1 package DBIx::Class::ResultSet;
5 use base qw/DBIx::Class/;
7 use DBIx::Class::ResultSetColumn;
8 use Scalar::Util qw/blessed weaken reftype/;
9 use DBIx::Class::_Util qw(
10 fail_on_internal_wantarray fail_on_internal_call UNRESOLVABLE_CONDITION
13 use Data::Compare (); # no imports!!! guard against insane architecture
15 # not importing first() as it will clash with our own method
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/Source> 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 (ref $_[0]) ne '') ) {
446 ($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 ref $_[$i] ne '');
465 # see if we can keep the cache (no $rs changes)
467 my %safe = (alias => 1, cache => 1);
468 if ( ! List::Util::first { !$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 if (List::Util::first { exists $call_attrs->{$_} } qw/columns cols select as/) {
493 delete @{$old_attrs}{(@selector_attrs, '_dark_selector')};
496 # Normalize the new selector list (operates on the passed-in attr structure)
497 # Need to do it on every chain instead of only once on _resolved_attrs, in
498 # order to allow detection of empty vs partial 'as'
499 $call_attrs->{_dark_selector} = $old_attrs->{_dark_selector}
500 if $old_attrs->{_dark_selector};
501 $self->_normalize_selection ($call_attrs);
503 # start with blind overwriting merge, exclude selector attrs
504 $new_attrs = { %{$old_attrs}, %{$call_attrs} };
505 delete @{$new_attrs}{@selector_attrs};
507 for (@selector_attrs) {
508 $new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
509 if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
512 # older deprecated name, use only if {columns} is not there
513 if (my $c = delete $new_attrs->{cols}) {
514 carp_unique( "Resultset attribute 'cols' is deprecated, use 'columns' instead" );
515 if ($new_attrs->{columns}) {
516 carp "Resultset specifies both the 'columns' and the legacy 'cols' attributes - ignoring 'cols'";
519 $new_attrs->{columns} = $c;
524 # join/prefetch use their own crazy merging heuristics
525 foreach my $key (qw/join prefetch/) {
526 $new_attrs->{$key} = $self->_merge_joinpref_attr($old_attrs->{$key}, $call_attrs->{$key})
527 if exists $call_attrs->{$key};
530 # stack binds together
531 $new_attrs->{bind} = [ @{ $old_attrs->{bind} || [] }, @{ $call_attrs->{bind} || [] } ];
535 for ($old_where, $call_cond) {
537 $new_attrs->{where} = $self->_stack_cond (
538 $_, $new_attrs->{where}
543 if (defined $old_having) {
544 $new_attrs->{having} = $self->_stack_cond (
545 $old_having, $new_attrs->{having}
549 my $rs = (ref $self)->new($rsrc, $new_attrs);
551 $rs->set_cache($cache) if ($cache);
557 sub _normalize_selection {
558 my ($self, $attrs) = @_;
561 if ( exists $attrs->{include_columns} ) {
562 carp_unique( "Resultset attribute 'include_columns' is deprecated, use '+columns' instead" );
563 $attrs->{'+columns'} = $self->_merge_attr(
564 $attrs->{'+columns'}, delete $attrs->{include_columns}
568 # columns are always placed first, however
570 # Keep the X vs +X separation until _resolved_attrs time - this allows to
571 # delay the decision on whether to use a default select list ($rsrc->columns)
572 # allowing stuff like the remove_columns helper to work
574 # select/as +select/+as pairs need special handling - the amount of select/as
575 # elements in each pair does *not* have to be equal (think multicolumn
576 # selectors like distinct(foo, bar) ). If the selector is bare (no 'as'
577 # supplied at all) - try to infer the alias, either from the -as parameter
578 # of the selector spec, or use the parameter whole if it looks like a column
579 # name (ugly legacy heuristic). If all fails - leave the selector bare (which
580 # is ok as well), but make sure no more additions to the 'as' chain take place
581 for my $pref ('', '+') {
583 my ($sel, $as) = map {
584 my $key = "${pref}${_}";
586 my $val = [ ref $attrs->{$key} eq 'ARRAY'
588 : $attrs->{$key} || ()
590 delete $attrs->{$key};
594 if (! @$as and ! @$sel ) {
597 elsif (@$as and ! @$sel) {
598 $self->throw_exception(
599 "Unable to handle ${pref}as specification (@$as) without a corresponding ${pref}select"
603 # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
604 # if any @$as has been supplied we assume the user knows what (s)he is doing
605 # and blindly keep stacking up pieces
606 unless ($attrs->{_dark_selector}) {
609 if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
610 push @$as, $_->{-as};
612 # assume any plain no-space, no-parenthesis string to be a column spec
613 # FIXME - this is retarded but is necessary to support shit like 'count(foo)'
614 elsif ( ! ref $_ and $_ =~ /^ [^\s\(\)]+ $/x) {
617 # if all else fails - raise a flag that no more aliasing will be allowed
619 $attrs->{_dark_selector} = {
621 string => ($dark_sel_dumper ||= do {
622 require Data::Dumper::Concise;
623 Data::Dumper::Concise::DumperObject()->Indent(0);
624 })->Values([$_])->Dump
632 elsif (@$as < @$sel) {
633 $self->throw_exception(
634 "Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
637 elsif ($pref and $attrs->{_dark_selector}) {
638 $self->throw_exception(
639 "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
645 $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
646 $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
651 my ($self, $left, $right) = @_;
654 (ref $_ eq 'ARRAY' and !@$_)
656 (ref $_ eq 'HASH' and ! keys %$_)
657 ) and $_ = undef for ($left, $right);
659 # either on of the two undef or both undef
660 if ( ( (defined $left) xor (defined $right) ) or ! defined $left ) {
661 return defined $left ? $left : $right;
664 my $cond = $self->result_source->schema->storage->_collapse_cond({ -and => [$left, $right] });
666 for my $c (grep { ref $cond->{$_} eq 'ARRAY' and ($cond->{$_}[0]||'') eq '-and' } keys %$cond) {
668 my @vals = sort @{$cond->{$c}}[ 1..$#{$cond->{$c}} ];
669 my @fin = shift @vals;
672 push @fin, $v unless Data::Compare::Compare( $fin[-1], $v );
675 $cond->{$c} = (@fin == 1) ? $fin[0] : [-and => @fin ];
681 =head2 search_literal
683 B<CAVEAT>: C<search_literal> is provided for Class::DBI compatibility and
684 should only be used in that context. C<search_literal> is a convenience
685 method. It is equivalent to calling C<< $schema->search(\[]) >>, but if you
686 want to ensure columns are bound correctly, use L</search>.
688 See L<DBIx::Class::Manual::Cookbook/SEARCHING> and
689 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
690 require C<search_literal>.
694 =item Arguments: $sql_fragment, @standalone_bind_values
696 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
700 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
701 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
703 Pass a literal chunk of SQL to be added to the conditional part of the
706 Example of how to use C<search> instead of C<search_literal>
708 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
709 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
714 my ($self, $sql, @bind) = @_;
716 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
719 return $self->search(\[ $sql, map [ {} => $_ ], @bind ], ($attr || () ));
726 =item Arguments: \%columns_values | @pk_values, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
728 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
732 Finds and returns a single row based on supplied criteria. Takes either a
733 hashref with the same format as L</create> (including inference of foreign
734 keys from related objects), or a list of primary key values in the same
735 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
736 declaration on the L</result_source>.
738 In either case an attempt is made to combine conditions already existing on
739 the resultset with the condition passed to this method.
741 To aid with preparing the correct query for the storage you may supply the
742 C<key> attribute, which is the name of a
743 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
744 unique constraint corresponding to the
745 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
746 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
747 to construct a query that satisfies the named unique constraint fully (
748 non-NULL values for each column member of the constraint) an exception is
751 If no C<key> is specified, the search is carried over all unique constraints
752 which are fully defined by the available condition.
754 If no such constraint is found, C<find> currently defaults to a simple
755 C<< search->(\%column_values) >> which may or may not do what you expect.
756 Note that this fallback behavior may be deprecated in further versions. If
757 you need to search with arbitrary conditions - use L</search>. If the query
758 resulting from this fallback produces more than one row, a warning to the
759 effect is issued, though only the first row is constructed and returned as
762 In addition to C<key>, L</find> recognizes and applies standard
763 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
765 Note that if you have extra concerns about the correctness of the resulting
766 query you need to specify the C<key> attribute and supply the entire condition
767 as an argument to find (since it is not always possible to perform the
768 combination of the resultset condition with the supplied one, especially if
769 the resultset condition contains literal sql).
771 For example, to find a row by its primary key:
773 my $cd = $schema->resultset('CD')->find(5);
775 You can also find a row by a specific unique constraint:
777 my $cd = $schema->resultset('CD')->find(
779 artist => 'Massive Attack',
780 title => 'Mezzanine',
782 { key => 'cd_artist_title' }
785 See also L</find_or_create> and L</update_or_create>.
791 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
793 my $rsrc = $self->result_source;
796 if (exists $attrs->{key}) {
797 $constraint_name = defined $attrs->{key}
799 : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
803 # Parse out the condition from input
806 if (ref $_[0] eq 'HASH') {
807 $call_cond = { %{$_[0]} };
810 # if only values are supplied we need to default to 'primary'
811 $constraint_name = 'primary' unless defined $constraint_name;
813 my @c_cols = $rsrc->unique_constraint_columns($constraint_name);
815 $self->throw_exception(
816 "No constraint columns, maybe a malformed '$constraint_name' constraint?"
819 $self->throw_exception (
820 'find() expects either a column/value hashref, or a list of values '
821 . "corresponding to the columns of the specified unique constraint '$constraint_name'"
822 ) unless @c_cols == @_;
824 @{$call_cond}{@c_cols} = @_;
827 # process relationship data if any
828 for my $key (keys %$call_cond) {
830 length ref($call_cond->{$key})
832 my $relinfo = $rsrc->relationship_info($key)
834 # implicitly skip has_many's (likely MC)
835 (ref (my $val = delete $call_cond->{$key}) ne 'ARRAY' )
837 my ($rel_cond, $crosstable) = $rsrc->_resolve_condition(
838 $relinfo->{cond}, $val, $key, $key
841 $self->throw_exception("Complex condition via relationship '$key' is unsupported in find()")
842 if $crosstable or ref($rel_cond) ne 'HASH';
844 # supplement condition
845 # relationship conditions take precedence (?)
846 @{$call_cond}{keys %$rel_cond} = values %$rel_cond;
850 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
852 if (defined $constraint_name) {
853 $final_cond = $self->_qualify_cond_columns (
855 $self->result_source->_minimal_valueset_satisfying_constraint(
856 constraint_name => $constraint_name,
857 values => ($self->_merge_with_rscond($call_cond))[0],
864 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
865 # This means that we got here after a merger of relationship conditions
866 # in ::Relationship::Base::search_related (the row method), and furthermore
867 # the relationship is of the 'single' type. This means that the condition
868 # provided by the relationship (already attached to $self) is sufficient,
869 # as there can be only one row in the database that would satisfy the
873 my (@unique_queries, %seen_column_combinations, $ci, @fc_exceptions);
875 # no key was specified - fall down to heuristics mode:
876 # run through all unique queries registered on the resultset, and
877 # 'OR' all qualifying queries together
879 # always start from 'primary' if it exists at all
880 for my $c_name ( sort {
882 : $b eq 'primary' ? 1
884 } $rsrc->unique_constraint_names) {
886 next if $seen_column_combinations{
887 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
891 push @unique_queries, $self->_qualify_cond_columns(
892 $self->result_source->_minimal_valueset_satisfying_constraint(
893 constraint_name => $c_name,
894 values => ($self->_merge_with_rscond($call_cond))[0],
895 columns_info => ($ci ||= $self->result_source->columns_info),
901 push @fc_exceptions, $_ if $_ =~ /\bFilterColumn\b/;
906 @unique_queries ? \@unique_queries
907 : @fc_exceptions ? $self->throw_exception(join "; ", map { $_ =~ /(.*) at .+ line \d+$/s } @fc_exceptions )
908 : $self->_non_unique_find_fallback ($call_cond, $attrs)
912 # Run the query, passing the result_class since it should propagate for find
913 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
914 if ($rs->_resolved_attrs->{collapse}) {
916 carp "Query returned more than one row" if $rs->next;
924 # This is a stop-gap method as agreed during the discussion on find() cleanup:
925 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
927 # It is invoked when find() is called in legacy-mode with insufficiently-unique
928 # condition. It is provided for overrides until a saner way forward is devised
930 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
931 # the road. Please adjust your tests accordingly to catch this situation early
932 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
934 # The method will not be removed without an adequately complete replacement
935 # for strict-mode enforcement
936 sub _non_unique_find_fallback {
937 my ($self, $cond, $attrs) = @_;
939 return $self->_qualify_cond_columns(
941 exists $attrs->{alias}
943 : $self->{attrs}{alias}
948 sub _qualify_cond_columns {
949 my ($self, $cond, $alias) = @_;
951 my %aliased = %$cond;
952 for (keys %aliased) {
953 $aliased{"$alias.$_"} = delete $aliased{$_}
960 sub _build_unique_cond {
962 '_build_unique_cond is a private method, and moreover is about to go '
963 . 'away. Please contact the development team at %s if you believe you '
964 . 'have a genuine use for this method, in order to discuss alternatives.',
965 DBIx::Class::_ENV_::HELP_URL,
968 my ($self, $constraint_name, $cond, $croak_on_null) = @_;
970 $self->result_source->_minimal_valueset_satisfying_constraint(
971 constraint_name => $constraint_name,
973 carp_on_nulls => !$croak_on_null
977 =head2 search_related
981 =item Arguments: $rel_name, $cond?, L<\%attrs?|/ATTRIBUTES>
983 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
987 $new_rs = $cd_rs->search_related('artist', {
991 Searches the specified relationship, optionally specifying a condition and
992 attributes for matching records. See L</ATTRIBUTES> for more information.
