1 package DBIx::Class::ResultSet;
5 use base qw/DBIx::Class/;
7 use DBIx::Class::ResultSetColumn;
8 use DBIx::Class::ResultClass::HashRefInflator;
9 use Scalar::Util qw/blessed weaken reftype/;
10 use DBIx::Class::_Util qw(
11 dbic_internal_try dump_value
12 fail_on_internal_wantarray fail_on_internal_call UNRESOLVABLE_CONDITION
16 # not importing first() as it will clash with our own method
20 # De-duplication in _merge_attr() is disabled, but left in for reference
21 # (the merger is used for other things that ought not to be de-duped)
22 *__HM_DEDUP = sub () { 0 };
32 # this is real - CDBICompat overrides it with insanity
33 # yes, prototype won't matter, but that's for now ;)
36 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class result_source/);
40 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
44 my $users_rs = $schema->resultset('User');
45 while( $user = $users_rs->next) {
46 print $user->username;
49 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
50 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
54 A ResultSet is an object which stores a set of conditions representing
55 a query. It is the backbone of DBIx::Class (i.e. the really
56 important/useful bit).
58 No SQL is executed on the database when a ResultSet is created, it
59 just stores all the conditions needed to create the query.
61 A basic ResultSet representing the data of an entire table is returned
62 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
63 L<Source|DBIx::Class::Manual::Glossary/ResultSource> name.
65 my $users_rs = $schema->resultset('User');
67 A new ResultSet is returned from calling L</search> on an existing
68 ResultSet. The new one will contain all the conditions of the
69 original, plus any new conditions added in the C<search> call.
71 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
72 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
75 The query that the ResultSet represents is B<only> executed against
76 the database when these methods are called:
77 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
79 If a resultset is used in a numeric context it returns the L</count>.
80 However, if it is used in a boolean context it is B<always> true. So if
81 you want to check if a resultset has any results, you must use C<if $rs
86 =head2 Chaining resultsets
88 Let's say you've got a query that needs to be run to return some data
89 to the user. But, you have an authorization system in place that
90 prevents certain users from seeing certain information. So, you want
91 to construct the basic query in one method, but add constraints to it in
96 my $request = $self->get_request; # Get a request object somehow.
97 my $schema = $self->result_source->schema;
99 my $cd_rs = $schema->resultset('CD')->search({
100 title => $request->param('title'),
101 year => $request->param('year'),
104 $cd_rs = $self->apply_security_policy( $cd_rs );
106 return $cd_rs->all();
109 sub apply_security_policy {
118 =head3 Resolving conditions and attributes
120 When a resultset is chained from another resultset (e.g.:
121 C<< my $new_rs = $old_rs->search(\%extra_cond, \%attrs) >>), conditions
122 and attributes with the same keys need resolving.
124 If any of L</columns>, L</select>, L</as> are present, they reset the
125 original selection, and start the selection "clean".
127 The L</join>, L</prefetch>, L</+columns>, L</+select>, L</+as> attributes
128 are merged into the existing ones from the original resultset.
130 The L</where> and L</having> attributes, and any search conditions, are
131 merged with an SQL C<AND> to the existing condition from the original
134 All other attributes are overridden by any new ones supplied in the
137 =head2 Multiple queries
139 Since a resultset just defines a query, you can do all sorts of
140 things with it with the same object.
142 # Don't hit the DB yet.
143 my $cd_rs = $schema->resultset('CD')->search({
144 title => 'something',
148 # Each of these hits the DB individually.
149 my $count = $cd_rs->count;
150 my $most_recent = $cd_rs->get_column('date_released')->max();
151 my @records = $cd_rs->all;
153 And it's not just limited to SELECT statements.
159 $cd_rs->create({ artist => 'Fred' });
161 Which is the same as:
163 $schema->resultset('CD')->create({
164 title => 'something',
169 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
171 =head2 Custom ResultSet classes
173 To add methods to your resultsets, you can subclass L<DBIx::Class::ResultSet>, similar to:
175 package MyApp::Schema::ResultSet::User;
180 use base 'DBIx::Class::ResultSet';
184 $self->search({ $self->current_source_alias . '.active' => 1 });
189 $self->search({ $self->current_source_alias . '.verified' => 0 });
192 sub created_n_days_ago {
193 my ($self, $days_ago) = @_;
195 $self->current_source_alias . '.create_date' => {
197 $self->result_source->schema->storage->datetime_parser->format_datetime(
198 DateTime->now( time_zone => 'UTC' )->subtract( days => $days_ago )
203 sub users_to_warn { shift->active->unverified->created_n_days_ago(7) }
207 See L<DBIx::Class::Schema/load_namespaces> on how DBIC can discover and
208 automatically attach L<Result|DBIx::Class::Manual::ResultClass>-specific
209 L<ResulSet|DBIx::Class::ResultSet> classes.
211 =head3 ResultSet subclassing with Moose and similar constructor-providers
213 Using L<Moose> or L<Moo> in your ResultSet classes is usually overkill, but
214 you may find it useful if your ResultSets contain a lot of business logic
215 (e.g. C<has xml_parser>, C<has json>, etc) or if you just prefer to organize
218 In order to write custom ResultSet classes with L<Moo> you need to use the
219 following template. The L<BUILDARGS|Moo/BUILDARGS> is necessary due to the
220 unusual signature of the L<constructor provided by DBIC
221 |DBIx::Class::ResultSet/new> C<< ->new($source, \%args) >>.
224 extends 'DBIx::Class::ResultSet';
225 sub BUILDARGS { $_[2] } # ::RS::new() expects my ($class, $rsrc, $args) = @_
231 If you want to build your custom ResultSet classes with L<Moose>, you need
232 a similar, though a little more elaborate template in order to interface the
233 inlining of the L<Moose>-provided
234 L<object constructor|Moose::Manual::Construction/WHERE'S THE CONSTRUCTOR?>,
237 package MyApp::Schema::ResultSet::User;
240 use MooseX::NonMoose;
241 extends 'DBIx::Class::ResultSet';
243 sub BUILDARGS { $_[2] } # ::RS::new() expects my ($class, $rsrc, $args) = @_
247 __PACKAGE__->meta->make_immutable;
251 The L<MooseX::NonMoose> is necessary so that the L<Moose> constructor does not
252 entirely overwrite the DBIC one (in contrast L<Moo> does this automatically).
253 Alternatively, you can skip L<MooseX::NonMoose> and get by with just L<Moose>
256 __PACKAGE__->meta->make_immutable(inline_constructor => 0);
264 =item Arguments: L<$source|DBIx::Class::ResultSource>, L<\%attrs?|/ATTRIBUTES>
266 =item Return Value: L<$resultset|/search>
270 The resultset constructor. Takes a source object (usually a
271 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
272 L</ATTRIBUTES> below). Does not perform any queries -- these are
273 executed as needed by the other methods.
275 Generally you never construct a resultset manually. Instead you get one
277 C<< $schema->L<resultset|DBIx::Class::Schema/resultset>('$source_name') >>
278 or C<< $another_resultset->L<search|/search>(...) >> (the later called in
281 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
287 If called on an object, proxies to L</new_result> instead, so
289 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
291 will return a CD object, not a ResultSet, and is equivalent to:
293 my $cd = $schema->resultset('CD')->new_result({ title => 'Spoon' });
295 Please also keep in mind that many internals call L</new_result> directly,
296 so overloading this method with the idea of intercepting new result object
297 creation B<will not work>. See also warning pertaining to L</create>.
307 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
308 return $class->new_result(@_);
311 my ($source, $attrs) = @_;
312 $source = $source->resolve
313 if $source->isa('DBIx::Class::ResultSourceHandle');
315 $attrs = { %{$attrs||{}} };
316 delete @{$attrs}{qw(_last_sqlmaker_alias_map _simple_passthrough_construction)};
318 if ($attrs->{page}) {
319 $attrs->{rows} ||= 10;
322 $attrs->{alias} ||= 'me';
325 result_source => $source,
326 cond => $attrs->{where},
331 # if there is a dark selector, this means we are already in a
332 # chain and the cleanup/sanification was taken care of by
334 $self->_normalize_selection($attrs)
335 unless $attrs->{_dark_selector};
338 $attrs->{result_class} || $source->result_class
348 =item Arguments: L<$cond|DBIx::Class::SQLMaker> | undef, L<\%attrs?|/ATTRIBUTES>
350 =item Return Value: $resultset (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
354 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
355 my $new_rs = $cd_rs->search({ year => 2005 });
357 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
358 # year = 2005 OR year = 2004
360 In list context, C<< ->all() >> is called implicitly on the resultset, thus
361 returning a list of L<result|DBIx::Class::Manual::ResultClass> objects instead.
362 To avoid that, use L</search_rs>.
364 If you need to pass in additional attributes but no additional condition,
365 call it as C<search(undef, \%attrs)>.
367 # "SELECT name, artistid FROM $artist_table"
368 my @all_artists = $schema->resultset('Artist')->search(undef, {
369 columns => [qw/name artistid/],
372 For a list of attributes that can be passed to C<search>, see
373 L</ATTRIBUTES>. For more examples of using this function, see
374 L<Searching|DBIx::Class::Manual::Cookbook/SEARCHING>. For a complete
375 documentation for the first argument, see L<SQL::Abstract/"WHERE CLAUSES">
376 and its extension L<DBIx::Class::SQLMaker>.
378 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
382 Note that L</search> does not process/deflate any of the values passed in the
383 L<SQL::Abstract>-compatible search condition structure. This is unlike other
384 condition-bound methods L</new_result>, L</create> and L</find>. The user must ensure
385 manually that any value passed to this method will stringify to something the
386 RDBMS knows how to deal with. A notable example is the handling of L<DateTime>
387 objects, for more info see:
388 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
394 my $rs = $self->search_rs( @_ );
397 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_WANTARRAY and my $sog = fail_on_internal_wantarray;
400 elsif (defined wantarray) {
404 # we can be called by a relationship helper, which in
405 # turn may be called in void context due to some braindead
406 # overload or whatever else the user decided to be clever
407 # at this particular day. Thus limit the exception to
408 # external code calls only
409 $self->throw_exception ('->search is *not* a mutator, calling it in void context makes no sense')
410 if (caller)[0] !~ /^\QDBIx::Class::/;
420 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
422 =item Return Value: L<$resultset|/search>
426 This method does the same exact thing as search() except it will
427 always return a resultset, even in list context.
434 my $rsrc = $self->result_source;
435 my ($call_cond, $call_attrs);
437 # Special-case handling for (undef, undef) or (undef)
438 # Note that (foo => undef) is valid deprecated syntax
439 @_ = () if not scalar grep { defined $_ } @_;
445 # fish out attrs in the ($condref, $attr) case
446 elsif (@_ == 2 and ( ! defined $_[0] or length ref $_[0] ) ) {
447 ($call_cond, $call_attrs) = @_;
450 $self->throw_exception('Odd number of arguments to search')
454 carp_unique 'search( %condition ) is deprecated, use search( \%condition ) instead'
455 unless $rsrc->result_class->isa('DBIx::Class::CDBICompat');
457 for my $i (0 .. $#_) {
459 $self->throw_exception ('All keys in condition key/value pairs must be plain scalars')
460 if (! defined $_[$i] or length ref $_[$i] );
466 # see if we can keep the cache (no $rs changes)
468 my %safe = (alias => 1, cache => 1);
469 if ( ! List::Util::first { !$safe{$_} } keys %$call_attrs and (
472 ref $call_cond eq 'HASH' && ! keys %$call_cond
474 ref $call_cond eq 'ARRAY' && ! @$call_cond
476 $cache = $self->get_cache;
479 my $old_attrs = { %{$self->{attrs}} };
480 my ($old_having, $old_where) = delete @{$old_attrs}{qw(having where)};
482 my $new_attrs = { %$old_attrs };
484 # take care of call attrs (only if anything is changing)
485 if ($call_attrs and keys %$call_attrs) {
487 # copy for _normalize_selection
488 $call_attrs = { %$call_attrs };
490 my @selector_attrs = qw/select as columns cols +select +as +columns include_columns/;
492 # reset the current selector list if new selectors are supplied
493 if (List::Util::first { exists $call_attrs->{$_} } qw/columns cols select as/) {
494 delete @{$old_attrs}{(@selector_attrs, '_dark_selector')};
497 # Normalize the new selector list (operates on the passed-in attr structure)
498 # Need to do it on every chain instead of only once on _resolved_attrs, in
499 # order to allow detection of empty vs partial 'as'
500 $call_attrs->{_dark_selector} = $old_attrs->{_dark_selector}
501 if $old_attrs->{_dark_selector};
502 $self->_normalize_selection ($call_attrs);
504 # start with blind overwriting merge, exclude selector attrs
505 $new_attrs = { %{$old_attrs}, %{$call_attrs} };
506 delete @{$new_attrs}{@selector_attrs};
508 for (@selector_attrs) {
509 $new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
510 if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
513 # older deprecated name, use only if {columns} is not there
514 if (my $c = delete $new_attrs->{cols}) {
515 carp_unique( "Resultset attribute 'cols' is deprecated, use 'columns' instead" );
516 if ($new_attrs->{columns}) {
517 carp "Resultset specifies both the 'columns' and the legacy 'cols' attributes - ignoring 'cols'";
520 $new_attrs->{columns} = $c;
525 # join/prefetch use their own crazy merging heuristics
526 foreach my $key (qw/join prefetch/) {
527 $new_attrs->{$key} = $self->_merge_joinpref_attr($old_attrs->{$key}, $call_attrs->{$key})
528 if exists $call_attrs->{$key};
531 # stack binds together
532 $new_attrs->{bind} = [ @{ $old_attrs->{bind} || [] }, @{ $call_attrs->{bind} || [] } ];
536 for ($old_where, $call_cond) {
538 $new_attrs->{where} = $self->_stack_cond (
539 $_, $new_attrs->{where}
544 if (defined $old_having) {
545 $new_attrs->{having} = $self->_stack_cond (
546 $old_having, $new_attrs->{having}
550 my $rs = (ref $self)->new($rsrc, $new_attrs);
552 $rs->set_cache($cache) if ($cache);
557 sub _normalize_selection {
558 my ($self, $attrs) = @_;
561 if ( exists $attrs->{include_columns} ) {
562 carp_unique( "Resultset attribute 'include_columns' is deprecated, use '+columns' instead" );
563 $attrs->{'+columns'} = $self->_merge_attr(
564 $attrs->{'+columns'}, delete $attrs->{include_columns}
568 # columns are always placed first, however
570 # Keep the X vs +X separation until _resolved_attrs time - this allows to
571 # delay the decision on whether to use a default select list ($rsrc->columns)
572 # allowing stuff like the remove_columns helper to work
574 # select/as +select/+as pairs need special handling - the amount of select/as
575 # elements in each pair does *not* have to be equal (think multicolumn
576 # selectors like distinct(foo, bar) ). If the selector is bare (no 'as'
577 # supplied at all) - try to infer the alias, either from the -as parameter
578 # of the selector spec, or use the parameter whole if it looks like a column
579 # name (ugly legacy heuristic). If all fails - leave the selector bare (which
580 # is ok as well), but make sure no more additions to the 'as' chain take place
581 for my $pref ('', '+') {
583 my ($sel, $as) = map {
584 my $key = "${pref}${_}";
586 my $val = [ ref $attrs->{$key} eq 'ARRAY'
588 : $attrs->{$key} || ()
590 delete $attrs->{$key};
594 if (! @$as and ! @$sel ) {
597 elsif (@$as and ! @$sel) {
598 $self->throw_exception(
599 "Unable to handle ${pref}as specification (@$as) without a corresponding ${pref}select"
603 # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
604 # if any @$as has been supplied we assume the user knows what (s)he is doing
605 # and blindly keep stacking up pieces
606 unless ($attrs->{_dark_selector}) {
609 if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
610 push @$as, $_->{-as};
612 # assume any plain no-space, no-parenthesis string to be a column spec
613 # FIXME - this is retarded but is necessary to support shit like 'count(foo)'
614 elsif ( ! ref $_ and $_ =~ /^ [^\s\(\)]+ $/x) {
617 # if all else fails - raise a flag that no more aliasing will be allowed
619 $attrs->{_dark_selector} = {
622 local $Data::Dumper::Indent = 0;
631 elsif (@$as < @$sel) {
632 $self->throw_exception(
633 "Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
636 elsif ($pref and $attrs->{_dark_selector}) {
637 $self->throw_exception(
638 "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
644 $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
645 $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
650 my ($self, $left, $right) = @_;
653 (ref $_ eq 'ARRAY' and !@$_)
655 (ref $_ eq 'HASH' and ! keys %$_)
656 ) and $_ = undef for ($left, $right);
658 # either one of the two undef
659 if ( (defined $left) xor (defined $right) ) {
660 return defined $left ? $left : $right;
663 elsif ( ! defined $left ) {
667 return $self->result_source->schema->storage->_collapse_cond({ -and => [$left, $right] });
671 =head2 search_literal
673 B<CAVEAT>: C<search_literal> is provided for Class::DBI compatibility and
674 should only be used in that context. C<search_literal> is a convenience
675 method. It is equivalent to calling C<< $schema->search(\[]) >>, but if you
676 want to ensure columns are bound correctly, use L</search>.
