1 package DBIx::Class::ResultSet;
6 use base 'DBIx::Class';
9 use DBIx::Class::ResultSetColumn;
10 use DBIx::Class::ResultClass::HashRefInflator;
11 use Scalar::Util qw( blessed reftype );
12 use DBIx::Class::_Util qw(
13 dbic_internal_try dbic_internal_catch dump_value emit_loud_diag
14 fail_on_internal_wantarray fail_on_internal_call UNRESOLVABLE_CONDITION
16 use DBIx::Class::SQLMaker::Util qw( normalize_sqla_condition extract_equality_conditions );
19 # De-duplication in _merge_attr() is disabled, but left in for reference
20 # (the merger is used for other things that ought not to be de-duped)
21 *__HM_DEDUP = sub () { 0 };
31 # this is real - CDBICompat overrides it with insanity
32 # yes, prototype won't matter, but that's for now ;)
35 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class result_source/);
39 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
43 my $users_rs = $schema->resultset('User');
44 while( $user = $users_rs->next) {
45 print $user->username;
48 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
49 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
53 A ResultSet is an object which stores a set of conditions representing
54 a query. It is the backbone of DBIx::Class (i.e. the really
55 important/useful bit).
57 No SQL is executed on the database when a ResultSet is created, it
58 just stores all the conditions needed to create the query.
60 A basic ResultSet representing the data of an entire table is returned
61 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
62 L<Source|DBIx::Class::Manual::Glossary/ResultSource> name.
64 my $users_rs = $schema->resultset('User');
66 A new ResultSet is returned from calling L</search> on an existing
67 ResultSet. The new one will contain all the conditions of the
68 original, plus any new conditions added in the C<search> call.
70 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
71 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
74 The query that the ResultSet represents is B<only> executed against
75 the database when these methods are called:
76 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
78 If a resultset is used in a numeric context it returns the L</count>.
79 However, if it is used in a boolean context it is B<always> true. So if
80 you want to check if a resultset has any results, you must use C<if $rs
85 =head2 Chaining resultsets
87 Let's say you've got a query that needs to be run to return some data
88 to the user. But, you have an authorization system in place that
89 prevents certain users from seeing certain information. So, you want
90 to construct the basic query in one method, but add constraints to it in
95 my $request = $self->get_request; # Get a request object somehow.
96 my $schema = $self->result_source->schema;
98 my $cd_rs = $schema->resultset('CD')->search({
99 title => $request->param('title'),
100 year => $request->param('year'),
103 $cd_rs = $self->apply_security_policy( $cd_rs );
105 return $cd_rs->all();
108 sub apply_security_policy {
117 =head3 Resolving conditions and attributes
119 When a resultset is chained from another resultset (e.g.:
120 C<< my $new_rs = $old_rs->search(\%extra_cond, \%attrs) >>), conditions
121 and attributes with the same keys need resolving.
123 If any of L</columns>, L</select>, L</as> are present, they reset the
124 original selection, and start the selection "clean".
126 The L</join>, L</prefetch>, L</+columns>, L</+select>, L</+as> attributes
127 are merged into the existing ones from the original resultset.
129 The L</where> and L</having> attributes, and any search conditions, are
130 merged with an SQL C<AND> to the existing condition from the original
133 All other attributes are overridden by any new ones supplied in the
136 =head2 Multiple queries
138 Since a resultset just defines a query, you can do all sorts of
139 things with it with the same object.
141 # Don't hit the DB yet.
142 my $cd_rs = $schema->resultset('CD')->search({
143 title => 'something',
147 # Each of these hits the DB individually.
148 my $count = $cd_rs->count;
149 my $most_recent = $cd_rs->get_column('date_released')->max();
150 my @records = $cd_rs->all;
152 And it's not just limited to SELECT statements.
158 $cd_rs->create({ artist => 'Fred' });
160 Which is the same as:
162 $schema->resultset('CD')->create({
163 title => 'something',
168 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
170 =head2 Custom ResultSet classes
172 To add methods to your resultsets, you can subclass L<DBIx::Class::ResultSet>, similar to:
174 package MyApp::Schema::ResultSet::User;
179 use base 'DBIx::Class::ResultSet';
183 $self->search({ $self->current_source_alias . '.active' => 1 });
188 $self->search({ $self->current_source_alias . '.verified' => 0 });
191 sub created_n_days_ago {
192 my ($self, $days_ago) = @_;
194 $self->current_source_alias . '.create_date' => {
196 $self->result_source->schema->storage->datetime_parser->format_datetime(
197 DateTime->now( time_zone => 'UTC' )->subtract( days => $days_ago )
202 sub users_to_warn { shift->active->unverified->created_n_days_ago(7) }
206 See L<DBIx::Class::Schema/load_namespaces> on how DBIC can discover and
207 automatically attach L<Result|DBIx::Class::Manual::ResultClass>-specific
208 L<ResulSet|DBIx::Class::ResultSet> classes.
210 =head3 ResultSet subclassing with Moose and similar constructor-providers
212 Using L<Moose> or L<Moo> in your ResultSet classes is usually overkill, but
213 you may find it useful if your ResultSets contain a lot of business logic
214 (e.g. C<has xml_parser>, C<has json>, etc) or if you just prefer to organize
217 In order to write custom ResultSet classes with L<Moo> you need to use the
218 following template. The L<BUILDARGS|Moo/BUILDARGS> is necessary due to the
219 unusual signature of the L<constructor provided by DBIC
220 |DBIx::Class::ResultSet/new> C<< ->new($source, \%args) >>.
223 extends 'DBIx::Class::ResultSet';
224 sub BUILDARGS { $_[2] } # ::RS::new() expects my ($class, $rsrc, $args) = @_
230 If you want to build your custom ResultSet classes with L<Moose>, you need
231 a similar, though a little more elaborate template in order to interface the
232 inlining of the L<Moose>-provided
233 L<object constructor|Moose::Manual::Construction/WHERE'S THE CONSTRUCTOR?>,
236 package MyApp::Schema::ResultSet::User;
239 use MooseX::NonMoose;
240 extends 'DBIx::Class::ResultSet';
242 sub BUILDARGS { $_[2] } # ::RS::new() expects my ($class, $rsrc, $args) = @_
246 __PACKAGE__->meta->make_immutable;
250 The L<MooseX::NonMoose> is necessary so that the L<Moose> constructor does not
251 entirely overwrite the DBIC one (in contrast L<Moo> does this automatically).
252 Alternatively, you can skip L<MooseX::NonMoose> and get by with just L<Moose>
255 __PACKAGE__->meta->make_immutable(inline_constructor => 0);
263 =item Arguments: L<$source|DBIx::Class::ResultSource>, L<\%attrs?|/ATTRIBUTES>
265 =item Return Value: L<$resultset|/search>
269 The resultset constructor. Takes a source object (usually a
270 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
271 L</ATTRIBUTES> below). Does not perform any queries -- these are
272 executed as needed by the other methods.
274 Generally you never construct a resultset manually. Instead you get one
276 C<< $schema->L<resultset|DBIx::Class::Schema/resultset>('$source_name') >>
277 or C<< $another_resultset->L<search|/search>(...) >> (the later called in
280 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
286 If called on an object, proxies to L</new_result> instead, so
288 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
290 will return a CD object, not a ResultSet, and is equivalent to:
292 my $cd = $schema->resultset('CD')->new_result({ title => 'Spoon' });
294 Please also keep in mind that many internals call L</new_result> directly,
295 so overloading this method with the idea of intercepting new result object
296 creation B<will not work>. See also warning pertaining to L</create>.
306 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
307 return $class->new_result(@_);
310 my ($source, $attrs) = @_;
311 $source = $source->resolve
312 if $source->isa('DBIx::Class::ResultSourceHandle');
314 $attrs = { %{$attrs||{}} };
315 delete @{$attrs}{qw(_last_sqlmaker_alias_map _simple_passthrough_construction)};
317 if ($attrs->{page}) {
318 $attrs->{rows} ||= 10;
321 $attrs->{alias} ||= 'me';
324 result_source => $source,
325 cond => $attrs->{where},
330 # if there is a dark selector, this means we are already in a
331 # chain and the cleanup/sanification was taken care of by
333 $self->_normalize_selection($attrs)
334 unless $attrs->{_dark_selector};
337 $attrs->{result_class} || $source->result_class
347 =item Arguments: L<$cond|DBIx::Class::SQLMaker> | undef, L<\%attrs?|/ATTRIBUTES>
349 =item Return Value: $resultset (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
353 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
354 my $new_rs = $cd_rs->search({ year => 2005 });
356 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
357 # year = 2005 OR year = 2004
359 In list context, C<< ->all() >> is called implicitly on the resultset, thus
360 returning a list of L<result|DBIx::Class::Manual::ResultClass> objects instead.
361 To avoid that, use L</search_rs>.
363 If you need to pass in additional attributes but no additional condition,
364 call it as C<search(undef, \%attrs)>.
366 # "SELECT name, artistid FROM $artist_table"
367 my @all_artists = $schema->resultset('Artist')->search(undef, {
368 columns => [qw/name artistid/],
371 For a list of attributes that can be passed to C<search>, see
372 L</ATTRIBUTES>. For more examples of using this function, see
373 L<Searching|DBIx::Class::Manual::Cookbook/SEARCHING>. For a complete
374 documentation for the first argument, see L<SQL::Abstract/"WHERE CLAUSES">
375 and its extension L<DBIx::Class::SQLMaker>.
377 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
381 Note that L</search> does not process/deflate any of the values passed in the
382 L<SQL::Abstract>-compatible search condition structure. This is unlike other
383 condition-bound methods L</new_result>, L</create> and L</find>. The user must ensure
384 manually that any value passed to this method will stringify to something the
385 RDBMS knows how to deal with. A notable example is the handling of L<DateTime>
386 objects, for more info see:
387 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
393 my $rs = $self->search_rs( @_ );
396 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_WANTARRAY and my $sog = fail_on_internal_wantarray;
399 elsif (defined wantarray) {
403 # we can be called by a relationship helper, which in
404 # turn may be called in void context due to some braindead
405 # overload or whatever else the user decided to be clever
406 # at this particular day. Thus limit the exception to
407 # external code calls only
408 $self->throw_exception ('->search is *not* a mutator, calling it in void context makes no sense')
409 if (caller)[0] !~ /^\QDBIx::Class::/;
419 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
421 =item Return Value: L<$resultset|/search>
425 This method does the same exact thing as search() except it will
426 always return a resultset, even in list context.
433 my $rsrc = $self->result_source;
434 my ($call_cond, $call_attrs);
436 # Special-case handling for (undef, undef) or (undef)
437 # Note that (foo => undef) is valid deprecated syntax
438 @_ = () if not scalar grep { defined $_ } @_;
444 # fish out attrs in the ($condref, $attr) case
445 elsif (@_ == 2 and ( ! defined $_[0] or length ref $_[0] ) ) {
446 ($call_cond, $call_attrs) = @_;
449 $self->throw_exception('Odd number of arguments to search')
453 carp_unique 'search( %condition ) is deprecated, use search( \%condition ) instead'
454 unless $rsrc->result_class->isa('DBIx::Class::CDBICompat');
456 for my $i (0 .. $#_) {
458 $self->throw_exception ('All keys in condition key/value pairs must be plain scalars')
459 if (! defined $_[$i] or length ref $_[$i] );
465 # see if we can keep the cache (no $rs changes)
467 my %safe = (alias => 1, cache => 1);
468 if ( ! grep { !$safe{$_} } keys %$call_attrs and (
471 ref $call_cond eq 'HASH' && ! keys %$call_cond
473 ref $call_cond eq 'ARRAY' && ! @$call_cond
475 $cache = $self->get_cache;
478 my $old_attrs = { %{$self->{attrs}} };
479 my ($old_having, $old_where) = delete @{$old_attrs}{qw(having where)};
481 my $new_attrs = { %$old_attrs };
483 # take care of call attrs (only if anything is changing)
484 if ($call_attrs and keys %$call_attrs) {
486 # copy for _normalize_selection
487 $call_attrs = { %$call_attrs };
489 my @selector_attrs = qw/select as columns cols +select +as +columns include_columns/;
491 # reset the current selector list if new selectors are supplied
492 delete @{$old_attrs}{(@selector_attrs, '_dark_selector')}
493 if grep { exists $call_attrs->{$_} } qw(columns cols select as);
495 # Normalize the new selector list (operates on the passed-in attr structure)
496 # Need to do it on every chain instead of only once on _resolved_attrs, in
497 # order to allow detection of empty vs partial 'as'
498 $call_attrs->{_dark_selector} = $old_attrs->{_dark_selector}
499 if $old_attrs->{_dark_selector};
500 $self->_normalize_selection ($call_attrs);
502 # start with blind overwriting merge, exclude selector attrs
503 $new_attrs = { %{$old_attrs}, %{$call_attrs} };
504 delete @{$new_attrs}{@selector_attrs};
506 for (@selector_attrs) {
507 $new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
508 if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
511 # older deprecated name, use only if {columns} is not there
512 if (my $c = delete $new_attrs->{cols}) {
513 carp_unique( "Resultset attribute 'cols' is deprecated, use 'columns' instead" );
514 if ($new_attrs->{columns}) {
515 carp "Resultset specifies both the 'columns' and the legacy 'cols' attributes - ignoring 'cols'";
518 $new_attrs->{columns} = $c;
523 # join/prefetch use their own crazy merging heuristics
524 foreach my $key (qw/join prefetch/) {
525 $new_attrs->{$key} = $self->_merge_joinpref_attr($old_attrs->{$key}, $call_attrs->{$key})
526 if exists $call_attrs->{$key};
529 # stack binds together
530 $new_attrs->{bind} = [ @{ $old_attrs->{bind} || [] }, @{ $call_attrs->{bind} || [] } ];
534 for ($old_where, $call_cond) {
536 $new_attrs->{where} = $self->_stack_cond (
537 $_, $new_attrs->{where}
542 if (defined $old_having) {
543 $new_attrs->{having} = $self->_stack_cond (
544 $old_having, $new_attrs->{having}
548 my $rs = (ref $self)->new($rsrc, $new_attrs);
550 $rs->set_cache($cache) if ($cache);
555 sub _normalize_selection {
556 my ($self, $attrs) = @_;
559 if ( exists $attrs->{include_columns} ) {
560 carp_unique( "Resultset attribute 'include_columns' is deprecated, use '+columns' instead" );
561 $attrs->{'+columns'} = $self->_merge_attr(
562 $attrs->{'+columns'}, delete $attrs->{include_columns}
566 # columns are always placed first, however
568 # Keep the X vs +X separation until _resolved_attrs time - this allows to
569 # delay the decision on whether to use a default select list ($rsrc->columns)
570 # allowing stuff like the remove_columns helper to work
572 # select/as +select/+as pairs need special handling - the amount of select/as
573 # elements in each pair does *not* have to be equal (think multicolumn
574 # selectors like distinct(foo, bar) ). If the selector is bare (no 'as'
575 # supplied at all) - try to infer the alias, either from the -as parameter
576 # of the selector spec, or use the parameter whole if it looks like a column
577 # name (ugly legacy heuristic). If all fails - leave the selector bare (which
578 # is ok as well), but make sure no more additions to the 'as' chain take place
579 for my $pref ('', '+') {
581 my ($sel, $as) = map {
582 my $key = "${pref}${_}";
584 my $val = [ ref $attrs->{$key} eq 'ARRAY'
586 : $attrs->{$key} || ()
588 delete $attrs->{$key};
592 if (! @$as and ! @$sel ) {
595 elsif (@$as and ! @$sel) {
596 $self->throw_exception(
597 "Unable to handle ${pref}as specification (@$as) without a corresponding ${pref}select"
601 # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
602 # if any @$as has been supplied we assume the user knows what (s)he is doing
603 # and blindly keep stacking up pieces
604 unless ($attrs->{_dark_selector}) {
607 if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
608 push @$as, $_->{-as};
610 # assume any plain no-space, no-parenthesis string to be a column spec
611 # FIXME - this is retarded but is necessary to support shit like 'count(foo)'
612 elsif ( ! ref $_ and $_ =~ /^ [^\s\(\)]+ $/x) {
615 # if all else fails - raise a flag that no more aliasing will be allowed
617 $attrs->{_dark_selector} = {
620 local $Data::Dumper::Indent = 0;
629 elsif (@$as < @$sel) {
630 $self->throw_exception(
631 "Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
634 elsif ($pref and $attrs->{_dark_selector}) {
635 $self->throw_exception(
636 "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
642 $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
643 $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
648 my ($self, $left, $right) = @_;
651 (ref $_ eq 'ARRAY' and !@$_)
653 (ref $_ eq 'HASH' and ! keys %$_)
654 ) and $_ = undef for ($left, $right);
657 # either one of the two undef
658 ( (defined $left) xor (defined $right) ) ? ( defined $left ? $left : $right )
661 : ( ! defined $left ) ? undef
663 : { -and => [$left, $right] }
667 =head2 search_literal
669 B<CAVEAT>: C<search_literal> is provided for Class::DBI compatibility and
670 should only be used in that context. C<search_literal> is a convenience
671 method. It is equivalent to calling C<< $schema->search(\[]) >>, but if you
672 want to ensure columns are bound correctly, use L</search>.
