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 == @_;
825 @{$call_cond}{@c_cols} = @_;
828 # process relationship data if any
829 for my $key (keys %$call_cond) {
831 length ref($call_cond->{$key})
833 my $relinfo = $rsrc->relationship_info($key)
835 # implicitly skip has_many's (likely MC)
836 (ref (my $val = delete $call_cond->{$key}) ne 'ARRAY' )
838 my ($rel_cond, $crosstable) = $rsrc->_resolve_condition(
839 $relinfo->{cond}, $val, $key, $key
842 $self->throw_exception("Complex condition via relationship '$key' is unsupported in find()")
843 if $crosstable or ref($rel_cond) ne 'HASH';
845 # supplement condition
846 # relationship conditions take precedence (?)
847 @{$call_cond}{keys %$rel_cond} = values %$rel_cond;
851 # add-in the resultset condition if any
852 ($call_cond) = $self->_merge_with_rscond($call_cond);
854 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
856 if (defined $constraint_name) {
857 $final_cond = $self->_qualify_cond_columns (
859 $self->_build_unique_cond (
867 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
868 # This means that we got here after a merger of relationship conditions
869 # in ::Relationship::Base::search_related (the row method), and furthermore
870 # the relationship is of the 'single' type. This means that the condition
871 # provided by the relationship (already attached to $self) is sufficient,
872 # as there can be only one row in the database that would satisfy the
876 # no key was specified - fall down to heuristics mode:
877 # run through all unique queries registered on the resultset, and
878 # 'OR' all qualifying queries together
879 my (@unique_queries, %seen_column_combinations);
880 for my $c_name ($rsrc->unique_constraint_names) {
881 next if $seen_column_combinations{
882 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
885 push @unique_queries, try {
886 $self->_build_unique_cond ($c_name, $call_cond, 'croak_on_nulls')
890 $final_cond = @unique_queries
891 ? [ map { $self->_qualify_cond_columns($_, $alias) } @unique_queries ]
892 : $self->_non_unique_find_fallback ($call_cond, $attrs)
896 # Run the query, passing the result_class since it should propagate for find
897 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
898 if ($rs->_resolved_attrs->{collapse}) {
900 carp "Query returned more than one row" if $rs->next;
908 # This is a stop-gap method as agreed during the discussion on find() cleanup:
909 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
911 # It is invoked when find() is called in legacy-mode with insufficiently-unique
912 # condition. It is provided for overrides until a saner way forward is devised
914 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
915 # the road. Please adjust your tests accordingly to catch this situation early
916 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
918 # The method will not be removed without an adequately complete replacement
919 # for strict-mode enforcement
920 sub _non_unique_find_fallback {
921 my ($self, $cond, $attrs) = @_;
923 return $self->_qualify_cond_columns(
925 exists $attrs->{alias}
927 : $self->{attrs}{alias}
932 sub _qualify_cond_columns {
933 my ($self, $cond, $alias) = @_;
935 my %aliased = %$cond;
936 for (keys %aliased) {
937 $aliased{"$alias.$_"} = delete $aliased{$_}
944 sub _build_unique_cond {
945 my ($self, $constraint_name, $final_cond, $croak_on_null) = @_;
947 my @c_cols = $self->result_source->unique_constraint_columns($constraint_name);
949 # trim out everything not in $columns
950 $final_cond = { map {
951 exists $final_cond->{$_}
952 ? ( $_ => $final_cond->{$_} )
956 if (my @missing = grep
957 { ! ($croak_on_null ? defined $final_cond->{$_} : exists $final_cond->{$_}) }
960 $self->throw_exception( sprintf ( "Unable to satisfy requested constraint '%s', no values for column(s): %s",
962 join (', ', map { "'$_'" } @missing),
969 !$ENV{DBIC_NULLABLE_KEY_NOWARN}
971 my @undefs = sort grep { ! defined $final_cond->{$_} } (keys %$final_cond)
973 carp_unique ( sprintf (
974 "NULL/undef values supplied for requested unique constraint '%s' (NULL "
975 . 'values in column(s): %s). This is almost certainly not what you wanted, '
976 . 'though you can set DBIC_NULLABLE_KEY_NOWARN to disable this warning.',
978 join (', ', map { "'$_'" } @undefs),
985 =head2 search_related
989 =item Arguments: $rel_name, $cond?, L<\%attrs?|/ATTRIBUTES>
991 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
995 $new_rs = $cd_rs->search_related('artist', {
999 Searches the specified relationship, optionally specifying a condition and
1000 attributes for matching records. See L</ATTRIBUTES> for more information.
