for more information.
1024 return $self->{cursor} ||= do {
1025 my $attrs = $self->_resolved_attrs;
1026 $self->result_source->storage->select(
1027 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
1036 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1038 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1042 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1044 Inflates the first result without creating a cursor if the resultset has
1045 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1048 While this method can take an optional search condition (just like L</search>)
1049 being a fast-code-path it does not recognize search attributes. If you need to
1050 add extra joins or similar, call L</search> and then chain-call L</single> on the
1051 L<DBIx::Class::ResultSet> returned.
1057 As of 0.08100, this method enforces the assumption that the preceding
1058 query returns only one row. If more than one row is returned, you will receive
1061 Query returned more than one row
1063 In this case, you should be using L</next> or L</find> instead, or if you really
1064 know what you are doing, use the L</rows> attribute to explicitly limit the size
1067 This method will also throw an exception if it is called on a resultset prefetching
1068 has_many, as such a prefetch implies fetching multiple rows from the database in
1069 order to assemble the resulting object.
1076 my ($self, $where) = @_;
1078 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1081 my $attrs = { %{$self->_resolved_attrs} };
1083 $self->throw_exception(
1084 'single() can not be used on resultsets collapsing a has_many. Use find( \%cond ) or next() instead'
1085 ) if $attrs->{collapse};
1088 if (defined $attrs->{where}) {
1091 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1092 $where, delete $attrs->{where} ]
1095 $attrs->{where} = $where;
1099 my $data = [ $self->result_source->storage->select_single(
1100 $attrs->{from}, $attrs->{select},
1101 $attrs->{where}, $attrs
1104 return undef unless @$data;
1105 $self->{_stashed_rows} = [ $data ];
1106 $self->_construct_results->[0];
1113 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1115 =item Return Value: L<$resultsetcolumn|DBIx::Class::ResultSetColumn>
1119 my $max_length = $rs->get_column('length')->max;
1121 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1126 my ($self, $column) = @_;
1127 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
1135 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1137 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1141 # WHERE title LIKE '%blue%'
1142 $cd_rs = $rs->search_like({ title => '%blue%'});
1144 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1145 that this is simply a convenience method retained for ex Class::DBI users.
1146 You most likely want to use L</search> with specific operators.
1148 For more information, see L<DBIx::Class::Manual::Cookbook>.
1150 This method is deprecated and will be removed in 0.09. Use L<search()|/search>
1151 instead. An example conversion is:
1153 ->search_like({ foo => 'bar' });
1157 ->search({ foo => { like => 'bar' } });
1164 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1165 .' Instead use ->search({ x => { -like => "y%" } })'
1166 .' (note the outer pair of {}s - they are important!)'
1168 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1169 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1170 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1171 return $class->search($query, { %$attrs });
1178 =item Arguments: $first, $last
1180 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1184 Returns a resultset or object list representing a subset of elements from the
1185 resultset slice is called on. Indexes are from 0, i.e., to get the first
1186 three records, call:
1188 my ($one, $two, $three) = $rs->slice(0, 2);
1193 my ($self, $min, $max) = @_;
1194 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1195 $attrs->{offset} = $self->{attrs}{offset} || 0;
1196 $attrs->{offset} += $min;
1197 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1198 return $self->search(undef, $attrs);
1205 =item Arguments: none
1207 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1211 Returns the next element in the resultset (C<undef> is there is none).
1213 Can be used to efficiently iterate over records in the resultset:
1215 my $rs = $schema->resultset('CD')->search;
1216 while (my $cd = $rs->next) {
1220 Note that you need to store the resultset object, and call C<next> on it.
1221 Calling C<< resultset('Table')->next >> repeatedly will always return the
1222 first record from the resultset.
1229 if (my $cache = $self->get_cache) {
1230 $self->{all_cache_position} ||= 0;
1231 return $cache->[$self->{all_cache_position}++];
1234 if ($self->{attrs}{cache}) {
1235 delete $self->{pager};
1236 $self->{all_cache_position} = 1;
1237 return ($self->all)[0];
1240 return shift(@{$self->{_stashed_results}}) if @{ $self->{_stashed_results}||[] };
1242 $self->{_stashed_results} = $self->_construct_results
1245 return shift @{$self->{_stashed_results}};
1248 # Constructs as many results as it can in one pass while respecting
1249 # cursor laziness. Several modes of operation:
1251 # * Always builds everything present in @{$self->{_stashed_rows}}
1252 # * If called with $fetch_all true - pulls everything off the cursor and
1253 # builds all result structures (or objects) in one pass
1254 # * If $self->_resolved_attrs->{collapse} is true, checks the order_by
1255 # and if the resultset is ordered properly by the left side:
1256 # * Fetches stuff off the cursor until the "master object" changes,
1257 # and saves the last extra row (if any) in @{$self->{_stashed_rows}}
1259 # * Just fetches, and collapses/constructs everything as if $fetch_all
1260 # was requested (there is no other way to collapse except for an
1262 # * If no collapse is requested - just get the next row, construct and
1264 sub _construct_results {
1265 my ($self, $fetch_all) = @_;
1267 my $rsrc = $self->result_source;
1268 my $attrs = $self->_resolved_attrs;
1273 ! $attrs->{order_by}
1277 my @pcols = $rsrc->primary_columns
1279 # default order for collapsing unless the user asked for something
1280 $attrs->{order_by} = [ map { join '.', $attrs->{alias}, $_} @pcols ];
1281 $attrs->{_ordered_for_collapse} = 1;
1282 $attrs->{_order_is_artificial} = 1;
1285 # this will be used as both initial raw-row collector AND as a RV of
1286 # _construct_results. Not regrowing the array twice matters a lot...
1287 # a surprising amount actually
1288 my $rows = delete $self->{_stashed_rows};
1290 my $cursor; # we may not need one at all
1292 my $did_fetch_all = $fetch_all;
1295 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1296 $rows = [ ($rows ? @$rows : ()), $self->cursor->all ];
1298 elsif( $attrs->{collapse} ) {
1300 # a cursor will need to be closed over in case of collapse
1301 $cursor = $self->cursor;
1303 $attrs->{_ordered_for_collapse} = (
1309 ->_extract_colinfo_of_stable_main_source_order_by_portion($attrs)
1311 ) unless defined $attrs->{_ordered_for_collapse};
1313 if (! $attrs->{_ordered_for_collapse}) {
1316 # instead of looping over ->next, use ->all in stealth mode
1317 # *without* calling a ->reset afterwards
1318 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1319 if (! $cursor->{_done}) {
1320 $rows = [ ($rows ? @$rows : ()), $cursor->all ];
1321 $cursor->{_done} = 1;
1326 if (! $did_fetch_all and ! @{$rows||[]} ) {
1327 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1328 $cursor ||= $self->cursor;
1329 if (scalar (my @r = $cursor->next) ) {
1334 return undef unless @{$rows||[]};
1336 # sanity check - people are too clever for their own good
1337 if ($attrs->{collapse} and my $aliastypes = $attrs->{_last_sqlmaker_alias_map} ) {
1339 my $multiplied_selectors;
1340 for my $sel_alias ( grep { $_ ne $attrs->{alias} } keys %{ $aliastypes->{selecting} } ) {
1342 $aliastypes->{multiplying}{$sel_alias}
1344 $aliastypes->{premultiplied}{$sel_alias}
1346 $multiplied_selectors->{$_} = 1 for values %{$aliastypes->{selecting}{$sel_alias}{-seen_columns}}
1350 for my $i (0 .. $#{$attrs->{as}} ) {
1351 my $sel = $attrs->{select}[$i];
1353 if (ref $sel eq 'SCALAR') {
1356 elsif( ref $sel eq 'REF' and ref $$sel eq 'ARRAY' ) {
1360 $self->throw_exception(
1361 'Result collapse not possible - selection from a has_many source redirected to the main object'
1362 ) if ($multiplied_selectors->{$sel} and $attrs->{as}[$i] !~ /\./);
1366 # hotspot - skip the setter
1367 my $res_class = $self->_result_class;
1369 my $inflator_cref = $self->{_result_inflator}{cref} ||= do {
1370 $res_class->can ('inflate_result')
1371 or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
1374 my $infmap = $attrs->{as};
1376 $self->{_result_inflator}{is_core_row} = ( (
1379 ( \&DBIx::Class::Row::inflate_result || die "No ::Row::inflate_result() - can't happen" )
1380 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_core_row};
1382 $self->{_result_inflator}{is_hri} = ( (
1383 ! $self->{_result_inflator}{is_core_row}
1385 $inflator_cref == \&DBIx::Class::ResultClass::HashRefInflator::inflate_result
1386 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_hri};
1389 if ($attrs->{_simple_passthrough_construction}) {
1390 # construct a much simpler array->hash folder for the one-table HRI cases right here
1391 if ($self->{_result_inflator}{is_hri}) {
1392 for my $r (@$rows) {
1393 $r = { map { $infmap->[$_] => $r->[$_] } 0..$#$infmap };
1396 # FIXME SUBOPTIMAL this is a very very very hot spot
1397 # while rather optimal we can *still* do much better, by
1398 # building a smarter Row::inflate_result(), and
1399 # switch to feeding it data via a much leaner interface
1401 # crude unscientific benchmarking indicated the shortcut eval is not worth it for
1402 # this particular resultset size
1403 elsif ( $self->{_result_inflator}{is_core_row} and @$rows < 60 ) {
1404 for my $r (@$rows) {
1405 $r = $inflator_cref->($res_class, $rsrc, { map { $infmap->[$_] => $r->[$_] } (0..$#$infmap) } );
1410 ( $self->{_result_inflator}{is_core_row}
1411 ? '$_ = $inflator_cref->($res_class, $rsrc, { %s }) for @$rows'
1412 # a custom inflator may be a multiplier/reductor - put it in direct list ctx
1413 : '@$rows = map { $inflator_cref->($res_class, $rsrc, { %s } ) } @$rows'
1415 ( join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap ) )
1421 $self->{_result_inflator}{is_hri} ? 'hri'
1422 : $self->{_result_inflator}{is_core_row} ? 'classic_pruning'
1423 : 'classic_nonpruning'
1426 # $args and $attrs to _mk_row_parser are separated to delineate what is
1427 # core collapser stuff and what is dbic $rs specific
1428 $self->{_row_parser}{$parser_type}{cref} = $rsrc->_mk_row_parser({
1430 inflate_map => $infmap,
1431 collapse => $attrs->{collapse},
1432 premultiplied => $attrs->{_main_source_premultiplied},
1433 hri_style => $self->{_result_inflator}{is_hri},
1434 prune_null_branches => $self->{_result_inflator}{is_hri} || $self->{_result_inflator}{is_core_row},
1435 }, $attrs) unless $self->{_row_parser}{$parser_type}{cref};
1437 my $next_cref = ($did_fetch_all or ! $attrs->{collapse})
1440 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1441 my @r = $cursor->next or return;
1446 $self->{_row_parser}{$parser_type}{cref}->(
1449 ( $self->{_stashed_rows} = [] ),
1450 ( my $null_violations = {} ),
1453 $self->throw_exception(
1454 'Collapse aborted - the following columns are declared (or defaulted to) '
1455 . 'non-nullable within DBIC but NULLs were retrieved from storage: '
1456 . join( ', ', map { "'$infmap->[$_]'" } sort { $a <=> $b } keys %$null_violations )
1457 . ' within data row ' . dump_value({
1460 ( ! defined $self->{_stashed_rows}[0][$_] or length $self->{_stashed_rows}[0][$_] < 50 )
1461 ? $self->{_stashed_rows}[0][$_]
1462 : substr( $self->{_stashed_rows}[0][$_], 0, 50 ) . '...'
