1 package DBIx::Class::ResultSet;
6 use base 'DBIx::Class';
9 use DBIx::Class::ResultSetColumn;
10 use DBIx::Class::ResultClass::HashRefInflator;
11 use Scalar::Util qw( blessed reftype );
12 use DBIx::Class::_Util qw(
13 dbic_internal_try dump_value
14 fail_on_internal_wantarray fail_on_internal_call UNRESOLVABLE_CONDITION
19 # De-duplication in _merge_attr() is disabled, but left in for reference
20 # (the merger is used for other things that ought not to be de-duped)
21 *__HM_DEDUP = sub () { 0 };
31 # this is real - CDBICompat overrides it with insanity
32 # yes, prototype won't matter, but that's for now ;)
35 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class result_source/);
39 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
43 my $users_rs = $schema->resultset('User');
44 while( $user = $users_rs->next) {
45 print $user->username;
48 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
49 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
53 A ResultSet is an object which stores a set of conditions representing
54 a query. It is the backbone of DBIx::Class (i.e. the really
55 important/useful bit).
57 No SQL is executed on the database when a ResultSet is created, it
58 just stores all the conditions needed to create the query.
60 A basic ResultSet representing the data of an entire table is returned
61 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
62 L<Source|DBIx::Class::Manual::Glossary/ResultSource> name.
64 my $users_rs = $schema->resultset('User');
66 A new ResultSet is returned from calling L</search> on an existing
67 ResultSet. The new one will contain all the conditions of the
68 original, plus any new conditions added in the C<search> call.
70 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
71 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
74 The query that the ResultSet represents is B<only> executed against
75 the database when these methods are called:
76 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
78 If a resultset is used in a numeric context it returns the L</count>.
79 However, if it is used in a boolean context it is B<always> true. So if
80 you want to check if a resultset has any results, you must use C<if $rs
85 =head2 Chaining resultsets
87 Let's say you've got a query that needs to be run to return some data
88 to the user. But, you have an authorization system in place that
89 prevents certain users from seeing certain information. So, you want
90 to construct the basic query in one method, but add constraints to it in
95 my $request = $self->get_request; # Get a request object somehow.
96 my $schema = $self->result_source->schema;
98 my $cd_rs = $schema->resultset('CD')->search({
99 title => $request->param('title'),
100 year => $request->param('year'),
103 $cd_rs = $self->apply_security_policy( $cd_rs );
105 return $cd_rs->all();
108 sub apply_security_policy {
117 =head3 Resolving conditions and attributes
119 When a resultset is chained from another resultset (e.g.:
120 C<< my $new_rs = $old_rs->search(\%extra_cond, \%attrs) >>), conditions
121 and attributes with the same keys need resolving.
123 If any of L</columns>, L</select>, L</as> are present, they reset the
124 original selection, and start the selection "clean".
126 The L</join>, L</prefetch>, L</+columns>, L</+select>, L</+as> attributes
127 are merged into the existing ones from the original resultset.
129 The L</where> and L</having> attributes, and any search conditions, are
130 merged with an SQL C<AND> to the existing condition from the original
133 All other attributes are overridden by any new ones supplied in the
136 =head2 Multiple queries
138 Since a resultset just defines a query, you can do all sorts of
139 things with it with the same object.
141 # Don't hit the DB yet.
142 my $cd_rs = $schema->resultset('CD')->search({
143 title => 'something',
147 # Each of these hits the DB individually.
148 my $count = $cd_rs->count;
149 my $most_recent = $cd_rs->get_column('date_released')->max();
150 my @records = $cd_rs->all;
152 And it's not just limited to SELECT statements.
158 $cd_rs->create({ artist => 'Fred' });
160 Which is the same as:
162 $schema->resultset('CD')->create({
163 title => 'something',
168 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
170 =head2 Custom ResultSet classes
172 To add methods to your resultsets, you can subclass L<DBIx::Class::ResultSet>, similar to:
174 package MyApp::Schema::ResultSet::User;
179 use base 'DBIx::Class::ResultSet';
183 $self->search({ $self->current_source_alias . '.active' => 1 });
188 $self->search({ $self->current_source_alias . '.verified' => 0 });
191 sub created_n_days_ago {
192 my ($self, $days_ago) = @_;
194 $self->current_source_alias . '.create_date' => {
196 $self->result_source->schema->storage->datetime_parser->format_datetime(
197 DateTime->now( time_zone => 'UTC' )->subtract( days => $days_ago )
202 sub users_to_warn { shift->active->unverified->created_n_days_ago(7) }
206 See L<DBIx::Class::Schema/load_namespaces> on how DBIC can discover and
207 automatically attach L<Result|DBIx::Class::Manual::ResultClass>-specific
208 L<ResulSet|DBIx::Class::ResultSet> classes.
210 =head3 ResultSet subclassing with Moose and similar constructor-providers
212 Using L<Moose> or L<Moo> in your ResultSet classes is usually overkill, but
213 you may find it useful if your ResultSets contain a lot of business logic
214 (e.g. C<has xml_parser>, C<has json>, etc) or if you just prefer to organize
217 In order to write custom ResultSet classes with L<Moo> you need to use the
218 following template. The L<BUILDARGS|Moo/BUILDARGS> is necessary due to the
219 unusual signature of the L<constructor provided by DBIC
220 |DBIx::Class::ResultSet/new> C<< ->new($source, \%args) >>.
223 extends 'DBIx::Class::ResultSet';
224 sub BUILDARGS { $_[2] } # ::RS::new() expects my ($class, $rsrc, $args) = @_
230 If you want to build your custom ResultSet classes with L<Moose>, you need
231 a similar, though a little more elaborate template in order to interface the
232 inlining of the L<Moose>-provided
233 L<object constructor|Moose::Manual::Construction/WHERE'S THE CONSTRUCTOR?>,
236 package MyApp::Schema::ResultSet::User;
239 use MooseX::NonMoose;
240 extends 'DBIx::Class::ResultSet';
242 sub BUILDARGS { $_[2] } # ::RS::new() expects my ($class, $rsrc, $args) = @_
246 __PACKAGE__->meta->make_immutable;
250 The L<MooseX::NonMoose> is necessary so that the L<Moose> constructor does not
251 entirely overwrite the DBIC one (in contrast L<Moo> does this automatically).
252 Alternatively, you can skip L<MooseX::NonMoose> and get by with just L<Moose>
255 __PACKAGE__->meta->make_immutable(inline_constructor => 0);
263 =item Arguments: L<$source|DBIx::Class::ResultSource>, L<\%attrs?|/ATTRIBUTES>
265 =item Return Value: L<$resultset|/search>
269 The resultset constructor. Takes a source object (usually a
270 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
271 L</ATTRIBUTES> below). Does not perform any queries -- these are
272 executed as needed by the other methods.
274 Generally you never construct a resultset manually. Instead you get one
276 C<< $schema->L<resultset|DBIx::Class::Schema/resultset>('$source_name') >>
277 or C<< $another_resultset->L<search|/search>(...) >> (the later called in
280 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
286 If called on an object, proxies to L</new_result> instead, so
288 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
290 will return a CD object, not a ResultSet, and is equivalent to:
292 my $cd = $schema->resultset('CD')->new_result({ title => 'Spoon' });
294 Please also keep in mind that many internals call L</new_result> directly,
295 so overloading this method with the idea of intercepting new result object
296 creation B<will not work>. See also warning pertaining to L</create>.
306 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
307 return $class->new_result(@_);
310 my ($source, $attrs) = @_;
311 $source = $source->resolve
312 if $source->isa('DBIx::Class::ResultSourceHandle');
314 $attrs = { %{$attrs||{}} };
315 delete @{$attrs}{qw(_last_sqlmaker_alias_map _simple_passthrough_construction)};
317 if ($attrs->{page}) {
318 $attrs->{rows} ||= 10;
321 $attrs->{alias} ||= 'me';
324 result_source => $source,
325 cond => $attrs->{where},
330 # if there is a dark selector, this means we are already in a
331 # chain and the cleanup/sanification was taken care of by
333 $self->_normalize_selection($attrs)
334 unless $attrs->{_dark_selector};
337 $attrs->{result_class} || $source->result_class
347 =item Arguments: L<$cond|DBIx::Class::SQLMaker> | undef, L<\%attrs?|/ATTRIBUTES>
349 =item Return Value: $resultset (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
353 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
354 my $new_rs = $cd_rs->search({ year => 2005 });
356 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
357 # year = 2005 OR year = 2004
359 In list context, C<< ->all() >> is called implicitly on the resultset, thus
360 returning a list of L<result|DBIx::Class::Manual::ResultClass> objects instead.
361 To avoid that, use L</search_rs>.
363 If you need to pass in additional attributes but no additional condition,
364 call it as C<search(undef, \%attrs)>.
366 # "SELECT name, artistid FROM $artist_table"
367 my @all_artists = $schema->resultset('Artist')->search(undef, {
368 columns => [qw/name artistid/],
371 For a list of attributes that can be passed to C<search>, see
372 L</ATTRIBUTES>. For more examples of using this function, see
373 L<Searching|DBIx::Class::Manual::Cookbook/SEARCHING>. For a complete
374 documentation for the first argument, see L<SQL::Abstract/"WHERE CLAUSES">
375 and its extension L<DBIx::Class::SQLMaker>.
377 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
381 Note that L</search> does not process/deflate any of the values passed in the
382 L<SQL::Abstract>-compatible search condition structure. This is unlike other
383 condition-bound methods L</new_result>, L</create> and L</find>. The user must ensure
384 manually that any value passed to this method will stringify to something the
385 RDBMS knows how to deal with. A notable example is the handling of L<DateTime>
386 objects, for more info see:
387 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
393 my $rs = $self->search_rs( @_ );
396 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_WANTARRAY and my $sog = fail_on_internal_wantarray;
399 elsif (defined wantarray) {
403 # we can be called by a relationship helper, which in
404 # turn may be called in void context due to some braindead
405 # overload or whatever else the user decided to be clever
406 # at this particular day. Thus limit the exception to
407 # external code calls only
408 $self->throw_exception ('->search is *not* a mutator, calling it in void context makes no sense')
409 if (caller)[0] !~ /^\QDBIx::Class::/;
419 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
421 =item Return Value: L<$resultset|/search>
425 This method does the same exact thing as search() except it will
426 always return a resultset, even in list context.
433 my $rsrc = $self->result_source;
434 my ($call_cond, $call_attrs);
436 # Special-case handling for (undef, undef) or (undef)
437 # Note that (foo => undef) is valid deprecated syntax
438 @_ = () if not scalar grep { defined $_ } @_;
444 # fish out attrs in the ($condref, $attr) case
445 elsif (@_ == 2 and ( ! defined $_[0] or length ref $_[0] ) ) {
446 ($call_cond, $call_attrs) = @_;
449 $self->throw_exception('Odd number of arguments to search')
453 carp_unique 'search( %condition ) is deprecated, use search( \%condition ) instead'
454 unless $rsrc->result_class->isa('DBIx::Class::CDBICompat');
456 for my $i (0 .. $#_) {
458 $self->throw_exception ('All keys in condition key/value pairs must be plain scalars')
459 if (! defined $_[$i] or length ref $_[$i] );
465 # see if we can keep the cache (no $rs changes)
467 my %safe = (alias => 1, cache => 1);
468 if ( ! grep { !$safe{$_} } keys %$call_attrs and (
471 ref $call_cond eq 'HASH' && ! keys %$call_cond
473 ref $call_cond eq 'ARRAY' && ! @$call_cond
475 $cache = $self->get_cache;
478 my $old_attrs = { %{$self->{attrs}} };
479 my ($old_having, $old_where) = delete @{$old_attrs}{qw(having where)};
481 my $new_attrs = { %$old_attrs };
483 # take care of call attrs (only if anything is changing)
484 if ($call_attrs and keys %$call_attrs) {
486 # copy for _normalize_selection
487 $call_attrs = { %$call_attrs };
489 my @selector_attrs = qw/select as columns cols +select +as +columns include_columns/;
491 # reset the current selector list if new selectors are supplied
492 delete @{$old_attrs}{(@selector_attrs, '_dark_selector')}
493 if grep { exists $call_attrs->{$_} } qw(columns cols select as);
495 # Normalize the new selector list (operates on the passed-in attr structure)
496 # Need to do it on every chain instead of only once on _resolved_attrs, in
497 # order to allow detection of empty vs partial 'as'
498 $call_attrs->{_dark_selector} = $old_attrs->{_dark_selector}
499 if $old_attrs->{_dark_selector};
500 $self->_normalize_selection ($call_attrs);
502 # start with blind overwriting merge, exclude selector attrs
503 $new_attrs = { %{$old_attrs}, %{$call_attrs} };
504 delete @{$new_attrs}{@selector_attrs};
506 for (@selector_attrs) {
507 $new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
508 if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
511 # older deprecated name, use only if {columns} is not there
512 if (my $c = delete $new_attrs->{cols}) {
513 carp_unique( "Resultset attribute 'cols' is deprecated, use 'columns' instead" );
514 if ($new_attrs->{columns}) {
515 carp "Resultset specifies both the 'columns' and the legacy 'cols' attributes - ignoring 'cols'";
518 $new_attrs->{columns} = $c;
523 # join/prefetch use their own crazy merging heuristics
524 foreach my $key (qw/join prefetch/) {
525 $new_attrs->{$key} = $self->_merge_joinpref_attr($old_attrs->{$key}, $call_attrs->{$key})
526 if exists $call_attrs->{$key};
529 # stack binds together
530 $new_attrs->{bind} = [ @{ $old_attrs->{bind} || [] }, @{ $call_attrs->{bind} || [] } ];
534 for ($old_where, $call_cond) {
536 $new_attrs->{where} = $self->_stack_cond (
537 $_, $new_attrs->{where}
542 if (defined $old_having) {
543 $new_attrs->{having} = $self->_stack_cond (
544 $old_having, $new_attrs->{having}
548 my $rs = (ref $self)->new($rsrc, $new_attrs);
550 $rs->set_cache($cache) if ($cache);
555 sub _normalize_selection {
556 my ($self, $attrs) = @_;
559 if ( exists $attrs->{include_columns} ) {
560 carp_unique( "Resultset attribute 'include_columns' is deprecated, use '+columns' instead" );
561 $attrs->{'+columns'} = $self->_merge_attr(
562 $attrs->{'+columns'}, delete $attrs->{include_columns}
566 # columns are always placed first, however
568 # Keep the X vs +X separation until _resolved_attrs time - this allows to
569 # delay the decision on whether to use a default select list ($rsrc->columns)
570 # allowing stuff like the remove_columns helper to work
572 # select/as +select/+as pairs need special handling - the amount of select/as
573 # elements in each pair does *not* have to be equal (think multicolumn
574 # selectors like distinct(foo, bar) ). If the selector is bare (no 'as'
575 # supplied at all) - try to infer the alias, either from the -as parameter
576 # of the selector spec, or use the parameter whole if it looks like a column
577 # name (ugly legacy heuristic). If all fails - leave the selector bare (which
578 # is ok as well), but make sure no more additions to the 'as' chain take place
579 for my $pref ('', '+') {
581 my ($sel, $as) = map {
582 my $key = "${pref}${_}";
584 my $val = [ ref $attrs->{$key} eq 'ARRAY'
586 : $attrs->{$key} || ()
588 delete $attrs->{$key};
592 if (! @$as and ! @$sel ) {
595 elsif (@$as and ! @$sel) {
596 $self->throw_exception(
597 "Unable to handle ${pref}as specification (@$as) without a corresponding ${pref}select"
601 # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
602 # if any @$as has been supplied we assume the user knows what (s)he is doing
603 # and blindly keep stacking up pieces
604 unless ($attrs->{_dark_selector}) {
607 if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
608 push @$as, $_->{-as};
610 # assume any plain no-space, no-parenthesis string to be a column spec
611 # FIXME - this is retarded but is necessary to support shit like 'count(foo)'
612 elsif ( ! ref $_ and $_ =~ /^ [^\s\(\)]+ $/x) {
615 # if all else fails - raise a flag that no more aliasing will be allowed
617 $attrs->{_dark_selector} = {
620 local $Data::Dumper::Indent = 0;
629 elsif (@$as < @$sel) {
630 $self->throw_exception(
631 "Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
634 elsif ($pref and $attrs->{_dark_selector}) {
635 $self->throw_exception(
636 "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
642 $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
643 $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
648 my ($self, $left, $right) = @_;
651 (ref $_ eq 'ARRAY' and !@$_)
653 (ref $_ eq 'HASH' and ! keys %$_)
654 ) and $_ = undef for ($left, $right);
656 # either one of the two undef
657 if ( (defined $left) xor (defined $right) ) {
658 return defined $left ? $left : $right;
661 elsif ( ! defined $left ) {
665 return $self->result_source->schema->storage->_collapse_cond({ -and => [$left, $right] });
669 =head2 search_literal
671 B<CAVEAT>: C<search_literal> is provided for Class::DBI compatibility and
672 should only be used in that context. C<search_literal> is a convenience
673 method. It is equivalent to calling C<< $schema->search(\[]) >>, but if you
674 want to ensure columns are bound correctly, use L</search>.