994 In list context, C<< ->all() >> is called implicitly on the resultset, thus
995 returning a list of result objects instead. To avoid that, use L</search_related_rs>.
997 See also L</search_related_rs>.
1001 sub search_related {
1002 return shift->related_resultset(shift)->search(@_);
1005 =head2 search_related_rs
1007 This method works exactly the same as search_related, except that
1008 it guarantees a resultset, even in list context.
1012 sub search_related_rs {
1013 return shift->related_resultset(shift)->search_rs(@_);
1020 =item Arguments: none
1022 =item Return Value: L<$cursor|DBIx::Class::Cursor>
1026 Returns a storage-driven cursor to the given resultset. See
1027 L<DBIx::Class::Cursor> for more information.
1034 return $self->{cursor} ||= do {
1035 my $attrs = $self->_resolved_attrs;
1036 $self->result_source->storage->select(
1037 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
1046 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1048 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1052 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1054 Inflates the first result without creating a cursor if the resultset has
1055 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1058 While this method can take an optional search condition (just like L</search>)
1059 being a fast-code-path it does not recognize search attributes. If you need to
1060 add extra joins or similar, call L</search> and then chain-call L</single> on the
1061 L<DBIx::Class::ResultSet> returned.
1067 As of 0.08100, this method enforces the assumption that the preceding
1068 query returns only one row. If more than one row is returned, you will receive
1071 Query returned more than one row
1073 In this case, you should be using L</next> or L</find> instead, or if you really
1074 know what you are doing, use the L</rows> attribute to explicitly limit the size
1077 This method will also throw an exception if it is called on a resultset prefetching
1078 has_many, as such a prefetch implies fetching multiple rows from the database in
1079 order to assemble the resulting object.
1086 my ($self, $where) = @_;
1088 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1091 my $attrs = { %{$self->_resolved_attrs} };
1093 $self->throw_exception(
1094 'single() can not be used on resultsets collapsing a has_many. Use find( \%cond ) or next() instead'
1095 ) if $attrs->{collapse};
1098 if (defined $attrs->{where}) {
1101 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1102 $where, delete $attrs->{where} ]
1105 $attrs->{where} = $where;
1109 my $data = [ $self->result_source->storage->select_single(
1110 $attrs->{from}, $attrs->{select},
1111 $attrs->{where}, $attrs
1114 return undef unless @$data;
1115 $self->{_stashed_rows} = [ $data ];
1116 $self->_construct_results->[0];
1123 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1125 =item Return Value: L<$resultsetcolumn|DBIx::Class::ResultSetColumn>
1129 my $max_length = $rs->get_column('length')->max;
1131 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1136 my ($self, $column) = @_;
1137 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
1145 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1147 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1151 # WHERE title LIKE '%blue%'
1152 $cd_rs = $rs->search_like({ title => '%blue%'});
1154 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1155 that this is simply a convenience method retained for ex Class::DBI users.
1156 You most likely want to use L</search> with specific operators.
1158 For more information, see L<DBIx::Class::Manual::Cookbook>.
1160 This method is deprecated and will be removed in 0.09. Use L</search()>
1161 instead. An example conversion is:
1163 ->search_like({ foo => 'bar' });
1167 ->search({ foo => { like => 'bar' } });
1174 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1175 .' Instead use ->search({ x => { -like => "y%" } })'
1176 .' (note the outer pair of {}s - they are important!)'
1178 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1179 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1180 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1181 return $class->search($query, { %$attrs });
1188 =item Arguments: $first, $last
1190 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1194 Returns a resultset or object list representing a subset of elements from the
1195 resultset slice is called on. Indexes are from 0, i.e., to get the first
1196 three records, call:
1198 my ($one, $two, $three) = $rs->slice(0, 2);
1203 my ($self, $min, $max) = @_;
1204 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1205 $attrs->{offset} = $self->{attrs}{offset} || 0;
1206 $attrs->{offset} += $min;
1207 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1208 return $self->search(undef, $attrs);
1215 =item Arguments: none
1217 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1221 Returns the next element in the resultset (C<undef> is there is none).
1223 Can be used to efficiently iterate over records in the resultset:
1225 my $rs = $schema->resultset('CD')->search;
1226 while (my $cd = $rs->next) {
1230 Note that you need to store the resultset object, and call C<next> on it.
1231 Calling C<< resultset('Table')->next >> repeatedly will always return the
1232 first record from the resultset.
1239 if (my $cache = $self->get_cache) {
1240 $self->{all_cache_position} ||= 0;
1241 return $cache->[$self->{all_cache_position}++];
1244 if ($self->{attrs}{cache}) {
1245 delete $self->{pager};
1246 $self->{all_cache_position} = 1;
1247 return ($self->all)[0];
1250 return shift(@{$self->{_stashed_results}}) if @{ $self->{_stashed_results}||[] };
1252 $self->{_stashed_results} = $self->_construct_results
1255 return shift @{$self->{_stashed_results}};
1258 # Constructs as many results as it can in one pass while respecting
1259 # cursor laziness. Several modes of operation:
1261 # * Always builds everything present in @{$self->{_stashed_rows}}
1262 # * If called with $fetch_all true - pulls everything off the cursor and
1263 # builds all result structures (or objects) in one pass
1264 # * If $self->_resolved_attrs->{collapse} is true, checks the order_by
1265 # and if the resultset is ordered properly by the left side:
1266 # * Fetches stuff off the cursor until the "master object" changes,
1267 # and saves the last extra row (if any) in @{$self->{_stashed_rows}}
1269 # * Just fetches, and collapses/constructs everything as if $fetch_all
1270 # was requested (there is no other way to collapse except for an
1272 # * If no collapse is requested - just get the next row, construct and
1274 sub _construct_results {
1275 my ($self, $fetch_all) = @_;
1277 my $rsrc = $self->result_source;
1278 my $attrs = $self->_resolved_attrs;
1283 ! $attrs->{order_by}
1287 my @pcols = $rsrc->primary_columns
1289 # default order for collapsing unless the user asked for something
1290 $attrs->{order_by} = [ map { join '.', $attrs->{alias}, $_} @pcols ];
1291 $attrs->{_ordered_for_collapse} = 1;
1292 $attrs->{_order_is_artificial} = 1;
1295 # this will be used as both initial raw-row collector AND as a RV of
1296 # _construct_results. Not regrowing the array twice matters a lot...
1297 # a surprising amount actually
1298 my $rows = delete $self->{_stashed_rows};
1300 my $cursor; # we may not need one at all
1302 my $did_fetch_all = $fetch_all;
1305 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1306 $rows = [ ($rows ? @$rows : ()), $self->cursor->all ];
1308 elsif( $attrs->{collapse} ) {
1310 # a cursor will need to be closed over in case of collapse
1311 $cursor = $self->cursor;
1313 $attrs->{_ordered_for_collapse} = (
1319 ->_extract_colinfo_of_stable_main_source_order_by_portion($attrs)
1321 ) unless defined $attrs->{_ordered_for_collapse};
1323 if (! $attrs->{_ordered_for_collapse}) {
1326 # instead of looping over ->next, use ->all in stealth mode
1327 # *without* calling a ->reset afterwards
1328 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1329 if (! $cursor->{_done}) {
1330 $rows = [ ($rows ? @$rows : ()), $cursor->all ];
1331 $cursor->{_done} = 1;
1336 if (! $did_fetch_all and ! @{$rows||[]} ) {
1337 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1338 $cursor ||= $self->cursor;
1339 if (scalar (my @r = $cursor->next) ) {
1344 return undef unless @{$rows||[]};
1346 # sanity check - people are too clever for their own good
1347 if ($attrs->{collapse} and my $aliastypes = $attrs->{_last_sqlmaker_alias_map} ) {
1349 my $multiplied_selectors;
1350 for my $sel_alias ( grep { $_ ne $attrs->{alias} } keys %{ $aliastypes->{selecting} } ) {
1352 $aliastypes->{multiplying}{$sel_alias}
1354 $aliastypes->{premultiplied}{$sel_alias}
1356 $multiplied_selectors->{$_} = 1 for values %{$aliastypes->{selecting}{$sel_alias}{-seen_columns}}
1360 for my $i (0 .. $#{$attrs->{as}} ) {
1361 my $sel = $attrs->{select}[$i];
1363 if (ref $sel eq 'SCALAR') {
1366 elsif( ref $sel eq 'REF' and ref $$sel eq 'ARRAY' ) {
1370 $self->throw_exception(
1371 'Result collapse not possible - selection from a has_many source redirected to the main object'
1372 ) if ($multiplied_selectors->{$sel} and $attrs->{as}[$i] !~ /\./);
1376 # hotspot - skip the setter
1377 my $res_class = $self->_result_class;
1379 my $inflator_cref = $self->{_result_inflator}{cref} ||= do {
1380 $res_class->can ('inflate_result')
1381 or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
1384 my $infmap = $attrs->{as};
1386 $self->{_result_inflator}{is_core_row} = ( (
1389 ( \&DBIx::Class::Row::inflate_result || die "No ::Row::inflate_result() - can't happen" )
1390 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_core_row};
1392 $self->{_result_inflator}{is_hri} = ( (
1393 ! $self->{_result_inflator}{is_core_row}
1396 require DBIx::Class::ResultClass::HashRefInflator
1398 DBIx::Class::ResultClass::HashRefInflator->can('inflate_result')
1400 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_hri};
1403 if ($attrs->{_simple_passthrough_construction}) {
1404 # construct a much simpler array->hash folder for the one-table HRI cases right here
1405 if ($self->{_result_inflator}{is_hri}) {
1406 for my $r (@$rows) {
1407 $r = { map { $infmap->[$_] => $r->[$_] } 0..$#$infmap };
1410 # FIXME SUBOPTIMAL this is a very very very hot spot
1411 # while rather optimal we can *still* do much better, by
1412 # building a smarter Row::inflate_result(), and
1413 # switch to feeding it data via a much leaner interface
1415 # crude unscientific benchmarking indicated the shortcut eval is not worth it for
1416 # this particular resultset size
1417 elsif ( $self->{_result_inflator}{is_core_row} and @$rows < 60 ) {
1418 for my $r (@$rows) {
1419 $r = $inflator_cref->($res_class, $rsrc, { map { $infmap->[$_] => $r->[$_] } (0..$#$infmap) } );
1424 ( $self->{_result_inflator}{is_core_row}
1425 ? '$_ = $inflator_cref->($res_class, $rsrc, { %s }) for @$rows'
1426 # a custom inflator may be a multiplier/reductor - put it in direct list ctx
1427 : '@$rows = map { $inflator_cref->($res_class, $rsrc, { %s } ) } @$rows'
1429 ( join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap ) )
1435 $self->{_result_inflator}{is_hri} ? 'hri'
1436 : $self->{_result_inflator}{is_core_row} ? 'classic_pruning'
1437 : 'classic_nonpruning'
1440 # $args and $attrs to _mk_row_parser are separated to delineate what is
1441 # core collapser stuff and what is dbic $rs specific
1442 @{$self->{_row_parser}{$parser_type}}{qw(cref nullcheck)} = $rsrc->_mk_row_parser({
1444 inflate_map => $infmap,
1445 collapse => $attrs->{collapse},
1446 premultiplied => $attrs->{_main_source_premultiplied},
1447 hri_style => $self->{_result_inflator}{is_hri},
1448 prune_null_branches => $self->{_result_inflator}{is_hri} || $self->{_result_inflator}{is_core_row},
1449 }, $attrs) unless $self->{_row_parser}{$parser_type}{cref};
1451 # column_info metadata historically hasn't been too reliable.