1463 } 0 .. $#{$self->{_stashed_rows}[0]}
1465 ) if keys %$null_violations;
1467 # simple in-place substitution, does not regrow $rows
1468 if ($self->{_result_inflator}{is_core_row}) {
1469 $_ = $inflator_cref->($res_class, $rsrc, @$_) for @$rows
1471 # Special-case multi-object HRI - there is no $inflator_cref pass at all
1472 elsif ( ! $self->{_result_inflator}{is_hri} ) {
1473 # the inflator may be a multiplier/reductor - put it in list ctx
1474 @$rows = map { $inflator_cref->($res_class, $rsrc, @$_) } @$rows;
1478 # The @$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: $result_class
1514 An accessor for the class to use when creating result objects. Defaults to
1515 C<< result_source->result_class >> - which in most cases is the name of the
1516 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1518 Note that changing the result_class will also remove any components
1519 that were originally loaded in the source class via
1520 L<load_components|Class::C3::Componentised/load_components( @comps )>.
1521 Any overloaded methods in the original source class will not run.
1526 my ($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;
1973 for my $row ($subrs->cursor->all) {
1975 { $idcols->[$_] => $row->[$_] }
1982 my $res = $cond ? $storage->$op (
1984 $op eq 'update' ? $values : (),
1988 $guard->commit if $guard;
1997 =item Arguments: \%values
1999 =item Return Value: $underlying_storage_rv
2003 Sets the specified columns in the resultset to the supplied values in a
2004 single query. Note that this will not run any accessor/set_column/update
2005 triggers, nor will it update any result object instances derived from this
2006 resultset (this includes the contents of the L<resultset cache|/set_cache>
2007 if any). See L</update_all> if you need to execute any on-update
2008 triggers or cascades defined either by you or a
2009 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2011 The return value is a pass through of what the underlying
2012 storage backend returned, and may vary. See L<DBI/execute> for the most
2017 Note that L</update> does not process/deflate any of the values passed in.
2018 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
2019 ensure manually that any value passed to this method will stringify to
2020 something the RDBMS knows how to deal with. A notable example is the
2021 handling of L<DateTime> objects, for more info see:
2022 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
2027 my ($self, $values) = @_;
2028 $self->throw_exception('Values for update must be a hash')
2029 unless ref $values eq 'HASH';
2031 return $self->_rs_update_delete ('update', $values);
2038 =item Arguments: \%values
2040 =item Return Value: 1
2044 Fetches all objects and updates them one at a time via
2045 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
2046 triggers, while L</update> will not.
2051 my ($self, $values) = @_;
2052 $self->throw_exception('Values for update_all must be a hash')
2053 unless ref $values eq 'HASH';
2055 my $guard = $self->result_source->schema->txn_scope_guard;
2056 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
2065 =item Arguments: none
2067 =item Return Value: $underlying_storage_rv
2071 Deletes the rows matching this resultset in a single query. Note that this
2072 will not run any delete triggers, nor will it alter the
2073 L<in_storage|DBIx::Class::Row/in_storage> status of any result object instances
2074 derived from this resultset (this includes the contents of the
2075 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
2076 execute any on-delete triggers or cascades defined either by you or a
2077 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2079 The return value is a pass through of what the underlying storage backend
2080 returned, and may vary. See L<DBI/execute> for the most common case.
2086 $self->throw_exception('delete does not accept any arguments')
2089 return $self->_rs_update_delete ('delete');
2096 =item Arguments: none
2098 =item Return Value: 1
2102 Fetches all objects and deletes them one at a time via
2103 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2104 triggers, while L</delete> will not.
2110 $self->throw_exception('delete_all does not accept any arguments')
2113 my $guard = $self->result_source->schema->txn_scope_guard;
2114 $_->delete for $self->all;
2123 =item Arguments: [ \@column_list, \@row_values+ ] | [ \%col_data+ ]
2125 =item Return Value: L<\@result_objects|DBIx::Class::Manual::ResultClass> (scalar context) | L<@result_objects|DBIx::Class::Manual::ResultClass> (list context)
2129 Accepts either an arrayref of hashrefs or alternatively an arrayref of
2136 The context of this method call has an important effect on what is
2137 submitted to storage. In void context data is fed directly to fastpath
2138 insertion routines provided by the underlying storage (most often
2139 L<DBI/execute_for_fetch>), bypassing the L<new|DBIx::Class::Row/new> and
2140 L<insert|DBIx::Class::Row/insert> calls on the
2141 L<Result|DBIx::Class::Manual::ResultClass> class, including any
2142 augmentation of these methods provided by components. For example if you
2143 are using something like L<DBIx::Class::UUIDColumns> to create primary
2144 keys for you, you will find that your PKs are empty. In this case you
2145 will have to explicitly force scalar or list context in order to create
2150 In non-void (scalar or list) context, this method is simply a wrapper
2151 for L</create>. Depending on list or scalar context either a list of
2152 L<Result|DBIx::Class::Manual::ResultClass> objects or an arrayref
2153 containing these objects is returned.
2155 When supplying data in "arrayref of arrayrefs" invocation style, the
2156 first element should be a list of column names and each subsequent
2157 element should be a data value in the earlier specified column order.
2160 $schema->resultset("Artist")->populate([
2161 [ qw( artistid name ) ],
2162 [ 100, 'A Formally Unknown Singer' ],
2163 [ 101, 'A singer that jumped the shark two albums ago' ],
2164 [ 102, 'An actually cool singer' ],
2167 For the arrayref of hashrefs style each hashref should be a structure
2168 suitable for passing to L</create>. Multi-create is also permitted with
2171 $schema->resultset("Artist")->populate([
2172 { artistid => 4, name => 'Manufactured Crap', cds => [
2173 { title => 'My First CD', year => 2006 },
2174 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2177 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2178 { title => 'My parents sold me to a record company', year => 2005 },
2179 { title => 'Why Am I So Ugly?', year => 2006 },
2180 { title => 'I Got Surgery and am now Popular', year => 2007 }
2185 If you attempt a void-context multi-create as in the example above (each
2186 Artist also has the related list of CDs), and B<do not> supply the
2187 necessary autoinc foreign key information, this method will proxy to the
2188 less efficient L</create>, and then throw the Result objects away. In this
2189 case there are obviously no benefits to using this method over L</create>.