676 See L<DBIx::Class::Manual::Cookbook/SEARCHING> and
677 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
678 require C<search_literal>.
682 =item Arguments: $sql_fragment, @standalone_bind_values
684 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
688 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
689 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
691 Pass a literal chunk of SQL to be added to the conditional part of the
694 Example of how to use C<search> instead of C<search_literal>
696 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
697 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
702 my ($self, $sql, @bind) = @_;
704 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
707 return $self->search(\[ $sql, map [ {} => $_ ], @bind ], ($attr || () ));
714 =item Arguments: \%columns_values | @pk_values, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
716 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
720 Finds and returns a single row based on supplied criteria. Takes either a
721 hashref with the same format as L</create> (including inference of foreign
722 keys from related objects), or a list of primary key values in the same
723 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
724 declaration on the L</result_source>.
726 In either case an attempt is made to combine conditions already existing on
727 the resultset with the condition passed to this method.
729 To aid with preparing the correct query for the storage you may supply the
730 C<key> attribute, which is the name of a
731 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
732 unique constraint corresponding to the
733 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
734 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
735 to construct a query that satisfies the named unique constraint fully (
736 non-NULL values for each column member of the constraint) an exception is
739 If no C<key> is specified, the search is carried over all unique constraints
740 which are fully defined by the available condition.
742 If no such constraint is found, C<find> currently defaults to a simple
743 C<< search->(\%column_values) >> which may or may not do what you expect.
744 Note that this fallback behavior may be deprecated in further versions. If
745 you need to search with arbitrary conditions - use L</search>. If the query
746 resulting from this fallback produces more than one row, a warning to the
747 effect is issued, though only the first row is constructed and returned as
750 In addition to C<key>, L</find> recognizes and applies standard
751 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
753 Note that if you have extra concerns about the correctness of the resulting
754 query you need to specify the C<key> attribute and supply the entire condition
755 as an argument to find (since it is not always possible to perform the
756 combination of the resultset condition with the supplied one, especially if
757 the resultset condition contains literal sql).
759 For example, to find a row by its primary key:
761 my $cd = $schema->resultset('CD')->find(5);
763 You can also find a row by a specific unique constraint:
765 my $cd = $schema->resultset('CD')->find(
767 artist => 'Massive Attack',
768 title => 'Mezzanine',
770 { key => 'cd_artist_title' }
773 See also L</find_or_create> and L</update_or_create>.
779 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
781 my $rsrc = $self->result_source;
784 if (exists $attrs->{key}) {
785 $constraint_name = defined $attrs->{key}
787 : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
791 # Parse out the condition from input
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
816 for my $key (keys %$call_cond) {
818 length ref($call_cond->{$key})
820 my $relinfo = $rsrc->relationship_info($key)
822 # implicitly skip has_many's (likely MC)
823 (ref (my $val = delete $call_cond->{$key}) ne 'ARRAY' )
825 my ($rel_cond, $crosstable) = $rsrc->_resolve_condition(
826 $relinfo->{cond}, $val, $key, $key
829 $self->throw_exception("Complex condition via relationship '$key' is unsupported in find()")
830 if $crosstable or ref($rel_cond) ne 'HASH';
832 # supplement condition
833 # relationship conditions take precedence (?)
834 @{$call_cond}{keys %$rel_cond} = values %$rel_cond;
838 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
840 if (defined $constraint_name) {
841 $final_cond = $self->_qualify_cond_columns (
843 $rsrc->_minimal_valueset_satisfying_constraint(
844 constraint_name => $constraint_name,
845 values => ($self->_merge_with_rscond($call_cond))[0],
852 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
853 # This means that we got here after a merger of relationship conditions
854 # in ::Relationship::Base::search_related (the row method), and furthermore
855 # the relationship is of the 'single' type. This means that the condition
856 # provided by the relationship (already attached to $self) is sufficient,
857 # as there can be only one row in the database that would satisfy the
861 my (@unique_queries, %seen_column_combinations, $ci, @fc_exceptions);
863 # no key was specified - fall down to heuristics mode:
864 # run through all unique queries registered on the resultset, and
865 # 'OR' all qualifying queries together
867 # always start from 'primary' if it exists at all
868 for my $c_name ( sort {
870 : $b eq 'primary' ? 1
872 } $rsrc->unique_constraint_names) {
874 next if $seen_column_combinations{
875 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
879 push @unique_queries, $self->_qualify_cond_columns(
880 $rsrc->_minimal_valueset_satisfying_constraint(
881 constraint_name => $c_name,
882 values => ($self->_merge_with_rscond($call_cond))[0],
883 columns_info => ($ci ||= $rsrc->columns_info),
889 push @fc_exceptions, $_ if $_ =~ /\bFilterColumn\b/;
894 @unique_queries ? \@unique_queries
895 : @fc_exceptions ? $self->throw_exception(join "; ", map { $_ =~ /(.*) at .+ line \d+$/s } @fc_exceptions )
896 : $self->_non_unique_find_fallback ($call_cond, $attrs)
900 # Run the query, passing the result_class since it should propagate for find
901 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
902 if ($rs->_resolved_attrs->{collapse}) {
904 carp "Query returned more than one row" if $rs->next;
912 # This is a stop-gap method as agreed during the discussion on find() cleanup:
913 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
915 # It is invoked when find() is called in legacy-mode with insufficiently-unique
916 # condition. It is provided for overrides until a saner way forward is devised
918 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
919 # the road. Please adjust your tests accordingly to catch this situation early
920 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
922 # The method will not be removed without an adequately complete replacement
923 # for strict-mode enforcement
924 sub _non_unique_find_fallback {
925 my ($self, $cond, $attrs) = @_;
927 return $self->_qualify_cond_columns(
929 exists $attrs->{alias}
931 : $self->{attrs}{alias}
936 sub _qualify_cond_columns {
937 my ($self, $cond, $alias) = @_;
939 my %aliased = %$cond;
940 for (keys %aliased) {
941 $aliased{"$alias.$_"} = delete $aliased{$_}
948 sub _build_unique_cond {
950 '_build_unique_cond is a private method, and moreover is about to go '
951 . 'away. Please contact the development team at %s if you believe you '
952 . 'have a genuine use for this method, in order to discuss alternatives.',
953 DBIx::Class::_ENV_::HELP_URL,
956 my ($self, $constraint_name, $cond, $croak_on_null) = @_;
958 $self->result_source->_minimal_valueset_satisfying_constraint(
959 constraint_name => $constraint_name,
961 carp_on_nulls => !$croak_on_null
965 =head2 search_related
969 =item Arguments: $rel_name, $cond?, L<\%attrs?|/ATTRIBUTES>
971 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
975 $new_rs = $cd_rs->search_related('artist', {
979 Searches the specified relationship, optionally specifying a condition and
980 attributes for matching records. See L</ATTRIBUTES> for more information.
982 In list context, C<< ->all() >> is called implicitly on the resultset, thus
983 returning a list of result objects instead. To avoid that, use L</search_related_rs>.
985 See also L</search_related_rs>.
990 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
991 return shift->related_resultset(shift)->search(@_);
994 =head2 search_related_rs
996 This method works exactly the same as search_related, except that
997 it guarantees a resultset, even in list context.
1001 sub search_related_rs {
1002 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1003 return shift->related_resultset(shift)->search_rs(@_);
1010 =item Arguments: none
1012 =item Return Value: L<$cursor|DBIx::Class::Cursor>
1016 Returns a storage-driven cursor to the given resultset. See
1017 L<DBIx::Class::Cursor> for more information.
1024 return $self->{cursor} ||= do {
1025 my $attrs = $self->_resolved_attrs;
1026 $self->result_source->schema->storage->select(
1027 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
1036 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1038 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1042 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1044 Inflates the first result without creating a cursor if the resultset has
1045 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1048 While this method can take an optional search condition (just like L</search>)
1049 being a fast-code-path it does not recognize search attributes. If you need to
1050 add extra joins or similar, call L</search> and then chain-call L</single> on the
1051 L<DBIx::Class::ResultSet> returned.
1057 As of 0.08100, this method enforces the assumption that the preceding
1058 query returns only one row. If more than one row is returned, you will receive
1061 Query returned more than one row
1063 In this case, you should be using L</next> or L</find> instead, or if you really
1064 know what you are doing, use the L</rows> attribute to explicitly limit the size
1067 This method will also throw an exception if it is called on a resultset prefetching
1068 has_many, as such a prefetch implies fetching multiple rows from the database in
1069 order to assemble the resulting object.
1076 my ($self, $where) = @_;
1078 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1081 my $attrs = { %{$self->_resolved_attrs} };
1083 $self->throw_exception(
1084 'single() can not be used on resultsets collapsing a has_many. Use find( \%cond ) or next() instead'
1085 ) if $attrs->{collapse};
1088 if (defined $attrs->{where}) {
1091 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1092 $where, delete $attrs->{where} ]
1095 $attrs->{where} = $where;
1099 my $data = [ $self->result_source->schema->storage->select_single(
1100 $attrs->{from}, $attrs->{select},
1101 $attrs->{where}, $attrs
1104 return undef unless @$data;
1105 $self->{_stashed_rows} = [ $data ];
1106 $self->_construct_results->[0];
1113 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1115 =item Return Value: L<$resultsetcolumn|DBIx::Class::ResultSetColumn>
1119 my $max_length = $rs->get_column('length')->max;
1121 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1126 DBIx::Class::ResultSetColumn->new(@_);
1133 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1135 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1139 # WHERE title LIKE '%blue%'
1140 $cd_rs = $rs->search_like({ title => '%blue%'});
1142 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1143 that this is simply a convenience method retained for ex Class::DBI users.
1144 You most likely want to use L</search> with specific operators.
1146 For more information, see L<DBIx::Class::Manual::Cookbook>.
1148 This method is deprecated and will be removed in 0.09. Use L<search()|/search>
1149 instead. An example conversion is:
1151 ->search_like({ foo => 'bar' });
1155 ->search({ foo => { like => 'bar' } });
1162 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1163 .' Instead use ->search({ x => { -like => "y%" } })'
1164 .' (note the outer pair of {}s - they are important!)'
1166 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1167 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1168 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1169 return $class->search($query, { %$attrs });
1176 =item Arguments: $first, $last
1178 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1182 Returns a resultset or object list representing a subset of elements from the
1183 resultset slice is called on. Indexes are from 0, i.e., to get the first
1184 three records, call:
1186 my ($one, $two, $three) = $rs->slice(0, 2);
1191 my ($self, $min, $max) = @_;
1192 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1193 $attrs->{offset} = $self->{attrs}{offset} || 0;
1194 $attrs->{offset} += $min;
1195 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1196 return $self->search(undef, $attrs);
1203 =item Arguments: none
1205 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1209 Returns the next element in the resultset (C<undef> is there is none).
1211 Can be used to efficiently iterate over records in the resultset:
1213 my $rs = $schema->resultset('CD')->search;
1214 while (my $cd = $rs->next) {
1218 Note that you need to store the resultset object, and call C<next> on it.
1219 Calling C<< resultset('Table')->next >> repeatedly will always return the
1220 first record from the resultset.
1227 if (my $cache = $self->get_cache) {
1228 $self->{all_cache_position} ||= 0;
1229 return $cache->[$self->{all_cache_position}++];
1232 if ($self->{attrs}{cache}) {
1233 delete $self->{pager};
1234 $self->{all_cache_position} = 1;
1235 return ($self->all)[0];
1238 return shift(@{$self->{_stashed_results}}) if @{ $self->{_stashed_results}||[] };
1240 $self->{_stashed_results} = $self->_construct_results
1243 return shift @{$self->{_stashed_results}};
1246 # Constructs as many results as it can in one pass while respecting
1247 # cursor laziness. Several modes of operation:
1249 # * Always builds everything present in @{$self->{_stashed_rows}}
1250 # * If called with $fetch_all true - pulls everything off the cursor and
1251 # builds all result structures (or objects) in one pass
1252 # * If $self->_resolved_attrs->{collapse} is true, checks the order_by
1253 # and if the resultset is ordered properly by the left side:
1254 # * Fetches stuff off the cursor until the "master object" changes,
1255 # and saves the last extra row (if any) in @{$self->{_stashed_rows}}
1257 # * Just fetches, and collapses/constructs everything as if $fetch_all
1258 # was requested (there is no other way to collapse except for an
1260 # * If no collapse is requested - just get the next row, construct and
1262 sub _construct_results {
1263 my ($self, $fetch_all) = @_;
1265 my $rsrc = $self->result_source;
1266 my $attrs = $self->_resolved_attrs;
1271 ! $attrs->{order_by}
1275 my @pcols = $rsrc->primary_columns
1277 # default order for collapsing unless the user asked for something
1278 $attrs->{order_by} = [ map { join '.', $attrs->{alias}, $_} @pcols ];
1279 $attrs->{_ordered_for_collapse} = 1;
1280 $attrs->{_order_is_artificial} = 1;
1283 # this will be used as both initial raw-row collector AND as a RV of
1284 # _construct_results. Not regrowing the array twice matters a lot...
