1 package DBIx::Class::ResultSet;
6 use base 'DBIx::Class';
9 use DBIx::Class::ResultSetColumn;
10 use DBIx::Class::ResultClass::HashRefInflator;
11 use Scalar::Util qw( blessed reftype );
12 use SQL::Abstract 'is_literal_value';
13 use DBIx::Class::_Util qw(
14 dbic_internal_try dbic_internal_catch dump_value emit_loud_diag
15 fail_on_internal_call UNRESOLVABLE_CONDITION DUMMY_ALIASPAIR
17 use DBIx::Class::SQLMaker::Util qw( normalize_sqla_condition extract_equality_conditions );
18 use DBIx::Class::ResultSource::FromSpec::Util 'find_join_path_to_alias';
21 # De-duplication in _merge_attr() is disabled, but left in for reference
22 # (the merger is used for other things that ought not to be de-duped)
23 *__HM_DEDUP = sub () { 0 };
33 # this is real - CDBICompat overrides it with insanity
34 # yes, prototype won't matter, but that's for now ;)
37 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class result_source/);
41 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
45 my $users_rs = $schema->resultset('User');
46 while( $user = $users_rs->next) {
47 print $user->username;
50 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
51 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
55 A ResultSet is an object which stores a set of conditions representing
56 a query. It is the backbone of DBIx::Class (i.e. the really
57 important/useful bit).
59 No SQL is executed on the database when a ResultSet is created, it
60 just stores all the conditions needed to create the query.
62 A basic ResultSet representing the data of an entire table is returned
63 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
64 L<Source|DBIx::Class::Manual::Glossary/ResultSource> name.
66 my $users_rs = $schema->resultset('User');
68 A new ResultSet is returned from calling L</search> on an existing
69 ResultSet. The new one will contain all the conditions of the
70 original, plus any new conditions added in the C<search> call.
72 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
73 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
76 The query that the ResultSet represents is B<only> executed against
77 the database when these methods are called:
78 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
80 If a resultset is used in a numeric context it returns the L</count>.
81 However, if it is used in a boolean context it is B<always> true. So if
82 you want to check if a resultset has any results, you must use C<if $rs
87 =head2 Chaining resultsets
89 Let's say you've got a query that needs to be run to return some data
90 to the user. But, you have an authorization system in place that
91 prevents certain users from seeing certain information. So, you want
92 to construct the basic query in one method, but add constraints to it in
97 my $request = $self->get_request; # Get a request object somehow.
98 my $schema = $self->result_source->schema;
100 my $cd_rs = $schema->resultset('CD')->search({
101 title => $request->param('title'),
102 year => $request->param('year'),
105 $cd_rs = $self->apply_security_policy( $cd_rs );
107 return $cd_rs->all();
110 sub apply_security_policy {
119 =head3 Resolving conditions and attributes
121 When a resultset is chained from another resultset (e.g.:
122 C<< my $new_rs = $old_rs->search(\%extra_cond, \%attrs) >>), conditions
123 and attributes with the same keys need resolving.
125 If any of L</columns>, L</select>, L</as> are present, they reset the
126 original selection, and start the selection "clean".
128 The L</join>, L</prefetch>, L</+columns>, L</+select>, L</+as> attributes
129 are merged into the existing ones from the original resultset.
131 The L</where> and L</having> attributes, and any search conditions, are
132 merged with an SQL C<AND> to the existing condition from the original
135 All other attributes are overridden by any new ones supplied in the
138 =head2 Multiple queries
140 Since a resultset just defines a query, you can do all sorts of
141 things with it with the same object.
143 # Don't hit the DB yet.
144 my $cd_rs = $schema->resultset('CD')->search({
145 title => 'something',
149 # Each of these hits the DB individually.
150 my $count = $cd_rs->count;
151 my $most_recent = $cd_rs->get_column('date_released')->max();
152 my @records = $cd_rs->all;
154 And it's not just limited to SELECT statements.
160 $cd_rs->create({ artist => 'Fred' });
162 Which is the same as:
164 $schema->resultset('CD')->create({
165 title => 'something',
170 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
172 =head2 Custom ResultSet classes
174 To add methods to your resultsets, you can subclass L<DBIx::Class::ResultSet>, similar to:
176 package MyApp::Schema::ResultSet::User;
181 use base 'DBIx::Class::ResultSet';
185 $self->search({ $self->current_source_alias . '.active' => 1 });
190 $self->search({ $self->current_source_alias . '.verified' => 0 });
193 sub created_n_days_ago {
194 my ($self, $days_ago) = @_;
196 $self->current_source_alias . '.create_date' => {
198 $self->result_source->schema->storage->datetime_parser->format_datetime(
199 DateTime->now( time_zone => 'UTC' )->subtract( days => $days_ago )
204 sub users_to_warn { shift->active->unverified->created_n_days_ago(7) }
208 See L<DBIx::Class::Schema/load_namespaces> on how DBIC can discover and
209 automatically attach L<Result|DBIx::Class::Manual::ResultClass>-specific
210 L<ResulSet|DBIx::Class::ResultSet> classes.
212 =head3 ResultSet subclassing with Moose and similar constructor-providers
214 Using L<Moose> or L<Moo> in your ResultSet classes is usually overkill, but
215 you may find it useful if your ResultSets contain a lot of business logic
216 (e.g. C<has xml_parser>, C<has json>, etc) or if you just prefer to organize
219 In order to write custom ResultSet classes with L<Moo> you need to use the
220 following template. The L<BUILDARGS|Moo/BUILDARGS> is necessary due to the
221 unusual signature of the L<constructor provided by DBIC
222 |DBIx::Class::ResultSet/new> C<< ->new($source, \%args) >>.
225 extends 'DBIx::Class::ResultSet';
226 sub BUILDARGS { $_[2] } # ::RS::new() expects my ($class, $rsrc, $args) = @_
232 If you want to build your custom ResultSet classes with L<Moose>, you need
233 a similar, though a little more elaborate template in order to interface the
234 inlining of the L<Moose>-provided
235 L<object constructor|Moose::Manual::Construction/WHERE'S THE CONSTRUCTOR?>,
238 package MyApp::Schema::ResultSet::User;
241 use MooseX::NonMoose;
242 extends 'DBIx::Class::ResultSet';
244 sub BUILDARGS { $_[2] } # ::RS::new() expects my ($class, $rsrc, $args) = @_
248 __PACKAGE__->meta->make_immutable;
252 The L<MooseX::NonMoose> is necessary so that the L<Moose> constructor does not
253 entirely overwrite the DBIC one (in contrast L<Moo> does this automatically).
254 Alternatively, you can skip L<MooseX::NonMoose> and get by with just L<Moose>
257 __PACKAGE__->meta->make_immutable(inline_constructor => 0);
265 =item Arguments: L<$source|DBIx::Class::ResultSource>, L<\%attrs?|/ATTRIBUTES>
267 =item Return Value: L<$resultset|/search>
271 The resultset constructor. Takes a source object (usually a
272 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
273 L</ATTRIBUTES> below). Does not perform any queries -- these are
274 executed as needed by the other methods.
276 Generally you never construct a resultset manually. Instead you get one
278 C<< $schema->L<resultset|DBIx::Class::Schema/resultset>('$source_name') >>
279 or C<< $another_resultset->L<search|/search>(...) >> (the later called in
282 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
288 If called on an object, proxies to L</new_result> instead, so
290 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
292 will return a CD object, not a ResultSet, and is equivalent to:
294 my $cd = $schema->resultset('CD')->new_result({ title => 'Spoon' });
296 Please also keep in mind that many internals call L</new_result> directly,
297 so overloading this method with the idea of intercepting new result object
298 creation B<will not work>. See also warning pertaining to L</create>.
308 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
309 return $class->new_result(@_);
312 my ($source, $attrs) = @_;
313 $source = $source->resolve
314 if $source->isa('DBIx::Class::ResultSourceHandle');
316 $attrs = { %{$attrs||{}} };
317 delete @{$attrs}{qw(_last_sqlmaker_alias_map _simple_passthrough_construction)};
319 if ($attrs->{page}) {
320 $attrs->{rows} ||= 10;
323 $attrs->{alias} ||= 'me';
326 result_source => $source,
327 cond => $attrs->{where},
332 # if there is a dark selector, this means we are already in a
333 # chain and the cleanup/sanification was taken care of by
335 $self->_normalize_selection($attrs)
336 unless $attrs->{_dark_selector};
339 $attrs->{result_class} || $source->result_class
349 =item Arguments: L<$cond|DBIx::Class::SQLMaker> | undef, L<\%attrs?|/ATTRIBUTES>
351 =item Return Value: $resultset (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
355 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
356 my $new_rs = $cd_rs->search({ year => 2005 });
358 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
359 # year = 2005 OR year = 2004
361 In list context, C<< ->all() >> is called implicitly on the resultset, thus
362 returning a list of L<result|DBIx::Class::Manual::ResultClass> objects instead.
363 To avoid that, use L</search_rs>.
365 If you need to pass in additional attributes but no additional condition,
366 call it as C<search(undef, \%attrs)>.
368 # "SELECT name, artistid FROM $artist_table"
369 my @all_artists = $schema->resultset('Artist')->search(undef, {
370 columns => [qw/name artistid/],
373 For a list of attributes that can be passed to C<search>, see
374 L</ATTRIBUTES>. For more examples of using this function, see
375 L<Searching|DBIx::Class::Manual::Cookbook/SEARCHING>. For a complete
376 documentation for the first argument, see L<SQL::Abstract/"WHERE CLAUSES">
377 and its extension L<DBIx::Class::SQLMaker>.
379 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
383 Note that L</search> does not process/deflate any of the values passed in the
384 L<SQL::Abstract>-compatible search condition structure. This is unlike other
385 condition-bound methods L</new_result>, L</create> and L</find>. The user must ensure
386 manually that any value passed to this method will stringify to something the
387 RDBMS knows how to deal with. A notable example is the handling of L<DateTime>
388 objects, for more info see:
389 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
394 my $rs = shift->search_rs( @_ );
400 if defined wantarray;
402 # we can be called by a relationship helper, which in
403 # turn may be called in void context due to some braindead
404 # overload or whatever else the user decided to be clever
405 # at this particular day. Thus limit the exception to
406 # external code calls only
407 $rs->throw_exception ('->search is *not* a mutator, calling it in void context makes no sense')
408 if (caller)[0] !~ /^\QDBIx::Class::/;
410 # we are in void ctx here, but just in case
418 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
420 =item Return Value: L<$resultset|/search>
424 This method does the same exact thing as search() except it will
425 always return a resultset, even in list context.
432 my $rsrc = $self->result_source;
433 my ($call_cond, $call_attrs);
435 # Special-case handling for (undef, undef) or (undef)
436 # Note that (foo => undef) is valid deprecated syntax
437 @_ = () if not scalar grep { defined $_ } @_;
443 # fish out attrs in the ($condref, $attr) case
444 elsif (@_ == 2 and ( ! defined $_[0] or length ref $_[0] ) ) {
445 ($call_cond, $call_attrs) = @_;
448 $self->throw_exception('Odd number of arguments to search')
452 carp_unique 'search( %condition ) is deprecated, use search( \%condition ) instead'
453 unless $rsrc->result_class->isa('DBIx::Class::CDBICompat');
455 for my $i (0 .. $#_) {
457 $self->throw_exception ('All keys in condition key/value pairs must be plain scalars')
458 if (! defined $_[$i] or length ref $_[$i] );
464 # see if we can keep the cache (no $rs changes)
466 my %safe = (alias => 1, cache => 1);
467 if ( ! grep { !$safe{$_} } keys %$call_attrs and (
470 ref $call_cond eq 'HASH' && ! keys %$call_cond
472 ref $call_cond eq 'ARRAY' && ! @$call_cond
474 $cache = $self->get_cache;
477 my $old_attrs = { %{$self->{attrs}} };
478 my ($old_having, $old_where) = delete @{$old_attrs}{qw(having where)};
480 my $new_attrs = { %$old_attrs };
482 # take care of call attrs (only if anything is changing)
483 if ($call_attrs and keys %$call_attrs) {
485 # copy for _normalize_selection
486 $call_attrs = { %$call_attrs };
488 my @selector_attrs = qw/select as columns cols +select +as +columns include_columns/;
490 # reset the current selector list if new selectors are supplied
491 delete @{$old_attrs}{(@selector_attrs, '_dark_selector')}
492 if grep { exists $call_attrs->{$_} } qw(columns cols select as);
494 # Normalize the new selector list (operates on the passed-in attr structure)
495 # Need to do it on every chain instead of only once on _resolved_attrs, in
496 # order to allow detection of empty vs partial 'as'
497 $call_attrs->{_dark_selector} = $old_attrs->{_dark_selector}
498 if $old_attrs->{_dark_selector};
499 $self->_normalize_selection ($call_attrs);
501 # start with blind overwriting merge, exclude selector attrs
502 $new_attrs = { %{$old_attrs}, %{$call_attrs} };
503 delete @{$new_attrs}{@selector_attrs};
505 for (@selector_attrs) {
506 $new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
507 if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
510 # older deprecated name, use only if {columns} is not there
511 if (my $c = delete $new_attrs->{cols}) {
512 carp_unique( "Resultset attribute 'cols' is deprecated, use 'columns' instead" );
513 if ($new_attrs->{columns}) {
514 carp "Resultset specifies both the 'columns' and the legacy 'cols' attributes - ignoring 'cols'";
517 $new_attrs->{columns} = $c;
522 # join/prefetch use their own crazy merging heuristics
523 foreach my $key (qw/join prefetch/) {
524 $new_attrs->{$key} = $self->_merge_joinpref_attr($old_attrs->{$key}, $call_attrs->{$key})
525 if exists $call_attrs->{$key};
528 # stack binds together
529 $new_attrs->{bind} = [ @{ $old_attrs->{bind} || [] }, @{ $call_attrs->{bind} || [] } ];
533 for ($old_where, $call_cond) {
535 $new_attrs->{where} = $self->_stack_cond (
536 $_, $new_attrs->{where}
541 if (defined $old_having) {
542 $new_attrs->{having} = $self->_stack_cond (
543 $old_having, $new_attrs->{having}
547 my $rs = (ref $self)->new($rsrc, $new_attrs);
549 $rs->set_cache($cache) if ($cache);
554 sub _normalize_selection {
555 my ($self, $attrs) = @_;
558 if ( exists $attrs->{include_columns} ) {
559 carp_unique( "Resultset attribute 'include_columns' is deprecated, use '+columns' instead" );
560 $attrs->{'+columns'} = $self->_merge_attr(
561 $attrs->{'+columns'}, delete $attrs->{include_columns}
565 # columns are always placed first, however
567 # Keep the X vs +X separation until _resolved_attrs time - this allows to
568 # delay the decision on whether to use a default select list ($rsrc->columns)
569 # allowing stuff like the remove_columns helper to work
571 # select/as +select/+as pairs need special handling - the amount of select/as
572 # elements in each pair does *not* have to be equal (think multicolumn
573 # selectors like distinct(foo, bar) ). If the selector is bare (no 'as'
574 # supplied at all) - try to infer the alias, either from the -as parameter
575 # of the selector spec, or use the parameter whole if it looks like a column
576 # name (ugly legacy heuristic). If all fails - leave the selector bare (which
577 # is ok as well), but make sure no more additions to the 'as' chain take place
578 for my $pref ('', '+') {
580 my ($sel, $as) = map {
581 my $key = "${pref}${_}";
583 my $val = [ ref $attrs->{$key} eq 'ARRAY'
585 : $attrs->{$key} || ()
587 delete $attrs->{$key};
591 if (! @$as and ! @$sel ) {
594 elsif (@$as and ! @$sel) {
595 $self->throw_exception(
596 "Unable to handle ${pref}as specification (@$as) without a corresponding ${pref}select"
600 # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
601 # if any @$as has been supplied we assume the user knows what (s)he is doing
602 # and blindly keep stacking up pieces
603 unless ($attrs->{_dark_selector}) {
606 if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
607 push @$as, $_->{-as};
609 # assume any plain no-space, no-parenthesis string to be a column spec
610 # FIXME - this is retarded but is necessary to support shit like 'count(foo)'
611 elsif ( ! ref $_ and $_ =~ /^ [^\s\(\)]+ $/x) {
614 # if all else fails - raise a flag that no more aliasing will be allowed
616 $attrs->{_dark_selector} = {
619 local $Data::Dumper::Indent = 0;
628 elsif (@$as < @$sel) {
629 $self->throw_exception(
630 "Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
633 elsif ($pref and $attrs->{_dark_selector}) {
634 $self->throw_exception(
635 "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
641 $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
642 $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
647 my ($self, $left, $right) = @_;
650 (ref $_ eq 'ARRAY' and !@$_)
652 (ref $_ eq 'HASH' and ! keys %$_)
653 ) and $_ = undef for ($left, $right);
656 # either one of the two undef
657 ( (defined $left) xor (defined $right) ) ? ( defined $left ? $left : $right )
660 : ( ! defined $left ) ? undef
662 : { -and => [$left, $right] }
666 =head2 search_literal
668 B<CAVEAT>: C<search_literal> is provided for Class::DBI compatibility and
669 should only be used in that context. C<search_literal> is a convenience
670 method. It is equivalent to calling C<< $schema->search(\[]) >>, but if you
671 want to ensure columns are bound correctly, use L</search>.