2196 # this is naive and just a quick check
2197 # the types will need to be checked more thoroughly when the
2198 # multi-source populate gets added
2200 ref $_[0] eq 'ARRAY'
2202 ( @{$_[0]} or return )
2204 ( ref $_[0][0] eq 'HASH' or ref $_[0][0] eq 'ARRAY' )
2207 ) or $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2209 # FIXME - no cref handling
2210 # At this point assume either hashes or arrays
2212 if(defined wantarray) {
2213 my (@results, $guard);
2215 if (ref $data->[0] eq 'ARRAY') {
2216 # column names only, nothing to do
2217 return if @$data == 1;
2219 $guard = $self->result_source->schema->storage->txn_scope_guard
2223 { my $vals = $_; $self->new_result({ map { $data->[0][$_] => $vals->[$_] } 0..$#{$data->[0]} })->insert }
2224 @{$data}[1 .. $#$data]
2229 $guard = $self->result_source->schema->storage->txn_scope_guard
2232 @results = map { $self->new_result($_)->insert } @$data;
2235 $guard->commit if $guard;
2236 return wantarray ? @results : \@results;
2239 # we have to deal with *possibly incomplete* related data
2240 # this means we have to walk the data structure twice
2241 # whether we want this or not
2242 # jnap, I hate you ;)
2243 my $rsrc = $self->result_source;
2244 my $rel_info = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2246 my ($colinfo, $colnames, $slices_with_rels);
2250 for my $i (0 .. $#$data) {
2252 my $current_slice_seen_rel_infos;
2254 ### Determine/Supplement collists
2255 ### BEWARE - This is a hot piece of code, a lot of weird idioms were used
2256 if( ref $data->[$i] eq 'ARRAY' ) {
2258 # positional(!) explicit column list
2260 # column names only, nothing to do
2261 return if @$data == 1;
2263 $colinfo->{$data->[0][$_]} = { pos => $_, name => $data->[0][$_] } and push @$colnames, $data->[0][$_]
2264 for 0 .. $#{$data->[0]};
2271 for (values %$colinfo) {
2272 if ($_->{is_rel} ||= (
2273 $rel_info->{$_->{name}}
2276 ref $data->[$i][$_->{pos}] eq 'ARRAY'
2278 ref $data->[$i][$_->{pos}] eq 'HASH'
2280 ( defined blessed $data->[$i][$_->{pos}] and $data->[$i][$_->{pos}]->isa('DBIx::Class::Row') )
2286 # moar sanity check... sigh
2287 for ( ref $data->[$i][$_->{pos}] eq 'ARRAY' ? @{$data->[$i][$_->{pos}]} : $data->[$i][$_->{pos}] ) {
2288 if ( defined blessed $_ and $_->isa('DBIx::Class::Row' ) ) {
2289 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2290 return my $throwaway = $self->populate(@_);
2294 push @$current_slice_seen_rel_infos, $rel_info->{$_->{name}};
2299 if ($current_slice_seen_rel_infos) {
2300 push @$slices_with_rels, { map { $colnames->[$_] => $data->[$i][$_] } 0 .. $#$colnames };
2302 # this is needed further down to decide whether or not to fallback to create()
2303 $colinfo->{$colnames->[$_]}{seen_null} ||= ! defined $data->[$i][$_]
2304 for 0 .. $#$colnames;
2307 elsif( ref $data->[$i] eq 'HASH' ) {
2309 for ( sort keys %{$data->[$i]} ) {
2311 $colinfo->{$_} ||= do {
2313 $self->throw_exception("Column '$_' must be present in supplied explicit column list")
2314 if $data_start; # it will be 0 on AoH, 1 on AoA
2316 push @$colnames, $_;
2319 { pos => $#$colnames, name => $_ }
2322 if ($colinfo->{$_}{is_rel} ||= (
2326 ref $data->[$i]{$_} eq 'ARRAY'
2328 ref $data->[$i]{$_} eq 'HASH'
2330 ( defined blessed $data->[$i]{$_} and $data->[$i]{$_}->isa('DBIx::Class::Row') )
2336 # moar sanity check... sigh
2337 for ( ref $data->[$i]{$_} eq 'ARRAY' ? @{$data->[$i]{$_}} : $data->[$i]{$_} ) {
2338 if ( defined blessed $_ and $_->isa('DBIx::Class::Row' ) ) {
2339 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2340 return my $throwaway = $self->populate(@_);
2344 push @$current_slice_seen_rel_infos, $rel_info->{$_};
2348 if ($current_slice_seen_rel_infos) {
2349 push @$slices_with_rels, $data->[$i];
2351 # this is needed further down to decide whether or not to fallback to create()
2352 $colinfo->{$_}{seen_null} ||= ! defined $data->[$i]{$_}
2353 for keys %{$data->[$i]};
2357 $self->throw_exception('Unexpected populate() data structure member type: ' . ref $data->[$i] );
2361 { $_->{attrs}{is_depends_on} }
2362 @{ $current_slice_seen_rel_infos || [] }
2364 carp_unique("Fast-path populate() of belongs_to relationship data is not possible - falling back to regular create()");
2365 return my $throwaway = $self->populate(@_);
2369 if( $slices_with_rels ) {
2371 # need to exclude the rel "columns"
2372 $colnames = [ grep { ! $colinfo->{$_}{is_rel} } @$colnames ];
2374 # extra sanity check - ensure the main source is in fact identifiable
2375 # the localizing of nullability is insane, but oh well... the use-case is legit
2376 my $ci = $rsrc->columns_info($colnames);
2378 $ci->{$_} = { %{$ci->{$_}}, is_nullable => 0 }
2379 for grep { ! $colinfo->{$_}{seen_null} } keys %$ci;
2381 unless( $rsrc->_identifying_column_set($ci) ) {
2382 carp_unique("Fast-path populate() of non-uniquely identifiable rows with related data is not possible - falling back to regular create()");
2383 return my $throwaway = $self->populate(@_);
2387 ### inherit the data locked in the conditions of the resultset
2388 my ($rs_data) = $self->_merge_with_rscond({});
2389 delete @{$rs_data}{@$colnames}; # passed-in stuff takes precedence
2391 # if anything left - decompose rs_data
2393 if (keys %$rs_data) {
2394 push @$rs_data_vals, $rs_data->{$_}
2395 for sort keys %$rs_data;
2400 $guard = $rsrc->schema->storage->txn_scope_guard
2401 if $slices_with_rels;
2403 ### main source data
2404 # FIXME - need to switch entirely to a coderef-based thing,
2405 # so that large sets aren't copied several times... I think
2406 $rsrc->storage->_insert_bulk(
2408 [ @$colnames, sort keys %$rs_data ],
2410 ref $data->[$_] eq 'ARRAY'
2412 $slices_with_rels ? [ @{$data->[$_]}[0..$#$colnames], @{$rs_data_vals||[]} ] # the collist changed
2413 : $rs_data_vals ? [ @{$data->[$_]}, @$rs_data_vals ]
2416 : [ @{$data->[$_]}{@$colnames}, @{$rs_data_vals||[]} ]
2417 } $data_start .. $#$data ],
2420 ### do the children relationships
2421 if ( $slices_with_rels ) {
2422 my @rels = grep { $colinfo->{$_}{is_rel} } keys %$colinfo
2423 or die 'wtf... please report a bug with DBIC_TRACE=1 output (stacktrace)';
2425 for my $sl (@$slices_with_rels) {
2427 my ($main_proto, $main_proto_rs);
2428 for my $rel (@rels) {
2429 next unless defined $sl->{$rel};
2433 (map { $_ => $sl->{$_} } @$colnames),
2436 unless (defined $colinfo->{$rel}{rs}) {
2438 $colinfo->{$rel}{rs} = $rsrc->related_source($rel)->resultset;
2440 $colinfo->{$rel}{fk_map} = { reverse %{ $rsrc->_resolve_relationship_condition(
2442 self_alias => "\xFE", # irrelevant
2443 foreign_alias => "\xFF", # irrelevant
2444 )->{identity_map} || {} } };
2448 $colinfo->{$rel}{rs}->search({ map # only so that we inherit them values properly, no actual search
2451 ( $main_proto_rs ||= $rsrc->resultset->search($main_proto) )
2452 ->get_column( $colinfo->{$rel}{fk_map}{$_} )
2456 keys %{$colinfo->{$rel}{fk_map}}
2457 })->populate( ref $sl->{$rel} eq 'ARRAY' ? $sl->{$rel} : [ $sl->{$rel} ] );
2464 $guard->commit if $guard;
2471 =item Arguments: none
2473 =item Return Value: L<$pager|Data::Page>
2477 Returns a L<Data::Page> object for the current resultset. Only makes
2478 sense for queries with a C<page> attribute.
2480 To get the full count of entries for a paged resultset, call
2481 C<total_entries> on the L<Data::Page> object.
2488 return $self->{pager} if $self->{pager};
2490 my $attrs = $self->{attrs};
2491 if (!defined $attrs->{page}) {
2492 $self->throw_exception("Can't create pager for non-paged rs");
2494 elsif ($attrs->{page} <= 0) {
2495 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2497 $attrs->{rows} ||= 10;
2499 # throw away the paging flags and re-run the count (possibly
2500 # with a subselect) to get the real total count
2501 my $count_attrs = { %$attrs };
2502 delete @{$count_attrs}{qw/rows offset page pager/};
2504 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2506 require DBIx::Class::ResultSet::Pager;
2507 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2508 sub { $total_rs->count }, #lazy-get the total
2510 $self->{attrs}{page},
2518 =item Arguments: $page_number
2520 =item Return Value: L<$resultset|/search>
2524 Returns a resultset for the $page_number page of the resultset on which page
2525 is called, where each page contains a number of rows equal to the 'rows'
2526 attribute set on the resultset (10 by default).
2531 my ($self, $page) = @_;
2532 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2539 =item Arguments: \%col_data
2541 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2545 Creates a new result object in the resultset's result class and returns
2546 it. The row is not inserted into the database at this point, call
2547 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2548 will tell you whether the result object has been inserted or not.
2550 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2555 my ($self, $values) = @_;
2557 $self->throw_exception( "new_result takes only one argument - a hashref of values" )
2560 $self->throw_exception( "Result object instantiation requires a hashref as argument" )
2561 unless (ref $values eq 'HASH');
2563 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2565 my $new = $self->result_class->new({
2567 ( @$cols_from_relations
2568 ? (-cols_from_relations => $cols_from_relations)
2571 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2575 reftype($new) eq 'HASH'
2581 carp_unique (sprintf (
2582 "%s->new returned a blessed empty hashref - a strong indicator something is wrong with its inheritance chain",
2583 $self->result_class,
2590 # _merge_with_rscond
2592 # Takes a simple hash of K/V data and returns its copy merged with the
2593 # condition already present on the resultset. Additionally returns an
2594 # arrayref of value/condition names, which were inferred from related
2595 # objects (this is needed for in-memory related objects)
2596 sub _merge_with_rscond {
2597 my ($self, $data) = @_;
2599 my ($implied_data, @cols_from_relations);
2601 my $alias = $self->{attrs}{alias};
2603 if (! defined $self->{cond}) {
2604 # just massage $data below
2606 elsif ($self->{cond} eq UNRESOLVABLE_CONDITION) {
2607 $implied_data = $self->{attrs}{related_objects}; # nothing might have been inserted yet
2608 @cols_from_relations = keys %{ $implied_data || {} };
2611 my $eqs = $self->result_source->schema->storage->_extract_fixed_condition_columns($self->{cond}, 'consider_nulls');
2612 $implied_data = { map {
2613 ( ($eqs->{$_}||'') eq UNRESOLVABLE_CONDITION ) ? () : ( $_ => $eqs->{$_} )
2619 { %{ $self->_remove_alias($_, $alias) } }
2620 # precedence must be given to passed values over values inherited from
2621 # the cond, so the order here is important.
2622 ( $implied_data||(), $data)
2624 \@cols_from_relations
2628 # _has_resolved_attr
2630 # determines if the resultset defines at least one
2631 # of the attributes supplied
2633 # used to determine if a subquery is necessary
2635 # supports some virtual attributes:
2637 # This will scan for any joins being present on the resultset.
2638 # It is not a mere key-search but a deep inspection of {from}
2641 sub _has_resolved_attr {
2642 my ($self, @attr_names) = @_;
2644 my $attrs = $self->_resolved_attrs;
2648 for my $n (@attr_names) {
2649 if (grep { $n eq $_ } (qw/-join/) ) {
2650 $extra_checks{$n}++;
2654 my $attr = $attrs->{$n};
2656 next if not defined $attr;
2658 if (ref $attr eq 'HASH') {
2659 return 1 if keys %$attr;
2661 elsif (ref $attr eq 'ARRAY') {
2669 # a resolved join is expressed as a multi-level from
2671 $extra_checks{-join}
2673 ref $attrs->{from} eq 'ARRAY'
2675 @{$attrs->{from}} > 1
2683 # Remove the specified alias from the specified query hash. A copy is made so
2684 # the original query is not modified.