1285 # a surprising amount actually
1286 my $rows = delete $self->{_stashed_rows};
1288 my $cursor; # we may not need one at all
1290 my $did_fetch_all = $fetch_all;
1293 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1294 $rows = [ ($rows ? @$rows : ()), $self->cursor->all ];
1296 elsif( $attrs->{collapse} ) {
1298 # a cursor will need to be closed over in case of collapse
1299 $cursor = $self->cursor;
1301 $attrs->{_ordered_for_collapse} = (
1307 ->_extract_colinfo_of_stable_main_source_order_by_portion($attrs)
1309 ) unless defined $attrs->{_ordered_for_collapse};
1311 if (! $attrs->{_ordered_for_collapse}) {
1314 # instead of looping over ->next, use ->all in stealth mode
1315 # *without* calling a ->reset afterwards
1316 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1317 if (! $cursor->{_done}) {
1318 $rows = [ ($rows ? @$rows : ()), $cursor->all ];
1319 $cursor->{_done} = 1;
1324 if (! $did_fetch_all and ! @{$rows||[]} ) {
1325 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1326 $cursor ||= $self->cursor;
1327 if (scalar (my @r = $cursor->next) ) {
1332 return undef unless @{$rows||[]};
1334 # sanity check - people are too clever for their own good
1335 if ($attrs->{collapse} and my $aliastypes = $attrs->{_last_sqlmaker_alias_map} ) {
1337 my $multiplied_selectors;
1338 for my $sel_alias ( grep { $_ ne $attrs->{alias} } keys %{ $aliastypes->{selecting} } ) {
1340 $aliastypes->{multiplying}{$sel_alias}
1342 $aliastypes->{premultiplied}{$sel_alias}
1344 $multiplied_selectors->{$_} = 1 for values %{$aliastypes->{selecting}{$sel_alias}{-seen_columns}}
1348 for my $i (0 .. $#{$attrs->{as}} ) {
1349 my $sel = $attrs->{select}[$i];
1351 if (ref $sel eq 'SCALAR') {
1354 elsif( ref $sel eq 'REF' and ref $$sel eq 'ARRAY' ) {
1358 $self->throw_exception(
1359 'Result collapse not possible - selection from a has_many source redirected to the main object'
1360 ) if ($multiplied_selectors->{$sel} and $attrs->{as}[$i] !~ /\./);
1364 # hotspot - skip the setter
1365 my $res_class = $self->_result_class;
1367 my $inflator_cref = $self->{_result_inflator}{cref} ||= do {
1368 $res_class->can ('inflate_result')
1369 or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
1372 my $infmap = $attrs->{as};
1374 $self->{_result_inflator}{is_core_row} = ( (
1377 ( \&DBIx::Class::Row::inflate_result || die "No ::Row::inflate_result() - can't happen" )
1378 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_core_row};
1380 $self->{_result_inflator}{is_hri} = ( (
1381 ! $self->{_result_inflator}{is_core_row}
1383 $inflator_cref == \&DBIx::Class::ResultClass::HashRefInflator::inflate_result
1384 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_hri};
1387 if ($attrs->{_simple_passthrough_construction}) {
1388 # construct a much simpler array->hash folder for the one-table HRI cases right here
1389 if ($self->{_result_inflator}{is_hri}) {
1390 for my $r (@$rows) {
1391 $r = { map { $infmap->[$_] => $r->[$_] } 0..$#$infmap };
1394 # FIXME SUBOPTIMAL this is a very very very hot spot
1395 # while rather optimal we can *still* do much better, by
1396 # building a smarter Row::inflate_result(), and
1397 # switch to feeding it data via a much leaner interface
1399 # crude unscientific benchmarking indicated the shortcut eval is not worth it for
1400 # this particular resultset size
1401 elsif ( $self->{_result_inflator}{is_core_row} and @$rows < 60 ) {
1402 for my $r (@$rows) {
1403 $r = $inflator_cref->($res_class, $rsrc, { map { $infmap->[$_] => $r->[$_] } (0..$#$infmap) } );
1408 ( $self->{_result_inflator}{is_core_row}
1409 ? '$_ = $inflator_cref->($res_class, $rsrc, { %s }) for @$rows'
1410 # a custom inflator may be a multiplier/reductor - put it in direct list ctx
1411 : '@$rows = map { $inflator_cref->($res_class, $rsrc, { %s } ) } @$rows'
1413 ( join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap ) )
1419 $self->{_result_inflator}{is_hri} ? 'hri'
1420 : $self->{_result_inflator}{is_core_row} ? 'classic_pruning'
1421 : 'classic_nonpruning'
1424 unless( $self->{_row_parser}{$parser_type}{cref} ) {
1426 # $args and $attrs to _mk_row_parser are separated to delineate what is
1427 # core collapser stuff and what is dbic $rs specific
1428 $self->{_row_parser}{$parser_type}{src} = $rsrc->_mk_row_parser({
1429 inflate_map => $infmap,
1430 collapse => $attrs->{collapse},
1431 premultiplied => $attrs->{_main_source_premultiplied},
1432 hri_style => $self->{_result_inflator}{is_hri},
1433 prune_null_branches => $self->{_result_inflator}{is_hri} || $self->{_result_inflator}{is_core_row},
1436 $self->{_row_parser}{$parser_type}{cref} = do {
1437 package # hide form PAUSE
1438 DBIx::Class::__GENERATED_ROW_PARSER__;
1440 eval $self->{_row_parser}{$parser_type}{src};
1444 # this needs to close over the *current* cursor, hence why it is not cached above
1445 my $next_cref = ($did_fetch_all or ! $attrs->{collapse})
1448 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1449 my @r = $cursor->next or return;
1454 $self->{_row_parser}{$parser_type}{cref}->(
1457 ( $self->{_stashed_rows} = [] ),
1458 ( my $null_violations = {} ),
1461 $self->throw_exception(
1462 'Collapse aborted - the following columns are declared (or defaulted to) '
1463 . 'non-nullable within DBIC but NULLs were retrieved from storage: '
1464 . join( ', ', map { "'$infmap->[$_]'" } sort { $a <=> $b } keys %$null_violations )
1465 . ' within data row ' . dump_value({
1468 ( ! defined $self->{_stashed_rows}[0][$_] or length $self->{_stashed_rows}[0][$_] < 50 )
1469 ? $self->{_stashed_rows}[0][$_]
1470 : substr( $self->{_stashed_rows}[0][$_], 0, 50 ) . '...'
1471 } 0 .. $#{$self->{_stashed_rows}[0]}
1473 ) if keys %$null_violations;
1475 # simple in-place substitution, does not regrow $rows
1476 if ($self->{_result_inflator}{is_core_row}) {
1477 $_ = $inflator_cref->($res_class, $rsrc, @$_) for @$rows
1479 # Special-case multi-object HRI - there is no $inflator_cref pass at all
1480 elsif ( ! $self->{_result_inflator}{is_hri} ) {
1481 # the inflator may be a multiplier/reductor - put it in list ctx
1482 @$rows = map { $inflator_cref->($res_class, $rsrc, @$_) } @$rows;
1486 # The @$rows check seems odd at first - why wouldn't we want to warn
1487 # regardless? The issue is things like find() etc, where the user
1488 # *knows* only one result will come back. In these cases the ->all
1489 # is not a pessimization, but rather something we actually want
1491 'Unable to properly collapse has_many results in iterator mode due '
1492 . 'to order criteria - performed an eager cursor slurp underneath. '
1493 . 'Consider using ->all() instead'
1494 ) if ( ! $fetch_all and @$rows > 1 );
1499 =head2 result_source
1503 =item Arguments: L<$result_source?|DBIx::Class::ResultSource>
1505 =item Return Value: L<$result_source|DBIx::Class::ResultSource>
1509 An accessor for the primary ResultSource object from which this ResultSet
1516 =item Arguments: $result_class?
1518 =item Return Value: $result_class
1522 An accessor for the class to use when creating result objects. Defaults to
1523 C<< result_source->result_class >> - which in most cases is the name of the
1524 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1526 Note that changing the result_class will also remove any components
1527 that were originally loaded in the source class via
1528 L<load_components|Class::C3::Componentised/load_components( @comps )>.
1529 Any overloaded methods in the original source class will not run.
1534 my ($self, $result_class) = @_;
1535 if ($result_class) {
1537 # don't fire this for an object
1538 $self->ensure_class_loaded($result_class)
1539 unless ref($result_class);
1541 if ($self->get_cache) {
1542 carp_unique('Changing the result_class of a ResultSet instance with cached results is a noop - the cache contents will not be altered');
1544 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1545 elsif ($self->{cursor} && $self->{cursor}{_pos}) {
1546 $self->throw_exception('Changing the result_class of a ResultSet instance with an active cursor is not supported');
1549 $self->_result_class($result_class);
1551 delete $self->{_result_inflator};
1553 $self->_result_class;
1560 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1562 =item Return Value: $count
1566 Performs an SQL C<COUNT> with the same query as the resultset was built
1567 with to find the number of elements. Passing arguments is equivalent to
1568 C<< $rs->search ($cond, \%attrs)->count >>
1574 return $self->search(@_)->count if @_ and defined $_[0];
1575 return scalar @{ $self->get_cache } if $self->get_cache;
1577 my $attrs = { %{ $self->_resolved_attrs } };
1579 # this is a little optimization - it is faster to do the limit
1580 # adjustments in software, instead of a subquery
1581 my ($rows, $offset) = delete @{$attrs}{qw/rows offset/};
1584 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1585 $crs = $self->_count_subq_rs ($attrs);
1588 $crs = $self->_count_rs ($attrs);
1590 my $count = $crs->next;
1592 $count -= $offset if $offset;
1593 $count = $rows if $rows and $rows < $count;
1594 $count = 0 if ($count < 0);
1603 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1605 =item Return Value: L<$count_rs|DBIx::Class::ResultSetColumn>
1609 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1610 This can be very handy for subqueries:
1612 ->search( { amount => $some_rs->count_rs->as_query } )
1614 As with regular resultsets the SQL query will be executed only after
1615 the resultset is accessed via L</next> or L</all>. That would return
1616 the same single value obtainable via L</count>.
1622 return $self->search(@_)->count_rs if @_;
1624 # this may look like a lack of abstraction (count() does about the same)
1625 # but in fact an _rs *must* use a subquery for the limits, as the
1626 # software based limiting can not be ported if this $rs is to be used
1627 # in a subquery itself (i.e. ->as_query)
1628 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1629 return $self->_count_subq_rs($self->{_attrs});
1632 return $self->_count_rs($self->{_attrs});
1637 # returns a ResultSetColumn object tied to the count query
1640 my ($self, $attrs) = @_;
1642 my $rsrc = $self->result_source;
1644 my $tmp_attrs = { %$attrs };
1645 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1646 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1648 # overwrite the selector (supplied by the storage)
1649 $rsrc->resultset_class->new($rsrc, {
1651 select => $rsrc->schema->storage->_count_select ($rsrc, $attrs),
1653 })->get_column ('count');
1657 # same as above but uses a subquery
1659 sub _count_subq_rs {
1660 my ($self, $attrs) = @_;
1662 my $rsrc = $self->result_source;
1664 my $sub_attrs = { %$attrs };
1665 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1666 delete @{$sub_attrs}{qw/collapse columns as select order_by for/};
1668 # if we multi-prefetch we group_by something unique, as this is what we would
1669 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1670 if ( $attrs->{collapse} ) {
1671 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1672 $rsrc->_identifying_column_set || $self->throw_exception(
1673 'Unable to construct a unique group_by criteria properly collapsing the '
1674 . 'has_many prefetch before count()'
1679 # Calculate subquery selector
1680 if (my $g = $sub_attrs->{group_by}) {
1682 my $sql_maker = $rsrc->schema->storage->sql_maker;
1684 # necessary as the group_by may refer to aliased functions
1686 for my $sel (@{$attrs->{select}}) {
1687 $sel_index->{$sel->{-as}} = $sel
1688 if (ref $sel eq 'HASH' and $sel->{-as});
1691 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1692 # also look for named aggregates referred in the having clause
1693 # having often contains scalarrefs - thus parse it out entirely
1695 if ($attrs->{having}) {
1696 local $sql_maker->{having_bind};
1697 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1698 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1699 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1700 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1701 # if we don't unset it we screw up retarded but unfortunately working
1702 # 'MAX(foo.bar)' => { '>', 3 }
1703 $sql_maker->{name_sep} = '';
1706 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1708 my $having_sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1711 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1712 # and if all fails for an utterly naive quoted scalar-with-function
1713 while ($having_sql =~ /
1714 $rquote $sep $lquote (.+?) $rquote
1716 [\s,] \w+ \. (\w+) [\s,]
1718 [\s,] $lquote (.+?) $rquote [\s,]
1720 my $part = $1 || $2 || $3; # one of them matched if we got here
1721 unless ($seen_having{$part}++) {
1728 my $colpiece = $sel_index->{$_} || $_;
1730 # unqualify join-based group_by's. Arcane but possible query
1731 # also horrible horrible hack to alias a column (not a func.)
1732 # (probably need to introduce SQLA syntax)
1733 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1736 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1738 push @{$sub_attrs->{select}}, $colpiece;
1742 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1743 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1746 return $rsrc->resultset_class
1747 ->new ($rsrc, $sub_attrs)
1749 ->search ({}, { columns => { count => $rsrc->schema->storage->_count_select ($rsrc, $attrs) } })
1750 ->get_column ('count');
1754 =head2 count_literal
1756 B<CAVEAT>: C<count_literal> is provided for Class::DBI compatibility and
1757 should only be used in that context. See L</search_literal> for further info.
1761 =item Arguments: $sql_fragment, @standalone_bind_values
1763 =item Return Value: $count
1767 Counts the results in a literal query. Equivalent to calling L</search_literal>
1768 with the passed arguments, then L</count>.
1773 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1774 shift->search_literal(@_)->count
1781 =item Arguments: none
1783 =item Return Value: L<@result_objs|DBIx::Class::Manual::ResultClass>
1787 Returns all elements in the resultset.
1794 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1797 delete @{$self}{qw/_stashed_rows _stashed_results/};
1799 if (my $c = $self->get_cache) {
1803 $self->cursor->reset;
1805 my $objs = $self->_construct_results('fetch_all') || [];
1807 $self->set_cache($objs) if $self->{attrs}{cache};
1816 =item Arguments: none
1818 =item Return Value: $self
1822 Resets the resultset's cursor, so you can iterate through the elements again.
1823 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1831 delete @{$self}{qw/_stashed_rows _stashed_results/};
1832 $self->{all_cache_position} = 0;
1833 $self->cursor->reset;
1841 =item Arguments: none
1843 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1847 L<Resets|/reset> the resultset (causing a fresh query to storage) and returns
1848 an object for the first result (or C<undef> if the resultset is empty).