674 See L<DBIx::Class::Manual::Cookbook/SEARCHING> and
675 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
676 require C<search_literal>.
680 =item Arguments: $sql_fragment, @standalone_bind_values
682 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
686 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
687 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
689 Pass a literal chunk of SQL to be added to the conditional part of the
692 Example of how to use C<search> instead of C<search_literal>
694 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
695 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
700 my ($self, $sql, @bind) = @_;
702 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
705 return $self->search(\[ $sql, map [ {} => $_ ], @bind ], ($attr || () ));
712 =item Arguments: \%columns_values | @pk_values, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
714 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
718 Finds and returns a single row based on supplied criteria. Takes either a
719 hashref with the same format as L</create> (including inference of foreign
720 keys from related objects), or a list of primary key values in the same
721 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
722 declaration on the L</result_source>.
724 In either case an attempt is made to combine conditions already existing on
725 the resultset with the condition passed to this method.
727 To aid with preparing the correct query for the storage you may supply the
728 C<key> attribute, which is the name of a
729 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
730 unique constraint corresponding to the
731 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
732 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
733 to construct a query that satisfies the named unique constraint fully (
734 non-NULL values for each column member of the constraint) an exception is
737 If no C<key> is specified, the search is carried over all unique constraints
738 which are fully defined by the available condition.
740 If no such constraint is found, C<find> currently defaults to a simple
741 C<< search->(\%column_values) >> which may or may not do what you expect.
742 Note that this fallback behavior may be deprecated in further versions. If
743 you need to search with arbitrary conditions - use L</search>. If the query
744 resulting from this fallback produces more than one row, a warning to the
745 effect is issued, though only the first row is constructed and returned as
748 In addition to C<key>, L</find> recognizes and applies standard
749 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
751 Note that if you have extra concerns about the correctness of the resulting
752 query you need to specify the C<key> attribute and supply the entire condition
753 as an argument to find (since it is not always possible to perform the
754 combination of the resultset condition with the supplied one, especially if
755 the resultset condition contains literal sql).
757 For example, to find a row by its primary key:
759 my $cd = $schema->resultset('CD')->find(5);
761 You can also find a row by a specific unique constraint:
763 my $cd = $schema->resultset('CD')->find(
765 artist => 'Massive Attack',
766 title => 'Mezzanine',
768 { key => 'cd_artist_title' }
771 See also L</find_or_create> and L</update_or_create>.
777 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
779 my $rsrc = $self->result_source;
782 if (exists $attrs->{key}) {
783 $constraint_name = defined $attrs->{key}
785 : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
789 # Parse out the condition from input
792 if (ref $_[0] eq 'HASH') {
793 $call_cond = { %{$_[0]} };
796 # if only values are supplied we need to default to 'primary'
797 $constraint_name = 'primary' unless defined $constraint_name;
799 my @c_cols = $rsrc->unique_constraint_columns($constraint_name);
801 $self->throw_exception(
802 "No constraint columns, maybe a malformed '$constraint_name' constraint?"
805 $self->throw_exception (
806 'find() expects either a column/value hashref, or a list of values '
807 . "corresponding to the columns of the specified unique constraint '$constraint_name'"
808 ) unless @c_cols == @_;
810 @{$call_cond}{@c_cols} = @_;
813 # process relationship data if any
814 for my $key (keys %$call_cond) {
816 length ref($call_cond->{$key})
818 my $relinfo = $rsrc->relationship_info($key)
820 # implicitly skip has_many's (likely MC)
821 ( ref( my $val = delete $call_cond->{$key} ) ne 'ARRAY' )
823 my ($rel_cond, $crosstable) = $rsrc->_resolve_condition(
824 $relinfo->{cond}, $val, $key, $key
827 $self->throw_exception("Complex condition via relationship '$key' is unsupported in find()")
828 if $crosstable or ref($rel_cond) ne 'HASH';
830 # supplement condition
831 # relationship conditions take precedence (?)
832 @{$call_cond}{keys %$rel_cond} = values %$rel_cond;
836 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
838 if (defined $constraint_name) {
839 $final_cond = $self->_qualify_cond_columns (
841 $rsrc->_minimal_valueset_satisfying_constraint(
842 constraint_name => $constraint_name,
843 values => ($self->_merge_with_rscond($call_cond))[0],
850 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
851 # This means that we got here after a merger of relationship conditions
852 # in ::Relationship::Base::search_related (the row method), and furthermore
853 # the relationship is of the 'single' type. This means that the condition
854 # provided by the relationship (already attached to $self) is sufficient,
855 # as there can be only one row in the database that would satisfy the
859 my (@unique_queries, %seen_column_combinations, $ci, @fc_exceptions);
861 # no key was specified - fall down to heuristics mode:
862 # run through all unique queries registered on the resultset, and
863 # 'OR' all qualifying queries together
865 # always start from 'primary' if it exists at all
866 for my $c_name ( sort {
868 : $b eq 'primary' ? 1
870 } $rsrc->unique_constraint_names) {
872 next if $seen_column_combinations{
873 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
877 push @unique_queries, $self->_qualify_cond_columns(
878 $rsrc->_minimal_valueset_satisfying_constraint(
879 constraint_name => $c_name,
880 values => ($self->_merge_with_rscond($call_cond))[0],
881 columns_info => ($ci ||= $rsrc->columns_info),
886 dbic_internal_catch {
887 push @fc_exceptions, $_ if $_ =~ /\bFilterColumn\b/;
892 @unique_queries ? \@unique_queries
893 : @fc_exceptions ? $self->throw_exception(join "; ", map { $_ =~ /(.*) at .+ line \d+$/s } @fc_exceptions )
894 : $self->_non_unique_find_fallback ($call_cond, $attrs)
898 # Run the query, passing the result_class since it should propagate for find
899 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
900 if ($rs->_resolved_attrs->{collapse}) {
902 carp "Query returned more than one row" if $rs->next;
910 # This is a stop-gap method as agreed during the discussion on find() cleanup:
911 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
913 # It is invoked when find() is called in legacy-mode with insufficiently-unique
914 # condition. It is provided for overrides until a saner way forward is devised
916 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
917 # the road. Please adjust your tests accordingly to catch this situation early
918 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
920 # The method will not be removed without an adequately complete replacement
921 # for strict-mode enforcement
922 sub _non_unique_find_fallback {
923 my ($self, $cond, $attrs) = @_;
925 return $self->_qualify_cond_columns(
927 exists $attrs->{alias}
929 : $self->{attrs}{alias}
934 sub _qualify_cond_columns {
935 my ($self, $cond, $alias) = @_;
937 my %aliased = %$cond;
938 for (keys %aliased) {
939 $aliased{"$alias.$_"} = delete $aliased{$_}
946 sub _build_unique_cond {
948 '_build_unique_cond is a private method, and moreover is about to go '
949 . 'away. Please contact the development team at %s if you believe you '
950 . 'have a genuine use for this method, in order to discuss alternatives.',
951 DBIx::Class::_ENV_::HELP_URL,
954 my ($self, $constraint_name, $cond, $croak_on_null) = @_;
956 $self->result_source->_minimal_valueset_satisfying_constraint(
957 constraint_name => $constraint_name,
959 carp_on_nulls => !$croak_on_null
963 =head2 search_related
967 =item Arguments: $rel_name, $cond?, L<\%attrs?|/ATTRIBUTES>
969 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
973 $new_rs = $cd_rs->search_related('artist', {
977 Searches the specified relationship, optionally specifying a condition and
978 attributes for matching records. See L</ATTRIBUTES> for more information.
980 In list context, C<< ->all() >> is called implicitly on the resultset, thus
981 returning a list of result objects instead. To avoid that, use L</search_related_rs>.
983 See also L</search_related_rs>.
987 sub search_related :DBIC_method_is_indirect_sugar {
988 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
989 return shift->related_resultset(shift)->search(@_);
992 =head2 search_related_rs
994 This method works exactly the same as search_related, except that
995 it guarantees a resultset, even in list context.
999 sub search_related_rs :DBIC_method_is_indirect_sugar {
1000 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1001 return shift->related_resultset(shift)->search_rs(@_);
1008 =item Arguments: none
1010 =item Return Value: L<$cursor|DBIx::Class::Cursor>
1014 Returns a storage-driven cursor to the given resultset. See
1015 L<DBIx::Class::Cursor> for more information.
1022 return $self->{cursor} ||= do {
1023 my $attrs = $self->_resolved_attrs;
1024 $self->result_source->schema->storage->select(
1025 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
1034 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1036 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1040 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1042 Inflates the first result without creating a cursor if the resultset has
1043 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1046 While this method can take an optional search condition (just like L</search>)
1047 being a fast-code-path it does not recognize search attributes. If you need to
1048 add extra joins or similar, call L</search> and then chain-call L</single> on the
1049 L<DBIx::Class::ResultSet> returned.
1055 As of 0.08100, this method enforces the assumption that the preceding
1056 query returns only one row. If more than one row is returned, you will receive
1059 Query returned more than one row
1061 In this case, you should be using L</next> or L</find> instead, or if you really
1062 know what you are doing, use the L</rows> attribute to explicitly limit the size
1065 This method will also throw an exception if it is called on a resultset prefetching
1066 has_many, as such a prefetch implies fetching multiple rows from the database in
1067 order to assemble the resulting object.
1074 my ($self, $where) = @_;
1076 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1079 my $attrs = { %{$self->_resolved_attrs} };
1081 $self->throw_exception(
1082 'single() can not be used on resultsets collapsing a has_many. Use find( \%cond ) or next() instead'
1083 ) if $attrs->{collapse};
1086 if (defined $attrs->{where}) {
1089 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1090 $where, delete $attrs->{where} ]
1093 $attrs->{where} = $where;
1097 my $data = [ $self->result_source->schema->storage->select_single(
1098 $attrs->{from}, $attrs->{select},
1099 $attrs->{where}, $attrs
1102 return undef unless @$data;
1103 $self->{_stashed_rows} = [ $data ];
1104 $self->_construct_results->[0];
1111 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1113 =item Return Value: L<$resultsetcolumn|DBIx::Class::ResultSetColumn>
1117 my $max_length = $rs->get_column('length')->max;
1119 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1124 DBIx::Class::ResultSetColumn->new(@_);
1131 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1133 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1137 # WHERE title LIKE '%blue%'
1138 $cd_rs = $rs->search_like({ title => '%blue%'});
1140 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1141 that this is simply a convenience method retained for ex Class::DBI users.
1142 You most likely want to use L</search> with specific operators.
1144 For more information, see L<DBIx::Class::Manual::Cookbook>.
1146 This method is deprecated and will be removed in 0.09. Use L<search()|/search>
1147 instead. An example conversion is:
1149 ->search_like({ foo => 'bar' });
1153 ->search({ foo => { like => 'bar' } });
1160 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1161 .' Instead use ->search({ x => { -like => "y%" } })'
1162 .' (note the outer pair of {}s - they are important!)'
1164 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
1165 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1166 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1167 return $class->search($query, { %$attrs });
1174 =item Arguments: $first, $last
1176 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1180 Returns a resultset or object list representing a subset of elements from the
1181 resultset slice is called on. Indexes are from 0, i.e., to get the first
1182 three records, call:
1184 my ($one, $two, $three) = $rs->slice(0, 2);
1189 my ($self, $min, $max) = @_;
1190 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1191 $attrs->{offset} = $self->{attrs}{offset} || 0;
1192 $attrs->{offset} += $min;
1193 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1194 return $self->search(undef, $attrs);
1201 =item Arguments: none
1203 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1207 Returns the next element in the resultset (C<undef> is there is none).
1209 Can be used to efficiently iterate over records in the resultset:
1211 my $rs = $schema->resultset('CD')->search;
1212 while (my $cd = $rs->next) {
1216 Note that you need to store the resultset object, and call C<next> on it.
1217 Calling C<< resultset('Table')->next >> repeatedly will always return the
1218 first record from the resultset.
1225 if (my $cache = $self->get_cache) {
1226 $self->{all_cache_position} ||= 0;
1227 return $cache->[$self->{all_cache_position}++];
1230 if ($self->{attrs}{cache}) {
1231 delete $self->{pager};
1232 $self->{all_cache_position} = 1;
1233 return ($self->all)[0];
1236 return shift(@{$self->{_stashed_results}}) if @{ $self->{_stashed_results}||[] };
1238 $self->{_stashed_results} = $self->_construct_results
1241 return shift @{$self->{_stashed_results}};
1244 # Constructs as many results as it can in one pass while respecting
1245 # cursor laziness. Several modes of operation:
1247 # * Always builds everything present in @{$self->{_stashed_rows}}
1248 # * If called with $fetch_all true - pulls everything off the cursor and
1249 # builds all result structures (or objects) in one pass
1250 # * If $self->_resolved_attrs->{collapse} is true, checks the order_by
1251 # and if the resultset is ordered properly by the left side:
1252 # * Fetches stuff off the cursor until the "master object" changes,
1253 # and saves the last extra row (if any) in @{$self->{_stashed_rows}}
1255 # * Just fetches, and collapses/constructs everything as if $fetch_all
1256 # was requested (there is no other way to collapse except for an
1258 # * If no collapse is requested - just get the next row, construct and
1260 sub _construct_results {
1261 my ($self, $fetch_all) = @_;
1263 my $rsrc = $self->result_source;
1264 my $attrs = $self->_resolved_attrs;
1269 ! $attrs->{order_by}
1273 my @pcols = $rsrc->primary_columns
1275 # default order for collapsing unless the user asked for something
1276 $attrs->{order_by} = [ map { join '.', $attrs->{alias}, $_} @pcols ];
1277 $attrs->{_ordered_for_collapse} = 1;
1278 $attrs->{_order_is_artificial} = 1;
1281 # this will be used as both initial raw-row collector AND as a RV of
1282 # _construct_results. Not regrowing the array twice matters a lot...