2687 my ($self, $query, $alias) = @_;
2689 my %orig = %{ $query || {} };
2692 foreach my $key (keys %orig) {
2694 $unaliased{$key} = $orig{$key};
2697 $unaliased{$1} = $orig{$key}
2698 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2708 =item Arguments: none
2710 =item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
2714 Returns the SQL query and bind vars associated with the invocant.
2716 This is generally used as the RHS for a subquery.
2723 my $attrs = { %{ $self->_resolved_attrs } };
2725 my $aq = $self->result_source->storage->_select_args_to_query (
2726 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
2736 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2738 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2742 my $artist = $schema->resultset('Artist')->find_or_new(
2743 { artist => 'fred' }, { key => 'artists' });
2745 $cd->cd_to_producer->find_or_new({ producer => $producer },
2746 { key => 'primary' });
2748 Find an existing record from this resultset using L</find>. if none exists,
2749 instantiate a new result object and return it. The object will not be saved
2750 into your storage until you call L<DBIx::Class::Row/insert> on it.
2752 You most likely want this method when looking for existing rows using a unique
2753 constraint that is not the primary key, or looking for related rows.
2755 If you want objects to be saved immediately, use L</find_or_create> instead.
2757 B<Note>: Make sure to read the documentation of L</find> and understand the
2758 significance of the C<key> attribute, as its lack may skew your search, and
2759 subsequently result in spurious new objects.
2761 B<Note>: Take care when using C<find_or_new> with a table having
2762 columns with default values that you intend to be automatically
2763 supplied by the database (e.g. an auto_increment primary key column).
2764 In normal usage, the value of such columns should NOT be included at
2765 all in the call to C<find_or_new>, even when set to C<undef>.
2771 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2772 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2773 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2776 return $self->new_result($hash);
2783 =item Arguments: \%col_data
2785 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2789 Attempt to create a single new row or a row with multiple related rows
2790 in the table represented by the resultset (and related tables). This
2791 will not check for duplicate rows before inserting, use
2792 L</find_or_create> to do that.
2794 To create one row for this resultset, pass a hashref of key/value
2795 pairs representing the columns of the table and the values you wish to
2796 store. If the appropriate relationships are set up, foreign key fields
2797 can also be passed an object representing the foreign row, and the
2798 value will be set to its primary key.
2800 To create related objects, pass a hashref of related-object column values
2801 B<keyed on the relationship name>. If the relationship is of type C<multi>
2802 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2803 The process will correctly identify columns holding foreign keys, and will
2804 transparently populate them from the keys of the corresponding relation.
2805 This can be applied recursively, and will work correctly for a structure
2806 with an arbitrary depth and width, as long as the relationships actually
2807 exists and the correct column data has been supplied.
2809 Instead of hashrefs of plain related data (key/value pairs), you may
2810 also pass new or inserted objects. New objects (not inserted yet, see
2811 L</new_result>), will be inserted into their appropriate tables.
2813 Effectively a shortcut for C<< ->new_result(\%col_data)->insert >>.
2815 Example of creating a new row.
2817 $person_rs->create({
2818 name=>"Some Person",
2819 email=>"somebody@someplace.com"
2822 Example of creating a new row and also creating rows in a related C<has_many>
2823 or C<has_one> resultset. Note Arrayref.
2826 { artistid => 4, name => 'Manufactured Crap', cds => [
2827 { title => 'My First CD', year => 2006 },
2828 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2833 Example of creating a new row and also creating a row in a related
2834 C<belongs_to> resultset. Note Hashref.
2837 title=>"Music for Silly Walks",
2840 name=>"Silly Musician",
2848 When subclassing ResultSet never attempt to override this method. Since
2849 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2850 lot of the internals simply never call it, so your override will be
2851 bypassed more often than not. Override either L<DBIx::Class::Row/new>
2852 or L<DBIx::Class::Row/insert> depending on how early in the
2853 L</create> process you need to intervene. See also warning pertaining to
2861 #my ($self, $col_data) = @_;
2862 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
2863 return shift->new_result(shift)->insert;
2866 =head2 find_or_create
2870 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2872 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2876 $cd->cd_to_producer->find_or_create({ producer => $producer },
2877 { key => 'primary' });
2879 Tries to find a record based on its primary key or unique constraints; if none
2880 is found, creates one and returns that instead.
2882 my $cd = $schema->resultset('CD')->find_or_create({
2884 artist => 'Massive Attack',
2885 title => 'Mezzanine',
2889 Also takes an optional C<key> attribute, to search by a specific key or unique
2890 constraint. For example:
2892 my $cd = $schema->resultset('CD')->find_or_create(
2894 artist => 'Massive Attack',
2895 title => 'Mezzanine',
2897 { key => 'cd_artist_title' }
2900 B<Note>: Make sure to read the documentation of L</find> and understand the
2901 significance of the C<key> attribute, as its lack may skew your search, and
2902 subsequently result in spurious row creation.
2904 B<Note>: Because find_or_create() reads from the database and then
2905 possibly inserts based on the result, this method is subject to a race
2906 condition. Another process could create a record in the table after
2907 the find has completed and before the create has started. To avoid
2908 this problem, use find_or_create() inside a transaction.
2910 B<Note>: Take care when using C<find_or_create> with a table having
2911 columns with default values that you intend to be automatically
2912 supplied by the database (e.g. an auto_increment primary key column).
2913 In normal usage, the value of such columns should NOT be included at
2914 all in the call to C<find_or_create>, even when set to C<undef>.
2916 See also L</find> and L</update_or_create>. For information on how to declare
2917 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2919 If you need to know if an existing row was found or a new one created use
2920 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2921 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2924 my $cd = $schema->resultset('CD')->find_or_new({
2926 artist => 'Massive Attack',
2927 title => 'Mezzanine',
2931 if( !$cd->in_storage ) {
2938 sub find_or_create {
2940 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2941 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2942 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2945 return $self->new_result($hash)->insert;
2948 =head2 update_or_create
2952 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2954 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2958 $resultset->update_or_create({ col => $val, ... });
2960 Like L</find_or_create>, but if a row is found it is immediately updated via
2961 C<< $found_row->update (\%col_data) >>.
2964 Takes an optional C<key> attribute to search on a specific unique constraint.
2967 # In your application
2968 my $cd = $schema->resultset('CD')->update_or_create(
2970 artist => 'Massive Attack',
2971 title => 'Mezzanine',
2974 { key => 'cd_artist_title' }
2977 $cd->cd_to_producer->update_or_create({
2978 producer => $producer,
2984 B<Note>: Make sure to read the documentation of L</find> and understand the
2985 significance of the C<key> attribute, as its lack may skew your search, and
2986 subsequently result in spurious row creation.
2988 B<Note>: Take care when using C<update_or_create> with a table having
2989 columns with default values that you intend to be automatically
2990 supplied by the database (e.g. an auto_increment primary key column).
2991 In normal usage, the value of such columns should NOT be included at
2992 all in the call to C<update_or_create>, even when set to C<undef>.
2994 See also L</find> and L</find_or_create>. For information on how to declare
2995 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2997 If you need to know if an existing row was updated or a new one created use
2998 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2999 to call L<DBIx::Class::Row/insert> to save the newly created row to the
3004 sub update_or_create {
3006 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
3007 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3009 my $row = $self->find($cond, $attrs);
3011 $row->update($cond);
3015 return $self->new_result($cond)->insert;
3018 =head2 update_or_new
3022 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
3024 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
3028 $resultset->update_or_new({ col => $val, ... });
3030 Like L</find_or_new> but if a row is found it is immediately updated via
3031 C<< $found_row->update (\%col_data) >>.
3035 # In your application
3036 my $cd = $schema->resultset('CD')->update_or_new(
3038 artist => 'Massive Attack',
3039 title => 'Mezzanine',
3042 { key => 'cd_artist_title' }
3045 if ($cd->in_storage) {
3046 # the cd was updated
3049 # the cd is not yet in the database, let's insert it
3053 B<Note>: Make sure to read the documentation of L</find> and understand the
3054 significance of the C<key> attribute, as its lack may skew your search, and
3055 subsequently result in spurious new objects.
3057 B<Note>: Take care when using C<update_or_new> with a table having
3058 columns with default values that you intend to be automatically
3059 supplied by the database (e.g. an auto_increment primary key column).
3060 In normal usage, the value of such columns should NOT be included at
3061 all in the call to C<update_or_new>, even when set to C<undef>.
3063 See also L</find>, L</find_or_create> and L</find_or_new>.
3069 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
3070 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3072 my $row = $self->find( $cond, $attrs );
3073 if ( defined $row ) {
3074 $row->update($cond);
3078 return $self->new_result($cond);
3085 =item Arguments: none
3087 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass> | undef
3091 Gets the contents of the cache for the resultset, if the cache is set.
3093 The cache is populated either by using the L</prefetch> attribute to
3094 L</search> or by calling L</set_cache>.
3106 =item Arguments: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3108 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3112 Sets the contents of the cache for the resultset. Expects an arrayref
3113 of objects of the same class as those produced by the resultset. Note that
3114 if the cache is set, the resultset will return the cached objects rather
3115 than re-querying the database even if the cache attr is not set.
3117 The contents of the cache can also be populated by using the
3118 L</prefetch> attribute to L</search>.
3123 my ( $self, $data ) = @_;
3124 $self->throw_exception("set_cache requires an arrayref")
3125 if defined($data) && (ref $data ne 'ARRAY');
3126 $self->{all_cache} = $data;
3133 =item Arguments: none
3135 =item Return Value: undef
3139 Clears the cache for the resultset.
3144 shift->set_cache(undef);
3151 =item Arguments: none
3153 =item Return Value: true, if the resultset has been paginated
3161 return !!$self->{attrs}{page};
3168 =item Arguments: none
3170 =item Return Value: true, if the resultset has been ordered with C<order_by>.
3178 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
3181 =head2 related_resultset
3185 =item Arguments: $rel_name
3187 =item Return Value: L<$resultset|/search>
3191 Returns a related resultset for the supplied relationship name.
3193 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
3197 sub related_resultset {
3198 $_[0]->throw_exception(
3199 'Extra arguments to $rs->related_resultset() were always quietly '
3200 . 'discarded without consideration, you need to switch to '
3201 . '...->related_resultset( $relname )->search_rs( $search, $args ) instead.'
3204 return $_[0]->{related_resultsets}{$_[1]}
3205 if defined $_[0]->{related_resultsets}{$_[1]};
3207 my ($self, $rel) = @_;
3209 return $self->{related_resultsets}{$rel} = do {
3210 my $rsrc = $self->result_source;
3211 my $rel_info = $rsrc->relationship_info($rel);
3213 $self->throw_exception(
3214 "search_related: result source '" . $rsrc->source_name .