1853 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1854 return $_[0]->reset->next;
1860 # Determines whether and what type of subquery is required for the $rs operation.
1861 # If grouping is necessary either supplies its own, or verifies the current one
1862 # After all is done delegates to the proper storage method.
1864 sub _rs_update_delete {
1865 my ($self, $op, $values) = @_;
1867 my $rsrc = $self->result_source;
1868 my $storage = $rsrc->schema->storage;
1870 my $attrs = { %{$self->_resolved_attrs} };
1872 my $join_classifications;
1873 my ($existing_group_by) = delete @{$attrs}{qw(group_by _grouped_by_distinct)};
1875 # do we need a subquery for any reason?
1877 defined $existing_group_by
1879 # if {from} is unparseable wrap a subq
1880 ref($attrs->{from}) ne 'ARRAY'
1882 # limits call for a subq
1883 $self->_has_resolved_attr(qw/rows offset/)
1886 # simplify the joinmap, so we can further decide if a subq is necessary
1887 if (!$needs_subq and @{$attrs->{from}} > 1) {
1889 ($attrs->{from}, $join_classifications) =
1890 $storage->_prune_unused_joins ($attrs);
1892 # any non-pruneable non-local restricting joins imply subq
1893 $needs_subq = grep { $_ ne $attrs->{alias} } keys %{ $join_classifications->{restricting} || {} };
1896 # check if the head is composite (by now all joins are thrown out unless $needs_subq)
1898 (ref $attrs->{from}[0]) ne 'HASH'
1900 ref $attrs->{from}[0]{ $attrs->{from}[0]{-alias} }
1904 # do we need anything like a subquery?
1905 if (! $needs_subq) {
1906 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1907 # a condition containing 'me' or other table prefixes will not work
1908 # at all. Tell SQLMaker to dequalify idents via a gross hack.
1910 my $sqla = $rsrc->schema->storage->sql_maker;
1911 local $sqla->{_dequalify_idents} = 1;
1912 \[ $sqla->_recurse_where($self->{cond}) ];
1916 # we got this far - means it is time to wrap a subquery
1917 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1919 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1925 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1926 delete $attrs->{$_} for qw/select as collapse/;
1927 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1929 # this will be consumed by the pruner waaaaay down the stack
1930 $attrs->{_force_prune_multiplying_joins} = 1;
1932 my $subrs = (ref $self)->new($rsrc, $attrs);
1934 if (@$idcols == 1) {
1935 $cond = { $idcols->[0] => { -in => $subrs->as_query } };
1937 elsif ($storage->_use_multicolumn_in) {
1938 # no syntax for calling this properly yet
1939 # !!! EXPERIMENTAL API !!! WILL CHANGE !!!
1940 $cond = $storage->sql_maker->_where_op_multicolumn_in (
1941 $idcols, # how do I convey a list of idents...? can binds reside on lhs?
1946 # if all else fails - get all primary keys and operate over a ORed set
1947 # wrap in a transaction for consistency
1948 # this is where the group_by/multiplication starts to matter
1952 # we do not need to check pre-multipliers, since if the premulti is there, its
1953 # parent (who is multi) will be there too
1954 keys %{ $join_classifications->{multiplying} || {} }
1956 # make sure if there is a supplied group_by it matches the columns compiled above
1957 # perfectly. Anything else can not be sanely executed on most databases so croak
1958 # right then and there
1959 if ($existing_group_by) {
1960 my @current_group_by = map
1961 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1966 join ("\x00", sort @current_group_by)
1968 join ("\x00", sort @{$attrs->{columns}} )
1970 $self->throw_exception (
1971 "You have just attempted a $op operation on a resultset which does group_by"
1972 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1973 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1974 . ' kind of queries. Please retry the operation with a modified group_by or'
1975 . ' without using one at all.'
1980 $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
1983 $guard = $storage->txn_scope_guard;
1985 for my $row ($subrs->cursor->all) {
1987 { $idcols->[$_] => $row->[$_] }
1994 my $res = $cond ? $storage->$op (
1996 $op eq 'update' ? $values : (),
2000 $guard->commit if $guard;
2009 =item Arguments: \%values
2011 =item Return Value: $underlying_storage_rv
2015 Sets the specified columns in the resultset to the supplied values in a
2016 single query. Note that this will not run any accessor/set_column/update
2017 triggers, nor will it update any result object instances derived from this
2018 resultset (this includes the contents of the L<resultset cache|/set_cache>
2019 if any). See L</update_all> if you need to execute any on-update
2020 triggers or cascades defined either by you or a
2021 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2023 The return value is a pass through of what the underlying
2024 storage backend returned, and may vary. See L<DBI/execute> for the most
2029 Note that L</update> does not process/deflate any of the values passed in.
2030 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
2031 ensure manually that any value passed to this method will stringify to
2032 something the RDBMS knows how to deal with. A notable example is the
2033 handling of L<DateTime> objects, for more info see:
2034 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
2039 my ($self, $values) = @_;
2040 $self->throw_exception('Values for update must be a hash')
2041 unless ref $values eq 'HASH';
2043 return $self->_rs_update_delete ('update', $values);
2050 =item Arguments: \%values
2052 =item Return Value: 1
2056 Fetches all objects and updates them one at a time via
2057 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
2058 triggers, while L</update> will not.
2063 my ($self, $values) = @_;
2064 $self->throw_exception('Values for update_all must be a hash')
2065 unless ref $values eq 'HASH';
2067 my $guard = $self->result_source->schema->txn_scope_guard;
2068 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
2077 =item Arguments: none
2079 =item Return Value: $underlying_storage_rv
2083 Deletes the rows matching this resultset in a single query. Note that this
2084 will not run any delete triggers, nor will it alter the
2085 L<in_storage|DBIx::Class::Row/in_storage> status of any result object instances
2086 derived from this resultset (this includes the contents of the
2087 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
2088 execute any on-delete triggers or cascades defined either by you or a
2089 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2091 The return value is a pass through of what the underlying storage backend
2092 returned, and may vary. See L<DBI/execute> for the most common case.
2098 $self->throw_exception('delete does not accept any arguments')
2101 return $self->_rs_update_delete ('delete');
2108 =item Arguments: none
2110 =item Return Value: 1
2114 Fetches all objects and deletes them one at a time via
2115 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2116 triggers, while L</delete> will not.
2122 $self->throw_exception('delete_all does not accept any arguments')
2125 my $guard = $self->result_source->schema->txn_scope_guard;
2126 $_->delete for $self->all;
2135 =item Arguments: [ \@column_list, \@row_values+ ] | [ \%col_data+ ]
2137 =item Return Value: L<\@result_objects|DBIx::Class::Manual::ResultClass> (scalar context) | L<@result_objects|DBIx::Class::Manual::ResultClass> (list context)
2141 Accepts either an arrayref of hashrefs or alternatively an arrayref of
2148 The context of this method call has an important effect on what is
2149 submitted to storage. In void context data is fed directly to fastpath
2150 insertion routines provided by the underlying storage (most often
2151 L<DBI/execute_for_fetch>), bypassing the L<new|DBIx::Class::Row/new> and
2152 L<insert|DBIx::Class::Row/insert> calls on the
2153 L<Result|DBIx::Class::Manual::ResultClass> class, including any
2154 augmentation of these methods provided by components. For example if you
2155 are using something like L<DBIx::Class::UUIDColumns> to create primary
2156 keys for you, you will find that your PKs are empty. In this case you
2157 will have to explicitly force scalar or list context in order to create
2162 In non-void (scalar or list) context, this method is simply a wrapper
2163 for L</create>. Depending on list or scalar context either a list of
2164 L<Result|DBIx::Class::Manual::ResultClass> objects or an arrayref
2165 containing these objects is returned.
2167 When supplying data in "arrayref of arrayrefs" invocation style, the
2168 first element should be a list of column names and each subsequent
2169 element should be a data value in the earlier specified column order.
2172 $schema->resultset("Artist")->populate([
2173 [ qw( artistid name ) ],
2174 [ 100, 'A Formally Unknown Singer' ],
2175 [ 101, 'A singer that jumped the shark two albums ago' ],
2176 [ 102, 'An actually cool singer' ],
2179 For the arrayref of hashrefs style each hashref should be a structure
2180 suitable for passing to L</create>. Multi-create is also permitted with
2183 $schema->resultset("Artist")->populate([
2184 { artistid => 4, name => 'Manufactured Crap', cds => [
2185 { title => 'My First CD', year => 2006 },
2186 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2189 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2190 { title => 'My parents sold me to a record company', year => 2005 },
2191 { title => 'Why Am I So Ugly?', year => 2006 },
2192 { title => 'I Got Surgery and am now Popular', year => 2007 }
2197 If you attempt a void-context multi-create as in the example above (each
2198 Artist also has the related list of CDs), and B<do not> supply the
2199 necessary autoinc foreign key information, this method will proxy to the
2200 less efficient L</create>, and then throw the Result objects away. In this
2201 case there are obviously no benefits to using this method over L</create>.
2208 # this is naive and just a quick check
2209 # the types will need to be checked more thoroughly when the
2210 # multi-source populate gets added
2212 ref $_[0] eq 'ARRAY'
2214 ( @{$_[0]} or return )
2216 ( ref $_[0][0] eq 'HASH' or ref $_[0][0] eq 'ARRAY' )
2219 ) or $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2221 # FIXME - no cref handling
2222 # At this point assume either hashes or arrays
2224 my $rsrc = $self->result_source;
2226 if(defined wantarray) {
2227 my (@results, $guard);
2229 if (ref $data->[0] eq 'ARRAY') {
2230 # column names only, nothing to do
2231 return if @$data == 1;
2233 $guard = $rsrc->schema->storage->txn_scope_guard
2237 { my $vals = $_; $self->new_result({ map { $data->[0][$_] => $vals->[$_] } 0..$#{$data->[0]} })->insert }
2238 @{$data}[1 .. $#$data]
2243 $guard = $rsrc->schema->storage->txn_scope_guard
2246 @results = map { $self->new_result($_)->insert } @$data;
2249 $guard->commit if $guard;
2250 return wantarray ? @results : \@results;
2253 # we have to deal with *possibly incomplete* related data
2254 # this means we have to walk the data structure twice
2255 # whether we want this or not
2256 # jnap, I hate you ;)
2257 my $rel_info = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2259 my ($colinfo, $colnames, $slices_with_rels);
2263 for my $i (0 .. $#$data) {
2265 my $current_slice_seen_rel_infos;
2267 ### Determine/Supplement collists
2268 ### BEWARE - This is a hot piece of code, a lot of weird idioms were used
2269 if( ref $data->[$i] eq 'ARRAY' ) {
2271 # positional(!) explicit column list
2273 # column names only, nothing to do
2274 return if @$data == 1;
2276 $colinfo->{$data->[0][$_]} = { pos => $_, name => $data->[0][$_] } and push @$colnames, $data->[0][$_]
2277 for 0 .. $#{$data->[0]};
2284 for (values %$colinfo) {
2285 if ($_->{is_rel} ||= (
2286 $rel_info->{$_->{name}}
2289 ref $data->[$i][$_->{pos}] eq 'ARRAY'
2291 ref $data->[$i][$_->{pos}] eq 'HASH'
2293 ( defined blessed $data->[$i][$_->{pos}] and $data->[$i][$_->{pos}]->isa('DBIx::Class::Row') )
2299 # moar sanity check... sigh
2300 for ( ref $data->[$i][$_->{pos}] eq 'ARRAY' ? @{$data->[$i][$_->{pos}]} : $data->[$i][$_->{pos}] ) {
2301 if ( defined blessed $_ and $_->isa('DBIx::Class::Row' ) ) {
2302 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2303 return my $throwaway = $self->populate(@_);
2307 push @$current_slice_seen_rel_infos, $rel_info->{$_->{name}};
2312 if ($current_slice_seen_rel_infos) {
2313 push @$slices_with_rels, { map { $colnames->[$_] => $data->[$i][$_] } 0 .. $#$colnames };
2315 # this is needed further down to decide whether or not to fallback to create()
2316 $colinfo->{$colnames->[$_]}{seen_null} ||= ! defined $data->[$i][$_]
2317 for 0 .. $#$colnames;
2320 elsif( ref $data->[$i] eq 'HASH' ) {
2322 for ( sort keys %{$data->[$i]} ) {
2324 $colinfo->{$_} ||= do {
2326 $self->throw_exception("Column '$_' must be present in supplied explicit column list")
2327 if $data_start; # it will be 0 on AoH, 1 on AoA
2329 push @$colnames, $_;
2332 { pos => $#$colnames, name => $_ }
2335 if ($colinfo->{$_}{is_rel} ||= (
2339 ref $data->[$i]{$_} eq 'ARRAY'
2341 ref $data->[$i]{$_} eq 'HASH'
2343 ( defined blessed $data->[$i]{$_} and $data->[$i]{$_}->isa('DBIx::Class::Row') )
2349 # moar sanity check... sigh
2350 for ( ref $data->[$i]{$_} eq 'ARRAY' ? @{$data->[$i]{$_}} : $data->[$i]{$_} ) {
2351 if ( defined blessed $_ and $_->isa('DBIx::Class::Row' ) ) {
2352 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2353 return my $throwaway = $self->populate(@_);
2357 push @$current_slice_seen_rel_infos, $rel_info->{$_};
2361 if ($current_slice_seen_rel_infos) {
2362 push @$slices_with_rels, $data->[$i];
2364 # this is needed further down to decide whether or not to fallback to create()
2365 $colinfo->{$_}{seen_null} ||= ! defined $data->[$i]{$_}
2366 for keys %{$data->[$i]};
2370 $self->throw_exception('Unexpected populate() data structure member type: ' . ref $data->[$i] );
2374 { $_->{attrs}{is_depends_on} }
2375 @{ $current_slice_seen_rel_infos || [] }
2377 carp_unique("Fast-path populate() of belongs_to relationship data is not possible - falling back to regular create()");
2378 return my $throwaway = $self->populate(@_);
2382 if( $slices_with_rels ) {
2384 # need to exclude the rel "columns"
2385 $colnames = [ grep { ! $colinfo->{$_}{is_rel} } @$colnames ];
2387 # extra sanity check - ensure the main source is in fact identifiable
2388 # the localizing of nullability is insane, but oh well... the use-case is legit
2389 my $ci = $rsrc->columns_info($colnames);
2391 $ci->{$_} = { %{$ci->{$_}}, is_nullable => 0 }
2392 for grep { ! $colinfo->{$_}{seen_null} } keys %$ci;
2394 unless( $rsrc->_identifying_column_set($ci) ) {
2395 carp_unique("Fast-path populate() of non-uniquely identifiable rows with related data is not possible - falling back to regular create()");
2396 return my $throwaway = $self->populate(@_);
2400 ### inherit the data locked in the conditions of the resultset
2401 my ($rs_data) = $self->_merge_with_rscond({});
2402 delete @{$rs_data}{@$colnames}; # passed-in stuff takes precedence
2404 # if anything left - decompose rs_data
2406 if (keys %$rs_data) {
2407 push @$rs_data_vals, $rs_data->{$_}
2408 for sort keys %$rs_data;
2413 $guard = $rsrc->schema->storage->txn_scope_guard
2414 if $slices_with_rels;
2416 ### main source data
2417 # FIXME - need to switch entirely to a coderef-based thing,
2418 # so that large sets aren't copied several times... I think
2419 $rsrc->schema->storage->_insert_bulk(
2421 [ @$colnames, sort keys %$rs_data ],
2423 ref $data->[$_] eq 'ARRAY'
2425 $slices_with_rels ? [ @{$data->[$_]}[0..$#$colnames], @{$rs_data_vals||[]} ] # the collist changed
2426 : $rs_data_vals ? [ @{$data->[$_]}, @$rs_data_vals ]
2429 : [ @{$data->[$_]}{@$colnames}, @{$rs_data_vals||[]} ]
2430 } $data_start .. $#$data ],
2433 ### do the children relationships
2434 if ( $slices_with_rels ) {
2435 my @rels = grep { $colinfo->{$_}{is_rel} } keys %$colinfo
2436 or die 'wtf... please report a bug with DBIC_TRACE=1 output (stacktrace)';
2438 for my $sl (@$slices_with_rels) {
2440 my ($main_proto, $main_proto_rs);
2441 for my $rel (@rels) {
2442 next unless defined $sl->{$rel};
2446 (map { $_ => $sl->{$_} } @$colnames),
2449 unless (defined $colinfo->{$rel}{rs}) {
2451 $colinfo->{$rel}{rs} = $rsrc->related_source($rel)->resultset;
2453 $colinfo->{$rel}{fk_map} = { reverse %{ $rsrc->_resolve_relationship_condition(
2455 self_alias => "\xFE", # irrelevant
2456 foreign_alias => "\xFF", # irrelevant
2457 )->{identity_map} || {} } };
2461 $colinfo->{$rel}{rs}->search({ map # only so that we inherit them values properly, no actual search
2464 ( $main_proto_rs ||= $rsrc->resultset->search($main_proto) )
2465 ->get_column( $colinfo->{$rel}{fk_map}{$_} )
2469 keys %{$colinfo->{$rel}{fk_map}}
2470 })->populate( ref $sl->{$rel} eq 'ARRAY' ? $sl->{$rel} : [ $sl->{$rel} ] );
2477 $guard->commit if $guard;
2484 =item Arguments: none
2486 =item Return Value: L<$pager|Data::Page>
2490 Returns a L<Data::Page> object for the current resultset. Only makes
2491 sense for queries with a C<page> attribute.