1452 # We need to start fixing this somehow (the collapse resolver
1453 # can't work without it). Add an explicit check for the *main*
1454 # result, hopefully this will gradually weed out such errors
1456 # FIXME - this is a temporary kludge that reduces performance
1457 # It is however necessary for the time being
1458 my ($unrolled_non_null_cols_to_check, $err);
1460 if (my $check_non_null_cols = $self->{_row_parser}{$parser_type}{nullcheck} ) {
1463 'Collapse aborted due to invalid ResultSource metadata - the following '
1464 . 'selections are declared non-nullable but NULLs were retrieved: '
1468 COL: for my $i (@$check_non_null_cols) {
1469 ! defined $_->[$i] and push @violating_idx, $i and next COL for @$rows;
1472 $self->throw_exception( $err . join (', ', map { "'$infmap->[$_]'" } @violating_idx ) )
1475 $unrolled_non_null_cols_to_check = join (',', @$check_non_null_cols);
1479 ($did_fetch_all or ! $attrs->{collapse}) ? undef
1480 : defined $unrolled_non_null_cols_to_check ? eval sprintf <<'EOS', $unrolled_non_null_cols_to_check
1482 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1483 my @r = $cursor->next or return;
1484 if (my @violating_idx = grep { ! defined $r[$_] } (%s) ) {
1485 $self->throw_exception( $err . join (', ', map { "'$infmap->[$_]'" } @violating_idx ) )
1491 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1492 my @r = $cursor->next or return;
1497 $self->{_row_parser}{$parser_type}{cref}->(
1499 $next_cref ? ( $next_cref, $self->{_stashed_rows} = [] ) : (),
1502 # simple in-place substitution, does not regrow $rows
1503 if ($self->{_result_inflator}{is_core_row}) {
1504 $_ = $inflator_cref->($res_class, $rsrc, @$_) for @$rows
1506 # Special-case multi-object HRI - there is no $inflator_cref pass at all
1507 elsif ( ! $self->{_result_inflator}{is_hri} ) {
1508 # the inflator may be a multiplier/reductor - put it in list ctx
1509 @$rows = map { $inflator_cref->($res_class, $rsrc, @$_) } @$rows;
1513 # The @$rows check seems odd at first - why wouldn't we want to warn
1514 # regardless? The issue is things like find() etc, where the user
1515 # *knows* only one result will come back. In these cases the ->all
1516 # is not a pessimization, but rather something we actually want
1518 'Unable to properly collapse has_many results in iterator mode due '
1519 . 'to order criteria - performed an eager cursor slurp underneath. '
1520 . 'Consider using ->all() instead'
1521 ) if ( ! $fetch_all and @$rows > 1 );
1526 =head2 result_source
1530 =item Arguments: L<$result_source?|DBIx::Class::ResultSource>
1532 =item Return Value: L<$result_source|DBIx::Class::ResultSource>
1536 An accessor for the primary ResultSource object from which this ResultSet
1543 =item Arguments: $result_class?
1545 =item Return Value: $result_class
1549 An accessor for the class to use when creating result objects. Defaults to
1550 C<< result_source->result_class >> - which in most cases is the name of the
1551 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1553 Note that changing the result_class will also remove any components
1554 that were originally loaded in the source class via
1555 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1556 in the original source class will not run.
1561 my ($self, $result_class) = @_;
1562 if ($result_class) {
1564 # don't fire this for an object
1565 $self->ensure_class_loaded($result_class)
1566 unless ref($result_class);
1568 if ($self->get_cache) {
1569 carp_unique('Changing the result_class of a ResultSet instance with cached results is a noop - the cache contents will not be altered');
1571 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1572 elsif ($self->{cursor} && $self->{cursor}{_pos}) {
1573 $self->throw_exception('Changing the result_class of a ResultSet instance with an active cursor is not supported');
1576 $self->_result_class($result_class);
1578 delete $self->{_result_inflator};
1580 $self->_result_class;
1587 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1589 =item Return Value: $count
1593 Performs an SQL C<COUNT> with the same query as the resultset was built
1594 with to find the number of elements. Passing arguments is equivalent to
1595 C<< $rs->search ($cond, \%attrs)->count >>
1601 return $self->search(@_)->count if @_ and defined $_[0];
1602 return scalar @{ $self->get_cache } if $self->get_cache;
1604 my $attrs = { %{ $self->_resolved_attrs } };
1606 # this is a little optimization - it is faster to do the limit
1607 # adjustments in software, instead of a subquery
1608 my ($rows, $offset) = delete @{$attrs}{qw/rows offset/};
1611 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1612 $crs = $self->_count_subq_rs ($attrs);
1615 $crs = $self->_count_rs ($attrs);
1617 my $count = $crs->next;
1619 $count -= $offset if $offset;
1620 $count = $rows if $rows and $rows < $count;
1621 $count = 0 if ($count < 0);
1630 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1632 =item Return Value: L<$count_rs|DBIx::Class::ResultSetColumn>
1636 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1637 This can be very handy for subqueries:
1639 ->search( { amount => $some_rs->count_rs->as_query } )
1641 As with regular resultsets the SQL query will be executed only after
1642 the resultset is accessed via L</next> or L</all>. That would return
1643 the same single value obtainable via L</count>.
1649 return $self->search(@_)->count_rs if @_;
1651 # this may look like a lack of abstraction (count() does about the same)
1652 # but in fact an _rs *must* use a subquery for the limits, as the
1653 # software based limiting can not be ported if this $rs is to be used
1654 # in a subquery itself (i.e. ->as_query)
1655 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1656 return $self->_count_subq_rs($self->{_attrs});
1659 return $self->_count_rs($self->{_attrs});
1664 # returns a ResultSetColumn object tied to the count query
1667 my ($self, $attrs) = @_;
1669 my $rsrc = $self->result_source;
1671 my $tmp_attrs = { %$attrs };
1672 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1673 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1675 # overwrite the selector (supplied by the storage)
1676 $rsrc->resultset_class->new($rsrc, {
1678 select => $rsrc->storage->_count_select ($rsrc, $attrs),
1680 })->get_column ('count');
1684 # same as above but uses a subquery
1686 sub _count_subq_rs {
1687 my ($self, $attrs) = @_;
1689 my $rsrc = $self->result_source;
1691 my $sub_attrs = { %$attrs };
1692 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1693 delete @{$sub_attrs}{qw/collapse columns as select order_by for/};
1695 # if we multi-prefetch we group_by something unique, as this is what we would
1696 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1697 if ( $attrs->{collapse} ) {
1698 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1699 $rsrc->_identifying_column_set || $self->throw_exception(
1700 'Unable to construct a unique group_by criteria properly collapsing the '
1701 . 'has_many prefetch before count()'
1706 # Calculate subquery selector
1707 if (my $g = $sub_attrs->{group_by}) {
1709 my $sql_maker = $rsrc->storage->sql_maker;
1711 # necessary as the group_by may refer to aliased functions
1713 for my $sel (@{$attrs->{select}}) {
1714 $sel_index->{$sel->{-as}} = $sel
1715 if (ref $sel eq 'HASH' and $sel->{-as});
1718 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1719 # also look for named aggregates referred in the having clause
1720 # having often contains scalarrefs - thus parse it out entirely
1722 if ($attrs->{having}) {
1723 local $sql_maker->{having_bind};
1724 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1725 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1726 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1727 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1728 # if we don't unset it we screw up retarded but unfortunately working
1729 # 'MAX(foo.bar)' => { '>', 3 }
1730 $sql_maker->{name_sep} = '';
1733 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1735 my $having_sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1738 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1739 # and if all fails for an utterly naive quoted scalar-with-function
1740 while ($having_sql =~ /
1741 $rquote $sep $lquote (.+?) $rquote
1743 [\s,] \w+ \. (\w+) [\s,]
1745 [\s,] $lquote (.+?) $rquote [\s,]
1747 my $part = $1 || $2 || $3; # one of them matched if we got here
1748 unless ($seen_having{$part}++) {
1755 my $colpiece = $sel_index->{$_} || $_;
1757 # unqualify join-based group_by's. Arcane but possible query
1758 # also horrible horrible hack to alias a column (not a func.)
1759 # (probably need to introduce SQLA syntax)
1760 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1763 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1765 push @{$sub_attrs->{select}}, $colpiece;
1769 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1770 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1773 return $rsrc->resultset_class
1774 ->new ($rsrc, $sub_attrs)
1776 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1777 ->get_column ('count');
1781 =head2 count_literal
1783 B<CAVEAT>: C<count_literal> is provided for Class::DBI compatibility and
1784 should only be used in that context. See L</search_literal> for further info.
1788 =item Arguments: $sql_fragment, @standalone_bind_values
1790 =item Return Value: $count
1794 Counts the results in a literal query. Equivalent to calling L</search_literal>
1795 with the passed arguments, then L</count>.
1799 sub count_literal { shift->search_literal(@_)->count; }
1805 =item Arguments: none
1807 =item Return Value: L<@result_objs|DBIx::Class::Manual::ResultClass>
1811 Returns all elements in the resultset.
1818 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1821 delete @{$self}{qw/_stashed_rows _stashed_results/};
1823 if (my $c = $self->get_cache) {
1827 $self->cursor->reset;
1829 my $objs = $self->_construct_results('fetch_all') || [];
1831 $self->set_cache($objs) if $self->{attrs}{cache};
1840 =item Arguments: none
1842 =item Return Value: $self
1846 Resets the resultset's cursor, so you can iterate through the elements again.
1847 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1855 delete @{$self}{qw/_stashed_rows _stashed_results/};
1856 $self->{all_cache_position} = 0;
1857 $self->cursor->reset;
1865 =item Arguments: none
1867 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1871 L<Resets|/reset> the resultset (causing a fresh query to storage) and returns
1872 an object for the first result (or C<undef> if the resultset is empty).
1877 return $_[0]->reset->next;
1883 # Determines whether and what type of subquery is required for the $rs operation.
1884 # If grouping is necessary either supplies its own, or verifies the current one
1885 # After all is done delegates to the proper storage method.
1887 sub _rs_update_delete {
1888 my ($self, $op, $values) = @_;
1890 my $rsrc = $self->result_source;
1891 my $storage = $rsrc->schema->storage;
1893 my $attrs = { %{$self->_resolved_attrs} };
1895 my $join_classifications;
1896 my ($existing_group_by) = delete @{$attrs}{qw(group_by _grouped_by_distinct)};
1898 # do we need a subquery for any reason?
1900 defined $existing_group_by
1902 # if {from} is unparseable wrap a subq
1903 ref($attrs->{from}) ne 'ARRAY'
1905 # limits call for a subq
1906 $self->_has_resolved_attr(qw/rows offset/)
1909 # simplify the joinmap, so we can further decide if a subq is necessary
1910 if (!$needs_subq and @{$attrs->{from}} > 1) {
1912 ($attrs->{from}, $join_classifications) =
1913 $storage->_prune_unused_joins ($attrs);
1915 # any non-pruneable non-local restricting joins imply subq
1916 $needs_subq = defined List::Util::first { $_ ne $attrs->{alias} } keys %{ $join_classifications->{restricting} || {} };
1919 # check if the head is composite (by now all joins are thrown out unless $needs_subq)
1921 (ref $attrs->{from}[0]) ne 'HASH'
1923 ref $attrs->{from}[0]{ $attrs->{from}[0]{-alias} }
1927 # do we need anything like a subquery?
1928 if (! $needs_subq) {
1929 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1930 # a condition containing 'me' or other table prefixes will not work
1931 # at all. Tell SQLMaker to dequalify idents via a gross hack.
1933 my $sqla = $rsrc->storage->sql_maker;
1934 local $sqla->{_dequalify_idents} = 1;
1935 \[ $sqla->_recurse_where($self->{cond}) ];
1939 # we got this far - means it is time to wrap a subquery
1940 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1942 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1948 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1949 delete $attrs->{$_} for qw/select as collapse/;
1950 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1952 # this will be consumed by the pruner waaaaay down the stack
1953 $attrs->{_force_prune_multiplying_joins} = 1;
1955 my $subrs = (ref $self)->new($rsrc, $attrs);
1957 if (@$idcols == 1) {
1958 $cond = { $idcols->[0] => { -in => $subrs->as_query } };
1960 elsif ($storage->_use_multicolumn_in) {
1961 # no syntax for calling this properly yet
1962 # !!! EXPERIMENTAL API !!! WILL CHANGE !!!
1963 $cond = $storage->sql_maker->_where_op_multicolumn_in (
1964 $idcols, # how do I convey a list of idents...? can binds reside on lhs?
1969 # if all else fails - get all primary keys and operate over a ORed set
1970 # wrap in a transaction for consistency
1971 # this is where the group_by/multiplication starts to matter
1975 # we do not need to check pre-multipliers, since if the premulti is there, its
1976 # parent (who is multi) will be there too
1977 keys %{ $join_classifications->{multiplying} || {} }
1979 # make sure if there is a supplied group_by it matches the columns compiled above
1980 # perfectly. Anything else can not be sanely executed on most databases so croak
1981 # right then and there
1982 if ($existing_group_by) {
1983 my @current_group_by = map
1984 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1989 join ("\x00", sort @current_group_by)
1991 join ("\x00", sort @{$attrs->{columns}} )
1993 $self->throw_exception (
1994 "You have just attempted a $op operation on a resultset which does group_by"
1995 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1996 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1997 . ' kind of queries. Please retry the operation with a modified group_by or'
1998 . ' without using one at all.'