1283 # a surprising amount actually
1284 my $rows = delete $self->{_stashed_rows};
1286 my $cursor; # we may not need one at all
1288 my $did_fetch_all = $fetch_all;
1291 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1292 $rows = [ ($rows ? @$rows : ()), $self->cursor->all ];
1294 elsif( $attrs->{collapse} ) {
1296 # a cursor will need to be closed over in case of collapse
1297 $cursor = $self->cursor;
1299 $attrs->{_ordered_for_collapse} = (
1305 ->_extract_colinfo_of_stable_main_source_order_by_portion($attrs)
1307 ) unless defined $attrs->{_ordered_for_collapse};
1309 if (! $attrs->{_ordered_for_collapse}) {
1312 # instead of looping over ->next, use ->all in stealth mode
1313 # *without* calling a ->reset afterwards
1314 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1315 if (! $cursor->{_done}) {
1316 $rows = [ ($rows ? @$rows : ()), $cursor->all ];
1317 $cursor->{_done} = 1;
1322 if (! $did_fetch_all and ! @{$rows||[]} ) {
1323 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1324 $cursor ||= $self->cursor;
1325 if (scalar (my @r = $cursor->next) ) {
1330 return undef unless @{$rows||[]};
1332 # sanity check - people are too clever for their own good
1333 if ($attrs->{collapse} and my $aliastypes = $attrs->{_last_sqlmaker_alias_map} ) {
1335 my $multiplied_selectors;
1336 for my $sel_alias ( grep { $_ ne $attrs->{alias} } keys %{ $aliastypes->{selecting} } ) {
1338 $aliastypes->{multiplying}{$sel_alias}
1340 $aliastypes->{premultiplied}{$sel_alias}
1342 $multiplied_selectors->{$_} = 1 for values %{$aliastypes->{selecting}{$sel_alias}{-seen_columns}}
1346 for my $i (0 .. $#{$attrs->{as}} ) {
1347 my $sel = $attrs->{select}[$i];
1349 if (ref $sel eq 'SCALAR') {
1352 elsif( ref $sel eq 'REF' and ref $$sel eq 'ARRAY' ) {
1356 $self->throw_exception(
1357 'Result collapse not possible - selection from a has_many source redirected to the main object'
1358 ) if ($multiplied_selectors->{$sel} and $attrs->{as}[$i] !~ /\./);
1362 # hotspot - skip the setter
1363 my $res_class = $self->_result_class;
1365 my $inflator_cref = $self->{_result_inflator}{cref} ||= do {
1366 $res_class->can ('inflate_result')
1367 or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
1370 my $infmap = $attrs->{as};
1372 $self->{_result_inflator}{is_core_row} = ( (
1375 ( \&DBIx::Class::Row::inflate_result || die "No ::Row::inflate_result() - can't happen" )
1376 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_core_row};
1378 $self->{_result_inflator}{is_hri} = ( (
1379 ! $self->{_result_inflator}{is_core_row}
1381 $inflator_cref == \&DBIx::Class::ResultClass::HashRefInflator::inflate_result
1382 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_hri};
1385 if ($attrs->{_simple_passthrough_construction}) {
1386 # construct a much simpler array->hash folder for the one-table HRI cases right here
1387 if ($self->{_result_inflator}{is_hri}) {
1388 for my $r (@$rows) {
1389 $r = { map { $infmap->[$_] => $r->[$_] } 0..$#$infmap };
1392 # FIXME SUBOPTIMAL this is a very very very hot spot
1393 # while rather optimal we can *still* do much better, by
1394 # building a smarter Row::inflate_result(), and
1395 # switch to feeding it data via a much leaner interface
1397 # crude unscientific benchmarking indicated the shortcut eval is not worth it for
1398 # this particular resultset size
1399 elsif ( $self->{_result_inflator}{is_core_row} and @$rows < 60 ) {
1400 for my $r (@$rows) {
1401 $r = $inflator_cref->($res_class, $rsrc, { map { $infmap->[$_] => $r->[$_] } (0..$#$infmap) } );
1406 ( $self->{_result_inflator}{is_core_row}
1407 ? '$_ = $inflator_cref->($res_class, $rsrc, { %s }) for @$rows'
1408 # a custom inflator may be a multiplier/reductor - put it in direct list ctx
1409 : '@$rows = map { $inflator_cref->($res_class, $rsrc, { %s } ) } @$rows'
1411 ( join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap ) )
1417 $self->{_result_inflator}{is_hri} ? 'hri'
1418 : $self->{_result_inflator}{is_core_row} ? 'classic_pruning'
1419 : 'classic_nonpruning'
1422 unless( $self->{_row_parser}{$parser_type}{cref} ) {
1424 # $args and $attrs to _mk_row_parser are separated to delineate what is
1425 # core collapser stuff and what is dbic $rs specific
1426 $self->{_row_parser}{$parser_type}{src} = $rsrc->_mk_row_parser({
1427 inflate_map => $infmap,
1428 collapse => $attrs->{collapse},
1429 premultiplied => $attrs->{_main_source_premultiplied},
1430 hri_style => $self->{_result_inflator}{is_hri},
1431 prune_null_branches => $self->{_result_inflator}{is_hri} || $self->{_result_inflator}{is_core_row},
1434 $self->{_row_parser}{$parser_type}{cref} = do {
1435 package # hide form PAUSE
1436 DBIx::Class::__GENERATED_ROW_PARSER__;
1438 eval $self->{_row_parser}{$parser_type}{src};
1442 # this needs to close over the *current* cursor, hence why it is not cached above
1443 my $next_cref = ($did_fetch_all or ! $attrs->{collapse})
1446 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1447 my @r = $cursor->next or return;
1452 $self->{_row_parser}{$parser_type}{cref}->(
1455 ( $self->{_stashed_rows} = [] ),
1456 ( my $null_violations = {} ),
1459 $self->throw_exception(
1460 'Collapse aborted - the following columns are declared (or defaulted to) '
1461 . 'non-nullable within DBIC but NULLs were retrieved from storage: '
1462 . join( ', ', map { "'$infmap->[$_]'" } sort { $a <=> $b } keys %$null_violations )
1463 . ' within data row ' . dump_value({
1466 ( ! defined $self->{_stashed_rows}[0][$_] or length $self->{_stashed_rows}[0][$_] < 50 )
1467 ? $self->{_stashed_rows}[0][$_]
1468 : substr( $self->{_stashed_rows}[0][$_], 0, 50 ) . '...'
1469 } 0 .. $#{$self->{_stashed_rows}[0]}
1471 ) if keys %$null_violations;
1473 # simple in-place substitution, does not regrow $rows
1474 if ($self->{_result_inflator}{is_core_row}) {
1475 $_ = $inflator_cref->($res_class, $rsrc, @$_) for @$rows
1477 # Special-case multi-object HRI - there is no $inflator_cref pass at all
1478 elsif ( ! $self->{_result_inflator}{is_hri} ) {
1479 # the inflator may be a multiplier/reductor - put it in list ctx
1480 @$rows = map { $inflator_cref->($res_class, $rsrc, @$_) } @$rows;
1484 # The @$rows check seems odd at first - why wouldn't we want to warn
1485 # regardless? The issue is things like find() etc, where the user
1486 # *knows* only one result will come back. In these cases the ->all
1487 # is not a pessimization, but rather something we actually want
1489 'Unable to properly collapse has_many results in iterator mode due '
1490 . 'to order criteria - performed an eager cursor slurp underneath. '
1491 . 'Consider using ->all() instead'
1492 ) if ( ! $fetch_all and @$rows > 1 );
1497 =head2 result_source
1501 =item Arguments: L<$result_source?|DBIx::Class::ResultSource>
1503 =item Return Value: L<$result_source|DBIx::Class::ResultSource>
1507 An accessor for the primary ResultSource object from which this ResultSet
1514 =item Arguments: $result_class?
1516 =item Return Value: $result_class
1520 An accessor for the class to use when creating result objects. Defaults to
1521 C<< result_source->result_class >> - which in most cases is the name of the
1522 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1524 Note that changing the result_class will also remove any components
1525 that were originally loaded in the source class via
1526 L<load_components|Class::C3::Componentised/load_components( @comps )>.
1527 Any overloaded methods in the original source class will not run.
1532 my ($self, $result_class) = @_;
1533 if ($result_class) {
1535 # don't fire this for an object
1536 $self->ensure_class_loaded($result_class)
1537 unless ref($result_class);
1539 if ($self->get_cache) {
1540 carp_unique('Changing the result_class of a ResultSet instance with cached results is a noop - the cache contents will not be altered');
1542 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1543 elsif ($self->{cursor} && $self->{cursor}{_pos}) {
1544 $self->throw_exception('Changing the result_class of a ResultSet instance with an active cursor is not supported');
1547 $self->_result_class($result_class);
1549 delete $self->{_result_inflator};
1551 $self->_result_class;
1558 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1560 =item Return Value: $count
1564 Performs an SQL C<COUNT> with the same query as the resultset was built
1565 with to find the number of elements. Passing arguments is equivalent to
1566 C<< $rs->search ($cond, \%attrs)->count >>
1572 return $self->search(@_)->count if @_ and defined $_[0];
1573 return scalar @{ $self->get_cache } if $self->get_cache;
1575 my $attrs = { %{ $self->_resolved_attrs } };
1577 # this is a little optimization - it is faster to do the limit
1578 # adjustments in software, instead of a subquery
1579 my ($rows, $offset) = delete @{$attrs}{qw/rows offset/};
1582 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1583 $crs = $self->_count_subq_rs ($attrs);
1586 $crs = $self->_count_rs ($attrs);
1588 my $count = $crs->next;
1590 $count -= $offset if $offset;
1591 $count = $rows if $rows and $rows < $count;
1592 $count = 0 if ($count < 0);
1601 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1603 =item Return Value: L<$count_rs|DBIx::Class::ResultSetColumn>
1607 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1608 This can be very handy for subqueries:
1610 ->search( { amount => $some_rs->count_rs->as_query } )
1612 As with regular resultsets the SQL query will be executed only after
1613 the resultset is accessed via L</next> or L</all>. That would return
1614 the same single value obtainable via L</count>.
1620 return $self->search(@_)->count_rs if @_;
1622 # this may look like a lack of abstraction (count() does about the same)
1623 # but in fact an _rs *must* use a subquery for the limits, as the
1624 # software based limiting can not be ported if this $rs is to be used
1625 # in a subquery itself (i.e. ->as_query)
1626 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1627 return $self->_count_subq_rs($self->{_attrs});
1630 return $self->_count_rs($self->{_attrs});
1635 # returns a ResultSetColumn object tied to the count query
1638 my ($self, $attrs) = @_;
1640 my $rsrc = $self->result_source;
1642 my $tmp_attrs = { %$attrs };
1643 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1644 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1646 # overwrite the selector (supplied by the storage)
1647 $rsrc->resultset_class->new($rsrc, {
1649 select => $rsrc->schema->storage->_count_select ($rsrc, $attrs),
1651 })->get_column ('count');
1655 # same as above but uses a subquery
1657 sub _count_subq_rs {
1658 my ($self, $attrs) = @_;
1660 my $rsrc = $self->result_source;
1662 my $sub_attrs = { %$attrs };
1663 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1664 delete @{$sub_attrs}{qw/collapse columns as select order_by for/};
1666 # if we multi-prefetch we group_by something unique, as this is what we would
1667 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1668 if ( $attrs->{collapse} ) {
1669 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1670 $rsrc->_identifying_column_set || $self->throw_exception(
1671 'Unable to construct a unique group_by criteria properly collapsing the '
1672 . 'has_many prefetch before count()'
1677 # Calculate subquery selector
1678 if (my $g = $sub_attrs->{group_by}) {
1680 my $sql_maker = $rsrc->schema->storage->sql_maker;
1682 # necessary as the group_by may refer to aliased functions
1684 for my $sel (@{$attrs->{select}}) {
1685 $sel_index->{$sel->{-as}} = $sel
1686 if (ref $sel eq 'HASH' and $sel->{-as});
1689 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1690 # also look for named aggregates referred in the having clause
1691 # having often contains scalarrefs - thus parse it out entirely
1693 if ($attrs->{having}) {
1694 local $sql_maker->{having_bind};
1695 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1696 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1697 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1698 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1699 # if we don't unset it we screw up retarded but unfortunately working
1700 # 'MAX(foo.bar)' => { '>', 3 }
1701 $sql_maker->{name_sep} = '';
1704 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1706 my $having_sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1709 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1710 # and if all fails for an utterly naive quoted scalar-with-function
1711 while ($having_sql =~ /
1712 $rquote $sep $lquote (.+?) $rquote
1714 [\s,] \w+ \. (\w+) [\s,]
1716 [\s,] $lquote (.+?) $rquote [\s,]
1718 my $part = $1 || $2 || $3; # one of them matched if we got here
1719 unless ($seen_having{$part}++) {
1726 my $colpiece = $sel_index->{$_} || $_;
1728 # unqualify join-based group_by's. Arcane but possible query
1729 # also horrible horrible hack to alias a column (not a func.)
1730 # (probably need to introduce SQLA syntax)
1731 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1734 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1736 push @{$sub_attrs->{select}}, $colpiece;
1740 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1741 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1744 return $rsrc->resultset_class
1745 ->new ($rsrc, $sub_attrs)
1747 ->search ({}, { columns => { count => $rsrc->schema->storage->_count_select ($rsrc, $attrs) } })
1748 ->get_column ('count');
1752 =head2 count_literal
1754 B<CAVEAT>: C<count_literal> is provided for Class::DBI compatibility and
1755 should only be used in that context. See L</search_literal> for further info.
1759 =item Arguments: $sql_fragment, @standalone_bind_values
1761 =item Return Value: $count
1765 Counts the results in a literal query. Equivalent to calling L</search_literal>
1766 with the passed arguments, then L</count>.
1770 sub count_literal :DBIC_method_is_indirect_sugar {
1771 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1772 shift->search_literal(@_)->count
1779 =item Arguments: none
1781 =item Return Value: L<@result_objs|DBIx::Class::Manual::ResultClass>
1785 Returns all elements in the resultset.
1792 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1795 delete @{$self}{qw/_stashed_rows _stashed_results/};
1797 if (my $c = $self->get_cache) {
1801 $self->cursor->reset;
1803 my $objs = $self->_construct_results('fetch_all') || [];
1805 $self->set_cache($objs) if $self->{attrs}{cache};
1814 =item Arguments: none
1816 =item Return Value: $self
1820 Resets the resultset's cursor, so you can iterate through the elements again.
1821 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1829 delete @{$self}{qw/_stashed_rows _stashed_results/};
1830 $self->{all_cache_position} = 0;
1831 $self->cursor->reset;
1839 =item Arguments: none
1841 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1845 L<Resets|/reset> the resultset (causing a fresh query to storage) and returns
1846 an object for the first result (or C<undef> if the resultset is empty).