673 See L<DBIx::Class::Manual::Cookbook/SEARCHING> and
674 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
675 require C<search_literal>.
679 =item Arguments: $sql_fragment, @standalone_bind_values
681 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
685 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
686 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
688 Pass a literal chunk of SQL to be added to the conditional part of the
691 Example of how to use C<search> instead of C<search_literal>
693 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
694 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
698 sub search_literal :DBIC_method_is_indirect_sugar {
699 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
701 my ($self, $sql, @bind) = @_;
703 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
706 return $self->search(\[ $sql, map [ {} => $_ ], @bind ], ($attr || () ));
713 =item Arguments: \%columns_values | @pk_values, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
715 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
719 Finds and returns a single row based on supplied criteria. Takes either a
720 hashref with the same format as L</create> (including inference of foreign
721 keys from related objects), or a list of primary key values in the same
722 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
723 declaration on the L</result_source>.
725 In either case an attempt is made to combine conditions already existing on
726 the resultset with the condition passed to this method.
728 To aid with preparing the correct query for the storage you may supply the
729 C<key> attribute, which is the name of a
730 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
731 unique constraint corresponding to the
732 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
733 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
734 to construct a query that satisfies the named unique constraint fully (
735 non-NULL values for each column member of the constraint) an exception is
738 If no C<key> is specified, the search is carried over all unique constraints
739 which are fully defined by the available condition.
741 If no such constraint is found, C<find> currently defaults to a simple
742 C<< search->(\%column_values) >> which may or may not do what you expect.
743 Note that this fallback behavior may be deprecated in further versions. If
744 you need to search with arbitrary conditions - use L</search>. If the query
745 resulting from this fallback produces more than one row, a warning to the
746 effect is issued, though only the first row is constructed and returned as
749 In addition to C<key>, L</find> recognizes and applies standard
750 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
752 Note that if you have extra concerns about the correctness of the resulting
753 query you need to specify the C<key> attribute and supply the entire condition
754 as an argument to find (since it is not always possible to perform the
755 combination of the resultset condition with the supplied one, especially if
756 the resultset condition contains literal sql).
758 For example, to find a row by its primary key:
760 my $cd = $schema->resultset('CD')->find(5);
762 You can also find a row by a specific unique constraint:
764 my $cd = $schema->resultset('CD')->find(
766 artist => 'Massive Attack',
767 title => 'Mezzanine',
769 { key => 'cd_artist_title' }
772 See also L</find_or_create> and L</update_or_create>.
778 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
782 if (exists $attrs->{key}) {
783 $constraint_name = defined $attrs->{key}
785 : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
789 # Parse out the condition from input
792 my $rsrc = $self->result_source;
794 if (ref $_[0] eq 'HASH') {
795 $call_cond = { %{$_[0]} };
798 # if only values are supplied we need to default to 'primary'
799 $constraint_name = 'primary' unless defined $constraint_name;
801 my @c_cols = $rsrc->unique_constraint_columns($constraint_name);
803 $self->throw_exception(
804 "No constraint columns, maybe a malformed '$constraint_name' constraint?"
807 $self->throw_exception (
808 'find() expects either a column/value hashref, or a list of values '
809 . "corresponding to the columns of the specified unique constraint '$constraint_name'"
810 ) unless @c_cols == @_;
812 @{$call_cond}{@c_cols} = @_;
815 # process relationship data if any
818 for my $key (keys %$call_cond) {
820 # either a structure or a result-ish object
821 length ref($call_cond->{$key})
823 ( $rel_list ||= { map { $_ => 1 } $rsrc->relationships } )
826 ! is_literal_value( $call_cond->{$key} )
828 # implicitly skip has_many's (likely MC), via the delete()
829 ( ref( my $foreign_val = delete $call_cond->{$key} ) ne 'ARRAY' )
832 # FIXME: it seems wrong that relationship conditions take precedence...?
836 %{ $rsrc->resolve_relationship_condition(
837 require_join_free_values => 1,
840 (! defined blessed $foreign_val) ? $foreign_val : do {
842 my $f_result_class = $rsrc->related_source($key)->result_class;
844 unless( $foreign_val->isa($f_result_class) ) {
846 $self->throw_exception(
847 'Objects supplied to find() must inherit from '
848 . "'$DBIx::Class::ResultSource::__expected_result_class_isa'"
849 ) unless $foreign_val->isa(
850 $DBIx::Class::ResultSource::__expected_result_class_isa
854 "Objects supplied to find() via '$key' usually should inherit from "
855 . "the related ResultClass ('$f_result_class'), perhaps you've made "
860 +{ $foreign_val->get_columns };
864 # an API where these are optional would be too cumbersome,
865 # instead always pass in some dummy values
867 )->{join_free_values} },
872 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
874 if (defined $constraint_name) {
875 $final_cond = $self->_qualify_cond_columns (
877 $rsrc->_minimal_valueset_satisfying_constraint(
878 constraint_name => $constraint_name,
879 values => ($self->_merge_with_rscond($call_cond))[0],
886 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
887 # This means that we got here after a merger of relationship conditions
888 # in ::Relationship::Base::search_related (the row method), and furthermore
889 # the relationship is of the 'single' type. This means that the condition
890 # provided by the relationship (already attached to $self) is sufficient,
891 # as there can be only one row in the database that would satisfy the
895 my (@unique_queries, %seen_column_combinations, $ci, @fc_exceptions);
897 # no key was specified - fall down to heuristics mode:
898 # run through all unique queries registered on the resultset, and
899 # 'OR' all qualifying queries together
901 # always start from 'primary' if it exists at all
902 for my $c_name ( sort {
904 : $b eq 'primary' ? 1
906 } $rsrc->unique_constraint_names) {
908 next if $seen_column_combinations{
909 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
913 push @unique_queries, $self->_qualify_cond_columns(
914 $rsrc->_minimal_valueset_satisfying_constraint(
915 constraint_name => $c_name,
916 values => ($self->_merge_with_rscond($call_cond))[0],
917 columns_info => ($ci ||= $rsrc->columns_info),
922 dbic_internal_catch {
923 push @fc_exceptions, $_ if $_ =~ /\bFilterColumn\b/;
928 @unique_queries ? \@unique_queries
929 : @fc_exceptions ? $self->throw_exception(join "; ", map { $_ =~ /(.*) at .+ line \d+$/s } @fc_exceptions )
930 : $self->_non_unique_find_fallback ($call_cond, $attrs)
934 # Run the query, passing the result_class since it should propagate for find
935 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
936 if ($rs->_resolved_attrs->{collapse}) {
938 carp "Query returned more than one row" if $rs->next;
946 # This is a stop-gap method as agreed during the discussion on find() cleanup:
947 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
949 # It is invoked when find() is called in legacy-mode with insufficiently-unique
950 # condition. It is provided for overrides until a saner way forward is devised
952 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
953 # the road. Please adjust your tests accordingly to catch this situation early
954 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
956 # The method will not be removed without an adequately complete replacement
957 # for strict-mode enforcement
958 sub _non_unique_find_fallback {
959 my ($self, $cond, $attrs) = @_;
961 return $self->_qualify_cond_columns(
963 exists $attrs->{alias}
965 : $self->{attrs}{alias}
970 sub _qualify_cond_columns {
971 my ($self, $cond, $alias) = @_;
973 my %aliased = %$cond;
974 for (keys %aliased) {
975 $aliased{"$alias.$_"} = delete $aliased{$_}
982 sub _build_unique_cond {
984 '_build_unique_cond is a private method, and moreover is about to go '
985 . 'away. Please contact the development team at %s if you believe you '
986 . 'have a genuine use for this method, in order to discuss alternatives.',
987 DBIx::Class::_ENV_::HELP_URL,
990 my ($self, $constraint_name, $cond, $croak_on_null) = @_;
992 $self->result_source->_minimal_valueset_satisfying_constraint(
993 constraint_name => $constraint_name,
995 carp_on_nulls => !$croak_on_null
999 =head2 search_related
1003 =item Arguments: $rel_name, $cond?, L<\%attrs?|/ATTRIBUTES>
1005 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1009 $new_rs = $cd_rs->search_related('artist', {
1013 Searches the specified relationship, optionally specifying a condition and
1014 attributes for matching records. See L</ATTRIBUTES> for more information.
1016 In list context, C<< ->all() >> is called implicitly on the resultset, thus
1017 returning a list of result objects instead. To avoid that, use L</search_related_rs>.
1019 See also L</search_related_rs>.
1023 sub search_related :DBIC_method_is_indirect_sugar {
1024 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1025 return shift->related_resultset(shift)->search(@_);
1028 =head2 search_related_rs
1030 This method works exactly the same as search_related, except that
1031 it guarantees a resultset, even in list context.
1035 sub search_related_rs :DBIC_method_is_indirect_sugar {
1036 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1037 return shift->related_resultset(shift)->search_rs(@_);
1044 =item Arguments: none
1046 =item Return Value: L<$cursor|DBIx::Class::Cursor>
1050 Returns a storage-driven cursor to the given resultset. See
1051 L<DBIx::Class::Cursor> for more information.
1058 return $self->{cursor} ||= do {
1059 my $attrs = $self->_resolved_attrs;
1060 $self->result_source->schema->storage->select(
1061 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
1070 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1072 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1076 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1078 Inflates the first result without creating a cursor if the resultset has
1079 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1082 While this method can take an optional search condition (just like L</search>)
1083 being a fast-code-path it does not recognize search attributes. If you need to
1084 add extra joins or similar, call L</search> and then chain-call L</single> on the
1085 L<DBIx::Class::ResultSet> returned.
1091 As of 0.08100, this method enforces the assumption that the preceding
1092 query returns only one row. If more than one row is returned, you will receive
1095 Query returned more than one row
1097 In this case, you should be using L</next> or L</find> instead, or if you really
1098 know what you are doing, use the L</rows> attribute to explicitly limit the size
1101 This method will also throw an exception if it is called on a resultset prefetching
1102 has_many, as such a prefetch implies fetching multiple rows from the database in
1103 order to assemble the resulting object.
1110 my ($self, $where) = @_;
1112 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1115 my $attrs = { %{$self->_resolved_attrs} };
1117 $self->throw_exception(
1118 'single() can not be used on resultsets collapsing a has_many. Use find( \%cond ) or next() instead'
1119 ) if $attrs->{collapse};
1122 if (defined $attrs->{where}) {
1125 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1126 $where, delete $attrs->{where} ]
1129 $attrs->{where} = $where;
1133 my $data = [ $self->result_source->schema->storage->select_single(
1134 $attrs->{from}, $attrs->{select},
1135 $attrs->{where}, $attrs
1138 return undef unless @$data;
1139 $self->{_stashed_rows} = [ $data ];
1140 $self->_construct_results->[0];
1147 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1149 =item Return Value: L<$resultsetcolumn|DBIx::Class::ResultSetColumn>
1153 my $max_length = $rs->get_column('length')->max;
1155 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1160 DBIx::Class::ResultSetColumn->new(@_);
1167 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1169 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1173 # WHERE title LIKE '%blue%'
1174 $cd_rs = $rs->search_like({ title => '%blue%'});
1176 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1177 that this is simply a convenience method retained for ex Class::DBI users.
1178 You most likely want to use L</search> with specific operators.
1180 For more information, see L<DBIx::Class::Manual::Cookbook>.
1182 This method is deprecated and will be removed in 0.09. Use L<search()|/search>
1183 instead. An example conversion is:
1185 ->search_like({ foo => 'bar' });
1189 ->search({ foo => { like => 'bar' } });
1193 sub search_like :DBIC_method_is_indirect_sugar {
1194 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1198 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1199 .' Instead use ->search({ x => { -like => "y%" } })'
1200 .' (note the outer pair of {}s - they are important!)'
1202 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
1203 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1204 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1205 return $class->search($query, { %$attrs });
1212 =item Arguments: $first, $last
1214 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1218 Returns a resultset or object list representing a subset of elements from the
1219 resultset slice is called on. Indexes are from 0, i.e., to get the first
1220 three records, call:
1222 my ($one, $two, $three) = $rs->slice(0, 2);
1226 sub slice :DBIC_method_is_indirect_sugar {
1227 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1229 my ($self, $min, $max) = @_;
1230 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1231 $attrs->{offset} = $self->{attrs}{offset} || 0;
1232 $attrs->{offset} += $min;
1233 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1234 return $self->search(undef, $attrs);
1241 =item Arguments: none
1243 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1247 Returns the next element in the resultset (C<undef> is there is none).
1249 Can be used to efficiently iterate over records in the resultset:
1251 my $rs = $schema->resultset('CD')->search;
1252 while (my $cd = $rs->next) {
1256 Note that you need to store the resultset object, and call C<next> on it.
1257 Calling C<< resultset('Table')->next >> repeatedly will always return the
1258 first record from the resultset.