2003 $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
2006 $guard = $storage->txn_scope_guard;
2008 for my $row ($subrs->cursor->all) {
2010 { $idcols->[$_] => $row->[$_] }
2017 my $res = $cond ? $storage->$op (
2019 $op eq 'update' ? $values : (),
2023 $guard->commit if $guard;
2032 =item Arguments: \%values
2034 =item Return Value: $underlying_storage_rv
2038 Sets the specified columns in the resultset to the supplied values in a
2039 single query. Note that this will not run any accessor/set_column/update
2040 triggers, nor will it update any result object instances derived from this
2041 resultset (this includes the contents of the L<resultset cache|/set_cache>
2042 if any). See L</update_all> if you need to execute any on-update
2043 triggers or cascades defined either by you or a
2044 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2046 The return value is a pass through of what the underlying
2047 storage backend returned, and may vary. See L<DBI/execute> for the most
2052 Note that L</update> does not process/deflate any of the values passed in.
2053 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
2054 ensure manually that any value passed to this method will stringify to
2055 something the RDBMS knows how to deal with. A notable example is the
2056 handling of L<DateTime> objects, for more info see:
2057 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
2062 my ($self, $values) = @_;
2063 $self->throw_exception('Values for update must be a hash')
2064 unless ref $values eq 'HASH';
2066 return $self->_rs_update_delete ('update', $values);
2073 =item Arguments: \%values
2075 =item Return Value: 1
2079 Fetches all objects and updates them one at a time via
2080 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
2081 triggers, while L</update> will not.
2086 my ($self, $values) = @_;
2087 $self->throw_exception('Values for update_all must be a hash')
2088 unless ref $values eq 'HASH';
2090 my $guard = $self->result_source->schema->txn_scope_guard;
2091 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
2100 =item Arguments: none
2102 =item Return Value: $underlying_storage_rv
2106 Deletes the rows matching this resultset in a single query. Note that this
2107 will not run any delete triggers, nor will it alter the
2108 L<in_storage|DBIx::Class::Row/in_storage> status of any result object instances
2109 derived from this resultset (this includes the contents of the
2110 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
2111 execute any on-delete triggers or cascades defined either by you or a
2112 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2114 The return value is a pass through of what the underlying storage backend
2115 returned, and may vary. See L<DBI/execute> for the most common case.
2121 $self->throw_exception('delete does not accept any arguments')
2124 return $self->_rs_update_delete ('delete');
2131 =item Arguments: none
2133 =item Return Value: 1
2137 Fetches all objects and deletes them one at a time via
2138 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2139 triggers, while L</delete> will not.
2145 $self->throw_exception('delete_all does not accept any arguments')
2148 my $guard = $self->result_source->schema->txn_scope_guard;
2149 $_->delete for $self->all;
2158 =item Arguments: [ \@column_list, \@row_values+ ] | [ \%col_data+ ]
2160 =item Return Value: L<\@result_objects|DBIx::Class::Manual::ResultClass> (scalar context) | L<@result_objects|DBIx::Class::Manual::ResultClass> (list context)
2164 Accepts either an arrayref of hashrefs or alternatively an arrayref of
2171 The context of this method call has an important effect on what is
2172 submitted to storage. In void context data is fed directly to fastpath
2173 insertion routines provided by the underlying storage (most often
2174 L<DBI/execute_for_fetch>), bypassing the L<new|DBIx::Class::Row/new> and
2175 L<insert|DBIx::Class::Row/insert> calls on the
2176 L<Result|DBIx::Class::Manual::ResultClass> class, including any
2177 augmentation of these methods provided by components. For example if you
2178 are using something like L<DBIx::Class::UUIDColumns> to create primary
2179 keys for you, you will find that your PKs are empty. In this case you
2180 will have to explicitly force scalar or list context in order to create
2185 In non-void (scalar or list) context, this method is simply a wrapper
2186 for L</create>. Depending on list or scalar context either a list of
2187 L<Result|DBIx::Class::Manual::ResultClass> objects or an arrayref
2188 containing these objects is returned.
2190 When supplying data in "arrayref of arrayrefs" invocation style, the
2191 first element should be a list of column names and each subsequent
2192 element should be a data value in the earlier specified column order.
2195 $schema->resultset("Artist")->populate([
2196 [ qw( artistid name ) ],
2197 [ 100, 'A Formally Unknown Singer' ],
2198 [ 101, 'A singer that jumped the shark two albums ago' ],
2199 [ 102, 'An actually cool singer' ],
2202 For the arrayref of hashrefs style each hashref should be a structure
2203 suitable for passing to L</create>. Multi-create is also permitted with
2206 $schema->resultset("Artist")->populate([
2207 { artistid => 4, name => 'Manufactured Crap', cds => [
2208 { title => 'My First CD', year => 2006 },
2209 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2212 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2213 { title => 'My parents sold me to a record company', year => 2005 },
2214 { title => 'Why Am I So Ugly?', year => 2006 },
2215 { title => 'I Got Surgery and am now Popular', year => 2007 }
2220 If you attempt a void-context multi-create as in the example above (each
2221 Artist also has the related list of CDs), and B<do not> supply the
2222 necessary autoinc foreign key information, this method will proxy to the
2223 less efficient L</create>, and then throw the Result objects away. In this
2224 case there are obviously no benefits to using this method over L</create>.
2233 # this is naive and just a quick check
2234 # the types will need to be checked more thoroughly when the
2235 # multi-source populate gets added
2236 if (ref $_[0] eq 'ARRAY') {
2237 return unless @{$_[0]};
2239 $data = $_[0] if (ref $_[0][0] eq 'HASH' or ref $_[0][0] eq 'ARRAY');
2242 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs')
2245 # FIXME - no cref handling
2246 # At this point assume either hashes or arrays
2248 if(defined wantarray) {
2251 $guard = $self->result_source->schema->storage->txn_scope_guard
2252 if ( @$data > 2 or ( @$data == 2 and ref $data->[0] eq 'ARRAY' ) );
2254 if (ref $data->[0] eq 'ARRAY') {
2256 { my $vals = $_; $self->new_result({ map { $data->[0][$_] => $vals->[$_] } 0..$#{$data->[0]} })->insert }
2257 @{$data}[1 .. $#$data]
2261 @results = map { $self->new_result($_)->insert } @$data;
2264 $guard->commit if $guard;
2265 return wantarray ? @results : \@results;
2268 # we have to deal with *possibly incomplete* related data
2269 # this means we have to walk the data structure twice
2270 # whether we want this or not
2271 # jnap, I hate you ;)
2272 my $rsrc = $self->result_source;
2273 my $rel_info = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2275 my ($colinfo, $colnames, $slices_with_rels);
2279 for my $i (0 .. $#$data) {
2281 my $current_slice_seen_rel_infos;
2283 ### Determine/Supplement collists
2284 ### BEWARE - This is a hot piece of code, a lot of weird idioms were used
2285 if( ref $data->[$i] eq 'ARRAY' ) {
2287 # positional(!) explicit column list
2290 $colinfo->{$data->[0][$_]} = { pos => $_, name => $data->[0][$_] } and push @$colnames, $data->[0][$_]
2291 for 0 .. $#{$data->[0]};
2298 for (values %$colinfo) {
2299 if ($_->{is_rel} ||= (
2300 $rel_info->{$_->{name}}
2303 ref $data->[$i][$_->{pos}] eq 'ARRAY'
2305 ref $data->[$i][$_->{pos}] eq 'HASH'
2307 ( defined blessed $data->[$i][$_->{pos}] and $data->[$i][$_->{pos}]->isa('DBIx::Class::Row') )
2313 # moar sanity check... sigh
2314 for ( ref $data->[$i][$_->{pos}] eq 'ARRAY' ? @{$data->[$i][$_->{pos}]} : $data->[$i][$_->{pos}] ) {
2315 if ( defined blessed $_ and $_->isa('DBIx::Class::Row' ) ) {
2316 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2317 return my $throwaway = $self->populate(@_);
2321 push @$current_slice_seen_rel_infos, $rel_info->{$_->{name}};
2326 if ($current_slice_seen_rel_infos) {
2327 push @$slices_with_rels, { map { $colnames->[$_] => $data->[$i][$_] } 0 .. $#$colnames };
2329 # this is needed further down to decide whether or not to fallback to create()
2330 $colinfo->{$colnames->[$_]}{seen_null} ||= ! defined $data->[$i][$_]
2331 for 0 .. $#$colnames;
2334 elsif( ref $data->[$i] eq 'HASH' ) {
2336 for ( sort keys %{$data->[$i]} ) {
2338 $colinfo->{$_} ||= do {
2340 $self->throw_exception("Column '$_' must be present in supplied explicit column list")
2341 if $data_start; # it will be 0 on AoH, 1 on AoA
2343 push @$colnames, $_;
2346 { pos => $#$colnames, name => $_ }
2349 if ($colinfo->{$_}{is_rel} ||= (
2353 ref $data->[$i]{$_} eq 'ARRAY'
2355 ref $data->[$i]{$_} eq 'HASH'
2357 ( defined blessed $data->[$i]{$_} and $data->[$i]{$_}->isa('DBIx::Class::Row') )
2363 # moar sanity check... sigh
2364 for ( ref $data->[$i]{$_} eq 'ARRAY' ? @{$data->[$i]{$_}} : $data->[$i]{$_} ) {
2365 if ( defined blessed $_ and $_->isa('DBIx::Class::Row' ) ) {
2366 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2367 return my $throwaway = $self->populate(@_);
2371 push @$current_slice_seen_rel_infos, $rel_info->{$_};
2375 if ($current_slice_seen_rel_infos) {
2376 push @$slices_with_rels, $data->[$i];
2378 # this is needed further down to decide whether or not to fallback to create()
2379 $colinfo->{$_}{seen_null} ||= ! defined $data->[$i]{$_}
2380 for keys %{$data->[$i]};
2384 $self->throw_exception('Unexpected populate() data structure member type: ' . ref $data->[$i] );
2388 { $_->{attrs}{is_depends_on} }
2389 @{ $current_slice_seen_rel_infos || [] }
2391 carp_unique("Fast-path populate() of belongs_to relationship data is not possible - falling back to regular create()");
2392 return my $throwaway = $self->populate(@_);
2396 if( $slices_with_rels ) {
2398 # need to exclude the rel "columns"
2399 $colnames = [ grep { ! $colinfo->{$_}{is_rel} } @$colnames ];
2401 # extra sanity check - ensure the main source is in fact identifiable
2402 # the localizing of nullability is insane, but oh well... the use-case is legit
2403 my $ci = $rsrc->columns_info($colnames);
2405 $ci->{$_} = { %{$ci->{$_}}, is_nullable => 0 }
2406 for grep { ! $colinfo->{$_}{seen_null} } keys %$ci;
2408 unless( $rsrc->_identifying_column_set($ci) ) {
2409 carp_unique("Fast-path populate() of non-uniquely identifiable rows with related data is not possible - falling back to regular create()");
2410 return my $throwaway = $self->populate(@_);
2414 ### inherit the data locked in the conditions of the resultset
2415 my ($rs_data) = $self->_merge_with_rscond({});
2416 delete @{$rs_data}{@$colnames}; # passed-in stuff takes precedence
2418 # if anything left - decompose rs_data
2420 if (keys %$rs_data) {
2421 push @$rs_data_vals, $rs_data->{$_}
2422 for sort keys %$rs_data;
2426 $guard = $rsrc->schema->storage->txn_scope_guard
2427 if $slices_with_rels;
2429 ### main source data
2430 # FIXME - need to switch entirely to a coderef-based thing,
2431 # so that large sets aren't copied several times... I think
2432 $rsrc->storage->insert_bulk(
2434 [ @$colnames, sort keys %$rs_data ],
2436 ref $data->[$_] eq 'ARRAY'
2438 $slices_with_rels ? [ @{$data->[$_]}[0..$#$colnames], @{$rs_data_vals||[]} ] # the collist changed
2439 : $rs_data_vals ? [ @{$data->[$_]}, @$rs_data_vals ]
2442 : [ @{$data->[$_]}{@$colnames}, @{$rs_data_vals||[]} ]
2443 } $data_start .. $#$data ],
2446 ### do the children relationships
2447 if ( $slices_with_rels ) {
2448 my @rels = grep { $colinfo->{$_}{is_rel} } keys %$colinfo
2449 or die 'wtf... please report a bug with DBIC_TRACE=1 output (stacktrace)';
2451 for my $sl (@$slices_with_rels) {
2453 my ($main_proto, $main_proto_rs);
2454 for my $rel (@rels) {
2455 next unless defined $sl->{$rel};
2459 (map { $_ => $sl->{$_} } @$colnames),
2462 unless (defined $colinfo->{$rel}{rs}) {
2464 $colinfo->{$rel}{rs} = $rsrc->related_source($rel)->resultset;
2466 $colinfo->{$rel}{fk_map} = { reverse %{ $rsrc->_resolve_relationship_condition(
2468 self_alias => "\xFE", # irrelevant
2469 foreign_alias => "\xFF", # irrelevant
2470 )->{identity_map} || {} } };
2474 $colinfo->{$rel}{rs}->search({ map # only so that we inherit them values properly, no actual search
2477 ( $main_proto_rs ||= $rsrc->resultset->search($main_proto) )
2478 ->get_column( $colinfo->{$rel}{fk_map}{$_} )
2482 keys %{$colinfo->{$rel}{fk_map}}
2483 })->populate( ref $sl->{$rel} eq 'ARRAY' ? $sl->{$rel} : [ $sl->{$rel} ] );
2490 $guard->commit if $guard;
2497 =item Arguments: none
2499 =item Return Value: L<$pager|Data::Page>
2503 Returns a L<Data::Page> object for the current resultset. Only makes
2504 sense for queries with a C<page> attribute.