1002 In list context, C<< ->all() >> is called implicitly on the resultset, thus
1003 returning a list of result objects instead. To avoid that, use L</search_related_rs>.
1005 See also L</search_related_rs>.
1009 sub search_related {
1010 return shift->related_resultset(shift)->search(@_);
1013 =head2 search_related_rs
1015 This method works exactly the same as search_related, except that
1016 it guarantees a resultset, even in list context.
1020 sub search_related_rs {
1021 return shift->related_resultset(shift)->search_rs(@_);
1028 =item Arguments: none
1030 =item Return Value: L<$cursor|DBIx::Class::Cursor>
1034 Returns a storage-driven cursor to the given resultset. See
1035 L<DBIx::Class::Cursor> for more information.
1042 return $self->{cursor} ||= do {
1043 my $attrs = $self->_resolved_attrs;
1044 $self->result_source->storage->select(
1045 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
1054 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1056 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1060 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1062 Inflates the first result without creating a cursor if the resultset has
1063 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1066 While this method can take an optional search condition (just like L</search>)
1067 being a fast-code-path it does not recognize search attributes. If you need to
1068 add extra joins or similar, call L</search> and then chain-call L</single> on the
1069 L<DBIx::Class::ResultSet> returned.
1075 As of 0.08100, this method enforces the assumption that the preceding
1076 query returns only one row. If more than one row is returned, you will receive
1079 Query returned more than one row
1081 In this case, you should be using L</next> or L</find> instead, or if you really
1082 know what you are doing, use the L</rows> attribute to explicitly limit the size
1085 This method will also throw an exception if it is called on a resultset prefetching
1086 has_many, as such a prefetch implies fetching multiple rows from the database in
1087 order to assemble the resulting object.
1094 my ($self, $where) = @_;
1096 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1099 my $attrs = { %{$self->_resolved_attrs} };
1101 $self->throw_exception(
1102 'single() can not be used on resultsets collapsing a has_many. Use find( \%cond ) or next() instead'
1103 ) if $attrs->{collapse};
1106 if (defined $attrs->{where}) {
1109 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1110 $where, delete $attrs->{where} ]
1113 $attrs->{where} = $where;
1117 my $data = [ $self->result_source->storage->select_single(
1118 $attrs->{from}, $attrs->{select},
1119 $attrs->{where}, $attrs
1122 return undef unless @$data;
1123 $self->{_stashed_rows} = [ $data ];
1124 $self->_construct_results->[0];
1131 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1133 =item Return Value: L<$resultsetcolumn|DBIx::Class::ResultSetColumn>
1137 my $max_length = $rs->get_column('length')->max;
1139 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1144 my ($self, $column) = @_;
1145 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
1153 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1155 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1159 # WHERE title LIKE '%blue%'
1160 $cd_rs = $rs->search_like({ title => '%blue%'});
1162 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1163 that this is simply a convenience method retained for ex Class::DBI users.
1164 You most likely want to use L</search> with specific operators.
1166 For more information, see L<DBIx::Class::Manual::Cookbook>.
1168 This method is deprecated and will be removed in 0.09. Use L</search()>
1169 instead. An example conversion is:
1171 ->search_like({ foo => 'bar' });
1175 ->search({ foo => { like => 'bar' } });
1182 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1183 .' Instead use ->search({ x => { -like => "y%" } })'
1184 .' (note the outer pair of {}s - they are important!)'
1186 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1187 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1188 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1189 return $class->search($query, { %$attrs });
1196 =item Arguments: $first, $last
1198 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1202 Returns a resultset or object list representing a subset of elements from the
1203 resultset slice is called on. Indexes are from 0, i.e., to get the first
1204 three records, call:
1206 my ($one, $two, $three) = $rs->slice(0, 2);
1211 my ($self, $min, $max) = @_;
1212 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1213 $attrs->{offset} = $self->{attrs}{offset} || 0;
1214 $attrs->{offset} += $min;
1215 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1216 return $self->search(undef, $attrs);
1223 =item Arguments: none
1225 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1229 Returns the next element in the resultset (C<undef> is there is none).