1265 if (my $cache = $self->get_cache) {
1266 $self->{all_cache_position} ||= 0;
1267 return $cache->[$self->{all_cache_position}++];
1270 if ($self->{attrs}{cache}) {
1271 delete $self->{pager};
1272 $self->{all_cache_position} = 1;
1273 return ($self->all)[0];
1276 return shift(@{$self->{_stashed_results}}) if @{ $self->{_stashed_results}||[] };
1278 $self->{_stashed_results} = $self->_construct_results
1281 return shift @{$self->{_stashed_results}};
1284 # Constructs as many results as it can in one pass while respecting
1285 # cursor laziness. Several modes of operation:
1287 # * Always builds everything present in @{$self->{_stashed_rows}}
1288 # * If called with $fetch_all true - pulls everything off the cursor and
1289 # builds all result structures (or objects) in one pass
1290 # * If $self->_resolved_attrs->{collapse} is true, checks the order_by
1291 # and if the resultset is ordered properly by the left side:
1292 # * Fetches stuff off the cursor until the "master object" changes,
1293 # and saves the last extra row (if any) in @{$self->{_stashed_rows}}
1295 # * Just fetches, and collapses/constructs everything as if $fetch_all
1296 # was requested (there is no other way to collapse except for an
1298 # * If no collapse is requested - just get the next row, construct and
1300 sub _construct_results {
1301 my ($self, $fetch_all) = @_;
1303 my $rsrc = $self->result_source;
1304 my $attrs = $self->_resolved_attrs;
1309 ! $attrs->{order_by}
1313 my @pcols = $rsrc->primary_columns
1315 # default order for collapsing unless the user asked for something
1316 $attrs->{order_by} = [ map { join '.', $attrs->{alias}, $_} @pcols ];
1317 $attrs->{_ordered_for_collapse} = 1;
1318 $attrs->{_order_is_artificial} = 1;
1321 # this will be used as both initial raw-row collector AND as a RV of
1322 # _construct_results. Not regrowing the array twice matters a lot...
1323 # a surprising amount actually
1324 my $rows = delete $self->{_stashed_rows};
1326 my $cursor; # we may not need one at all
1328 my $did_fetch_all = $fetch_all;
1331 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1332 $rows = [ ($rows ? @$rows : ()), $self->cursor->all ];
1334 elsif( $attrs->{collapse} ) {
1336 # a cursor will need to be closed over in case of collapse
1337 $cursor = $self->cursor;
1339 $attrs->{_ordered_for_collapse} = (
1345 ->_extract_colinfo_of_stable_main_source_order_by_portion($attrs)
1347 ) unless defined $attrs->{_ordered_for_collapse};
1349 if (! $attrs->{_ordered_for_collapse}) {
1352 # instead of looping over ->next, use ->all in stealth mode
1353 # *without* calling a ->reset afterwards
1354 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1355 if (! $cursor->{_done}) {
1356 $rows = [ ($rows ? @$rows : ()), $cursor->all ];
1357 $cursor->{_done} = 1;
1362 if (! $did_fetch_all and ! @{$rows||[]} ) {
1363 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1364 $cursor ||= $self->cursor;
1365 if (scalar (my @r = $cursor->next) ) {
1370 return undef unless @{$rows||[]};
1372 # sanity check - people are too clever for their own good
1373 if ($attrs->{collapse} and my $aliastypes = $attrs->{_last_sqlmaker_alias_map} ) {
1375 my $multiplied_selectors;
1376 for my $sel_alias ( grep { $_ ne $attrs->{alias} } keys %{ $aliastypes->{selecting} } ) {
1378 $aliastypes->{multiplying}{$sel_alias}
1380 $aliastypes->{premultiplied}{$sel_alias}
1382 $multiplied_selectors->{$_} = 1 for values %{$aliastypes->{selecting}{$sel_alias}{-seen_columns}}
1386 for my $i (0 .. $#{$attrs->{as}} ) {
1387 my $sel = $attrs->{select}[$i];
1389 if (ref $sel eq 'SCALAR') {
1392 elsif( ref $sel eq 'REF' and ref $$sel eq 'ARRAY' ) {
1396 $self->throw_exception(
1397 'Result collapse not possible - selection from a has_many source redirected to the main object'
1398 ) if ($multiplied_selectors->{$sel} and $attrs->{as}[$i] !~ /\./);
1402 # hotspot - skip the setter
1403 my $res_class = $self->_result_class;
1405 my $inflator_cref = $self->{_result_inflator}{cref} ||= do {
1406 $res_class->can ('inflate_result')
1407 or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
1410 my $infmap = $attrs->{as};
1412 $self->{_result_inflator}{is_core_row} = ( (
1415 ( \&DBIx::Class::Row::inflate_result || die "No ::Row::inflate_result() - can't happen" )
1416 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_core_row};
1418 $self->{_result_inflator}{is_hri} = ( (
1419 ! $self->{_result_inflator}{is_core_row}
1421 $inflator_cref == \&DBIx::Class::ResultClass::HashRefInflator::inflate_result
1422 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_hri};
1425 if ($attrs->{_simple_passthrough_construction}) {
1426 # construct a much simpler array->hash folder for the one-table HRI cases right here
1427 if ($self->{_result_inflator}{is_hri}) {
1428 for my $r (@$rows) {
1429 $r = { map { $infmap->[$_] => $r->[$_] } 0..$#$infmap };
1432 # FIXME SUBOPTIMAL this is a very very very hot spot
1433 # while rather optimal we can *still* do much better, by
1434 # building a smarter Row::inflate_result(), and
1435 # switch to feeding it data via a much leaner interface
1437 # crude unscientific benchmarking indicated the shortcut eval is not worth it for
1438 # this particular resultset size
1439 elsif ( $self->{_result_inflator}{is_core_row} and @$rows < 60 ) {
1440 for my $r (@$rows) {
1441 $r = $inflator_cref->($res_class, $rsrc, { map { $infmap->[$_] => $r->[$_] } (0..$#$infmap) } );
1446 ( $self->{_result_inflator}{is_core_row}
1447 ? '$_ = $inflator_cref->($res_class, $rsrc, { %s }) for @$rows'
1448 # a custom inflator may be a multiplier/reductor - put it in direct list ctx
1449 : '@$rows = map { $inflator_cref->($res_class, $rsrc, { %s } ) } @$rows'
1451 ( join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap ) )
1457 $self->{_result_inflator}{is_hri} ? 'hri'
1458 : $self->{_result_inflator}{is_core_row} ? 'classic_pruning'
1459 : 'classic_nonpruning'
1462 unless( $self->{_row_parser}{$parser_type}{cref} ) {
1464 # $args and $attrs to _mk_row_parser are separated to delineate what is
1465 # core collapser stuff and what is dbic $rs specific
1466 $self->{_row_parser}{$parser_type}{src} = $rsrc->_mk_row_parser({
1467 inflate_map => $infmap,
1468 collapse => $attrs->{collapse},
1469 premultiplied => $attrs->{_main_source_premultiplied},
1470 hri_style => $self->{_result_inflator}{is_hri},
1471 prune_null_branches => $self->{_result_inflator}{is_hri} || $self->{_result_inflator}{is_core_row},
1474 $self->{_row_parser}{$parser_type}{cref} = do {
1475 package # hide form PAUSE
1476 DBIx::Class::__GENERATED_ROW_PARSER__;
1478 eval $self->{_row_parser}{$parser_type}{src};
1482 # this needs to close over the *current* cursor, hence why it is not cached above
1483 my $next_cref = ($did_fetch_all or ! $attrs->{collapse})
1486 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1487 my @r = $cursor->next or return;
1492 $self->{_row_parser}{$parser_type}{cref}->(
1495 ( $self->{_stashed_rows} = [] ),
1496 ( my $null_violations = {} ),
1499 $self->throw_exception(
1500 'Collapse aborted - the following columns are declared (or defaulted to) '
1501 . 'non-nullable within DBIC but NULLs were retrieved from storage: '
1502 . join( ', ', map { "'$infmap->[$_]'" } sort { $a <=> $b } keys %$null_violations )
1503 . ' within data row ' . dump_value({
1506 ( ! defined $self->{_stashed_rows}[0][$_] or length $self->{_stashed_rows}[0][$_] < 50 )
1507 ? $self->{_stashed_rows}[0][$_]
1508 : substr( $self->{_stashed_rows}[0][$_], 0, 50 ) . '...'
1509 } 0 .. $#{$self->{_stashed_rows}[0]}
1511 ) if keys %$null_violations;
1513 # simple in-place substitution, does not regrow $rows
1514 if ($self->{_result_inflator}{is_core_row}) {
1515 $_ = $inflator_cref->($res_class, $rsrc, @$_) for @$rows
1517 # Special-case multi-object HRI - there is no $inflator_cref pass at all
1518 elsif ( ! $self->{_result_inflator}{is_hri} ) {
1519 # the inflator may be a multiplier/reductor - put it in list ctx
1520 @$rows = map { $inflator_cref->($res_class, $rsrc, @$_) } @$rows;
1524 # The @$rows check seems odd at first - why wouldn't we want to warn
1525 # regardless? The issue is things like find() etc, where the user
1526 # *knows* only one result will come back. In these cases the ->all
1527 # is not a pessimization, but rather something we actually want
1529 'Unable to properly collapse has_many results in iterator mode due '
1530 . 'to order criteria - performed an eager cursor slurp underneath. '
1531 . 'Consider using ->all() instead'
1532 ) if ( ! $fetch_all and @$rows > 1 );
1537 =head2 result_source
1541 =item Arguments: L<$result_source?|DBIx::Class::ResultSource>
1543 =item Return Value: L<$result_source|DBIx::Class::ResultSource>
1547 An accessor for the primary ResultSource object from which this ResultSet
1554 =item Arguments: $result_class?
1556 =item Return Value: $result_class
1560 An accessor for the class to use when creating result objects. Defaults to
1561 C<< result_source->result_class >> - which in most cases is the name of the
1562 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1564 Note that changing the result_class will also remove any components
1565 that were originally loaded in the source class via
1566 L<load_components|Class::C3::Componentised/load_components( @comps )>.
1567 Any overloaded methods in the original source class will not run.
1572 my ($self, $result_class) = @_;
1573 if ($result_class) {
1575 # don't fire this for an object
1576 $self->ensure_class_loaded($result_class)
1577 unless ref($result_class);
1579 if ($self->get_cache) {
1580 carp_unique('Changing the result_class of a ResultSet instance with cached results is a noop - the cache contents will not be altered');
1582 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1583 elsif ($self->{cursor} && $self->{cursor}{_pos}) {
1584 $self->throw_exception('Changing the result_class of a ResultSet instance with an active cursor is not supported');
1587 $self->_result_class($result_class);
1589 delete $self->{_result_inflator};
1591 $self->_result_class;
1598 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1600 =item Return Value: $count
1604 Performs an SQL C<COUNT> with the same query as the resultset was built
1605 with to find the number of elements. Passing arguments is equivalent to
1606 C<< $rs->search ($cond, \%attrs)->count >>
1612 return $self->search(@_)->count if @_ and defined $_[0];
1613 return scalar @{ $self->get_cache } if $self->get_cache;
1615 my $attrs = { %{ $self->_resolved_attrs } };
1617 # this is a little optimization - it is faster to do the limit
1618 # adjustments in software, instead of a subquery
1619 my ($rows, $offset) = delete @{$attrs}{qw/rows offset/};
1622 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1623 $crs = $self->_count_subq_rs ($attrs);
1626 $crs = $self->_count_rs ($attrs);
1628 my $count = $crs->next;
1630 $count -= $offset if $offset;
1631 $count = $rows if $rows and $rows < $count;
1632 $count = 0 if ($count < 0);
1641 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1643 =item Return Value: L<$count_rs|DBIx::Class::ResultSetColumn>
1647 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1648 This can be very handy for subqueries:
1650 ->search( { amount => $some_rs->count_rs->as_query } )
1652 As with regular resultsets the SQL query will be executed only after
1653 the resultset is accessed via L</next> or L</all>. That would return
1654 the same single value obtainable via L</count>.
1660 return $self->search(@_)->count_rs if @_;
1662 # this may look like a lack of abstraction (count() does about the same)
1663 # but in fact an _rs *must* use a subquery for the limits, as the
1664 # software based limiting can not be ported if this $rs is to be used
1665 # in a subquery itself (i.e. ->as_query)
1666 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1667 return $self->_count_subq_rs($self->{_attrs});
1670 return $self->_count_rs($self->{_attrs});
1675 # returns a ResultSetColumn object tied to the count query
1678 my ($self, $attrs) = @_;
1680 my $rsrc = $self->result_source;
1682 my $tmp_attrs = { %$attrs };
1683 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1684 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1686 # overwrite the selector (supplied by the storage)
1687 $rsrc->resultset_class->new($rsrc, {
1689 select => $rsrc->schema->storage->_count_select ($rsrc, $attrs),
1691 })->get_column ('count');
1695 # same as above but uses a subquery
1697 sub _count_subq_rs {
1698 my ($self, $attrs) = @_;
1700 my $rsrc = $self->result_source;
1702 my $sub_attrs = { %$attrs };
1703 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1704 delete @{$sub_attrs}{qw/collapse columns as select order_by for/};
1706 # if we multi-prefetch we group_by something unique, as this is what we would
1707 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1708 if ( $attrs->{collapse} ) {
1709 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1710 $rsrc->_identifying_column_set || $self->throw_exception(
1711 'Unable to construct a unique group_by criteria properly collapsing the '
1712 . 'has_many prefetch before count()'
1717 # Calculate subquery selector
1718 if (my $g = $sub_attrs->{group_by}) {
1720 my $sql_maker = $rsrc->schema->storage->sql_maker;
1722 # necessary as the group_by may refer to aliased functions
1724 for my $sel (@{$attrs->{select}}) {
1725 $sel_index->{$sel->{-as}} = $sel
1726 if (ref $sel eq 'HASH' and $sel->{-as});
1729 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1730 # also look for named aggregates referred in the having clause
1731 # having often contains scalarrefs - thus parse it out entirely
1733 if ($attrs->{having}) {
1734 local $sql_maker->{having_bind};
1735 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1736 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1737 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1738 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1739 # if we don't unset it we screw up retarded but unfortunately working
1740 # 'MAX(foo.bar)' => { '>', 3 }
1741 $sql_maker->{name_sep} = '';
1744 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1746 my $having_sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1749 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1750 # and if all fails for an utterly naive quoted scalar-with-function
1751 while ($having_sql =~ /
1752 $rquote $sep $lquote (.+?) $rquote
1754 [\s,] \w+ \. (\w+) [\s,]
1756 [\s,] $lquote (.+?) $rquote [\s,]
1758 my $part = $1 || $2 || $3; # one of them matched if we got here
1759 unless ($seen_having{$part}++) {
1766 my $colpiece = $sel_index->{$_} || $_;
1768 # unqualify join-based group_by's. Arcane but possible query
1769 # also horrible horrible hack to alias a column (not a func.)
1770 # (probably need to introduce SQLA syntax)
1771 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1774 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1776 push @{$sub_attrs->{select}}, $colpiece;
1780 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1781 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1784 return $rsrc->resultset_class
1785 ->new ($rsrc, $sub_attrs)
1787 ->search ({}, { columns => { count => $rsrc->schema->storage->_count_select ($rsrc, $attrs) } })
1788 ->get_column ('count');
1792 =head2 count_literal
1794 B<CAVEAT>: C<count_literal> is provided for Class::DBI compatibility and
1795 should only be used in that context. See L</search_literal> for further info.
1799 =item Arguments: $sql_fragment, @standalone_bind_values
1801 =item Return Value: $count
1805 Counts the results in a literal query. Equivalent to calling L</search_literal>
1806 with the passed arguments, then L</count>.