2506 To get the full count of entries for a paged resultset, call
2507 C<total_entries> on the L<Data::Page> object.
2514 return $self->{pager} if $self->{pager};
2516 my $attrs = $self->{attrs};
2517 if (!defined $attrs->{page}) {
2518 $self->throw_exception("Can't create pager for non-paged rs");
2520 elsif ($attrs->{page} <= 0) {
2521 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2523 $attrs->{rows} ||= 10;
2525 # throw away the paging flags and re-run the count (possibly
2526 # with a subselect) to get the real total count
2527 my $count_attrs = { %$attrs };
2528 delete @{$count_attrs}{qw/rows offset page pager/};
2530 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2532 require DBIx::Class::ResultSet::Pager;
2533 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2534 sub { $total_rs->count }, #lazy-get the total
2536 $self->{attrs}{page},
2544 =item Arguments: $page_number
2546 =item Return Value: L<$resultset|/search>
2550 Returns a resultset for the $page_number page of the resultset on which page
2551 is called, where each page contains a number of rows equal to the 'rows'
2552 attribute set on the resultset (10 by default).
2557 my ($self, $page) = @_;
2558 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2565 =item Arguments: \%col_data
2567 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2571 Creates a new result object in the resultset's result class and returns
2572 it. The row is not inserted into the database at this point, call
2573 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2574 will tell you whether the result object has been inserted or not.
2576 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2581 my ($self, $values) = @_;
2583 $self->throw_exception( "new_result takes only one argument - a hashref of values" )
2586 $self->throw_exception( "Result object instantiation requires a hashref as argument" )
2587 unless (ref $values eq 'HASH');
2589 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2591 my $new = $self->result_class->new({
2593 ( @$cols_from_relations
2594 ? (-cols_from_relations => $cols_from_relations)
2597 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2601 reftype($new) eq 'HASH'
2607 carp_unique (sprintf (
2608 "%s->new returned a blessed empty hashref - a strong indicator something is wrong with its inheritance chain",
2609 $self->result_class,
2616 # _merge_with_rscond
2618 # Takes a simple hash of K/V data and returns its copy merged with the
2619 # condition already present on the resultset. Additionally returns an
2620 # arrayref of value/condition names, which were inferred from related
2621 # objects (this is needed for in-memory related objects)
2622 sub _merge_with_rscond {
2623 my ($self, $data) = @_;
2625 my ($implied_data, @cols_from_relations);
2627 my $alias = $self->{attrs}{alias};
2629 if (! defined $self->{cond}) {
2630 # just massage $data below
2632 elsif ($self->{cond} eq UNRESOLVABLE_CONDITION) {
2633 $implied_data = $self->{attrs}{related_objects}; # nothing might have been inserted yet
2634 @cols_from_relations = keys %{ $implied_data || {} };
2637 my $eqs = $self->result_source->schema->storage->_extract_fixed_condition_columns($self->{cond}, 'consider_nulls');
2638 $implied_data = { map {
2639 ( ($eqs->{$_}||'') eq UNRESOLVABLE_CONDITION ) ? () : ( $_ => $eqs->{$_} )
2645 { %{ $self->_remove_alias($_, $alias) } }
2646 # precedence must be given to passed values over values inherited from
2647 # the cond, so the order here is important.
2648 ( $implied_data||(), $data)
2650 \@cols_from_relations
2654 # _has_resolved_attr
2656 # determines if the resultset defines at least one
2657 # of the attributes supplied
2659 # used to determine if a subquery is necessary
2661 # supports some virtual attributes:
2663 # This will scan for any joins being present on the resultset.
2664 # It is not a mere key-search but a deep inspection of {from}
2667 sub _has_resolved_attr {
2668 my ($self, @attr_names) = @_;
2670 my $attrs = $self->_resolved_attrs;
2674 for my $n (@attr_names) {
2675 if (grep { $n eq $_ } (qw/-join/) ) {
2676 $extra_checks{$n}++;
2680 my $attr = $attrs->{$n};
2682 next if not defined $attr;
2684 if (ref $attr eq 'HASH') {
2685 return 1 if keys %$attr;
2687 elsif (ref $attr eq 'ARRAY') {
2695 # a resolved join is expressed as a multi-level from
2697 $extra_checks{-join}
2699 ref $attrs->{from} eq 'ARRAY'
2701 @{$attrs->{from}} > 1
2709 # Remove the specified alias from the specified query hash. A copy is made so
2710 # the original query is not modified.
2713 my ($self, $query, $alias) = @_;
2715 my %orig = %{ $query || {} };
2718 foreach my $key (keys %orig) {
2720 $unaliased{$key} = $orig{$key};
2723 $unaliased{$1} = $orig{$key}
2724 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2734 =item Arguments: none
2736 =item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
2740 Returns the SQL query and bind vars associated with the invocant.
2742 This is generally used as the RHS for a subquery.
2749 my $attrs = { %{ $self->_resolved_attrs } };
2751 my $aq = $self->result_source->storage->_select_args_to_query (
2752 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
2762 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2764 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2768 my $artist = $schema->resultset('Artist')->find_or_new(
2769 { artist => 'fred' }, { key => 'artists' });
2771 $cd->cd_to_producer->find_or_new({ producer => $producer },
2772 { key => 'primary' });
2774 Find an existing record from this resultset using L</find>. if none exists,
2775 instantiate a new result object and return it. The object will not be saved
2776 into your storage until you call L<DBIx::Class::Row/insert> on it.
2778 You most likely want this method when looking for existing rows using a unique
2779 constraint that is not the primary key, or looking for related rows.
2781 If you want objects to be saved immediately, use L</find_or_create> instead.
2783 B<Note>: Make sure to read the documentation of L</find> and understand the
2784 significance of the C<key> attribute, as its lack may skew your search, and
2785 subsequently result in spurious new objects.
2787 B<Note>: Take care when using C<find_or_new> with a table having
2788 columns with default values that you intend to be automatically
2789 supplied by the database (e.g. an auto_increment primary key column).
2790 In normal usage, the value of such columns should NOT be included at
2791 all in the call to C<find_or_new>, even when set to C<undef>.
2797 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2798 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2799 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2802 return $self->new_result($hash);
2809 =item Arguments: \%col_data
2811 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2815 Attempt to create a single new row or a row with multiple related rows
2816 in the table represented by the resultset (and related tables). This
2817 will not check for duplicate rows before inserting, use
2818 L</find_or_create> to do that.
2820 To create one row for this resultset, pass a hashref of key/value
2821 pairs representing the columns of the table and the values you wish to
2822 store. If the appropriate relationships are set up, foreign key fields
2823 can also be passed an object representing the foreign row, and the
2824 value will be set to its primary key.
2826 To create related objects, pass a hashref of related-object column values
2827 B<keyed on the relationship name>. If the relationship is of type C<multi>
2828 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2829 The process will correctly identify columns holding foreign keys, and will
2830 transparently populate them from the keys of the corresponding relation.
2831 This can be applied recursively, and will work correctly for a structure
2832 with an arbitrary depth and width, as long as the relationships actually
2833 exists and the correct column data has been supplied.
2835 Instead of hashrefs of plain related data (key/value pairs), you may
2836 also pass new or inserted objects. New objects (not inserted yet, see
2837 L</new_result>), will be inserted into their appropriate tables.
2839 Effectively a shortcut for C<< ->new_result(\%col_data)->insert >>.
2841 Example of creating a new row.
2843 $person_rs->create({
2844 name=>"Some Person",
2845 email=>"somebody@someplace.com"
2848 Example of creating a new row and also creating rows in a related C<has_many>
2849 or C<has_one> resultset. Note Arrayref.
2852 { artistid => 4, name => 'Manufactured Crap', cds => [
2853 { title => 'My First CD', year => 2006 },
2854 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2859 Example of creating a new row and also creating a row in a related
2860 C<belongs_to> resultset. Note Hashref.
2863 title=>"Music for Silly Walks",
2866 name=>"Silly Musician",
2874 When subclassing ResultSet never attempt to override this method. Since
2875 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2876 lot of the internals simply never call it, so your override will be
2877 bypassed more often than not. Override either L<DBIx::Class::Row/new>
2878 or L<DBIx::Class::Row/insert> depending on how early in the
2879 L</create> process you need to intervene. See also warning pertaining to
2887 #my ($self, $col_data) = @_;
2888 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
2889 return shift->new_result(shift)->insert;
2892 =head2 find_or_create
2896 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2898 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2902 $cd->cd_to_producer->find_or_create({ producer => $producer },
2903 { key => 'primary' });
2905 Tries to find a record based on its primary key or unique constraints; if none
2906 is found, creates one and returns that instead.
2908 my $cd = $schema->resultset('CD')->find_or_create({
2910 artist => 'Massive Attack',
2911 title => 'Mezzanine',
2915 Also takes an optional C<key> attribute, to search by a specific key or unique
2916 constraint. For example:
2918 my $cd = $schema->resultset('CD')->find_or_create(
2920 artist => 'Massive Attack',
2921 title => 'Mezzanine',
2923 { key => 'cd_artist_title' }
2926 B<Note>: Make sure to read the documentation of L</find> and understand the
2927 significance of the C<key> attribute, as its lack may skew your search, and
2928 subsequently result in spurious row creation.
2930 B<Note>: Because find_or_create() reads from the database and then
2931 possibly inserts based on the result, this method is subject to a race
2932 condition. Another process could create a record in the table after
2933 the find has completed and before the create has started. To avoid
2934 this problem, use find_or_create() inside a transaction.
2936 B<Note>: Take care when using C<find_or_create> with a table having
2937 columns with default values that you intend to be automatically
2938 supplied by the database (e.g. an auto_increment primary key column).
2939 In normal usage, the value of such columns should NOT be included at
2940 all in the call to C<find_or_create>, even when set to C<undef>.
2942 See also L</find> and L</update_or_create>. For information on how to declare
2943 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2945 If you need to know if an existing row was found or a new one created use
2946 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2947 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2950 my $cd = $schema->resultset('CD')->find_or_new({
2952 artist => 'Massive Attack',
2953 title => 'Mezzanine',
2957 if( !$cd->in_storage ) {
2964 sub find_or_create {
2966 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2967 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2968 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2971 return $self->new_result($hash)->insert;
2974 =head2 update_or_create
2978 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2980 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2984 $resultset->update_or_create({ col => $val, ... });
2986 Like L</find_or_create>, but if a row is found it is immediately updated via
2987 C<< $found_row->update (\%col_data) >>.
2990 Takes an optional C<key> attribute to search on a specific unique constraint.
2993 # In your application
2994 my $cd = $schema->resultset('CD')->update_or_create(
2996 artist => 'Massive Attack',
2997 title => 'Mezzanine',
3000 { key => 'cd_artist_title' }
3003 $cd->cd_to_producer->update_or_create({
3004 producer => $producer,
3010 B<Note>: Make sure to read the documentation of L</find> and understand the
3011 significance of the C<key> attribute, as its lack may skew your search, and
3012 subsequently result in spurious row creation.
3014 B<Note>: Take care when using C<update_or_create> with a table having
3015 columns with default values that you intend to be automatically
3016 supplied by the database (e.g. an auto_increment primary key column).
3017 In normal usage, the value of such columns should NOT be included at
3018 all in the call to C<update_or_create>, even when set to C<undef>.
3020 See also L</find> and L</find_or_create>. For information on how to declare
3021 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
3023 If you need to know if an existing row was updated or a new one created use
3024 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
3025 to call L<DBIx::Class::Row/insert> to save the newly created row to the
3030 sub update_or_create {
3032 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
3033 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3035 my $row = $self->find($cond, $attrs);
3037 $row->update($cond);
3041 return $self->new_result($cond)->insert;
3044 =head2 update_or_new
3048 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
3050 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
3054 $resultset->update_or_new({ col => $val, ... });
3056 Like L</find_or_new> but if a row is found it is immediately updated via
3057 C<< $found_row->update (\%col_data) >>.
3061 # In your application
3062 my $cd = $schema->resultset('CD')->update_or_new(
3064 artist => 'Massive Attack',
3065 title => 'Mezzanine',
3068 { key => 'cd_artist_title' }
3071 if ($cd->in_storage) {
3072 # the cd was updated
3075 # the cd is not yet in the database, let's insert it
3079 B<Note>: Make sure to read the documentation of L</find> and understand the
3080 significance of the C<key> attribute, as its lack may skew your search, and
3081 subsequently result in spurious new objects.
3083 B<Note>: Take care when using C<update_or_new> with a table having
3084 columns with default values that you intend to be automatically
3085 supplied by the database (e.g. an auto_increment primary key column).
3086 In normal usage, the value of such columns should NOT be included at
3087 all in the call to C<update_or_new>, even when set to C<undef>.
3089 See also L</find>, L</find_or_create> and L</find_or_new>.
3095 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
3096 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3098 my $row = $self->find( $cond, $attrs );
3099 if ( defined $row ) {
3100 $row->update($cond);
3104 return $self->new_result($cond);
3111 =item Arguments: none
3113 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass> | undef
3117 Gets the contents of the cache for the resultset, if the cache is set.
3119 The cache is populated either by using the L</prefetch> attribute to
3120 L</search> or by calling L</set_cache>.
3132 =item Arguments: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3134 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3138 Sets the contents of the cache for the resultset. Expects an arrayref
3139 of objects of the same class as those produced by the resultset. Note that
3140 if the cache is set, the resultset will return the cached objects rather
3141 than re-querying the database even if the cache attr is not set.
