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 $sep = quotemeta($sql_maker->name_sep);
1734 my $ident_re = $sql_maker->_quoted_ident_re;
1736 my $having_sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1739 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1740 # and if all fails for an utterly naive quoted scalar-with-function
1741 while ($having_sql =~ /
1742 $ident_re $sep ($ident_re)
1744 [\s,] \w+ \. (\w+) [\s,]
1746 [\s,] ($ident_re) [\s,]
1748 my $part = $sql_maker->_unquote($1 || $2 || $3); # one of them matched if we got here
1749 unless ($seen_having{$part}++) {
1756 my $colpiece = $sel_index->{$_} || $_;
1758 # unqualify join-based group_by's. Arcane but possible query
1759 # also horrible horrible hack to alias a column (not a func.)
1760 # (probably need to introduce SQLA syntax)
1761 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1764 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1766 push @{$sub_attrs->{select}}, $colpiece;
1770 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1771 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1774 return $rsrc->resultset_class
1775 ->new ($rsrc, $sub_attrs)
1777 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1778 ->get_column ('count');
1782 =head2 count_literal
1784 B<CAVEAT>: C<count_literal> is provided for Class::DBI compatibility and
1785 should only be used in that context. See L</search_literal> for further info.
1789 =item Arguments: $sql_fragment, @standalone_bind_values
1791 =item Return Value: $count
1795 Counts the results in a literal query. Equivalent to calling L</search_literal>
1796 with the passed arguments, then L</count>.
1800 sub count_literal { shift->search_literal(@_)->count; }
1806 =item Arguments: none
1808 =item Return Value: L<@result_objs|DBIx::Class::Manual::ResultClass>
1812 Returns all elements in the resultset.
1819 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1822 delete @{$self}{qw/_stashed_rows _stashed_results/};
1824 if (my $c = $self->get_cache) {
1828 $self->cursor->reset;
1830 my $objs = $self->_construct_results('fetch_all') || [];
1832 $self->set_cache($objs) if $self->{attrs}{cache};
1841 =item Arguments: none
1843 =item Return Value: $self
1847 Resets the resultset's cursor, so you can iterate through the elements again.
1848 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1856 delete @{$self}{qw/_stashed_rows _stashed_results/};
1857 $self->{all_cache_position} = 0;
1858 $self->cursor->reset;
1866 =item Arguments: none
1868 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1872 L<Resets|/reset> the resultset (causing a fresh query to storage) and returns
1873 an object for the first result (or C<undef> if the resultset is empty).
1878 return $_[0]->reset->next;
1884 # Determines whether and what type of subquery is required for the $rs operation.
1885 # If grouping is necessary either supplies its own, or verifies the current one
1886 # After all is done delegates to the proper storage method.
1888 sub _rs_update_delete {
1889 my ($self, $op, $values) = @_;
1891 my $rsrc = $self->result_source;
1892 my $storage = $rsrc->schema->storage;
1894 my $attrs = { %{$self->_resolved_attrs} };
1896 my $join_classifications;
1897 my ($existing_group_by) = delete @{$attrs}{qw(group_by _grouped_by_distinct)};
1899 # do we need a subquery for any reason?
1901 defined $existing_group_by
1903 # if {from} is unparseable wrap a subq
1904 ref($attrs->{from}) ne 'ARRAY'
1906 # limits call for a subq
1907 $self->_has_resolved_attr(qw/rows offset/)
1910 # simplify the joinmap, so we can further decide if a subq is necessary
1911 if (!$needs_subq and @{$attrs->{from}} > 1) {
1913 ($attrs->{from}, $join_classifications) =
1914 $storage->_prune_unused_joins ($attrs);
1916 # any non-pruneable non-local restricting joins imply subq
1917 $needs_subq = defined List::Util::first { $_ ne $attrs->{alias} } keys %{ $join_classifications->{restricting} || {} };
1920 # check if the head is composite (by now all joins are thrown out unless $needs_subq)
1922 (ref $attrs->{from}[0]) ne 'HASH'
1924 ref $attrs->{from}[0]{ $attrs->{from}[0]{-alias} }
1928 # do we need anything like a subquery?
1929 if (! $needs_subq) {
1930 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1931 # a condition containing 'me' or other table prefixes will not work
1932 # at all. Tell SQLMaker to dequalify idents via a gross hack.
1934 my $sqla = $rsrc->storage->sql_maker;
1935 local $sqla->{_dequalify_idents} = 1;
1936 \[ $sqla->_recurse_where($self->{cond}) ];
1940 # we got this far - means it is time to wrap a subquery
1941 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1943 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1949 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1950 delete $attrs->{$_} for qw/select as collapse/;
1951 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1953 # this will be consumed by the pruner waaaaay down the stack
1954 $attrs->{_force_prune_multiplying_joins} = 1;
1956 my $subrs = (ref $self)->new($rsrc, $attrs);
1958 if (@$idcols == 1) {
1959 $cond = { $idcols->[0] => { -in => $subrs->as_query } };
1961 elsif ($storage->_use_multicolumn_in) {
1962 # no syntax for calling this properly yet
1963 # !!! EXPERIMENTAL API !!! WILL CHANGE !!!
1964 $cond = $storage->sql_maker->_where_op_multicolumn_in (
1965 $idcols, # how do I convey a list of idents...? can binds reside on lhs?
1970 # if all else fails - get all primary keys and operate over a ORed set
1971 # wrap in a transaction for consistency
1972 # this is where the group_by/multiplication starts to matter
1976 # we do not need to check pre-multipliers, since if the premulti is there, its
1977 # parent (who is multi) will be there too
1978 keys %{ $join_classifications->{multiplying} || {} }
1980 # make sure if there is a supplied group_by it matches the columns compiled above
1981 # perfectly. Anything else can not be sanely executed on most databases so croak
1982 # right then and there
1983 if ($existing_group_by) {
1984 my @current_group_by = map
1985 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1990 join ("\x00", sort @current_group_by)
1992 join ("\x00", sort @{$attrs->{columns}} )
1994 $self->throw_exception (
1995 "You have just attempted a $op operation on a resultset which does group_by"
1996 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1997 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1998 . ' kind of queries. Please retry the operation with a modified group_by or'
1999 . ' without using one at all.'
2004 $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
2007 $guard = $storage->txn_scope_guard;
2009 for my $row ($subrs->cursor->all) {
2011 { $idcols->[$_] => $row->[$_] }
2018 my $res = $cond ? $storage->$op (
2020 $op eq 'update' ? $values : (),
2024 $guard->commit if $guard;
2033 =item Arguments: \%values
2035 =item Return Value: $underlying_storage_rv
2039 Sets the specified columns in the resultset to the supplied values in a
2040 single query. Note that this will not run any accessor/set_column/update
2041 triggers, nor will it update any result object instances derived from this
2042 resultset (this includes the contents of the L<resultset cache|/set_cache>
2043 if any). See L</update_all> if you need to execute any on-update
2044 triggers or cascades defined either by you or a
2045 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2047 The return value is a pass through of what the underlying
2048 storage backend returned, and may vary. See L<DBI/execute> for the most
2053 Note that L</update> does not process/deflate any of the values passed in.
2054 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
2055 ensure manually that any value passed to this method will stringify to
2056 something the RDBMS knows how to deal with. A notable example is the
2057 handling of L<DateTime> objects, for more info see:
2058 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
2063 my ($self, $values) = @_;
2064 $self->throw_exception('Values for update must be a hash')
2065 unless ref $values eq 'HASH';
2067 return $self->_rs_update_delete ('update', $values);
2074 =item Arguments: \%values
2076 =item Return Value: 1
2080 Fetches all objects and updates them one at a time via
2081 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
2082 triggers, while L</update> will not.
2087 my ($self, $values) = @_;
2088 $self->throw_exception('Values for update_all must be a hash')
2089 unless ref $values eq 'HASH';
2091 my $guard = $self->result_source->schema->txn_scope_guard;
2092 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
2101 =item Arguments: none
2103 =item Return Value: $underlying_storage_rv
2107 Deletes the rows matching this resultset in a single query. Note that this
2108 will not run any delete triggers, nor will it alter the
2109 L<in_storage|DBIx::Class::Row/in_storage> status of any result object instances
2110 derived from this resultset (this includes the contents of the
2111 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
2112 execute any on-delete triggers or cascades defined either by you or a
2113 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2115 The return value is a pass through of what the underlying storage backend
2116 returned, and may vary. See L<DBI/execute> for the most common case.
2122 $self->throw_exception('delete does not accept any arguments')
2125 return $self->_rs_update_delete ('delete');
2132 =item Arguments: none
2134 =item Return Value: 1
2138 Fetches all objects and deletes them one at a time via
2139 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2140 triggers, while L</delete> will not.