1850 sub first :DBIC_method_is_indirect_sugar {
1851 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1852 return $_[0]->reset->next;
1858 # Determines whether and what type of subquery is required for the $rs operation.
1859 # If grouping is necessary either supplies its own, or verifies the current one
1860 # After all is done delegates to the proper storage method.
1862 sub _rs_update_delete {
1863 my ($self, $op, $values) = @_;
1865 my $rsrc = $self->result_source;
1866 my $storage = $rsrc->schema->storage;
1868 my $attrs = { %{$self->_resolved_attrs} };
1870 my $join_classifications;
1871 my ($existing_group_by) = delete @{$attrs}{qw(group_by _grouped_by_distinct)};
1873 # do we need a subquery for any reason?
1875 defined $existing_group_by
1877 # if {from} is unparseable wrap a subq
1878 ref($attrs->{from}) ne 'ARRAY'
1880 # limits call for a subq
1881 $self->_has_resolved_attr(qw/rows offset/)
1884 # simplify the joinmap, so we can further decide if a subq is necessary
1885 if (!$needs_subq and @{$attrs->{from}} > 1) {
1887 ($attrs->{from}, $join_classifications) =
1888 $storage->_prune_unused_joins ($attrs);
1890 # any non-pruneable non-local restricting joins imply subq
1891 $needs_subq = grep { $_ ne $attrs->{alias} } keys %{ $join_classifications->{restricting} || {} };
1894 # check if the head is composite (by now all joins are thrown out unless $needs_subq)
1896 (ref $attrs->{from}[0]) ne 'HASH'
1898 ref $attrs->{from}[0]{ $attrs->{from}[0]{-alias} }
1902 # do we need anything like a subquery?
1903 if (! $needs_subq) {
1904 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1905 # a condition containing 'me' or other table prefixes will not work
1906 # at all. Tell SQLMaker to dequalify idents via a gross hack.
1908 my $sqla = $rsrc->schema->storage->sql_maker;
1909 local $sqla->{_dequalify_idents} = 1;
1910 \[ $sqla->_recurse_where($self->{cond}) ];
1914 # we got this far - means it is time to wrap a subquery
1915 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1917 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1923 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1924 delete $attrs->{$_} for qw/select as collapse/;
1925 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1927 # this will be consumed by the pruner waaaaay down the stack
1928 $attrs->{_force_prune_multiplying_joins} = 1;
1930 my $subrs = (ref $self)->new($rsrc, $attrs);
1932 if (@$idcols == 1) {
1933 $cond = { $idcols->[0] => { -in => $subrs->as_query } };
1935 elsif ($storage->_use_multicolumn_in) {
1936 # no syntax for calling this properly yet
1937 # !!! EXPERIMENTAL API !!! WILL CHANGE !!!
1938 $cond = $storage->sql_maker->_where_op_multicolumn_in (
1939 $idcols, # how do I convey a list of idents...? can binds reside on lhs?
1944 # if all else fails - get all primary keys and operate over a ORed set
1945 # wrap in a transaction for consistency
1946 # this is where the group_by/multiplication starts to matter
1950 # we do not need to check pre-multipliers, since if the premulti is there, its
1951 # parent (who is multi) will be there too
1952 keys %{ $join_classifications->{multiplying} || {} }
1954 # make sure if there is a supplied group_by it matches the columns compiled above
1955 # perfectly. Anything else can not be sanely executed on most databases so croak
1956 # right then and there
1957 if ($existing_group_by) {
1958 my @current_group_by = map
1959 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1964 join ("\x00", sort @current_group_by)
1966 join ("\x00", sort @{$attrs->{columns}} )
1968 $self->throw_exception (
1969 "You have just attempted a $op operation on a resultset which does group_by"
1970 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1971 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1972 . ' kind of queries. Please retry the operation with a modified group_by or'
1973 . ' without using one at all.'
1978 $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
1981 $guard = $storage->txn_scope_guard;
1983 for my $row ($subrs->cursor->all) {
1985 { $idcols->[$_] => $row->[$_] }
1992 my $res = $cond ? $storage->$op (
1994 $op eq 'update' ? $values : (),
1998 $guard->commit if $guard;
2007 =item Arguments: \%values
2009 =item Return Value: $underlying_storage_rv
2013 Sets the specified columns in the resultset to the supplied values in a
2014 single query. Note that this will not run any accessor/set_column/update
2015 triggers, nor will it update any result object instances derived from this
2016 resultset (this includes the contents of the L<resultset cache|/set_cache>
2017 if any). See L</update_all> if you need to execute any on-update
2018 triggers or cascades defined either by you or a
2019 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2021 The return value is a pass through of what the underlying
2022 storage backend returned, and may vary. See L<DBI/execute> for the most
2027 Note that L</update> does not process/deflate any of the values passed in.
2028 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
2029 ensure manually that any value passed to this method will stringify to
2030 something the RDBMS knows how to deal with. A notable example is the
2031 handling of L<DateTime> objects, for more info see:
2032 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
2037 my ($self, $values) = @_;
2038 $self->throw_exception('Values for update must be a hash')
2039 unless ref $values eq 'HASH';
2041 return $self->_rs_update_delete ('update', $values);
2048 =item Arguments: \%values
2050 =item Return Value: 1
2054 Fetches all objects and updates them one at a time via
2055 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
2056 triggers, while L</update> will not.
2061 my ($self, $values) = @_;
2062 $self->throw_exception('Values for update_all must be a hash')
2063 unless ref $values eq 'HASH';
2065 my $guard = $self->result_source->schema->txn_scope_guard;
2066 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
2075 =item Arguments: none
2077 =item Return Value: $underlying_storage_rv
2081 Deletes the rows matching this resultset in a single query. Note that this
2082 will not run any delete triggers, nor will it alter the
2083 L<in_storage|DBIx::Class::Row/in_storage> status of any result object instances
2084 derived from this resultset (this includes the contents of the
2085 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
2086 execute any on-delete triggers or cascades defined either by you or a
2087 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2089 The return value is a pass through of what the underlying storage backend
2090 returned, and may vary. See L<DBI/execute> for the most common case.
2096 $self->throw_exception('delete does not accept any arguments')
2099 return $self->_rs_update_delete ('delete');
2106 =item Arguments: none
2108 =item Return Value: 1
2112 Fetches all objects and deletes them one at a time via
2113 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2114 triggers, while L</delete> will not.
2120 $self->throw_exception('delete_all does not accept any arguments')
2123 my $guard = $self->result_source->schema->txn_scope_guard;
2124 $_->delete for $self->all;
2133 =item Arguments: [ \@column_list, \@row_values+ ] | [ \%col_data+ ]
2135 =item Return Value: L<\@result_objects|DBIx::Class::Manual::ResultClass> (scalar context) | L<@result_objects|DBIx::Class::Manual::ResultClass> (list context)
2139 Accepts either an arrayref of hashrefs or alternatively an arrayref of
2146 The context of this method call has an important effect on what is
2147 submitted to storage. In void context data is fed directly to fastpath
2148 insertion routines provided by the underlying storage (most often
2149 L<DBI/execute_for_fetch>), bypassing the L<new|DBIx::Class::Row/new> and
2150 L<insert|DBIx::Class::Row/insert> calls on the
2151 L<Result|DBIx::Class::Manual::ResultClass> class, including any
2152 augmentation of these methods provided by components. For example if you
2153 are using something like L<DBIx::Class::UUIDColumns> to create primary
2154 keys for you, you will find that your PKs are empty. In this case you
2155 will have to explicitly force scalar or list context in order to create
2160 In non-void (scalar or list) context, this method is simply a wrapper
2161 for L</create>. Depending on list or scalar context either a list of
2162 L<Result|DBIx::Class::Manual::ResultClass> objects or an arrayref
2163 containing these objects is returned.
2165 When supplying data in "arrayref of arrayrefs" invocation style, the
2166 first element should be a list of column names and each subsequent
2167 element should be a data value in the earlier specified column order.
2170 $schema->resultset("Artist")->populate([
2171 [ qw( artistid name ) ],
2172 [ 100, 'A Formally Unknown Singer' ],
2173 [ 101, 'A singer that jumped the shark two albums ago' ],
2174 [ 102, 'An actually cool singer' ],
2177 For the arrayref of hashrefs style each hashref should be a structure
2178 suitable for passing to L</create>. Multi-create is also permitted with
2181 $schema->resultset("Artist")->populate([
2182 { artistid => 4, name => 'Manufactured Crap', cds => [
2183 { title => 'My First CD', year => 2006 },
2184 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2187 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2188 { title => 'My parents sold me to a record company', year => 2005 },
2189 { title => 'Why Am I So Ugly?', year => 2006 },
2190 { title => 'I Got Surgery and am now Popular', year => 2007 }
2195 If you attempt a void-context multi-create as in the example above (each
2196 Artist also has the related list of CDs), and B<do not> supply the
2197 necessary autoinc foreign key information, this method will proxy to the
2198 less efficient L</create>, and then throw the Result objects away. In this
2199 case there are obviously no benefits to using this method over L</create>.
2206 # this is naive and just a quick check
2207 # the types will need to be checked more thoroughly when the
2208 # multi-source populate gets added
2210 ref $_[0] eq 'ARRAY'
2212 ( @{$_[0]} or return )
2214 ( ref $_[0][0] eq 'HASH' or ref $_[0][0] eq 'ARRAY' )
2217 ) or $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2219 # FIXME - no cref handling
2220 # At this point assume either hashes or arrays
2222 my $rsrc = $self->result_source;
2224 if(defined wantarray) {
2225 my (@results, $guard);
2227 if (ref $data->[0] eq 'ARRAY') {
2228 # column names only, nothing to do
2229 return if @$data == 1;
2231 $guard = $rsrc->schema->storage->txn_scope_guard
2235 { my $vals = $_; $self->new_result({ map { $data->[0][$_] => $vals->[$_] } 0..$#{$data->[0]} })->insert }
2236 @{$data}[1 .. $#$data]
2241 $guard = $rsrc->schema->storage->txn_scope_guard
2244 @results = map { $self->new_result($_)->insert } @$data;
2247 $guard->commit if $guard;
2248 return wantarray ? @results : \@results;
2251 # we have to deal with *possibly incomplete* related data
2252 # this means we have to walk the data structure twice
2253 # whether we want this or not
2254 # jnap, I hate you ;)
2255 my $rel_info = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2257 my ($colinfo, $colnames, $slices_with_rels);
2261 for my $i (0 .. $#$data) {
2263 my $current_slice_seen_rel_infos;
2265 ### Determine/Supplement collists
2266 ### BEWARE - This is a hot piece of code, a lot of weird idioms were used
2267 if( ref $data->[$i] eq 'ARRAY' ) {
2269 # positional(!) explicit column list
2271 # column names only, nothing to do
2272 return if @$data == 1;
2274 $colinfo->{$data->[0][$_]} = { pos => $_, name => $data->[0][$_] } and push @$colnames, $data->[0][$_]
2275 for 0 .. $#{$data->[0]};
2282 for (values %$colinfo) {
2283 if ($_->{is_rel} ||= (
2284 $rel_info->{$_->{name}}
2287 ref $data->[$i][$_->{pos}] eq 'ARRAY'
2289 ref $data->[$i][$_->{pos}] eq 'HASH'
2292 defined blessed $data->[$i][$_->{pos}]
2294 $data->[$i][$_->{pos}]->isa(
2295 $DBIx::Class::ResultSource::__expected_result_class_isa
2299 msg => 'Global $DBIx::Class::ResultSource::__expected_result_class_isa unexpectedly unset...'
2308 # moar sanity check... sigh
2309 for ( ref $data->[$i][$_->{pos}] eq 'ARRAY' ? @{$data->[$i][$_->{pos}]} : $data->[$i][$_->{pos}] ) {
2314 $DBIx::Class::ResultSource::__expected_result_class_isa
2318 msg => 'Global $DBIx::Class::ResultSource::__expected_result_class_isa unexpectedly unset...'
2322 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2323 return my $throwaway = $self->populate(@_);
2327 push @$current_slice_seen_rel_infos, $rel_info->{$_->{name}};
2332 if ($current_slice_seen_rel_infos) {
2333 push @$slices_with_rels, { map { $colnames->[$_] => $data->[$i][$_] } 0 .. $#$colnames };
2335 # this is needed further down to decide whether or not to fallback to create()
2336 $colinfo->{$colnames->[$_]}{seen_null} ||= ! defined $data->[$i][$_]
2337 for 0 .. $#$colnames;
2340 elsif( ref $data->[$i] eq 'HASH' ) {
2342 for ( sort keys %{$data->[$i]} ) {
2344 $colinfo->{$_} ||= do {
2346 $self->throw_exception("Column '$_' must be present in supplied explicit column list")
2347 if $data_start; # it will be 0 on AoH, 1 on AoA
2349 push @$colnames, $_;
2352 { pos => $#$colnames, name => $_ }
2355 if ($colinfo->{$_}{is_rel} ||= (
2359 ref $data->[$i]{$_} eq 'ARRAY'
2361 ref $data->[$i]{$_} eq 'HASH'
2364 defined blessed $data->[$i]{$_}
2366 $data->[$i]{$_}->isa(
2367 $DBIx::Class::ResultSource::__expected_result_class_isa
2371 msg => 'Global $DBIx::Class::ResultSource::__expected_result_class_isa unexpectedly unset...'
2380 # moar sanity check... sigh
2381 for ( ref $data->[$i]{$_} eq 'ARRAY' ? @{$data->[$i]{$_}} : $data->[$i]{$_} ) {
2386 $DBIx::Class::ResultSource::__expected_result_class_isa
2390 msg => 'Global $DBIx::Class::ResultSource::__expected_result_class_isa unexpectedly unset...'