3215 "' has no such relationship $rel")
3218 my $attrs = $self->_chain_relationship($rel);
3220 my $storage = $rsrc->schema->storage;
3222 # Previously this atribute was deleted (instead of being set as it is now)
3223 # Doing so seems to be harmless in all available test permutations
3224 # See also 01d59a6a6 and mst's comment below
3226 $attrs->{alias} = $storage->relname_to_table_alias(
3228 $attrs->{seen_join}{$rel}
3231 # since this is search_related, and we already slid the select window inwards
3232 # (the select/as attrs were deleted in the beginning), we need to flip all
3233 # left joins to inner, so we get the expected results
3234 # read the comment on top of the actual function to see what this does
3235 $attrs->{from} = $storage->_inner_join_to_node( $attrs->{from}, $attrs->{alias} );
3237 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3238 delete $attrs->{result_class};
3242 # The reason we do this now instead of passing the alias to the
3243 # search_rs below is that if you wrap/overload resultset on the
3244 # source you need to know what alias it's -going- to have for things
3245 # to work sanely (e.g. RestrictWithObject wants to be able to add
3246 # extra query restrictions, and these may need to be $alias.)
3247 # -- mst ~ 2007 (01d59a6a6)
3249 # FIXME - this seems to be no longer neccessary (perhaps due to the
3250 # advances in relcond resolution. Testing DBIC::S::RWO and its only
3251 # dependent (as of Jun 2015 ) does not yield any difference with or
3252 # without this line. Nevertheless keep it as is for now, to minimize
3253 # churn, there is enough potential for breakage in 0.0829xx as it is
3254 # -- ribasushi Jun 2015
3256 my $rel_source = $rsrc->related_source($rel);
3257 local $rel_source->resultset_attributes->{alias} = $attrs->{alias};
3259 $rel_source->resultset->search_rs( undef, $attrs );
3262 if (my $cache = $self->get_cache) {
3263 my @related_cache = map
3264 { $_->related_resultset($rel)->get_cache || () }
3268 $new->set_cache([ map @$_, @related_cache ]) if @related_cache == @$cache;
3275 =head2 current_source_alias
3279 =item Arguments: none
3281 =item Return Value: $source_alias
3285 Returns the current table alias for the result source this resultset is built
3286 on, that will be used in the SQL query. Usually it is C<me>.
3288 Currently the source alias that refers to the result set returned by a
3289 L</search>/L</find> family method depends on how you got to the resultset: it's
3290 C<me> by default, but eg. L</search_related> aliases it to the related result
3291 source name (and keeps C<me> referring to the original result set). The long
3292 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3293 (and make this method unnecessary).
3295 Thus it's currently necessary to use this method in predefined queries (see
3296 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3297 source alias of the current result set:
3299 # in a result set class
3301 my ($self, $user) = @_;
3303 my $me = $self->current_source_alias;
3305 return $self->search({
3306 "$me.modified" => $user->id,
3310 The alias of L<newly created resultsets|/search> can be altered by the
3311 L<alias attribute|/alias>.
3315 sub current_source_alias {
3316 return (shift->{attrs} || {})->{alias} || 'me';
3319 =head2 as_subselect_rs
3323 =item Arguments: none
3325 =item Return Value: L<$resultset|/search>
3329 Act as a barrier to SQL symbols. The resultset provided will be made into a
3330 "virtual view" by including it as a subquery within the from clause. From this
3331 point on, any joined tables are inaccessible to ->search on the resultset (as if
3332 it were simply where-filtered without joins). For example:
3334 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3336 # 'x' now pollutes the query namespace
3338 # So the following works as expected
3339 my $ok_rs = $rs->search({'x.other' => 1});
3341 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3342 # def) we look for one row with contradictory terms and join in another table
3343 # (aliased 'x_2') which we never use
3344 my $broken_rs = $rs->search({'x.name' => 'def'});
3346 my $rs2 = $rs->as_subselect_rs;
3348 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3349 my $not_joined_rs = $rs2->search({'x.other' => 1});
3351 # works as expected: finds a 'table' row related to two x rows (abc and def)
3352 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3354 Another example of when one might use this would be to select a subset of
3355 columns in a group by clause:
3357 my $rs = $schema->resultset('Bar')->search(undef, {
3358 group_by => [qw{ id foo_id baz_id }],
3359 })->as_subselect_rs->search(undef, {
3360 columns => [qw{ id foo_id }]
3363 In the above example normally columns would have to be equal to the group by,
3364 but because we isolated the group by into a subselect the above works.
3368 sub as_subselect_rs {
3371 my $attrs = $self->_resolved_attrs;
3373 my $fresh_rs = (ref $self)->new (
3374 $self->result_source
3377 # these pieces will be locked in the subquery
3378 delete $fresh_rs->{cond};
3379 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3381 return $fresh_rs->search( {}, {
3383 $attrs->{alias} => $self->as_query,
3384 -alias => $attrs->{alias},
3385 -rsrc => $self->result_source,
3387 alias => $attrs->{alias},
3391 # This code is called by search_related, and makes sure there
3392 # is clear separation between the joins before, during, and
3393 # after the relationship. This information is needed later
3394 # in order to properly resolve prefetch aliases (any alias
3395 # with a relation_chain_depth less than the depth of the
3396 # current prefetch is not considered)
3398 # The increments happen twice per join. An even number means a
3399 # relationship specified via a search_related, whereas an odd
3400 # number indicates a join/prefetch added via attributes
3402 # Also this code will wrap the current resultset (the one we
3403 # chain to) in a subselect IFF it contains limiting attributes
3404 sub _chain_relationship {
3405 my ($self, $rel) = @_;
3406 my $source = $self->result_source;
3407 my $attrs = { %{$self->{attrs}||{}} };
3409 # we need to take the prefetch the attrs into account before we
3410 # ->_resolve_join as otherwise they get lost - captainL
3411 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3413 delete @{$attrs}{qw/join prefetch collapse group_by distinct _grouped_by_distinct select as columns +select +as +columns/};
3415 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3418 my @force_subq_attrs = qw/offset rows group_by having/;
3421 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3423 $self->_has_resolved_attr (@force_subq_attrs)
3425 # Nuke the prefetch (if any) before the new $rs attrs
3426 # are resolved (prefetch is useless - we are wrapping
3427 # a subquery anyway).
3428 my $rs_copy = $self->search;
3429 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3430 $rs_copy->{attrs}{join},
3431 delete $rs_copy->{attrs}{prefetch},
3436 -alias => $attrs->{alias},
3437 $attrs->{alias} => $rs_copy->as_query,
3439 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3440 $seen->{-relation_chain_depth} = 0;
3442 elsif ($attrs->{from}) { #shallow copy suffices
3443 $from = [ @{$attrs->{from}} ];
3448 -alias => $attrs->{alias},
3449 $attrs->{alias} => $source->from,
3453 my $jpath = ($seen->{-relation_chain_depth})
3454 ? $from->[-1][0]{-join_path}
3457 my @requested_joins = $source->_resolve_join(
3464 push @$from, @requested_joins;
3466 $seen->{-relation_chain_depth}++;
3468 # if $self already had a join/prefetch specified on it, the requested
3469 # $rel might very well be already included. What we do in this case
3470 # is effectively a no-op (except that we bump up the chain_depth on
3471 # the join in question so we could tell it *is* the search_related)
3474 # we consider the last one thus reverse
3475 for my $j (reverse @requested_joins) {
3476 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3477 if ($rel eq $last_j) {
3478 $j->[0]{-relation_chain_depth}++;
3484 unless ($already_joined) {
3485 push @$from, $source->_resolve_join(
3493 $seen->{-relation_chain_depth}++;
3495 return {%$attrs, from => $from, seen_join => $seen};
3498 sub _resolved_attrs {
3500 return $self->{_attrs} if $self->{_attrs};
3502 my $attrs = { %{ $self->{attrs} || {} } };
3503 my $source = $attrs->{result_source} = $self->result_source;
3504 my $alias = $attrs->{alias};
3506 $self->throw_exception("Specifying distinct => 1 in conjunction with collapse => 1 is unsupported")
3507 if $attrs->{collapse} and $attrs->{distinct};
3510 # Sanity check the paging attributes
3511 # SQLMaker does it too, but in case of a software_limit we'll never get there
3512 if (defined $attrs->{offset}) {
3513 $self->throw_exception('A supplied offset attribute must be a non-negative integer')
3514 if ( $attrs->{offset} =~ /[^0-9]/ or $attrs->{offset} < 0 );
3516 if (defined $attrs->{rows}) {
3517 $self->throw_exception("The rows attribute must be a positive integer if present")
3518 if ( $attrs->{rows} =~ /[^0-9]/ or $attrs->{rows} <= 0 );
3522 # default selection list
3523 $attrs->{columns} = [ $source->columns ]
3524 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3526 # merge selectors together
3527 for (qw/columns select as/) {
3528 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3529 if $attrs->{$_} or $attrs->{"+$_"};
3532 # disassemble columns
3534 if (my $cols = delete $attrs->{columns}) {
3535 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3536 if (ref $c eq 'HASH') {
3537 for my $as (sort keys %$c) {
3538 push @sel, $c->{$as};
3549 # when trying to weed off duplicates later do not go past this point -
3550 # everything added from here on is unbalanced "anyone's guess" stuff
3551 my $dedup_stop_idx = $#as;
3553 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3555 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3556 if $attrs->{select};
3558 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3559 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3561 # disqualify all $alias.col as-bits (inflate-map mandated)
3562 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3564 # de-duplicate the result (remove *identical* select/as pairs)
3565 # and also die on duplicate {as} pointing to different {select}s
3566 # not using a c-style for as the condition is prone to shrinkage
3569 while ($i <= $dedup_stop_idx) {
3570 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3575 elsif ($seen->{$as[$i]}++) {
3576 $self->throw_exception(