2493 To get the full count of entries for a paged resultset, call
2494 C<total_entries> on the L<Data::Page> object.
2501 return $self->{pager} if $self->{pager};
2503 my $attrs = $self->{attrs};
2504 if (!defined $attrs->{page}) {
2505 $self->throw_exception("Can't create pager for non-paged rs");
2507 elsif ($attrs->{page} <= 0) {
2508 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2510 $attrs->{rows} ||= 10;
2512 # throw away the paging flags and re-run the count (possibly
2513 # with a subselect) to get the real total count
2514 my $count_attrs = { %$attrs };
2515 delete @{$count_attrs}{qw/rows offset page pager/};
2517 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2519 require DBIx::Class::ResultSet::Pager;
2520 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2521 sub { $total_rs->count }, #lazy-get the total
2523 $self->{attrs}{page},
2531 =item Arguments: $page_number
2533 =item Return Value: L<$resultset|/search>
2537 Returns a resultset for the $page_number page of the resultset on which page
2538 is called, where each page contains a number of rows equal to the 'rows'
2539 attribute set on the resultset (10 by default).
2544 my ($self, $page) = @_;
2545 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2552 =item Arguments: \%col_data
2554 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2558 Creates a new result object in the resultset's result class and returns
2559 it. The row is not inserted into the database at this point, call
2560 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2561 will tell you whether the result object has been inserted or not.
2563 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2568 my ($self, $values) = @_;
2570 $self->throw_exception( "Result object instantiation requires a single hashref argument" )
2571 if @_ > 2 or ref $values ne 'HASH';
2573 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2575 my $new = $self->result_class->new({
2577 ( @$cols_from_relations
2578 ? (-cols_from_relations => $cols_from_relations)
2581 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2585 reftype($new) eq 'HASH'
2591 carp_unique (sprintf (
2592 "%s->new returned a blessed empty hashref - a strong indicator something is wrong with its inheritance chain",
2593 $self->result_class,
2600 # _merge_with_rscond
2602 # Takes a simple hash of K/V data and returns its copy merged with the
2603 # condition already present on the resultset. Additionally returns an
2604 # arrayref of value/condition names, which were inferred from related
2605 # objects (this is needed for in-memory related objects)
2606 sub _merge_with_rscond {
2607 my ($self, $data) = @_;
2609 my ($implied_data, @cols_from_relations);
2611 my $alias = $self->{attrs}{alias};
2613 if (! defined $self->{cond}) {
2614 # just massage $data below
2616 elsif ($self->{cond} eq UNRESOLVABLE_CONDITION) {
2617 $implied_data = $self->{attrs}{related_objects}; # nothing might have been inserted yet
2618 @cols_from_relations = keys %{ $implied_data || {} };
2621 my $eqs = $self->result_source->schema->storage->_extract_fixed_condition_columns($self->{cond}, 'consider_nulls');
2622 $implied_data = { map {
2623 ( ($eqs->{$_}||'') eq UNRESOLVABLE_CONDITION ) ? () : ( $_ => $eqs->{$_} )
2629 { %{ $self->_remove_alias($_, $alias) } }
2630 # precedence must be given to passed values over values inherited from
2631 # the cond, so the order here is important.
2632 ( $implied_data||(), $data)
2634 \@cols_from_relations
2638 # _has_resolved_attr
2640 # determines if the resultset defines at least one
2641 # of the attributes supplied
2643 # used to determine if a subquery is necessary
2645 # supports some virtual attributes:
2647 # This will scan for any joins being present on the resultset.
2648 # It is not a mere key-search but a deep inspection of {from}
2651 sub _has_resolved_attr {
2652 my ($self, @attr_names) = @_;
2654 my $attrs = $self->_resolved_attrs;
2658 for my $n (@attr_names) {
2659 if (grep { $n eq $_ } (qw/-join/) ) {
2660 $extra_checks{$n}++;
2664 my $attr = $attrs->{$n};
2666 next if not defined $attr;
2668 if (ref $attr eq 'HASH') {
2669 return 1 if keys %$attr;
2671 elsif (ref $attr eq 'ARRAY') {
2679 # a resolved join is expressed as a multi-level from
2681 $extra_checks{-join}
2683 ref $attrs->{from} eq 'ARRAY'
2685 @{$attrs->{from}} > 1
2693 # Remove the specified alias from the specified query hash. A copy is made so
2694 # the original query is not modified.
2697 my ($self, $query, $alias) = @_;
2699 my %orig = %{ $query || {} };
2702 foreach my $key (keys %orig) {
2704 $unaliased{$key} = $orig{$key};
2707 $unaliased{$1} = $orig{$key}
2708 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2718 =item Arguments: none
2720 =item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
2724 Returns the SQL query and bind vars associated with the invocant.
2726 This is generally used as the RHS for a subquery.
2733 my $attrs = { %{ $self->_resolved_attrs } };
2735 my $aq = $self->result_source->schema->storage->_select_args_to_query (
2736 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
2746 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2748 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2752 my $artist = $schema->resultset('Artist')->find_or_new(
2753 { artist => 'fred' }, { key => 'artists' });
2755 $cd->cd_to_producer->find_or_new({ producer => $producer },
2756 { key => 'primary' });
2758 Find an existing record from this resultset using L</find>. if none exists,
2759 instantiate a new result object and return it. The object will not be saved
2760 into your storage until you call L<DBIx::Class::Row/insert> on it.
2762 You most likely want this method when looking for existing rows using a unique
2763 constraint that is not the primary key, or looking for related rows.
2765 If you want objects to be saved immediately, use L</find_or_create> instead.
2767 B<Note>: Make sure to read the documentation of L</find> and understand the
2768 significance of the C<key> attribute, as its lack may skew your search, and
2769 subsequently result in spurious new objects.
2771 B<Note>: Take care when using C<find_or_new> with a table having
2772 columns with default values that you intend to be automatically
2773 supplied by the database (e.g. an auto_increment primary key column).
2774 In normal usage, the value of such columns should NOT be included at
2775 all in the call to C<find_or_new>, even when set to C<undef>.
2781 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2782 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2783 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2786 return $self->new_result($hash);
2793 =item Arguments: \%col_data
2795 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2799 Attempt to create a single new row or a row with multiple related rows
2800 in the table represented by the resultset (and related tables). This
2801 will not check for duplicate rows before inserting, use
2802 L</find_or_create> to do that.
2804 To create one row for this resultset, pass a hashref of key/value
2805 pairs representing the columns of the table and the values you wish to
2806 store. If the appropriate relationships are set up, foreign key fields
2807 can also be passed an object representing the foreign row, and the
2808 value will be set to its primary key.
2810 To create related objects, pass a hashref of related-object column values
2811 B<keyed on the relationship name>. If the relationship is of type C<multi>
2812 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2813 The process will correctly identify columns holding foreign keys, and will
2814 transparently populate them from the keys of the corresponding relation.
2815 This can be applied recursively, and will work correctly for a structure
2816 with an arbitrary depth and width, as long as the relationships actually
2817 exists and the correct column data has been supplied.
2819 Instead of hashrefs of plain related data (key/value pairs), you may
2820 also pass new or inserted objects. New objects (not inserted yet, see
2821 L</new_result>), will be inserted into their appropriate tables.
2823 Effectively a shortcut for C<< ->new_result(\%col_data)->insert >>.
2825 Example of creating a new row.
2827 $person_rs->create({
2828 name=>"Some Person",
2829 email=>"somebody@someplace.com"
2832 Example of creating a new row and also creating rows in a related C<has_many>
2833 or C<has_one> resultset. Note Arrayref.
2836 { artistid => 4, name => 'Manufactured Crap', cds => [
2837 { title => 'My First CD', year => 2006 },
2838 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2843 Example of creating a new row and also creating a row in a related
2844 C<belongs_to> resultset. Note Hashref.
2847 title=>"Music for Silly Walks",
2850 name=>"Silly Musician",
2858 When subclassing ResultSet never attempt to override this method. Since
2859 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2860 lot of the internals simply never call it, so your override will be
2861 bypassed more often than not. Override either L<DBIx::Class::Row/new>
2862 or L<DBIx::Class::Row/insert> depending on how early in the
2863 L</create> process you need to intervene. See also warning pertaining to
2871 #my ($self, $col_data) = @_;
2872 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
2873 return shift->new_result(shift)->insert;
2876 =head2 find_or_create
2880 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2882 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2886 $cd->cd_to_producer->find_or_create({ producer => $producer },
2887 { key => 'primary' });
2889 Tries to find a record based on its primary key or unique constraints; if none
2890 is found, creates one and returns that instead.
2892 my $cd = $schema->resultset('CD')->find_or_create({
2894 artist => 'Massive Attack',
2895 title => 'Mezzanine',
2899 Also takes an optional C<key> attribute, to search by a specific key or unique
2900 constraint. For example:
2902 my $cd = $schema->resultset('CD')->find_or_create(
2904 artist => 'Massive Attack',
2905 title => 'Mezzanine',
2907 { key => 'cd_artist_title' }
2910 B<Note>: Make sure to read the documentation of L</find> and understand the
2911 significance of the C<key> attribute, as its lack may skew your search, and
2912 subsequently result in spurious row creation.
2914 B<Note>: Because find_or_create() reads from the database and then
2915 possibly inserts based on the result, this method is subject to a race
2916 condition. Another process could create a record in the table after
2917 the find has completed and before the create has started. To avoid
2918 this problem, use find_or_create() inside a transaction.
2920 B<Note>: Take care when using C<find_or_create> with a table having
2921 columns with default values that you intend to be automatically
2922 supplied by the database (e.g. an auto_increment primary key column).
2923 In normal usage, the value of such columns should NOT be included at
2924 all in the call to C<find_or_create>, even when set to C<undef>.
2926 See also L</find> and L</update_or_create>. For information on how to declare
2927 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2929 If you need to know if an existing row was found or a new one created use
2930 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2931 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2934 my $cd = $schema->resultset('CD')->find_or_new({
2936 artist => 'Massive Attack',
2937 title => 'Mezzanine',
2941 if( !$cd->in_storage ) {
2948 sub find_or_create {
2950 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2951 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2952 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2955 return $self->new_result($hash)->insert;
2958 =head2 update_or_create
2962 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2964 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2968 $resultset->update_or_create({ col => $val, ... });
2970 Like L</find_or_create>, but if a row is found it is immediately updated via
2971 C<< $found_row->update (\%col_data) >>.
2974 Takes an optional C<key> attribute to search on a specific unique constraint.
2977 # In your application
2978 my $cd = $schema->resultset('CD')->update_or_create(
2980 artist => 'Massive Attack',
2981 title => 'Mezzanine',
2984 { key => 'cd_artist_title' }
2987 $cd->cd_to_producer->update_or_create({
2988 producer => $producer,
2994 B<Note>: Make sure to read the documentation of L</find> and understand the
2995 significance of the C<key> attribute, as its lack may skew your search, and
2996 subsequently result in spurious row creation.
2998 B<Note>: Take care when using C<update_or_create> with a table having
2999 columns with default values that you intend to be automatically
3000 supplied by the database (e.g. an auto_increment primary key column).
3001 In normal usage, the value of such columns should NOT be included at
3002 all in the call to C<update_or_create>, even when set to C<undef>.
3004 See also L</find> and L</find_or_create>. For information on how to declare
3005 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
3007 If you need to know if an existing row was updated or a new one created use
3008 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
3009 to call L<DBIx::Class::Row/insert> to save the newly created row to the
3014 sub update_or_create {
3016 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
3017 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3019 my $row = $self->find($cond, $attrs);
3021 $row->update($cond);
3025 return $self->new_result($cond)->insert;
3028 =head2 update_or_new
3032 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
3034 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
3038 $resultset->update_or_new({ col => $val, ... });
3040 Like L</find_or_new> but if a row is found it is immediately updated via
3041 C<< $found_row->update (\%col_data) >>.
3045 # In your application
3046 my $cd = $schema->resultset('CD')->update_or_new(
3048 artist => 'Massive Attack',
3049 title => 'Mezzanine',
3052 { key => 'cd_artist_title' }
3055 if ($cd->in_storage) {
3056 # the cd was updated
3059 # the cd is not yet in the database, let's insert it
3063 B<Note>: Make sure to read the documentation of L</find> and understand the
3064 significance of the C<key> attribute, as its lack may skew your search, and
3065 subsequently result in spurious new objects.