2394 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2395 return my $throwaway = $self->populate(@_);
2399 push @$current_slice_seen_rel_infos, $rel_info->{$_};
2403 if ($current_slice_seen_rel_infos) {
2404 push @$slices_with_rels, $data->[$i];
2406 # this is needed further down to decide whether or not to fallback to create()
2407 $colinfo->{$_}{seen_null} ||= ! defined $data->[$i]{$_}
2408 for keys %{$data->[$i]};
2412 $self->throw_exception('Unexpected populate() data structure member type: ' . ref $data->[$i] );
2416 { $_->{attrs}{is_depends_on} }
2417 @{ $current_slice_seen_rel_infos || [] }
2419 carp_unique("Fast-path populate() of belongs_to relationship data is not possible - falling back to regular create()");
2420 return my $throwaway = $self->populate(@_);
2424 if( $slices_with_rels ) {
2426 # need to exclude the rel "columns"
2427 $colnames = [ grep { ! $colinfo->{$_}{is_rel} } @$colnames ];
2429 # extra sanity check - ensure the main source is in fact identifiable
2430 # the localizing of nullability is insane, but oh well... the use-case is legit
2431 my $ci = $rsrc->columns_info($colnames);
2433 $ci->{$_} = { %{$ci->{$_}}, is_nullable => 0 }
2434 for grep { ! $colinfo->{$_}{seen_null} } keys %$ci;
2436 unless( $rsrc->_identifying_column_set($ci) ) {
2437 carp_unique("Fast-path populate() of non-uniquely identifiable rows with related data is not possible - falling back to regular create()");
2438 return my $throwaway = $self->populate(@_);
2442 ### inherit the data locked in the conditions of the resultset
2443 my ($rs_data) = $self->_merge_with_rscond({});
2444 delete @{$rs_data}{@$colnames}; # passed-in stuff takes precedence
2446 # if anything left - decompose rs_data
2448 if (keys %$rs_data) {
2449 push @$rs_data_vals, $rs_data->{$_}
2450 for sort keys %$rs_data;
2455 $guard = $rsrc->schema->storage->txn_scope_guard
2456 if $slices_with_rels;
2458 ### main source data
2459 # FIXME - need to switch entirely to a coderef-based thing,
2460 # so that large sets aren't copied several times... I think
2461 $rsrc->schema->storage->_insert_bulk(
2463 [ @$colnames, sort keys %$rs_data ],
2465 ref $data->[$_] eq 'ARRAY'
2467 $slices_with_rels ? [ @{$data->[$_]}[0..$#$colnames], @{$rs_data_vals||[]} ] # the collist changed
2468 : $rs_data_vals ? [ @{$data->[$_]}, @$rs_data_vals ]
2471 : [ @{$data->[$_]}{@$colnames}, @{$rs_data_vals||[]} ]
2472 } $data_start .. $#$data ],
2475 ### do the children relationships
2476 if ( $slices_with_rels ) {
2477 my @rels = grep { $colinfo->{$_}{is_rel} } keys %$colinfo
2478 or die 'wtf... please report a bug with DBIC_TRACE=1 output (stacktrace)';
2480 for my $sl (@$slices_with_rels) {
2482 my ($main_proto, $main_proto_rs);
2483 for my $rel (@rels) {
2484 next unless defined $sl->{$rel};
2488 (map { $_ => $sl->{$_} } @$colnames),
2491 unless (defined $colinfo->{$rel}{rs}) {
2493 $colinfo->{$rel}{rs} = $rsrc->related_source($rel)->resultset;
2495 $colinfo->{$rel}{fk_map} = { reverse %{ $rsrc->_resolve_relationship_condition(
2497 self_alias => "\xFE", # irrelevant
2498 foreign_alias => "\xFF", # irrelevant
2499 )->{identity_map} || {} } };
2503 $colinfo->{$rel}{rs}->search({ map # only so that we inherit them values properly, no actual search
2506 ( $main_proto_rs ||= $rsrc->resultset->search($main_proto) )
2507 ->get_column( $colinfo->{$rel}{fk_map}{$_} )
2511 keys %{$colinfo->{$rel}{fk_map}}
2512 })->populate( ref $sl->{$rel} eq 'ARRAY' ? $sl->{$rel} : [ $sl->{$rel} ] );
2519 $guard->commit if $guard;
2526 =item Arguments: none
2528 =item Return Value: L<$pager|Data::Page>
2532 Returns a L<Data::Page> object for the current resultset. Only makes
2533 sense for queries with a C<page> attribute.
2535 To get the full count of entries for a paged resultset, call
2536 C<total_entries> on the L<Data::Page> object.
2543 return $self->{pager} if $self->{pager};
2545 my $attrs = $self->{attrs};
2546 if (!defined $attrs->{page}) {
2547 $self->throw_exception("Can't create pager for non-paged rs");
2549 elsif ($attrs->{page} <= 0) {
2550 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2552 $attrs->{rows} ||= 10;
2554 # throw away the paging flags and re-run the count (possibly
2555 # with a subselect) to get the real total count
2556 my $count_attrs = { %$attrs };
2557 delete @{$count_attrs}{qw/rows offset page pager/};
2559 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2561 require DBIx::Class::ResultSet::Pager;
2562 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2563 sub { $total_rs->count }, #lazy-get the total
2565 $self->{attrs}{page},
2573 =item Arguments: $page_number
2575 =item Return Value: L<$resultset|/search>
2579 Returns a resultset for the $page_number page of the resultset on which page
2580 is called, where each page contains a number of rows equal to the 'rows'
2581 attribute set on the resultset (10 by default).
2586 my ($self, $page) = @_;
2587 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2594 =item Arguments: \%col_data
2596 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2600 Creates a new result object in the resultset's result class and returns
2601 it. The row is not inserted into the database at this point, call
2602 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2603 will tell you whether the result object has been inserted or not.
2605 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2610 my ($self, $values) = @_;
2612 $self->throw_exception( "Result object instantiation requires a single hashref argument" )
2613 if @_ > 2 or ref $values ne 'HASH';
2615 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2617 my $new = $self->result_class->new({
2619 ( @$cols_from_relations
2620 ? (-cols_from_relations => $cols_from_relations)
2623 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2627 reftype($new) eq 'HASH'
2633 carp_unique (sprintf (
2634 "%s->new returned a blessed empty hashref - a strong indicator something is wrong with its inheritance chain",
2635 $self->result_class,
2642 # _merge_with_rscond
2644 # Takes a simple hash of K/V data and returns its copy merged with the
2645 # condition already present on the resultset. Additionally returns an
2646 # arrayref of value/condition names, which were inferred from related
2647 # objects (this is needed for in-memory related objects)
2648 sub _merge_with_rscond {
2649 my ($self, $data) = @_;
2651 my ($implied_data, @cols_from_relations);
2653 my $alias = $self->{attrs}{alias};
2655 if (! defined $self->{cond}) {
2656 # just massage $data below
2658 elsif ($self->{cond} eq UNRESOLVABLE_CONDITION) {
2659 $implied_data = $self->{attrs}{related_objects}; # nothing might have been inserted yet
2660 @cols_from_relations = keys %{ $implied_data || {} };
2663 my $eqs = extract_equality_conditions( $self->{cond}, 'consider_nulls' );
2664 $implied_data = { map {
2665 ( ($eqs->{$_}||'') eq UNRESOLVABLE_CONDITION ) ? () : ( $_ => $eqs->{$_} )
2671 { %{ $self->_remove_alias($_, $alias) } }
2672 # precedence must be given to passed values over values inherited from
2673 # the cond, so the order here is important.
2674 ( $implied_data||(), $data)
2676 \@cols_from_relations
2680 # _has_resolved_attr
2682 # determines if the resultset defines at least one
2683 # of the attributes supplied
2685 # used to determine if a subquery is necessary
2687 # supports some virtual attributes:
2689 # This will scan for any joins being present on the resultset.
2690 # It is not a mere key-search but a deep inspection of {from}
2693 sub _has_resolved_attr {
2694 my ($self, @attr_names) = @_;
2696 my $attrs = $self->_resolved_attrs;
2700 for my $n (@attr_names) {
2701 if (grep { $n eq $_ } (qw/-join/) ) {
2702 $extra_checks{$n}++;
2706 my $attr = $attrs->{$n};
2708 next if not defined $attr;
2710 if (ref $attr eq 'HASH') {
2711 return 1 if keys %$attr;
2713 elsif (ref $attr eq 'ARRAY') {
2721 # a resolved join is expressed as a multi-level from
2723 $extra_checks{-join}
2725 ref $attrs->{from} eq 'ARRAY'
2727 @{$attrs->{from}} > 1
2735 # Remove the specified alias from the specified query hash. A copy is made so
2736 # the original query is not modified.
2739 my ($self, $query, $alias) = @_;
2741 my %orig = %{ $query || {} };
2744 foreach my $key (keys %orig) {
2746 $unaliased{$key} = $orig{$key};
2749 $unaliased{$1} = $orig{$key}
2750 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2760 =item Arguments: none
2762 =item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
2766 Returns the SQL query and bind vars associated with the invocant.
2768 This is generally used as the RHS for a subquery.
2775 my $attrs = { %{ $self->_resolved_attrs } };
2777 my $aq = $self->result_source->schema->storage->_select_args_to_query (
2778 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
2788 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2790 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2794 my $artist = $schema->resultset('Artist')->find_or_new(
2795 { artist => 'fred' }, { key => 'artists' });
2797 $cd->cd_to_producer->find_or_new({ producer => $producer },
2798 { key => 'primary' });
2800 Find an existing record from this resultset using L</find>. if none exists,
2801 instantiate a new result object and return it. The object will not be saved
2802 into your storage until you call L<DBIx::Class::Row/insert> on it.
2804 You most likely want this method when looking for existing rows using a unique
2805 constraint that is not the primary key, or looking for related rows.
2807 If you want objects to be saved immediately, use L</find_or_create> instead.
2809 B<Note>: Make sure to read the documentation of L</find> and understand the
2810 significance of the C<key> attribute, as its lack may skew your search, and
2811 subsequently result in spurious new objects.
2813 B<Note>: Take care when using C<find_or_new> with a table having
2814 columns with default values that you intend to be automatically
2815 supplied by the database (e.g. an auto_increment primary key column).
2816 In normal usage, the value of such columns should NOT be included at
2817 all in the call to C<find_or_new>, even when set to C<undef>.
2823 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
2824 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2825 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2828 return $self->new_result($hash);
2835 =item Arguments: \%col_data
2837 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2841 Attempt to create a single new row or a row with multiple related rows
2842 in the table represented by the resultset (and related tables). This
2843 will not check for duplicate rows before inserting, use
2844 L</find_or_create> to do that.
2846 To create one row for this resultset, pass a hashref of key/value
2847 pairs representing the columns of the table and the values you wish to
2848 store. If the appropriate relationships are set up, foreign key fields
2849 can also be passed an object representing the foreign row, and the
2850 value will be set to its primary key.
2852 To create related objects, pass a hashref of related-object column values
2853 B<keyed on the relationship name>. If the relationship is of type C<multi>
2854 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2855 The process will correctly identify columns holding foreign keys, and will
2856 transparently populate them from the keys of the corresponding relation.
2857 This can be applied recursively, and will work correctly for a structure
2858 with an arbitrary depth and width, as long as the relationships actually
2859 exists and the correct column data has been supplied.
2861 Instead of hashrefs of plain related data (key/value pairs), you may
2862 also pass new or inserted objects. New objects (not inserted yet, see
2863 L</new_result>), will be inserted into their appropriate tables.
2865 Effectively a shortcut for C<< ->new_result(\%col_data)->insert >>.
2867 Example of creating a new row.
2869 $person_rs->create({
2870 name=>"Some Person",
2871 email=>"somebody@someplace.com"
2874 Example of creating a new row and also creating rows in a related C<has_many>
2875 or C<has_one> resultset. Note Arrayref.
2878 { artistid => 4, name => 'Manufactured Crap', cds => [
2879 { title => 'My First CD', year => 2006 },
2880 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2885 Example of creating a new row and also creating a row in a related
2886 C<belongs_to> resultset. Note Hashref.
2889 title=>"Music for Silly Walks",
2892 name=>"Silly Musician",
2900 When subclassing ResultSet never attempt to override this method. Since
2901 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2902 lot of the internals simply never call it, so your override will be
2903 bypassed more often than not. Override either L<DBIx::Class::Row/new>
2904 or L<DBIx::Class::Row/insert> depending on how early in the
2905 L</create> process you need to intervene. See also warning pertaining to
2912 sub create :DBIC_method_is_indirect_sugar {
2913 #my ($self, $col_data) = @_;
2914 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
2915 return shift->new_result(shift)->insert;
2918 =head2 find_or_create
2922 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2924 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2928 $cd->cd_to_producer->find_or_create({ producer => $producer },
2929 { key => 'primary' });
2931 Tries to find a record based on its primary key or unique constraints; if none
2932 is found, creates one and returns that instead.
2934 my $cd = $schema->resultset('CD')->find_or_create({
2936 artist => 'Massive Attack',
2937 title => 'Mezzanine',
2941 Also takes an optional C<key> attribute, to search by a specific key or unique
2942 constraint. For example:
2944 my $cd = $schema->resultset('CD')->find_or_create(
2946 artist => 'Massive Attack',
2947 title => 'Mezzanine',
2949 { key => 'cd_artist_title' }
2952 B<Note>: Make sure to read the documentation of L</find> and understand the
2953 significance of the C<key> attribute, as its lack may skew your search, and
2954 subsequently result in spurious row creation.
2956 B<Note>: Because find_or_create() reads from the database and then
2957 possibly inserts based on the result, this method is subject to a race
2958 condition. Another process could create a record in the table after
2959 the find has completed and before the create has started. To avoid
2960 this problem, use find_or_create() inside a transaction.
2962 B<Note>: Take care when using C<find_or_create> with a table having
2963 columns with default values that you intend to be automatically
2964 supplied by the database (e.g. an auto_increment primary key column).
2965 In normal usage, the value of such columns should NOT be included at
2966 all in the call to C<find_or_create>, even when set to C<undef>.
2968 See also L</find> and L</update_or_create>. For information on how to declare
2969 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2971 If you need to know if an existing row was found or a new one created use
2972 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2973 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2976 my $cd = $schema->resultset('CD')->find_or_new({
2978 artist => 'Massive Attack',
2979 title => 'Mezzanine',
2983 if( !$cd->in_storage ) {
2990 sub find_or_create {
2992 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
2993 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2994 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2997 return $self->new_result($hash)->insert;
3000 =head2 update_or_create
3004 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
3006 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
3010 $resultset->update_or_create({ col => $val, ... });
3012 Like L</find_or_create>, but if a row is found it is immediately updated via
3013 C<< $found_row->update (\%col_data) >>.
3016 Takes an optional C<key> attribute to search on a specific unique constraint.
3019 # In your application
3020 my $cd = $schema->resultset('CD')->update_or_create(
3022 artist => 'Massive Attack',
3023 title => 'Mezzanine',
3026 { key => 'cd_artist_title' }
3029 $cd->cd_to_producer->update_or_create({
3030 producer => $producer,
3036 B<Note>: Make sure to read the documentation of L</find> and understand the
3037 significance of the C<key> attribute, as its lack may skew your search, and
3038 subsequently result in spurious row creation.
3040 B<Note>: Take care when using C<update_or_create> with a table having
3041 columns with default values that you intend to be automatically
3042 supplied by the database (e.g. an auto_increment primary key column).
3043 In normal usage, the value of such columns should NOT be included at
3044 all in the call to C<update_or_create>, even when set to C<undef>.
3046 See also L</find> and L</find_or_create>. For information on how to declare
3047 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
3049 If you need to know if an existing row was updated or a new one created use
3050 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
3051 to call L<DBIx::Class::Row/insert> to save the newly created row to the
3056 sub update_or_create {
3058 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
3059 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3061 my $row = $self->find($cond, $attrs);
3063 $row->update($cond);
3067 return $self->new_result($cond)->insert;
3070 =head2 update_or_new
3074 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
3076 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
3080 $resultset->update_or_new({ col => $val, ... });
3082 Like L</find_or_new> but if a row is found it is immediately updated via
3083 C<< $found_row->update (\%col_data) >>.
3087 # In your application
3088 my $cd = $schema->resultset('CD')->update_or_new(
3090 artist => 'Massive Attack',
3091 title => 'Mezzanine',
3094 { key => 'cd_artist_title' }
3097 if ($cd->in_storage) {
3098 # the cd was updated
3101 # the cd is not yet in the database, let's insert it
3105 B<Note>: Make sure to read the documentation of L</find> and understand the
3106 significance of the C<key> attribute, as its lack may skew your search, and
3107 subsequently result in spurious new objects.
3109 B<Note>: Take care when using C<update_or_new> with a table having
3110 columns with default values that you intend to be automatically
3111 supplied by the database (e.g. an auto_increment primary key column).