3143 The contents of the cache can also be populated by using the
3144 L</prefetch> attribute to L</search>.
3149 my ( $self, $data ) = @_;
3150 $self->throw_exception("set_cache requires an arrayref")
3151 if defined($data) && (ref $data ne 'ARRAY');
3152 $self->{all_cache} = $data;
3159 =item Arguments: none
3161 =item Return Value: undef
3165 Clears the cache for the resultset.
3170 shift->set_cache(undef);
3177 =item Arguments: none
3179 =item Return Value: true, if the resultset has been paginated
3187 return !!$self->{attrs}{page};
3194 =item Arguments: none
3196 =item Return Value: true, if the resultset has been ordered with C<order_by>.
3204 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
3207 =head2 related_resultset
3211 =item Arguments: $rel_name
3213 =item Return Value: L<$resultset|/search>
3217 Returns a related resultset for the supplied relationship name.
3219 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
3223 sub related_resultset {
3224 my ($self, $rel) = @_;
3226 return $self->{related_resultsets}{$rel}
3227 if defined $self->{related_resultsets}{$rel};
3229 return $self->{related_resultsets}{$rel} = do {
3230 my $rsrc = $self->result_source;
3231 my $rel_info = $rsrc->relationship_info($rel);
3233 $self->throw_exception(
3234 "search_related: result source '" . $rsrc->source_name .
3235 "' has no such relationship $rel")
3238 my $attrs = $self->_chain_relationship($rel);
3240 my $join_count = $attrs->{seen_join}{$rel};
3242 my $alias = $self->result_source->storage
3243 ->relname_to_table_alias($rel, $join_count);
3245 # since this is search_related, and we already slid the select window inwards
3246 # (the select/as attrs were deleted in the beginning), we need to flip all
3247 # left joins to inner, so we get the expected results
3248 # read the comment on top of the actual function to see what this does
3249 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
3252 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3253 delete @{$attrs}{qw(result_class alias)};
3255 my $rel_source = $rsrc->related_source($rel);
3259 # The reason we do this now instead of passing the alias to the
3260 # search_rs below is that if you wrap/overload resultset on the
3261 # source you need to know what alias it's -going- to have for things
3262 # to work sanely (e.g. RestrictWithObject wants to be able to add
3263 # extra query restrictions, and these may need to be $alias.)
3265 my $rel_attrs = $rel_source->resultset_attributes;
3266 local $rel_attrs->{alias} = $alias;
3268 $rel_source->resultset
3272 where => $attrs->{where},
3276 if (my $cache = $self->get_cache) {
3277 my @related_cache = map
3278 { $_->related_resultset($rel)->get_cache || () }
3282 $new->set_cache([ map @$_, @related_cache ]) if @related_cache == @$cache;
3289 =head2 current_source_alias
3293 =item Arguments: none
3295 =item Return Value: $source_alias
3299 Returns the current table alias for the result source this resultset is built
3300 on, that will be used in the SQL query. Usually it is C<me>.
3302 Currently the source alias that refers to the result set returned by a
3303 L</search>/L</find> family method depends on how you got to the resultset: it's
3304 C<me> by default, but eg. L</search_related> aliases it to the related result
3305 source name (and keeps C<me> referring to the original result set). The long
3306 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3307 (and make this method unnecessary).
3309 Thus it's currently necessary to use this method in predefined queries (see
3310 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3311 source alias of the current result set:
3313 # in a result set class
3315 my ($self, $user) = @_;
3317 my $me = $self->current_source_alias;
3319 return $self->search({
3320 "$me.modified" => $user->id,
3326 sub current_source_alias {
3327 return (shift->{attrs} || {})->{alias} || 'me';
3330 =head2 as_subselect_rs
3334 =item Arguments: none
3336 =item Return Value: L<$resultset|/search>
3340 Act as a barrier to SQL symbols. The resultset provided will be made into a
3341 "virtual view" by including it as a subquery within the from clause. From this
3342 point on, any joined tables are inaccessible to ->search on the resultset (as if
3343 it were simply where-filtered without joins). For example:
3345 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3347 # 'x' now pollutes the query namespace
3349 # So the following works as expected
3350 my $ok_rs = $rs->search({'x.other' => 1});
3352 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3353 # def) we look for one row with contradictory terms and join in another table
3354 # (aliased 'x_2') which we never use
3355 my $broken_rs = $rs->search({'x.name' => 'def'});
3357 my $rs2 = $rs->as_subselect_rs;
3359 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3360 my $not_joined_rs = $rs2->search({'x.other' => 1});
3362 # works as expected: finds a 'table' row related to two x rows (abc and def)
3363 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3365 Another example of when one might use this would be to select a subset of
3366 columns in a group by clause:
3368 my $rs = $schema->resultset('Bar')->search(undef, {
3369 group_by => [qw{ id foo_id baz_id }],
3370 })->as_subselect_rs->search(undef, {
3371 columns => [qw{ id foo_id }]
3374 In the above example normally columns would have to be equal to the group by,
3375 but because we isolated the group by into a subselect the above works.
3379 sub as_subselect_rs {
3382 my $attrs = $self->_resolved_attrs;
3384 my $fresh_rs = (ref $self)->new (
3385 $self->result_source
3388 # these pieces will be locked in the subquery
3389 delete $fresh_rs->{cond};
3390 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3392 return $fresh_rs->search( {}, {
3394 $attrs->{alias} => $self->as_query,
3395 -alias => $attrs->{alias},
3396 -rsrc => $self->result_source,
3398 alias => $attrs->{alias},
3402 # This code is called by search_related, and makes sure there
3403 # is clear separation between the joins before, during, and
3404 # after the relationship. This information is needed later
3405 # in order to properly resolve prefetch aliases (any alias
3406 # with a relation_chain_depth less than the depth of the
3407 # current prefetch is not considered)
3409 # The increments happen twice per join. An even number means a
3410 # relationship specified via a search_related, whereas an odd
3411 # number indicates a join/prefetch added via attributes
3413 # Also this code will wrap the current resultset (the one we
3414 # chain to) in a subselect IFF it contains limiting attributes
3415 sub _chain_relationship {
3416 my ($self, $rel) = @_;
3417 my $source = $self->result_source;
3418 my $attrs = { %{$self->{attrs}||{}} };
3420 # we need to take the prefetch the attrs into account before we
3421 # ->_resolve_join as otherwise they get lost - captainL
3422 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3424 delete @{$attrs}{qw/join prefetch collapse group_by distinct _grouped_by_distinct select as columns +select +as +columns/};
3426 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3429 my @force_subq_attrs = qw/offset rows group_by having/;
3432 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3434 $self->_has_resolved_attr (@force_subq_attrs)
3436 # Nuke the prefetch (if any) before the new $rs attrs
3437 # are resolved (prefetch is useless - we are wrapping
3438 # a subquery anyway).
3439 my $rs_copy = $self->search;
3440 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3441 $rs_copy->{attrs}{join},
3442 delete $rs_copy->{attrs}{prefetch},
3447 -alias => $attrs->{alias},
3448 $attrs->{alias} => $rs_copy->as_query,
3450 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3451 $seen->{-relation_chain_depth} = 0;
3453 elsif ($attrs->{from}) { #shallow copy suffices
3454 $from = [ @{$attrs->{from}} ];
3459 -alias => $attrs->{alias},
3460 $attrs->{alias} => $source->from,
3464 my $jpath = ($seen->{-relation_chain_depth})
3465 ? $from->[-1][0]{-join_path}
3468 my @requested_joins = $source->_resolve_join(
3475 push @$from, @requested_joins;
3477 $seen->{-relation_chain_depth}++;
3479 # if $self already had a join/prefetch specified on it, the requested
3480 # $rel might very well be already included. What we do in this case
3481 # is effectively a no-op (except that we bump up the chain_depth on
3482 # the join in question so we could tell it *is* the search_related)
3485 # we consider the last one thus reverse
3486 for my $j (reverse @requested_joins) {
3487 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3488 if ($rel eq $last_j) {
3489 $j->[0]{-relation_chain_depth}++;
3495 unless ($already_joined) {
3496 push @$from, $source->_resolve_join(
3504 $seen->{-relation_chain_depth}++;
3506 return {%$attrs, from => $from, seen_join => $seen};
3509 sub _resolved_attrs {
3511 return $self->{_attrs} if $self->{_attrs};
3513 my $attrs = { %{ $self->{attrs} || {} } };
3514 my $source = $attrs->{result_source} = $self->result_source;
3515 my $alias = $attrs->{alias};
3517 $self->throw_exception("Specifying distinct => 1 in conjunction with collapse => 1 is unsupported")
3518 if $attrs->{collapse} and $attrs->{distinct};
3520 # default selection list
3521 $attrs->{columns} = [ $source->columns ]
3522 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3524 # merge selectors together
3525 for (qw/columns select as/) {
3526 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3527 if $attrs->{$_} or $attrs->{"+$_"};
3530 # disassemble columns
3532 if (my $cols = delete $attrs->{columns}) {
3533 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3534 if (ref $c eq 'HASH') {
3535 for my $as (sort keys %$c) {
3536 push @sel, $c->{$as};
3547 # when trying to weed off duplicates later do not go past this point -
3548 # everything added from here on is unbalanced "anyone's guess" stuff
3549 my $dedup_stop_idx = $#as;
3551 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3553 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3554 if $attrs->{select};
3556 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3557 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3559 # disqualify all $alias.col as-bits (inflate-map mandated)
3560 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3562 # de-duplicate the result (remove *identical* select/as pairs)
3563 # and also die on duplicate {as} pointing to different {select}s
3564 # not using a c-style for as the condition is prone to shrinkage
3567 while ($i <= $dedup_stop_idx) {
3568 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3573 elsif ($seen->{$as[$i]}++) {
3574 $self->throw_exception(
3575 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3583 $attrs->{select} = \@sel;
3584 $attrs->{as} = \@as;
3586 $attrs->{from} ||= [{
3588 -alias => $self->{attrs}{alias},
3589 $self->{attrs}{alias} => $source->from,
3592 if ( $attrs->{join} || $attrs->{prefetch} ) {
3594 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3595 if ref $attrs->{from} ne 'ARRAY';
3597 my $join = (delete $attrs->{join}) || {};
3599 if ( defined $attrs->{prefetch} ) {
3600 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3603 $attrs->{from} = # have to copy here to avoid corrupting the original
3605 @{ $attrs->{from} },
3606 $source->_resolve_join(
3609 { %{ $attrs->{seen_join} || {} } },
3610 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3611 ? $attrs->{from}[-1][0]{-join_path}
3618 if ( defined $attrs->{order_by} ) {
3619 $attrs->{order_by} = (
3620 ref( $attrs->{order_by} ) eq 'ARRAY'
3621 ? [ @{ $attrs->{order_by} } ]
3622 : [ $attrs->{order_by} || () ]
3626 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3627 $attrs->{group_by} = [ $attrs->{group_by} ];
3631 # generate selections based on the prefetch helper
3632 my ($prefetch, @prefetch_select, @prefetch_as);
3633 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3634 if defined $attrs->{prefetch};
3638 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3639 if $attrs->{_dark_selector};
3641 $self->throw_exception("Specifying prefetch in conjunction with an explicit collapse => 0 is unsupported")
3642 if defined $attrs->{collapse} and ! $attrs->{collapse};
3644 $attrs->{collapse} = 1;
3646 # this is a separate structure (we don't look in {from} directly)
3647 # as the resolver needs to shift things off the lists to work
3648 # properly (identical-prefetches on different branches)
3650 if (ref $attrs->{from} eq 'ARRAY') {
3652 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3654 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3655 next unless $j->[0]{-alias};
3656 next unless $j->[0]{-join_path};
3657 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3659 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3662 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3663 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3667 my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map );
3669 # save these for after distinct resolution
3670 @prefetch_select = map { $_->[0] } @prefetch;
3671 @prefetch_as = map { $_->[1] } @prefetch;
3674 # run through the resulting joinstructure (starting from our current slot)
3675 # and unset collapse if proven unnecessary
3677 # also while we are at it find out if the current root source has
3678 # been premultiplied by previous related_source chaining
3680 # this allows to predict whether a root object with all other relation
3681 # data set to NULL is in fact unique
3682 if ($attrs->{collapse}) {
3684 if (ref $attrs->{from} eq 'ARRAY') {
3686 if (@{$attrs->{from}} == 1) {
3687 # no joins - no collapse
3688 $attrs->{collapse} = 0;
3691 # find where our table-spec starts
3692 my @fromlist = @{$attrs->{from}};
3694 my $t = shift @fromlist;
3697 # me vs join from-spec distinction - a ref means non-root
3698 if (ref $t eq 'ARRAY') {
3700 $is_multi ||= ! $t->{-is_single};
3702 last if ($t->{-alias} && $t->{-alias} eq $alias);
3703 $attrs->{_main_source_premultiplied} ||= $is_multi;
3706 # no non-singles remaining, nor any premultiplication - nothing to collapse
3708 ! $attrs->{_main_source_premultiplied}