3577 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3585 $attrs->{select} = \@sel;
3586 $attrs->{as} = \@as;
3588 $attrs->{from} ||= [{
3590 -alias => $self->{attrs}{alias},
3591 $self->{attrs}{alias} => $source->from,
3594 if ( $attrs->{join} || $attrs->{prefetch} ) {
3596 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3597 if ref $attrs->{from} ne 'ARRAY';
3599 my $join = (delete $attrs->{join}) || {};
3601 if ( defined $attrs->{prefetch} ) {
3602 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3605 $attrs->{from} = # have to copy here to avoid corrupting the original
3607 @{ $attrs->{from} },
3608 $source->_resolve_join(
3611 { %{ $attrs->{seen_join} || {} } },
3612 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3613 ? $attrs->{from}[-1][0]{-join_path}
3621 for my $attr (qw(order_by group_by)) {
3623 if ( defined $attrs->{$attr} ) {
3625 ref( $attrs->{$attr} ) eq 'ARRAY'
3626 ? [ @{ $attrs->{$attr} } ]
3627 : [ $attrs->{$attr} || () ]
3630 delete $attrs->{$attr} unless @{$attrs->{$attr}};
3635 # set collapse default based on presence of prefetch
3638 defined $attrs->{prefetch}
3640 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3642 $self->throw_exception("Specifying prefetch in conjunction with an explicit collapse => 0 is unsupported")
3643 if defined $attrs->{collapse} and ! $attrs->{collapse};
3645 $attrs->{collapse} = 1;
3649 # run through the resulting joinstructure (starting from our current slot)
3650 # and unset collapse if proven unnecessary
3652 # also while we are at it find out if the current root source has
3653 # been premultiplied by previous related_source chaining
3655 # this allows to predict whether a root object with all other relation
3656 # data set to NULL is in fact unique
3657 if ($attrs->{collapse}) {
3659 if (ref $attrs->{from} eq 'ARRAY') {
3661 if (@{$attrs->{from}} == 1) {
3662 # no joins - no collapse
3663 $attrs->{collapse} = 0;
3666 # find where our table-spec starts
3667 my @fromlist = @{$attrs->{from}};
3669 my $t = shift @fromlist;
3672 # me vs join from-spec distinction - a ref means non-root
3673 if (ref $t eq 'ARRAY') {
3675 $is_multi ||= ! $t->{-is_single};
3677 last if ($t->{-alias} && $t->{-alias} eq $alias);
3678 $attrs->{_main_source_premultiplied} ||= $is_multi;
3681 # no non-singles remaining, nor any premultiplication - nothing to collapse
3683 ! $attrs->{_main_source_premultiplied}
3685 ! List::Util::first { ! $_->[0]{-is_single} } @fromlist
3687 $attrs->{collapse} = 0;
3693 # if we can not analyze the from - err on the side of safety
3694 $attrs->{_main_source_premultiplied} = 1;
3699 # generate the distinct induced group_by before injecting the prefetched select/as parts
3700 if (delete $attrs->{distinct}) {
3701 if ($attrs->{group_by}) {
3702 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3705 $attrs->{_grouped_by_distinct} = 1;
3706 # distinct affects only the main selection part, not what prefetch may add below
3707 ($attrs->{group_by}, my $new_order) = $source->storage->_group_over_selection($attrs);
3709 # FIXME possibly ignore a rewritten order_by (may turn out to be an issue)
3710 # The thinking is: if we are collapsing the subquerying prefetch engine will
3711 # rip stuff apart for us anyway, and we do not want to have a potentially
3712 # function-converted external order_by
3713 # ( there is an explicit if ( collapse && _grouped_by_distinct ) check in DBIHacks )
3714 $attrs->{order_by} = $new_order unless $attrs->{collapse};
3719 # generate selections based on the prefetch helper
3722 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3723 if $attrs->{_dark_selector};
3725 # this is a separate structure (we don't look in {from} directly)
3726 # as the resolver needs to shift things off the lists to work
3727 # properly (identical-prefetches on different branches)
3728 my $joined_node_aliases_map = {};
3729 if (ref $attrs->{from} eq 'ARRAY') {
3731 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3733 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3734 next unless $j->[0]{-alias};
3735 next unless $j->[0]{-join_path};
3736 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3738 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3740 my $p = $joined_node_aliases_map;
3741 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3742 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3746 ( push @{$attrs->{select}}, $_->[0] ) and ( push @{$attrs->{as}}, $_->[1] )
3747 for $source->_resolve_selection_from_prefetch( $prefetch, $joined_node_aliases_map );
3751 $attrs->{_simple_passthrough_construction} = !(
3754 grep { $_ =~ /\./ } @{$attrs->{as}}
3758 # if both page and offset are specified, produce a combined offset
3759 # even though it doesn't make much sense, this is what pre 081xx has
3761 if (my $page = delete $attrs->{page}) {
3763 ($attrs->{rows} * ($page - 1))
3765 ($attrs->{offset} || 0)
3769 return $self->{_attrs} = $attrs;
3773 my ($self, $attr) = @_;
3775 if (ref $attr eq 'HASH') {
3776 return $self->_rollout_hash($attr);
3777 } elsif (ref $attr eq 'ARRAY') {
3778 return $self->_rollout_array($attr);
3784 sub _rollout_array {
3785 my ($self, $attr) = @_;
3788 foreach my $element (@{$attr}) {
3789 if (ref $element eq 'HASH') {
3790 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3791 } elsif (ref $element eq 'ARRAY') {
3792 # XXX - should probably recurse here
3793 push( @rolled_array, @{$self->_rollout_array($element)} );
3795 push( @rolled_array, $element );
3798 return \@rolled_array;
3802 my ($self, $attr) = @_;
3805 foreach my $key (keys %{$attr}) {
3806 push( @rolled_array, { $key => $attr->{$key} } );
3808 return \@rolled_array;
3811 sub _calculate_score {
3812 my ($self, $a, $b) = @_;
3814 if (defined $a xor defined $b) {
3817 elsif (not defined $a) {
3821 if (ref $b eq 'HASH') {
3822 my ($b_key) = keys %{$b};
3823 $b_key = '' if ! defined $b_key;
3824 if (ref $a eq 'HASH') {
3825 my ($a_key) = keys %{$a};
3826 $a_key = '' if ! defined $a_key;
3827 if ($a_key eq $b_key) {
3828 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3833 return ($a eq $b_key) ? 1 : 0;
3836 if (ref $a eq 'HASH') {
3837 my ($a_key) = keys %{$a};
3838 return ($b eq $a_key) ? 1 : 0;
3840 return ($b eq $a) ? 1 : 0;
3845 sub _merge_joinpref_attr {
3846 my ($self, $orig, $import) = @_;
3848 return $import unless defined($orig);
3849 return $orig unless defined($import);
3851 $orig = $self->_rollout_attr($orig);
3852 $import = $self->_rollout_attr($import);
3855 foreach my $import_element ( @{$import} ) {
3856 # find best candidate from $orig to merge $b_element into
3857 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3858 foreach my $orig_element ( @{$orig} ) {
3859 my $score = $self->_calculate_score( $orig_element, $import_element );
3860 if ($score > $best_candidate->{score}) {
3861 $best_candidate->{position} = $position;
3862 $best_candidate->{score} = $score;
3866 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3867 $import_key = '' if not defined $import_key;
3869 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3870 push( @{$orig}, $import_element );
3872 my $orig_best = $orig->[$best_candidate->{position}];
3873 # merge orig_best and b_element together and replace original with merged
3874 if (ref $orig_best ne 'HASH') {
3875 $orig->[$best_candidate->{position}] = $import_element;
3876 } elsif (ref $import_element eq 'HASH') {
3877 my ($key) = keys %{$orig_best};
3878 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3881 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3884 return @$orig ? $orig : ();
3892 require Hash::Merge;
3893 my $hm = Hash::Merge->new;
3895 $hm->specify_behavior({
3898 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3900 if ($defl xor $defr) {
3901 return [ $defl ? $_[0] : $_[1] ];
3906 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3910 return [$_[0], $_[1]];
3914 return $_[1] if !defined $_[0];
3915 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3916 return [$_[0], @{$_[1]}]
3919 return [] if !defined $_[0] and !keys %{$_[1]};
3920 return [ $_[1] ] if !defined $_[0];
3921 return [ $_[0] ] if !keys %{$_[1]};
3922 return [$_[0], $_[1]]
3927 return $_[0] if !defined $_[1];
3928 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3929 return [@{$_[0]}, $_[1]]
3932 my @ret = @{$_[0]} or return $_[1];
3933 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3934 my %idx = map { $_ => 1 } @ret;
3935 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3939 return [ $_[1] ] if ! @{$_[0]};
3940 return $_[0] if !keys %{$_[1]};
3941 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3942 return [ @{$_[0]}, $_[1] ];
3947 return [] if !keys %{$_[0]} and !defined $_[1];
3948 return [ $_[0] ] if !defined $_[1];
3949 return [ $_[1] ] if !keys %{$_[0]};
3950 return [$_[0], $_[1]]
3953 return [] if !keys %{$_[0]} and !@{$_[1]};
3954 return [ $_[0] ] if !@{$_[1]};
3955 return $_[1] if !keys %{$_[0]};
3956 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3957 return [ $_[0], @{$_[1]} ];
3960 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3961 return [ $_[0] ] if !keys %{$_[1]};
3962 return [ $_[1] ] if !keys %{$_[0]};
3963 return [ $_[0] ] if $_[0] eq $_[1];
3964 return [ $_[0], $_[1] ];
3967 } => 'DBIC_RS_ATTR_MERGER');
3971 return $hm->merge ($_[1], $_[2]);
3975 sub STORABLE_freeze {
3976 my ($self, $cloning) = @_;
3977 my $to_serialize = { %$self };
3979 # A cursor in progress can't be serialized (and would make little sense anyway)
3980 # the parser can be regenerated (and can't be serialized)
3981 delete @{$to_serialize}{qw/cursor _row_parser _result_inflator/};
3983 # nor is it sensical to store a not-yet-fired-count pager
3984 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3985 delete $to_serialize->{pager};
3988 Storable::nfreeze($to_serialize);
3991 # need this hook for symmetry
3993 my ($self, $cloning, $serialized) = @_;
3995 %$self = %{ Storable::thaw($serialized) };
4001 =head2 throw_exception
4003 See L<DBIx::Class::Schema/throw_exception> for details.
4007 sub throw_exception {
4010 if (ref $self and my $rsrc = $self->result_source) {
4011 $rsrc->throw_exception(@_)
4014 DBIx::Class::Exception->throw(@_);
4022 # XXX: FIXME: Attributes docs need clearing up
4026 Attributes are used to refine a ResultSet in various ways when
4027 searching for data. They can be passed to any method which takes an
4028 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
4031 Default attributes can be set on the result class using
4032 L<DBIx::Class::ResultSource/resultset_attributes>. (Please read
4033 the CAVEATS on that feature before using it!)