3112 In normal usage, the value of such columns should NOT be included at
3113 all in the call to C<update_or_new>, even when set to C<undef>.
3115 See also L</find>, L</find_or_create> and L</find_or_new>.
3121 my $attrs = ( @_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {} );
3122 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3124 my $row = $self->find( $cond, $attrs );
3125 if ( defined $row ) {
3126 $row->update($cond);
3130 return $self->new_result($cond);
3137 =item Arguments: none
3139 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass> | undef
3143 Gets the contents of the cache for the resultset, if the cache is set.
3145 The cache is populated either by using the L</prefetch> attribute to
3146 L</search> or by calling L</set_cache>.
3158 =item Arguments: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3160 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3164 Sets the contents of the cache for the resultset. Expects an arrayref
3165 of objects of the same class as those produced by the resultset. Note that
3166 if the cache is set, the resultset will return the cached objects rather
3167 than re-querying the database even if the cache attr is not set.
3169 The contents of the cache can also be populated by using the
3170 L</prefetch> attribute to L</search>.
3175 my ( $self, $data ) = @_;
3176 $self->throw_exception("set_cache requires an arrayref")
3177 if defined($data) && (ref $data ne 'ARRAY');
3178 $self->{all_cache} = $data;
3185 =item Arguments: none
3187 =item Return Value: undef
3191 Clears the cache for the resultset.
3196 shift->set_cache(undef);
3203 =item Arguments: none
3205 =item Return Value: true, if the resultset has been paginated
3213 return !!$self->{attrs}{page};
3220 =item Arguments: none
3222 =item Return Value: true, if the resultset has been ordered with C<order_by>.
3230 return scalar $self->result_source->schema->storage->_extract_order_criteria($self->{attrs}{order_by});
3233 =head2 related_resultset
3237 =item Arguments: $rel_name
3239 =item Return Value: L<$resultset|/search>
3243 Returns a related resultset for the supplied relationship name.
3245 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
3249 sub related_resultset {
3250 $_[0]->throw_exception(
3251 'Extra arguments to $rs->related_resultset() were always quietly '
3252 . 'discarded without consideration, you need to switch to '
3253 . '...->related_resultset( $relname )->search_rs( $search, $args ) instead.'
3256 return $_[0]->{related_resultsets}{$_[1]}
3257 if defined $_[0]->{related_resultsets}{$_[1]};
3259 my ($self, $rel) = @_;
3261 return $self->{related_resultsets}{$rel} = do {
3262 my $rsrc = $self->result_source;
3263 my $rel_info = $rsrc->relationship_info($rel);
3265 $self->throw_exception(
3266 "search_related: result source '" . $rsrc->source_name .
3267 "' has no such relationship $rel")
3270 my $attrs = $self->_chain_relationship($rel);
3272 my $storage = $rsrc->schema->storage;
3274 # Previously this atribute was deleted (instead of being set as it is now)
3275 # Doing so seems to be harmless in all available test permutations
3276 # See also 01d59a6a6 and mst's comment below
3278 $attrs->{alias} = $storage->relname_to_table_alias(
3280 $attrs->{seen_join}{$rel}
3283 # since this is search_related, and we already slid the select window inwards
3284 # (the select/as attrs were deleted in the beginning), we need to flip all
3285 # left joins to inner, so we get the expected results
3287 # The DBIC relationship chaining implementation is pretty simple - every
3288 # new related_relationship is pushed onto the {from} stack, and the {select}
3289 # window simply slides further in. This means that when we count somewhere
3290 # in the middle, we got to make sure that everything in the join chain is an
3291 # actual inner join, otherwise the count will come back with unpredictable
3292 # results (a resultset may be generated with _some_ rows regardless of if
3293 # the relation which the $rs currently selects has rows or not). E.g.
3294 # $artist_rs->cds->count - normally generates:
3295 # SELECT COUNT( * ) FROM artist me LEFT JOIN cd cds ON cds.artist = me.artistid
3296 # which actually returns the number of artists * (number of cds || 1)
3298 # So what we do here is crawl {from}, determine if the current alias is at
3299 # the top of the stack, and if not - make sure the chain is inner-joined down
3302 my $switch_branch = $storage->_find_join_path_to_node(
3307 if ( @{ $switch_branch || [] } ) {
3309 # So it looks like we will have to switch some stuff around.
3310 # local() is useless here as we will be leaving the scope
3311 # anyway, and deep cloning is just too fucking expensive
3312 # So replace the first hashref in the node arrayref manually
3313 my @new_from = $attrs->{from}[0];
3314 my $sw_idx = { map { (values %$_), 1 } @$switch_branch }; #there's one k/v per join-path
3316 for my $j ( @{$attrs->{from}}[ 1 .. $#{$attrs->{from}} ] ) {
3317 my $jalias = $j->[0]{-alias};
3319 if ($sw_idx->{$jalias}) {
3320 my %attrs = %{$j->[0]};
3321 delete $attrs{-join_type};
3332 $attrs->{from} = \@new_from;
3336 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3337 delete $attrs->{result_class};
3341 # The reason we do this now instead of passing the alias to the
3342 # search_rs below is that if you wrap/overload resultset on the
3343 # source you need to know what alias it's -going- to have for things
3344 # to work sanely (e.g. RestrictWithObject wants to be able to add
3345 # extra query restrictions, and these may need to be $alias.)
3346 # -- mst ~ 2007 (01d59a6a6)
3348 # FIXME - this seems to be no longer neccessary (perhaps due to the
3349 # advances in relcond resolution. Testing DBIC::S::RWO and its only
3350 # dependent (as of Jun 2015 ) does not yield any difference with or
3351 # without this line. Nevertheless keep it as is for now, to minimize
3352 # churn, there is enough potential for breakage in 0.0829xx as it is
3353 # -- ribasushi Jun 2015
3355 my $rel_source = $rsrc->related_source($rel);
3356 local $rel_source->resultset_attributes->{alias} = $attrs->{alias};
3358 $rel_source->resultset->search_rs( undef, $attrs );
3361 if (my $cache = $self->get_cache) {
3362 my @related_cache = map
3363 { $_->related_resultset($rel)->get_cache || () }
3367 $new->set_cache([ map @$_, @related_cache ]) if @related_cache == @$cache;
3374 =head2 current_source_alias
3378 =item Arguments: none
3380 =item Return Value: $source_alias
3384 Returns the current table alias for the result source this resultset is built
3385 on, that will be used in the SQL query. Usually it is C<me>.
3387 Currently the source alias that refers to the result set returned by a
3388 L</search>/L</find> family method depends on how you got to the resultset: it's
3389 C<me> by default, but eg. L</search_related> aliases it to the related result
3390 source name (and keeps C<me> referring to the original result set). The long
3391 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3392 (and make this method unnecessary).
3394 Thus it's currently necessary to use this method in predefined queries (see
3395 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3396 source alias of the current result set:
3398 # in a result set class
3400 my ($self, $user) = @_;
3402 my $me = $self->current_source_alias;
3404 return $self->search({
3405 "$me.modified" => $user->id,
3409 The alias of L<newly created resultsets|/search> can be altered by the
3410 L<alias attribute|/alias>.
3414 sub current_source_alias {
3415 return (shift->{attrs} || {})->{alias} || 'me';
3418 =head2 as_subselect_rs
3422 =item Arguments: none
3424 =item Return Value: L<$resultset|/search>
3428 Act as a barrier to SQL symbols. The resultset provided will be made into a
3429 "virtual view" by including it as a subquery within the from clause. From this
3430 point on, any joined tables are inaccessible to ->search on the resultset (as if
3431 it were simply where-filtered without joins). For example:
3433 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3435 # 'x' now pollutes the query namespace
3437 # So the following works as expected
3438 my $ok_rs = $rs->search({'x.other' => 1});
3440 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3441 # def) we look for one row with contradictory terms and join in another table
3442 # (aliased 'x_2') which we never use
3443 my $broken_rs = $rs->search({'x.name' => 'def'});
3445 my $rs2 = $rs->as_subselect_rs;
3447 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3448 my $not_joined_rs = $rs2->search({'x.other' => 1});
3450 # works as expected: finds a 'table' row related to two x rows (abc and def)
3451 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3453 Another example of when one might use this would be to select a subset of
3454 columns in a group by clause:
3456 my $rs = $schema->resultset('Bar')->search(undef, {
3457 group_by => [qw{ id foo_id baz_id }],
3458 })->as_subselect_rs->search(undef, {
3459 columns => [qw{ id foo_id }]
3462 In the above example normally columns would have to be equal to the group by,
3463 but because we isolated the group by into a subselect the above works.
3467 sub as_subselect_rs {
3470 my $attrs = $self->_resolved_attrs;
3472 my $fresh_rs = (ref $self)->new (
3473 $self->result_source
3476 # these pieces will be locked in the subquery
3477 delete $fresh_rs->{cond};
3478 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3480 return $fresh_rs->search( {}, {
3482 $attrs->{alias} => $self->as_query,
3483 -alias => $attrs->{alias},
3484 -rsrc => $self->result_source,
3486 alias => $attrs->{alias},
3490 # This code is called by search_related, and makes sure there
3491 # is clear separation between the joins before, during, and
3492 # after the relationship. This information is needed later
3493 # in order to properly resolve prefetch aliases (any alias
3494 # with a relation_chain_depth less than the depth of the
3495 # current prefetch is not considered)
3497 # The increments happen twice per join. An even number means a
3498 # relationship specified via a search_related, whereas an odd
3499 # number indicates a join/prefetch added via attributes
3501 # Also this code will wrap the current resultset (the one we
3502 # chain to) in a subselect IFF it contains limiting attributes
3503 sub _chain_relationship {
3504 my ($self, $rel) = @_;
3505 my $source = $self->result_source;
3506 my $attrs = { %{$self->{attrs}||{}} };
3508 # we need to take the prefetch the attrs into account before we
3509 # ->_resolve_join as otherwise they get lost - captainL
3510 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3512 delete @{$attrs}{qw/join prefetch collapse group_by distinct _grouped_by_distinct select as columns +select +as +columns/};
3514 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3517 my @force_subq_attrs = qw/offset rows group_by having/;
3520 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3522 $self->_has_resolved_attr (@force_subq_attrs)
3524 # Nuke the prefetch (if any) before the new $rs attrs
3525 # are resolved (prefetch is useless - we are wrapping
3526 # a subquery anyway).
3527 my $rs_copy = $self->search;
3528 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3529 $rs_copy->{attrs}{join},
3530 delete $rs_copy->{attrs}{prefetch},
3535 -alias => $attrs->{alias},
3536 $attrs->{alias} => $rs_copy->as_query,
3538 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3539 $seen->{-relation_chain_depth} = 0;
3541 elsif ($attrs->{from}) { #shallow copy suffices
3542 $from = [ @{$attrs->{from}} ];
3547 -alias => $attrs->{alias},
3548 $attrs->{alias} => $source->from,
3552 my $jpath = ($seen->{-relation_chain_depth})
3553 ? $from->[-1][0]{-join_path}
3556 my @requested_joins = $source->_resolve_join(
3563 push @$from, @requested_joins;
3565 $seen->{-relation_chain_depth}++;
3567 # if $self already had a join/prefetch specified on it, the requested
3568 # $rel might very well be already included. What we do in this case
3569 # is effectively a no-op (except that we bump up the chain_depth on
3570 # the join in question so we could tell it *is* the search_related)
3573 # we consider the last one thus reverse
3574 for my $j (reverse @requested_joins) {
3575 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3576 if ($rel eq $last_j) {
3577 $j->[0]{-relation_chain_depth}++;
3583 unless ($already_joined) {
3584 push @$from, $source->_resolve_join(
3592 $seen->{-relation_chain_depth}++;
3594 return {%$attrs, from => $from, seen_join => $seen};
3597 sub _resolved_attrs {
3599 return $self->{_attrs} if $self->{_attrs};
3601 my $attrs = { %{ $self->{attrs} || {} } };
3602 my $source = $attrs->{result_source} = $self->result_source;
3603 my $alias = $attrs->{alias};
3605 $self->throw_exception("Specifying distinct => 1 in conjunction with collapse => 1 is unsupported")
3606 if $attrs->{collapse} and $attrs->{distinct};
3609 # Sanity check the paging attributes
3610 # SQLMaker does it too, but in case of a software_limit we'll never get there
3611 if (defined $attrs->{offset}) {
3612 $self->throw_exception('A supplied offset attribute must be a non-negative integer')
3613 if ( $attrs->{offset} =~ /[^0-9]/ or $attrs->{offset} < 0 );
3615 if (defined $attrs->{rows}) {
3616 $self->throw_exception("The rows attribute must be a positive integer if present")
3617 if ( $attrs->{rows} =~ /[^0-9]/ or $attrs->{rows} <= 0 );
3620 # normalize where condition
3621 $attrs->{where} = normalize_sqla_condition( $attrs->{where} )
3624 # default selection list
3625 $attrs->{columns} = [ $source->columns ]
3626 unless grep { exists $attrs->{$_} } qw/columns cols select as/;
3628 # merge selectors together
3629 for (qw/columns select as/) {
3630 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3631 if $attrs->{$_} or $attrs->{"+$_"};
3634 # disassemble columns
3636 if (my $cols = delete $attrs->{columns}) {
3637 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3638 if (ref $c eq 'HASH') {
3639 for my $as (sort keys %$c) {
3640 push @sel, $c->{$as};
3651 # when trying to weed off duplicates later do not go past this point -
3652 # everything added from here on is unbalanced "anyone's guess" stuff
3653 my $dedup_stop_idx = $#as;
3655 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3657 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3658 if $attrs->{select};
3660 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3661 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3663 # disqualify all $alias.col as-bits (inflate-map mandated)
3664 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3666 # de-duplicate the result (remove *identical* select/as pairs)
3667 # and also die on duplicate {as} pointing to different {select}s
3668 # not using a c-style for as the condition is prone to shrinkage
3671 while ($i <= $dedup_stop_idx) {
3672 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3677 elsif ($seen->{$as[$i]}++) {
3678 $self->throw_exception(
3679 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3687 $attrs->{select} = \@sel;
3688 $attrs->{as} = \@as;
3690 $attrs->{from} ||= [{
3692 -alias => $self->{attrs}{alias},
3693 $self->{attrs}{alias} => $source->from,
3696 if ( $attrs->{join} || $attrs->{prefetch} ) {
3698 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3699 if ref $attrs->{from} ne 'ARRAY';
3701 my $join = (delete $attrs->{join}) || {};
3703 if ( defined $attrs->{prefetch} ) {
3704 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3707 $attrs->{from} = # have to copy here to avoid corrupting the original
3709 @{ $attrs->{from} },
3710 $source->_resolve_join(
3713 { %{ $attrs->{seen_join} || {} } },
3714 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3715 ? $attrs->{from}[-1][0]{-join_path}
3723 for my $attr (qw(order_by group_by)) {
3725 if ( defined $attrs->{$attr} ) {