3710 ! List::Util::first { ! $_->[0]{-is_single} } @fromlist
3712 $attrs->{collapse} = 0;
3718 # if we can not analyze the from - err on the side of safety
3719 $attrs->{_main_source_premultiplied} = 1;
3723 # generate the distinct induced group_by before injecting the prefetched select/as parts
3724 if (delete $attrs->{distinct}) {
3725 if ($attrs->{group_by}) {
3726 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3729 $attrs->{_grouped_by_distinct} = 1;
3730 # distinct affects only the main selection part, not what prefetch may add below
3731 ($attrs->{group_by}, my $new_order) = $source->storage->_group_over_selection($attrs);
3733 # FIXME possibly ignore a rewritten order_by (may turn out to be an issue)
3734 # The thinking is: if we are collapsing the subquerying prefetch engine will
3735 # rip stuff apart for us anyway, and we do not want to have a potentially
3736 # function-converted external order_by
3737 # ( there is an explicit if ( collapse && _grouped_by_distinct ) check in DBIHacks )
3738 $attrs->{order_by} = $new_order unless $attrs->{collapse};
3742 # inject prefetch-bound selection (if any)
3743 push @{$attrs->{select}}, @prefetch_select;
3744 push @{$attrs->{as}}, @prefetch_as;
3746 $attrs->{_simple_passthrough_construction} = !(
3749 grep { $_ =~ /\./ } @{$attrs->{as}}
3752 # if both page and offset are specified, produce a combined offset
3753 # even though it doesn't make much sense, this is what pre 081xx has
3755 if (my $page = delete $attrs->{page}) {
3757 ($attrs->{rows} * ($page - 1))
3759 ($attrs->{offset} || 0)
3763 return $self->{_attrs} = $attrs;
3767 my ($self, $attr) = @_;
3769 if (ref $attr eq 'HASH') {
3770 return $self->_rollout_hash($attr);
3771 } elsif (ref $attr eq 'ARRAY') {
3772 return $self->_rollout_array($attr);
3778 sub _rollout_array {
3779 my ($self, $attr) = @_;
3782 foreach my $element (@{$attr}) {
3783 if (ref $element eq 'HASH') {
3784 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3785 } elsif (ref $element eq 'ARRAY') {
3786 # XXX - should probably recurse here
3787 push( @rolled_array, @{$self->_rollout_array($element)} );
3789 push( @rolled_array, $element );
3792 return \@rolled_array;
3796 my ($self, $attr) = @_;
3799 foreach my $key (keys %{$attr}) {
3800 push( @rolled_array, { $key => $attr->{$key} } );
3802 return \@rolled_array;
3805 sub _calculate_score {
3806 my ($self, $a, $b) = @_;
3808 if (defined $a xor defined $b) {
3811 elsif (not defined $a) {
3815 if (ref $b eq 'HASH') {
3816 my ($b_key) = keys %{$b};
3817 if (ref $a eq 'HASH') {
3818 my ($a_key) = keys %{$a};
3819 if ($a_key eq $b_key) {
3820 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3825 return ($a eq $b_key) ? 1 : 0;
3828 if (ref $a eq 'HASH') {
3829 my ($a_key) = keys %{$a};
3830 return ($b eq $a_key) ? 1 : 0;
3832 return ($b eq $a) ? 1 : 0;
3837 sub _merge_joinpref_attr {
3838 my ($self, $orig, $import) = @_;
3840 return $import unless defined($orig);
3841 return $orig unless defined($import);
3843 $orig = $self->_rollout_attr($orig);
3844 $import = $self->_rollout_attr($import);
3847 foreach my $import_element ( @{$import} ) {
3848 # find best candidate from $orig to merge $b_element into
3849 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3850 foreach my $orig_element ( @{$orig} ) {
3851 my $score = $self->_calculate_score( $orig_element, $import_element );
3852 if ($score > $best_candidate->{score}) {
3853 $best_candidate->{position} = $position;
3854 $best_candidate->{score} = $score;
3858 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3859 $import_key = '' if not defined $import_key;
3861 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3862 push( @{$orig}, $import_element );
3864 my $orig_best = $orig->[$best_candidate->{position}];
3865 # merge orig_best and b_element together and replace original with merged
3866 if (ref $orig_best ne 'HASH') {
3867 $orig->[$best_candidate->{position}] = $import_element;
3868 } elsif (ref $import_element eq 'HASH') {
3869 my ($key) = keys %{$orig_best};
3870 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3873 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3876 return @$orig ? $orig : ();
3884 require Hash::Merge;
3885 my $hm = Hash::Merge->new;
3887 $hm->specify_behavior({
3890 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3892 if ($defl xor $defr) {
3893 return [ $defl ? $_[0] : $_[1] ];
3898 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3902 return [$_[0], $_[1]];
3906 return $_[1] if !defined $_[0];
3907 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3908 return [$_[0], @{$_[1]}]
3911 return [] if !defined $_[0] and !keys %{$_[1]};
3912 return [ $_[1] ] if !defined $_[0];
3913 return [ $_[0] ] if !keys %{$_[1]};
3914 return [$_[0], $_[1]]
3919 return $_[0] if !defined $_[1];
3920 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3921 return [@{$_[0]}, $_[1]]
3924 my @ret = @{$_[0]} or return $_[1];
3925 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3926 my %idx = map { $_ => 1 } @ret;
3927 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3931 return [ $_[1] ] if ! @{$_[0]};
3932 return $_[0] if !keys %{$_[1]};
3933 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3934 return [ @{$_[0]}, $_[1] ];
3939 return [] if !keys %{$_[0]} and !defined $_[1];
3940 return [ $_[0] ] if !defined $_[1];
3941 return [ $_[1] ] if !keys %{$_[0]};
3942 return [$_[0], $_[1]]
3945 return [] if !keys %{$_[0]} and !@{$_[1]};
3946 return [ $_[0] ] if !@{$_[1]};
3947 return $_[1] if !keys %{$_[0]};
3948 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3949 return [ $_[0], @{$_[1]} ];
3952 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3953 return [ $_[0] ] if !keys %{$_[1]};
3954 return [ $_[1] ] if !keys %{$_[0]};
3955 return [ $_[0] ] if $_[0] eq $_[1];
3956 return [ $_[0], $_[1] ];
3959 } => 'DBIC_RS_ATTR_MERGER');
3963 return $hm->merge ($_[1], $_[2]);
3967 sub STORABLE_freeze {
3968 my ($self, $cloning) = @_;
3969 my $to_serialize = { %$self };
3971 # A cursor in progress can't be serialized (and would make little sense anyway)
3972 # the parser can be regenerated (and can't be serialized)
3973 delete @{$to_serialize}{qw/cursor _row_parser _result_inflator/};
3975 # nor is it sensical to store a not-yet-fired-count pager
3976 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3977 delete $to_serialize->{pager};
3980 Storable::nfreeze($to_serialize);
3983 # need this hook for symmetry
3985 my ($self, $cloning, $serialized) = @_;
3987 %$self = %{ Storable::thaw($serialized) };
3993 =head2 throw_exception
3995 See L<DBIx::Class::Schema/throw_exception> for details.
3999 sub throw_exception {
4002 if (ref $self and my $rsrc = $self->result_source) {
4003 $rsrc->throw_exception(@_)
4006 DBIx::Class::Exception->throw(@_);
4014 # XXX: FIXME: Attributes docs need clearing up
4018 Attributes are used to refine a ResultSet in various ways when
4019 searching for data. They can be passed to any method which takes an
4020 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
4023 Default attributes can be set on the result class using
4024 L<DBIx::Class::ResultSource/resultset_attributes>. (Please read
4025 the CAVEATS on that feature before using it!)
4027 These are in no particular order:
4033 =item Value: ( $order_by | \@order_by | \%order_by )
4037 Which column(s) to order the results by.
4039 [The full list of suitable values is documented in
4040 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
4043 If a single column name, or an arrayref of names is supplied, the
4044 argument is passed through directly to SQL. The hashref syntax allows
4045 for connection-agnostic specification of ordering direction:
4047 For descending order:
4049 order_by => { -desc => [qw/col1 col2 col3/] }
4051 For explicit ascending order:
4053 order_by => { -asc => 'col' }
4055 The old scalarref syntax (i.e. order_by => \'year DESC') is still
4056 supported, although you are strongly encouraged to use the hashref
4057 syntax as outlined above.
4063 =item Value: \@columns | \%columns | $column
4067 Shortcut to request a particular set of columns to be retrieved. Each
4068 column spec may be a string (a table column name), or a hash (in which
4069 case the key is the C<as> value, and the value is used as the C<select>
4070 expression). Adds the L</current_source_alias> onto the start of any column without a C<.> in
4071 it and sets C<select> from that, then auto-populates C<as> from
4072 C<select> as normal. (You may also use the C<cols> attribute, as in
4073 earlier versions of DBIC, but this is deprecated)
4075 Essentially C<columns> does the same as L</select> and L</as>.
4077 columns => [ 'some_column', { dbic_slot => 'another_column' } ]
4081 select => [qw(some_column another_column)],
4082 as => [qw(some_column dbic_slot)]
4084 If you want to individually retrieve related columns (in essence perform
4085 manual prefetch) you have to make sure to specify the correct inflation slot
4086 chain such that it matches existing relationships:
4088 my $rs = $schema->resultset('Artist')->search({}, {
4089 # required to tell DBIC to collapse has_many relationships
4091 join => { cds => 'tracks'},
4093 'cds.cdid' => 'cds.cdid',
4094 'cds.tracks.title' => 'tracks.title',
4100 B<NOTE:> You B<MUST> explicitly quote C<'+columns'> when using this attribute.
4101 Not doing so causes Perl to incorrectly interpret C<+columns> as a bareword
4102 with a unary plus operator before it, which is the same as simply C<columns>.
4106 =item Value: \@extra_columns
4110 Indicates additional columns to be selected from storage. Works the same as
4111 L</columns> but adds columns to the current selection. (You may also use the
4112 C<include_columns> attribute, as in earlier versions of DBIC, but this is
4115 $schema->resultset('CD')->search(undef, {
4116 '+columns' => ['artist.name'],
4120 would return all CDs and include a 'name' column to the information
4121 passed to object inflation. Note that the 'artist' is the name of the
4122 column (or relationship) accessor, and 'name' is the name of the column
4123 accessor in the related table.
4129 =item Value: \@select_columns
4133 Indicates which columns should be selected from the storage. You can use
4134 column names, or in the case of RDBMS back ends, function or stored procedure
4137 $rs = $schema->resultset('Employee')->search(undef, {
4140 { count => 'employeeid' },
4141 { max => { length => 'name' }, -as => 'longest_name' }
4146 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
4148 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
4149 use L</select>, to instruct DBIx::Class how to store the result of the column.
4150 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
4151 identifier aliasing. You can however alias a function, so you can use it in
4152 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
4153 attribute> supplied as shown in the example above.
4157 B<NOTE:> You B<MUST> explicitly quote C<'+select'> when using this attribute.
4158 Not doing so causes Perl to incorrectly interpret C<+select> as a bareword
4159 with a unary plus operator before it, which is the same as simply C<select>.
4163 =item Value: \@extra_select_columns
4167 Indicates additional columns to be selected from storage. Works the same as
4168 L</select> but adds columns to the current selection, instead of specifying
4169 a new explicit list.
4175 =item Value: \@inflation_names
4179 Indicates DBIC-side names for object inflation. That is L</as> indicates the
4180 slot name in which the column value will be stored within the
4181 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
4182 identifier by the C<get_column> method (or via the object accessor B<if one
4183 with the same name already exists>) as shown below. The L</as> attribute has
4184 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
4186 $rs = $schema->resultset('Employee')->search(undef, {
4189 { count => 'employeeid' },
4190 { max => { length => 'name' }, -as => 'longest_name' }
4199 If the object against which the search is performed already has an accessor
4200 matching a column name specified in C<as>, the value can be retrieved using
4201 the accessor as normal:
4203 my $name = $employee->name();
4205 If on the other hand an accessor does not exist in the object, you need to
4206 use C<get_column> instead:
4208 my $employee_count = $employee->get_column('employee_count');
4210 You can create your own accessors if required - see
4211 L<DBIx::Class::Manual::Cookbook> for details.
4215 B<NOTE:> You B<MUST> explicitly quote C<'+as'> when using this attribute.
4216 Not doing so causes Perl to incorrectly interpret C<+as> as a bareword
4217 with a unary plus operator before it, which is the same as simply C<as>.
4221 =item Value: \@extra_inflation_names
4225 Indicates additional inflation names for selectors added via L</+select>. See L</as>.
4231 =item Value: ($rel_name | \@rel_names | \%rel_names)
4235 Contains a list of relationships that should be joined for this query. For
4238 # Get CDs by Nine Inch Nails
4239 my $rs = $schema->resultset('CD')->search(
4240 { 'artist.name' => 'Nine Inch Nails' },
4241 { join => 'artist' }
4244 Can also contain a hash reference to refer to the other relation's relations.
4247 package MyApp::Schema::Track;
4248 use base qw/DBIx::Class/;
4249 __PACKAGE__->table('track');
4250 __PACKAGE__->add_columns(qw/trackid cd position title/);
4251 __PACKAGE__->set_primary_key('trackid');
4252 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
4255 # In your application
4256 my $rs = $schema->resultset('Artist')->search(
4257 { 'track.title' => 'Teardrop' },
4259 join => { cd => 'track' },
4260 order_by => 'artist.name',
4264 You need to use the relationship (not the table) name in conditions,
4265 because they are aliased as such. The current table is aliased as "me", so
4266 you need to use me.column_name in order to avoid ambiguity. For example:
4268 # Get CDs from 1984 with a 'Foo' track
4269 my $rs = $schema->resultset('CD')->search(
4272 'tracks.name' => 'Foo'
4274 { join => 'tracks' }
4277 If the same join is supplied twice, it will be aliased to <rel>_2 (and
4278 similarly for a third time). For e.g.