1810 sub count_literal :DBIC_method_is_indirect_sugar {
1811 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1812 shift->search_literal(@_)->count
1819 =item Arguments: none
1821 =item Return Value: L<@result_objs|DBIx::Class::Manual::ResultClass>
1825 Returns all elements in the resultset.
1832 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1835 delete @{$self}{qw/_stashed_rows _stashed_results/};
1837 if (my $c = $self->get_cache) {
1841 $self->cursor->reset;
1843 my $objs = $self->_construct_results('fetch_all') || [];
1845 $self->set_cache($objs) if $self->{attrs}{cache};
1854 =item Arguments: none
1856 =item Return Value: $self
1860 Resets the resultset's cursor, so you can iterate through the elements again.
1861 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1869 delete @{$self}{qw/_stashed_rows _stashed_results/};
1870 $self->{all_cache_position} = 0;
1871 $self->cursor->reset;
1879 =item Arguments: none
1881 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1885 L<Resets|/reset> the resultset (causing a fresh query to storage) and returns
1886 an object for the first result (or C<undef> if the resultset is empty).
1890 sub first :DBIC_method_is_indirect_sugar {
1891 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1892 return $_[0]->reset->next;
1898 # Determines whether and what type of subquery is required for the $rs operation.
1899 # If grouping is necessary either supplies its own, or verifies the current one
1900 # After all is done delegates to the proper storage method.
1902 sub _rs_update_delete {
1903 my ($self, $op, $values) = @_;
1905 my $rsrc = $self->result_source;
1906 my $storage = $rsrc->schema->storage;
1908 my $attrs = { %{$self->_resolved_attrs} };
1910 my $join_classifications;
1911 my ($existing_group_by) = delete @{$attrs}{qw(group_by _grouped_by_distinct)};
1913 # do we need a subquery for any reason?
1915 defined $existing_group_by
1917 # if {from} is unparseable wrap a subq
1918 ref($attrs->{from}) ne 'ARRAY'
1920 # limits call for a subq
1921 $self->_has_resolved_attr(qw/rows offset/)
1924 # simplify the joinmap, so we can further decide if a subq is necessary
1925 if (!$needs_subq and @{$attrs->{from}} > 1) {
1927 ($attrs->{from}, $join_classifications) =
1928 $storage->_prune_unused_joins ($attrs);
1930 # any non-pruneable non-local restricting joins imply subq
1931 $needs_subq = grep { $_ ne $attrs->{alias} } keys %{ $join_classifications->{restricting} || {} };
1934 # check if the head is composite (by now all joins are thrown out unless $needs_subq)
1936 (ref $attrs->{from}[0]) ne 'HASH'
1938 ref $attrs->{from}[0]{ $attrs->{from}[0]{-alias} }
1942 # do we need anything like a subquery?
1943 if (! $needs_subq) {
1944 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1945 # a condition containing 'me' or other table prefixes will not work
1946 # at all. Tell SQLMaker to dequalify idents via a gross hack.
1948 my $sqla = $rsrc->schema->storage->sql_maker;
1949 local $sqla->{_dequalify_idents} = 1;
1950 \[ $sqla->_recurse_where($self->{cond}) ];
1954 # we got this far - means it is time to wrap a subquery
1955 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1957 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1963 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1964 delete $attrs->{$_} for qw/select as collapse/;
1965 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1967 # this will be consumed by the pruner waaaaay down the stack
1968 $attrs->{_force_prune_multiplying_joins} = 1;
1970 my $subrs = (ref $self)->new($rsrc, $attrs);
1972 if (@$idcols == 1) {
1973 $cond = { $idcols->[0] => { -in => $subrs->as_query } };
1975 elsif ($storage->_use_multicolumn_in) {
1976 # no syntax for calling this properly yet
1977 # !!! EXPERIMENTAL API !!! WILL CHANGE !!!
1978 $cond = $storage->sql_maker->_where_op_multicolumn_in (
1979 $idcols, # how do I convey a list of idents...? can binds reside on lhs?
1984 # if all else fails - get all primary keys and operate over a ORed set
1985 # wrap in a transaction for consistency
1986 # this is where the group_by/multiplication starts to matter
1990 # we do not need to check pre-multipliers, since if the premulti is there, its
1991 # parent (who is multi) will be there too
1992 keys %{ $join_classifications->{multiplying} || {} }
1994 # make sure if there is a supplied group_by it matches the columns compiled above
1995 # perfectly. Anything else can not be sanely executed on most databases so croak
1996 # right then and there
1997 if ($existing_group_by) {
1998 my @current_group_by = map
1999 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
2004 join ("\x00", sort @current_group_by)
2006 join ("\x00", sort @{$attrs->{columns}} )
2008 $self->throw_exception (
2009 "You have just attempted a $op operation on a resultset which does group_by"
2010 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
2011 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
2012 . ' kind of queries. Please retry the operation with a modified group_by or'
2013 . ' without using one at all.'
2018 $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
2021 $guard = $storage->txn_scope_guard;
2023 for my $row ($subrs->cursor->all) {
2025 { $idcols->[$_] => $row->[$_] }
2032 my $res = $cond ? $storage->$op (
2034 $op eq 'update' ? $values : (),
2038 $guard->commit if $guard;
2047 =item Arguments: \%values
2049 =item Return Value: $underlying_storage_rv
2053 Sets the specified columns in the resultset to the supplied values in a
2054 single query. Note that this will not run any accessor/set_column/update
2055 triggers, nor will it update any result object instances derived from this
2056 resultset (this includes the contents of the L<resultset cache|/set_cache>
2057 if any). See L</update_all> if you need to execute any on-update
2058 triggers or cascades defined either by you or a
2059 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2061 The return value is a pass through of what the underlying
2062 storage backend returned, and may vary. See L<DBI/execute> for the most
2067 Note that L</update> does not process/deflate any of the values passed in.
2068 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
2069 ensure manually that any value passed to this method will stringify to
2070 something the RDBMS knows how to deal with. A notable example is the
2071 handling of L<DateTime> objects, for more info see:
2072 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
2077 my ($self, $values) = @_;
2078 $self->throw_exception('Values for update must be a hash')
2079 unless ref $values eq 'HASH';
2081 return $self->_rs_update_delete ('update', $values);
2088 =item Arguments: \%values
2090 =item Return Value: 1
2094 Fetches all objects and updates them one at a time via
2095 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
2096 triggers, while L</update> will not.
2101 my ($self, $values) = @_;
2102 $self->throw_exception('Values for update_all must be a hash')
2103 unless ref $values eq 'HASH';
2105 my $guard = $self->result_source->schema->txn_scope_guard;
2106 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
2115 =item Arguments: none
2117 =item Return Value: $underlying_storage_rv
2121 Deletes the rows matching this resultset in a single query. Note that this
2122 will not run any delete triggers, nor will it alter the
2123 L<in_storage|DBIx::Class::Row/in_storage> status of any result object instances
2124 derived from this resultset (this includes the contents of the
2125 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
2126 execute any on-delete triggers or cascades defined either by you or a
2127 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2129 The return value is a pass through of what the underlying storage backend
2130 returned, and may vary. See L<DBI/execute> for the most common case.
2136 $self->throw_exception('delete does not accept any arguments')
2139 return $self->_rs_update_delete ('delete');
2146 =item Arguments: none
2148 =item Return Value: 1
2152 Fetches all objects and deletes them one at a time via
2153 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2154 triggers, while L</delete> will not.
2160 $self->throw_exception('delete_all does not accept any arguments')
2163 my $guard = $self->result_source->schema->txn_scope_guard;
2164 $_->delete for $self->all;
2173 =item Arguments: [ \@column_list, \@row_values+ ] | [ \%col_data+ ]
2175 =item Return Value: L<\@result_objects|DBIx::Class::Manual::ResultClass> (scalar context) | L<@result_objects|DBIx::Class::Manual::ResultClass> (list context)
2179 Accepts either an arrayref of hashrefs or alternatively an arrayref of
2186 The context of this method call has an important effect on what is
2187 submitted to storage. In void context data is fed directly to fastpath
2188 insertion routines provided by the underlying storage (most often
2189 L<DBI/execute_for_fetch>), bypassing the L<new|DBIx::Class::Row/new> and
2190 L<insert|DBIx::Class::Row/insert> calls on the
2191 L<Result|DBIx::Class::Manual::ResultClass> class, including any
2192 augmentation of these methods provided by components. For example if you
2193 are using something like L<DBIx::Class::UUIDColumns> to create primary
2194 keys for you, you will find that your PKs are empty. In this case you
2195 will have to explicitly force scalar or list context in order to create
2200 In non-void (scalar or list) context, this method is simply a wrapper
2201 for L</create>. Depending on list or scalar context either a list of
2202 L<Result|DBIx::Class::Manual::ResultClass> objects or an arrayref
2203 containing these objects is returned.
2205 When supplying data in "arrayref of arrayrefs" invocation style, the
2206 first element should be a list of column names and each subsequent
2207 element should be a data value in the earlier specified column order.
2210 $schema->resultset("Artist")->populate([
2211 [ qw( artistid name ) ],
2212 [ 100, 'A Formally Unknown Singer' ],
2213 [ 101, 'A singer that jumped the shark two albums ago' ],
2214 [ 102, 'An actually cool singer' ],
2217 For the arrayref of hashrefs style each hashref should be a structure
2218 suitable for passing to L</create>. Multi-create is also permitted with
2221 $schema->resultset("Artist")->populate([
2222 { artistid => 4, name => 'Manufactured Crap', cds => [
2223 { title => 'My First CD', year => 2006 },
2224 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2227 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2228 { title => 'My parents sold me to a record company', year => 2005 },
2229 { title => 'Why Am I So Ugly?', year => 2006 },
2230 { title => 'I Got Surgery and am now Popular', year => 2007 }
2235 If you attempt a void-context multi-create as in the example above (each
2236 Artist also has the related list of CDs), and B<do not> supply the
2237 necessary autoinc foreign key information, this method will proxy to the
2238 less efficient L</create>, and then throw the Result objects away. In this
2239 case there are obviously no benefits to using this method over L</create>.
2246 # this is naive and just a quick check
2247 # the types will need to be checked more thoroughly when the
2248 # multi-source populate gets added
2250 ref $_[0] eq 'ARRAY'
2252 ( @{$_[0]} or return )
2254 ( ref $_[0][0] eq 'HASH' or ref $_[0][0] eq 'ARRAY' )
2257 ) or $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2259 # FIXME - no cref handling
2260 # At this point assume either hashes or arrays
2262 my $rsrc = $self->result_source;
2263 my $storage = $rsrc->schema->storage;
2265 if(defined wantarray) {
2266 my (@results, $guard);
2268 if (ref $data->[0] eq 'ARRAY') {
2269 # column names only, nothing to do
2270 return if @$data == 1;
2272 $guard = $storage->txn_scope_guard
2276 { my $vals = $_; $self->new_result({ map { $data->[0][$_] => $vals->[$_] } 0..$#{$data->[0]} })->insert }
2277 @{$data}[1 .. $#$data]
2282 $guard = $storage->txn_scope_guard
2285 @results = map { $self->new_result($_)->insert } @$data;
2288 $guard->commit if $guard;
2289 return wantarray ? @results : \@results;
2292 # we have to deal with *possibly incomplete* related data
2293 # this means we have to walk the data structure twice
2294 # whether we want this or not
2295 # jnap, I hate you ;)
2296 my $rel_info = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2298 my ($colinfo, $colnames, $slices_with_rels);
2302 for my $i (0 .. $#$data) {
2304 my $current_slice_seen_rel_infos;
2306 ### Determine/Supplement collists
2307 ### BEWARE - This is a hot piece of code, a lot of weird idioms were used
2308 if( ref $data->[$i] eq 'ARRAY' ) {
2310 # positional(!) explicit column list
2312 # column names only, nothing to do
2313 return if @$data == 1;
2315 $colinfo->{$data->[0][$_]} = { pos => $_, name => $data->[0][$_] } and push @$colnames, $data->[0][$_]
2316 for 0 .. $#{$data->[0]};
2323 for (values %$colinfo) {
2324 if ($_->{is_rel} ||= (
2325 $rel_info->{$_->{name}}
2328 ref $data->[$i][$_->{pos}] eq 'ARRAY'
2330 ref $data->[$i][$_->{pos}] eq 'HASH'
2333 defined blessed $data->[$i][$_->{pos}]
2335 $data->[$i][$_->{pos}]->isa(
2336 $DBIx::Class::ResultSource::__expected_result_class_isa
2340 msg => 'Global $DBIx::Class::ResultSource::__expected_result_class_isa unexpectedly unset...'
2349 # moar sanity check... sigh
2350 for ( ref $data->[$i][$_->{pos}] eq 'ARRAY' ? @{$data->[$i][$_->{pos}]} : $data->[$i][$_->{pos}] ) {
2355 $DBIx::Class::ResultSource::__expected_result_class_isa
2359 msg => 'Global $DBIx::Class::ResultSource::__expected_result_class_isa unexpectedly unset...'
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, $rel_info->{$_->{name}};
2373 if ($current_slice_seen_rel_infos) {
2374 push @$slices_with_rels, { map { $colnames->[$_] => $data->[$i][$_] } 0 .. $#$colnames };
2376 # this is needed further down to decide whether or not to fallback to create()
2377 $colinfo->{$colnames->[$_]}{seen_null} ||= ! defined $data->[$i][$_]
2378 for 0 .. $#$colnames;
2381 elsif( ref $data->[$i] eq 'HASH' ) {
2383 for ( sort keys %{$data->[$i]} ) {
2385 $colinfo->{$_} ||= do {
2387 $self->throw_exception("Column '$_' must be present in supplied explicit column list")
2388 if $data_start; # it will be 0 on AoH, 1 on AoA
2390 push @$colnames, $_;
2393 { pos => $#$colnames, name => $_ }
2396 if ($colinfo->{$_}{is_rel} ||= (
2400 ref $data->[$i]{$_} eq 'ARRAY'
2402 ref $data->[$i]{$_} eq 'HASH'
2405 defined blessed $data->[$i]{$_}
2407 $data->[$i]{$_}->isa(
2408 $DBIx::Class::ResultSource::__expected_result_class_isa
2412 msg => 'Global $DBIx::Class::ResultSource::__expected_result_class_isa unexpectedly unset...'
2421 # moar sanity check... sigh
2422 for ( ref $data->[$i]{$_} eq 'ARRAY' ? @{$data->[$i]{$_}} : $data->[$i]{$_} ) {
2427 $DBIx::Class::ResultSource::__expected_result_class_isa
2431 msg => 'Global $DBIx::Class::ResultSource::__expected_result_class_isa unexpectedly unset...'