3727 ref( $attrs->{$attr} ) eq 'ARRAY'
3728 ? [ @{ $attrs->{$attr} } ]
3729 : [ $attrs->{$attr} || () ]
3732 delete $attrs->{$attr} unless @{$attrs->{$attr}};
3737 # set collapse default based on presence of prefetch
3740 defined $attrs->{prefetch}
3742 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3744 $self->throw_exception("Specifying prefetch in conjunction with an explicit collapse => 0 is unsupported")
3745 if defined $attrs->{collapse} and ! $attrs->{collapse};
3747 $attrs->{collapse} = 1;
3751 # run through the resulting joinstructure (starting from our current slot)
3752 # and unset collapse if proven unnecessary
3754 # also while we are at it find out if the current root source has
3755 # been premultiplied by previous related_source chaining
3757 # this allows to predict whether a root object with all other relation
3758 # data set to NULL is in fact unique
3759 if ($attrs->{collapse}) {
3761 if (ref $attrs->{from} eq 'ARRAY') {
3763 if (@{$attrs->{from}} == 1) {
3764 # no joins - no collapse
3765 $attrs->{collapse} = 0;
3768 # find where our table-spec starts
3769 my @fromlist = @{$attrs->{from}};
3771 my $t = shift @fromlist;
3774 # me vs join from-spec distinction - a ref means non-root
3775 if (ref $t eq 'ARRAY') {
3777 $is_multi ||= ! $t->{-is_single};
3779 last if ($t->{-alias} && $t->{-alias} eq $alias);
3780 $attrs->{_main_source_premultiplied} ||= $is_multi;
3783 # no non-singles remaining, nor any premultiplication - nothing to collapse
3785 ! $attrs->{_main_source_premultiplied}
3787 ! grep { ! $_->[0]{-is_single} } @fromlist
3789 $attrs->{collapse} = 0;
3795 # if we can not analyze the from - err on the side of safety
3796 $attrs->{_main_source_premultiplied} = 1;
3801 # generate the distinct induced group_by before injecting the prefetched select/as parts
3802 if (delete $attrs->{distinct}) {
3803 if ($attrs->{group_by}) {
3804 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3807 $attrs->{_grouped_by_distinct} = 1;
3808 # distinct affects only the main selection part, not what prefetch may add below
3809 ($attrs->{group_by}, my $new_order) = $source->schema->storage->_group_over_selection($attrs);
3811 # FIXME possibly ignore a rewritten order_by (may turn out to be an issue)
3812 # The thinking is: if we are collapsing the subquerying prefetch engine will
3813 # rip stuff apart for us anyway, and we do not want to have a potentially
3814 # function-converted external order_by
3815 # ( there is an explicit if ( collapse && _grouped_by_distinct ) check in DBIHacks )
3816 $attrs->{order_by} = $new_order unless $attrs->{collapse};
3821 # generate selections based on the prefetch helper
3824 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3825 if $attrs->{_dark_selector};
3827 # this is a separate structure (we don't look in {from} directly)
3828 # as the resolver needs to shift things off the lists to work
3829 # properly (identical-prefetches on different branches)
3830 my $joined_node_aliases_map = {};
3831 if (ref $attrs->{from} eq 'ARRAY') {
3833 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3835 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3836 next unless $j->[0]{-alias};
3837 next unless $j->[0]{-join_path};
3838 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3840 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3842 my $p = $joined_node_aliases_map;
3843 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3844 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3848 ( push @{$attrs->{select}}, $_->[0] ) and ( push @{$attrs->{as}}, $_->[1] )
3849 for $source->_resolve_selection_from_prefetch( $prefetch, $joined_node_aliases_map );
3853 $attrs->{_simple_passthrough_construction} = !(
3856 grep { $_ =~ /\./ } @{$attrs->{as}}
3860 # if both page and offset are specified, produce a combined offset
3861 # even though it doesn't make much sense, this is what pre 081xx has
3863 if (my $page = delete $attrs->{page}) {
3865 ($attrs->{rows} * ($page - 1))
3867 ($attrs->{offset} || 0)
3871 return $self->{_attrs} = $attrs;
3875 my ($self, $attr) = @_;
3877 if (ref $attr eq 'HASH') {
3878 return $self->_rollout_hash($attr);
3879 } elsif (ref $attr eq 'ARRAY') {
3880 return $self->_rollout_array($attr);
3886 sub _rollout_array {
3887 my ($self, $attr) = @_;
3890 foreach my $element (@{$attr}) {
3891 if (ref $element eq 'HASH') {
3892 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3893 } elsif (ref $element eq 'ARRAY') {
3894 # XXX - should probably recurse here
3895 push( @rolled_array, @{$self->_rollout_array($element)} );
3897 push( @rolled_array, $element );
3900 return \@rolled_array;
3904 my ($self, $attr) = @_;
3907 foreach my $key (keys %{$attr}) {
3908 push( @rolled_array, { $key => $attr->{$key} } );
3910 return \@rolled_array;
3913 sub _calculate_score {
3914 my ($self, $a, $b) = @_;
3916 if (defined $a xor defined $b) {
3919 elsif (not defined $a) {
3923 if (ref $b eq 'HASH') {
3924 my ($b_key) = keys %{$b};
3925 $b_key = '' if ! defined $b_key;
3926 if (ref $a eq 'HASH') {
3927 my ($a_key) = keys %{$a};
3928 $a_key = '' if ! defined $a_key;
3929 if ($a_key eq $b_key) {
3930 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3935 return ($a eq $b_key) ? 1 : 0;
3938 if (ref $a eq 'HASH') {
3939 my ($a_key) = keys %{$a};
3940 return ($b eq $a_key) ? 1 : 0;
3942 return ($b eq $a) ? 1 : 0;
3947 sub _merge_joinpref_attr {
3948 my ($self, $orig, $import) = @_;
3950 return $import unless defined($orig);
3951 return $orig unless defined($import);
3953 $orig = $self->_rollout_attr($orig);
3954 $import = $self->_rollout_attr($import);
3957 foreach my $import_element ( @{$import} ) {
3958 # find best candidate from $orig to merge $b_element into
3959 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3960 foreach my $orig_element ( @{$orig} ) {
3961 my $score = $self->_calculate_score( $orig_element, $import_element );
3962 if ($score > $best_candidate->{score}) {
3963 $best_candidate->{position} = $position;
3964 $best_candidate->{score} = $score;
3968 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3969 $import_key = '' if not defined $import_key;
3971 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3972 push( @{$orig}, $import_element );
3974 my $orig_best = $orig->[$best_candidate->{position}];
3975 # merge orig_best and b_element together and replace original with merged
3976 if (ref $orig_best ne 'HASH') {
3977 $orig->[$best_candidate->{position}] = $import_element;
3978 } elsif (ref $import_element eq 'HASH') {
3979 my ($key) = keys %{$orig_best};
3980 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3983 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3986 return @$orig ? $orig : ();
3994 require Hash::Merge;
3995 my $hm = Hash::Merge->new;
3997 $hm->specify_behavior({
4000 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
4002 if ($defl xor $defr) {
4003 return [ $defl ? $_[0] : $_[1] ];
4008 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
4012 return [$_[0], $_[1]];
4016 return $_[1] if !defined $_[0];
4017 return $_[1] if __HM_DEDUP and grep { $_ eq $_[0] } @{$_[1]};
4018 return [$_[0], @{$_[1]}]
4021 return [] if !defined $_[0] and !keys %{$_[1]};
4022 return [ $_[1] ] if !defined $_[0];
4023 return [ $_[0] ] if !keys %{$_[1]};
4024 return [$_[0], $_[1]]
4029 return $_[0] if !defined $_[1];
4030 return $_[0] if __HM_DEDUP and grep { $_ eq $_[1] } @{$_[0]};
4031 return [@{$_[0]}, $_[1]]
4034 my @ret = @{$_[0]} or return $_[1];
4035 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
4036 my %idx = map { $_ => 1 } @ret;
4037 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
4041 return [ $_[1] ] if ! @{$_[0]};
4042 return $_[0] if !keys %{$_[1]};
4043 return $_[0] if __HM_DEDUP and grep { $_ eq $_[1] } @{$_[0]};
4044 return [ @{$_[0]}, $_[1] ];
4049 return [] if !keys %{$_[0]} and !defined $_[1];
4050 return [ $_[0] ] if !defined $_[1];
4051 return [ $_[1] ] if !keys %{$_[0]};
4052 return [$_[0], $_[1]]
4055 return [] if !keys %{$_[0]} and !@{$_[1]};
4056 return [ $_[0] ] if !@{$_[1]};
4057 return $_[1] if !keys %{$_[0]};
4058 return $_[1] if __HM_DEDUP and grep { $_ eq $_[0] } @{$_[1]};
4059 return [ $_[0], @{$_[1]} ];
4062 return [] if !keys %{$_[0]} and !keys %{$_[1]};
4063 return [ $_[0] ] if !keys %{$_[1]};
4064 return [ $_[1] ] if !keys %{$_[0]};
4065 return [ $_[0] ] if $_[0] eq $_[1];
4066 return [ $_[0], $_[1] ];
4069 } => 'DBIC_RS_ATTR_MERGER');
4073 return $hm->merge ($_[1], $_[2]);
4077 sub STORABLE_freeze {
4078 my ($self, $cloning) = @_;
4079 my $to_serialize = { %$self };
4081 # A cursor in progress can't be serialized (and would make little sense anyway)
4082 # the parser can be regenerated (and can't be serialized)
4083 delete @{$to_serialize}{qw/cursor _row_parser _result_inflator/};
4085 # nor is it sensical to store a not-yet-fired-count pager
4086 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
4087 delete $to_serialize->{pager};
4090 Storable::nfreeze($to_serialize);
4093 # need this hook for symmetry
4095 my ($self, $cloning, $serialized) = @_;
4097 %$self = %{ Storable::thaw($serialized) };
4103 =head2 throw_exception
4105 See L<DBIx::Class::Schema/throw_exception> for details.
4109 sub throw_exception {
4112 if (ref $self and my $rsrc = $self->result_source) {
4113 $rsrc->throw_exception(@_)
4116 DBIx::Class::Exception->throw(@_);
4124 # XXX: FIXME: Attributes docs need clearing up
4128 Attributes are used to refine a ResultSet in various ways when
4129 searching for data. They can be passed to any method which takes an
4130 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
4133 Default attributes can be set on the result class using
4134 L<DBIx::Class::ResultSource/resultset_attributes>. (Please read
4135 the CAVEATS on that feature before using it!)
4137 These are in no particular order:
4143 =item Value: ( $order_by | \@order_by | \%order_by )
4147 Which column(s) to order the results by.
4149 [The full list of suitable values is documented in
4150 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
4153 If a single column name, or an arrayref of names is supplied, the
4154 argument is passed through directly to SQL. The hashref syntax allows
4155 for connection-agnostic specification of ordering direction:
4157 For descending order:
4159 order_by => { -desc => [qw/col1 col2 col3/] }
4161 For explicit ascending order:
4163 order_by => { -asc => 'col' }
4165 The old scalarref syntax (i.e. order_by => \'year DESC') is still
4166 supported, although you are strongly encouraged to use the hashref
4167 syntax as outlined above.
4173 =item Value: \@columns | \%columns | $column
4177 Shortcut to request a particular set of columns to be retrieved. Each
4178 column spec may be a string (a table column name), or a hash (in which
4179 case the key is the C<as> value, and the value is used as the C<select>
4180 expression). Adds the L</current_source_alias> onto the start of any column without a C<.> in
4181 it and sets C<select> from that, then auto-populates C<as> from
4182 C<select> as normal. (You may also use the C<cols> attribute, as in
4183 earlier versions of DBIC, but this is deprecated)
4185 Essentially C<columns> does the same as L</select> and L</as>.
4187 columns => [ 'some_column', { dbic_slot => 'another_column' } ]
4191 select => [qw(some_column another_column)],
4192 as => [qw(some_column dbic_slot)]
4194 If you want to individually retrieve related columns (in essence perform
4195 manual L</prefetch>) you have to make sure to specify the correct inflation slot
4196 chain such that it matches existing relationships:
4198 my $rs = $schema->resultset('Artist')->search({}, {
4199 # required to tell DBIC to collapse has_many relationships
4201 join => { cds => 'tracks' },
4203 'cds.cdid' => 'cds.cdid',
4204 'cds.tracks.title' => 'tracks.title',
4208 Like elsewhere, literal SQL or literal values can be included by using a
4209 scalar reference or a literal bind value, and these values will be available
4210 in the result with C<get_column> (see also
4211 L<SQL::Abstract/Literal SQL and value type operators>):
4213 # equivalent SQL: SELECT 1, 'a string', IF(my_column,?,?) ...
4214 # bind values: $true_value, $false_value
4218 bar => \q{'a string'},
4219 baz => \[ 'IF(my_column,?,?)', $true_value, $false_value ],
4225 B<NOTE:> You B<MUST> explicitly quote C<'+columns'> when using this attribute.
4226 Not doing so causes Perl to incorrectly interpret C<+columns> as a bareword
4227 with a unary plus operator before it, which is the same as simply C<columns>.
4231 =item Value: \@extra_columns
4235 Indicates additional columns to be selected from storage. Works the same as
4236 L</columns> but adds columns to the current selection. (You may also use the
4237 C<include_columns> attribute, as in earlier versions of DBIC, but this is
4240 $schema->resultset('CD')->search(undef, {
4241 '+columns' => ['artist.name'],
4245 would return all CDs and include a 'name' column to the information
4246 passed to object inflation. Note that the 'artist' is the name of the
4247 column (or relationship) accessor, and 'name' is the name of the column
4248 accessor in the related table.
4254 =item Value: \@select_columns
4258 Indicates which columns should be selected from the storage. You can use
4259 column names, or in the case of RDBMS back ends, function or stored procedure
4262 $rs = $schema->resultset('Employee')->search(undef, {
4265 { count => 'employeeid' },
4266 { max => { length => 'name' }, -as => 'longest_name' }
4271 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
4273 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
4274 use L</select>, to instruct DBIx::Class how to store the result of the column.
4276 Also note that the L</as> attribute has B<nothing to do> with the SQL-side
4277 C<AS> identifier aliasing. You B<can> alias a function (so you can use it e.g.
4278 in an C<ORDER BY> clause), however this is done via the C<-as> B<select
4279 function attribute> supplied as shown in the example above.
4283 B<NOTE:> You B<MUST> explicitly quote C<'+select'> when using this attribute.
4284 Not doing so causes Perl to incorrectly interpret C<+select> as a bareword
4285 with a unary plus operator before it, which is the same as simply C<select>.
4289 =item Value: \@extra_select_columns
4293 Indicates additional columns to be selected from storage. Works the same as
4294 L</select> but adds columns to the current selection, instead of specifying
4295 a new explicit list.
4301 =item Value: \@inflation_names
4305 Indicates DBIC-side names for object inflation. That is L</as> indicates the
4306 slot name in which the column value will be stored within the
4307 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
4308 identifier by the C<get_column> method (or via the object accessor B<if one
4309 with the same name already exists>) as shown below.
4311 The L</as> attribute has B<nothing to do> with the SQL-side identifier
4312 aliasing C<AS>. See L</select> for details.
4314 $rs = $schema->resultset('Employee')->search(undef, {
4317 { count => 'employeeid' },
4318 { max => { length => 'name' }, -as => 'longest_name' }
4327 If the object against which the search is performed already has an accessor
4328 matching a column name specified in C<as>, the value can be retrieved using
4329 the accessor as normal:
4331 my $name = $employee->name();
4333 If on the other hand an accessor does not exist in the object, you need to
4334 use C<get_column> instead:
4336 my $employee_count = $employee->get_column('employee_count');
4338 You can create your own accessors if required - see
4339 L<DBIx::Class::Manual::Cookbook> for details.
4343 B<NOTE:> You B<MUST> explicitly quote C<'+as'> when using this attribute.
4344 Not doing so causes Perl to incorrectly interpret C<+as> as a bareword
4345 with a unary plus operator before it, which is the same as simply C<as>.