678 See L<DBIx::Class::Manual::Cookbook/SEARCHING> and
679 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
680 require C<search_literal>.
684 =item Arguments: $sql_fragment, @standalone_bind_values
686 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
690 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
691 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
693 Pass a literal chunk of SQL to be added to the conditional part of the
696 Example of how to use C<search> instead of C<search_literal>
698 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
699 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
704 my ($self, $sql, @bind) = @_;
706 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
709 return $self->search(\[ $sql, map [ {} => $_ ], @bind ], ($attr || () ));
716 =item Arguments: \%columns_values | @pk_values, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
718 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
722 Finds and returns a single row based on supplied criteria. Takes either a
723 hashref with the same format as L</create> (including inference of foreign
724 keys from related objects), or a list of primary key values in the same
725 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
726 declaration on the L</result_source>.
728 In either case an attempt is made to combine conditions already existing on
729 the resultset with the condition passed to this method.
731 To aid with preparing the correct query for the storage you may supply the
732 C<key> attribute, which is the name of a
733 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
734 unique constraint corresponding to the
735 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
736 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
737 to construct a query that satisfies the named unique constraint fully (
738 non-NULL values for each column member of the constraint) an exception is
741 If no C<key> is specified, the search is carried over all unique constraints
742 which are fully defined by the available condition.
744 If no such constraint is found, C<find> currently defaults to a simple
745 C<< search->(\%column_values) >> which may or may not do what you expect.
746 Note that this fallback behavior may be deprecated in further versions. If
747 you need to search with arbitrary conditions - use L</search>. If the query
748 resulting from this fallback produces more than one row, a warning to the
749 effect is issued, though only the first row is constructed and returned as
752 In addition to C<key>, L</find> recognizes and applies standard
753 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
755 Note that if you have extra concerns about the correctness of the resulting
756 query you need to specify the C<key> attribute and supply the entire condition
757 as an argument to find (since it is not always possible to perform the
758 combination of the resultset condition with the supplied one, especially if
759 the resultset condition contains literal sql).
761 For example, to find a row by its primary key:
763 my $cd = $schema->resultset('CD')->find(5);
765 You can also find a row by a specific unique constraint:
767 my $cd = $schema->resultset('CD')->find(
769 artist => 'Massive Attack',
770 title => 'Mezzanine',
772 { key => 'cd_artist_title' }
775 See also L</find_or_create> and L</update_or_create>.
781 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
783 my $rsrc = $self->result_source;
786 if (exists $attrs->{key}) {
787 $constraint_name = defined $attrs->{key}
789 : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
793 # Parse out the condition from input
796 if (ref $_[0] eq 'HASH') {
797 $call_cond = { %{$_[0]} };
800 # if only values are supplied we need to default to 'primary'
801 $constraint_name = 'primary' unless defined $constraint_name;
803 my @c_cols = $rsrc->unique_constraint_columns($constraint_name);
805 $self->throw_exception(
806 "No constraint columns, maybe a malformed '$constraint_name' constraint?"
809 $self->throw_exception (
810 'find() expects either a column/value hashref, or a list of values '
811 . "corresponding to the columns of the specified unique constraint '$constraint_name'"
812 ) unless @c_cols == @_;
814 @{$call_cond}{@c_cols} = @_;
817 # process relationship data if any
818 for my $key (keys %$call_cond) {
820 length ref($call_cond->{$key})
822 my $relinfo = $rsrc->relationship_info($key)
824 # implicitly skip has_many's (likely MC)
825 (ref (my $val = delete $call_cond->{$key}) ne 'ARRAY' )
827 my ($rel_cond, $crosstable) = $rsrc->_resolve_condition(
828 $relinfo->{cond}, $val, $key, $key
831 $self->throw_exception("Complex condition via relationship '$key' is unsupported in find()")
832 if $crosstable or ref($rel_cond) ne 'HASH';
834 # supplement condition
835 # relationship conditions take precedence (?)
836 @{$call_cond}{keys %$rel_cond} = values %$rel_cond;
840 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
842 if (defined $constraint_name) {
843 $final_cond = $self->_qualify_cond_columns (
845 $self->result_source->_minimal_valueset_satisfying_constraint(
846 constraint_name => $constraint_name,
847 values => ($self->_merge_with_rscond($call_cond))[0],
854 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
855 # This means that we got here after a merger of relationship conditions
856 # in ::Relationship::Base::search_related (the row method), and furthermore
857 # the relationship is of the 'single' type. This means that the condition
858 # provided by the relationship (already attached to $self) is sufficient,
859 # as there can be only one row in the database that would satisfy the
863 my (@unique_queries, %seen_column_combinations, $ci, @fc_exceptions);
865 # no key was specified - fall down to heuristics mode:
866 # run through all unique queries registered on the resultset, and
867 # 'OR' all qualifying queries together
869 # always start from 'primary' if it exists at all
870 for my $c_name ( sort {
872 : $b eq 'primary' ? 1
874 } $rsrc->unique_constraint_names) {
876 next if $seen_column_combinations{
877 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
881 push @unique_queries, $self->_qualify_cond_columns(
882 $self->result_source->_minimal_valueset_satisfying_constraint(
883 constraint_name => $c_name,
884 values => ($self->_merge_with_rscond($call_cond))[0],
885 columns_info => ($ci ||= $self->result_source->columns_info),
891 push @fc_exceptions, $_ if $_ =~ /\bFilterColumn\b/;
896 @unique_queries ? \@unique_queries
897 : @fc_exceptions ? $self->throw_exception(join "; ", map { $_ =~ /(.*) at .+ line \d+$/s } @fc_exceptions )
898 : $self->_non_unique_find_fallback ($call_cond, $attrs)
902 # Run the query, passing the result_class since it should propagate for find
903 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
904 if ($rs->_resolved_attrs->{collapse}) {
906 carp "Query returned more than one row" if $rs->next;
914 # This is a stop-gap method as agreed during the discussion on find() cleanup:
915 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
917 # It is invoked when find() is called in legacy-mode with insufficiently-unique
918 # condition. It is provided for overrides until a saner way forward is devised
920 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
921 # the road. Please adjust your tests accordingly to catch this situation early
922 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
924 # The method will not be removed without an adequately complete replacement
925 # for strict-mode enforcement
926 sub _non_unique_find_fallback {
927 my ($self, $cond, $attrs) = @_;
929 return $self->_qualify_cond_columns(
931 exists $attrs->{alias}
933 : $self->{attrs}{alias}
938 sub _qualify_cond_columns {
939 my ($self, $cond, $alias) = @_;
941 my %aliased = %$cond;
942 for (keys %aliased) {
943 $aliased{"$alias.$_"} = delete $aliased{$_}
950 sub _build_unique_cond {
952 '_build_unique_cond is a private method, and moreover is about to go '
953 . 'away. Please contact the development team at %s if you believe you '
954 . 'have a genuine use for this method, in order to discuss alternatives.',
955 DBIx::Class::_ENV_::HELP_URL,
958 my ($self, $constraint_name, $cond, $croak_on_null) = @_;
960 $self->result_source->_minimal_valueset_satisfying_constraint(
961 constraint_name => $constraint_name,
963 carp_on_nulls => !$croak_on_null
967 =head2 search_related
971 =item Arguments: $rel_name, $cond?, L<\%attrs?|/ATTRIBUTES>
973 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
977 $new_rs = $cd_rs->search_related('artist', {
981 Searches the specified relationship, optionally specifying a condition and
982 attributes for matching records. See L</ATTRIBUTES> for more information.
984 In list context, C<< ->all() >> is called implicitly on the resultset, thus
985 returning a list of result objects instead. To avoid that, use L</search_related_rs>.
987 See also L</search_related_rs>.
992 return shift->related_resultset(shift)->search(@_);
995 =head2 search_related_rs
997 This method works exactly the same as search_related, except that
998 it guarantees a resultset, even in list context.
1002 sub search_related_rs {
1003 return shift->related_resultset(shift)->search_rs(@_);
1010 =item Arguments: none
1012 =item Return Value: L<$cursor|DBIx::Class::Cursor>
1016 Returns a storage-driven cursor to the given resultset. See
1017 L<DBIx::Class::Cursor> for more information.
1024 return $self->{cursor} ||= do {
1025 my $attrs = $self->_resolved_attrs;
1026 $self->result_source->storage->select(
1027 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
1036 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1038 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1042 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1044 Inflates the first result without creating a cursor if the resultset has
1045 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1048 While this method can take an optional search condition (just like L</search>)
1049 being a fast-code-path it does not recognize search attributes. If you need to
1050 add extra joins or similar, call L</search> and then chain-call L</single> on the
1051 L<DBIx::Class::ResultSet> returned.
1057 As of 0.08100, this method enforces the assumption that the preceding
1058 query returns only one row. If more than one row is returned, you will receive
1061 Query returned more than one row
1063 In this case, you should be using L</next> or L</find> instead, or if you really
1064 know what you are doing, use the L</rows> attribute to explicitly limit the size
1067 This method will also throw an exception if it is called on a resultset prefetching
1068 has_many, as such a prefetch implies fetching multiple rows from the database in
1069 order to assemble the resulting object.
1076 my ($self, $where) = @_;
1078 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1081 my $attrs = { %{$self->_resolved_attrs} };
1083 $self->throw_exception(
1084 'single() can not be used on resultsets collapsing a has_many. Use find( \%cond ) or next() instead'
1085 ) if $attrs->{collapse};
1088 if (defined $attrs->{where}) {
1091 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1092 $where, delete $attrs->{where} ]
1095 $attrs->{where} = $where;
1099 my $data = [ $self->result_source->storage->select_single(
1100 $attrs->{from}, $attrs->{select},
1101 $attrs->{where}, $attrs
1104 return undef unless @$data;
1105 $self->{_stashed_rows} = [ $data ];
1106 $self->_construct_results->[0];
1113 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1115 =item Return Value: L<$resultsetcolumn|DBIx::Class::ResultSetColumn>
1119 my $max_length = $rs->get_column('length')->max;
1121 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1126 my ($self, $column) = @_;
1127 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
1135 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1137 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1141 # WHERE title LIKE '%blue%'
1142 $cd_rs = $rs->search_like({ title => '%blue%'});
1144 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1145 that this is simply a convenience method retained for ex Class::DBI users.
1146 You most likely want to use L</search> with specific operators.
1148 For more information, see L<DBIx::Class::Manual::Cookbook>.
1150 This method is deprecated and will be removed in 0.09. Use L<search()|/search>
1151 instead. An example conversion is:
1153 ->search_like({ foo => 'bar' });
1157 ->search({ foo => { like => 'bar' } });
1164 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1165 .' Instead use ->search({ x => { -like => "y%" } })'
1166 .' (note the outer pair of {}s - they are important!)'
1168 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1169 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1170 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1171 return $class->search($query, { %$attrs });
1178 =item Arguments: $first, $last
1180 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1184 Returns a resultset or object list representing a subset of elements from the
1185 resultset slice is called on. Indexes are from 0, i.e., to get the first
1186 three records, call:
1188 my ($one, $two, $three) = $rs->slice(0, 2);
1193 my ($self, $min, $max) = @_;
1194 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1195 $attrs->{offset} = $self->{attrs}{offset} || 0;
1196 $attrs->{offset} += $min;
1197 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1198 return $self->search(undef, $attrs);
1205 =item Arguments: none
1207 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1211 Returns the next element in the resultset (C<undef> is there is none).
1213 Can be used to efficiently iterate over records in the resultset:
1215 my $rs = $schema->resultset('CD')->search;
1216 while (my $cd = $rs->next) {
1220 Note that you need to store the resultset object, and call C<next> on it.
1221 Calling C<< resultset('Table')->next >> repeatedly will always return the
1222 first record from the resultset.
1229 if (my $cache = $self->get_cache) {
1230 $self->{all_cache_position} ||= 0;
1231 return $cache->[$self->{all_cache_position}++];
1234 if ($self->{attrs}{cache}) {
1235 delete $self->{pager};
1236 $self->{all_cache_position} = 1;
1237 return ($self->all)[0];
1240 return shift(@{$self->{_stashed_results}}) if @{ $self->{_stashed_results}||[] };
1242 $self->{_stashed_results} = $self->_construct_results
1245 return shift @{$self->{_stashed_results}};
1248 # Constructs as many results as it can in one pass while respecting
1249 # cursor laziness. Several modes of operation:
1251 # * Always builds everything present in @{$self->{_stashed_rows}}
1252 # * If called with $fetch_all true - pulls everything off the cursor and
1253 # builds all result structures (or objects) in one pass
1254 # * If $self->_resolved_attrs->{collapse} is true, checks the order_by
1255 # and if the resultset is ordered properly by the left side:
1256 # * Fetches stuff off the cursor until the "master object" changes,
1257 # and saves the last extra row (if any) in @{$self->{_stashed_rows}}
1259 # * Just fetches, and collapses/constructs everything as if $fetch_all
1260 # was requested (there is no other way to collapse except for an
1262 # * If no collapse is requested - just get the next row, construct and
1264 sub _construct_results {
1265 my ($self, $fetch_all) = @_;
1267 my $rsrc = $self->result_source;
1268 my $attrs = $self->_resolved_attrs;
1273 ! $attrs->{order_by}
1277 my @pcols = $rsrc->primary_columns
1279 # default order for collapsing unless the user asked for something
1280 $attrs->{order_by} = [ map { join '.', $attrs->{alias}, $_} @pcols ];
1281 $attrs->{_ordered_for_collapse} = 1;
1282 $attrs->{_order_is_artificial} = 1;
1285 # this will be used as both initial raw-row collector AND as a RV of
1286 # _construct_results. Not regrowing the array twice matters a lot...