4035 These are in no particular order:
4041 =item Value: ( $order_by | \@order_by | \%order_by )
4045 Which column(s) to order the results by.
4047 [The full list of suitable values is documented in
4048 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
4051 If a single column name, or an arrayref of names is supplied, the
4052 argument is passed through directly to SQL. The hashref syntax allows
4053 for connection-agnostic specification of ordering direction:
4055 For descending order:
4057 order_by => { -desc => [qw/col1 col2 col3/] }
4059 For explicit ascending order:
4061 order_by => { -asc => 'col' }
4063 The old scalarref syntax (i.e. order_by => \'year DESC') is still
4064 supported, although you are strongly encouraged to use the hashref
4065 syntax as outlined above.
4071 =item Value: \@columns | \%columns | $column
4075 Shortcut to request a particular set of columns to be retrieved. Each
4076 column spec may be a string (a table column name), or a hash (in which
4077 case the key is the C<as> value, and the value is used as the C<select>
4078 expression). Adds the L</current_source_alias> onto the start of any column without a C<.> in
4079 it and sets C<select> from that, then auto-populates C<as> from
4080 C<select> as normal. (You may also use the C<cols> attribute, as in
4081 earlier versions of DBIC, but this is deprecated)
4083 Essentially C<columns> does the same as L</select> and L</as>.
4085 columns => [ 'some_column', { dbic_slot => 'another_column' } ]
4089 select => [qw(some_column another_column)],
4090 as => [qw(some_column dbic_slot)]
4092 If you want to individually retrieve related columns (in essence perform
4093 manual L</prefetch>) you have to make sure to specify the correct inflation slot
4094 chain such that it matches existing relationships:
4096 my $rs = $schema->resultset('Artist')->search({}, {
4097 # required to tell DBIC to collapse has_many relationships
4099 join => { cds => 'tracks' },
4101 'cds.cdid' => 'cds.cdid',
4102 'cds.tracks.title' => 'tracks.title',
4106 Like elsewhere, literal SQL or literal values can be included by using a
4107 scalar reference or a literal bind value, and these values will be available
4108 in the result with C<get_column> (see also
4109 L<SQL::Abstract/Literal SQL and value type operators>):
4111 # equivalent SQL: SELECT 1, 'a string', IF(my_column,?,?) ...
4112 # bind values: $true_value, $false_value
4116 bar => \q{'a string'},
4117 baz => \[ 'IF(my_column,?,?)', $true_value, $false_value ],
4123 B<NOTE:> You B<MUST> explicitly quote C<'+columns'> when using this attribute.
4124 Not doing so causes Perl to incorrectly interpret C<+columns> as a bareword
4125 with a unary plus operator before it, which is the same as simply C<columns>.
4129 =item Value: \@extra_columns
4133 Indicates additional columns to be selected from storage. Works the same as
4134 L</columns> but adds columns to the current selection. (You may also use the
4135 C<include_columns> attribute, as in earlier versions of DBIC, but this is
4138 $schema->resultset('CD')->search(undef, {
4139 '+columns' => ['artist.name'],
4143 would return all CDs and include a 'name' column to the information
4144 passed to object inflation. Note that the 'artist' is the name of the
4145 column (or relationship) accessor, and 'name' is the name of the column
4146 accessor in the related table.
4152 =item Value: \@select_columns
4156 Indicates which columns should be selected from the storage. You can use
4157 column names, or in the case of RDBMS back ends, function or stored procedure
4160 $rs = $schema->resultset('Employee')->search(undef, {
4163 { count => 'employeeid' },
4164 { max => { length => 'name' }, -as => 'longest_name' }
4169 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
4171 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
4172 use L</select>, to instruct DBIx::Class how to store the result of the column.
4174 Also note that the L</as> attribute has B<nothing to do> with the SQL-side
4175 C<AS> identifier aliasing. You B<can> alias a function (so you can use it e.g.
4176 in an C<ORDER BY> clause), however this is done via the C<-as> B<select
4177 function attribute> supplied as shown in the example above.
4181 B<NOTE:> You B<MUST> explicitly quote C<'+select'> when using this attribute.
4182 Not doing so causes Perl to incorrectly interpret C<+select> as a bareword
4183 with a unary plus operator before it, which is the same as simply C<select>.
4187 =item Value: \@extra_select_columns
4191 Indicates additional columns to be selected from storage. Works the same as
4192 L</select> but adds columns to the current selection, instead of specifying
4193 a new explicit list.
4199 =item Value: \@inflation_names
4203 Indicates DBIC-side names for object inflation. That is L</as> indicates the
4204 slot name in which the column value will be stored within the
4205 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
4206 identifier by the C<get_column> method (or via the object accessor B<if one
4207 with the same name already exists>) as shown below.
4209 The L</as> attribute has B<nothing to do> with the SQL-side identifier
4210 aliasing C<AS>. See L</select> for details.
4212 $rs = $schema->resultset('Employee')->search(undef, {
4215 { count => 'employeeid' },
4216 { max => { length => 'name' }, -as => 'longest_name' }
4225 If the object against which the search is performed already has an accessor
4226 matching a column name specified in C<as>, the value can be retrieved using
4227 the accessor as normal:
4229 my $name = $employee->name();
4231 If on the other hand an accessor does not exist in the object, you need to
4232 use C<get_column> instead:
4234 my $employee_count = $employee->get_column('employee_count');
4236 You can create your own accessors if required - see
4237 L<DBIx::Class::Manual::Cookbook> for details.
4241 B<NOTE:> You B<MUST> explicitly quote C<'+as'> when using this attribute.
4242 Not doing so causes Perl to incorrectly interpret C<+as> as a bareword
4243 with a unary plus operator before it, which is the same as simply C<as>.
4247 =item Value: \@extra_inflation_names
4251 Indicates additional inflation names for selectors added via L</+select>. See L</as>.
4257 =item Value: ($rel_name | \@rel_names | \%rel_names)
4261 Contains a list of relationships that should be joined for this query. For
4264 # Get CDs by Nine Inch Nails
4265 my $rs = $schema->resultset('CD')->search(
4266 { 'artist.name' => 'Nine Inch Nails' },
4267 { join => 'artist' }
4270 Can also contain a hash reference to refer to the other relation's relations.
4273 package MyApp::Schema::Track;
4274 use base qw/DBIx::Class/;
4275 __PACKAGE__->table('track');
4276 __PACKAGE__->add_columns(qw/trackid cd position title/);
4277 __PACKAGE__->set_primary_key('trackid');
4278 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
4281 # In your application
4282 my $rs = $schema->resultset('Artist')->search(
4283 { 'track.title' => 'Teardrop' },
4285 join => { cd => 'track' },
4286 order_by => 'artist.name',
4290 You need to use the relationship (not the table) name in conditions,
4291 because they are aliased as such. The current table is aliased as "me", so
4292 you need to use me.column_name in order to avoid ambiguity. For example:
4294 # Get CDs from 1984 with a 'Foo' track
4295 my $rs = $schema->resultset('CD')->search(
4298 'tracks.name' => 'Foo'
4300 { join => 'tracks' }
4303 If the same join is supplied twice, it will be aliased to <rel>_2 (and
4304 similarly for a third time). For e.g.
4306 my $rs = $schema->resultset('Artist')->search({
4307 'cds.title' => 'Down to Earth',
4308 'cds_2.title' => 'Popular',
4310 join => [ qw/cds cds/ ],
4313 will return a set of all artists that have both a cd with title 'Down
4314 to Earth' and a cd with title 'Popular'.
4316 If you want to fetch related objects from other tables as well, see L</prefetch>
4319 NOTE: An internal join-chain pruner will discard certain joins while
4320 constructing the actual SQL query, as long as the joins in question do not
4321 affect the retrieved result. This for example includes 1:1 left joins
4322 that are not part of the restriction specification (WHERE/HAVING) nor are
4323 a part of the query selection.
4325 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4331 =item Value: (0 | 1)
4335 When set to a true value, indicates that any rows fetched from joined has_many
4336 relationships are to be aggregated into the corresponding "parent" object. For
4337 example, the resultset:
4339 my $rs = $schema->resultset('CD')->search({}, {
4340 '+columns' => [ qw/ tracks.title tracks.position / ],
4345 While executing the following query:
4347 SELECT me.*, tracks.title, tracks.position
4349 LEFT JOIN track tracks
4350 ON tracks.cdid = me.cdid
4352 Will return only as many objects as there are rows in the CD source, even
4353 though the result of the query may span many rows. Each of these CD objects
4354 will in turn have multiple "Track" objects hidden behind the has_many
4355 generated accessor C<tracks>. Without C<< collapse => 1 >>, the return values
4356 of this resultset would be as many CD objects as there are tracks (a "Cartesian
4357 product"), with each CD object containing exactly one of all fetched Track data.
4359 When a collapse is requested on a non-ordered resultset, an order by some
4360 unique part of the main source (the left-most table) is inserted automatically.
4361 This is done so that the resultset is allowed to be "lazy" - calling
4362 L<< $rs->next|/next >> will fetch only as many rows as it needs to build the next
4363 object with all of its related data.
4365 If an L</order_by> is already declared, and orders the resultset in a way that
4366 makes collapsing as described above impossible (e.g. C<< ORDER BY
4367 has_many_rel.column >> or C<ORDER BY RANDOM()>), DBIC will automatically
4368 switch to "eager" mode and slurp the entire resultset before constructing the
4369 first object returned by L</next>.
4371 Setting this attribute on a resultset that does not join any has_many
4372 relations is a no-op.
4374 For a more in-depth discussion, see L</PREFETCHING>.
4380 =item Value: ($rel_name | \@rel_names | \%rel_names)
4384 This attribute is a shorthand for specifying a L</join> spec, adding all
4385 columns from the joined related sources as L</+columns> and setting
4386 L</collapse> to a true value. It can be thought of as a rough B<superset>
4387 of the L</join> attribute.