4349 =item Value: \@extra_inflation_names
4353 Indicates additional inflation names for selectors added via L</+select>. See L</as>.
4359 =item Value: ($rel_name | \@rel_names | \%rel_names)
4363 Contains a list of relationships that should be joined for this query. For
4366 # Get CDs by Nine Inch Nails
4367 my $rs = $schema->resultset('CD')->search(
4368 { 'artist.name' => 'Nine Inch Nails' },
4369 { join => 'artist' }
4372 Can also contain a hash reference to refer to the other relation's relations.
4375 package MyApp::Schema::Track;
4376 use base qw/DBIx::Class/;
4377 __PACKAGE__->table('track');
4378 __PACKAGE__->add_columns(qw/trackid cd position title/);
4379 __PACKAGE__->set_primary_key('trackid');
4380 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
4383 # In your application
4384 my $rs = $schema->resultset('Artist')->search(
4385 { 'track.title' => 'Teardrop' },
4387 join => { cd => 'track' },
4388 order_by => 'artist.name',
4392 You need to use the relationship (not the table) name in conditions,
4393 because they are aliased as such. The current table is aliased as "me", so
4394 you need to use me.column_name in order to avoid ambiguity. For example:
4396 # Get CDs from 1984 with a 'Foo' track
4397 my $rs = $schema->resultset('CD')->search(
4400 'tracks.name' => 'Foo'
4402 { join => 'tracks' }
4405 If the same join is supplied twice, it will be aliased to <rel>_2 (and
4406 similarly for a third time). For e.g.
4408 my $rs = $schema->resultset('Artist')->search({
4409 'cds.title' => 'Down to Earth',
4410 'cds_2.title' => 'Popular',
4412 join => [ qw/cds cds/ ],
4415 will return a set of all artists that have both a cd with title 'Down
4416 to Earth' and a cd with title 'Popular'.
4418 If you want to fetch related objects from other tables as well, see L</prefetch>
4421 NOTE: An internal join-chain pruner will discard certain joins while
4422 constructing the actual SQL query, as long as the joins in question do not
4423 affect the retrieved result. This for example includes 1:1 left joins
4424 that are not part of the restriction specification (WHERE/HAVING) nor are
4425 a part of the query selection.
4427 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4433 =item Value: (0 | 1)
4437 When set to a true value, indicates that any rows fetched from joined has_many
4438 relationships are to be aggregated into the corresponding "parent" object. For
4439 example, the resultset:
4441 my $rs = $schema->resultset('CD')->search({}, {
4442 '+columns' => [ qw/ tracks.title tracks.position / ],
4447 While executing the following query:
4449 SELECT me.*, tracks.title, tracks.position
4451 LEFT JOIN track tracks
4452 ON tracks.cdid = me.cdid
4454 Will return only as many objects as there are rows in the CD source, even
4455 though the result of the query may span many rows. Each of these CD objects
4456 will in turn have multiple "Track" objects hidden behind the has_many
4457 generated accessor C<tracks>. Without C<< collapse => 1 >>, the return values
4458 of this resultset would be as many CD objects as there are tracks (a "Cartesian
4459 product"), with each CD object containing exactly one of all fetched Track data.
4461 When a collapse is requested on a non-ordered resultset, an order by some
4462 unique part of the main source (the left-most table) is inserted automatically.
4463 This is done so that the resultset is allowed to be "lazy" - calling
4464 L<< $rs->next|/next >> will fetch only as many rows as it needs to build the next
4465 object with all of its related data.
4467 If an L</order_by> is already declared, and orders the resultset in a way that
4468 makes collapsing as described above impossible (e.g. C<< ORDER BY
4469 has_many_rel.column >> or C<ORDER BY RANDOM()>), DBIC will automatically
4470 switch to "eager" mode and slurp the entire resultset before constructing the
4471 first object returned by L</next>.
4473 Setting this attribute on a resultset that does not join any has_many
4474 relations is a no-op.
4476 For a more in-depth discussion, see L</PREFETCHING>.
4482 =item Value: ($rel_name | \@rel_names | \%rel_names)
4486 This attribute is a shorthand for specifying a L</join> spec, adding all
4487 columns from the joined related sources as L</+columns> and setting
4488 L</collapse> to a true value. It can be thought of as a rough B<superset>
4489 of the L</join> attribute.
4491 For example, the following two queries are equivalent:
4493 my $rs = $schema->resultset('Artist')->search({}, {
4494 prefetch => { cds => ['genre', 'tracks' ] },
4499 my $rs = $schema->resultset('Artist')->search({}, {
4500 join => { cds => ['genre', 'tracks' ] },
4504 { +{ "cds.$_" => "cds.$_" } }
4505 $schema->source('Artist')->related_source('cds')->columns
4508 { +{ "cds.genre.$_" => "genre.$_" } }
4509 $schema->source('Artist')->related_source('cds')->related_source('genre')->columns
4512 { +{ "cds.tracks.$_" => "tracks.$_" } }
4513 $schema->source('Artist')->related_source('cds')->related_source('tracks')->columns
4518 Both producing the following SQL:
4520 SELECT me.artistid, me.name, me.rank, me.charfield,
4521 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track,
4522 genre.genreid, genre.name,
4523 tracks.trackid, tracks.cd, tracks.position, tracks.title, tracks.last_updated_on, tracks.last_updated_at
4526 ON cds.artist = me.artistid
4527 LEFT JOIN genre genre
4528 ON genre.genreid = cds.genreid
4529 LEFT JOIN track tracks
4530 ON tracks.cd = cds.cdid
4531 ORDER BY me.artistid
4533 While L</prefetch> implies a L</join>, it is ok to mix the two together, as
4534 the arguments are properly merged and generally do the right thing. For
4535 example, you may want to do the following:
4537 my $artists_and_cds_without_genre = $schema->resultset('Artist')->search(
4538 { 'genre.genreid' => undef },
4540 join => { cds => 'genre' },
4545 Which generates the following SQL:
4547 SELECT me.artistid, me.name, me.rank, me.charfield,
4548 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track
4551 ON cds.artist = me.artistid
4552 LEFT JOIN genre genre
4553 ON genre.genreid = cds.genreid
4554 WHERE genre.genreid IS NULL
4555 ORDER BY me.artistid
4557 For a more in-depth discussion, see L</PREFETCHING>.
4563 =item Value: $source_alias
4567 Sets the source alias for the query. Normally, this defaults to C<me>, but
4568 nested search queries (sub-SELECTs) might need specific aliases set to
4569 reference inner queries. For example:
4572 ->related_resultset('CDs')
4573 ->related_resultset('Tracks')
4575 'track.id' => { -ident => 'none_search.id' },
4579 my $ids = $self->search({
4582 alias => 'none_search',
4583 group_by => 'none_search.id',
4584 })->get_column('id')->as_query;
4586 $self->search({ id => { -in => $ids } })
4588 This attribute is directly tied to L</current_source_alias>.
4598 Makes the resultset paged and specifies the page to retrieve. Effectively
4599 identical to creating a non-pages resultset and then calling ->page($page)
4602 If L</rows> attribute is not specified it defaults to 10 rows per page.
4604 When you have a paged resultset, L</count> will only return the number
4605 of rows in the page. To get the total, use the L</pager> and call
4606 C<total_entries> on it.
4616 Specifies the maximum number of rows for direct retrieval or the number of
4617 rows per page if the page attribute or method is used.
4623 =item Value: $offset
4627 Specifies the (zero-based) row number for the first row to be returned, or the
4628 of the first row of the first page if paging is used.
4630 =head2 software_limit
4634 =item Value: (0 | 1)
4638 When combined with L</rows> and/or L</offset> the generated SQL will not
4639 include any limit dialect stanzas. Instead the entire result will be selected
4640 as if no limits were specified, and DBIC will perform the limit locally, by
4641 artificially advancing and finishing the resulting L</cursor>.
4643 This is the recommended way of performing resultset limiting when no sane RDBMS
4644 implementation is available (e.g.
4645 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4646 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4652 =item Value: \@columns
4656 A arrayref of columns to group by. Can include columns of joined tables.
4658 group_by => [qw/ column1 column2 ... /]
4664 =item Value: $condition
4668 The HAVING operator specifies a B<secondary> condition applied to the set
4669 after the grouping calculations have been done. In other words it is a
4670 constraint just like L</where> (and accepting the same
4671 L<SQL::Abstract syntax|SQL::Abstract/WHERE CLAUSES>) applied to the data
4672 as it exists after GROUP BY has taken place. Specifying L</having> without
4673 L</group_by> is a logical mistake, and a fatal error on most RDBMS engines.
4677 having => { 'count_employee' => { '>=', 100 } }
4679 or with an in-place function in which case literal SQL is required:
4681 having => \[ 'count(employee) >= ?', 100 ]
4687 =item Value: (0 | 1)
4691 Set to 1 to automatically generate a L</group_by> clause based on the selection
4692 (including intelligent handling of L</order_by> contents). Note that the group
4693 criteria calculation takes place over the B<final> selection. This includes
4694 any L</+columns>, L</+select> or L</order_by> additions in subsequent
4695 L</search> calls, and standalone columns selected via
4696 L<DBIx::Class::ResultSetColumn> (L</get_column>). A notable exception are the
4697 extra selections specified via L</prefetch> - such selections are explicitly
4698 excluded from group criteria calculations.
4700 If the final ResultSet also explicitly defines a L</group_by> attribute, this
4701 setting is ignored and an appropriate warning is issued.
4705 Adds extra conditions to the resultset, combined with the preexisting C<WHERE>
4706 conditions, same as the B<first> argument to the L<search operator|/search>
4708 # only return rows WHERE deleted IS NULL for all searches
4709 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4711 Note that the above example is
4712 L<strongly discouraged|DBIx::Class::ResultSource/resultset_attributes>.
4716 Set to 1 to cache search results. This prevents extra SQL queries if you
4717 revisit rows in your ResultSet:
4719 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4721 while( my $artist = $resultset->next ) {
4725 $resultset->first; # without cache, this would issue a query
4727 By default, searches are not cached.
4729 For more examples of using these attributes, see
4730 L<DBIx::Class::Manual::Cookbook>.
4736 =item Value: ( 'update' | 'shared' | \$scalar )
4740 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4741 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4746 DBIx::Class supports arbitrary related data prefetching from multiple related
4747 sources. Any combination of relationship types and column sets are supported.
4748 If L<collapsing|/collapse> is requested, there is an additional requirement of
4749 selecting enough data to make every individual object uniquely identifiable.
4751 Here are some more involved examples, based on the following relationship map:
4754 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4755 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4756 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4758 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4760 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4764 my $rs = $schema->resultset('Tag')->search(
4773 The initial search results in SQL like the following:
4775 SELECT tag.*, cd.*, artist.* FROM tag
4776 JOIN cd ON tag.cd = cd.cdid
4777 JOIN artist ON cd.artist = artist.artistid
4779 L<DBIx::Class> has no need to go back to the database when we access the
4780 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4783 Simple prefetches will be joined automatically, so there is no need
4784 for a C<join> attribute in the above search.
4786 The L</prefetch> attribute can be used with any of the relationship types
4787 and multiple prefetches can be specified together. Below is a more complex
4788 example that prefetches a CD's artist, its liner notes (if present),
4789 the cover image, the tracks on that CD, and the guests on those
4792 my $rs = $schema->resultset('CD')->search(
4796 { artist => 'record_label'}, # belongs_to => belongs_to
4797 'liner_note', # might_have
4798 'cover_image', # has_one
4799 { tracks => 'guests' }, # has_many => has_many
4804 This will produce SQL like the following:
4806 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4810 ON artist.artistid = me.artistid
4811 JOIN record_label record_label
4812 ON record_label.labelid = artist.labelid
4813 LEFT JOIN track tracks
4814 ON tracks.cdid = me.cdid
4815 LEFT JOIN guest guests
4816 ON guests.trackid = track.trackid
4817 LEFT JOIN liner_notes liner_note
4818 ON liner_note.cdid = me.cdid
4819 JOIN cd_artwork cover_image
4820 ON cover_image.cdid = me.cdid
4823 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4824 C<tracks>, and C<guests> of the CD will all be available through the
4825 relationship accessors without the need for additional queries to the
4830 Prefetch does a lot of deep magic. As such, it may not behave exactly
4831 as you might expect.
4837 Prefetch uses the L</cache> to populate the prefetched relationships. This
4838 may or may not be what you want.
4842 If you specify a condition on a prefetched relationship, ONLY those
4843 rows that match the prefetched condition will be fetched into that relationship.
4844 This means that adding prefetch to a search() B<may alter> what is returned by
4845 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4847 my $artist_rs = $schema->resultset('Artist')->search({
4853 my $count = $artist_rs->first->cds->count;
4855 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4857 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4859 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4861 That cmp_ok() may or may not pass depending on the datasets involved. In other
4862 words the C<WHERE> condition would apply to the entire dataset, just like
4863 it would in regular SQL. If you want to add a condition only to the "right side"
4864 of a C<LEFT JOIN> - consider declaring and using a L<relationship with a custom
4865 condition|DBIx::Class::Relationship::Base/condition>
4869 =head1 DBIC BIND VALUES
4871 Because DBIC may need more information to bind values than just the column name
4872 and value itself, it uses a special format for both passing and receiving bind
4873 values. Each bind value should be composed of an arrayref of
4874 C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
4880 If present (in any form), this is what is being passed directly to bind_param.
4881 Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
4882 a single numerical type, while DBD::Pg takes a hashref if bind options.)
4884 If this is specified, all other bind options described below are ignored.
4888 If present, this is used to infer the actual bind attribute by passing to
4889 C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
4890 "data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
4892 Note that the data type is somewhat freeform (hence the sqlt_ prefix);
4893 currently drivers are expected to "Do the Right Thing" when given a common
4894 datatype name. (Not ideal, but that's what we got at this point.)
4898 Currently used to correctly allocate buffers for bind_param_inout().
4899 Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
4900 or to a sensible value based on the "data_type".
4904 Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
4905 explicitly specified they are never overridden). Also used by some weird DBDs,
4906 where the column name should be available at bind_param time (e.g. Oracle).
4910 For backwards compatibility and convenience, the following shortcuts are
4913 [ $name => $val ] === [ { dbic_colname => $name }, $val ]
4914 [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
4915 [ undef, $val ] === [ {}, $val ]
4916 $val === [ {}, $val ]
4918 =head1 FURTHER QUESTIONS?
4920 Check the list of L<additional DBIC resources|DBIx::Class/GETTING HELP/SUPPORT>.
4922 =head1 COPYRIGHT AND LICENSE
4924 This module is free software L<copyright|DBIx::Class/COPYRIGHT AND LICENSE>
4925 by the L<DBIx::Class (DBIC) authors|DBIx::Class/AUTHORS>. You can
4926 redistribute it and/or modify it under the same terms as the
4927 L<DBIx::Class library|DBIx::Class/COPYRIGHT AND LICENSE>.