1231 Can be used to efficiently iterate over records in the resultset:
1233 my $rs = $schema->resultset('CD')->search;
1234 while (my $cd = $rs->next) {
1238 Note that you need to store the resultset object, and call C<next> on it.
1239 Calling C<< resultset('Table')->next >> repeatedly will always return the
1240 first record from the resultset.
1247 if (my $cache = $self->get_cache) {
1248 $self->{all_cache_position} ||= 0;
1249 return $cache->[$self->{all_cache_position}++];
1252 if ($self->{attrs}{cache}) {
1253 delete $self->{pager};
1254 $self->{all_cache_position} = 1;
1255 return ($self->all)[0];
1258 return shift(@{$self->{_stashed_results}}) if @{ $self->{_stashed_results}||[] };
1260 $self->{_stashed_results} = $self->_construct_results
1263 return shift @{$self->{_stashed_results}};
1266 # Constructs as many results as it can in one pass while respecting
1267 # cursor laziness. Several modes of operation:
1269 # * Always builds everything present in @{$self->{_stashed_rows}}
1270 # * If called with $fetch_all true - pulls everything off the cursor and
1271 # builds all result structures (or objects) in one pass
1272 # * If $self->_resolved_attrs->{collapse} is true, checks the order_by
1273 # and if the resultset is ordered properly by the left side:
1274 # * Fetches stuff off the cursor until the "master object" changes,
1275 # and saves the last extra row (if any) in @{$self->{_stashed_rows}}
1277 # * Just fetches, and collapses/constructs everything as if $fetch_all
1278 # was requested (there is no other way to collapse except for an
1280 # * If no collapse is requested - just get the next row, construct and
1282 sub _construct_results {
1283 my ($self, $fetch_all) = @_;
1285 my $rsrc = $self->result_source;
1286 my $attrs = $self->_resolved_attrs;
1291 ! $attrs->{order_by}
1295 my @pcols = $rsrc->primary_columns
1297 # default order for collapsing unless the user asked for something
1298 $attrs->{order_by} = [ map { join '.', $attrs->{alias}, $_} @pcols ];
1299 $attrs->{_ordered_for_collapse} = 1;
1300 $attrs->{_order_is_artificial} = 1;
1303 # this will be used as both initial raw-row collector AND as a RV of
1304 # _construct_results. Not regrowing the array twice matters a lot...
1305 # a surprising amount actually
1306 my $rows = delete $self->{_stashed_rows};
1308 my $cursor; # we may not need one at all
1310 my $did_fetch_all = $fetch_all;
1313 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1314 $rows = [ ($rows ? @$rows : ()), $self->cursor->all ];
1316 elsif( $attrs->{collapse} ) {
1318 # a cursor will need to be closed over in case of collapse
1319 $cursor = $self->cursor;
1321 $attrs->{_ordered_for_collapse} = (
1327 ->_extract_colinfo_of_stable_main_source_order_by_portion($attrs)
1329 ) unless defined $attrs->{_ordered_for_collapse};
1331 if (! $attrs->{_ordered_for_collapse}) {
1334 # instead of looping over ->next, use ->all in stealth mode
1335 # *without* calling a ->reset afterwards
1336 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1337 if (! $cursor->{_done}) {
1338 $rows = [ ($rows ? @$rows : ()), $cursor->all ];
1339 $cursor->{_done} = 1;
1344 if (! $did_fetch_all and ! @{$rows||[]} ) {
1345 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1346 $cursor ||= $self->cursor;
1347 if (scalar (my @r = $cursor->next) ) {
1352 return undef unless @{$rows||[]};
1354 # sanity check - people are too clever for their own good