2146 $self->throw_exception('delete_all does not accept any arguments')
2149 my $guard = $self->result_source->schema->txn_scope_guard;
2150 $_->delete for $self->all;
2159 =item Arguments: [ \@column_list, \@row_values+ ] | [ \%col_data+ ]
2161 =item Return Value: L<\@result_objects|DBIx::Class::Manual::ResultClass> (scalar context) | L<@result_objects|DBIx::Class::Manual::ResultClass> (list context)
2165 Accepts either an arrayref of hashrefs or alternatively an arrayref of
2172 The context of this method call has an important effect on what is
2173 submitted to storage. In void context data is fed directly to fastpath
2174 insertion routines provided by the underlying storage (most often
2175 L<DBI/execute_for_fetch>), bypassing the L<new|DBIx::Class::Row/new> and
2176 L<insert|DBIx::Class::Row/insert> calls on the
2177 L<Result|DBIx::Class::Manual::ResultClass> class, including any
2178 augmentation of these methods provided by components. For example if you
2179 are using something like L<DBIx::Class::UUIDColumns> to create primary
2180 keys for you, you will find that your PKs are empty. In this case you
2181 will have to explicitly force scalar or list context in order to create
2186 In non-void (scalar or list) context, this method is simply a wrapper
2187 for L</create>. Depending on list or scalar context either a list of
2188 L<Result|DBIx::Class::Manual::ResultClass> objects or an arrayref
2189 containing these objects is returned.
2191 When supplying data in "arrayref of arrayrefs" invocation style, the
2192 first element should be a list of column names and each subsequent
2193 element should be a data value in the earlier specified column order.
2196 $schema->resultset("Artist")->populate([
2197 [ qw( artistid name ) ],
2198 [ 100, 'A Formally Unknown Singer' ],
2199 [ 101, 'A singer that jumped the shark two albums ago' ],
2200 [ 102, 'An actually cool singer' ],
2203 For the arrayref of hashrefs style each hashref should be a structure
2204 suitable for passing to L</create>. Multi-create is also permitted with
2207 $schema->resultset("Artist")->populate([
2208 { artistid => 4, name => 'Manufactured Crap', cds => [
2209 { title => 'My First CD', year => 2006 },
2210 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2213 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2214 { title => 'My parents sold me to a record company', year => 2005 },
2215 { title => 'Why Am I So Ugly?', year => 2006 },
2216 { title => 'I Got Surgery and am now Popular', year => 2007 }
2221 If you attempt a void-context multi-create as in the example above (each
2222 Artist also has the related list of CDs), and B<do not> supply the
2223 necessary autoinc foreign key information, this method will proxy to the
2224 less efficient L</create>, and then throw the Result objects away. In this
2225 case there are obviously no benefits to using this method over L</create>.
2232 # this is naive and just a quick check
2233 # the types will need to be checked more thoroughly when the
2234 # multi-source populate gets added
2236 ref $_[0] eq 'ARRAY'
2238 ( @{$_[0]} or return )
2240 ( ref $_[0][0] eq 'HASH' or ref $_[0][0] eq 'ARRAY' )
2243 ) or $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) {
2249 my (@results, $guard);
2251 if (ref $data->[0] eq 'ARRAY') {
2252 # column names only, nothing to do
2253 return if @$data == 1;
2255 $guard = $self->result_source->schema->storage->txn_scope_guard
2259 { my $vals = $_; $self->new_result({ map { $data->[0][$_] => $vals->[$_] } 0..$#{$data->[0]} })->insert }
2260 @{$data}[1 .. $#$data]
2265 $guard = $self->result_source->schema->storage->txn_scope_guard
2268 @results = map { $self->new_result($_)->insert } @$data;
2271 $guard->commit if $guard;
2272 return wantarray ? @results : \@results;
2275 # we have to deal with *possibly incomplete* related data
2276 # this means we have to walk the data structure twice
2277 # whether we want this or not
2278 # jnap, I hate you ;)
2279 my $rsrc = $self->result_source;
2280 my $rel_info = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2282 my ($colinfo, $colnames, $slices_with_rels);
2286 for my $i (0 .. $#$data) {
2288 my $current_slice_seen_rel_infos;
2290 ### Determine/Supplement collists
2291 ### BEWARE - This is a hot piece of code, a lot of weird idioms were used
2292 if( ref $data->[$i] eq 'ARRAY' ) {
2294 # positional(!) explicit column list
2296 # column names only, nothing to do
2297 return if @$data == 1;
2299 $colinfo->{$data->[0][$_]} = { pos => $_, name => $data->[0][$_] } and push @$colnames, $data->[0][$_]
2300 for 0 .. $#{$data->[0]};
2307 for (values %$colinfo) {
2308 if ($_->{is_rel} ||= (
2309 $rel_info->{$_->{name}}
2312 ref $data->[$i][$_->{pos}] eq 'ARRAY'
2314 ref $data->[$i][$_->{pos}] eq 'HASH'
2316 ( defined blessed $data->[$i][$_->{pos}] and $data->[$i][$_->{pos}]->isa('DBIx::Class::Row') )
2322 # moar sanity check... sigh
2323 for ( ref $data->[$i][$_->{pos}] eq 'ARRAY' ? @{$data->[$i][$_->{pos}]} : $data->[$i][$_->{pos}] ) {
2324 if ( defined blessed $_ and $_->isa('DBIx::Class::Row' ) ) {
2325 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2326 return my $throwaway = $self->populate(@_);
2330 push @$current_slice_seen_rel_infos, $rel_info->{$_->{name}};
2335 if ($current_slice_seen_rel_infos) {
2336 push @$slices_with_rels, { map { $colnames->[$_] => $data->[$i][$_] } 0 .. $#$colnames };
2338 # this is needed further down to decide whether or not to fallback to create()
2339 $colinfo->{$colnames->[$_]}{seen_null} ||= ! defined $data->[$i][$_]
2340 for 0 .. $#$colnames;
2343 elsif( ref $data->[$i] eq 'HASH' ) {
2345 for ( sort keys %{$data->[$i]} ) {
2347 $colinfo->{$_} ||= do {
2349 $self->throw_exception("Column '$_' must be present in supplied explicit column list")
2350 if $data_start; # it will be 0 on AoH, 1 on AoA
2352 push @$colnames, $_;
2355 { pos => $#$colnames, name => $_ }
2358 if ($colinfo->{$_}{is_rel} ||= (
2362 ref $data->[$i]{$_} eq 'ARRAY'
2364 ref $data->[$i]{$_} eq 'HASH'
2366 ( defined blessed $data->[$i]{$_} and $data->[$i]{$_}->isa('DBIx::Class::Row') )
2372 # moar sanity check... sigh
2373 for ( ref $data->[$i]{$_} eq 'ARRAY' ? @{$data->[$i]{$_}} : $data->[$i]{$_} ) {
2374 if ( defined blessed $_ and $_->isa('DBIx::Class::Row' ) ) {
2375 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2376 return my $throwaway = $self->populate(@_);
2380 push @$current_slice_seen_rel_infos, $rel_info->{$_};
2384 if ($current_slice_seen_rel_infos) {
2385 push @$slices_with_rels, $data->[$i];
2387 # this is needed further down to decide whether or not to fallback to create()
2388 $colinfo->{$_}{seen_null} ||= ! defined $data->[$i]{$_}
2389 for keys %{$data->[$i]};
2393 $self->throw_exception('Unexpected populate() data structure member type: ' . ref $data->[$i] );
2397 { $_->{attrs}{is_depends_on} }
2398 @{ $current_slice_seen_rel_infos || [] }
2400 carp_unique("Fast-path populate() of belongs_to relationship data is not possible - falling back to regular create()");
2401 return my $throwaway = $self->populate(@_);
2405 if( $slices_with_rels ) {
2407 # need to exclude the rel "columns"
2408 $colnames = [ grep { ! $colinfo->{$_}{is_rel} } @$colnames ];
2410 # extra sanity check - ensure the main source is in fact identifiable
2411 # the localizing of nullability is insane, but oh well... the use-case is legit
2412 my $ci = $rsrc->columns_info($colnames);
2414 $ci->{$_} = { %{$ci->{$_}}, is_nullable => 0 }
2415 for grep { ! $colinfo->{$_}{seen_null} } keys %$ci;
2417 unless( $rsrc->_identifying_column_set($ci) ) {
2418 carp_unique("Fast-path populate() of non-uniquely identifiable rows with related data is not possible - falling back to regular create()");
2419 return my $throwaway = $self->populate(@_);
2423 ### inherit the data locked in the conditions of the resultset
2424 my ($rs_data) = $self->_merge_with_rscond({});
2425 delete @{$rs_data}{@$colnames}; # passed-in stuff takes precedence
2427 # if anything left - decompose rs_data
2429 if (keys %$rs_data) {
2430 push @$rs_data_vals, $rs_data->{$_}
2431 for sort keys %$rs_data;
2436 $guard = $rsrc->schema->storage->txn_scope_guard
2437 if $slices_with_rels;
2439 ### main source data
2440 # FIXME - need to switch entirely to a coderef-based thing,
2441 # so that large sets aren't copied several times... I think
2442 $rsrc->storage->_insert_bulk(
2444 [ @$colnames, sort keys %$rs_data ],
2446 ref $data->[$_] eq 'ARRAY'
2448 $slices_with_rels ? [ @{$data->[$_]}[0..$#$colnames], @{$rs_data_vals||[]} ] # the collist changed
2449 : $rs_data_vals ? [ @{$data->[$_]}, @$rs_data_vals ]
2452 : [ @{$data->[$_]}{@$colnames}, @{$rs_data_vals||[]} ]
2453 } $data_start .. $#$data ],
2456 ### do the children relationships
2457 if ( $slices_with_rels ) {
2458 my @rels = grep { $colinfo->{$_}{is_rel} } keys %$colinfo
2459 or die 'wtf... please report a bug with DBIC_TRACE=1 output (stacktrace)';
2461 for my $sl (@$slices_with_rels) {
2463 my ($main_proto, $main_proto_rs);
2464 for my $rel (@rels) {
2465 next unless defined $sl->{$rel};
2469 (map { $_ => $sl->{$_} } @$colnames),
2472 unless (defined $colinfo->{$rel}{rs}) {
2474 $colinfo->{$rel}{rs} = $rsrc->related_source($rel)->resultset;
2476 $colinfo->{$rel}{fk_map} = { reverse %{ $rsrc->_resolve_relationship_condition(
2478 self_alias => "\xFE", # irrelevant
2479 foreign_alias => "\xFF", # irrelevant
2480 )->{identity_map} || {} } };
2484 $colinfo->{$rel}{rs}->search({ map # only so that we inherit them values properly, no actual search
2487 ( $main_proto_rs ||= $rsrc->resultset->search($main_proto) )
2488 ->get_column( $colinfo->{$rel}{fk_map}{$_} )
2492 keys %{$colinfo->{$rel}{fk_map}}
2493 })->populate( ref $sl->{$rel} eq 'ARRAY' ? $sl->{$rel} : [ $sl->{$rel} ] );
2500 $guard->commit if $guard;
2507 =item Arguments: none
2509 =item Return Value: L<$pager|Data::Page>
2513 Returns a L<Data::Page> object for the current resultset. Only makes
2514 sense for queries with a C<page> attribute.