3067 B<Note>: Take care when using C<update_or_new> with a table having
3068 columns with default values that you intend to be automatically
3069 supplied by the database (e.g. an auto_increment primary key column).
3070 In normal usage, the value of such columns should NOT be included at
3071 all in the call to C<update_or_new>, even when set to C<undef>.
3073 See also L</find>, L</find_or_create> and L</find_or_new>.
3079 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
3080 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3082 my $row = $self->find( $cond, $attrs );
3083 if ( defined $row ) {
3084 $row->update($cond);
3088 return $self->new_result($cond);
3095 =item Arguments: none
3097 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass> | undef
3101 Gets the contents of the cache for the resultset, if the cache is set.
3103 The cache is populated either by using the L</prefetch> attribute to
3104 L</search> or by calling L</set_cache>.
3116 =item Arguments: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3118 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3122 Sets the contents of the cache for the resultset. Expects an arrayref
3123 of objects of the same class as those produced by the resultset. Note that
3124 if the cache is set, the resultset will return the cached objects rather
3125 than re-querying the database even if the cache attr is not set.
3127 The contents of the cache can also be populated by using the
3128 L</prefetch> attribute to L</search>.
3133 my ( $self, $data ) = @_;
3134 $self->throw_exception("set_cache requires an arrayref")
3135 if defined($data) && (ref $data ne 'ARRAY');
3136 $self->{all_cache} = $data;
3143 =item Arguments: none
3145 =item Return Value: undef
3149 Clears the cache for the resultset.
3154 shift->set_cache(undef);
3161 =item Arguments: none
3163 =item Return Value: true, if the resultset has been paginated
3171 return !!$self->{attrs}{page};
3178 =item Arguments: none
3180 =item Return Value: true, if the resultset has been ordered with C<order_by>.
3188 return scalar $self->result_source->schema->storage->_extract_order_criteria($self->{attrs}{order_by});
3191 =head2 related_resultset
3195 =item Arguments: $rel_name
3197 =item Return Value: L<$resultset|/search>
3201 Returns a related resultset for the supplied relationship name.
3203 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
3207 sub related_resultset {
3208 $_[0]->throw_exception(
3209 'Extra arguments to $rs->related_resultset() were always quietly '
3210 . 'discarded without consideration, you need to switch to '
3211 . '...->related_resultset( $relname )->search_rs( $search, $args ) instead.'
3214 return $_[0]->{related_resultsets}{$_[1]}
3215 if defined $_[0]->{related_resultsets}{$_[1]};
3217 my ($self, $rel) = @_;
3219 return $self->{related_resultsets}{$rel} = do {
3220 my $rsrc = $self->result_source;
3221 my $rel_info = $rsrc->relationship_info($rel);
3223 $self->throw_exception(
3224 "search_related: result source '" . $rsrc->source_name .
3225 "' has no such relationship $rel")
3228 my $attrs = $self->_chain_relationship($rel);
3230 my $storage = $rsrc->schema->storage;
3232 # Previously this atribute was deleted (instead of being set as it is now)
3233 # Doing so seems to be harmless in all available test permutations
3234 # See also 01d59a6a6 and mst's comment below
3236 $attrs->{alias} = $storage->relname_to_table_alias(
3238 $attrs->{seen_join}{$rel}
3241 # since this is search_related, and we already slid the select window inwards
3242 # (the select/as attrs were deleted in the beginning), we need to flip all
3243 # left joins to inner, so we get the expected results
3244 # read the comment on top of the actual function to see what this does
3245 $attrs->{from} = $storage->_inner_join_to_node( $attrs->{from}, $attrs->{alias} );
3247 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3248 delete $attrs->{result_class};
3252 # The reason we do this now instead of passing the alias to the
3253 # search_rs below is that if you wrap/overload resultset on the
3254 # source you need to know what alias it's -going- to have for things
3255 # to work sanely (e.g. RestrictWithObject wants to be able to add
3256 # extra query restrictions, and these may need to be $alias.)
3257 # -- mst ~ 2007 (01d59a6a6)
3259 # FIXME - this seems to be no longer neccessary (perhaps due to the
3260 # advances in relcond resolution. Testing DBIC::S::RWO and its only
3261 # dependent (as of Jun 2015 ) does not yield any difference with or
3262 # without this line. Nevertheless keep it as is for now, to minimize
3263 # churn, there is enough potential for breakage in 0.0829xx as it is
3264 # -- ribasushi Jun 2015
3266 my $rel_source = $rsrc->related_source($rel);
3267 local $rel_source->resultset_attributes->{alias} = $attrs->{alias};
3269 $rel_source->resultset->search_rs( undef, $attrs );
3272 if (my $cache = $self->get_cache) {
3273 my @related_cache = map
3274 { $_->related_resultset($rel)->get_cache || () }
3278 $new->set_cache([ map @$_, @related_cache ]) if @related_cache == @$cache;
3285 =head2 current_source_alias
3289 =item Arguments: none
3291 =item Return Value: $source_alias
3295 Returns the current table alias for the result source this resultset is built
3296 on, that will be used in the SQL query. Usually it is C<me>.
3298 Currently the source alias that refers to the result set returned by a
3299 L</search>/L</find> family method depends on how you got to the resultset: it's
3300 C<me> by default, but eg. L</search_related> aliases it to the related result
3301 source name (and keeps C<me> referring to the original result set). The long
3302 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3303 (and make this method unnecessary).
3305 Thus it's currently necessary to use this method in predefined queries (see
3306 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3307 source alias of the current result set:
3309 # in a result set class
3311 my ($self, $user) = @_;
3313 my $me = $self->current_source_alias;
3315 return $self->search({
3316 "$me.modified" => $user->id,
3320 The alias of L<newly created resultsets|/search> can be altered by the
3321 L<alias attribute|/alias>.
3325 sub current_source_alias {
3326 return (shift->{attrs} || {})->{alias} || 'me';
3329 =head2 as_subselect_rs
3333 =item Arguments: none
3335 =item Return Value: L<$resultset|/search>
3339 Act as a barrier to SQL symbols. The resultset provided will be made into a
3340 "virtual view" by including it as a subquery within the from clause. From this
3341 point on, any joined tables are inaccessible to ->search on the resultset (as if
3342 it were simply where-filtered without joins). For example:
3344 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3346 # 'x' now pollutes the query namespace
3348 # So the following works as expected
3349 my $ok_rs = $rs->search({'x.other' => 1});
3351 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3352 # def) we look for one row with contradictory terms and join in another table
3353 # (aliased 'x_2') which we never use
3354 my $broken_rs = $rs->search({'x.name' => 'def'});
3356 my $rs2 = $rs->as_subselect_rs;
3358 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3359 my $not_joined_rs = $rs2->search({'x.other' => 1});
3361 # works as expected: finds a 'table' row related to two x rows (abc and def)
3362 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3364 Another example of when one might use this would be to select a subset of
3365 columns in a group by clause:
3367 my $rs = $schema->resultset('Bar')->search(undef, {
3368 group_by => [qw{ id foo_id baz_id }],
3369 })->as_subselect_rs->search(undef, {
3370 columns => [qw{ id foo_id }]
3373 In the above example normally columns would have to be equal to the group by,
3374 but because we isolated the group by into a subselect the above works.
3378 sub as_subselect_rs {
3381 my $attrs = $self->_resolved_attrs;
3383 my $fresh_rs = (ref $self)->new (
3384 $self->result_source
3387 # these pieces will be locked in the subquery
3388 delete $fresh_rs->{cond};
3389 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3391 return $fresh_rs->search( {}, {
3393 $attrs->{alias} => $self->as_query,
3394 -alias => $attrs->{alias},
3395 -rsrc => $self->result_source,
3397 alias => $attrs->{alias},
3401 # This code is called by search_related, and makes sure there
3402 # is clear separation between the joins before, during, and
3403 # after the relationship. This information is needed later
3404 # in order to properly resolve prefetch aliases (any alias
3405 # with a relation_chain_depth less than the depth of the
3406 # current prefetch is not considered)
3408 # The increments happen twice per join. An even number means a
3409 # relationship specified via a search_related, whereas an odd
3410 # number indicates a join/prefetch added via attributes
3412 # Also this code will wrap the current resultset (the one we
3413 # chain to) in a subselect IFF it contains limiting attributes
3414 sub _chain_relationship {
3415 my ($self, $rel) = @_;
3416 my $source = $self->result_source;
3417 my $attrs = { %{$self->{attrs}||{}} };
3419 # we need to take the prefetch the attrs into account before we
3420 # ->_resolve_join as otherwise they get lost - captainL
3421 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3423 delete @{$attrs}{qw/join prefetch collapse group_by distinct _grouped_by_distinct select as columns +select +as +columns/};
3425 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3428 my @force_subq_attrs = qw/offset rows group_by having/;
3431 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3433 $self->_has_resolved_attr (@force_subq_attrs)
3435 # Nuke the prefetch (if any) before the new $rs attrs
3436 # are resolved (prefetch is useless - we are wrapping
3437 # a subquery anyway).
3438 my $rs_copy = $self->search;
3439 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3440 $rs_copy->{attrs}{join},
3441 delete $rs_copy->{attrs}{prefetch},
3446 -alias => $attrs->{alias},
3447 $attrs->{alias} => $rs_copy->as_query,
3449 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3450 $seen->{-relation_chain_depth} = 0;
3452 elsif ($attrs->{from}) { #shallow copy suffices
3453 $from = [ @{$attrs->{from}} ];
3458 -alias => $attrs->{alias},
3459 $attrs->{alias} => $source->from,
3463 my $jpath = ($seen->{-relation_chain_depth})
3464 ? $from->[-1][0]{-join_path}
3467 my @requested_joins = $source->_resolve_join(
3474 push @$from, @requested_joins;
3476 $seen->{-relation_chain_depth}++;
3478 # if $self already had a join/prefetch specified on it, the requested
3479 # $rel might very well be already included. What we do in this case
3480 # is effectively a no-op (except that we bump up the chain_depth on
3481 # the join in question so we could tell it *is* the search_related)
3484 # we consider the last one thus reverse
3485 for my $j (reverse @requested_joins) {
3486 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3487 if ($rel eq $last_j) {
3488 $j->[0]{-relation_chain_depth}++;
3494 unless ($already_joined) {
3495 push @$from, $source->_resolve_join(
3503 $seen->{-relation_chain_depth}++;
3505 return {%$attrs, from => $from, seen_join => $seen};
3508 sub _resolved_attrs {
3510 return $self->{_attrs} if $self->{_attrs};
3512 my $attrs = { %{ $self->{attrs} || {} } };
3513 my $source = $attrs->{result_source} = $self->result_source;
3514 my $alias = $attrs->{alias};
3516 $self->throw_exception("Specifying distinct => 1 in conjunction with collapse => 1 is unsupported")
3517 if $attrs->{collapse} and $attrs->{distinct};
3520 # Sanity check the paging attributes
3521 # SQLMaker does it too, but in case of a software_limit we'll never get there
3522 if (defined $attrs->{offset}) {
3523 $self->throw_exception('A supplied offset attribute must be a non-negative integer')
3524 if ( $attrs->{offset} =~ /[^0-9]/ or $attrs->{offset} < 0 );
3526 if (defined $attrs->{rows}) {
3527 $self->throw_exception("The rows attribute must be a positive integer if present")
3528 if ( $attrs->{rows} =~ /[^0-9]/ or $attrs->{rows} <= 0 );
3532 # default selection list
3533 $attrs->{columns} = [ $source->columns ]
3534 unless grep { exists $attrs->{$_} } qw/columns cols select as/;
3536 # merge selectors together
3537 for (qw/columns select as/) {
3538 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3539 if $attrs->{$_} or $attrs->{"+$_"};
3542 # disassemble columns
3544 if (my $cols = delete $attrs->{columns}) {
3545 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3546 if (ref $c eq 'HASH') {
3547 for my $as (sort keys %$c) {
3548 push @sel, $c->{$as};
3559 # when trying to weed off duplicates later do not go past this point -
3560 # everything added from here on is unbalanced "anyone's guess" stuff
3561 my $dedup_stop_idx = $#as;
3563 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3565 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3566 if $attrs->{select};
3568 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3569 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3571 # disqualify all $alias.col as-bits (inflate-map mandated)
3572 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3574 # de-duplicate the result (remove *identical* select/as pairs)
3575 # and also die on duplicate {as} pointing to different {select}s
3576 # not using a c-style for as the condition is prone to shrinkage
3579 while ($i <= $dedup_stop_idx) {
3580 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3585 elsif ($seen->{$as[$i]}++) {
3586 $self->throw_exception(
3587 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3595 $attrs->{select} = \@sel;
3596 $attrs->{as} = \@as;
3598 $attrs->{from} ||= [{
3600 -alias => $self->{attrs}{alias},
3601 $self->{attrs}{alias} => $source->from,
3604 if ( $attrs->{join} || $attrs->{prefetch} ) {
3606 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3607 if ref $attrs->{from} ne 'ARRAY';
3609 my $join = (delete $attrs->{join}) || {};
3611 if ( defined $attrs->{prefetch} ) {
3612 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3615 $attrs->{from} = # have to copy here to avoid corrupting the original
3617 @{ $attrs->{from} },
3618 $source->_resolve_join(
3621 { %{ $attrs->{seen_join} || {} } },
3622 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3623 ? $attrs->{from}[-1][0]{-join_path}
3631 for my $attr (qw(order_by group_by)) {
3633 if ( defined $attrs->{$attr} ) {
3635 ref( $attrs->{$attr} ) eq 'ARRAY'
3636 ? [ @{ $attrs->{$attr} } ]
3637 : [ $attrs->{$attr} || () ]
3640 delete $attrs->{$attr} unless @{$attrs->{$attr}};
3645 # set collapse default based on presence of prefetch
3648 defined $attrs->{prefetch}
3650 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3652 $self->throw_exception("Specifying prefetch in conjunction with an explicit collapse => 0 is unsupported")
3653 if defined $attrs->{collapse} and ! $attrs->{collapse};
3655 $attrs->{collapse} = 1;
3659 # run through the resulting joinstructure (starting from our current slot)
3660 # and unset collapse if proven unnecessary
3662 # also while we are at it find out if the current root source has