1355 if ($attrs->{collapse} and my $aliastypes = $attrs->{_last_sqlmaker_alias_map} ) {
1357 my $multiplied_selectors;
1358 for my $sel_alias ( grep { $_ ne $attrs->{alias} } keys %{ $aliastypes->{selecting} } ) {
1360 $aliastypes->{multiplying}{$sel_alias}
1362 $aliastypes->{premultiplied}{$sel_alias}
1364 $multiplied_selectors->{$_} = 1 for values %{$aliastypes->{selecting}{$sel_alias}{-seen_columns}}
1368 for my $i (0 .. $#{$attrs->{as}} ) {
1369 my $sel = $attrs->{select}[$i];
1371 if (ref $sel eq 'SCALAR') {
1374 elsif( ref $sel eq 'REF' and ref $$sel eq 'ARRAY' ) {
1378 $self->throw_exception(
1379 'Result collapse not possible - selection from a has_many source redirected to the main object'
1380 ) if ($multiplied_selectors->{$sel} and $attrs->{as}[$i] !~ /\./);
1384 # hotspot - skip the setter
1385 my $res_class = $self->_result_class;
1387 my $inflator_cref = $self->{_result_inflator}{cref} ||= do {
1388 $res_class->can ('inflate_result')
1389 or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
1392 my $infmap = $attrs->{as};
1394 $self->{_result_inflator}{is_core_row} = ( (
1397 ( \&DBIx::Class::Row::inflate_result || die "No ::Row::inflate_result() - can't happen" )
1398 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_core_row};
1400 $self->{_result_inflator}{is_hri} = ( (
1401 ! $self->{_result_inflator}{is_core_row}
1404 require DBIx::Class::ResultClass::HashRefInflator
1406 DBIx::Class::ResultClass::HashRefInflator->can('inflate_result')
1408 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_hri};
1411 if ($attrs->{_simple_passthrough_construction}) {
1412 # construct a much simpler array->hash folder for the one-table HRI cases right here
1413 if ($self->{_result_inflator}{is_hri}) {
1414 for my $r (@$rows) {
1415 $r = { map { $infmap->[$_] => $r->[$_] } 0..$#$infmap };
1418 # FIXME SUBOPTIMAL this is a very very very hot spot
1419 # while rather optimal we can *still* do much better, by
1420 # building a smarter Row::inflate_result(), and
1421 # switch to feeding it data via a much leaner interface
1423 # crude unscientific benchmarking indicated the shortcut eval is not worth it for
1424 # this particular resultset size
1425 elsif ( $self->{_result_inflator}{is_core_row} and @$rows < 60 ) {
1426 for my $r (@$rows) {
1427 $r = $inflator_cref->($res_class, $rsrc, { map { $infmap->[$_] => $r->[$_] } (0..$#$infmap) } );
1432 ( $self->{_result_inflator}{is_core_row}
1433 ? '$_ = $inflator_cref->($res_class, $rsrc, { %s }) for @$rows'
1434 # a custom inflator may be a multiplier/reductor - put it in direct list ctx
1435 : '@$rows = map { $inflator_cref->($res_class, $rsrc, { %s } ) } @$rows'
1437 ( join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap ) )
1443 $self->{_result_inflator}{is_hri} ? 'hri'
1444 : $self->{_result_inflator}{is_core_row} ? 'classic_pruning'
1445 : 'classic_nonpruning'
1448 # $args and $attrs to _mk_row_parser are separated to delineate what is
1449 # core collapser stuff and what is dbic $rs specific
1450 @{$self->{_row_parser}{$parser_type}}{qw(cref nullcheck)} = $rsrc->_mk_row_parser({
1452 inflate_map => $infmap,
1453 collapse => $attrs->{collapse},
1454 premultiplied => $attrs->{_main_source_premultiplied},
1455 hri_style => $self->{_result_inflator}{is_hri},
1456 prune_null_branches => $self->{_result_inflator}{is_hri} || $self->{_result_inflator}{is_core_row},
1457 }, $attrs) unless $self->{_row_parser}{$parser_type}{cref};
1459 # column_info metadata historically hasn't been too reliable.