2516 To get the full count of entries for a paged resultset, call
2517 C<total_entries> on the L<Data::Page> object.
2524 return $self->{pager} if $self->{pager};
2526 my $attrs = $self->{attrs};
2527 if (!defined $attrs->{page}) {
2528 $self->throw_exception("Can't create pager for non-paged rs");
2530 elsif ($attrs->{page} <= 0) {
2531 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2533 $attrs->{rows} ||= 10;
2535 # throw away the paging flags and re-run the count (possibly
2536 # with a subselect) to get the real total count
2537 my $count_attrs = { %$attrs };
2538 delete @{$count_attrs}{qw/rows offset page pager/};
2540 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2542 require DBIx::Class::ResultSet::Pager;
2543 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2544 sub { $total_rs->count }, #lazy-get the total
2546 $self->{attrs}{page},
2554 =item Arguments: $page_number
2556 =item Return Value: L<$resultset|/search>
2560 Returns a resultset for the $page_number page of the resultset on which page
2561 is called, where each page contains a number of rows equal to the 'rows'
2562 attribute set on the resultset (10 by default).
2567 my ($self, $page) = @_;
2568 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2575 =item Arguments: \%col_data
2577 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2581 Creates a new result object in the resultset's result class and returns
2582 it. The row is not inserted into the database at this point, call
2583 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2584 will tell you whether the result object has been inserted or not.
2586 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2591 my ($self, $values) = @_;
2593 $self->throw_exception( "new_result takes only one argument - a hashref of values" )
2596 $self->throw_exception( "Result object instantiation requires a hashref as argument" )
2597 unless (ref $values eq 'HASH');
2599 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2601 my $new = $self->result_class->new({
2603 ( @$cols_from_relations
2604 ? (-cols_from_relations => $cols_from_relations)
2607 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2611 reftype($new) eq 'HASH'
2617 carp_unique (sprintf (
2618 "%s->new returned a blessed empty hashref - a strong indicator something is wrong with its inheritance chain",
2619 $self->result_class,
2626 # _merge_with_rscond
2628 # Takes a simple hash of K/V data and returns its copy merged with the
2629 # condition already present on the resultset. Additionally returns an
2630 # arrayref of value/condition names, which were inferred from related
2631 # objects (this is needed for in-memory related objects)
2632 sub _merge_with_rscond {
2633 my ($self, $data) = @_;
2635 my ($implied_data, @cols_from_relations);
2637 my $alias = $self->{attrs}{alias};
2639 if (! defined $self->{cond}) {
2640 # just massage $data below
2642 elsif ($self->{cond} eq UNRESOLVABLE_CONDITION) {
2643 $implied_data = $self->{attrs}{related_objects}; # nothing might have been inserted yet
2644 @cols_from_relations = keys %{ $implied_data || {} };
2647 my $eqs = $self->result_source->schema->storage->_extract_fixed_condition_columns($self->{cond}, 'consider_nulls');
2648 $implied_data = { map {
2649 ( ($eqs->{$_}||'') eq UNRESOLVABLE_CONDITION ) ? () : ( $_ => $eqs->{$_} )
2655 { %{ $self->_remove_alias($_, $alias) } }
2656 # precedence must be given to passed values over values inherited from
2657 # the cond, so the order here is important.
2658 ( $implied_data||(), $data)
2660 \@cols_from_relations
2664 # _has_resolved_attr
2666 # determines if the resultset defines at least one
2667 # of the attributes supplied
2669 # used to determine if a subquery is necessary
2671 # supports some virtual attributes:
2673 # This will scan for any joins being present on the resultset.
2674 # It is not a mere key-search but a deep inspection of {from}
2677 sub _has_resolved_attr {
2678 my ($self, @attr_names) = @_;
2680 my $attrs = $self->_resolved_attrs;
2684 for my $n (@attr_names) {
2685 if (grep { $n eq $_ } (qw/-join/) ) {
2686 $extra_checks{$n}++;
2690 my $attr = $attrs->{$n};
2692 next if not defined $attr;
2694 if (ref $attr eq 'HASH') {
2695 return 1 if keys %$attr;
2697 elsif (ref $attr eq 'ARRAY') {
2705 # a resolved join is expressed as a multi-level from
2707 $extra_checks{-join}
2709 ref $attrs->{from} eq 'ARRAY'
2711 @{$attrs->{from}} > 1
2719 # Remove the specified alias from the specified query hash. A copy is made so
2720 # the original query is not modified.
2723 my ($self, $query, $alias) = @_;
2725 my %orig = %{ $query || {} };
2728 foreach my $key (keys %orig) {
2730 $unaliased{$key} = $orig{$key};
2733 $unaliased{$1} = $orig{$key}
2734 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2744 =item Arguments: none
2746 =item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
2750 Returns the SQL query and bind vars associated with the invocant.
2752 This is generally used as the RHS for a subquery.
2759 my $attrs = { %{ $self->_resolved_attrs } };
2761 my $aq = $self->result_source->storage->_select_args_to_query (
2762 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
2772 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2774 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2778 my $artist = $schema->resultset('Artist')->find_or_new(
2779 { artist => 'fred' }, { key => 'artists' });
2781 $cd->cd_to_producer->find_or_new({ producer => $producer },
2782 { key => 'primary' });
2784 Find an existing record from this resultset using L</find>. if none exists,
2785 instantiate a new result object and return it. The object will not be saved
2786 into your storage until you call L<DBIx::Class::Row/insert> on it.
2788 You most likely want this method when looking for existing rows using a unique
2789 constraint that is not the primary key, or looking for related rows.
2791 If you want objects to be saved immediately, use L</find_or_create> instead.
2793 B<Note>: Make sure to read the documentation of L</find> and understand the
2794 significance of the C<key> attribute, as its lack may skew your search, and
2795 subsequently result in spurious new objects.
2797 B<Note>: Take care when using C<find_or_new> with a table having
2798 columns with default values that you intend to be automatically
2799 supplied by the database (e.g. an auto_increment primary key column).
2800 In normal usage, the value of such columns should NOT be included at
2801 all in the call to C<find_or_new>, even when set to C<undef>.
2807 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2808 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2809 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2812 return $self->new_result($hash);
2819 =item Arguments: \%col_data
2821 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2825 Attempt to create a single new row or a row with multiple related rows
2826 in the table represented by the resultset (and related tables). This
2827 will not check for duplicate rows before inserting, use
2828 L</find_or_create> to do that.
2830 To create one row for this resultset, pass a hashref of key/value
2831 pairs representing the columns of the table and the values you wish to
2832 store. If the appropriate relationships are set up, foreign key fields
2833 can also be passed an object representing the foreign row, and the
2834 value will be set to its primary key.
2836 To create related objects, pass a hashref of related-object column values
2837 B<keyed on the relationship name>. If the relationship is of type C<multi>
2838 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2839 The process will correctly identify columns holding foreign keys, and will
2840 transparently populate them from the keys of the corresponding relation.
2841 This can be applied recursively, and will work correctly for a structure
2842 with an arbitrary depth and width, as long as the relationships actually
2843 exists and the correct column data has been supplied.
2845 Instead of hashrefs of plain related data (key/value pairs), you may
2846 also pass new or inserted objects. New objects (not inserted yet, see
2847 L</new_result>), will be inserted into their appropriate tables.
2849 Effectively a shortcut for C<< ->new_result(\%col_data)->insert >>.
2851 Example of creating a new row.
2853 $person_rs->create({
2854 name=>"Some Person",
2855 email=>"somebody@someplace.com"
2858 Example of creating a new row and also creating rows in a related C<has_many>
2859 or C<has_one> resultset. Note Arrayref.