1287 # a surprising amount actually
1288 my $rows = delete $self->{_stashed_rows};
1290 my $cursor; # we may not need one at all
1292 my $did_fetch_all = $fetch_all;
1295 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1296 $rows = [ ($rows ? @$rows : ()), $self->cursor->all ];
1298 elsif( $attrs->{collapse} ) {
1300 # a cursor will need to be closed over in case of collapse
1301 $cursor = $self->cursor;
1303 $attrs->{_ordered_for_collapse} = (
1309 ->_extract_colinfo_of_stable_main_source_order_by_portion($attrs)
1311 ) unless defined $attrs->{_ordered_for_collapse};
1313 if (! $attrs->{_ordered_for_collapse}) {
1316 # instead of looping over ->next, use ->all in stealth mode
1317 # *without* calling a ->reset afterwards
1318 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1319 if (! $cursor->{_done}) {
1320 $rows = [ ($rows ? @$rows : ()), $cursor->all ];
1321 $cursor->{_done} = 1;
1326 if (! $did_fetch_all and ! @{$rows||[]} ) {
1327 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1328 $cursor ||= $self->cursor;
1329 if (scalar (my @r = $cursor->next) ) {
1334 return undef unless @{$rows||[]};
1336 # sanity check - people are too clever for their own good
1337 if ($attrs->{collapse} and my $aliastypes = $attrs->{_last_sqlmaker_alias_map} ) {
1339 my $multiplied_selectors;
1340 for my $sel_alias ( grep { $_ ne $attrs->{alias} } keys %{ $aliastypes->{selecting} } ) {
1342 $aliastypes->{multiplying}{$sel_alias}
1344 $aliastypes->{premultiplied}{$sel_alias}
1346 $multiplied_selectors->{$_} = 1 for values %{$aliastypes->{selecting}{$sel_alias}{-seen_columns}}
1350 for my $i (0 .. $#{$attrs->{as}} ) {
1351 my $sel = $attrs->{select}[$i];
1353 if (ref $sel eq 'SCALAR') {
1356 elsif( ref $sel eq 'REF' and ref $$sel eq 'ARRAY' ) {
1360 $self->throw_exception(
1361 'Result collapse not possible - selection from a has_many source redirected to the main object'
1362 ) if ($multiplied_selectors->{$sel} and $attrs->{as}[$i] !~ /\./);
1366 # hotspot - skip the setter
1367 my $res_class = $self->_result_class;
1369 my $inflator_cref = $self->{_result_inflator}{cref} ||= do {
1370 $res_class->can ('inflate_result')
1371 or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
1374 my $infmap = $attrs->{as};
1376 $self->{_result_inflator}{is_core_row} = ( (
1379 ( \&DBIx::Class::Row::inflate_result || die "No ::Row::inflate_result() - can't happen" )
1380 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_core_row};
1382 $self->{_result_inflator}{is_hri} = ( (
1383 ! $self->{_result_inflator}{is_core_row}
1385 $inflator_cref == \&DBIx::Class::ResultClass::HashRefInflator::inflate_result
1386 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_hri};
1389 if ($attrs->{_simple_passthrough_construction}) {
1390 # construct a much simpler array->hash folder for the one-table HRI cases right here
1391 if ($self->{_result_inflator}{is_hri}) {
1392 for my $r (@$rows) {
1393 $r = { map { $infmap->[$_] => $r->[$_] } 0..$#$infmap };
1396 # FIXME SUBOPTIMAL this is a very very very hot spot
1397 # while rather optimal we can *still* do much better, by
1398 # building a smarter Row::inflate_result(), and
1399 # switch to feeding it data via a much leaner interface
1401 # crude unscientific benchmarking indicated the shortcut eval is not worth it for
1402 # this particular resultset size
1403 elsif ( $self->{_result_inflator}{is_core_row} and @$rows < 60 ) {
1404 for my $r (@$rows) {
1405 $r = $inflator_cref->($res_class, $rsrc, { map { $infmap->[$_] => $r->[$_] } (0..$#$infmap) } );
1410 ( $self->{_result_inflator}{is_core_row}
1411 ? '$_ = $inflator_cref->($res_class, $rsrc, { %s }) for @$rows'
1412 # a custom inflator may be a multiplier/reductor - put it in direct list ctx
1413 : '@$rows = map { $inflator_cref->($res_class, $rsrc, { %s } ) } @$rows'
1415 ( join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap ) )
1421 $self->{_result_inflator}{is_hri} ? 'hri'
1422 : $self->{_result_inflator}{is_core_row} ? 'classic_pruning'
1423 : 'classic_nonpruning'
1426 # $args and $attrs to _mk_row_parser are separated to delineate what is
1427 # core collapser stuff and what is dbic $rs specific
1428 @{$self->{_row_parser}{$parser_type}}{qw(cref nullcheck)} = $rsrc->_mk_row_parser({
1430 inflate_map => $infmap,
1431 collapse => $attrs->{collapse},
1432 premultiplied => $attrs->{_main_source_premultiplied},
1433 hri_style => $self->{_result_inflator}{is_hri},
1434 prune_null_branches => $self->{_result_inflator}{is_hri} || $self->{_result_inflator}{is_core_row},
1435 }, $attrs) unless $self->{_row_parser}{$parser_type}{cref};
1437 # column_info metadata historically hasn't been too reliable.
1438 # We need to start fixing this somehow (the collapse resolver
1439 # can't work without it). Add an explicit check for the *main*
1440 # result, hopefully this will gradually weed out such errors
1442 # FIXME - this is a temporary kludge that reduces performance
1443 # It is however necessary for the time being
1444 my ($unrolled_non_null_cols_to_check, $err);
1446 if (my $check_non_null_cols = $self->{_row_parser}{$parser_type}{nullcheck} ) {
1449 'Collapse aborted due to invalid ResultSource metadata - the following '
1450 . 'selections are declared non-nullable but NULLs were retrieved: '
1454 COL: for my $i (@$check_non_null_cols) {
1455 ! defined $_->[$i] and push @violating_idx, $i and next COL for @$rows;
1458 $self->throw_exception( $err . join (', ', map { "'$infmap->[$_]'" } @violating_idx ) )
1461 $unrolled_non_null_cols_to_check = join (',', @$check_non_null_cols);
1463 utf8::upgrade($unrolled_non_null_cols_to_check)
1464 if DBIx::Class::_ENV_::STRESSTEST_UTF8_UPGRADE_GENERATED_COLLAPSER_SOURCE;
1468 ($did_fetch_all or ! $attrs->{collapse}) ? undef
1469 : defined $unrolled_non_null_cols_to_check ? eval sprintf <<'EOS', $unrolled_non_null_cols_to_check
1471 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1472 my @r = $cursor->next or return;
1473 if (my @violating_idx = grep { ! defined $r[$_] } (%s) ) {
1474 $self->throw_exception( $err . join (', ', map { "'$infmap->[$_]'" } @violating_idx ) )
1480 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1481 my @r = $cursor->next or return;
1486 $self->{_row_parser}{$parser_type}{cref}->(
1488 $next_cref ? ( $next_cref, $self->{_stashed_rows} = [] ) : (),
1491 # simple in-place substitution, does not regrow $rows
1492 if ($self->{_result_inflator}{is_core_row}) {
1493 $_ = $inflator_cref->($res_class, $rsrc, @$_) for @$rows
1495 # Special-case multi-object HRI - there is no $inflator_cref pass at all
1496 elsif ( ! $self->{_result_inflator}{is_hri} ) {
1497 # the inflator may be a multiplier/reductor - put it in list ctx
1498 @$rows = map { $inflator_cref->($res_class, $rsrc, @$_) } @$rows;
1502 # The @$rows check seems odd at first - why wouldn't we want to warn
1503 # regardless? The issue is things like find() etc, where the user
1504 # *knows* only one result will come back. In these cases the ->all
1505 # is not a pessimization, but rather something we actually want
1507 'Unable to properly collapse has_many results in iterator mode due '
1508 . 'to order criteria - performed an eager cursor slurp underneath. '
1509 . 'Consider using ->all() instead'
1510 ) if ( ! $fetch_all and @$rows > 1 );
1515 =head2 result_source
1519 =item Arguments: L<$result_source?|DBIx::Class::ResultSource>
1521 =item Return Value: L<$result_source|DBIx::Class::ResultSource>
1525 An accessor for the primary ResultSource object from which this ResultSet
1532 =item Arguments: $result_class?
1534 =item Return Value: $result_class
1538 An accessor for the class to use when creating result objects. Defaults to
1539 C<< result_source->result_class >> - which in most cases is the name of the
1540 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1542 Note that changing the result_class will also remove any components
1543 that were originally loaded in the source class via
1544 L<load_components|Class::C3::Componentised/load_components( @comps )>.
1545 Any overloaded methods in the original source class will not run.
1550 my ($self, $result_class) = @_;
1551 if ($result_class) {
1553 # don't fire this for an object
1554 $self->ensure_class_loaded($result_class)
1555 unless ref($result_class);
1557 if ($self->get_cache) {
1558 carp_unique('Changing the result_class of a ResultSet instance with cached results is a noop - the cache contents will not be altered');
1560 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1561 elsif ($self->{cursor} && $self->{cursor}{_pos}) {
1562 $self->throw_exception('Changing the result_class of a ResultSet instance with an active cursor is not supported');
1565 $self->_result_class($result_class);
1567 delete $self->{_result_inflator};
1569 $self->_result_class;
1576 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1578 =item Return Value: $count
1582 Performs an SQL C<COUNT> with the same query as the resultset was built
1583 with to find the number of elements. Passing arguments is equivalent to
1584 C<< $rs->search ($cond, \%attrs)->count >>
1590 return $self->search(@_)->count if @_ and defined $_[0];
1591 return scalar @{ $self->get_cache } if $self->get_cache;
1593 my $attrs = { %{ $self->_resolved_attrs } };
1595 # this is a little optimization - it is faster to do the limit
1596 # adjustments in software, instead of a subquery
1597 my ($rows, $offset) = delete @{$attrs}{qw/rows offset/};
1600 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1601 $crs = $self->_count_subq_rs ($attrs);
1604 $crs = $self->_count_rs ($attrs);
1606 my $count = $crs->next;
1608 $count -= $offset if $offset;
1609 $count = $rows if $rows and $rows < $count;
1610 $count = 0 if ($count < 0);
1619 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1621 =item Return Value: L<$count_rs|DBIx::Class::ResultSetColumn>
1625 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1626 This can be very handy for subqueries:
1628 ->search( { amount => $some_rs->count_rs->as_query } )
1630 As with regular resultsets the SQL query will be executed only after
1631 the resultset is accessed via L</next> or L</all>. That would return
1632 the same single value obtainable via L</count>.
1638 return $self->search(@_)->count_rs if @_;
1640 # this may look like a lack of abstraction (count() does about the same)
1641 # but in fact an _rs *must* use a subquery for the limits, as the
1642 # software based limiting can not be ported if this $rs is to be used
1643 # in a subquery itself (i.e. ->as_query)
1644 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1645 return $self->_count_subq_rs($self->{_attrs});
1648 return $self->_count_rs($self->{_attrs});
1653 # returns a ResultSetColumn object tied to the count query
1656 my ($self, $attrs) = @_;
1658 my $rsrc = $self->result_source;
1660 my $tmp_attrs = { %$attrs };
1661 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1662 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1664 # overwrite the selector (supplied by the storage)
1665 $rsrc->resultset_class->new($rsrc, {
1667 select => $rsrc->storage->_count_select ($rsrc, $attrs),
1669 })->get_column ('count');
1673 # same as above but uses a subquery
1675 sub _count_subq_rs {
1676 my ($self, $attrs) = @_;
1678 my $rsrc = $self->result_source;
1680 my $sub_attrs = { %$attrs };
1681 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1682 delete @{$sub_attrs}{qw/collapse columns as select order_by for/};
1684 # if we multi-prefetch we group_by something unique, as this is what we would
1685 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1686 if ( $attrs->{collapse} ) {
1687 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1688 $rsrc->_identifying_column_set || $self->throw_exception(
1689 'Unable to construct a unique group_by criteria properly collapsing the '
1690 . 'has_many prefetch before count()'
1695 # Calculate subquery selector
1696 if (my $g = $sub_attrs->{group_by}) {
1698 my $sql_maker = $rsrc->storage->sql_maker;
1700 # necessary as the group_by may refer to aliased functions
1702 for my $sel (@{$attrs->{select}}) {
1703 $sel_index->{$sel->{-as}} = $sel
1704 if (ref $sel eq 'HASH' and $sel->{-as});
1707 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1708 # also look for named aggregates referred in the having clause
1709 # having often contains scalarrefs - thus parse it out entirely
1711 if ($attrs->{having}) {
1712 local $sql_maker->{having_bind};
1713 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1714 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1715 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1716 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1717 # if we don't unset it we screw up retarded but unfortunately working
1718 # 'MAX(foo.bar)' => { '>', 3 }
1719 $sql_maker->{name_sep} = '';
1722 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1724 my $having_sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1727 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1728 # and if all fails for an utterly naive quoted scalar-with-function
1729 while ($having_sql =~ /
1730 $rquote $sep $lquote (.+?) $rquote
1732 [\s,] \w+ \. (\w+) [\s,]
1734 [\s,] $lquote (.+?) $rquote [\s,]
1736 my $part = $1 || $2 || $3; # one of them matched if we got here
1737 unless ($seen_having{$part}++) {
1744 my $colpiece = $sel_index->{$_} || $_;
1746 # unqualify join-based group_by's. Arcane but possible query
1747 # also horrible horrible hack to alias a column (not a func.)
1748 # (probably need to introduce SQLA syntax)
1749 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1752 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1754 push @{$sub_attrs->{select}}, $colpiece;
1758 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1759 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1762 return $rsrc->resultset_class
1763 ->new ($rsrc, $sub_attrs)
1765 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1766 ->get_column ('count');
1770 =head2 count_literal
1772 B<CAVEAT>: C<count_literal> is provided for Class::DBI compatibility and
1773 should only be used in that context. See L</search_literal> for further info.