1460 # We need to start fixing this somehow (the collapse resolver
1461 # can't work without it). Add an explicit check for the *main*
1462 # result, hopefully this will gradually weed out such errors
1464 # FIXME - this is a temporary kludge that reduces performance
1465 # It is however necessary for the time being
1466 my ($unrolled_non_null_cols_to_check, $err);
1468 if (my $check_non_null_cols = $self->{_row_parser}{$parser_type}{nullcheck} ) {
1471 'Collapse aborted due to invalid ResultSource metadata - the following '
1472 . 'selections are declared non-nullable but NULLs were retrieved: '
1476 COL: for my $i (@$check_non_null_cols) {
1477 ! defined $_->[$i] and push @violating_idx, $i and next COL for @$rows;
1480 $self->throw_exception( $err . join (', ', map { "'$infmap->[$_]'" } @violating_idx ) )
1483 $unrolled_non_null_cols_to_check = join (',', @$check_non_null_cols);
1487 ($did_fetch_all or ! $attrs->{collapse}) ? undef
1488 : defined $unrolled_non_null_cols_to_check ? eval sprintf <<'EOS', $unrolled_non_null_cols_to_check
1490 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1491 my @r = $cursor->next or return;
1492 if (my @violating_idx = grep { ! defined $r[$_] } (%s) ) {
1493 $self->throw_exception( $err . join (', ', map { "'$infmap->[$_]'" } @violating_idx ) )
1499 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1500 my @r = $cursor->next or return;
1505 $self->{_row_parser}{$parser_type}{cref}->(
1507 $next_cref ? ( $next_cref, $self->{_stashed_rows} = [] ) : (),
1510 # simple in-place substitution, does not regrow $rows
1511 if ($self->{_result_inflator}{is_core_row}) {
1512 $_ = $inflator_cref->($res_class, $rsrc, @$_) for @$rows
1514 # Special-case multi-object HRI - there is no $inflator_cref pass at all
1515 elsif ( ! $self->{_result_inflator}{is_hri} ) {
1516 # the inflator may be a multiplier/reductor - put it in list ctx
1517 @$rows = map { $inflator_cref->($res_class, $rsrc, @$_) } @$rows;
1521 # The @$rows check seems odd at first - why wouldn't we want to warn
1522 # regardless? The issue is things like find() etc, where the user
1523 # *knows* only one result will come back. In these cases the ->all
1524 # is not a pessimization, but rather something we actually want
1526 'Unable to properly collapse has_many results in iterator mode due '
1527 . 'to order criteria - performed an eager cursor slurp underneath. '
1528 . 'Consider using ->all() instead'
1529 ) if ( ! $fetch_all and @$rows > 1 );
1534 =head2 result_source
1538 =item Arguments: L<$result_source?|DBIx::Class::ResultSource>
1540 =item Return Value: L<$result_source|DBIx::Class::ResultSource>
1544 An accessor for the primary ResultSource object from which this ResultSet
1551 =item Arguments: $result_class?
1553 =item Return Value: $result_class
1557 An accessor for the class to use when creating result objects. Defaults to
1558 C<< result_source->result_class >> - which in most cases is the name of the
1559 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1561 Note that changing the result_class will also remove any components
1562 that were originally loaded in the source class via
1563 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1564 in the original source class will not run.
1569 my ($self, $result_class) = @_;
1570 if ($result_class) {
1572 # don't fire this for an object
1573 $self->ensure_class_loaded($result_class)
1574 unless ref($result_class);
1576 if ($self->get_cache) {
1577 carp_unique('Changing the result_class of a ResultSet instance with cached results is a noop - the cache contents will not be altered');
1579 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1580 elsif ($self->{cursor} && $self->{cursor}{_pos}) {
1581 $self->throw_exception('Changing the result_class of a ResultSet instance with an active cursor is not supported');
1584 $self->_result_class($result_class);
1586 delete $self->{_result_inflator};
1588 $self->_result_class;
1595 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1597 =item Return Value: $count
1601 Performs an SQL C<COUNT> with the same query as the resultset was built
1602 with to find the number of elements. Passing arguments is equivalent to
1603 C<< $rs->search ($cond, \%attrs)->count >>
1609 return $self->search(@_)->count if @_ and defined $_[0];
1610 return scalar @{ $self->get_cache } if $self->get_cache;
1612 my $attrs = { %{ $self->_resolved_attrs } };
1614 # this is a little optimization - it is faster to do the limit
1615 # adjustments in software, instead of a subquery
1616 my ($rows, $offset) = delete @{$attrs}{qw/rows offset/};
1619 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1620 $crs = $self->_count_subq_rs ($attrs);
1623 $crs = $self->_count_rs ($attrs);
1625 my $count = $crs->next;
1627 $count -= $offset if $offset;
1628 $count = $rows if $rows and $rows < $count;
1629 $count = 0 if ($count < 0);
1638 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1640 =item Return Value: L<$count_rs|DBIx::Class::ResultSetColumn>
1644 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1645 This can be very handy for subqueries:
1647 ->search( { amount => $some_rs->count_rs->as_query } )
1649 As with regular resultsets the SQL query will be executed only after
1650 the resultset is accessed via L</next> or L</all>. That would return
1651 the same single value obtainable via L</count>.