2862 { artistid => 4, name => 'Manufactured Crap', cds => [
2863 { title => 'My First CD', year => 2006 },
2864 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2869 Example of creating a new row and also creating a row in a related
2870 C<belongs_to> resultset. Note Hashref.
2873 title=>"Music for Silly Walks",
2876 name=>"Silly Musician",
2884 When subclassing ResultSet never attempt to override this method. Since
2885 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2886 lot of the internals simply never call it, so your override will be
2887 bypassed more often than not. Override either L<DBIx::Class::Row/new>
2888 or L<DBIx::Class::Row/insert> depending on how early in the
2889 L</create> process you need to intervene. See also warning pertaining to
2897 #my ($self, $col_data) = @_;
2898 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
2899 return shift->new_result(shift)->insert;
2902 =head2 find_or_create
2906 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2908 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2912 $cd->cd_to_producer->find_or_create({ producer => $producer },
2913 { key => 'primary' });
2915 Tries to find a record based on its primary key or unique constraints; if none
2916 is found, creates one and returns that instead.
2918 my $cd = $schema->resultset('CD')->find_or_create({
2920 artist => 'Massive Attack',
2921 title => 'Mezzanine',
2925 Also takes an optional C<key> attribute, to search by a specific key or unique
2926 constraint. For example:
2928 my $cd = $schema->resultset('CD')->find_or_create(
2930 artist => 'Massive Attack',
2931 title => 'Mezzanine',
2933 { key => 'cd_artist_title' }
2936 B<Note>: Make sure to read the documentation of L</find> and understand the
2937 significance of the C<key> attribute, as its lack may skew your search, and
2938 subsequently result in spurious row creation.
2940 B<Note>: Because find_or_create() reads from the database and then
2941 possibly inserts based on the result, this method is subject to a race
2942 condition. Another process could create a record in the table after
2943 the find has completed and before the create has started. To avoid
2944 this problem, use find_or_create() inside a transaction.
2946 B<Note>: Take care when using C<find_or_create> with a table having
2947 columns with default values that you intend to be automatically
2948 supplied by the database (e.g. an auto_increment primary key column).
2949 In normal usage, the value of such columns should NOT be included at
2950 all in the call to C<find_or_create>, even when set to C<undef>.
2952 See also L</find> and L</update_or_create>. For information on how to declare
2953 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2955 If you need to know if an existing row was found or a new one created use
2956 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2957 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2960 my $cd = $schema->resultset('CD')->find_or_new({
2962 artist => 'Massive Attack',
2963 title => 'Mezzanine',
2967 if( !$cd->in_storage ) {
2974 sub find_or_create {
2976 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2977 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2978 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2981 return $self->new_result($hash)->insert;
2984 =head2 update_or_create
2988 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2990 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2994 $resultset->update_or_create({ col => $val, ... });
2996 Like L</find_or_create>, but if a row is found it is immediately updated via
2997 C<< $found_row->update (\%col_data) >>.
3000 Takes an optional C<key> attribute to search on a specific unique constraint.
3003 # In your application
3004 my $cd = $schema->resultset('CD')->update_or_create(
3006 artist => 'Massive Attack',
3007 title => 'Mezzanine',
3010 { key => 'cd_artist_title' }
3013 $cd->cd_to_producer->update_or_create({
3014 producer => $producer,
3020 B<Note>: Make sure to read the documentation of L</find> and understand the
3021 significance of the C<key> attribute, as its lack may skew your search, and
3022 subsequently result in spurious row creation.
3024 B<Note>: Take care when using C<update_or_create> with a table having
3025 columns with default values that you intend to be automatically
3026 supplied by the database (e.g. an auto_increment primary key column).
3027 In normal usage, the value of such columns should NOT be included at
3028 all in the call to C<update_or_create>, even when set to C<undef>.
3030 See also L</find> and L</find_or_create>. For information on how to declare
3031 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
3033 If you need to know if an existing row was updated or a new one created use
3034 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
3035 to call L<DBIx::Class::Row/insert> to save the newly created row to the
3040 sub update_or_create {
3042 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
3043 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3045 my $row = $self->find($cond, $attrs);
3047 $row->update($cond);
3051 return $self->new_result($cond)->insert;
3054 =head2 update_or_new
3058 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
3060 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
3064 $resultset->update_or_new({ col => $val, ... });
3066 Like L</find_or_new> but if a row is found it is immediately updated via
3067 C<< $found_row->update (\%col_data) >>.
3071 # In your application
3072 my $cd = $schema->resultset('CD')->update_or_new(
3074 artist => 'Massive Attack',
3075 title => 'Mezzanine',
3078 { key => 'cd_artist_title' }
3081 if ($cd->in_storage) {
3082 # the cd was updated
3085 # the cd is not yet in the database, let's insert it
3089 B<Note>: Make sure to read the documentation of L</find> and understand the
3090 significance of the C<key> attribute, as its lack may skew your search, and
3091 subsequently result in spurious new objects.
3093 B<Note>: Take care when using C<update_or_new> with a table having
3094 columns with default values that you intend to be automatically
3095 supplied by the database (e.g. an auto_increment primary key column).
3096 In normal usage, the value of such columns should NOT be included at
3097 all in the call to C<update_or_new>, even when set to C<undef>.
3099 See also L</find>, L</find_or_create> and L</find_or_new>.
3105 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
3106 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3108 my $row = $self->find( $cond, $attrs );
3109 if ( defined $row ) {
3110 $row->update($cond);
3114 return $self->new_result($cond);
3121 =item Arguments: none
3123 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass> | undef
3127 Gets the contents of the cache for the resultset, if the cache is set.
3129 The cache is populated either by using the L</prefetch> attribute to
3130 L</search> or by calling L</set_cache>.
3142 =item Arguments: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3144 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3148 Sets the contents of the cache for the resultset. Expects an arrayref
3149 of objects of the same class as those produced by the resultset. Note that
3150 if the cache is set, the resultset will return the cached objects rather
3151 than re-querying the database even if the cache attr is not set.
3153 The contents of the cache can also be populated by using the
3154 L</prefetch> attribute to L</search>.
3159 my ( $self, $data ) = @_;
3160 $self->throw_exception("set_cache requires an arrayref")
3161 if defined($data) && (ref $data ne 'ARRAY');
3162 $self->{all_cache} = $data;
3169 =item Arguments: none
3171 =item Return Value: undef
3175 Clears the cache for the resultset.
3180 shift->set_cache(undef);
3187 =item Arguments: none
3189 =item Return Value: true, if the resultset has been paginated
3197 return !!$self->{attrs}{page};
3204 =item Arguments: none
3206 =item Return Value: true, if the resultset has been ordered with C<order_by>.
3214 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
3217 =head2 related_resultset
3221 =item Arguments: $rel_name
3223 =item Return Value: L<$resultset|/search>
3227 Returns a related resultset for the supplied relationship name.
3229 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
3233 sub related_resultset {
3234 my ($self, $rel) = @_;
3236 return $self->{related_resultsets}{$rel}
3237 if defined $self->{related_resultsets}{$rel};
3239 return $self->{related_resultsets}{$rel} = do {
3240 my $rsrc = $self->result_source;
3241 my $rel_info = $rsrc->relationship_info($rel);
3243 $self->throw_exception(
3244 "search_related: result source '" . $rsrc->source_name .
3245 "' has no such relationship $rel")
3248 my $attrs = $self->_chain_relationship($rel);
3250 my $join_count = $attrs->{seen_join}{$rel};
3252 my $alias = $self->result_source->storage
3253 ->relname_to_table_alias($rel, $join_count);
3255 # since this is search_related, and we already slid the select window inwards
3256 # (the select/as attrs were deleted in the beginning), we need to flip all
3257 # left joins to inner, so we get the expected results
3258 # read the comment on top of the actual function to see what this does
3259 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
3262 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3263 delete @{$attrs}{qw(result_class alias)};
3265 my $rel_source = $rsrc->related_source($rel);
3269 # The reason we do this now instead of passing the alias to the
3270 # search_rs below is that if you wrap/overload resultset on the
3271 # source you need to know what alias it's -going- to have for things
3272 # to work sanely (e.g. RestrictWithObject wants to be able to add
3273 # extra query restrictions, and these may need to be $alias.)
3275 my $rel_attrs = $rel_source->resultset_attributes;
3276 local $rel_attrs->{alias} = $alias;
3278 $rel_source->resultset
3282 where => $attrs->{where},
3286 if (my $cache = $self->get_cache) {
3287 my @related_cache = map
3288 { $_->related_resultset($rel)->get_cache || () }
3292 $new->set_cache([ map @$_, @related_cache ]) if @related_cache == @$cache;
3299 =head2 current_source_alias
3303 =item Arguments: none
3305 =item Return Value: $source_alias
3309 Returns the current table alias for the result source this resultset is built
3310 on, that will be used in the SQL query. Usually it is C<me>.
3312 Currently the source alias that refers to the result set returned by a
3313 L</search>/L</find> family method depends on how you got to the resultset: it's
3314 C<me> by default, but eg. L</search_related> aliases it to the related result
3315 source name (and keeps C<me> referring to the original result set). The long
3316 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3317 (and make this method unnecessary).