4280 my $rs = $schema->resultset('Artist')->search({
4281 'cds.title' => 'Down to Earth',
4282 'cds_2.title' => 'Popular',
4284 join => [ qw/cds cds/ ],
4287 will return a set of all artists that have both a cd with title 'Down
4288 to Earth' and a cd with title 'Popular'.
4290 If you want to fetch related objects from other tables as well, see L</prefetch>
4293 NOTE: An internal join-chain pruner will discard certain joins while
4294 constructing the actual SQL query, as long as the joins in question do not
4295 affect the retrieved result. This for example includes 1:1 left joins
4296 that are not part of the restriction specification (WHERE/HAVING) nor are
4297 a part of the query selection.
4299 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4305 =item Value: (0 | 1)
4309 When set to a true value, indicates that any rows fetched from joined has_many
4310 relationships are to be aggregated into the corresponding "parent" object. For
4311 example, the resultset:
4313 my $rs = $schema->resultset('CD')->search({}, {
4314 '+columns' => [ qw/ tracks.title tracks.position / ],
4319 While executing the following query:
4321 SELECT me.*, tracks.title, tracks.position
4323 LEFT JOIN track tracks
4324 ON tracks.cdid = me.cdid
4326 Will return only as many objects as there are rows in the CD source, even
4327 though the result of the query may span many rows. Each of these CD objects
4328 will in turn have multiple "Track" objects hidden behind the has_many
4329 generated accessor C<tracks>. Without C<< collapse => 1 >>, the return values
4330 of this resultset would be as many CD objects as there are tracks (a "Cartesian
4331 product"), with each CD object containing exactly one of all fetched Track data.
4333 When a collapse is requested on a non-ordered resultset, an order by some
4334 unique part of the main source (the left-most table) is inserted automatically.
4335 This is done so that the resultset is allowed to be "lazy" - calling
4336 L<< $rs->next|/next >> will fetch only as many rows as it needs to build the next
4337 object with all of its related data.
4339 If an L</order_by> is already declared, and orders the resultset in a way that
4340 makes collapsing as described above impossible (e.g. C<< ORDER BY
4341 has_many_rel.column >> or C<ORDER BY RANDOM()>), DBIC will automatically
4342 switch to "eager" mode and slurp the entire resultset before constructing the
4343 first object returned by L</next>.
4345 Setting this attribute on a resultset that does not join any has_many
4346 relations is a no-op.
4348 For a more in-depth discussion, see L</PREFETCHING>.
4354 =item Value: ($rel_name | \@rel_names | \%rel_names)
4358 This attribute is a shorthand for specifying a L</join> spec, adding all
4359 columns from the joined related sources as L</+columns> and setting
4360 L</collapse> to a true value. For example, the following two queries are
4363 my $rs = $schema->resultset('Artist')->search({}, {
4364 prefetch => { cds => ['genre', 'tracks' ] },
4369 my $rs = $schema->resultset('Artist')->search({}, {
4370 join => { cds => ['genre', 'tracks' ] },
4374 { +{ "cds.$_" => "cds.$_" } }
4375 $schema->source('Artist')->related_source('cds')->columns
4378 { +{ "cds.genre.$_" => "genre.$_" } }
4379 $schema->source('Artist')->related_source('cds')->related_source('genre')->columns
4382 { +{ "cds.tracks.$_" => "tracks.$_" } }
4383 $schema->source('Artist')->related_source('cds')->related_source('tracks')->columns
4388 Both producing the following SQL:
4390 SELECT me.artistid, me.name, me.rank, me.charfield,
4391 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track,
4392 genre.genreid, genre.name,
4393 tracks.trackid, tracks.cd, tracks.position, tracks.title, tracks.last_updated_on, tracks.last_updated_at
4396 ON cds.artist = me.artistid
4397 LEFT JOIN genre genre
4398 ON genre.genreid = cds.genreid
4399 LEFT JOIN track tracks
4400 ON tracks.cd = cds.cdid
4401 ORDER BY me.artistid
4403 While L</prefetch> implies a L</join>, it is ok to mix the two together, as
4404 the arguments are properly merged and generally do the right thing. For
4405 example, you may want to do the following:
4407 my $artists_and_cds_without_genre = $schema->resultset('Artist')->search(
4408 { 'genre.genreid' => undef },
4410 join => { cds => 'genre' },
4415 Which generates the following SQL:
4417 SELECT me.artistid, me.name, me.rank, me.charfield,
4418 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track
4421 ON cds.artist = me.artistid
4422 LEFT JOIN genre genre
4423 ON genre.genreid = cds.genreid
4424 WHERE genre.genreid IS NULL
4425 ORDER BY me.artistid
4427 For a more in-depth discussion, see L</PREFETCHING>.
4433 =item Value: $source_alias
4437 Sets the source alias for the query. Normally, this defaults to C<me>, but
4438 nested search queries (sub-SELECTs) might need specific aliases set to
4439 reference inner queries. For example:
4442 ->related_resultset('CDs')
4443 ->related_resultset('Tracks')
4445 'track.id' => { -ident => 'none_search.id' },
4449 my $ids = $self->search({
4452 alias => 'none_search',
4453 group_by => 'none_search.id',
4454 })->get_column('id')->as_query;
4456 $self->search({ id => { -in => $ids } })
4458 This attribute is directly tied to L</current_source_alias>.
4468 Makes the resultset paged and specifies the page to retrieve. Effectively
4469 identical to creating a non-pages resultset and then calling ->page($page)
4472 If L</rows> attribute is not specified it defaults to 10 rows per page.
4474 When you have a paged resultset, L</count> will only return the number
4475 of rows in the page. To get the total, use the L</pager> and call
4476 C<total_entries> on it.
4486 Specifies the maximum number of rows for direct retrieval or the number of
4487 rows per page if the page attribute or method is used.
4493 =item Value: $offset
4497 Specifies the (zero-based) row number for the first row to be returned, or the
4498 of the first row of the first page if paging is used.
4500 =head2 software_limit
4504 =item Value: (0 | 1)
4508 When combined with L</rows> and/or L</offset> the generated SQL will not
4509 include any limit dialect stanzas. Instead the entire result will be selected
4510 as if no limits were specified, and DBIC will perform the limit locally, by
4511 artificially advancing and finishing the resulting L</cursor>.
4513 This is the recommended way of performing resultset limiting when no sane RDBMS
4514 implementation is available (e.g.
4515 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4516 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4522 =item Value: \@columns
4526 A arrayref of columns to group by. Can include columns of joined tables.
4528 group_by => [qw/ column1 column2 ... /]
4534 =item Value: $condition
4538 HAVING is a select statement attribute that is applied between GROUP BY and
4539 ORDER BY. It is applied to the after the grouping calculations have been
4542 having => { 'count_employee' => { '>=', 100 } }
4544 or with an in-place function in which case literal SQL is required:
4546 having => \[ 'count(employee) >= ?', [ count => 100 ] ]
4552 =item Value: (0 | 1)
4556 Set to 1 to automatically generate a L</group_by> clause based on the selection
4557 (including intelligent handling of L</order_by> contents). Note that the group
4558 criteria calculation takes place over the B<final> selection. This includes
4559 any L</+columns>, L</+select> or L</order_by> additions in subsequent
4560 L</search> calls, and standalone columns selected via
4561 L<DBIx::Class::ResultSetColumn> (L</get_column>). A notable exception are the
4562 extra selections specified via L</prefetch> - such selections are explicitly
4563 excluded from group criteria calculations.
4565 If the final ResultSet also explicitly defines a L</group_by> attribute, this
4566 setting is ignored and an appropriate warning is issued.
4572 Adds to the WHERE clause.
4574 # only return rows WHERE deleted IS NULL for all searches
4575 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4577 Can be overridden by passing C<< { where => undef } >> as an attribute
4580 For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
4586 Set to 1 to cache search results. This prevents extra SQL queries if you
4587 revisit rows in your ResultSet:
4589 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4591 while( my $artist = $resultset->next ) {
4595 $rs->first; # without cache, this would issue a query
4597 By default, searches are not cached.
4599 For more examples of using these attributes, see
4600 L<DBIx::Class::Manual::Cookbook>.
4606 =item Value: ( 'update' | 'shared' | \$scalar )
4610 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4611 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4616 DBIx::Class supports arbitrary related data prefetching from multiple related
4617 sources. Any combination of relationship types and column sets are supported.
4618 If L<collapsing|/collapse> is requested, there is an additional requirement of
4619 selecting enough data to make every individual object uniquely identifiable.
4621 Here are some more involved examples, based on the following relationship map:
4624 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4625 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4626 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4628 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4630 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4634 my $rs = $schema->resultset('Tag')->search(
4643 The initial search results in SQL like the following:
4645 SELECT tag.*, cd.*, artist.* FROM tag
4646 JOIN cd ON tag.cd = cd.cdid
4647 JOIN artist ON cd.artist = artist.artistid
4649 L<DBIx::Class> has no need to go back to the database when we access the
4650 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4653 Simple prefetches will be joined automatically, so there is no need
4654 for a C<join> attribute in the above search.
4656 The L</prefetch> attribute can be used with any of the relationship types
4657 and multiple prefetches can be specified together. Below is a more complex
4658 example that prefetches a CD's artist, its liner notes (if present),
4659 the cover image, the tracks on that CD, and the guests on those
4662 my $rs = $schema->resultset('CD')->search(
4666 { artist => 'record_label'}, # belongs_to => belongs_to
4667 'liner_note', # might_have
4668 'cover_image', # has_one
4669 { tracks => 'guests' }, # has_many => has_many
4674 This will produce SQL like the following:
4676 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4680 ON artist.artistid = me.artistid
4681 JOIN record_label record_label
4682 ON record_label.labelid = artist.labelid
4683 LEFT JOIN track tracks
4684 ON tracks.cdid = me.cdid
4685 LEFT JOIN guest guests
4686 ON guests.trackid = track.trackid
4687 LEFT JOIN liner_notes liner_note
4688 ON liner_note.cdid = me.cdid
4689 JOIN cd_artwork cover_image
4690 ON cover_image.cdid = me.cdid
4693 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4694 C<tracks>, and C<guests> of the CD will all be available through the
4695 relationship accessors without the need for additional queries to the
4700 Prefetch does a lot of deep magic. As such, it may not behave exactly
4701 as you might expect.
4707 Prefetch uses the L</cache> to populate the prefetched relationships. This
4708 may or may not be what you want.
4712 If you specify a condition on a prefetched relationship, ONLY those
4713 rows that match the prefetched condition will be fetched into that relationship.
4714 This means that adding prefetch to a search() B<may alter> what is returned by
4715 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4717 my $artist_rs = $schema->resultset('Artist')->search({
4723 my $count = $artist_rs->first->cds->count;
4725 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4727 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4729 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4731 That cmp_ok() may or may not pass depending on the datasets involved. In other
4732 words the C<WHERE> condition would apply to the entire dataset, just like
4733 it would in regular SQL. If you want to add a condition only to the "right side"
4734 of a C<LEFT JOIN> - consider declaring and using a L<relationship with a custom
4735 condition|DBIx::Class::Relationship::Base/condition>
4739 =head1 DBIC BIND VALUES
4741 Because DBIC may need more information to bind values than just the column name
4742 and value itself, it uses a special format for both passing and receiving bind
4743 values. Each bind value should be composed of an arrayref of
4744 C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
4750 If present (in any form), this is what is being passed directly to bind_param.
4751 Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
4752 a single numerical type, while DBD::Pg takes a hashref if bind options.)
4754 If this is specified, all other bind options described below are ignored.
4758 If present, this is used to infer the actual bind attribute by passing to
4759 C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
4760 "data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
4762 Note that the data type is somewhat freeform (hence the sqlt_ prefix);
4763 currently drivers are expected to "Do the Right Thing" when given a common
4764 datatype name. (Not ideal, but that's what we got at this point.)
4768 Currently used to correctly allocate buffers for bind_param_inout().
4769 Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
4770 or to a sensible value based on the "data_type".
4774 Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
4775 explicitly specified they are never overridden). Also used by some weird DBDs,
4776 where the column name should be available at bind_param time (e.g. Oracle).
4780 For backwards compatibility and convenience, the following shortcuts are
4783 [ $name => $val ] === [ { dbic_colname => $name }, $val ]
4784 [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
4785 [ undef, $val ] === [ {}, $val ]
4786 $val === [ {}, $val ]
4788 =head1 AUTHOR AND CONTRIBUTORS
4790 See L<AUTHOR|DBIx::Class/AUTHOR> and L<CONTRIBUTORS|DBIx::Class/CONTRIBUTORS> in DBIx::Class
4794 You may distribute this code under the same terms as Perl itself.