2435 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2436 return my $throwaway = $self->populate(@_);
2440 push @$current_slice_seen_rel_infos, $rel_info->{$_};
2444 if ($current_slice_seen_rel_infos) {
2445 push @$slices_with_rels, $data->[$i];
2447 # this is needed further down to decide whether or not to fallback to create()
2448 $colinfo->{$_}{seen_null} ||= ! defined $data->[$i]{$_}
2449 for keys %{$data->[$i]};
2453 $self->throw_exception('Unexpected populate() data structure member type: ' . ref $data->[$i] );
2457 { $_->{attrs}{is_depends_on} }
2458 @{ $current_slice_seen_rel_infos || [] }
2460 carp_unique("Fast-path populate() of belongs_to relationship data is not possible - falling back to regular create()");
2461 return my $throwaway = $self->populate(@_);
2465 if( $slices_with_rels ) {
2467 # need to exclude the rel "columns"
2468 $colnames = [ grep { ! $colinfo->{$_}{is_rel} } @$colnames ];
2470 # extra sanity check - ensure the main source is in fact identifiable
2471 # the localizing of nullability is insane, but oh well... the use-case is legit
2472 my $ci = $rsrc->columns_info($colnames);
2474 $ci->{$_} = { %{$ci->{$_}}, is_nullable => 0 }
2475 for grep { ! $colinfo->{$_}{seen_null} } keys %$ci;
2477 unless( $rsrc->_identifying_column_set($ci) ) {
2478 carp_unique("Fast-path populate() of non-uniquely identifiable rows with related data is not possible - falling back to regular create()");
2479 return my $throwaway = $self->populate(@_);
2483 ### inherit the data locked in the conditions of the resultset
2484 my ($rs_data) = $self->_merge_with_rscond({});
2485 delete @{$rs_data}{@$colnames}; # passed-in stuff takes precedence
2487 # if anything left - decompose rs_data
2489 if (keys %$rs_data) {
2490 push @$rs_data_vals, $rs_data->{$_}
2491 for sort keys %$rs_data;
2496 $guard = $storage->txn_scope_guard
2497 if $slices_with_rels;
2499 ### main source data
2500 # FIXME - need to switch entirely to a coderef-based thing,
2501 # so that large sets aren't copied several times... I think
2502 $storage->_insert_bulk(
2504 [ @$colnames, sort keys %$rs_data ],
2506 ref $data->[$_] eq 'ARRAY'
2508 $slices_with_rels ? [ @{$data->[$_]}[0..$#$colnames], @{$rs_data_vals||[]} ] # the collist changed
2509 : $rs_data_vals ? [ @{$data->[$_]}, @$rs_data_vals ]
2512 : [ @{$data->[$_]}{@$colnames}, @{$rs_data_vals||[]} ]
2513 } $data_start .. $#$data ],
2516 ### do the children relationships
2517 if ( $slices_with_rels ) {
2518 my @rels = grep { $colinfo->{$_}{is_rel} } keys %$colinfo
2519 or die 'wtf... please report a bug with DBIC_TRACE=1 output (stacktrace)';
2521 for my $sl (@$slices_with_rels) {
2523 my ($main_proto, $main_proto_rs);
2524 for my $rel (@rels) {
2525 next unless defined $sl->{$rel};
2529 (map { $_ => $sl->{$_} } @$colnames),
2532 unless (defined $colinfo->{$rel}{rs}) {
2534 $colinfo->{$rel}{rs} = $rsrc->related_source($rel)->resultset;
2536 $colinfo->{$rel}{fk_map} = { reverse %{ $rsrc->resolve_relationship_condition(
2539 # an API where these are optional would be too cumbersome,
2540 # instead always pass in some dummy values
2542 )->{identity_map} || {} } };
2546 $colinfo->{$rel}{rs}->search({ map # only so that we inherit them values properly, no actual search
2549 ( $main_proto_rs ||= $rsrc->resultset->search($main_proto) )
2550 ->get_column( $colinfo->{$rel}{fk_map}{$_} )
2554 keys %{$colinfo->{$rel}{fk_map}}
2555 })->populate( ref $sl->{$rel} eq 'ARRAY' ? $sl->{$rel} : [ $sl->{$rel} ] );
2562 $guard->commit if $guard;
2569 =item Arguments: none
2571 =item Return Value: L<$pager|Data::Page>
2575 Returns a L<Data::Page> object for the current resultset. Only makes
2576 sense for queries with a C<page> attribute.
2578 To get the full count of entries for a paged resultset, call
2579 C<total_entries> on the L<Data::Page> object.
2586 return $self->{pager} if $self->{pager};
2588 my $attrs = $self->{attrs};
2589 if (!defined $attrs->{page}) {
2590 $self->throw_exception("Can't create pager for non-paged rs");
2592 elsif ($attrs->{page} <= 0) {
2593 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2595 $attrs->{rows} ||= 10;
2597 # throw away the paging flags and re-run the count (possibly
2598 # with a subselect) to get the real total count
2599 my $count_attrs = { %$attrs };
2600 delete @{$count_attrs}{qw/rows offset page pager/};
2602 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2604 require DBIx::Class::ResultSet::Pager;
2605 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2606 sub { $total_rs->count }, #lazy-get the total
2608 $self->{attrs}{page},
2616 =item Arguments: $page_number
2618 =item Return Value: L<$resultset|/search>
2622 Returns a resultset for the $page_number page of the resultset on which page
2623 is called, where each page contains a number of rows equal to the 'rows'
2624 attribute set on the resultset (10 by default).
2629 my ($self, $page) = @_;
2630 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2637 =item Arguments: \%col_data
2639 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2643 Creates a new result object in the resultset's result class and returns
2644 it. The row is not inserted into the database at this point, call
2645 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2646 will tell you whether the result object has been inserted or not.
2648 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2653 my ($self, $values) = @_;
2655 $self->throw_exception( "Result object instantiation requires a single hashref argument" )
2656 if @_ > 2 or ref $values ne 'HASH';
2658 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2660 my $new = $self->result_class->new({
2662 ( @$cols_from_relations
2663 ? (-cols_from_relations => $cols_from_relations)
2666 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2670 reftype($new) eq 'HASH'
2676 carp_unique (sprintf (
2677 "%s->new returned a blessed empty hashref - a strong indicator something is wrong with its inheritance chain",
2678 $self->result_class,
2685 # _merge_with_rscond
2687 # Takes a simple hash of K/V data and returns its copy merged with the
2688 # condition already present on the resultset. Additionally returns an
2689 # arrayref of value/condition names, which were inferred from related
2690 # objects (this is needed for in-memory related objects)
2691 sub _merge_with_rscond {
2692 my ($self, $data) = @_;
2694 my ($implied_data, @cols_from_relations);
2696 my $alias = $self->{attrs}{alias};
2698 if (! defined $self->{cond}) {
2699 # just massage $data below
2701 elsif ($self->{cond} eq UNRESOLVABLE_CONDITION) {
2702 $implied_data = $self->{attrs}{related_objects}; # nothing might have been inserted yet
2703 @cols_from_relations = keys %{ $implied_data || {} };
2706 my $eqs = extract_equality_conditions( $self->{cond}, 'consider_nulls' );
2707 $implied_data = { map {
2708 ( ($eqs->{$_}||'') eq UNRESOLVABLE_CONDITION ) ? () : ( $_ => $eqs->{$_} )
2714 { %{ $self->_remove_alias($_, $alias) } }
2715 # precedence must be given to passed values over values inherited from
2716 # the cond, so the order here is important.
2717 ( $implied_data||(), $data)
2719 \@cols_from_relations
2723 # _has_resolved_attr
2725 # determines if the resultset defines at least one
2726 # of the attributes supplied
2728 # used to determine if a subquery is necessary
2730 # supports some virtual attributes:
2732 # This will scan for any joins being present on the resultset.
2733 # It is not a mere key-search but a deep inspection of {from}
2736 sub _has_resolved_attr {
2737 my ($self, @attr_names) = @_;
2739 my $attrs = $self->_resolved_attrs;
2743 for my $n (@attr_names) {
2744 if (grep { $n eq $_ } (qw/-join/) ) {
2745 $extra_checks{$n}++;
2749 my $attr = $attrs->{$n};
2751 next if not defined $attr;
2753 if (ref $attr eq 'HASH') {
2754 return 1 if keys %$attr;
2756 elsif (ref $attr eq 'ARRAY') {
2764 # a resolved join is expressed as a multi-level from
2766 $extra_checks{-join}
2768 ref $attrs->{from} eq 'ARRAY'
2770 @{$attrs->{from}} > 1
2778 # Remove the specified alias from the specified query hash. A copy is made so
2779 # the original query is not modified.
2782 my ($self, $query, $alias) = @_;
2784 my %orig = %{ $query || {} };
2787 foreach my $key (keys %orig) {
2789 $unaliased{$key} = $orig{$key};
2792 $unaliased{$1} = $orig{$key}
2793 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2803 =item Arguments: none
2805 =item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
2809 Returns the SQL query and bind vars associated with the invocant.
2811 This is generally used as the RHS for a subquery.
2818 my $attrs = { %{ $self->_resolved_attrs } };
2820 my $aq = $self->result_source->schema->storage->_select_args_to_query (
2821 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
2831 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2833 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2837 my $artist = $schema->resultset('Artist')->find_or_new(
2838 { artist => 'fred' }, { key => 'artists' });
2840 $cd->cd_to_producer->find_or_new({ producer => $producer },
2841 { key => 'primary' });
2843 Find an existing record from this resultset using L</find>. if none exists,
2844 instantiate a new result object and return it. The object will not be saved
2845 into your storage until you call L<DBIx::Class::Row/insert> on it.
2847 You most likely want this method when looking for existing rows using a unique
2848 constraint that is not the primary key, or looking for related rows.
2850 If you want objects to be saved immediately, use L</find_or_create> instead.
2852 B<Note>: Make sure to read the documentation of L</find> and understand the
2853 significance of the C<key> attribute, as its lack may skew your search, and
2854 subsequently result in spurious new objects.
2856 B<Note>: Take care when using C<find_or_new> with a table having
2857 columns with default values that you intend to be automatically
2858 supplied by the database (e.g. an auto_increment primary key column).
2859 In normal usage, the value of such columns should NOT be included at
2860 all in the call to C<find_or_new>, even when set to C<undef>.
2866 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
2867 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2868 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2871 return $self->new_result($hash);
2878 =item Arguments: \%col_data
2880 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2884 Attempt to create a single new row or a row with multiple related rows
2885 in the table represented by the resultset (and related tables). This
2886 will not check for duplicate rows before inserting, use
2887 L</find_or_create> to do that.
2889 To create one row for this resultset, pass a hashref of key/value
2890 pairs representing the columns of the table and the values you wish to
2891 store. If the appropriate relationships are set up, foreign key fields
2892 can also be passed an object representing the foreign row, and the
2893 value will be set to its primary key.
2895 To create related objects, pass a hashref of related-object column values
2896 B<keyed on the relationship name>. If the relationship is of type C<multi>
2897 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2898 The process will correctly identify columns holding foreign keys, and will
2899 transparently populate them from the keys of the corresponding relation.
2900 This can be applied recursively, and will work correctly for a structure
2901 with an arbitrary depth and width, as long as the relationships actually
2902 exists and the correct column data has been supplied.
2904 Instead of hashrefs of plain related data (key/value pairs), you may
2905 also pass new or inserted objects. New objects (not inserted yet, see
2906 L</new_result>), will be inserted into their appropriate tables.
2908 Effectively a shortcut for C<< ->new_result(\%col_data)->insert >>.
2910 Example of creating a new row.
2912 $person_rs->create({
2913 name=>"Some Person",
2914 email=>"somebody@someplace.com"
2917 Example of creating a new row and also creating rows in a related C<has_many>
2918 or C<has_one> resultset. Note Arrayref.
2921 { artistid => 4, name => 'Manufactured Crap', cds => [
2922 { title => 'My First CD', year => 2006 },
2923 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2928 Example of creating a new row and also creating a row in a related
2929 C<belongs_to> resultset. Note Hashref.
2932 title=>"Music for Silly Walks",
2935 name=>"Silly Musician",
2943 When subclassing ResultSet never attempt to override this method. Since
2944 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2945 lot of the internals simply never call it, so your override will be
2946 bypassed more often than not. Override either L<DBIx::Class::Row/new>
2947 or L<DBIx::Class::Row/insert> depending on how early in the
2948 L</create> process you need to intervene. See also warning pertaining to
2955 sub create :DBIC_method_is_indirect_sugar {
2956 #my ($self, $col_data) = @_;
2957 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
2958 return shift->new_result(shift)->insert;
2961 =head2 find_or_create
2965 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2967 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2971 $cd->cd_to_producer->find_or_create({ producer => $producer },
2972 { key => 'primary' });
2974 Tries to find a record based on its primary key or unique constraints; if none
2975 is found, creates one and returns that instead.
2977 my $cd = $schema->resultset('CD')->find_or_create({
2979 artist => 'Massive Attack',
2980 title => 'Mezzanine',
2984 Also takes an optional C<key> attribute, to search by a specific key or unique
2985 constraint. For example:
2987 my $cd = $schema->resultset('CD')->find_or_create(
2989 artist => 'Massive Attack',
2990 title => 'Mezzanine',
2992 { key => 'cd_artist_title' }
2995 B<Note>: Make sure to read the documentation of L</find> and understand the
2996 significance of the C<key> attribute, as its lack may skew your search, and
2997 subsequently result in spurious row creation.
2999 B<Note>: Because find_or_create() reads from the database and then
3000 possibly inserts based on the result, this method is subject to a race
3001 condition. Another process could create a record in the table after
3002 the find has completed and before the create has started. To avoid
3003 this problem, use find_or_create() inside a transaction.
3005 B<Note>: Take care when using C<find_or_create> with a table having
3006 columns with default values that you intend to be automatically
3007 supplied by the database (e.g. an auto_increment primary key column).
3008 In normal usage, the value of such columns should NOT be included at
3009 all in the call to C<find_or_create>, even when set to C<undef>.
3011 See also L</find> and L</update_or_create>. For information on how to declare
3012 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
3014 If you need to know if an existing row was found or a new one created use
3015 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
3016 to call L<DBIx::Class::Row/insert> to save the newly created row to the
3019 my $cd = $schema->resultset('CD')->find_or_new({
3021 artist => 'Massive Attack',
3022 title => 'Mezzanine',
3026 if( !$cd->in_storage ) {
3033 sub find_or_create {
3035 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
3036 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
3037 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
3040 return $self->new_result($hash)->insert;
3043 =head2 update_or_create
3047 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
3049 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
3053 $resultset->update_or_create({ col => $val, ... });
3055 Like L</find_or_create>, but if a row is found it is immediately updated via
3056 C<< $found_row->update (\%col_data) >>.
3059 Takes an optional C<key> attribute to search on a specific unique constraint.
3062 # In your application
3063 my $cd = $schema->resultset('CD')->update_or_create(
3065 artist => 'Massive Attack',
3066 title => 'Mezzanine',
3069 { key => 'cd_artist_title' }
3072 $cd->cd_to_producer->update_or_create({
3073 producer => $producer,
3079 B<Note>: Make sure to read the documentation of L</find> and understand the
3080 significance of the C<key> attribute, as its lack may skew your search, and
3081 subsequently result in spurious row creation.
3083 B<Note>: Take care when using C<update_or_create> with a table having
3084 columns with default values that you intend to be automatically
3085 supplied by the database (e.g. an auto_increment primary key column).
3086 In normal usage, the value of such columns should NOT be included at
3087 all in the call to C<update_or_create>, even when set to C<undef>.
3089 See also L</find> and L</find_or_create>. For information on how to declare
3090 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
3092 If you need to know if an existing row was updated or a new one created use
3093 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
3094 to call L<DBIx::Class::Row/insert> to save the newly created row to the
3099 sub update_or_create {
3101 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
3102 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3104 my $row = $self->find($cond, $attrs);
3106 $row->update($cond);
3110 return $self->new_result($cond)->insert;
3113 =head2 update_or_new
3117 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
3119 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
3123 $resultset->update_or_new({ col => $val, ... });
3125 Like L</find_or_new> but if a row is found it is immediately updated via
3126 C<< $found_row->update (\%col_data) >>.
3130 # In your application
3131 my $cd = $schema->resultset('CD')->update_or_new(
3133 artist => 'Massive Attack',
3134 title => 'Mezzanine',
3137 { key => 'cd_artist_title' }
3140 if ($cd->in_storage) {
3141 # the cd was updated
3144 # the cd is not yet in the database, let's insert it
3148 B<Note>: Make sure to read the documentation of L</find> and understand the
3149 significance of the C<key> attribute, as its lack may skew your search, and
3150 subsequently result in spurious new objects.