3663 # been premultiplied by previous related_source chaining
3665 # this allows to predict whether a root object with all other relation
3666 # data set to NULL is in fact unique
3667 if ($attrs->{collapse}) {
3669 if (ref $attrs->{from} eq 'ARRAY') {
3671 if (@{$attrs->{from}} == 1) {
3672 # no joins - no collapse
3673 $attrs->{collapse} = 0;
3676 # find where our table-spec starts
3677 my @fromlist = @{$attrs->{from}};
3679 my $t = shift @fromlist;
3682 # me vs join from-spec distinction - a ref means non-root
3683 if (ref $t eq 'ARRAY') {
3685 $is_multi ||= ! $t->{-is_single};
3687 last if ($t->{-alias} && $t->{-alias} eq $alias);
3688 $attrs->{_main_source_premultiplied} ||= $is_multi;
3691 # no non-singles remaining, nor any premultiplication - nothing to collapse
3693 ! $attrs->{_main_source_premultiplied}
3695 ! grep { ! $_->[0]{-is_single} } @fromlist
3697 $attrs->{collapse} = 0;
3703 # if we can not analyze the from - err on the side of safety
3704 $attrs->{_main_source_premultiplied} = 1;
3709 # generate the distinct induced group_by before injecting the prefetched select/as parts
3710 if (delete $attrs->{distinct}) {
3711 if ($attrs->{group_by}) {
3712 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3715 $attrs->{_grouped_by_distinct} = 1;
3716 # distinct affects only the main selection part, not what prefetch may add below
3717 ($attrs->{group_by}, my $new_order) = $source->schema->storage->_group_over_selection($attrs);
3719 # FIXME possibly ignore a rewritten order_by (may turn out to be an issue)
3720 # The thinking is: if we are collapsing the subquerying prefetch engine will
3721 # rip stuff apart for us anyway, and we do not want to have a potentially
3722 # function-converted external order_by
3723 # ( there is an explicit if ( collapse && _grouped_by_distinct ) check in DBIHacks )
3724 $attrs->{order_by} = $new_order unless $attrs->{collapse};
3729 # generate selections based on the prefetch helper
3732 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3733 if $attrs->{_dark_selector};
3735 # this is a separate structure (we don't look in {from} directly)
3736 # as the resolver needs to shift things off the lists to work
3737 # properly (identical-prefetches on different branches)
3738 my $joined_node_aliases_map = {};
3739 if (ref $attrs->{from} eq 'ARRAY') {
3741 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3743 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3744 next unless $j->[0]{-alias};
3745 next unless $j->[0]{-join_path};
3746 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3748 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3750 my $p = $joined_node_aliases_map;
3751 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3752 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3756 ( push @{$attrs->{select}}, $_->[0] ) and ( push @{$attrs->{as}}, $_->[1] )
3757 for $source->_resolve_selection_from_prefetch( $prefetch, $joined_node_aliases_map );
3761 $attrs->{_simple_passthrough_construction} = !(
3764 grep { $_ =~ /\./ } @{$attrs->{as}}
3768 # if both page and offset are specified, produce a combined offset
3769 # even though it doesn't make much sense, this is what pre 081xx has
3771 if (my $page = delete $attrs->{page}) {
3773 ($attrs->{rows} * ($page - 1))
3775 ($attrs->{offset} || 0)
3779 return $self->{_attrs} = $attrs;
3783 my ($self, $attr) = @_;
3785 if (ref $attr eq 'HASH') {
3786 return $self->_rollout_hash($attr);
3787 } elsif (ref $attr eq 'ARRAY') {
3788 return $self->_rollout_array($attr);
3794 sub _rollout_array {
3795 my ($self, $attr) = @_;
3798 foreach my $element (@{$attr}) {
3799 if (ref $element eq 'HASH') {
3800 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3801 } elsif (ref $element eq 'ARRAY') {
3802 # XXX - should probably recurse here
3803 push( @rolled_array, @{$self->_rollout_array($element)} );
3805 push( @rolled_array, $element );
3808 return \@rolled_array;
3812 my ($self, $attr) = @_;
3815 foreach my $key (keys %{$attr}) {
3816 push( @rolled_array, { $key => $attr->{$key} } );
3818 return \@rolled_array;
3821 sub _calculate_score {
3822 my ($self, $a, $b) = @_;
3824 if (defined $a xor defined $b) {
3827 elsif (not defined $a) {
3831 if (ref $b eq 'HASH') {
3832 my ($b_key) = keys %{$b};
3833 $b_key = '' if ! defined $b_key;
3834 if (ref $a eq 'HASH') {
3835 my ($a_key) = keys %{$a};
3836 $a_key = '' if ! defined $a_key;
3837 if ($a_key eq $b_key) {
3838 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3843 return ($a eq $b_key) ? 1 : 0;
3846 if (ref $a eq 'HASH') {
3847 my ($a_key) = keys %{$a};
3848 return ($b eq $a_key) ? 1 : 0;
3850 return ($b eq $a) ? 1 : 0;
3855 sub _merge_joinpref_attr {
3856 my ($self, $orig, $import) = @_;
3858 return $import unless defined($orig);
3859 return $orig unless defined($import);
3861 $orig = $self->_rollout_attr($orig);
3862 $import = $self->_rollout_attr($import);
3865 foreach my $import_element ( @{$import} ) {
3866 # find best candidate from $orig to merge $b_element into
3867 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3868 foreach my $orig_element ( @{$orig} ) {
3869 my $score = $self->_calculate_score( $orig_element, $import_element );
3870 if ($score > $best_candidate->{score}) {
3871 $best_candidate->{position} = $position;
3872 $best_candidate->{score} = $score;
3876 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3877 $import_key = '' if not defined $import_key;
3879 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3880 push( @{$orig}, $import_element );
3882 my $orig_best = $orig->[$best_candidate->{position}];
3883 # merge orig_best and b_element together and replace original with merged
3884 if (ref $orig_best ne 'HASH') {
3885 $orig->[$best_candidate->{position}] = $import_element;
3886 } elsif (ref $import_element eq 'HASH') {
3887 my ($key) = keys %{$orig_best};
3888 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3891 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3894 return @$orig ? $orig : ();
3902 require Hash::Merge;
3903 my $hm = Hash::Merge->new;
3905 $hm->specify_behavior({
3908 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3910 if ($defl xor $defr) {
3911 return [ $defl ? $_[0] : $_[1] ];
3916 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3920 return [$_[0], $_[1]];
3924 return $_[1] if !defined $_[0];
3925 return $_[1] if __HM_DEDUP and grep { $_ eq $_[0] } @{$_[1]};
3926 return [$_[0], @{$_[1]}]
3929 return [] if !defined $_[0] and !keys %{$_[1]};
3930 return [ $_[1] ] if !defined $_[0];
3931 return [ $_[0] ] if !keys %{$_[1]};
3932 return [$_[0], $_[1]]
3937 return $_[0] if !defined $_[1];
3938 return $_[0] if __HM_DEDUP and grep { $_ eq $_[1] } @{$_[0]};
3939 return [@{$_[0]}, $_[1]]
3942 my @ret = @{$_[0]} or return $_[1];
3943 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3944 my %idx = map { $_ => 1 } @ret;
3945 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3949 return [ $_[1] ] if ! @{$_[0]};
3950 return $_[0] if !keys %{$_[1]};
3951 return $_[0] if __HM_DEDUP and grep { $_ eq $_[1] } @{$_[0]};
3952 return [ @{$_[0]}, $_[1] ];
3957 return [] if !keys %{$_[0]} and !defined $_[1];
3958 return [ $_[0] ] if !defined $_[1];
3959 return [ $_[1] ] if !keys %{$_[0]};
3960 return [$_[0], $_[1]]
3963 return [] if !keys %{$_[0]} and !@{$_[1]};
3964 return [ $_[0] ] if !@{$_[1]};
3965 return $_[1] if !keys %{$_[0]};
3966 return $_[1] if __HM_DEDUP and grep { $_ eq $_[0] } @{$_[1]};
3967 return [ $_[0], @{$_[1]} ];
3970 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3971 return [ $_[0] ] if !keys %{$_[1]};
3972 return [ $_[1] ] if !keys %{$_[0]};
3973 return [ $_[0] ] if $_[0] eq $_[1];
3974 return [ $_[0], $_[1] ];
3977 } => 'DBIC_RS_ATTR_MERGER');
3981 return $hm->merge ($_[1], $_[2]);
3985 sub STORABLE_freeze {
3986 my ($self, $cloning) = @_;
3987 my $to_serialize = { %$self };
3989 # A cursor in progress can't be serialized (and would make little sense anyway)
3990 # the parser can be regenerated (and can't be serialized)
3991 delete @{$to_serialize}{qw/cursor _row_parser _result_inflator/};
3993 # nor is it sensical to store a not-yet-fired-count pager
3994 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3995 delete $to_serialize->{pager};
3998 Storable::nfreeze($to_serialize);
4001 # need this hook for symmetry
4003 my ($self, $cloning, $serialized) = @_;
4005 %$self = %{ Storable::thaw($serialized) };
4011 =head2 throw_exception
4013 See L<DBIx::Class::Schema/throw_exception> for details.
4017 sub throw_exception {
4020 if (ref $self and my $rsrc = $self->result_source) {
4021 $rsrc->throw_exception(@_)
4024 DBIx::Class::Exception->throw(@_);
4032 # XXX: FIXME: Attributes docs need clearing up
4036 Attributes are used to refine a ResultSet in various ways when
4037 searching for data. They can be passed to any method which takes an
4038 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
4041 Default attributes can be set on the result class using
4042 L<DBIx::Class::ResultSource/resultset_attributes>. (Please read
4043 the CAVEATS on that feature before using it!)
4045 These are in no particular order:
4051 =item Value: ( $order_by | \@order_by | \%order_by )
4055 Which column(s) to order the results by.
4057 [The full list of suitable values is documented in
4058 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
4061 If a single column name, or an arrayref of names is supplied, the
4062 argument is passed through directly to SQL. The hashref syntax allows
4063 for connection-agnostic specification of ordering direction:
4065 For descending order:
4067 order_by => { -desc => [qw/col1 col2 col3/] }
4069 For explicit ascending order:
4071 order_by => { -asc => 'col' }
4073 The old scalarref syntax (i.e. order_by => \'year DESC') is still
4074 supported, although you are strongly encouraged to use the hashref
4075 syntax as outlined above.
4081 =item Value: \@columns | \%columns | $column
4085 Shortcut to request a particular set of columns to be retrieved. Each
4086 column spec may be a string (a table column name), or a hash (in which
4087 case the key is the C<as> value, and the value is used as the C<select>
4088 expression). Adds the L</current_source_alias> onto the start of any column without a C<.> in
4089 it and sets C<select> from that, then auto-populates C<as> from
4090 C<select> as normal. (You may also use the C<cols> attribute, as in
4091 earlier versions of DBIC, but this is deprecated)
4093 Essentially C<columns> does the same as L</select> and L</as>.
4095 columns => [ 'some_column', { dbic_slot => 'another_column' } ]
4099 select => [qw(some_column another_column)],
4100 as => [qw(some_column dbic_slot)]
4102 If you want to individually retrieve related columns (in essence perform
4103 manual L</prefetch>) you have to make sure to specify the correct inflation slot
4104 chain such that it matches existing relationships:
4106 my $rs = $schema->resultset('Artist')->search({}, {
4107 # required to tell DBIC to collapse has_many relationships
4109 join => { cds => 'tracks' },
4111 'cds.cdid' => 'cds.cdid',
4112 'cds.tracks.title' => 'tracks.title',
4116 Like elsewhere, literal SQL or literal values can be included by using a
4117 scalar reference or a literal bind value, and these values will be available
4118 in the result with C<get_column> (see also
4119 L<SQL::Abstract/Literal SQL and value type operators>):
4121 # equivalent SQL: SELECT 1, 'a string', IF(my_column,?,?) ...
4122 # bind values: $true_value, $false_value
4126 bar => \q{'a string'},
4127 baz => \[ 'IF(my_column,?,?)', $true_value, $false_value ],
4133 B<NOTE:> You B<MUST> explicitly quote C<'+columns'> when using this attribute.
4134 Not doing so causes Perl to incorrectly interpret C<+columns> as a bareword
4135 with a unary plus operator before it, which is the same as simply C<columns>.
4139 =item Value: \@extra_columns
4143 Indicates additional columns to be selected from storage. Works the same as
4144 L</columns> but adds columns to the current selection. (You may also use the
4145 C<include_columns> attribute, as in earlier versions of DBIC, but this is
4148 $schema->resultset('CD')->search(undef, {
4149 '+columns' => ['artist.name'],
4153 would return all CDs and include a 'name' column to the information
4154 passed to object inflation. Note that the 'artist' is the name of the
4155 column (or relationship) accessor, and 'name' is the name of the column
4156 accessor in the related table.
4162 =item Value: \@select_columns
4166 Indicates which columns should be selected from the storage. You can use
4167 column names, or in the case of RDBMS back ends, function or stored procedure
4170 $rs = $schema->resultset('Employee')->search(undef, {
4173 { count => 'employeeid' },
4174 { max => { length => 'name' }, -as => 'longest_name' }
4179 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
4181 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
4182 use L</select>, to instruct DBIx::Class how to store the result of the column.
4184 Also note that the L</as> attribute has B<nothing to do> with the SQL-side
4185 C<AS> identifier aliasing. You B<can> alias a function (so you can use it e.g.
4186 in an C<ORDER BY> clause), however this is done via the C<-as> B<select
4187 function attribute> supplied as shown in the example above.
4191 B<NOTE:> You B<MUST> explicitly quote C<'+select'> when using this attribute.
4192 Not doing so causes Perl to incorrectly interpret C<+select> as a bareword
4193 with a unary plus operator before it, which is the same as simply C<select>.
4197 =item Value: \@extra_select_columns
4201 Indicates additional columns to be selected from storage. Works the same as
4202 L</select> but adds columns to the current selection, instead of specifying
4203 a new explicit list.
4209 =item Value: \@inflation_names
4213 Indicates DBIC-side names for object inflation. That is L</as> indicates the
4214 slot name in which the column value will be stored within the
4215 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
4216 identifier by the C<get_column> method (or via the object accessor B<if one
4217 with the same name already exists>) as shown below.
4219 The L</as> attribute has B<nothing to do> with the SQL-side identifier
4220 aliasing C<AS>. See L</select> for details.
4222 $rs = $schema->resultset('Employee')->search(undef, {
4225 { count => 'employeeid' },
4226 { max => { length => 'name' }, -as => 'longest_name' }
4235 If the object against which the search is performed already has an accessor
4236 matching a column name specified in C<as>, the value can be retrieved using
4237 the accessor as normal:
4239 my $name = $employee->name();
4241 If on the other hand an accessor does not exist in the object, you need to
4242 use C<get_column> instead:
4244 my $employee_count = $employee->get_column('employee_count');
4246 You can create your own accessors if required - see
4247 L<DBIx::Class::Manual::Cookbook> for details.
4251 B<NOTE:> You B<MUST> explicitly quote C<'+as'> when using this attribute.
4252 Not doing so causes Perl to incorrectly interpret C<+as> as a bareword
4253 with a unary plus operator before it, which is the same as simply C<as>.