1777 =item Arguments: $sql_fragment, @standalone_bind_values
1779 =item Return Value: $count
1783 Counts the results in a literal query. Equivalent to calling L</search_literal>
1784 with the passed arguments, then L</count>.
1788 sub count_literal { shift->search_literal(@_)->count; }
1794 =item Arguments: none
1796 =item Return Value: L<@result_objs|DBIx::Class::Manual::ResultClass>
1800 Returns all elements in the resultset.
1807 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1810 delete @{$self}{qw/_stashed_rows _stashed_results/};
1812 if (my $c = $self->get_cache) {
1816 $self->cursor->reset;
1818 my $objs = $self->_construct_results('fetch_all') || [];
1820 $self->set_cache($objs) if $self->{attrs}{cache};
1829 =item Arguments: none
1831 =item Return Value: $self
1835 Resets the resultset's cursor, so you can iterate through the elements again.
1836 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1844 delete @{$self}{qw/_stashed_rows _stashed_results/};
1845 $self->{all_cache_position} = 0;
1846 $self->cursor->reset;
1854 =item Arguments: none
1856 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1860 L<Resets|/reset> the resultset (causing a fresh query to storage) and returns
1861 an object for the first result (or C<undef> if the resultset is empty).
1866 return $_[0]->reset->next;
1872 # Determines whether and what type of subquery is required for the $rs operation.
1873 # If grouping is necessary either supplies its own, or verifies the current one
1874 # After all is done delegates to the proper storage method.
1876 sub _rs_update_delete {
1877 my ($self, $op, $values) = @_;
1879 my $rsrc = $self->result_source;
1880 my $storage = $rsrc->schema->storage;
1882 my $attrs = { %{$self->_resolved_attrs} };
1884 my $join_classifications;
1885 my ($existing_group_by) = delete @{$attrs}{qw(group_by _grouped_by_distinct)};
1887 # do we need a subquery for any reason?
1889 defined $existing_group_by
1891 # if {from} is unparseable wrap a subq
1892 ref($attrs->{from}) ne 'ARRAY'
1894 # limits call for a subq
1895 $self->_has_resolved_attr(qw/rows offset/)
1898 # simplify the joinmap, so we can further decide if a subq is necessary
1899 if (!$needs_subq and @{$attrs->{from}} > 1) {
1901 ($attrs->{from}, $join_classifications) =
1902 $storage->_prune_unused_joins ($attrs);
1904 # any non-pruneable non-local restricting joins imply subq
1905 $needs_subq = defined List::Util::first { $_ ne $attrs->{alias} } keys %{ $join_classifications->{restricting} || {} };
1908 # check if the head is composite (by now all joins are thrown out unless $needs_subq)
1910 (ref $attrs->{from}[0]) ne 'HASH'
1912 ref $attrs->{from}[0]{ $attrs->{from}[0]{-alias} }
1916 # do we need anything like a subquery?
1917 if (! $needs_subq) {
1918 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1919 # a condition containing 'me' or other table prefixes will not work
1920 # at all. Tell SQLMaker to dequalify idents via a gross hack.
1922 my $sqla = $rsrc->storage->sql_maker;
1923 local $sqla->{_dequalify_idents} = 1;
1924 \[ $sqla->_recurse_where($self->{cond}) ];
1928 # we got this far - means it is time to wrap a subquery
1929 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1931 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1937 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1938 delete $attrs->{$_} for qw/select as collapse/;
1939 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1941 # this will be consumed by the pruner waaaaay down the stack
1942 $attrs->{_force_prune_multiplying_joins} = 1;
1944 my $subrs = (ref $self)->new($rsrc, $attrs);
1946 if (@$idcols == 1) {
1947 $cond = { $idcols->[0] => { -in => $subrs->as_query } };
1949 elsif ($storage->_use_multicolumn_in) {
1950 # no syntax for calling this properly yet
1951 # !!! EXPERIMENTAL API !!! WILL CHANGE !!!
1952 $cond = $storage->sql_maker->_where_op_multicolumn_in (
1953 $idcols, # how do I convey a list of idents...? can binds reside on lhs?
1958 # if all else fails - get all primary keys and operate over a ORed set
1959 # wrap in a transaction for consistency
1960 # this is where the group_by/multiplication starts to matter
1964 # we do not need to check pre-multipliers, since if the premulti is there, its
1965 # parent (who is multi) will be there too
1966 keys %{ $join_classifications->{multiplying} || {} }
1968 # make sure if there is a supplied group_by it matches the columns compiled above
1969 # perfectly. Anything else can not be sanely executed on most databases so croak
1970 # right then and there
1971 if ($existing_group_by) {
1972 my @current_group_by = map
1973 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1978 join ("\x00", sort @current_group_by)
1980 join ("\x00", sort @{$attrs->{columns}} )
1982 $self->throw_exception (
1983 "You have just attempted a $op operation on a resultset which does group_by"
1984 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1985 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1986 . ' kind of queries. Please retry the operation with a modified group_by or'
1987 . ' without using one at all.'
1992 $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
1995 $guard = $storage->txn_scope_guard;
1997 for my $row ($subrs->cursor->all) {
1999 { $idcols->[$_] => $row->[$_] }
2006 my $res = $cond ? $storage->$op (
2008 $op eq 'update' ? $values : (),
2012 $guard->commit if $guard;
2021 =item Arguments: \%values
2023 =item Return Value: $underlying_storage_rv
2027 Sets the specified columns in the resultset to the supplied values in a
2028 single query. Note that this will not run any accessor/set_column/update
2029 triggers, nor will it update any result object instances derived from this
2030 resultset (this includes the contents of the L<resultset cache|/set_cache>
2031 if any). See L</update_all> if you need to execute any on-update
2032 triggers or cascades defined either by you or a
2033 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2035 The return value is a pass through of what the underlying
2036 storage backend returned, and may vary. See L<DBI/execute> for the most
2041 Note that L</update> does not process/deflate any of the values passed in.
2042 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
2043 ensure manually that any value passed to this method will stringify to
2044 something the RDBMS knows how to deal with. A notable example is the
2045 handling of L<DateTime> objects, for more info see:
2046 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
2051 my ($self, $values) = @_;
2052 $self->throw_exception('Values for update must be a hash')
2053 unless ref $values eq 'HASH';
2055 return $self->_rs_update_delete ('update', $values);
2062 =item Arguments: \%values
2064 =item Return Value: 1
2068 Fetches all objects and updates them one at a time via
2069 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
2070 triggers, while L</update> will not.
2075 my ($self, $values) = @_;
2076 $self->throw_exception('Values for update_all must be a hash')
2077 unless ref $values eq 'HASH';
2079 my $guard = $self->result_source->schema->txn_scope_guard;
2080 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
2089 =item Arguments: none
2091 =item Return Value: $underlying_storage_rv
2095 Deletes the rows matching this resultset in a single query. Note that this
2096 will not run any delete triggers, nor will it alter the
2097 L<in_storage|DBIx::Class::Row/in_storage> status of any result object instances
2098 derived from this resultset (this includes the contents of the
2099 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
2100 execute any on-delete triggers or cascades defined either by you or a
2101 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2103 The return value is a pass through of what the underlying storage backend
2104 returned, and may vary. See L<DBI/execute> for the most common case.
2110 $self->throw_exception('delete does not accept any arguments')
2113 return $self->_rs_update_delete ('delete');
2120 =item Arguments: none
2122 =item Return Value: 1
2126 Fetches all objects and deletes them one at a time via
2127 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2128 triggers, while L</delete> will not.
2134 $self->throw_exception('delete_all does not accept any arguments')
2137 my $guard = $self->result_source->schema->txn_scope_guard;
2138 $_->delete for $self->all;
2147 =item Arguments: [ \@column_list, \@row_values+ ] | [ \%col_data+ ]
2149 =item Return Value: L<\@result_objects|DBIx::Class::Manual::ResultClass> (scalar context) | L<@result_objects|DBIx::Class::Manual::ResultClass> (list context)
2153 Accepts either an arrayref of hashrefs or alternatively an arrayref of
2160 The context of this method call has an important effect on what is
2161 submitted to storage. In void context data is fed directly to fastpath
2162 insertion routines provided by the underlying storage (most often
2163 L<DBI/execute_for_fetch>), bypassing the L<new|DBIx::Class::Row/new> and
2164 L<insert|DBIx::Class::Row/insert> calls on the
2165 L<Result|DBIx::Class::Manual::ResultClass> class, including any
2166 augmentation of these methods provided by components. For example if you
2167 are using something like L<DBIx::Class::UUIDColumns> to create primary
2168 keys for you, you will find that your PKs are empty. In this case you
2169 will have to explicitly force scalar or list context in order to create
2174 In non-void (scalar or list) context, this method is simply a wrapper
2175 for L</create>. Depending on list or scalar context either a list of
2176 L<Result|DBIx::Class::Manual::ResultClass> objects or an arrayref
2177 containing these objects is returned.
2179 When supplying data in "arrayref of arrayrefs" invocation style, the
2180 first element should be a list of column names and each subsequent
2181 element should be a data value in the earlier specified column order.
2184 $schema->resultset("Artist")->populate([
2185 [ qw( artistid name ) ],
2186 [ 100, 'A Formally Unknown Singer' ],
2187 [ 101, 'A singer that jumped the shark two albums ago' ],
2188 [ 102, 'An actually cool singer' ],
2191 For the arrayref of hashrefs style each hashref should be a structure
2192 suitable for passing to L</create>. Multi-create is also permitted with
2195 $schema->resultset("Artist")->populate([
2196 { artistid => 4, name => 'Manufactured Crap', cds => [
2197 { title => 'My First CD', year => 2006 },
2198 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2201 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2202 { title => 'My parents sold me to a record company', year => 2005 },
2203 { title => 'Why Am I So Ugly?', year => 2006 },
2204 { title => 'I Got Surgery and am now Popular', year => 2007 }
2209 If you attempt a void-context multi-create as in the example above (each
2210 Artist also has the related list of CDs), and B<do not> supply the
2211 necessary autoinc foreign key information, this method will proxy to the
2212 less efficient L</create>, and then throw the Result objects away. In this
2213 case there are obviously no benefits to using this method over L</create>.
2220 # this is naive and just a quick check
2221 # the types will need to be checked more thoroughly when the
2222 # multi-source populate gets added
2224 ref $_[0] eq 'ARRAY'
2226 ( @{$_[0]} or return )
2228 ( ref $_[0][0] eq 'HASH' or ref $_[0][0] eq 'ARRAY' )
2231 ) or $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2233 # FIXME - no cref handling
2234 # At this point assume either hashes or arrays
2236 if(defined wantarray) {
2237 my (@results, $guard);
2239 if (ref $data->[0] eq 'ARRAY') {
2240 # column names only, nothing to do
2241 return if @$data == 1;
2243 $guard = $self->result_source->schema->storage->txn_scope_guard
2247 { my $vals = $_; $self->new_result({ map { $data->[0][$_] => $vals->[$_] } 0..$#{$data->[0]} })->insert }
2248 @{$data}[1 .. $#$data]
2253 $guard = $self->result_source->schema->storage->txn_scope_guard
2256 @results = map { $self->new_result($_)->insert } @$data;
2259 $guard->commit if $guard;
2260 return wantarray ? @results : \@results;
2263 # we have to deal with *possibly incomplete* related data
2264 # this means we have to walk the data structure twice
2265 # whether we want this or not
2266 # jnap, I hate you ;)
2267 my $rsrc = $self->result_source;
2268 my $rel_info = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2270 my ($colinfo, $colnames, $slices_with_rels);
2274 for my $i (0 .. $#$data) {
2276 my $current_slice_seen_rel_infos;
2278 ### Determine/Supplement collists
2279 ### BEWARE - This is a hot piece of code, a lot of weird idioms were used
2280 if( ref $data->[$i] eq 'ARRAY' ) {
2282 # positional(!) explicit column list
2284 # column names only, nothing to do
2285 return if @$data == 1;
2287 $colinfo->{$data->[0][$_]} = { pos => $_, name => $data->[0][$_] } and push @$colnames, $data->[0][$_]
2288 for 0 .. $#{$data->[0]};
2295 for (values %$colinfo) {
2296 if ($_->{is_rel} ||= (
2297 $rel_info->{$_->{name}}
2300 ref $data->[$i][$_->{pos}] eq 'ARRAY'
2302 ref $data->[$i][$_->{pos}] eq 'HASH'
2304 ( defined blessed $data->[$i][$_->{pos}] and $data->[$i][$_->{pos}]->isa('DBIx::Class::Row') )
2310 # moar sanity check... sigh
2311 for ( ref $data->[$i][$_->{pos}] eq 'ARRAY' ? @{$data->[$i][$_->{pos}]} : $data->[$i][$_->{pos}] ) {
2312 if ( defined blessed $_ and $_->isa('DBIx::Class::Row' ) ) {
2313 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2314 return my $throwaway = $self->populate(@_);
2318 push @$current_slice_seen_rel_infos, $rel_info->{$_->{name}};
2323 if ($current_slice_seen_rel_infos) {
2324 push @$slices_with_rels, { map { $colnames->[$_] => $data->[$i][$_] } 0 .. $#$colnames };
2326 # this is needed further down to decide whether or not to fallback to create()
2327 $colinfo->{$colnames->[$_]}{seen_null} ||= ! defined $data->[$i][$_]
2328 for 0 .. $#$colnames;
2331 elsif( ref $data->[$i] eq 'HASH' ) {
2333 for ( sort keys %{$data->[$i]} ) {
2335 $colinfo->{$_} ||= do {
2337 $self->throw_exception("Column '$_' must be present in supplied explicit column list")
2338 if $data_start; # it will be 0 on AoH, 1 on AoA
2340 push @$colnames, $_;
2343 { pos => $#$colnames, name => $_ }
2346 if ($colinfo->{$_}{is_rel} ||= (
2350 ref $data->[$i]{$_} eq 'ARRAY'
2352 ref $data->[$i]{$_} eq 'HASH'
2354 ( defined blessed $data->[$i]{$_} and $data->[$i]{$_}->isa('DBIx::Class::Row') )
2360 # moar sanity check... sigh
2361 for ( ref $data->[$i]{$_} eq 'ARRAY' ? @{$data->[$i]{$_}} : $data->[$i]{$_} ) {
2362 if ( defined blessed $_ and $_->isa('DBIx::Class::Row' ) ) {
2363 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2364 return my $throwaway = $self->populate(@_);
2368 push @$current_slice_seen_rel_infos, $rel_info->{$_};
2372 if ($current_slice_seen_rel_infos) {
2373 push @$slices_with_rels, $data->[$i];
2375 # this is needed further down to decide whether or not to fallback to create()
2376 $colinfo->{$_}{seen_null} ||= ! defined $data->[$i]{$_}
2377 for keys %{$data->[$i]};
2381 $self->throw_exception('Unexpected populate() data structure member type: ' . ref $data->[$i] );
2385 { $_->{attrs}{is_depends_on} }
2386 @{ $current_slice_seen_rel_infos || [] }
2388 carp_unique("Fast-path populate() of belongs_to relationship data is not possible - falling back to regular create()");
2389 return my $throwaway = $self->populate(@_);
2393 if( $slices_with_rels ) {
2395 # need to exclude the rel "columns"
2396 $colnames = [ grep { ! $colinfo->{$_}{is_rel} } @$colnames ];
2398 # extra sanity check - ensure the main source is in fact identifiable
2399 # the localizing of nullability is insane, but oh well... the use-case is legit
2400 my $ci = $rsrc->columns_info($colnames);
2402 $ci->{$_} = { %{$ci->{$_}}, is_nullable => 0 }
2403 for grep { ! $colinfo->{$_}{seen_null} } keys %$ci;
2405 unless( $rsrc->_identifying_column_set($ci) ) {
2406 carp_unique("Fast-path populate() of non-uniquely identifiable rows with related data is not possible - falling back to regular create()");
2407 return my $throwaway = $self->populate(@_);
2411 ### inherit the data locked in the conditions of the resultset
2412 my ($rs_data) = $self->_merge_with_rscond({});
2413 delete @{$rs_data}{@$colnames}; # passed-in stuff takes precedence
2415 # if anything left - decompose rs_data
2417 if (keys %$rs_data) {
2418 push @$rs_data_vals, $rs_data->{$_}
2419 for sort keys %$rs_data;
2424 $guard = $rsrc->schema->storage->txn_scope_guard
2425 if $slices_with_rels;
2427 ### main source data
2428 # FIXME - need to switch entirely to a coderef-based thing,
2429 # so that large sets aren't copied several times... I think
2430 $rsrc->storage->_insert_bulk(
2432 [ @$colnames, sort keys %$rs_data ],
2434 ref $data->[$_] eq 'ARRAY'
2436 $slices_with_rels ? [ @{$data->[$_]}[0..$#$colnames], @{$rs_data_vals||[]} ] # the collist changed
2437 : $rs_data_vals ? [ @{$data->[$_]}, @$rs_data_vals ]
2440 : [ @{$data->[$_]}{@$colnames}, @{$rs_data_vals||[]} ]
2441 } $data_start .. $#$data ],
2444 ### do the children relationships
2445 if ( $slices_with_rels ) {
2446 my @rels = grep { $colinfo->{$_}{is_rel} } keys %$colinfo
2447 or die 'wtf... please report a bug with DBIC_TRACE=1 output (stacktrace)';
2449 for my $sl (@$slices_with_rels) {
2451 my ($main_proto, $main_proto_rs);
2452 for my $rel (@rels) {
2453 next unless defined $sl->{$rel};
2457 (map { $_ => $sl->{$_} } @$colnames),
2460 unless (defined $colinfo->{$rel}{rs}) {
2462 $colinfo->{$rel}{rs} = $rsrc->related_source($rel)->resultset;
2464 $colinfo->{$rel}{fk_map} = { reverse %{ $rsrc->_resolve_relationship_condition(
2466 self_alias => "\xFE", # irrelevant
2467 foreign_alias => "\xFF", # irrelevant
2468 )->{identity_map} || {} } };
2472 $colinfo->{$rel}{rs}->search({ map # only so that we inherit them values properly, no actual search
2475 ( $main_proto_rs ||= $rsrc->resultset->search($main_proto) )
2476 ->get_column( $colinfo->{$rel}{fk_map}{$_} )
2480 keys %{$colinfo->{$rel}{fk_map}}
2481 })->populate( ref $sl->{$rel} eq 'ARRAY' ? $sl->{$rel} : [ $sl->{$rel} ] );
2488 $guard->commit if $guard;
2495 =item Arguments: none
2497 =item Return Value: L<$pager|Data::Page>
2501 Returns a L<Data::Page> object for the current resultset. Only makes
2502 sense for queries with a C<page> attribute.