3152 B<Note>: Take care when using C<update_or_new> with a table having
3153 columns with default values that you intend to be automatically
3154 supplied by the database (e.g. an auto_increment primary key column).
3155 In normal usage, the value of such columns should NOT be included at
3156 all in the call to C<update_or_new>, even when set to C<undef>.
3158 See also L</find>, L</find_or_create> and L</find_or_new>.
3164 my $attrs = ( @_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {} );
3165 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3167 my $row = $self->find( $cond, $attrs );
3168 if ( defined $row ) {
3169 $row->update($cond);
3173 return $self->new_result($cond);
3180 =item Arguments: none
3182 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass> | undef
3186 Gets the contents of the cache for the resultset, if the cache is set.
3188 The cache is populated either by using the L</prefetch> attribute to
3189 L</search> or by calling L</set_cache>.
3201 =item Arguments: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3203 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3207 Sets the contents of the cache for the resultset. Expects an arrayref
3208 of objects of the same class as those produced by the resultset. Note that
3209 if the cache is set, the resultset will return the cached objects rather
3210 than re-querying the database even if the cache attr is not set.
3212 The contents of the cache can also be populated by using the
3213 L</prefetch> attribute to L</search>.
3218 my ( $self, $data ) = @_;
3219 $self->throw_exception("set_cache requires an arrayref")
3220 if defined($data) && (ref $data ne 'ARRAY');
3221 $self->{all_cache} = $data;
3228 =item Arguments: none
3230 =item Return Value: undef
3234 Clears the cache for the resultset.
3239 shift->set_cache(undef);
3246 =item Arguments: none
3248 =item Return Value: true, if the resultset has been paginated
3256 return !!$self->{attrs}{page};
3263 =item Arguments: none
3265 =item Return Value: true, if the resultset has been ordered with C<order_by>.
3273 return scalar $self->result_source->schema->storage->_extract_order_criteria($self->{attrs}{order_by});
3276 =head2 related_resultset
3280 =item Arguments: $rel_name
3282 =item Return Value: L<$resultset|/search>
3286 Returns a related resultset for the supplied relationship name.
3288 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
3292 sub related_resultset {
3293 $_[0]->throw_exception(
3294 'Extra arguments to $rs->related_resultset() were always quietly '
3295 . 'discarded without consideration, you need to switch to '
3296 . '...->related_resultset( $relname )->search_rs( $search, $args ) instead.'
3299 return $_[0]->{related_resultsets}{$_[1]}
3300 if defined $_[0]->{related_resultsets}{$_[1]};
3302 my ($self, $rel) = @_;
3304 return $self->{related_resultsets}{$rel} = do {
3305 my $rsrc = $self->result_source;
3306 my $rel_info = $rsrc->relationship_info($rel);
3308 $self->throw_exception(
3309 "search_related: result source '" . $rsrc->source_name .
3310 "' has no such relationship $rel")
3313 my $attrs = $self->_chain_relationship($rel);
3315 # Previously this atribute was deleted (instead of being set as it is now)
3316 # Doing so seems to be harmless in all available test permutations
3317 # See also 01d59a6a6 and mst's comment below
3319 $attrs->{alias} = $rsrc->schema->storage->relname_to_table_alias(
3321 $attrs->{seen_join}{$rel}
3324 # since this is search_related, and we already slid the select window inwards
3325 # (the select/as attrs were deleted in the beginning), we need to flip all
3326 # left joins to inner, so we get the expected results
3328 # The DBIC relationship chaining implementation is pretty simple - every
3329 # new related_relationship is pushed onto the {from} stack, and the {select}
3330 # window simply slides further in. This means that when we count somewhere
3331 # in the middle, we got to make sure that everything in the join chain is an
3332 # actual inner join, otherwise the count will come back with unpredictable
3333 # results (a resultset may be generated with _some_ rows regardless of if
3334 # the relation which the $rs currently selects has rows or not). E.g.
3335 # $artist_rs->cds->count - normally generates:
3336 # SELECT COUNT( * ) FROM artist me LEFT JOIN cd cds ON cds.artist = me.artistid
3337 # which actually returns the number of artists * (number of cds || 1)
3339 # So what we do here is crawl {from}, determine if the current alias is at
3340 # the top of the stack, and if not - make sure the chain is inner-joined down
3343 my $switch_branch = find_join_path_to_alias(
3348 if ( @{ $switch_branch || [] } ) {
3350 # So it looks like we will have to switch some stuff around.
3351 # local() is useless here as we will be leaving the scope
3352 # anyway, and deep cloning is just too fucking expensive
3353 # So replace the first hashref in the node arrayref manually
3354 my @new_from = $attrs->{from}[0];
3355 my $sw_idx = { map { (values %$_), 1 } @$switch_branch }; #there's one k/v per join-path
3357 for my $j ( @{$attrs->{from}}[ 1 .. $#{$attrs->{from}} ] ) {
3358 my $jalias = $j->[0]{-alias};
3360 if ($sw_idx->{$jalias}) {
3361 my %attrs = %{$j->[0]};
3362 delete $attrs{-join_type};
3373 $attrs->{from} = \@new_from;
3377 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3378 delete $attrs->{result_class};
3382 # The reason we do this now instead of passing the alias to the
3383 # search_rs below is that if you wrap/overload resultset on the
3384 # source you need to know what alias it's -going- to have for things
3385 # to work sanely (e.g. RestrictWithObject wants to be able to add
3386 # extra query restrictions, and these may need to be $alias.)
3387 # -- mst ~ 2007 (01d59a6a6)
3389 # FIXME - this seems to be no longer neccessary (perhaps due to the
3390 # advances in relcond resolution. Testing DBIC::S::RWO and its only
3391 # dependent (as of Jun 2015 ) does not yield any difference with or
3392 # without this line. Nevertheless keep it as is for now, to minimize
3393 # churn, there is enough potential for breakage in 0.0829xx as it is
3394 # -- ribasushi Jun 2015
3396 my $rel_source = $rsrc->related_source($rel);
3397 local $rel_source->resultset_attributes->{alias} = $attrs->{alias};
3399 $rel_source->resultset->search_rs( undef, $attrs );
3402 if (my $cache = $self->get_cache) {
3403 my @related_cache = map
3404 { $_->related_resultset($rel)->get_cache || () }
3408 $new->set_cache([ map @$_, @related_cache ]) if @related_cache == @$cache;
3415 =head2 current_source_alias
3419 =item Arguments: none
3421 =item Return Value: $source_alias
3425 Returns the current table alias for the result source this resultset is built
3426 on, that will be used in the SQL query. Usually it is C<me>.
3428 Currently the source alias that refers to the result set returned by a
3429 L</search>/L</find> family method depends on how you got to the resultset: it's
3430 C<me> by default, but eg. L</search_related> aliases it to the related result
3431 source name (and keeps C<me> referring to the original result set). The long
3432 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3433 (and make this method unnecessary).
3435 Thus it's currently necessary to use this method in predefined queries (see
3436 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3437 source alias of the current result set:
3439 # in a result set class
3441 my ($self, $user) = @_;
3443 my $me = $self->current_source_alias;
3445 return $self->search({
3446 "$me.modified" => $user->id,
3450 The alias of L<newly created resultsets|/search> can be altered by the
3451 L<alias attribute|/alias>.
3455 sub current_source_alias {
3456 return (shift->{attrs} || {})->{alias} || 'me';
3459 =head2 as_subselect_rs
3463 =item Arguments: none
3465 =item Return Value: L<$resultset|/search>
3469 Act as a barrier to SQL symbols. The resultset provided will be made into a
3470 "virtual view" by including it as a subquery within the from clause. From this
3471 point on, any joined tables are inaccessible to ->search on the resultset (as if
3472 it were simply where-filtered without joins). For example:
3474 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3476 # 'x' now pollutes the query namespace
3478 # So the following works as expected
3479 my $ok_rs = $rs->search({'x.other' => 1});
3481 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3482 # def) we look for one row with contradictory terms and join in another table
3483 # (aliased 'x_2') which we never use
3484 my $broken_rs = $rs->search({'x.name' => 'def'});
3486 my $rs2 = $rs->as_subselect_rs;
3488 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3489 my $not_joined_rs = $rs2->search({'x.other' => 1});
3491 # works as expected: finds a 'table' row related to two x rows (abc and def)
3492 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3494 Another example of when one might use this would be to select a subset of
3495 columns in a group by clause:
3497 my $rs = $schema->resultset('Bar')->search(undef, {
3498 group_by => [qw{ id foo_id baz_id }],
3499 })->as_subselect_rs->search(undef, {
3500 columns => [qw{ id foo_id }]
3503 In the above example normally columns would have to be equal to the group by,
3504 but because we isolated the group by into a subselect the above works.
3508 sub as_subselect_rs {
3510 # FIXME - remove at some point in the future (2018-ish)
3514 'Starting with DBIC@0.082900 as_subselect_rs() always returns a ResultSet '
3515 . 'instance regardless of calling context. Please force scalar() context to '
3516 . 'silence this warning'
3521 my $alias = $self->current_source_alias;
3523 my $fresh_rs = (ref $self)->new (
3524 $self->result_source
3527 # these pieces will be locked in the subquery
3528 delete $fresh_rs->{cond};
3529 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3531 $fresh_rs->search_rs( {}, {
3533 $alias => $self->as_query,
3535 -rsrc => $self->result_source,
3541 # This code is called by search_related, and makes sure there
3542 # is clear separation between the joins before, during, and
3543 # after the relationship. This information is needed later
3544 # in order to properly resolve prefetch aliases (any alias
3545 # with a relation_chain_depth less than the depth of the
3546 # current prefetch is not considered)
3548 # The increments happen twice per join. An even number means a
3549 # relationship specified via a search_related, whereas an odd
3550 # number indicates a join/prefetch added via attributes
3552 # Also this code will wrap the current resultset (the one we
3553 # chain to) in a subselect IFF it contains limiting attributes
3554 sub _chain_relationship {
3555 my ($self, $rel) = @_;
3556 my $source = $self->result_source;
3557 my $attrs = { %{$self->{attrs}||{}} };
3559 # we need to take the prefetch the attrs into account before we
3560 # ->_resolve_join as otherwise they get lost - captainL
3561 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3563 delete @{$attrs}{qw/join prefetch collapse group_by distinct _grouped_by_distinct select as columns +select +as +columns/};
3565 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3568 my @force_subq_attrs = qw/offset rows group_by having/;
3571 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3573 $self->_has_resolved_attr (@force_subq_attrs)
3575 # Nuke the prefetch (if any) before the new $rs attrs
3576 # are resolved (prefetch is useless - we are wrapping
3577 # a subquery anyway).
3578 my $rs_copy = $self->search;
3579 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3580 $rs_copy->{attrs}{join},
3581 delete $rs_copy->{attrs}{prefetch},
3586 -alias => $attrs->{alias},
3587 $attrs->{alias} => $rs_copy->as_query,
3589 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3590 $seen->{-relation_chain_depth} = 0;
3592 elsif ($attrs->{from}) { #shallow copy suffices
3593 $from = [ @{$attrs->{from}} ];
3598 -alias => $attrs->{alias},
3599 $attrs->{alias} => $source->from,
3603 my $jpath = ($seen->{-relation_chain_depth})
3604 ? $from->[-1][0]{-join_path}
3607 my @requested_joins = $source->_resolve_join(
3614 push @$from, @requested_joins;
3616 $seen->{-relation_chain_depth}++;
3618 # if $self already had a join/prefetch specified on it, the requested
3619 # $rel might very well be already included. What we do in this case
3620 # is effectively a no-op (except that we bump up the chain_depth on
3621 # the join in question so we could tell it *is* the search_related)
3624 # we consider the last one thus reverse
3625 for my $j (reverse @requested_joins) {
3626 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3627 if ($rel eq $last_j) {
3628 $j->[0]{-relation_chain_depth}++;
3634 unless ($already_joined) {
3635 push @$from, $source->_resolve_join(
3643 $seen->{-relation_chain_depth}++;
3645 return {%$attrs, from => $from, seen_join => $seen};
3648 sub _resolved_attrs {
3650 return $self->{_attrs} if $self->{_attrs};
3652 my $attrs = { %{ $self->{attrs} || {} } };
3653 my $source = $attrs->{result_source} = $self->result_source;
3654 my $alias = $attrs->{alias};
3656 $self->throw_exception("Specifying distinct => 1 in conjunction with collapse => 1 is unsupported")
3657 if $attrs->{collapse} and $attrs->{distinct};
3660 # Sanity check the paging attributes
3661 # SQLMaker does it too, but in case of a software_limit we'll never get there
3662 if (defined $attrs->{offset}) {
3663 $self->throw_exception('A supplied offset attribute must be a non-negative integer')
3664 if ( $attrs->{offset} =~ /[^0-9]/ or $attrs->{offset} < 0 );
3666 if (defined $attrs->{rows}) {
3667 $self->throw_exception("The rows attribute must be a positive integer if present")
3668 if ( $attrs->{rows} =~ /[^0-9]/ or $attrs->{rows} <= 0 );
3671 # normalize where condition
3672 $attrs->{where} = normalize_sqla_condition( $attrs->{where} )
3675 # default selection list
3676 $attrs->{columns} = [ $source->columns ]
3677 unless grep { exists $attrs->{$_} } qw/columns cols select as/;
3679 # merge selectors together
3680 for (qw/columns select as/) {
3681 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3682 if $attrs->{$_} or $attrs->{"+$_"};
3685 # disassemble columns
3687 if (my $cols = delete $attrs->{columns}) {
3688 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3689 if (ref $c eq 'HASH') {
3690 for my $as (sort keys %$c) {
3691 push @sel, $c->{$as};
3702 # when trying to weed off duplicates later do not go past this point -
3703 # everything added from here on is unbalanced "anyone's guess" stuff
3704 my $dedup_stop_idx = $#as;
3706 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3708 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3709 if $attrs->{select};
3711 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3712 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3714 # disqualify all $alias.col as-bits (inflate-map mandated)
3715 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3717 # de-duplicate the result (remove *identical* select/as pairs)
3718 # and also die on duplicate {as} pointing to different {select}s
3719 # not using a c-style for as the condition is prone to shrinkage
3722 while ($i <= $dedup_stop_idx) {
3723 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3728 elsif ($seen->{$as[$i]}++) {
3729 $self->throw_exception(
3730 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3738 $attrs->{select} = \@sel;
3739 $attrs->{as} = \@as;
3741 $attrs->{from} ||= [{
3743 -alias => $self->{attrs}{alias},
3744 $self->{attrs}{alias} => $source->from,
3747 if ( $attrs->{join} || $attrs->{prefetch} ) {