3319 Thus it's currently necessary to use this method in predefined queries (see
3320 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3321 source alias of the current result set:
3323 # in a result set class
3325 my ($self, $user) = @_;
3327 my $me = $self->current_source_alias;
3329 return $self->search({
3330 "$me.modified" => $user->id,
3336 sub current_source_alias {
3337 return (shift->{attrs} || {})->{alias} || 'me';
3340 =head2 as_subselect_rs
3344 =item Arguments: none
3346 =item Return Value: L<$resultset|/search>
3350 Act as a barrier to SQL symbols. The resultset provided will be made into a
3351 "virtual view" by including it as a subquery within the from clause. From this
3352 point on, any joined tables are inaccessible to ->search on the resultset (as if
3353 it were simply where-filtered without joins). For example:
3355 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3357 # 'x' now pollutes the query namespace
3359 # So the following works as expected
3360 my $ok_rs = $rs->search({'x.other' => 1});
3362 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3363 # def) we look for one row with contradictory terms and join in another table
3364 # (aliased 'x_2') which we never use
3365 my $broken_rs = $rs->search({'x.name' => 'def'});
3367 my $rs2 = $rs->as_subselect_rs;
3369 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3370 my $not_joined_rs = $rs2->search({'x.other' => 1});
3372 # works as expected: finds a 'table' row related to two x rows (abc and def)
3373 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3375 Another example of when one might use this would be to select a subset of
3376 columns in a group by clause:
3378 my $rs = $schema->resultset('Bar')->search(undef, {
3379 group_by => [qw{ id foo_id baz_id }],
3380 })->as_subselect_rs->search(undef, {
3381 columns => [qw{ id foo_id }]
3384 In the above example normally columns would have to be equal to the group by,
3385 but because we isolated the group by into a subselect the above works.
3389 sub as_subselect_rs {
3392 my $attrs = $self->_resolved_attrs;
3394 my $fresh_rs = (ref $self)->new (
3395 $self->result_source
3398 # these pieces will be locked in the subquery
3399 delete $fresh_rs->{cond};
3400 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3402 return $fresh_rs->search( {}, {
3404 $attrs->{alias} => $self->as_query,
3405 -alias => $attrs->{alias},
3406 -rsrc => $self->result_source,
3408 alias => $attrs->{alias},
3412 # This code is called by search_related, and makes sure there
3413 # is clear separation between the joins before, during, and
3414 # after the relationship. This information is needed later
3415 # in order to properly resolve prefetch aliases (any alias
3416 # with a relation_chain_depth less than the depth of the
3417 # current prefetch is not considered)
3419 # The increments happen twice per join. An even number means a
3420 # relationship specified via a search_related, whereas an odd
3421 # number indicates a join/prefetch added via attributes
3423 # Also this code will wrap the current resultset (the one we
3424 # chain to) in a subselect IFF it contains limiting attributes
3425 sub _chain_relationship {
3426 my ($self, $rel) = @_;
3427 my $source = $self->result_source;
3428 my $attrs = { %{$self->{attrs}||{}} };
3430 # we need to take the prefetch the attrs into account before we
3431 # ->_resolve_join as otherwise they get lost - captainL
3432 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3434 delete @{$attrs}{qw/join prefetch collapse group_by distinct _grouped_by_distinct select as columns +select +as +columns/};
3436 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3439 my @force_subq_attrs = qw/offset rows group_by having/;
3442 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3444 $self->_has_resolved_attr (@force_subq_attrs)
3446 # Nuke the prefetch (if any) before the new $rs attrs
3447 # are resolved (prefetch is useless - we are wrapping
3448 # a subquery anyway).
3449 my $rs_copy = $self->search;
3450 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3451 $rs_copy->{attrs}{join},
3452 delete $rs_copy->{attrs}{prefetch},
3457 -alias => $attrs->{alias},
3458 $attrs->{alias} => $rs_copy->as_query,
3460 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3461 $seen->{-relation_chain_depth} = 0;
3463 elsif ($attrs->{from}) { #shallow copy suffices
3464 $from = [ @{$attrs->{from}} ];
3469 -alias => $attrs->{alias},
3470 $attrs->{alias} => $source->from,
3474 my $jpath = ($seen->{-relation_chain_depth})
3475 ? $from->[-1][0]{-join_path}
3478 my @requested_joins = $source->_resolve_join(
3485 push @$from, @requested_joins;
3487 $seen->{-relation_chain_depth}++;
3489 # if $self already had a join/prefetch specified on it, the requested
3490 # $rel might very well be already included. What we do in this case
3491 # is effectively a no-op (except that we bump up the chain_depth on
3492 # the join in question so we could tell it *is* the search_related)
3495 # we consider the last one thus reverse
3496 for my $j (reverse @requested_joins) {
3497 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3498 if ($rel eq $last_j) {
3499 $j->[0]{-relation_chain_depth}++;
3505 unless ($already_joined) {
3506 push @$from, $source->_resolve_join(
3514 $seen->{-relation_chain_depth}++;
3516 return {%$attrs, from => $from, seen_join => $seen};
3519 sub _resolved_attrs {
3521 return $self->{_attrs} if $self->{_attrs};
3523 my $attrs = { %{ $self->{attrs} || {} } };
3524 my $source = $attrs->{result_source} = $self->result_source;
3525 my $alias = $attrs->{alias};
3527 $self->throw_exception("Specifying distinct => 1 in conjunction with collapse => 1 is unsupported")
3528 if $attrs->{collapse} and $attrs->{distinct};
3530 # default selection list
3531 $attrs->{columns} = [ $source->columns ]
3532 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3534 # merge selectors together
3535 for (qw/columns select as/) {
3536 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3537 if $attrs->{$_} or $attrs->{"+$_"};
3540 # disassemble columns
3542 if (my $cols = delete $attrs->{columns}) {
3543 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3544 if (ref $c eq 'HASH') {
3545 for my $as (sort keys %$c) {
3546 push @sel, $c->{$as};
3557 # when trying to weed off duplicates later do not go past this point -
3558 # everything added from here on is unbalanced "anyone's guess" stuff
3559 my $dedup_stop_idx = $#as;
3561 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3563 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3564 if $attrs->{select};
3566 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3567 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3569 # disqualify all $alias.col as-bits (inflate-map mandated)
3570 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3572 # de-duplicate the result (remove *identical* select/as pairs)
3573 # and also die on duplicate {as} pointing to different {select}s
3574 # not using a c-style for as the condition is prone to shrinkage
3577 while ($i <= $dedup_stop_idx) {
3578 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3583 elsif ($seen->{$as[$i]}++) {
3584 $self->throw_exception(
3585 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3593 $attrs->{select} = \@sel;
3594 $attrs->{as} = \@as;
3596 $attrs->{from} ||= [{
3598 -alias => $self->{attrs}{alias},
3599 $self->{attrs}{alias} => $source->from,
3602 if ( $attrs->{join} || $attrs->{prefetch} ) {
3604 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3605 if ref $attrs->{from} ne 'ARRAY';
3607 my $join = (delete $attrs->{join}) || {};
3609 if ( defined $attrs->{prefetch} ) {
3610 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3613 $attrs->{from} = # have to copy here to avoid corrupting the original
3615 @{ $attrs->{from} },
3616 $source->_resolve_join(
3619 { %{ $attrs->{seen_join} || {} } },
3620 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3621 ? $attrs->{from}[-1][0]{-join_path}
3628 if ( defined $attrs->{order_by} ) {
3629 $attrs->{order_by} = (
3630 ref( $attrs->{order_by} ) eq 'ARRAY'
3631 ? [ @{ $attrs->{order_by} } ]
3632 : [ $attrs->{order_by} || () ]
3636 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3637 $attrs->{group_by} = [ $attrs->{group_by} ];
3641 # generate selections based on the prefetch helper
3642 my ($prefetch, @prefetch_select, @prefetch_as);
3643 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3644 if defined $attrs->{prefetch};
3648 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3649 if $attrs->{_dark_selector};
3651 $self->throw_exception("Specifying prefetch in conjunction with an explicit collapse => 0 is unsupported")
3652 if defined $attrs->{collapse} and ! $attrs->{collapse};
3654 $attrs->{collapse} = 1;
3656 # this is a separate structure (we don't look in {from} directly)
3657 # as the resolver needs to shift things off the lists to work
3658 # properly (identical-prefetches on different branches)
3660 if (ref $attrs->{from} eq 'ARRAY') {
3662 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3664 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3665 next unless $j->[0]{-alias};
3666 next unless $j->[0]{-join_path};