4389 For example, the following two queries are equivalent:
4391 my $rs = $schema->resultset('Artist')->search({}, {
4392 prefetch => { cds => ['genre', 'tracks' ] },
4397 my $rs = $schema->resultset('Artist')->search({}, {
4398 join => { cds => ['genre', 'tracks' ] },
4402 { +{ "cds.$_" => "cds.$_" } }
4403 $schema->source('Artist')->related_source('cds')->columns
4406 { +{ "cds.genre.$_" => "genre.$_" } }
4407 $schema->source('Artist')->related_source('cds')->related_source('genre')->columns
4410 { +{ "cds.tracks.$_" => "tracks.$_" } }
4411 $schema->source('Artist')->related_source('cds')->related_source('tracks')->columns
4416 Both producing the following SQL:
4418 SELECT me.artistid, me.name, me.rank, me.charfield,
4419 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track,
4420 genre.genreid, genre.name,
4421 tracks.trackid, tracks.cd, tracks.position, tracks.title, tracks.last_updated_on, tracks.last_updated_at
4424 ON cds.artist = me.artistid
4425 LEFT JOIN genre genre
4426 ON genre.genreid = cds.genreid
4427 LEFT JOIN track tracks
4428 ON tracks.cd = cds.cdid
4429 ORDER BY me.artistid
4431 While L</prefetch> implies a L</join>, it is ok to mix the two together, as
4432 the arguments are properly merged and generally do the right thing. For
4433 example, you may want to do the following:
4435 my $artists_and_cds_without_genre = $schema->resultset('Artist')->search(
4436 { 'genre.genreid' => undef },
4438 join => { cds => 'genre' },
4443 Which generates the following SQL:
4445 SELECT me.artistid, me.name, me.rank, me.charfield,
4446 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track
4449 ON cds.artist = me.artistid
4450 LEFT JOIN genre genre
4451 ON genre.genreid = cds.genreid
4452 WHERE genre.genreid IS NULL
4453 ORDER BY me.artistid
4455 For a more in-depth discussion, see L</PREFETCHING>.
4461 =item Value: $source_alias
4465 Sets the source alias for the query. Normally, this defaults to C<me>, but
4466 nested search queries (sub-SELECTs) might need specific aliases set to
4467 reference inner queries. For example:
4470 ->related_resultset('CDs')
4471 ->related_resultset('Tracks')
4473 'track.id' => { -ident => 'none_search.id' },
4477 my $ids = $self->search({
4480 alias => 'none_search',
4481 group_by => 'none_search.id',
4482 })->get_column('id')->as_query;
4484 $self->search({ id => { -in => $ids } })
4486 This attribute is directly tied to L</current_source_alias>.
4496 Makes the resultset paged and specifies the page to retrieve. Effectively
4497 identical to creating a non-pages resultset and then calling ->page($page)
4500 If L</rows> attribute is not specified it defaults to 10 rows per page.
4502 When you have a paged resultset, L</count> will only return the number
4503 of rows in the page. To get the total, use the L</pager> and call
4504 C<total_entries> on it.
4514 Specifies the maximum number of rows for direct retrieval or the number of
4515 rows per page if the page attribute or method is used.
4521 =item Value: $offset
4525 Specifies the (zero-based) row number for the first row to be returned, or the
4526 of the first row of the first page if paging is used.
4528 =head2 software_limit
4532 =item Value: (0 | 1)
4536 When combined with L</rows> and/or L</offset> the generated SQL will not
4537 include any limit dialect stanzas. Instead the entire result will be selected
4538 as if no limits were specified, and DBIC will perform the limit locally, by
4539 artificially advancing and finishing the resulting L</cursor>.
4541 This is the recommended way of performing resultset limiting when no sane RDBMS
4542 implementation is available (e.g.
4543 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4544 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4550 =item Value: \@columns
4554 A arrayref of columns to group by. Can include columns of joined tables.
4556 group_by => [qw/ column1 column2 ... /]
4562 =item Value: $condition
4566 The HAVING operator specifies a B<secondary> condition applied to the set
4567 after the grouping calculations have been done. In other words it is a
4568 constraint just like L</where> (and accepting the same
4569 L<SQL::Abstract syntax|SQL::Abstract/WHERE CLAUSES>) applied to the data
4570 as it exists after GROUP BY has taken place. Specifying L</having> without
4571 L</group_by> is a logical mistake, and a fatal error on most RDBMS engines.
4575 having => { 'count_employee' => { '>=', 100 } }
4577 or with an in-place function in which case literal SQL is required:
4579 having => \[ 'count(employee) >= ?', 100 ]
4585 =item Value: (0 | 1)
4589 Set to 1 to automatically generate a L</group_by> clause based on the selection
4590 (including intelligent handling of L</order_by> contents). Note that the group
4591 criteria calculation takes place over the B<final> selection. This includes
4592 any L</+columns>, L</+select> or L</order_by> additions in subsequent
4593 L</search> calls, and standalone columns selected via
4594 L<DBIx::Class::ResultSetColumn> (L</get_column>). A notable exception are the
4595 extra selections specified via L</prefetch> - such selections are explicitly
4596 excluded from group criteria calculations.
4598 If the final ResultSet also explicitly defines a L</group_by> attribute, this
4599 setting is ignored and an appropriate warning is issued.
4603 Adds extra conditions to the resultset, combined with the preexisting C<WHERE>
4604 conditions, same as the B<first> argument to the L<search operator|/search>
4606 # only return rows WHERE deleted IS NULL for all searches
4607 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4609 Note that the above example is
4610 L<strongly discouraged|DBIx::Class::ResultSource/resultset_attributes>.
4614 Set to 1 to cache search results. This prevents extra SQL queries if you
4615 revisit rows in your ResultSet:
4617 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4619 while( my $artist = $resultset->next ) {
4623 $resultset->first; # without cache, this would issue a query
4625 By default, searches are not cached.
4627 For more examples of using these attributes, see
4628 L<DBIx::Class::Manual::Cookbook>.
4634 =item Value: ( 'update' | 'shared' | \$scalar )
4638 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4639 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4644 DBIx::Class supports arbitrary related data prefetching from multiple related
4645 sources. Any combination of relationship types and column sets are supported.
4646 If L<collapsing|/collapse> is requested, there is an additional requirement of
4647 selecting enough data to make every individual object uniquely identifiable.
4649 Here are some more involved examples, based on the following relationship map:
4652 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4653 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4654 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4656 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4658 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4662 my $rs = $schema->resultset('Tag')->search(
4671 The initial search results in SQL like the following:
4673 SELECT tag.*, cd.*, artist.* FROM tag
4674 JOIN cd ON tag.cd = cd.cdid
4675 JOIN artist ON cd.artist = artist.artistid
4677 L<DBIx::Class> has no need to go back to the database when we access the
4678 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4681 Simple prefetches will be joined automatically, so there is no need
4682 for a C<join> attribute in the above search.
4684 The L</prefetch> attribute can be used with any of the relationship types
4685 and multiple prefetches can be specified together. Below is a more complex
4686 example that prefetches a CD's artist, its liner notes (if present),
4687 the cover image, the tracks on that CD, and the guests on those
4690 my $rs = $schema->resultset('CD')->search(
4694 { artist => 'record_label'}, # belongs_to => belongs_to
4695 'liner_note', # might_have
4696 'cover_image', # has_one
4697 { tracks => 'guests' }, # has_many => has_many
4702 This will produce SQL like the following:
4704 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4708 ON artist.artistid = me.artistid
4709 JOIN record_label record_label
4710 ON record_label.labelid = artist.labelid
4711 LEFT JOIN track tracks
4712 ON tracks.cdid = me.cdid
4713 LEFT JOIN guest guests
4714 ON guests.trackid = track.trackid
4715 LEFT JOIN liner_notes liner_note
4716 ON liner_note.cdid = me.cdid
4717 JOIN cd_artwork cover_image
4718 ON cover_image.cdid = me.cdid
4721 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4722 C<tracks>, and C<guests> of the CD will all be available through the
4723 relationship accessors without the need for additional queries to the
4728 Prefetch does a lot of deep magic. As such, it may not behave exactly
4729 as you might expect.
4735 Prefetch uses the L</cache> to populate the prefetched relationships. This
4736 may or may not be what you want.
4740 If you specify a condition on a prefetched relationship, ONLY those
4741 rows that match the prefetched condition will be fetched into that relationship.
4742 This means that adding prefetch to a search() B<may alter> what is returned by
4743 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4745 my $artist_rs = $schema->resultset('Artist')->search({
4751 my $count = $artist_rs->first->cds->count;
4753 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4755 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4757 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4759 That cmp_ok() may or may not pass depending on the datasets involved. In other
4760 words the C<WHERE> condition would apply to the entire dataset, just like
4761 it would in regular SQL. If you want to add a condition only to the "right side"
4762 of a C<LEFT JOIN> - consider declaring and using a L<relationship with a custom
4763 condition|DBIx::Class::Relationship::Base/condition>
4767 =head1 DBIC BIND VALUES
4769 Because DBIC may need more information to bind values than just the column name
4770 and value itself, it uses a special format for both passing and receiving bind
4771 values. Each bind value should be composed of an arrayref of
4772 C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
4778 If present (in any form), this is what is being passed directly to bind_param.
4779 Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
4780 a single numerical type, while DBD::Pg takes a hashref if bind options.)
4782 If this is specified, all other bind options described below are ignored.
4786 If present, this is used to infer the actual bind attribute by passing to
4787 C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
4788 "data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
4790 Note that the data type is somewhat freeform (hence the sqlt_ prefix);
4791 currently drivers are expected to "Do the Right Thing" when given a common
4792 datatype name. (Not ideal, but that's what we got at this point.)
4796 Currently used to correctly allocate buffers for bind_param_inout().
4797 Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
4798 or to a sensible value based on the "data_type".
4802 Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
4803 explicitly specified they are never overridden). Also used by some weird DBDs,
4804 where the column name should be available at bind_param time (e.g. Oracle).
4808 For backwards compatibility and convenience, the following shortcuts are
4811 [ $name => $val ] === [ { dbic_colname => $name }, $val ]
4812 [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
4813 [ undef, $val ] === [ {}, $val ]
4814 $val === [ {}, $val ]
4816 =head1 FURTHER QUESTIONS?
4818 Check the list of L<additional DBIC resources|DBIx::Class/GETTING HELP/SUPPORT>.
4820 =head1 COPYRIGHT AND LICENSE
4822 This module is free software L<copyright|DBIx::Class/COPYRIGHT AND LICENSE>
4823 by the L<DBIx::Class (DBIC) authors|DBIx::Class/AUTHORS>. You can
4824 redistribute it and/or modify it under the same terms as the
4825 L<DBIx::Class library|DBIx::Class/COPYRIGHT AND LICENSE>.