3749 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3750 if ref $attrs->{from} ne 'ARRAY';
3752 my $join = (delete $attrs->{join}) || {};
3754 if ( defined $attrs->{prefetch} ) {
3755 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3758 $attrs->{from} = # have to copy here to avoid corrupting the original
3760 @{ $attrs->{from} },
3761 $source->_resolve_join(
3764 { %{ $attrs->{seen_join} || {} } },
3765 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3766 ? $attrs->{from}[-1][0]{-join_path}
3774 for my $attr (qw(order_by group_by)) {
3776 if ( defined $attrs->{$attr} ) {
3778 ref( $attrs->{$attr} ) eq 'ARRAY'
3779 ? [ @{ $attrs->{$attr} } ]
3780 : [ $attrs->{$attr} || () ]
3783 delete $attrs->{$attr} unless @{$attrs->{$attr}};
3788 # set collapse default based on presence of prefetch
3791 defined $attrs->{prefetch}
3793 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3795 $self->throw_exception("Specifying prefetch in conjunction with an explicit collapse => 0 is unsupported")
3796 if defined $attrs->{collapse} and ! $attrs->{collapse};
3798 $attrs->{collapse} = 1;
3802 # run through the resulting joinstructure (starting from our current slot)
3803 # and unset collapse if proven unnecessary
3805 # also while we are at it find out if the current root source has
3806 # been premultiplied by previous related_source chaining
3808 # this allows to predict whether a root object with all other relation
3809 # data set to NULL is in fact unique
3810 if ($attrs->{collapse}) {
3812 if (ref $attrs->{from} eq 'ARRAY') {
3814 if (@{$attrs->{from}} == 1) {
3815 # no joins - no collapse
3816 $attrs->{collapse} = 0;
3819 # find where our table-spec starts
3820 my @fromlist = @{$attrs->{from}};
3822 my $t = shift @fromlist;
3825 # me vs join from-spec distinction - a ref means non-root
3826 if (ref $t eq 'ARRAY') {
3828 $is_multi ||= ! $t->{-is_single};
3830 last if ($t->{-alias} && $t->{-alias} eq $alias);
3831 $attrs->{_main_source_premultiplied} ||= $is_multi;
3834 # no non-singles remaining, nor any premultiplication - nothing to collapse
3836 ! $attrs->{_main_source_premultiplied}
3838 ! grep { ! $_->[0]{-is_single} } @fromlist
3840 $attrs->{collapse} = 0;
3846 # if we can not analyze the from - err on the side of safety
3847 $attrs->{_main_source_premultiplied} = 1;
3852 # generate the distinct induced group_by before injecting the prefetched select/as parts
3853 if (delete $attrs->{distinct}) {
3854 if ($attrs->{group_by}) {
3855 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3858 $attrs->{_grouped_by_distinct} = 1;
3859 # distinct affects only the main selection part, not what prefetch may add below
3860 ($attrs->{group_by}, my $new_order) = $source->schema->storage->_group_over_selection($attrs);
3862 # FIXME possibly ignore a rewritten order_by (may turn out to be an issue)
3863 # The thinking is: if we are collapsing the subquerying prefetch engine will
3864 # rip stuff apart for us anyway, and we do not want to have a potentially
3865 # function-converted external order_by
3866 # ( there is an explicit if ( collapse && _grouped_by_distinct ) check in DBIHacks )
3867 $attrs->{order_by} = $new_order unless $attrs->{collapse};
3872 # generate selections based on the prefetch helper
3875 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3876 if $attrs->{_dark_selector};
3878 # this is a separate structure (we don't look in {from} directly)
3879 # as the resolver needs to shift things off the lists to work
3880 # properly (identical-prefetches on different branches)
3881 my $joined_node_aliases_map = {};
3882 if (ref $attrs->{from} eq 'ARRAY') {
3884 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3886 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3887 next unless $j->[0]{-alias};
3888 next unless $j->[0]{-join_path};
3889 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3891 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3893 my $p = $joined_node_aliases_map;
3894 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3895 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3899 ( push @{$attrs->{select}}, $_->[0] ) and ( push @{$attrs->{as}}, $_->[1] )
3900 for $source->_resolve_selection_from_prefetch( $prefetch, $joined_node_aliases_map );
3904 $attrs->{_simple_passthrough_construction} = !(
3907 grep { $_ =~ /\./ } @{$attrs->{as}}
3911 # if both page and offset are specified, produce a combined offset
3912 # even though it doesn't make much sense, this is what pre 081xx has
3914 if (my $page = delete $attrs->{page}) {
3916 ($attrs->{rows} * ($page - 1))
3918 ($attrs->{offset} || 0)
3922 return $self->{_attrs} = $attrs;
3926 my ($self, $attr) = @_;
3928 if (ref $attr eq 'HASH') {
3929 return $self->_rollout_hash($attr);
3930 } elsif (ref $attr eq 'ARRAY') {
3931 return $self->_rollout_array($attr);
3937 sub _rollout_array {
3938 my ($self, $attr) = @_;
3941 foreach my $element (@{$attr}) {
3942 if (ref $element eq 'HASH') {
3943 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3944 } elsif (ref $element eq 'ARRAY') {
3945 # XXX - should probably recurse here
3946 push( @rolled_array, @{$self->_rollout_array($element)} );
3948 push( @rolled_array, $element );
3951 return \@rolled_array;
3955 my ($self, $attr) = @_;
3958 foreach my $key (keys %{$attr}) {
3959 push( @rolled_array, { $key => $attr->{$key} } );
3961 return \@rolled_array;
3964 sub _calculate_score {
3965 my ($self, $a, $b) = @_;
3967 if (defined $a xor defined $b) {
3970 elsif (not defined $a) {
3974 if (ref $b eq 'HASH') {
3975 my ($b_key) = keys %{$b};
3976 $b_key = '' if ! defined $b_key;
3977 if (ref $a eq 'HASH') {
3978 my ($a_key) = keys %{$a};
3979 $a_key = '' if ! defined $a_key;
3980 if ($a_key eq $b_key) {
3981 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3986 return ($a eq $b_key) ? 1 : 0;
3989 if (ref $a eq 'HASH') {
3990 my ($a_key) = keys %{$a};
3991 return ($b eq $a_key) ? 1 : 0;
3993 return ($b eq $a) ? 1 : 0;
3998 sub _merge_joinpref_attr {
3999 my ($self, $orig, $import) = @_;
4001 return $import unless defined($orig);
4002 return $orig unless defined($import);
4004 $orig = $self->_rollout_attr($orig);
4005 $import = $self->_rollout_attr($import);
4008 foreach my $import_element ( @{$import} ) {
4009 # find best candidate from $orig to merge $b_element into
4010 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
4011 foreach my $orig_element ( @{$orig} ) {
4012 my $score = $self->_calculate_score( $orig_element, $import_element );
4013 if ($score > $best_candidate->{score}) {
4014 $best_candidate->{position} = $position;
4015 $best_candidate->{score} = $score;
4019 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
4020 $import_key = '' if not defined $import_key;
4022 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
4023 push( @{$orig}, $import_element );
4025 my $orig_best = $orig->[$best_candidate->{position}];
4026 # merge orig_best and b_element together and replace original with merged
4027 if (ref $orig_best ne 'HASH') {
4028 $orig->[$best_candidate->{position}] = $import_element;
4029 } elsif (ref $import_element eq 'HASH') {
4030 my ($key) = keys %{$orig_best};
4031 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
4034 $seen_keys->{$import_key} = 1; # don't merge the same key twice
4037 return @$orig ? $orig : ();
4045 require Hash::Merge;
4046 my $hm = Hash::Merge->new;
4048 $hm->specify_behavior({
4051 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
4053 if ($defl xor $defr) {
4054 return [ $defl ? $_[0] : $_[1] ];
4059 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
4063 return [$_[0], $_[1]];
4067 return $_[1] if !defined $_[0];
4068 return $_[1] if __HM_DEDUP and grep { $_ eq $_[0] } @{$_[1]};
4069 return [$_[0], @{$_[1]}]
4072 return [] if !defined $_[0] and !keys %{$_[1]};
4073 return [ $_[1] ] if !defined $_[0];
4074 return [ $_[0] ] if !keys %{$_[1]};
4075 return [$_[0], $_[1]]
4080 return $_[0] if !defined $_[1];
4081 return $_[0] if __HM_DEDUP and grep { $_ eq $_[1] } @{$_[0]};
4082 return [@{$_[0]}, $_[1]]
4085 my @ret = @{$_[0]} or return $_[1];
4086 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
4087 my %idx = map { $_ => 1 } @ret;
4088 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
4092 return [ $_[1] ] if ! @{$_[0]};
4093 return $_[0] if !keys %{$_[1]};
4094 return $_[0] if __HM_DEDUP and grep { $_ eq $_[1] } @{$_[0]};
4095 return [ @{$_[0]}, $_[1] ];
4100 return [] if !keys %{$_[0]} and !defined $_[1];
4101 return [ $_[0] ] if !defined $_[1];
4102 return [ $_[1] ] if !keys %{$_[0]};
4103 return [$_[0], $_[1]]
4106 return [] if !keys %{$_[0]} and !@{$_[1]};
4107 return [ $_[0] ] if !@{$_[1]};
4108 return $_[1] if !keys %{$_[0]};
4109 return $_[1] if __HM_DEDUP and grep { $_ eq $_[0] } @{$_[1]};
4110 return [ $_[0], @{$_[1]} ];
4113 return [] if !keys %{$_[0]} and !keys %{$_[1]};
4114 return [ $_[0] ] if !keys %{$_[1]};
4115 return [ $_[1] ] if !keys %{$_[0]};
4116 return [ $_[0] ] if $_[0] eq $_[1];
4117 return [ $_[0], $_[1] ];
4120 } => 'DBIC_RS_ATTR_MERGER');
4124 return $hm->merge ($_[1], $_[2]);
4128 sub STORABLE_freeze {
4129 my ($self, $cloning) = @_;
4130 my $to_serialize = { %$self };
4132 # A cursor in progress can't be serialized (and would make little sense anyway)
4133 # the parser can be regenerated (and can't be serialized)
4134 delete @{$to_serialize}{qw/cursor _row_parser _result_inflator/};
4136 # nor is it sensical to store a not-yet-fired-count pager
4137 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
4138 delete $to_serialize->{pager};
4141 Storable::nfreeze($to_serialize);
4144 # need this hook for symmetry
4146 my ($self, $cloning, $serialized) = @_;
4148 %$self = %{ Storable::thaw($serialized) };
4154 =head2 throw_exception
4156 See L<DBIx::Class::Schema/throw_exception> for details.
4160 sub throw_exception {
4163 if (ref $self and my $rsrc = $self->result_source) {
4164 $rsrc->throw_exception(@_)
4167 DBIx::Class::Exception->throw(@_);
4175 # XXX: FIXME: Attributes docs need clearing up
4179 Attributes are used to refine a ResultSet in various ways when
4180 searching for data. They can be passed to any method which takes an
4181 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
4184 Default attributes can be set on the result class using
4185 L<DBIx::Class::ResultSource/resultset_attributes>. (Please read
4186 the CAVEATS on that feature before using it!)
4188 These are in no particular order:
4194 =item Value: ( $order_by | \@order_by | \%order_by )
4198 Which column(s) to order the results by.
4200 [The full list of suitable values is documented in
4201 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
4204 If a single column name, or an arrayref of names is supplied, the
4205 argument is passed through directly to SQL. The hashref syntax allows
4206 for connection-agnostic specification of ordering direction:
4208 For descending order:
4210 order_by => { -desc => [qw/col1 col2 col3/] }
4212 For explicit ascending order:
4214 order_by => { -asc => 'col' }
4216 The old scalarref syntax (i.e. order_by => \'year DESC') is still
4217 supported, although you are strongly encouraged to use the hashref
4218 syntax as outlined above.
4224 =item Value: \@columns | \%columns | $column
4228 Shortcut to request a particular set of columns to be retrieved. Each
4229 column spec may be a string (a table column name), or a hash (in which
4230 case the key is the C<as> value, and the value is used as the C<select>
4231 expression). Adds the L</current_source_alias> onto the start of any column without a C<.> in
4232 it and sets C<select> from that, then auto-populates C<as> from
4233 C<select> as normal. (You may also use the C<cols> attribute, as in
4234 earlier versions of DBIC, but this is deprecated)
4236 Essentially C<columns> does the same as L</select> and L</as>.
4238 columns => [ 'some_column', { dbic_slot => 'another_column' } ]
4242 select => [qw(some_column another_column)],
4243 as => [qw(some_column dbic_slot)]
4245 If you want to individually retrieve related columns (in essence perform
4246 manual L</prefetch>) you have to make sure to specify the correct inflation slot
4247 chain such that it matches existing relationships:
4249 my $rs = $schema->resultset('Artist')->search({}, {
4250 # required to tell DBIC to collapse has_many relationships
4252 join => { cds => 'tracks' },
4254 'cds.cdid' => 'cds.cdid',
4255 'cds.tracks.title' => 'tracks.title',
4259 Like elsewhere, literal SQL or literal values can be included by using a
4260 scalar reference or a literal bind value, and these values will be available
4261 in the result with C<get_column> (see also
4262 L<SQL::Abstract/Literal SQL and value type operators>):
4264 # equivalent SQL: SELECT 1, 'a string', IF(my_column,?,?) ...
4265 # bind values: $true_value, $false_value
4269 bar => \q{'a string'},
4270 baz => \[ 'IF(my_column,?,?)', $true_value, $false_value ],
4276 B<NOTE:> You B<MUST> explicitly quote C<'+columns'> when using this attribute.
4277 Not doing so causes Perl to incorrectly interpret C<+columns> as a bareword
4278 with a unary plus operator before it, which is the same as simply C<columns>.
4282 =item Value: \@extra_columns
4286 Indicates additional columns to be selected from storage. Works the same as
4287 L</columns> but adds columns to the current selection. (You may also use the
4288 C<include_columns> attribute, as in earlier versions of DBIC, but this is
4291 $schema->resultset('CD')->search(undef, {
4292 '+columns' => ['artist.name'],
4296 would return all CDs and include a 'name' column to the information
4297 passed to object inflation. Note that the 'artist' is the name of the
4298 column (or relationship) accessor, and 'name' is the name of the column
4299 accessor in the related table.
4305 =item Value: \@select_columns
4309 Indicates which columns should be selected from the storage. You can use
4310 column names, or in the case of RDBMS back ends, function or stored procedure
4313 $rs = $schema->resultset('Employee')->search(undef, {
4316 { count => 'employeeid' },
4317 { max => { length => 'name' }, -as => 'longest_name' }
4322 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
4324 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
4325 use L</select>, to instruct DBIx::Class how to store the result of the column.
4327 Also note that the L</as> attribute has B<nothing to do> with the SQL-side
4328 C<AS> identifier aliasing. You B<can> alias a function (so you can use it e.g.
4329 in an C<ORDER BY> clause), however this is done via the C<-as> B<select
4330 function attribute> supplied as shown in the example above.
4334 B<NOTE:> You B<MUST> explicitly quote C<'+select'> when using this attribute.
4335 Not doing so causes Perl to incorrectly interpret C<+select> as a bareword
4336 with a unary plus operator before it, which is the same as simply C<select>.
4340 =item Value: \@extra_select_columns
4344 Indicates additional columns to be selected from storage. Works the same as
4345 L</select> but adds columns to the current selection, instead of specifying
4346 a new explicit list.
4352 =item Value: \@inflation_names
4356 Indicates DBIC-side names for object inflation. That is L</as> indicates the
4357 slot name in which the column value will be stored within the
4358 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
4359 identifier by the C<get_column> method (or via the object accessor B<if one
4360 with the same name already exists>) as shown below.
4362 The L</as> attribute has B<nothing to do> with the SQL-side identifier
4363 aliasing C<AS>. See L</select> for details.