3667 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3669 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3672 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3673 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3677 my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map );
3679 # save these for after distinct resolution
3680 @prefetch_select = map { $_->[0] } @prefetch;
3681 @prefetch_as = map { $_->[1] } @prefetch;
3684 # run through the resulting joinstructure (starting from our current slot)
3685 # and unset collapse if proven unnecessary
3687 # also while we are at it find out if the current root source has
3688 # been premultiplied by previous related_source chaining
3690 # this allows to predict whether a root object with all other relation
3691 # data set to NULL is in fact unique
3692 if ($attrs->{collapse}) {
3694 if (ref $attrs->{from} eq 'ARRAY') {
3696 if (@{$attrs->{from}} == 1) {
3697 # no joins - no collapse
3698 $attrs->{collapse} = 0;
3701 # find where our table-spec starts
3702 my @fromlist = @{$attrs->{from}};
3704 my $t = shift @fromlist;
3707 # me vs join from-spec distinction - a ref means non-root
3708 if (ref $t eq 'ARRAY') {
3710 $is_multi ||= ! $t->{-is_single};
3712 last if ($t->{-alias} && $t->{-alias} eq $alias);
3713 $attrs->{_main_source_premultiplied} ||= $is_multi;
3716 # no non-singles remaining, nor any premultiplication - nothing to collapse
3718 ! $attrs->{_main_source_premultiplied}
3720 ! List::Util::first { ! $_->[0]{-is_single} } @fromlist
3722 $attrs->{collapse} = 0;
3728 # if we can not analyze the from - err on the side of safety
3729 $attrs->{_main_source_premultiplied} = 1;
3733 # generate the distinct induced group_by before injecting the prefetched select/as parts
3734 if (delete $attrs->{distinct}) {
3735 if ($attrs->{group_by}) {
3736 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3739 $attrs->{_grouped_by_distinct} = 1;
3740 # distinct affects only the main selection part, not what prefetch may add below
3741 ($attrs->{group_by}, my $new_order) = $source->storage->_group_over_selection($attrs);
3743 # FIXME possibly ignore a rewritten order_by (may turn out to be an issue)
3744 # The thinking is: if we are collapsing the subquerying prefetch engine will
3745 # rip stuff apart for us anyway, and we do not want to have a potentially
3746 # function-converted external order_by
3747 # ( there is an explicit if ( collapse && _grouped_by_distinct ) check in DBIHacks )
3748 $attrs->{order_by} = $new_order unless $attrs->{collapse};
3752 # inject prefetch-bound selection (if any)
3753 push @{$attrs->{select}}, @prefetch_select;
3754 push @{$attrs->{as}}, @prefetch_as;
3756 $attrs->{_simple_passthrough_construction} = !(
3759 grep { $_ =~ /\./ } @{$attrs->{as}}
3762 # if both page and offset are specified, produce a combined offset
3763 # even though it doesn't make much sense, this is what pre 081xx has
3765 if (my $page = delete $attrs->{page}) {
3767 ($attrs->{rows} * ($page - 1))
3769 ($attrs->{offset} || 0)
3773 return $self->{_attrs} = $attrs;
3777 my ($self, $attr) = @_;
3779 if (ref $attr eq 'HASH') {
3780 return $self->_rollout_hash($attr);
3781 } elsif (ref $attr eq 'ARRAY') {
3782 return $self->_rollout_array($attr);
3788 sub _rollout_array {
3789 my ($self, $attr) = @_;
3792 foreach my $element (@{$attr}) {
3793 if (ref $element eq 'HASH') {
3794 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3795 } elsif (ref $element eq 'ARRAY') {
3796 # XXX - should probably recurse here
3797 push( @rolled_array, @{$self->_rollout_array($element)} );
3799 push( @rolled_array, $element );
3802 return \@rolled_array;
3806 my ($self, $attr) = @_;
3809 foreach my $key (keys %{$attr}) {
3810 push( @rolled_array, { $key => $attr->{$key} } );
3812 return \@rolled_array;
3815 sub _calculate_score {
3816 my ($self, $a, $b) = @_;
3818 if (defined $a xor defined $b) {
3821 elsif (not defined $a) {
3825 if (ref $b eq 'HASH') {
3826 my ($b_key) = keys %{$b};
3827 if (ref $a eq 'HASH') {
3828 my ($a_key) = keys %{$a};
3829 if ($a_key eq $b_key) {
3830 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3835 return ($a eq $b_key) ? 1 : 0;
3838 if (ref $a eq 'HASH') {
3839 my ($a_key) = keys %{$a};
3840 return ($b eq $a_key) ? 1 : 0;
3842 return ($b eq $a) ? 1 : 0;
3847 sub _merge_joinpref_attr {
3848 my ($self, $orig, $import) = @_;
3850 return $import unless defined($orig);
3851 return $orig unless defined($import);
3853 $orig = $self->_rollout_attr($orig);
3854 $import = $self->_rollout_attr($import);
3857 foreach my $import_element ( @{$import} ) {
3858 # find best candidate from $orig to merge $b_element into
3859 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3860 foreach my $orig_element ( @{$orig} ) {
3861 my $score = $self->_calculate_score( $orig_element, $import_element );
3862 if ($score > $best_candidate->{score}) {
3863 $best_candidate->{position} = $position;
3864 $best_candidate->{score} = $score;
3868 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3869 $import_key = '' if not defined $import_key;
3871 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3872 push( @{$orig}, $import_element );
3874 my $orig_best = $orig->[$best_candidate->{position}];
3875 # merge orig_best and b_element together and replace original with merged
3876 if (ref $orig_best ne 'HASH') {
3877 $orig->[$best_candidate->{position}] = $import_element;
3878 } elsif (ref $import_element eq 'HASH') {
3879 my ($key) = keys %{$orig_best};
3880 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3883 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3886 return @$orig ? $orig : ();
3894 require Hash::Merge;
3895 my $hm = Hash::Merge->new;
3897 $hm->specify_behavior({
3900 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3902 if ($defl xor $defr) {
3903 return [ $defl ? $_[0] : $_[1] ];
3908 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3912 return [$_[0], $_[1]];
3916 return $_[1] if !defined $_[0];
3917 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3918 return [$_[0], @{$_[1]}]
3921 return [] if !defined $_[0] and !keys %{$_[1]};
3922 return [ $_[1] ] if !defined $_[0];
3923 return [ $_[0] ] if !keys %{$_[1]};
3924 return [$_[0], $_[1]]
3929 return $_[0] if !defined $_[1];
3930 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3931 return [@{$_[0]}, $_[1]]
3934 my @ret = @{$_[0]} or return $_[1];
3935 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3936 my %idx = map { $_ => 1 } @ret;
3937 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3941 return [ $_[1] ] if ! @{$_[0]};
3942 return $_[0] if !keys %{$_[1]};
3943 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3944 return [ @{$_[0]}, $_[1] ];
3949 return [] if !keys %{$_[0]} and !defined $_[1];
3950 return [ $_[0] ] if !defined $_[1];
3951 return [ $_[1] ] if !keys %{$_[0]};
3952 return [$_[0], $_[1]]
3955 return [] if !keys %{$_[0]} and !@{$_[1]};
3956 return [ $_[0] ] if !@{$_[1]};
3957 return $_[1] if !keys %{$_[0]};
3958 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3959 return [ $_[0], @{$_[1]} ];
3962 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3963 return [ $_[0] ] if !keys %{$_[1]};
3964 return [ $_[1] ] if !keys %{$_[0]};
3965 return [ $_[0] ] if $_[0] eq $_[1];
3966 return [ $_[0], $_[1] ];
3969 } => 'DBIC_RS_ATTR_MERGER');
3973 return $hm->merge ($_[1], $_[2]);
3977 sub STORABLE_freeze {
3978 my ($self, $cloning) = @_;
3979 my $to_serialize = { %$self };
3981 # A cursor in progress can't be serialized (and would make little sense anyway)
3982 # the parser can be regenerated (and can't be serialized)
3983 delete @{$to_serialize}{qw/cursor _row_parser _result_inflator/};
3985 # nor is it sensical to store a not-yet-fired-count pager
3986 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3987 delete $to_serialize->{pager};
3990 Storable::nfreeze($to_serialize);
3993 # need this hook for symmetry
3995 my ($self, $cloning, $serialized) = @_;
3997 %$self = %{ Storable::thaw($serialized) };
4003 =head2 throw_exception
4005 See L<DBIx::Class::Schema/throw_exception> for details.
4009 sub throw_exception {
4012 if (ref $self and my $rsrc = $self->result_source) {
4013 $rsrc->throw_exception(@_)
4016 DBIx::Class::Exception->throw(@_);
4024 # XXX: FIXME: Attributes docs need clearing up
4028 Attributes are used to refine a ResultSet in various ways when
4029 searching for data. They can be passed to any method which takes an
4030 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
4033 Default attributes can be set on the result class using
4034 L<DBIx::Class::ResultSource/resultset_attributes>. (Please read
4035 the CAVEATS on that feature before using it!)
4037 These are in no particular order:
4043 =item Value: ( $order_by | \@order_by | \%order_by )
4047 Which column(s) to order the results by.
4049 [The full list of suitable values is documented in
4050 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
4053 If a single column name, or an arrayref of names is supplied, the
4054 argument is passed through directly to SQL. The hashref syntax allows
4055 for connection-agnostic specification of ordering direction:
4057 For descending order:
4059 order_by => { -desc => [qw/col1 col2 col3/] }
4061 For explicit ascending order:
4063 order_by => { -asc => 'col' }
4065 The old scalarref syntax (i.e. order_by => \'year DESC') is still
4066 supported, although you are strongly encouraged to use the hashref
4067 syntax as outlined above.