2504 To get the full count of entries for a paged resultset, call
2505 C<total_entries> on the L<Data::Page> object.
2512 return $self->{pager} if $self->{pager};
2514 my $attrs = $self->{attrs};
2515 if (!defined $attrs->{page}) {
2516 $self->throw_exception("Can't create pager for non-paged rs");
2518 elsif ($attrs->{page} <= 0) {
2519 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2521 $attrs->{rows} ||= 10;
2523 # throw away the paging flags and re-run the count (possibly
2524 # with a subselect) to get the real total count
2525 my $count_attrs = { %$attrs };
2526 delete @{$count_attrs}{qw/rows offset page pager/};
2528 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2530 require DBIx::Class::ResultSet::Pager;
2531 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2532 sub { $total_rs->count }, #lazy-get the total
2534 $self->{attrs}{page},
2542 =item Arguments: $page_number
2544 =item Return Value: L<$resultset|/search>
2548 Returns a resultset for the $page_number page of the resultset on which page
2549 is called, where each page contains a number of rows equal to the 'rows'
2550 attribute set on the resultset (10 by default).
2555 my ($self, $page) = @_;
2556 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2563 =item Arguments: \%col_data
2565 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2569 Creates a new result object in the resultset's result class and returns
2570 it. The row is not inserted into the database at this point, call
2571 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2572 will tell you whether the result object has been inserted or not.
2574 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2579 my ($self, $values) = @_;
2581 $self->throw_exception( "new_result takes only one argument - a hashref of values" )
2584 $self->throw_exception( "Result object instantiation requires a hashref as argument" )
2585 unless (ref $values eq 'HASH');
2587 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2589 my $new = $self->result_class->new({
2591 ( @$cols_from_relations
2592 ? (-cols_from_relations => $cols_from_relations)
2595 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2599 reftype($new) eq 'HASH'
2605 carp_unique (sprintf (
2606 "%s->new returned a blessed empty hashref - a strong indicator something is wrong with its inheritance chain",
2607 $self->result_class,
2614 # _merge_with_rscond
2616 # Takes a simple hash of K/V data and returns its copy merged with the
2617 # condition already present on the resultset. Additionally returns an
2618 # arrayref of value/condition names, which were inferred from related
2619 # objects (this is needed for in-memory related objects)
2620 sub _merge_with_rscond {
2621 my ($self, $data) = @_;
2623 my ($implied_data, @cols_from_relations);
2625 my $alias = $self->{attrs}{alias};
2627 if (! defined $self->{cond}) {
2628 # just massage $data below
2630 elsif ($self->{cond} eq UNRESOLVABLE_CONDITION) {
2631 $implied_data = $self->{attrs}{related_objects}; # nothing might have been inserted yet
2632 @cols_from_relations = keys %{ $implied_data || {} };
2635 my $eqs = $self->result_source->schema->storage->_extract_fixed_condition_columns($self->{cond}, 'consider_nulls');
2636 $implied_data = { map {
2637 ( ($eqs->{$_}||'') eq UNRESOLVABLE_CONDITION ) ? () : ( $_ => $eqs->{$_} )
2643 { %{ $self->_remove_alias($_, $alias) } }
2644 # precedence must be given to passed values over values inherited from
2645 # the cond, so the order here is important.
2646 ( $implied_data||(), $data)
2648 \@cols_from_relations
2652 # _has_resolved_attr
2654 # determines if the resultset defines at least one
2655 # of the attributes supplied
2657 # used to determine if a subquery is necessary
2659 # supports some virtual attributes:
2661 # This will scan for any joins being present on the resultset.
2662 # It is not a mere key-search but a deep inspection of {from}
2665 sub _has_resolved_attr {
2666 my ($self, @attr_names) = @_;
2668 my $attrs = $self->_resolved_attrs;
2672 for my $n (@attr_names) {
2673 if (grep { $n eq $_ } (qw/-join/) ) {
2674 $extra_checks{$n}++;
2678 my $attr = $attrs->{$n};
2680 next if not defined $attr;
2682 if (ref $attr eq 'HASH') {
2683 return 1 if keys %$attr;
2685 elsif (ref $attr eq 'ARRAY') {
2693 # a resolved join is expressed as a multi-level from
2695 $extra_checks{-join}
2697 ref $attrs->{from} eq 'ARRAY'
2699 @{$attrs->{from}} > 1
2707 # Remove the specified alias from the specified query hash. A copy is made so
2708 # the original query is not modified.
2711 my ($self, $query, $alias) = @_;
2713 my %orig = %{ $query || {} };
2716 foreach my $key (keys %orig) {
2718 $unaliased{$key} = $orig{$key};
2721 $unaliased{$1} = $orig{$key}
2722 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2732 =item Arguments: none
2734 =item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
2738 Returns the SQL query and bind vars associated with the invocant.
2740 This is generally used as the RHS for a subquery.
2747 my $attrs = { %{ $self->_resolved_attrs } };
2749 my $aq = $self->result_source->storage->_select_args_to_query (
2750 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
2760 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2762 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2766 my $artist = $schema->resultset('Artist')->find_or_new(
2767 { artist => 'fred' }, { key => 'artists' });
2769 $cd->cd_to_producer->find_or_new({ producer => $producer },
2770 { key => 'primary' });
2772 Find an existing record from this resultset using L</find>. if none exists,
2773 instantiate a new result object and return it. The object will not be saved
2774 into your storage until you call L<DBIx::Class::Row/insert> on it.
2776 You most likely want this method when looking for existing rows using a unique
2777 constraint that is not the primary key, or looking for related rows.
2779 If you want objects to be saved immediately, use L</find_or_create> instead.
2781 B<Note>: Make sure to read the documentation of L</find> and understand the
2782 significance of the C<key> attribute, as its lack may skew your search, and
2783 subsequently result in spurious new objects.
2785 B<Note>: Take care when using C<find_or_new> with a table having
2786 columns with default values that you intend to be automatically
2787 supplied by the database (e.g. an auto_increment primary key column).
2788 In normal usage, the value of such columns should NOT be included at
2789 all in the call to C<find_or_new>, even when set to C<undef>.
2795 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2796 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2797 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2800 return $self->new_result($hash);
2807 =item Arguments: \%col_data
2809 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2813 Attempt to create a single new row or a row with multiple related rows
2814 in the table represented by the resultset (and related tables). This
2815 will not check for duplicate rows before inserting, use
2816 L</find_or_create> to do that.
2818 To create one row for this resultset, pass a hashref of key/value
2819 pairs representing the columns of the table and the values you wish to
2820 store. If the appropriate relationships are set up, foreign key fields
2821 can also be passed an object representing the foreign row, and the
2822 value will be set to its primary key.
2824 To create related objects, pass a hashref of related-object column values
2825 B<keyed on the relationship name>. If the relationship is of type C<multi>
2826 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2827 The process will correctly identify columns holding foreign keys, and will
2828 transparently populate them from the keys of the corresponding relation.
2829 This can be applied recursively, and will work correctly for a structure
2830 with an arbitrary depth and width, as long as the relationships actually
2831 exists and the correct column data has been supplied.
2833 Instead of hashrefs of plain related data (key/value pairs), you may
2834 also pass new or inserted objects. New objects (not inserted yet, see
2835 L</new_result>), will be inserted into their appropriate tables.
2837 Effectively a shortcut for C<< ->new_result(\%col_data)->insert >>.
2839 Example of creating a new row.
2841 $person_rs->create({
2842 name=>"Some Person",
2843 email=>"somebody@someplace.com"
2846 Example of creating a new row and also creating rows in a related C<has_many>
2847 or C<has_one> resultset. Note Arrayref.
2850 { artistid => 4, name => 'Manufactured Crap', cds => [
2851 { title => 'My First CD', year => 2006 },
2852 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2857 Example of creating a new row and also creating a row in a related
2858 C<belongs_to> resultset. Note Hashref.
2861 title=>"Music for Silly Walks",
2864 name=>"Silly Musician",
2872 When subclassing ResultSet never attempt to override this method. Since
2873 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2874 lot of the internals simply never call it, so your override will be
2875 bypassed more often than not. Override either L<DBIx::Class::Row/new>
2876 or L<DBIx::Class::Row/insert> depending on how early in the
2877 L</create> process you need to intervene. See also warning pertaining to
2885 #my ($self, $col_data) = @_;
2886 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
2887 return shift->new_result(shift)->insert;
2890 =head2 find_or_create
2894 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2896 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2900 $cd->cd_to_producer->find_or_create({ producer => $producer },
2901 { key => 'primary' });
2903 Tries to find a record based on its primary key or unique constraints; if none
2904 is found, creates one and returns that instead.
2906 my $cd = $schema->resultset('CD')->find_or_create({
2908 artist => 'Massive Attack',
2909 title => 'Mezzanine',
2913 Also takes an optional C<key> attribute, to search by a specific key or unique
2914 constraint. For example:
2916 my $cd = $schema->resultset('CD')->find_or_create(
2918 artist => 'Massive Attack',
2919 title => 'Mezzanine',
2921 { key => 'cd_artist_title' }
2924 B<Note>: Make sure to read the documentation of L</find> and understand the
2925 significance of the C<key> attribute, as its lack may skew your search, and
2926 subsequently result in spurious row creation.
2928 B<Note>: Because find_or_create() reads from the database and then
2929 possibly inserts based on the result, this method is subject to a race
2930 condition. Another process could create a record in the table after
2931 the find has completed and before the create has started. To avoid
2932 this problem, use find_or_create() inside a transaction.
2934 B<Note>: Take care when using C<find_or_create> with a table having
2935 columns with default values that you intend to be automatically
2936 supplied by the database (e.g. an auto_increment primary key column).
2937 In normal usage, the value of such columns should NOT be included at
2938 all in the call to C<find_or_create>, even when set to C<undef>.
2940 See also L</find> and L</update_or_create>. For information on how to declare
2941 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2943 If you need to know if an existing row was found or a new one created use
2944 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2945 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2948 my $cd = $schema->resultset('CD')->find_or_new({
2950 artist => 'Massive Attack',
2951 title => 'Mezzanine',
2955 if( !$cd->in_storage ) {
2962 sub find_or_create {
2964 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2965 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2966 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2969 return $self->new_result($hash)->insert;
2972 =head2 update_or_create
2976 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2978 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2982 $resultset->update_or_create({ col => $val, ... });
2984 Like L</find_or_create>, but if a row is found it is immediately updated via
2985 C<< $found_row->update (\%col_data) >>.
2988 Takes an optional C<key> attribute to search on a specific unique constraint.
2991 # In your application
2992 my $cd = $schema->resultset('CD')->update_or_create(
2994 artist => 'Massive Attack',
2995 title => 'Mezzanine',
2998 { key => 'cd_artist_title' }
3001 $cd->cd_to_producer->update_or_create({
3002 producer => $producer,
3008 B<Note>: Make sure to read the documentation of L</find> and understand the
3009 significance of the C<key> attribute, as its lack may skew your search, and
3010 subsequently result in spurious row creation.
3012 B<Note>: Take care when using C<update_or_create> with a table having
3013 columns with default values that you intend to be automatically
3014 supplied by the database (e.g. an auto_increment primary key column).
3015 In normal usage, the value of such columns should NOT be included at
3016 all in the call to C<update_or_create>, even when set to C<undef>.