4365 $rs = $schema->resultset('Employee')->search(undef, {
4368 { count => 'employeeid' },
4369 { max => { length => 'name' }, -as => 'longest_name' }
4378 If the object against which the search is performed already has an accessor
4379 matching a column name specified in C<as>, the value can be retrieved using
4380 the accessor as normal:
4382 my $name = $employee->name();
4384 If on the other hand an accessor does not exist in the object, you need to
4385 use C<get_column> instead:
4387 my $employee_count = $employee->get_column('employee_count');
4389 You can create your own accessors if required - see
4390 L<DBIx::Class::Manual::Cookbook> for details.
4394 B<NOTE:> You B<MUST> explicitly quote C<'+as'> when using this attribute.
4395 Not doing so causes Perl to incorrectly interpret C<+as> as a bareword
4396 with a unary plus operator before it, which is the same as simply C<as>.
4400 =item Value: \@extra_inflation_names
4404 Indicates additional inflation names for selectors added via L</+select>. See L</as>.
4410 =item Value: ($rel_name | \@rel_names | \%rel_names)
4414 Contains a list of relationships that should be joined for this query. For
4417 # Get CDs by Nine Inch Nails
4418 my $rs = $schema->resultset('CD')->search(
4419 { 'artist.name' => 'Nine Inch Nails' },
4420 { join => 'artist' }
4423 Can also contain a hash reference to refer to the other relation's relations.
4426 package MyApp::Schema::Track;
4427 use base qw/DBIx::Class/;
4428 __PACKAGE__->table('track');
4429 __PACKAGE__->add_columns(qw/trackid cd position title/);
4430 __PACKAGE__->set_primary_key('trackid');
4431 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
4434 # In your application
4435 my $rs = $schema->resultset('Artist')->search(
4436 { 'track.title' => 'Teardrop' },
4438 join => { cd => 'track' },
4439 order_by => 'artist.name',
4443 You need to use the relationship (not the table) name in conditions,
4444 because they are aliased as such. The current table is aliased as "me", so
4445 you need to use me.column_name in order to avoid ambiguity. For example:
4447 # Get CDs from 1984 with a 'Foo' track
4448 my $rs = $schema->resultset('CD')->search(
4451 'tracks.name' => 'Foo'
4453 { join => 'tracks' }
4456 If the same join is supplied twice, it will be aliased to <rel>_2 (and
4457 similarly for a third time). For e.g.
4459 my $rs = $schema->resultset('Artist')->search({
4460 'cds.title' => 'Down to Earth',
4461 'cds_2.title' => 'Popular',
4463 join => [ qw/cds cds/ ],
4466 will return a set of all artists that have both a cd with title 'Down
4467 to Earth' and a cd with title 'Popular'.
4469 If you want to fetch related objects from other tables as well, see L</prefetch>
4472 NOTE: An internal join-chain pruner will discard certain joins while
4473 constructing the actual SQL query, as long as the joins in question do not
4474 affect the retrieved result. This for example includes 1:1 left joins
4475 that are not part of the restriction specification (WHERE/HAVING) nor are
4476 a part of the query selection.
4478 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4484 =item Value: (0 | 1)
4488 When set to a true value, indicates that any rows fetched from joined has_many
4489 relationships are to be aggregated into the corresponding "parent" object. For
4490 example, the resultset:
4492 my $rs = $schema->resultset('CD')->search({}, {
4493 '+columns' => [ qw/ tracks.title tracks.position / ],
4498 While executing the following query:
4500 SELECT me.*, tracks.title, tracks.position
4502 LEFT JOIN track tracks
4503 ON tracks.cdid = me.cdid
4505 Will return only as many objects as there are rows in the CD source, even
4506 though the result of the query may span many rows. Each of these CD objects
4507 will in turn have multiple "Track" objects hidden behind the has_many
4508 generated accessor C<tracks>. Without C<< collapse => 1 >>, the return values
4509 of this resultset would be as many CD objects as there are tracks (a "Cartesian
4510 product"), with each CD object containing exactly one of all fetched Track data.
4512 When a collapse is requested on a non-ordered resultset, an order by some
4513 unique part of the main source (the left-most table) is inserted automatically.
4514 This is done so that the resultset is allowed to be "lazy" - calling
4515 L<< $rs->next|/next >> will fetch only as many rows as it needs to build the next
4516 object with all of its related data.
4518 If an L</order_by> is already declared, and orders the resultset in a way that
4519 makes collapsing as described above impossible (e.g. C<< ORDER BY
4520 has_many_rel.column >> or C<ORDER BY RANDOM()>), DBIC will automatically
4521 switch to "eager" mode and slurp the entire resultset before constructing the
4522 first object returned by L</next>.
4524 Setting this attribute on a resultset that does not join any has_many
4525 relations is a no-op.
4527 For a more in-depth discussion, see L</PREFETCHING>.
4533 =item Value: ($rel_name | \@rel_names | \%rel_names)
4537 This attribute is a shorthand for specifying a L</join> spec, adding all
4538 columns from the joined related sources as L</+columns> and setting
4539 L</collapse> to a true value. It can be thought of as a rough B<superset>
4540 of the L</join> attribute.
4542 For example, the following two queries are equivalent:
4544 my $rs = $schema->resultset('Artist')->search({}, {
4545 prefetch => { cds => ['genre', 'tracks' ] },
4550 my $rs = $schema->resultset('Artist')->search({}, {
4551 join => { cds => ['genre', 'tracks' ] },
4555 { +{ "cds.$_" => "cds.$_" } }
4556 $schema->source('Artist')->related_source('cds')->columns
4559 { +{ "cds.genre.$_" => "genre.$_" } }
4560 $schema->source('Artist')->related_source('cds')->related_source('genre')->columns
4563 { +{ "cds.tracks.$_" => "tracks.$_" } }
4564 $schema->source('Artist')->related_source('cds')->related_source('tracks')->columns
4569 Both producing the following SQL:
4571 SELECT me.artistid, me.name, me.rank, me.charfield,
4572 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track,
4573 genre.genreid, genre.name,
4574 tracks.trackid, tracks.cd, tracks.position, tracks.title, tracks.last_updated_on, tracks.last_updated_at
4577 ON cds.artist = me.artistid
4578 LEFT JOIN genre genre
4579 ON genre.genreid = cds.genreid
4580 LEFT JOIN track tracks
4581 ON tracks.cd = cds.cdid
4582 ORDER BY me.artistid
4584 While L</prefetch> implies a L</join>, it is ok to mix the two together, as
4585 the arguments are properly merged and generally do the right thing. For
4586 example, you may want to do the following:
4588 my $artists_and_cds_without_genre = $schema->resultset('Artist')->search(
4589 { 'genre.genreid' => undef },
4591 join => { cds => 'genre' },
4596 Which generates the following SQL:
4598 SELECT me.artistid, me.name, me.rank, me.charfield,
4599 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track
4602 ON cds.artist = me.artistid
4603 LEFT JOIN genre genre
4604 ON genre.genreid = cds.genreid
4605 WHERE genre.genreid IS NULL
4606 ORDER BY me.artistid
4608 For a more in-depth discussion, see L</PREFETCHING>.
4614 =item Value: $source_alias
4618 Sets the source alias for the query. Normally, this defaults to C<me>, but
4619 nested search queries (sub-SELECTs) might need specific aliases set to
4620 reference inner queries. For example:
4623 ->related_resultset('CDs')
4624 ->related_resultset('Tracks')
4626 'track.id' => { -ident => 'none_search.id' },
4630 my $ids = $self->search({
4633 alias => 'none_search',
4634 group_by => 'none_search.id',
4635 })->get_column('id')->as_query;
4637 $self->search({ id => { -in => $ids } })
4639 This attribute is directly tied to L</current_source_alias>.
4649 Makes the resultset paged and specifies the page to retrieve. Effectively
4650 identical to creating a non-pages resultset and then calling ->page($page)
4653 If L</rows> attribute is not specified it defaults to 10 rows per page.
4655 When you have a paged resultset, L</count> will only return the number
4656 of rows in the page. To get the total, use the L</pager> and call
4657 C<total_entries> on it.
4667 Specifies the maximum number of rows for direct retrieval or the number of
4668 rows per page if the page attribute or method is used.
4674 =item Value: $offset
4678 Specifies the (zero-based) row number for the first row to be returned, or the
4679 of the first row of the first page if paging is used.
4681 =head2 software_limit
4685 =item Value: (0 | 1)
4689 When combined with L</rows> and/or L</offset> the generated SQL will not
4690 include any limit dialect stanzas. Instead the entire result will be selected
4691 as if no limits were specified, and DBIC will perform the limit locally, by
4692 artificially advancing and finishing the resulting L</cursor>.
4694 This is the recommended way of performing resultset limiting when no sane RDBMS
4695 implementation is available (e.g.
4696 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4697 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4703 =item Value: \@columns
4707 A arrayref of columns to group by. Can include columns of joined tables.
4709 group_by => [qw/ column1 column2 ... /]
4715 =item Value: $condition
4719 The HAVING operator specifies a B<secondary> condition applied to the set
4720 after the grouping calculations have been done. In other words it is a
4721 constraint just like L</where> (and accepting the same
4722 L<SQL::Abstract syntax|SQL::Abstract/WHERE CLAUSES>) applied to the data
4723 as it exists after GROUP BY has taken place. Specifying L</having> without
4724 L</group_by> is a logical mistake, and a fatal error on most RDBMS engines.
4728 having => { 'count_employee' => { '>=', 100 } }
4730 or with an in-place function in which case literal SQL is required:
4732 having => \[ 'count(employee) >= ?', 100 ]
4738 =item Value: (0 | 1)
4742 Set to 1 to automatically generate a L</group_by> clause based on the selection
4743 (including intelligent handling of L</order_by> contents). Note that the group
4744 criteria calculation takes place over the B<final> selection. This includes
4745 any L</+columns>, L</+select> or L</order_by> additions in subsequent
4746 L</search> calls, and standalone columns selected via
4747 L<DBIx::Class::ResultSetColumn> (L</get_column>). A notable exception are the
4748 extra selections specified via L</prefetch> - such selections are explicitly
4749 excluded from group criteria calculations.
4751 If the final ResultSet also explicitly defines a L</group_by> attribute, this
4752 setting is ignored and an appropriate warning is issued.
4756 Adds extra conditions to the resultset, combined with the preexisting C<WHERE>
4757 conditions, same as the B<first> argument to the L<search operator|/search>
4759 # only return rows WHERE deleted IS NULL for all searches
4760 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4762 Note that the above example is
4763 L<strongly discouraged|DBIx::Class::ResultSource/resultset_attributes>.
4767 Set to 1 to cache search results. This prevents extra SQL queries if you
4768 revisit rows in your ResultSet:
4770 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4772 while( my $artist = $resultset->next ) {
4776 $resultset->first; # without cache, this would issue a query
4778 By default, searches are not cached.
4780 For more examples of using these attributes, see
4781 L<DBIx::Class::Manual::Cookbook>.
4787 =item Value: ( 'update' | 'shared' | \$scalar )
4791 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4792 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4797 DBIx::Class supports arbitrary related data prefetching from multiple related
4798 sources. Any combination of relationship types and column sets are supported.
4799 If L<collapsing|/collapse> is requested, there is an additional requirement of
4800 selecting enough data to make every individual object uniquely identifiable.
4802 Here are some more involved examples, based on the following relationship map:
4805 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4806 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4807 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4809 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4811 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4815 my $rs = $schema->resultset('Tag')->search(
4824 The initial search results in SQL like the following:
4826 SELECT tag.*, cd.*, artist.* FROM tag
4827 JOIN cd ON tag.cd = cd.cdid
4828 JOIN artist ON cd.artist = artist.artistid
4830 L<DBIx::Class> has no need to go back to the database when we access the
4831 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4834 Simple prefetches will be joined automatically, so there is no need
4835 for a C<join> attribute in the above search.
4837 The L</prefetch> attribute can be used with any of the relationship types
4838 and multiple prefetches can be specified together. Below is a more complex
4839 example that prefetches a CD's artist, its liner notes (if present),
4840 the cover image, the tracks on that CD, and the guests on those
4843 my $rs = $schema->resultset('CD')->search(
4847 { artist => 'record_label'}, # belongs_to => belongs_to
4848 'liner_note', # might_have
4849 'cover_image', # has_one
4850 { tracks => 'guests' }, # has_many => has_many
4855 This will produce SQL like the following:
4857 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4861 ON artist.artistid = me.artistid
4862 JOIN record_label record_label
4863 ON record_label.labelid = artist.labelid
4864 LEFT JOIN track tracks
4865 ON tracks.cdid = me.cdid
4866 LEFT JOIN guest guests
4867 ON guests.trackid = track.trackid
4868 LEFT JOIN liner_notes liner_note
4869 ON liner_note.cdid = me.cdid
4870 JOIN cd_artwork cover_image
4871 ON cover_image.cdid = me.cdid
4874 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4875 C<tracks>, and C<guests> of the CD will all be available through the
4876 relationship accessors without the need for additional queries to the
4881 Prefetch does a lot of deep magic. As such, it may not behave exactly
4882 as you might expect.
4888 Prefetch uses the L</cache> to populate the prefetched relationships. This
4889 may or may not be what you want.
4893 If you specify a condition on a prefetched relationship, ONLY those
4894 rows that match the prefetched condition will be fetched into that relationship.
4895 This means that adding prefetch to a search() B<may alter> what is returned by
4896 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4898 my $artist_rs = $schema->resultset('Artist')->search({
4904 my $count = $artist_rs->first->cds->count;
4906 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4908 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4910 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4912 That cmp_ok() may or may not pass depending on the datasets involved. In other
4913 words the C<WHERE> condition would apply to the entire dataset, just like
4914 it would in regular SQL. If you want to add a condition only to the "right side"
4915 of a C<LEFT JOIN> - consider declaring and using a L<relationship with a custom
4916 condition|DBIx::Class::Relationship::Base/condition>
4920 =head1 DBIC BIND VALUES
4922 Because DBIC may need more information to bind values than just the column name
4923 and value itself, it uses a special format for both passing and receiving bind
4924 values. Each bind value should be composed of an arrayref of
4925 C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
4931 If present (in any form), this is what is being passed directly to bind_param.
4932 Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
4933 a single numerical type, while DBD::Pg takes a hashref if bind options.)
4935 If this is specified, all other bind options described below are ignored.
4939 If present, this is used to infer the actual bind attribute by passing to
4940 C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
4941 "data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
4943 Note that the data type is somewhat freeform (hence the sqlt_ prefix);
4944 currently drivers are expected to "Do the Right Thing" when given a common
4945 datatype name. (Not ideal, but that's what we got at this point.)
4949 Currently used to correctly allocate buffers for bind_param_inout().
4950 Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
4951 or to a sensible value based on the "data_type".
4955 Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
4956 explicitly specified they are never overridden). Also used by some weird DBDs,
4957 where the column name should be available at bind_param time (e.g. Oracle).
4961 For backwards compatibility and convenience, the following shortcuts are
4964 [ $name => $val ] === [ { dbic_colname => $name }, $val ]
4965 [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
4966 [ undef, $val ] === [ {}, $val ]
4967 $val === [ {}, $val ]
4969 =head1 FURTHER QUESTIONS?
4971 Check the list of L<additional DBIC resources|DBIx::Class/GETTING HELP/SUPPORT>.
4973 =head1 COPYRIGHT AND LICENSE
4975 This module is free software L<copyright|DBIx::Class/COPYRIGHT AND LICENSE>
4976 by the L<DBIx::Class (DBIC) authors|DBIx::Class/AUTHORS>. You can
4977 redistribute it and/or modify it under the same terms as the
4978 L<DBIx::Class library|DBIx::Class/COPYRIGHT AND LICENSE>.