4257 =item Value: \@extra_inflation_names
4261 Indicates additional inflation names for selectors added via L</+select>. See L</as>.
4267 =item Value: ($rel_name | \@rel_names | \%rel_names)
4271 Contains a list of relationships that should be joined for this query. For
4274 # Get CDs by Nine Inch Nails
4275 my $rs = $schema->resultset('CD')->search(
4276 { 'artist.name' => 'Nine Inch Nails' },
4277 { join => 'artist' }
4280 Can also contain a hash reference to refer to the other relation's relations.
4283 package MyApp::Schema::Track;
4284 use base qw/DBIx::Class/;
4285 __PACKAGE__->table('track');
4286 __PACKAGE__->add_columns(qw/trackid cd position title/);
4287 __PACKAGE__->set_primary_key('trackid');
4288 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
4291 # In your application
4292 my $rs = $schema->resultset('Artist')->search(
4293 { 'track.title' => 'Teardrop' },
4295 join => { cd => 'track' },
4296 order_by => 'artist.name',
4300 You need to use the relationship (not the table) name in conditions,
4301 because they are aliased as such. The current table is aliased as "me", so
4302 you need to use me.column_name in order to avoid ambiguity. For example:
4304 # Get CDs from 1984 with a 'Foo' track
4305 my $rs = $schema->resultset('CD')->search(
4308 'tracks.name' => 'Foo'
4310 { join => 'tracks' }
4313 If the same join is supplied twice, it will be aliased to <rel>_2 (and
4314 similarly for a third time). For e.g.
4316 my $rs = $schema->resultset('Artist')->search({
4317 'cds.title' => 'Down to Earth',
4318 'cds_2.title' => 'Popular',
4320 join => [ qw/cds cds/ ],
4323 will return a set of all artists that have both a cd with title 'Down
4324 to Earth' and a cd with title 'Popular'.
4326 If you want to fetch related objects from other tables as well, see L</prefetch>
4329 NOTE: An internal join-chain pruner will discard certain joins while
4330 constructing the actual SQL query, as long as the joins in question do not
4331 affect the retrieved result. This for example includes 1:1 left joins
4332 that are not part of the restriction specification (WHERE/HAVING) nor are
4333 a part of the query selection.
4335 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4341 =item Value: (0 | 1)
4345 When set to a true value, indicates that any rows fetched from joined has_many
4346 relationships are to be aggregated into the corresponding "parent" object. For
4347 example, the resultset:
4349 my $rs = $schema->resultset('CD')->search({}, {
4350 '+columns' => [ qw/ tracks.title tracks.position / ],
4355 While executing the following query:
4357 SELECT me.*, tracks.title, tracks.position
4359 LEFT JOIN track tracks
4360 ON tracks.cdid = me.cdid
4362 Will return only as many objects as there are rows in the CD source, even
4363 though the result of the query may span many rows. Each of these CD objects
4364 will in turn have multiple "Track" objects hidden behind the has_many
4365 generated accessor C<tracks>. Without C<< collapse => 1 >>, the return values
4366 of this resultset would be as many CD objects as there are tracks (a "Cartesian
4367 product"), with each CD object containing exactly one of all fetched Track data.
4369 When a collapse is requested on a non-ordered resultset, an order by some
4370 unique part of the main source (the left-most table) is inserted automatically.
4371 This is done so that the resultset is allowed to be "lazy" - calling
4372 L<< $rs->next|/next >> will fetch only as many rows as it needs to build the next
4373 object with all of its related data.
4375 If an L</order_by> is already declared, and orders the resultset in a way that
4376 makes collapsing as described above impossible (e.g. C<< ORDER BY
4377 has_many_rel.column >> or C<ORDER BY RANDOM()>), DBIC will automatically
4378 switch to "eager" mode and slurp the entire resultset before constructing the
4379 first object returned by L</next>.
4381 Setting this attribute on a resultset that does not join any has_many
4382 relations is a no-op.
4384 For a more in-depth discussion, see L</PREFETCHING>.
4390 =item Value: ($rel_name | \@rel_names | \%rel_names)
4394 This attribute is a shorthand for specifying a L</join> spec, adding all
4395 columns from the joined related sources as L</+columns> and setting
4396 L</collapse> to a true value. It can be thought of as a rough B<superset>
4397 of the L</join> attribute.
4399 For example, the following two queries are equivalent:
4401 my $rs = $schema->resultset('Artist')->search({}, {
4402 prefetch => { cds => ['genre', 'tracks' ] },
4407 my $rs = $schema->resultset('Artist')->search({}, {
4408 join => { cds => ['genre', 'tracks' ] },
4412 { +{ "cds.$_" => "cds.$_" } }
4413 $schema->source('Artist')->related_source('cds')->columns
4416 { +{ "cds.genre.$_" => "genre.$_" } }
4417 $schema->source('Artist')->related_source('cds')->related_source('genre')->columns
4420 { +{ "cds.tracks.$_" => "tracks.$_" } }
4421 $schema->source('Artist')->related_source('cds')->related_source('tracks')->columns
4426 Both producing the following SQL:
4428 SELECT me.artistid, me.name, me.rank, me.charfield,
4429 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track,
4430 genre.genreid, genre.name,
4431 tracks.trackid, tracks.cd, tracks.position, tracks.title, tracks.last_updated_on, tracks.last_updated_at
4434 ON cds.artist = me.artistid
4435 LEFT JOIN genre genre
4436 ON genre.genreid = cds.genreid
4437 LEFT JOIN track tracks
4438 ON tracks.cd = cds.cdid
4439 ORDER BY me.artistid
4441 While L</prefetch> implies a L</join>, it is ok to mix the two together, as
4442 the arguments are properly merged and generally do the right thing. For
4443 example, you may want to do the following:
4445 my $artists_and_cds_without_genre = $schema->resultset('Artist')->search(
4446 { 'genre.genreid' => undef },
4448 join => { cds => 'genre' },
4453 Which generates the following SQL:
4455 SELECT me.artistid, me.name, me.rank, me.charfield,
4456 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track
4459 ON cds.artist = me.artistid
4460 LEFT JOIN genre genre
4461 ON genre.genreid = cds.genreid
4462 WHERE genre.genreid IS NULL
4463 ORDER BY me.artistid
4465 For a more in-depth discussion, see L</PREFETCHING>.
4471 =item Value: $source_alias
4475 Sets the source alias for the query. Normally, this defaults to C<me>, but
4476 nested search queries (sub-SELECTs) might need specific aliases set to
4477 reference inner queries. For example:
4480 ->related_resultset('CDs')
4481 ->related_resultset('Tracks')
4483 'track.id' => { -ident => 'none_search.id' },
4487 my $ids = $self->search({
4490 alias => 'none_search',
4491 group_by => 'none_search.id',
4492 })->get_column('id')->as_query;
4494 $self->search({ id => { -in => $ids } })
4496 This attribute is directly tied to L</current_source_alias>.
4506 Makes the resultset paged and specifies the page to retrieve. Effectively
4507 identical to creating a non-pages resultset and then calling ->page($page)
4510 If L</rows> attribute is not specified it defaults to 10 rows per page.
4512 When you have a paged resultset, L</count> will only return the number
4513 of rows in the page. To get the total, use the L</pager> and call
4514 C<total_entries> on it.
4524 Specifies the maximum number of rows for direct retrieval or the number of
4525 rows per page if the page attribute or method is used.
4531 =item Value: $offset
4535 Specifies the (zero-based) row number for the first row to be returned, or the
4536 of the first row of the first page if paging is used.
4538 =head2 software_limit
4542 =item Value: (0 | 1)
4546 When combined with L</rows> and/or L</offset> the generated SQL will not
4547 include any limit dialect stanzas. Instead the entire result will be selected
4548 as if no limits were specified, and DBIC will perform the limit locally, by
4549 artificially advancing and finishing the resulting L</cursor>.
4551 This is the recommended way of performing resultset limiting when no sane RDBMS
4552 implementation is available (e.g.
4553 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4554 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4560 =item Value: \@columns
4564 A arrayref of columns to group by. Can include columns of joined tables.
4566 group_by => [qw/ column1 column2 ... /]
4572 =item Value: $condition
4576 The HAVING operator specifies a B<secondary> condition applied to the set
4577 after the grouping calculations have been done. In other words it is a
4578 constraint just like L</where> (and accepting the same
4579 L<SQL::Abstract syntax|SQL::Abstract/WHERE CLAUSES>) applied to the data
4580 as it exists after GROUP BY has taken place. Specifying L</having> without
4581 L</group_by> is a logical mistake, and a fatal error on most RDBMS engines.
4585 having => { 'count_employee' => { '>=', 100 } }
4587 or with an in-place function in which case literal SQL is required:
4589 having => \[ 'count(employee) >= ?', 100 ]
4595 =item Value: (0 | 1)
4599 Set to 1 to automatically generate a L</group_by> clause based on the selection
4600 (including intelligent handling of L</order_by> contents). Note that the group
4601 criteria calculation takes place over the B<final> selection. This includes
4602 any L</+columns>, L</+select> or L</order_by> additions in subsequent
4603 L</search> calls, and standalone columns selected via
4604 L<DBIx::Class::ResultSetColumn> (L</get_column>). A notable exception are the
4605 extra selections specified via L</prefetch> - such selections are explicitly
4606 excluded from group criteria calculations.
4608 If the final ResultSet also explicitly defines a L</group_by> attribute, this
4609 setting is ignored and an appropriate warning is issued.
4613 Adds extra conditions to the resultset, combined with the preexisting C<WHERE>
4614 conditions, same as the B<first> argument to the L<search operator|/search>
4616 # only return rows WHERE deleted IS NULL for all searches
4617 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4619 Note that the above example is
4620 L<strongly discouraged|DBIx::Class::ResultSource/resultset_attributes>.
4624 Set to 1 to cache search results. This prevents extra SQL queries if you
4625 revisit rows in your ResultSet:
4627 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4629 while( my $artist = $resultset->next ) {
4633 $resultset->first; # without cache, this would issue a query
4635 By default, searches are not cached.
4637 For more examples of using these attributes, see
4638 L<DBIx::Class::Manual::Cookbook>.
4644 =item Value: ( 'update' | 'shared' | \$scalar )
4648 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4649 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4654 DBIx::Class supports arbitrary related data prefetching from multiple related
4655 sources. Any combination of relationship types and column sets are supported.
4656 If L<collapsing|/collapse> is requested, there is an additional requirement of
4657 selecting enough data to make every individual object uniquely identifiable.
4659 Here are some more involved examples, based on the following relationship map:
4662 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4663 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4664 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4666 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4668 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4672 my $rs = $schema->resultset('Tag')->search(
4681 The initial search results in SQL like the following:
4683 SELECT tag.*, cd.*, artist.* FROM tag
4684 JOIN cd ON tag.cd = cd.cdid
4685 JOIN artist ON cd.artist = artist.artistid
4687 L<DBIx::Class> has no need to go back to the database when we access the
4688 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4691 Simple prefetches will be joined automatically, so there is no need
4692 for a C<join> attribute in the above search.
4694 The L</prefetch> attribute can be used with any of the relationship types
4695 and multiple prefetches can be specified together. Below is a more complex
4696 example that prefetches a CD's artist, its liner notes (if present),
4697 the cover image, the tracks on that CD, and the guests on those
4700 my $rs = $schema->resultset('CD')->search(
4704 { artist => 'record_label'}, # belongs_to => belongs_to
4705 'liner_note', # might_have
4706 'cover_image', # has_one
4707 { tracks => 'guests' }, # has_many => has_many
4712 This will produce SQL like the following:
4714 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4718 ON artist.artistid = me.artistid
4719 JOIN record_label record_label
4720 ON record_label.labelid = artist.labelid
4721 LEFT JOIN track tracks
4722 ON tracks.cdid = me.cdid
4723 LEFT JOIN guest guests
4724 ON guests.trackid = track.trackid
4725 LEFT JOIN liner_notes liner_note
4726 ON liner_note.cdid = me.cdid
4727 JOIN cd_artwork cover_image
4728 ON cover_image.cdid = me.cdid
4731 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4732 C<tracks>, and C<guests> of the CD will all be available through the
4733 relationship accessors without the need for additional queries to the
4738 Prefetch does a lot of deep magic. As such, it may not behave exactly
4739 as you might expect.
4745 Prefetch uses the L</cache> to populate the prefetched relationships. This
4746 may or may not be what you want.
4750 If you specify a condition on a prefetched relationship, ONLY those
4751 rows that match the prefetched condition will be fetched into that relationship.
4752 This means that adding prefetch to a search() B<may alter> what is returned by
4753 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4755 my $artist_rs = $schema->resultset('Artist')->search({
4761 my $count = $artist_rs->first->cds->count;
4763 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4765 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4767 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4769 That cmp_ok() may or may not pass depending on the datasets involved. In other
4770 words the C<WHERE> condition would apply to the entire dataset, just like
4771 it would in regular SQL. If you want to add a condition only to the "right side"
4772 of a C<LEFT JOIN> - consider declaring and using a L<relationship with a custom
4773 condition|DBIx::Class::Relationship::Base/condition>
4777 =head1 DBIC BIND VALUES
4779 Because DBIC may need more information to bind values than just the column name
4780 and value itself, it uses a special format for both passing and receiving bind
4781 values. Each bind value should be composed of an arrayref of
4782 C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
4788 If present (in any form), this is what is being passed directly to bind_param.
4789 Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
4790 a single numerical type, while DBD::Pg takes a hashref if bind options.)
4792 If this is specified, all other bind options described below are ignored.
4796 If present, this is used to infer the actual bind attribute by passing to
4797 C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
4798 "data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
4800 Note that the data type is somewhat freeform (hence the sqlt_ prefix);
4801 currently drivers are expected to "Do the Right Thing" when given a common
4802 datatype name. (Not ideal, but that's what we got at this point.)
4806 Currently used to correctly allocate buffers for bind_param_inout().
4807 Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
4808 or to a sensible value based on the "data_type".
4812 Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
4813 explicitly specified they are never overridden). Also used by some weird DBDs,
4814 where the column name should be available at bind_param time (e.g. Oracle).
4818 For backwards compatibility and convenience, the following shortcuts are
4821 [ $name => $val ] === [ { dbic_colname => $name }, $val ]
4822 [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
4823 [ undef, $val ] === [ {}, $val ]
4824 $val === [ {}, $val ]
4826 =head1 FURTHER QUESTIONS?
4828 Check the list of L<additional DBIC resources|DBIx::Class/GETTING HELP/SUPPORT>.
4830 =head1 COPYRIGHT AND LICENSE
4832 This module is free software L<copyright|DBIx::Class/COPYRIGHT AND LICENSE>
4833 by the L<DBIx::Class (DBIC) authors|DBIx::Class/AUTHORS>. You can
4834 redistribute it and/or modify it under the same terms as the
4835 L<DBIx::Class library|DBIx::Class/COPYRIGHT AND LICENSE>.