3018 See also L</find> and L</find_or_create>. For information on how to declare
3019 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
3021 If you need to know if an existing row was updated or a new one created use
3022 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
3023 to call L<DBIx::Class::Row/insert> to save the newly created row to the
3028 sub update_or_create {
3030 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
3031 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3033 my $row = $self->find($cond, $attrs);
3035 $row->update($cond);
3039 return $self->new_result($cond)->insert;
3042 =head2 update_or_new
3046 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
3048 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
3052 $resultset->update_or_new({ col => $val, ... });
3054 Like L</find_or_new> but if a row is found it is immediately updated via
3055 C<< $found_row->update (\%col_data) >>.
3059 # In your application
3060 my $cd = $schema->resultset('CD')->update_or_new(
3062 artist => 'Massive Attack',
3063 title => 'Mezzanine',
3066 { key => 'cd_artist_title' }
3069 if ($cd->in_storage) {
3070 # the cd was updated
3073 # the cd is not yet in the database, let's insert it
3077 B<Note>: Make sure to read the documentation of L</find> and understand the
3078 significance of the C<key> attribute, as its lack may skew your search, and
3079 subsequently result in spurious new objects.
3081 B<Note>: Take care when using C<update_or_new> with a table having
3082 columns with default values that you intend to be automatically
3083 supplied by the database (e.g. an auto_increment primary key column).
3084 In normal usage, the value of such columns should NOT be included at
3085 all in the call to C<update_or_new>, even when set to C<undef>.
3087 See also L</find>, L</find_or_create> and L</find_or_new>.
3093 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
3094 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3096 my $row = $self->find( $cond, $attrs );
3097 if ( defined $row ) {
3098 $row->update($cond);
3102 return $self->new_result($cond);
3109 =item Arguments: none
3111 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass> | undef
3115 Gets the contents of the cache for the resultset, if the cache is set.
3117 The cache is populated either by using the L</prefetch> attribute to
3118 L</search> or by calling L</set_cache>.
3130 =item Arguments: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3132 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3136 Sets the contents of the cache for the resultset. Expects an arrayref
3137 of objects of the same class as those produced by the resultset. Note that
3138 if the cache is set, the resultset will return the cached objects rather
3139 than re-querying the database even if the cache attr is not set.
3141 The contents of the cache can also be populated by using the
3142 L</prefetch> attribute to L</search>.
3147 my ( $self, $data ) = @_;
3148 $self->throw_exception("set_cache requires an arrayref")
3149 if defined($data) && (ref $data ne 'ARRAY');
3150 $self->{all_cache} = $data;
3157 =item Arguments: none
3159 =item Return Value: undef
3163 Clears the cache for the resultset.
3168 shift->set_cache(undef);
3175 =item Arguments: none
3177 =item Return Value: true, if the resultset has been paginated
3185 return !!$self->{attrs}{page};
3192 =item Arguments: none
3194 =item Return Value: true, if the resultset has been ordered with C<order_by>.
3202 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
3205 =head2 related_resultset
3209 =item Arguments: $rel_name
3211 =item Return Value: L<$resultset|/search>
3215 Returns a related resultset for the supplied relationship name.
3217 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
3221 sub related_resultset {
3222 $_[0]->throw_exception(
3223 'Extra arguments to $rs->related_resultset() were always quietly '
3224 . 'discarded without consideration, you need to switch to '
3225 . '...->related_resultset( $relname )->search_rs( $search, $args ) instead.'
3228 return $_[0]->{related_resultsets}{$_[1]}
3229 if defined $_[0]->{related_resultsets}{$_[1]};
3231 my ($self, $rel) = @_;
3233 return $self->{related_resultsets}{$rel} = do {
3234 my $rsrc = $self->result_source;
3235 my $rel_info = $rsrc->relationship_info($rel);
3237 $self->throw_exception(
3238 "search_related: result source '" . $rsrc->source_name .
3239 "' has no such relationship $rel")
3242 my $attrs = $self->_chain_relationship($rel);
3244 my $storage = $rsrc->schema->storage;
3246 # Previously this atribute was deleted (instead of being set as it is now)
3247 # Doing so seems to be harmless in all available test permutations
3248 # See also 01d59a6a6 and mst's comment below
3250 $attrs->{alias} = $storage->relname_to_table_alias(
3252 $attrs->{seen_join}{$rel}
3255 # since this is search_related, and we already slid the select window inwards
3256 # (the select/as attrs were deleted in the beginning), we need to flip all
3257 # left joins to inner, so we get the expected results
3258 # read the comment on top of the actual function to see what this does
3259 $attrs->{from} = $storage->_inner_join_to_node( $attrs->{from}, $attrs->{alias} );
3261 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3262 delete $attrs->{result_class};
3266 # The reason we do this now instead of passing the alias to the
3267 # search_rs below is that if you wrap/overload resultset on the
3268 # source you need to know what alias it's -going- to have for things
3269 # to work sanely (e.g. RestrictWithObject wants to be able to add
3270 # extra query restrictions, and these may need to be $alias.)
3271 # -- mst ~ 2007 (01d59a6a6)
3273 # FIXME - this seems to be no longer neccessary (perhaps due to the
3274 # advances in relcond resolution. Testing DBIC::S::RWO and its only
3275 # dependent (as of Jun 2015 ) does not yield any difference with or
3276 # without this line. Nevertheless keep it as is for now, to minimize
3277 # churn, there is enough potential for breakage in 0.0829xx as it is
3278 # -- ribasushi Jun 2015
3280 my $rel_source = $rsrc->related_source($rel);
3281 local $rel_source->resultset_attributes->{alias} = $attrs->{alias};
3283 $rel_source->resultset->search_rs( undef, $attrs );
3286 if (my $cache = $self->get_cache) {
3287 my @related_cache = map
3288 { $_->related_resultset($rel)->get_cache || () }
3292 $new->set_cache([ map @$_, @related_cache ]) if @related_cache == @$cache;
3299 =head2 current_source_alias
3303 =item Arguments: none
3305 =item Return Value: $source_alias
3309 Returns the current table alias for the result source this resultset is built
3310 on, that will be used in the SQL query. Usually it is C<me>.
3312 Currently the source alias that refers to the result set returned by a
3313 L</search>/L</find> family method depends on how you got to the resultset: it's
3314 C<me> by default, but eg. L</search_related> aliases it to the related result
3315 source name (and keeps C<me> referring to the original result set). The long
3316 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3317 (and make this method unnecessary).
3319 Thus it's currently necessary to use this method in predefined queries (see
3320 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3321 source alias of the current result set:
3323 # in a result set class
3325 my ($self, $user) = @_;
3327 my $me = $self->current_source_alias;
3329 return $self->search({
3330 "$me.modified" => $user->id,
3334 The alias of L<newly created resultsets|/search> can be altered by the
3335 L<alias attribute|/alias>.
3339 sub current_source_alias {
3340 return (shift->{attrs} || {})->{alias} || 'me';
3343 =head2 as_subselect_rs
3347 =item Arguments: none
3349 =item Return Value: L<$resultset|/search>
3353 Act as a barrier to SQL symbols. The resultset provided will be made into a
3354 "virtual view" by including it as a subquery within the from clause. From this
3355 point on, any joined tables are inaccessible to ->search on the resultset (as if
3356 it were simply where-filtered without joins). For example:
3358 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3360 # 'x' now pollutes the query namespace
3362 # So the following works as expected
3363 my $ok_rs = $rs->search({'x.other' => 1});
3365 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3366 # def) we look for one row with contradictory terms and join in another table
3367 # (aliased 'x_2') which we never use
3368 my $broken_rs = $rs->search({'x.name' => 'def'});
3370 my $rs2 = $rs->as_subselect_rs;
3372 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3373 my $not_joined_rs = $rs2->search({'x.other' => 1});
3375 # works as expected: finds a 'table' row related to two x rows (abc and def)
3376 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3378 Another example of when one might use this would be to select a subset of
3379 columns in a group by clause:
3381 my $rs = $schema->resultset('Bar')->search(undef, {
3382 group_by => [qw{ id foo_id baz_id }],
3383 })->as_subselect_rs->search(undef, {
3384 columns => [qw{ id foo_id }]
3387 In the above example normally columns would have to be equal to the group by,
3388 but because we isolated the group by into a subselect the above works.
3392 sub as_subselect_rs {
3395 my $attrs = $self->_resolved_attrs;
3397 my $fresh_rs = (ref $self)->new (
3398 $self->result_source
3401 # these pieces will be locked in the subquery
3402 delete $fresh_rs->{cond};
3403 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3405 return $fresh_rs->search( {}, {
3407 $attrs->{alias} => $self->as_query,
3408 -alias => $attrs->{alias},
3409 -rsrc => $self->result_source,
3411 alias => $attrs->{alias},
3415 # This code is called by search_related, and makes sure there
3416 # is clear separation between the joins before, during, and
3417 # after the relationship. This information is needed later
3418 # in order to properly resolve prefetch aliases (any alias
3419 # with a relation_chain_depth less than the depth of the
3420 # current prefetch is not considered)
3422 # The increments happen twice per join. An even number means a
3423 # relationship specified via a search_related, whereas an odd
3424 # number indicates a join/prefetch added via attributes
3426 # Also this code will wrap the current resultset (the one we
3427 # chain to) in a subselect IFF it contains limiting attributes
3428 sub _chain_relationship {
3429 my ($self, $rel) = @_;
3430 my $source = $self->result_source;
3431 my $attrs = { %{$self->{attrs}||{}} };
3433 # we need to take the prefetch the attrs into account before we
3434 # ->_resolve_join as otherwise they get lost - captainL
3435 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3437 delete @{$attrs}{qw/join prefetch collapse group_by distinct _grouped_by_distinct select as columns +select +as +columns/};
3439 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3442 my @force_subq_attrs = qw/offset rows group_by having/;
3445 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3447 $self->_has_resolved_attr (@force_subq_attrs)
3449 # Nuke the prefetch (if any) before the new $rs attrs
3450 # are resolved (prefetch is useless - we are wrapping
3451 # a subquery anyway).
3452 my $rs_copy = $self->search;
3453 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3454 $rs_copy->{attrs}{join},
3455 delete $rs_copy->{attrs}{prefetch},
3460 -alias => $attrs->{alias},
3461 $attrs->{alias} => $rs_copy->as_query,
3463 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3464 $seen->{-relation_chain_depth} = 0;
3466 elsif ($attrs->{from}) { #shallow copy suffices
3467 $from = [ @{$attrs->{from}} ];
3472 -alias => $attrs->{alias},
3473 $attrs->{alias} => $source->from,
3477 my $jpath = ($seen->{-relation_chain_depth})
3478 ? $from->[-1][0]{-join_path}
3481 my @requested_joins = $source->_resolve_join(
3488 push @$from, @requested_joins;
3490 $seen->{-relation_chain_depth}++;
3492 # if $self already had a join/prefetch specified on it, the requested
3493 # $rel might very well be already included. What we do in this case
3494 # is effectively a no-op (except that we bump up the chain_depth on
3495 # the join in question so we could tell it *is* the search_related)
3498 # we consider the last one thus reverse
3499 for my $j (reverse @requested_joins) {
3500 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3501 if ($rel eq $last_j) {
3502 $j->[0]{-relation_chain_depth}++;
3508 unless ($already_joined) {
3509 push @$from, $source->_resolve_join(
3517 $seen->{-relation_chain_depth}++;
3519 return {%$attrs, from => $from, seen_join => $seen};
3522 sub _resolved_attrs {
3524 return $self->{_attrs} if $self->{_attrs};
3526 my $attrs = { %{ $self->{attrs} || {} } };
3527 my $source = $attrs->{result_source} = $self->result_source;
3528 my $alias = $attrs->{alias};
3530 $self->throw_exception("Specifying distinct => 1 in conjunction with collapse => 1 is unsupported")
3531 if $attrs->{collapse} and $attrs->{distinct};
3534 # Sanity check the paging attributes
3535 # SQLMaker does it too, but in case of a software_limit we'll never get there
3536 if (defined $attrs->{offset}) {
3537 $self->throw_exception('A supplied offset attribute must be a non-negative integer')
3538 if ( $attrs->{offset} =~ /[^0-9]/ or $attrs->{offset} < 0 );
3540 if (defined $attrs->{rows}) {
3541 $self->throw_exception("The rows attribute must be a positive integer if present")
3542 if ( $attrs->{rows} =~ /[^0-9]/ or $attrs->{rows} <= 0 );
3546 # default selection list
3547 $attrs->{columns} = [ $source->columns ]
3548 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3550 # merge selectors together
3551 for (qw/columns select as/) {
3552 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3553 if $attrs->{$_} or $attrs->{"+$_"};
3556 # disassemble columns
3558 if (my $cols = delete $attrs->{columns}) {
3559 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3560 if (ref $c eq 'HASH') {
3561 for my $as (sort keys %$c) {
3562 push @sel, $c->{$as};
3573 # when trying to weed off duplicates later do not go past this point -
3574 # everything added from here on is unbalanced "anyone's guess" stuff
3575 my $dedup_stop_idx = $#as;
3577 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3579 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3580 if $attrs->{select};
3582 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3583 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3585 # disqualify all $alias.col as-bits (inflate-map mandated)
3586 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3588 # de-duplicate the result (remove *identical* select/as pairs)
3589 # and also die on duplicate {as} pointing to different {select}s
3590 # not using a c-style for as the condition is prone to shrinkage
3593 while ($i <= $dedup_stop_idx) {
3594 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3599 elsif ($seen->{$as[$i]}++) {
3600 $self->throw_exception(
3601 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3609 $attrs->{select} = \@sel;
3610 $attrs->{as} = \@as;
3612 $attrs->{from} ||= [{
3614 -alias => $self->{attrs}{alias},
3615 $self->{attrs}{alias} => $source->from,
3618 if ( $attrs->{join} || $attrs->{prefetch} ) {
3620 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3621 if ref $attrs->{from} ne 'ARRAY';
3623 my $join = (delete $attrs->{join}) || {};
3625 if ( defined $attrs->{prefetch} ) {
3626 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3629 $attrs->{from} = # have to copy here to avoid corrupting the original
3631 @{ $attrs->{from} },
3632 $source->_resolve_join(
3635 { %{ $attrs->{seen_join} || {} } },
3636 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3637 ? $attrs->{from}[-1][0]{-join_path}
3645 for my $attr (qw(order_by group_by)) {
3647 if ( defined $attrs->{$attr} ) {