4073 =item Value: \@columns | \%columns | $column
4077 Shortcut to request a particular set of columns to be retrieved. Each
4078 column spec may be a string (a table column name), or a hash (in which
4079 case the key is the C<as> value, and the value is used as the C<select>
4080 expression). Adds the L</current_source_alias> onto the start of any column without a C<.> in
4081 it and sets C<select> from that, then auto-populates C<as> from
4082 C<select> as normal. (You may also use the C<cols> attribute, as in
4083 earlier versions of DBIC, but this is deprecated)
4085 Essentially C<columns> does the same as L</select> and L</as>.
4087 columns => [ 'some_column', { dbic_slot => 'another_column' } ]
4091 select => [qw(some_column another_column)],
4092 as => [qw(some_column dbic_slot)]
4094 If you want to individually retrieve related columns (in essence perform
4095 manual prefetch) you have to make sure to specify the correct inflation slot
4096 chain such that it matches existing relationships:
4098 my $rs = $schema->resultset('Artist')->search({}, {
4099 # required to tell DBIC to collapse has_many relationships
4101 join => { cds => 'tracks'},
4103 'cds.cdid' => 'cds.cdid',
4104 'cds.tracks.title' => 'tracks.title',
4110 B<NOTE:> You B<MUST> explicitly quote C<'+columns'> when using this attribute.
4111 Not doing so causes Perl to incorrectly interpret C<+columns> as a bareword
4112 with a unary plus operator before it, which is the same as simply C<columns>.
4116 =item Value: \@extra_columns
4120 Indicates additional columns to be selected from storage. Works the same as
4121 L</columns> but adds columns to the current selection. (You may also use the
4122 C<include_columns> attribute, as in earlier versions of DBIC, but this is
4125 $schema->resultset('CD')->search(undef, {
4126 '+columns' => ['artist.name'],
4130 would return all CDs and include a 'name' column to the information
4131 passed to object inflation. Note that the 'artist' is the name of the
4132 column (or relationship) accessor, and 'name' is the name of the column
4133 accessor in the related table.
4139 =item Value: \@select_columns
4143 Indicates which columns should be selected from the storage. You can use
4144 column names, or in the case of RDBMS back ends, function or stored procedure
4147 $rs = $schema->resultset('Employee')->search(undef, {
4150 { count => 'employeeid' },
4151 { max => { length => 'name' }, -as => 'longest_name' }
4156 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
4158 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
4159 use L</select>, to instruct DBIx::Class how to store the result of the column.
4161 Also note that the L</as> attribute has B<nothing to do> with the SQL-side
4162 C<AS> identifier aliasing. You B<can> alias a function (so you can use it e.g.
4163 in an C<ORDER BY> clause), however this is done via the C<-as> B<select
4164 function attribute> supplied as shown in the example above.
4168 B<NOTE:> You B<MUST> explicitly quote C<'+select'> when using this attribute.
4169 Not doing so causes Perl to incorrectly interpret C<+select> as a bareword
4170 with a unary plus operator before it, which is the same as simply C<select>.
4174 =item Value: \@extra_select_columns
4178 Indicates additional columns to be selected from storage. Works the same as
4179 L</select> but adds columns to the current selection, instead of specifying
4180 a new explicit list.
4186 =item Value: \@inflation_names
4190 Indicates DBIC-side names for object inflation. That is L</as> indicates the
4191 slot name in which the column value will be stored within the
4192 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
4193 identifier by the C<get_column> method (or via the object accessor B<if one
4194 with the same name already exists>) as shown below.
4196 The L</as> attribute has B<nothing to do> with the SQL-side identifier
4197 aliasing C<AS>. See L</select> for details.
4199 $rs = $schema->resultset('Employee')->search(undef, {
4202 { count => 'employeeid' },
4203 { max => { length => 'name' }, -as => 'longest_name' }
4212 If the object against which the search is performed already has an accessor
4213 matching a column name specified in C<as>, the value can be retrieved using
4214 the accessor as normal:
4216 my $name = $employee->name();
4218 If on the other hand an accessor does not exist in the object, you need to
4219 use C<get_column> instead:
4221 my $employee_count = $employee->get_column('employee_count');
4223 You can create your own accessors if required - see
4224 L<DBIx::Class::Manual::Cookbook> for details.
4228 B<NOTE:> You B<MUST> explicitly quote C<'+as'> when using this attribute.
4229 Not doing so causes Perl to incorrectly interpret C<+as> as a bareword
4230 with a unary plus operator before it, which is the same as simply C<as>.
4234 =item Value: \@extra_inflation_names
4238 Indicates additional inflation names for selectors added via L</+select>. See L</as>.
4244 =item Value: ($rel_name | \@rel_names | \%rel_names)
4248 Contains a list of relationships that should be joined for this query. For
4251 # Get CDs by Nine Inch Nails
4252 my $rs = $schema->resultset('CD')->search(
4253 { 'artist.name' => 'Nine Inch Nails' },
4254 { join => 'artist' }
4257 Can also contain a hash reference to refer to the other relation's relations.
4260 package MyApp::Schema::Track;
4261 use base qw/DBIx::Class/;
4262 __PACKAGE__->table('track');
4263 __PACKAGE__->add_columns(qw/trackid cd position title/);
4264 __PACKAGE__->set_primary_key('trackid');
4265 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
4268 # In your application
4269 my $rs = $schema->resultset('Artist')->search(
4270 { 'track.title' => 'Teardrop' },
4272 join => { cd => 'track' },
4273 order_by => 'artist.name',
4277 You need to use the relationship (not the table) name in conditions,
4278 because they are aliased as such. The current table is aliased as "me", so
4279 you need to use me.column_name in order to avoid ambiguity. For example:
4281 # Get CDs from 1984 with a 'Foo' track
4282 my $rs = $schema->resultset('CD')->search(
4285 'tracks.name' => 'Foo'
4287 { join => 'tracks' }
4290 If the same join is supplied twice, it will be aliased to <rel>_2 (and
4291 similarly for a third time). For e.g.
4293 my $rs = $schema->resultset('Artist')->search({
4294 'cds.title' => 'Down to Earth',
4295 'cds_2.title' => 'Popular',
4297 join => [ qw/cds cds/ ],
4300 will return a set of all artists that have both a cd with title 'Down
4301 to Earth' and a cd with title 'Popular'.
4303 If you want to fetch related objects from other tables as well, see L</prefetch>
4306 NOTE: An internal join-chain pruner will discard certain joins while
4307 constructing the actual SQL query, as long as the joins in question do not
4308 affect the retrieved result. This for example includes 1:1 left joins
4309 that are not part of the restriction specification (WHERE/HAVING) nor are
4310 a part of the query selection.
4312 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4318 =item Value: (0 | 1)
4322 When set to a true value, indicates that any rows fetched from joined has_many
4323 relationships are to be aggregated into the corresponding "parent" object. For
4324 example, the resultset:
4326 my $rs = $schema->resultset('CD')->search({}, {
4327 '+columns' => [ qw/ tracks.title tracks.position / ],
4332 While executing the following query:
4334 SELECT me.*, tracks.title, tracks.position
4336 LEFT JOIN track tracks
4337 ON tracks.cdid = me.cdid
4339 Will return only as many objects as there are rows in the CD source, even
4340 though the result of the query may span many rows. Each of these CD objects
4341 will in turn have multiple "Track" objects hidden behind the has_many
4342 generated accessor C<tracks>. Without C<< collapse => 1 >>, the return values
4343 of this resultset would be as many CD objects as there are tracks (a "Cartesian
4344 product"), with each CD object containing exactly one of all fetched Track data.
4346 When a collapse is requested on a non-ordered resultset, an order by some
4347 unique part of the main source (the left-most table) is inserted automatically.
4348 This is done so that the resultset is allowed to be "lazy" - calling
4349 L<< $rs->next|/next >> will fetch only as many rows as it needs to build the next
4350 object with all of its related data.
4352 If an L</order_by> is already declared, and orders the resultset in a way that
4353 makes collapsing as described above impossible (e.g. C<< ORDER BY
4354 has_many_rel.column >> or C<ORDER BY RANDOM()>), DBIC will automatically
4355 switch to "eager" mode and slurp the entire resultset before constructing the
4356 first object returned by L</next>.
4358 Setting this attribute on a resultset that does not join any has_many
4359 relations is a no-op.
4361 For a more in-depth discussion, see L</PREFETCHING>.
4367 =item Value: ($rel_name | \@rel_names | \%rel_names)
4371 This attribute is a shorthand for specifying a L</join> spec, adding all
4372 columns from the joined related sources as L</+columns> and setting
4373 L</collapse> to a true value. It can be thought of as a rough B<superset>
4374 of the L</join> attribute.