3649 ref( $attrs->{$attr} ) eq 'ARRAY'
3650 ? [ @{ $attrs->{$attr} } ]
3651 : [ $attrs->{$attr} || () ]
3654 delete $attrs->{$attr} unless @{$attrs->{$attr}};
3659 # set collapse default based on presence of prefetch
3662 defined $attrs->{prefetch}
3664 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3666 $self->throw_exception("Specifying prefetch in conjunction with an explicit collapse => 0 is unsupported")
3667 if defined $attrs->{collapse} and ! $attrs->{collapse};
3669 $attrs->{collapse} = 1;
3673 # run through the resulting joinstructure (starting from our current slot)
3674 # and unset collapse if proven unnecessary
3676 # also while we are at it find out if the current root source has
3677 # been premultiplied by previous related_source chaining
3679 # this allows to predict whether a root object with all other relation
3680 # data set to NULL is in fact unique
3681 if ($attrs->{collapse}) {
3683 if (ref $attrs->{from} eq 'ARRAY') {
3685 if (@{$attrs->{from}} == 1) {
3686 # no joins - no collapse
3687 $attrs->{collapse} = 0;
3690 # find where our table-spec starts
3691 my @fromlist = @{$attrs->{from}};
3693 my $t = shift @fromlist;
3696 # me vs join from-spec distinction - a ref means non-root
3697 if (ref $t eq 'ARRAY') {
3699 $is_multi ||= ! $t->{-is_single};
3701 last if ($t->{-alias} && $t->{-alias} eq $alias);
3702 $attrs->{_main_source_premultiplied} ||= $is_multi;
3705 # no non-singles remaining, nor any premultiplication - nothing to collapse
3707 ! $attrs->{_main_source_premultiplied}
3709 ! List::Util::first { ! $_->[0]{-is_single} } @fromlist
3711 $attrs->{collapse} = 0;
3717 # if we can not analyze the from - err on the side of safety
3718 $attrs->{_main_source_premultiplied} = 1;
3723 # generate the distinct induced group_by before injecting the prefetched select/as parts
3724 if (delete $attrs->{distinct}) {
3725 if ($attrs->{group_by}) {
3726 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3729 $attrs->{_grouped_by_distinct} = 1;
3730 # distinct affects only the main selection part, not what prefetch may add below
3731 ($attrs->{group_by}, my $new_order) = $source->storage->_group_over_selection($attrs);
3733 # FIXME possibly ignore a rewritten order_by (may turn out to be an issue)
3734 # The thinking is: if we are collapsing the subquerying prefetch engine will
3735 # rip stuff apart for us anyway, and we do not want to have a potentially
3736 # function-converted external order_by
3737 # ( there is an explicit if ( collapse && _grouped_by_distinct ) check in DBIHacks )
3738 $attrs->{order_by} = $new_order unless $attrs->{collapse};
3743 # generate selections based on the prefetch helper
3746 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3747 if $attrs->{_dark_selector};
3749 # this is a separate structure (we don't look in {from} directly)
3750 # as the resolver needs to shift things off the lists to work
3751 # properly (identical-prefetches on different branches)
3752 my $joined_node_aliases_map = {};
3753 if (ref $attrs->{from} eq 'ARRAY') {
3755 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3757 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3758 next unless $j->[0]{-alias};
3759 next unless $j->[0]{-join_path};
3760 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3762 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3764 my $p = $joined_node_aliases_map;
3765 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3766 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3770 ( push @{$attrs->{select}}, $_->[0] ) and ( push @{$attrs->{as}}, $_->[1] )
3771 for $source->_resolve_selection_from_prefetch( $prefetch, $joined_node_aliases_map );
3775 $attrs->{_simple_passthrough_construction} = !(
3778 grep { $_ =~ /\./ } @{$attrs->{as}}
3782 # if both page and offset are specified, produce a combined offset
3783 # even though it doesn't make much sense, this is what pre 081xx has
3785 if (my $page = delete $attrs->{page}) {
3787 ($attrs->{rows} * ($page - 1))
3789 ($attrs->{offset} || 0)
3793 return $self->{_attrs} = $attrs;
3797 my ($self, $attr) = @_;
3799 if (ref $attr eq 'HASH') {
3800 return $self->_rollout_hash($attr);
3801 } elsif (ref $attr eq 'ARRAY') {
3802 return $self->_rollout_array($attr);
3808 sub _rollout_array {
3809 my ($self, $attr) = @_;
3812 foreach my $element (@{$attr}) {
3813 if (ref $element eq 'HASH') {
3814 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3815 } elsif (ref $element eq 'ARRAY') {
3816 # XXX - should probably recurse here
3817 push( @rolled_array, @{$self->_rollout_array($element)} );
3819 push( @rolled_array, $element );
3822 return \@rolled_array;
3826 my ($self, $attr) = @_;
3829 foreach my $key (keys %{$attr}) {
3830 push( @rolled_array, { $key => $attr->{$key} } );
3832 return \@rolled_array;
3835 sub _calculate_score {
3836 my ($self, $a, $b) = @_;
3838 if (defined $a xor defined $b) {
3841 elsif (not defined $a) {
3845 if (ref $b eq 'HASH') {
3846 my ($b_key) = keys %{$b};
3847 $b_key = '' if ! defined $b_key;
3848 if (ref $a eq 'HASH') {
3849 my ($a_key) = keys %{$a};
3850 $a_key = '' if ! defined $a_key;
3851 if ($a_key eq $b_key) {
3852 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3857 return ($a eq $b_key) ? 1 : 0;
3860 if (ref $a eq 'HASH') {
3861 my ($a_key) = keys %{$a};
3862 return ($b eq $a_key) ? 1 : 0;
3864 return ($b eq $a) ? 1 : 0;
3869 sub _merge_joinpref_attr {
3870 my ($self, $orig, $import) = @_;
3872 return $import unless defined($orig);
3873 return $orig unless defined($import);
3875 $orig = $self->_rollout_attr($orig);
3876 $import = $self->_rollout_attr($import);
3879 foreach my $import_element ( @{$import} ) {
3880 # find best candidate from $orig to merge $b_element into
3881 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3882 foreach my $orig_element ( @{$orig} ) {
3883 my $score = $self->_calculate_score( $orig_element, $import_element );
3884 if ($score > $best_candidate->{score}) {
3885 $best_candidate->{position} = $position;
3886 $best_candidate->{score} = $score;
3890 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3891 $import_key = '' if not defined $import_key;
3893 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3894 push( @{$orig}, $import_element );
3896 my $orig_best = $orig->[$best_candidate->{position}];
3897 # merge orig_best and b_element together and replace original with merged
3898 if (ref $orig_best ne 'HASH') {
3899 $orig->[$best_candidate->{position}] = $import_element;
3900 } elsif (ref $import_element eq 'HASH') {
3901 my ($key) = keys %{$orig_best};
3902 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3905 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3908 return @$orig ? $orig : ();
3916 require Hash::Merge;
3917 my $hm = Hash::Merge->new;
3919 $hm->specify_behavior({
3922 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3924 if ($defl xor $defr) {
3925 return [ $defl ? $_[0] : $_[1] ];
3930 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3934 return [$_[0], $_[1]];
3938 return $_[1] if !defined $_[0];
3939 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3940 return [$_[0], @{$_[1]}]
3943 return [] if !defined $_[0] and !keys %{$_[1]};
3944 return [ $_[1] ] if !defined $_[0];
3945 return [ $_[0] ] if !keys %{$_[1]};
3946 return [$_[0], $_[1]]
3951 return $_[0] if !defined $_[1];
3952 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3953 return [@{$_[0]}, $_[1]]
3956 my @ret = @{$_[0]} or return $_[1];
3957 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3958 my %idx = map { $_ => 1 } @ret;
3959 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3963 return [ $_[1] ] if ! @{$_[0]};
3964 return $_[0] if !keys %{$_[1]};
3965 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3966 return [ @{$_[0]}, $_[1] ];
3971 return [] if !keys %{$_[0]} and !defined $_[1];
3972 return [ $_[0] ] if !defined $_[1];
3973 return [ $_[1] ] if !keys %{$_[0]};
3974 return [$_[0], $_[1]]
3977 return [] if !keys %{$_[0]} and !@{$_[1]};
3978 return [ $_[0] ] if !@{$_[1]};
3979 return $_[1] if !keys %{$_[0]};
3980 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3981 return [ $_[0], @{$_[1]} ];
3984 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3985 return [ $_[0] ] if !keys %{$_[1]};
3986 return [ $_[1] ] if !keys %{$_[0]};
3987 return [ $_[0] ] if $_[0] eq $_[1];
3988 return [ $_[0], $_[1] ];
3991 } => 'DBIC_RS_ATTR_MERGER');
3995 return $hm->merge ($_[1], $_[2]);
3999 sub STORABLE_freeze {
4000 my ($self, $cloning) = @_;
4001 my $to_serialize = { %$self };
4003 # A cursor in progress can't be serialized (and would make little sense anyway)
4004 # the parser can be regenerated (and can't be serialized)
4005 delete @{$to_serialize}{qw/cursor _row_parser _result_inflator/};
4007 # nor is it sensical to store a not-yet-fired-count pager
4008 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
4009 delete $to_serialize->{pager};
4012 Storable::nfreeze($to_serialize);
4015 # need this hook for symmetry
4017 my ($self, $cloning, $serialized) = @_;
4019 %$self = %{ Storable::thaw($serialized) };
4025 =head2 throw_exception
4027 See L<DBIx::Class::Schema/throw_exception> for details.
4031 sub throw_exception {
4034 if (ref $self and my $rsrc = $self->result_source) {
4035 $rsrc->throw_exception(@_)
4038 DBIx::Class::Exception->throw(@_);
4046 # XXX: FIXME: Attributes docs need clearing up
4050 Attributes are used to refine a ResultSet in various ways when
4051 searching for data. They can be passed to any method which takes an
4052 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
4055 Default attributes can be set on the result class using
4056 L<DBIx::Class::ResultSource/resultset_attributes>. (Please read
4057 the CAVEATS on that feature before using it!)
4059 These are in no particular order:
4065 =item Value: ( $order_by | \@order_by | \%order_by )
4069 Which column(s) to order the results by.
4071 [The full list of suitable values is documented in
4072 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
4075 If a single column name, or an arrayref of names is supplied, the
4076 argument is passed through directly to SQL. The hashref syntax allows
4077 for connection-agnostic specification of ordering direction:
4079 For descending order:
4081 order_by => { -desc => [qw/col1 col2 col3/] }
4083 For explicit ascending order:
4085 order_by => { -asc => 'col' }
4087 The old scalarref syntax (i.e. order_by => \'year DESC') is still
4088 supported, although you are strongly encouraged to use the hashref
4089 syntax as outlined above.
4095 =item Value: \@columns | \%columns | $column
4099 Shortcut to request a particular set of columns to be retrieved. Each
4100 column spec may be a string (a table column name), or a hash (in which
4101 case the key is the C<as> value, and the value is used as the C<select>
4102 expression). Adds the L</current_source_alias> onto the start of any column without a C<.> in
4103 it and sets C<select> from that, then auto-populates C<as> from
4104 C<select> as normal. (You may also use the C<cols> attribute, as in
4105 earlier versions of DBIC, but this is deprecated)
4107 Essentially C<columns> does the same as L</select> and L</as>.
4109 columns => [ 'some_column', { dbic_slot => 'another_column' } ]
4113 select => [qw(some_column another_column)],
4114 as => [qw(some_column dbic_slot)]
4116 If you want to individually retrieve related columns (in essence perform
4117 manual L</prefetch>) you have to make sure to specify the correct inflation slot
4118 chain such that it matches existing relationships:
4120 my $rs = $schema->resultset('Artist')->search({}, {
4121 # required to tell DBIC to collapse has_many relationships
4123 join => { cds => 'tracks' },
4125 'cds.cdid' => 'cds.cdid',
4126 'cds.tracks.title' => 'tracks.title',
4130 Like elsewhere, literal SQL or literal values can be included by using a
4131 scalar reference or a literal bind value, and these values will be available
4132 in the result with C<get_column> (see also
4133 L<SQL::Abstract/Literal SQL and value type operators>):
4135 # equivalent SQL: SELECT 1, 'a string', IF(my_column,?,?) ...
4136 # bind values: $true_value, $false_value
4140 bar => \q{'a string'},
4141 baz => \[ 'IF(my_column,?,?)', $true_value, $false_value ],
4147 B<NOTE:> You B<MUST> explicitly quote C<'+columns'> when using this attribute.
4148 Not doing so causes Perl to incorrectly interpret C<+columns> as a bareword
4149 with a unary plus operator before it, which is the same as simply C<columns>.
4153 =item Value: \@extra_columns
4157 Indicates additional columns to be selected from storage. Works the same as
4158 L</columns> but adds columns to the current selection. (You may also use the
4159 C<include_columns> attribute, as in earlier versions of DBIC, but this is
4162 $schema->resultset('CD')->search(undef, {
4163 '+columns' => ['artist.name'],
4167 would return all CDs and include a 'name' column to the information
4168 passed to object inflation. Note that the 'artist' is the name of the
4169 column (or relationship) accessor, and 'name' is the name of the column
4170 accessor in the related table.
4176 =item Value: \@select_columns
4180 Indicates which columns should be selected from the storage. You can use
4181 column names, or in the case of RDBMS back ends, function or stored procedure
4184 $rs = $schema->resultset('Employee')->search(undef, {
4187 { count => 'employeeid' },
4188 { max => { length => 'name' }, -as => 'longest_name' }
4193 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
4195 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
4196 use L</select>, to instruct DBIx::Class how to store the result of the column.
4198 Also note that the L</as> attribute has B<nothing to do> with the SQL-side
4199 C<AS> identifier aliasing. You B<can> alias a function (so you can use it e.g.
4200 in an C<ORDER BY> clause), however this is done via the C<-as> B<select
4201 function attribute> supplied as shown in the example above.
4205 B<NOTE:> You B<MUST> explicitly quote C<'+select'> when using this attribute.
4206 Not doing so causes Perl to incorrectly interpret C<+select> as a bareword
4207 with a unary plus operator before it, which is the same as simply C<select>.
4211 =item Value: \@extra_select_columns
4215 Indicates additional columns to be selected from storage. Works the same as
4216 L</select> but adds columns to the current selection, instead of specifying
4217 a new explicit list.
4223 =item Value: \@inflation_names
4227 Indicates DBIC-side names for object inflation. That is L</as> indicates the
4228 slot name in which the column value will be stored within the
4229 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
4230 identifier by the C<get_column> method (or via the object accessor B<if one
4231 with the same name already exists>) as shown below.
4233 The L</as> attribute has B<nothing to do> with the SQL-side identifier
4234 aliasing C<AS>. See L</select> for details.
4236 $rs = $schema->resultset('Employee')->search(undef, {
4239 { count => 'employeeid' },
4240 { max => { length => 'name' }, -as => 'longest_name' }
4249 If the object against which the search is performed already has an accessor
4250 matching a column name specified in C<as>, the value can be retrieved using
4251 the accessor as normal:
4253 my $name = $employee->name();
4255 If on the other hand an accessor does not exist in the object, you need to
4256 use C<get_column> instead:
4258 my $employee_count = $employee->get_column('employee_count');
4260 You can create your own accessors if required - see
4261 L<DBIx::Class::Manual::Cookbook> for details.
4265 B<NOTE:> You B<MUST> explicitly quote C<'+as'> when using this attribute.
4266 Not doing so causes Perl to incorrectly interpret C<+as> as a bareword
4267 with a unary plus operator before it, which is the same as simply C<as>.
4271 =item Value: \@extra_inflation_names
4275 Indicates additional inflation names for selectors added via L</+select>. See L</as>.
4281 =item Value: ($rel_name | \@rel_names | \%rel_names)
4285 Contains a list of relationships that should be joined for this query. For
4288 # Get CDs by Nine Inch Nails
4289 my $rs = $schema->resultset('CD')->search(
4290 { 'artist.name' => 'Nine Inch Nails' },
4291 { join => 'artist' }
4294 Can also contain a hash reference to refer to the other relation's relations.
4297 package MyApp::Schema::Track;
4298 use base qw/DBIx::Class/;
4299 __PACKAGE__->table('track');
4300 __PACKAGE__->add_columns(qw/trackid cd position title/);
4301 __PACKAGE__->set_primary_key('trackid');
4302 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
4305 # In your application
4306 my $rs = $schema->resultset('Artist')->search(
4307 { 'track.title' => 'Teardrop' },
4309 join => { cd => 'track' },
4310 order_by => 'artist.name',
4314 You need to use the relationship (not the table) name in conditions,
4315 because they are aliased as such. The current table is aliased as "me", so
4316 you need to use me.column_name in order to avoid ambiguity. For example:
4318 # Get CDs from 1984 with a 'Foo' track
4319 my $rs = $schema->resultset('CD')->search(
4322 'tracks.name' => 'Foo'
4324 { join => 'tracks' }
4327 If the same join is supplied twice, it will be aliased to <rel>_2 (and
4328 similarly for a third time). For e.g.
4330 my $rs = $schema->resultset('Artist')->search({
4331 'cds.title' => 'Down to Earth',
4332 'cds_2.title' => 'Popular',
4334 join => [ qw/cds cds/ ],
4337 will return a set of all artists that have both a cd with title 'Down
4338 to Earth' and a cd with title 'Popular'.
4340 If you want to fetch related objects from other tables as well, see L</prefetch>
4343 NOTE: An internal join-chain pruner will discard certain joins while
4344 constructing the actual SQL query, as long as the joins in question do not
4345 affect the retrieved result. This for example includes 1:1 left joins
4346 that are not part of the restriction specification (WHERE/HAVING) nor are
4347 a part of the query selection.
4349 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4355 =item Value: (0 | 1)
4359 When set to a true value, indicates that any rows fetched from joined has_many
4360 relationships are to be aggregated into the corresponding "parent" object. For
4361 example, the resultset:
4363 my $rs = $schema->resultset('CD')->search({}, {
4364 '+columns' => [ qw/ tracks.title tracks.position / ],
4369 While executing the following query:
4371 SELECT me.*, tracks.title, tracks.position
4373 LEFT JOIN track tracks
4374 ON tracks.cdid = me.cdid
4376 Will return only as many objects as there are rows in the CD source, even
4377 though the result of the query may span many rows. Each of these CD objects
4378 will in turn have multiple "Track" objects hidden behind the has_many
4379 generated accessor C<tracks>. Without C<< collapse => 1 >>, the return values
4380 of this resultset would be as many CD objects as there are tracks (a "Cartesian
4381 product"), with each CD object containing exactly one of all fetched Track data.
4383 When a collapse is requested on a non-ordered resultset, an order by some
4384 unique part of the main source (the left-most table) is inserted automatically.
4385 This is done so that the resultset is allowed to be "lazy" - calling
4386 L<< $rs->next|/next >> will fetch only as many rows as it needs to build the next
4387 object with all of its related data.
4389 If an L</order_by> is already declared, and orders the resultset in a way that
4390 makes collapsing as described above impossible (e.g. C<< ORDER BY
4391 has_many_rel.column >> or C<ORDER BY RANDOM()>), DBIC will automatically
4392 switch to "eager" mode and slurp the entire resultset before constructing the
4393 first object returned by L</next>.
4395 Setting this attribute on a resultset that does not join any has_many
4396 relations is a no-op.
4398 For a more in-depth discussion, see L</PREFETCHING>.
4404 =item Value: ($rel_name | \@rel_names | \%rel_names)
4408 This attribute is a shorthand for specifying a L</join> spec, adding all
4409 columns from the joined related sources as L</+columns> and setting
4410 L</collapse> to a true value. It can be thought of as a rough B<superset>
4411 of the L</join> attribute.
4413 For example, the following two queries are equivalent:
4415 my $rs = $schema->resultset('Artist')->search({}, {
4416 prefetch => { cds => ['genre', 'tracks' ] },
4421 my $rs = $schema->resultset('Artist')->search({}, {
4422 join => { cds => ['genre', 'tracks' ] },
4426 { +{ "cds.$_" => "cds.$_" } }
4427 $schema->source('Artist')->related_source('cds')->columns
4430 { +{ "cds.genre.$_" => "genre.$_" } }
4431 $schema->source('Artist')->related_source('cds')->related_source('genre')->columns
4434 { +{ "cds.tracks.$_" => "tracks.$_" } }
4435 $schema->source('Artist')->related_source('cds')->related_source('tracks')->columns
4440 Both producing the following SQL:
4442 SELECT me.artistid, me.name, me.rank, me.charfield,
4443 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track,
4444 genre.genreid, genre.name,
4445 tracks.trackid, tracks.cd, tracks.position, tracks.title, tracks.last_updated_on, tracks.last_updated_at
4448 ON cds.artist = me.artistid
4449 LEFT JOIN genre genre
4450 ON genre.genreid = cds.genreid
4451 LEFT JOIN track tracks
4452 ON tracks.cd = cds.cdid
4453 ORDER BY me.artistid
4455 While L</prefetch> implies a L</join>, it is ok to mix the two together, as
4456 the arguments are properly merged and generally do the right thing. For
4457 example, you may want to do the following:
4459 my $artists_and_cds_without_genre = $schema->resultset('Artist')->search(
4460 { 'genre.genreid' => undef },
4462 join => { cds => 'genre' },
4467 Which generates the following SQL:
4469 SELECT me.artistid, me.name, me.rank, me.charfield,
4470 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track
4473 ON cds.artist = me.artistid
4474 LEFT JOIN genre genre
4475 ON genre.genreid = cds.genreid
4476 WHERE genre.genreid IS NULL
4477 ORDER BY me.artistid
4479 For a more in-depth discussion, see L</PREFETCHING>.
4485 =item Value: $source_alias
4489 Sets the source alias for the query. Normally, this defaults to C<me>, but
4490 nested search queries (sub-SELECTs) might need specific aliases set to
4491 reference inner queries. For example:
4494 ->related_resultset('CDs')
4495 ->related_resultset('Tracks')
4497 'track.id' => { -ident => 'none_search.id' },
4501 my $ids = $self->search({
4504 alias => 'none_search',
4505 group_by => 'none_search.id',
4506 })->get_column('id')->as_query;
4508 $self->search({ id => { -in => $ids } })
4510 This attribute is directly tied to L</current_source_alias>.
4520 Makes the resultset paged and specifies the page to retrieve. Effectively
4521 identical to creating a non-pages resultset and then calling ->page($page)
4524 If L</rows> attribute is not specified it defaults to 10 rows per page.
4526 When you have a paged resultset, L</count> will only return the number
4527 of rows in the page. To get the total, use the L</pager> and call
4528 C<total_entries> on it.
4538 Specifies the maximum number of rows for direct retrieval or the number of
4539 rows per page if the page attribute or method is used.
4545 =item Value: $offset
4549 Specifies the (zero-based) row number for the first row to be returned, or the
4550 of the first row of the first page if paging is used.
4552 =head2 software_limit
4556 =item Value: (0 | 1)
4560 When combined with L</rows> and/or L</offset> the generated SQL will not
4561 include any limit dialect stanzas. Instead the entire result will be selected
4562 as if no limits were specified, and DBIC will perform the limit locally, by
4563 artificially advancing and finishing the resulting L</cursor>.
4565 This is the recommended way of performing resultset limiting when no sane RDBMS
4566 implementation is available (e.g.
4567 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4568 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4574 =item Value: \@columns
4578 A arrayref of columns to group by. Can include columns of joined tables.
4580 group_by => [qw/ column1 column2 ... /]
4586 =item Value: $condition
4590 The HAVING operator specifies a B<secondary> condition applied to the set
4591 after the grouping calculations have been done. In other words it is a
4592 constraint just like L</where> (and accepting the same
4593 L<SQL::Abstract syntax|SQL::Abstract/WHERE CLAUSES>) applied to the data
4594 as it exists after GROUP BY has taken place. Specifying L</having> without
4595 L</group_by> is a logical mistake, and a fatal error on most RDBMS engines.
4599 having => { 'count_employee' => { '>=', 100 } }
4601 or with an in-place function in which case literal SQL is required:
4603 having => \[ 'count(employee) >= ?', 100 ]
4609 =item Value: (0 | 1)
4613 Set to 1 to automatically generate a L</group_by> clause based on the selection
4614 (including intelligent handling of L</order_by> contents). Note that the group
4615 criteria calculation takes place over the B<final> selection. This includes
4616 any L</+columns>, L</+select> or L</order_by> additions in subsequent
4617 L</search> calls, and standalone columns selected via
4618 L<DBIx::Class::ResultSetColumn> (L</get_column>). A notable exception are the
4619 extra selections specified via L</prefetch> - such selections are explicitly
4620 excluded from group criteria calculations.
4622 If the final ResultSet also explicitly defines a L</group_by> attribute, this
4623 setting is ignored and an appropriate warning is issued.
4627 Adds extra conditions to the resultset, combined with the preexisting C<WHERE>
4628 conditions, same as the B<first> argument to the L<search operator|/search>
4630 # only return rows WHERE deleted IS NULL for all searches
4631 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4633 Note that the above example is
4634 L<strongly discouraged|DBIx::Class::ResultSource/resultset_attributes>.
4638 Set to 1 to cache search results. This prevents extra SQL queries if you
4639 revisit rows in your ResultSet:
4641 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4643 while( my $artist = $resultset->next ) {
4647 $resultset->first; # without cache, this would issue a query
4649 By default, searches are not cached.
4651 For more examples of using these attributes, see
4652 L<DBIx::Class::Manual::Cookbook>.
4658 =item Value: ( 'update' | 'shared' | \$scalar )
4662 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4663 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4668 DBIx::Class supports arbitrary related data prefetching from multiple related
4669 sources. Any combination of relationship types and column sets are supported.
4670 If L<collapsing|/collapse> is requested, there is an additional requirement of
4671 selecting enough data to make every individual object uniquely identifiable.
4673 Here are some more involved examples, based on the following relationship map:
4676 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4677 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4678 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4680 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4682 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4686 my $rs = $schema->resultset('Tag')->search(
4695 The initial search results in SQL like the following:
4697 SELECT tag.*, cd.*, artist.* FROM tag
4698 JOIN cd ON tag.cd = cd.cdid
4699 JOIN artist ON cd.artist = artist.artistid
4701 L<DBIx::Class> has no need to go back to the database when we access the
4702 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4705 Simple prefetches will be joined automatically, so there is no need
4706 for a C<join> attribute in the above search.
4708 The L</prefetch> attribute can be used with any of the relationship types
4709 and multiple prefetches can be specified together. Below is a more complex
4710 example that prefetches a CD's artist, its liner notes (if present),
4711 the cover image, the tracks on that CD, and the guests on those
4714 my $rs = $schema->resultset('CD')->search(
4718 { artist => 'record_label'}, # belongs_to => belongs_to
4719 'liner_note', # might_have
4720 'cover_image', # has_one
4721 { tracks => 'guests' }, # has_many => has_many
4726 This will produce SQL like the following:
4728 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4732 ON artist.artistid = me.artistid
4733 JOIN record_label record_label
4734 ON record_label.labelid = artist.labelid
4735 LEFT JOIN track tracks
4736 ON tracks.cdid = me.cdid
4737 LEFT JOIN guest guests
4738 ON guests.trackid = track.trackid
4739 LEFT JOIN liner_notes liner_note
4740 ON liner_note.cdid = me.cdid
4741 JOIN cd_artwork cover_image
4742 ON cover_image.cdid = me.cdid
4745 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4746 C<tracks>, and C<guests> of the CD will all be available through the
4747 relationship accessors without the need for additional queries to the
4752 Prefetch does a lot of deep magic. As such, it may not behave exactly
4753 as you might expect.
4759 Prefetch uses the L</cache> to populate the prefetched relationships. This
4760 may or may not be what you want.
4764 If you specify a condition on a prefetched relationship, ONLY those
4765 rows that match the prefetched condition will be fetched into that relationship.
4766 This means that adding prefetch to a search() B<may alter> what is returned by
4767 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4769 my $artist_rs = $schema->resultset('Artist')->search({
4775 my $count = $artist_rs->first->cds->count;
4777 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4779 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4781 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4783 That cmp_ok() may or may not pass depending on the datasets involved. In other
4784 words the C<WHERE> condition would apply to the entire dataset, just like
4785 it would in regular SQL. If you want to add a condition only to the "right side"
4786 of a C<LEFT JOIN> - consider declaring and using a L<relationship with a custom
4787 condition|DBIx::Class::Relationship::Base/condition>
4791 =head1 DBIC BIND VALUES
4793 Because DBIC may need more information to bind values than just the column name
4794 and value itself, it uses a special format for both passing and receiving bind
4795 values. Each bind value should be composed of an arrayref of
4796 C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
4802 If present (in any form), this is what is being passed directly to bind_param.
4803 Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
4804 a single numerical type, while DBD::Pg takes a hashref if bind options.)
4806 If this is specified, all other bind options described below are ignored.
4810 If present, this is used to infer the actual bind attribute by passing to
4811 C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
4812 "data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
4814 Note that the data type is somewhat freeform (hence the sqlt_ prefix);
4815 currently drivers are expected to "Do the Right Thing" when given a common
4816 datatype name. (Not ideal, but that's what we got at this point.)
4820 Currently used to correctly allocate buffers for bind_param_inout().
4821 Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
4822 or to a sensible value based on the "data_type".
4826 Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
4827 explicitly specified they are never overridden). Also used by some weird DBDs,
4828 where the column name should be available at bind_param time (e.g. Oracle).
4832 For backwards compatibility and convenience, the following shortcuts are
4835 [ $name => $val ] === [ { dbic_colname => $name }, $val ]
4836 [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
4837 [ undef, $val ] === [ {}, $val ]
4838 $val === [ {}, $val ]
4840 =head1 FURTHER QUESTIONS?
4842 Check the list of L<additional DBIC resources|DBIx::Class/GETTING HELP/SUPPORT>.
4844 =head1 COPYRIGHT AND LICENSE
4846 This module is free software L<copyright|DBIx::Class/COPYRIGHT AND LICENSE>
4847 by the L<DBIx::Class (DBIC) authors|DBIx::Class/AUTHORS>. You can
4848 redistribute it and/or modify it under the same terms as the
4849 L<DBIx::Class library|DBIx::Class/COPYRIGHT AND LICENSE>.