4376 For example, the following two queries are equivalent:
4378 my $rs = $schema->resultset('Artist')->search({}, {
4379 prefetch => { cds => ['genre', 'tracks' ] },
4384 my $rs = $schema->resultset('Artist')->search({}, {
4385 join => { cds => ['genre', 'tracks' ] },
4389 { +{ "cds.$_" => "cds.$_" } }
4390 $schema->source('Artist')->related_source('cds')->columns
4393 { +{ "cds.genre.$_" => "genre.$_" } }
4394 $schema->source('Artist')->related_source('cds')->related_source('genre')->columns
4397 { +{ "cds.tracks.$_" => "tracks.$_" } }
4398 $schema->source('Artist')->related_source('cds')->related_source('tracks')->columns
4403 Both producing the following SQL:
4405 SELECT me.artistid, me.name, me.rank, me.charfield,
4406 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track,
4407 genre.genreid, genre.name,
4408 tracks.trackid, tracks.cd, tracks.position, tracks.title, tracks.last_updated_on, tracks.last_updated_at
4411 ON cds.artist = me.artistid
4412 LEFT JOIN genre genre
4413 ON genre.genreid = cds.genreid
4414 LEFT JOIN track tracks
4415 ON tracks.cd = cds.cdid
4416 ORDER BY me.artistid
4418 While L</prefetch> implies a L</join>, it is ok to mix the two together, as
4419 the arguments are properly merged and generally do the right thing. For
4420 example, you may want to do the following:
4422 my $artists_and_cds_without_genre = $schema->resultset('Artist')->search(
4423 { 'genre.genreid' => undef },
4425 join => { cds => 'genre' },
4430 Which generates the following SQL:
4432 SELECT me.artistid, me.name, me.rank, me.charfield,
4433 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track
4436 ON cds.artist = me.artistid
4437 LEFT JOIN genre genre
4438 ON genre.genreid = cds.genreid
4439 WHERE genre.genreid IS NULL
4440 ORDER BY me.artistid
4442 For a more in-depth discussion, see L</PREFETCHING>.
4448 =item Value: $source_alias
4452 Sets the source alias for the query. Normally, this defaults to C<me>, but
4453 nested search queries (sub-SELECTs) might need specific aliases set to
4454 reference inner queries. For example:
4457 ->related_resultset('CDs')
4458 ->related_resultset('Tracks')
4460 'track.id' => { -ident => 'none_search.id' },
4464 my $ids = $self->search({
4467 alias => 'none_search',
4468 group_by => 'none_search.id',
4469 })->get_column('id')->as_query;
4471 $self->search({ id => { -in => $ids } })
4473 This attribute is directly tied to L</current_source_alias>.
4483 Makes the resultset paged and specifies the page to retrieve. Effectively
4484 identical to creating a non-pages resultset and then calling ->page($page)
4487 If L</rows> attribute is not specified it defaults to 10 rows per page.
4489 When you have a paged resultset, L</count> will only return the number
4490 of rows in the page. To get the total, use the L</pager> and call
4491 C<total_entries> on it.
4501 Specifies the maximum number of rows for direct retrieval or the number of
4502 rows per page if the page attribute or method is used.
4508 =item Value: $offset
4512 Specifies the (zero-based) row number for the first row to be returned, or the
4513 of the first row of the first page if paging is used.
4515 =head2 software_limit
4519 =item Value: (0 | 1)
4523 When combined with L</rows> and/or L</offset> the generated SQL will not
4524 include any limit dialect stanzas. Instead the entire result will be selected
4525 as if no limits were specified, and DBIC will perform the limit locally, by
4526 artificially advancing and finishing the resulting L</cursor>.
4528 This is the recommended way of performing resultset limiting when no sane RDBMS
4529 implementation is available (e.g.
4530 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4531 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4537 =item Value: \@columns
4541 A arrayref of columns to group by. Can include columns of joined tables.
4543 group_by => [qw/ column1 column2 ... /]
4549 =item Value: $condition
4553 The HAVING operator specifies a B<secondary> condition applied to the set
4554 after the grouping calculations have been done. In other words it is a
4555 constraint just like L</where> (and accepting the same
4556 L<SQL::Abstract syntax|SQL::Abstract/WHERE CLAUSES>) applied to the data
4557 as it exists after GROUP BY has taken place. Specifying L</having> without
4558 L</group_by> is a logical mistake, and a fatal error on most RDBMS engines.
4562 having => { 'count_employee' => { '>=', 100 } }
4564 or with an in-place function in which case literal SQL is required:
4566 having => \[ 'count(employee) >= ?', 100 ]
4572 =item Value: (0 | 1)
4576 Set to 1 to automatically generate a L</group_by> clause based on the selection
4577 (including intelligent handling of L</order_by> contents). Note that the group
4578 criteria calculation takes place over the B<final> selection. This includes
4579 any L</+columns>, L</+select> or L</order_by> additions in subsequent
4580 L</search> calls, and standalone columns selected via
4581 L<DBIx::Class::ResultSetColumn> (L</get_column>). A notable exception are the
4582 extra selections specified via L</prefetch> - such selections are explicitly
4583 excluded from group criteria calculations.
4585 If the final ResultSet also explicitly defines a L</group_by> attribute, this
4586 setting is ignored and an appropriate warning is issued.
4592 Adds to the WHERE clause.
4594 # only return rows WHERE deleted IS NULL for all searches
4595 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4597 Can be overridden by passing C<< { where => undef } >> as an attribute
4600 For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
4606 Set to 1 to cache search results. This prevents extra SQL queries if you
4607 revisit rows in your ResultSet:
4609 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4611 while( my $artist = $resultset->next ) {
4615 $rs->first; # without cache, this would issue a query
4617 By default, searches are not cached.
4619 For more examples of using these attributes, see
4620 L<DBIx::Class::Manual::Cookbook>.
4626 =item Value: ( 'update' | 'shared' | \$scalar )
4630 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4631 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4636 DBIx::Class supports arbitrary related data prefetching from multiple related
4637 sources. Any combination of relationship types and column sets are supported.
4638 If L<collapsing|/collapse> is requested, there is an additional requirement of
4639 selecting enough data to make every individual object uniquely identifiable.
4641 Here are some more involved examples, based on the following relationship map:
4644 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4645 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4646 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4648 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4650 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4654 my $rs = $schema->resultset('Tag')->search(
4663 The initial search results in SQL like the following:
4665 SELECT tag.*, cd.*, artist.* FROM tag
4666 JOIN cd ON tag.cd = cd.cdid
4667 JOIN artist ON cd.artist = artist.artistid
4669 L<DBIx::Class> has no need to go back to the database when we access the
4670 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4673 Simple prefetches will be joined automatically, so there is no need
4674 for a C<join> attribute in the above search.
4676 The L</prefetch> attribute can be used with any of the relationship types
4677 and multiple prefetches can be specified together. Below is a more complex
4678 example that prefetches a CD's artist, its liner notes (if present),
4679 the cover image, the tracks on that CD, and the guests on those
4682 my $rs = $schema->resultset('CD')->search(
4686 { artist => 'record_label'}, # belongs_to => belongs_to
4687 'liner_note', # might_have
4688 'cover_image', # has_one
4689 { tracks => 'guests' }, # has_many => has_many
4694 This will produce SQL like the following:
4696 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4700 ON artist.artistid = me.artistid
4701 JOIN record_label record_label
4702 ON record_label.labelid = artist.labelid
4703 LEFT JOIN track tracks
4704 ON tracks.cdid = me.cdid
4705 LEFT JOIN guest guests
4706 ON guests.trackid = track.trackid
4707 LEFT JOIN liner_notes liner_note
4708 ON liner_note.cdid = me.cdid
4709 JOIN cd_artwork cover_image
4710 ON cover_image.cdid = me.cdid
4713 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4714 C<tracks>, and C<guests> of the CD will all be available through the
4715 relationship accessors without the need for additional queries to the
4720 Prefetch does a lot of deep magic. As such, it may not behave exactly
4721 as you might expect.
4727 Prefetch uses the L</cache> to populate the prefetched relationships. This
4728 may or may not be what you want.
4732 If you specify a condition on a prefetched relationship, ONLY those
4733 rows that match the prefetched condition will be fetched into that relationship.
4734 This means that adding prefetch to a search() B<may alter> what is returned by
4735 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4737 my $artist_rs = $schema->resultset('Artist')->search({
4743 my $count = $artist_rs->first->cds->count;
4745 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4747 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4749 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4751 That cmp_ok() may or may not pass depending on the datasets involved. In other
4752 words the C<WHERE> condition would apply to the entire dataset, just like
4753 it would in regular SQL. If you want to add a condition only to the "right side"
4754 of a C<LEFT JOIN> - consider declaring and using a L<relationship with a custom
4755 condition|DBIx::Class::Relationship::Base/condition>
4759 =head1 DBIC BIND VALUES
4761 Because DBIC may need more information to bind values than just the column name
4762 and value itself, it uses a special format for both passing and receiving bind
4763 values. Each bind value should be composed of an arrayref of
4764 C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
4770 If present (in any form), this is what is being passed directly to bind_param.
4771 Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
4772 a single numerical type, while DBD::Pg takes a hashref if bind options.)
4774 If this is specified, all other bind options described below are ignored.
4778 If present, this is used to infer the actual bind attribute by passing to
4779 C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
4780 "data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
4782 Note that the data type is somewhat freeform (hence the sqlt_ prefix);
4783 currently drivers are expected to "Do the Right Thing" when given a common
4784 datatype name. (Not ideal, but that's what we got at this point.)
4788 Currently used to correctly allocate buffers for bind_param_inout().
4789 Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
4790 or to a sensible value based on the "data_type".
4794 Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
4795 explicitly specified they are never overridden). Also used by some weird DBDs,
4796 where the column name should be available at bind_param time (e.g. Oracle).
4800 For backwards compatibility and convenience, the following shortcuts are
4803 [ $name => $val ] === [ { dbic_colname => $name }, $val ]
4804 [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
4805 [ undef, $val ] === [ {}, $val ]
4806 $val === [ {}, $val ]
4808 =head1 AUTHOR AND CONTRIBUTORS
4810 See L<AUTHOR|DBIx::Class/AUTHOR> and L<CONTRIBUTORS|DBIx::Class/CONTRIBUTORS> in DBIx::Class
4814 You may distribute this code under the same terms as Perl itself.