1657 return $self->search(@_)->count_rs if @_;
1659 # this may look like a lack of abstraction (count() does about the same)
1660 # but in fact an _rs *must* use a subquery for the limits, as the
1661 # software based limiting can not be ported if this $rs is to be used
1662 # in a subquery itself (i.e. ->as_query)
1663 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1664 return $self->_count_subq_rs($self->{_attrs});
1667 return $self->_count_rs($self->{_attrs});
1672 # returns a ResultSetColumn object tied to the count query
1675 my ($self, $attrs) = @_;
1677 my $rsrc = $self->result_source;
1679 my $tmp_attrs = { %$attrs };
1680 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1681 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1683 # overwrite the selector (supplied by the storage)
1684 $rsrc->resultset_class->new($rsrc, {
1686 select => $rsrc->storage->_count_select ($rsrc, $attrs),
1688 })->get_column ('count');
1692 # same as above but uses a subquery
1694 sub _count_subq_rs {
1695 my ($self, $attrs) = @_;
1697 my $rsrc = $self->result_source;
1699 my $sub_attrs = { %$attrs };
1700 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1701 delete @{$sub_attrs}{qw/collapse columns as select order_by for/};
1703 # if we multi-prefetch we group_by something unique, as this is what we would
1704 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1705 if ( $attrs->{collapse} ) {
1706 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1707 $rsrc->_identifying_column_set || $self->throw_exception(
1708 'Unable to construct a unique group_by criteria properly collapsing the '
1709 . 'has_many prefetch before count()'
1714 # Calculate subquery selector
1715 if (my $g = $sub_attrs->{group_by}) {
1717 my $sql_maker = $rsrc->storage->sql_maker;
1719 # necessary as the group_by may refer to aliased functions
1721 for my $sel (@{$attrs->{select}}) {
1722 $sel_index->{$sel->{-as}} = $sel
1723 if (ref $sel eq 'HASH' and $sel->{-as});
1726 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1727 # also look for named aggregates referred in the having clause
1728 # having often contains scalarrefs - thus parse it out entirely
1730 if ($attrs->{having}) {
1731 local $sql_maker->{having_bind};
1732 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1733 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1734 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1735 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1736 # if we don't unset it we screw up retarded but unfortunately working
1737 # 'MAX(foo.bar)' => { '>', 3 }
1738 $sql_maker->{name_sep} = '';
1741 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1743 my $having_sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1746 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1747 # and if all fails for an utterly naive quoted scalar-with-function
1748 while ($having_sql =~ /
1749 $rquote $sep $lquote (.+?) $rquote
1751 [\s,] \w+ \. (\w+) [\s,]
1753 [\s,] $lquote (.+?) $rquote [\s,]
1755 my $part = $1 || $2 || $3; # one of them matched if we got here
1756 unless ($seen_having{$part}++) {
1763 my $colpiece = $sel_index->{$_} || $_;
1765 # unqualify join-based group_by's. Arcane but possible query
1766 # also horrible horrible hack to alias a column (not a func.)
1767 # (probably need to introduce SQLA syntax)
1768 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1771 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1773 push @{$sub_attrs->{select}}, $colpiece;
1777 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1778 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1781 return $rsrc->resultset_class
1782 ->new ($rsrc, $sub_attrs)
1784 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1785 ->get_column ('count');
1789 =head2 count_literal
1791 B<CAVEAT>: C<count_literal> is provided for Class::DBI compatibility and
1792 should only be used in that context. See L</search_literal> for further info.
1796 =item Arguments: $sql_fragment, @standalone_bind_values
1798 =item Return Value: $count
1802 Counts the results in a literal query. Equivalent to calling L</search_literal>
1803 with the passed arguments, then L</count>.
1807 sub count_literal { shift->search_literal(@_)->count; }
1813 =item Arguments: none
1815 =item Return Value: L<@result_objs|DBIx::Class::Manual::ResultClass>
1819 Returns all elements in the resultset.
1826 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1829 delete @{$self}{qw/_stashed_rows _stashed_results/};
1831 if (my $c = $self->get_cache) {
1835 $self->cursor->reset;
1837 my $objs = $self->_construct_results('fetch_all') || [];
1839 $self->set_cache($objs) if $self->{attrs}{cache};
1848 =item Arguments: none
1850 =item Return Value: $self
1854 Resets the resultset's cursor, so you can iterate through the elements again.
1855 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1863 delete @{$self}{qw/_stashed_rows _stashed_results/};
1864 $self->{all_cache_position} = 0;
1865 $self->cursor->reset;
1873 =item Arguments: none
1875 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1879 L<Resets|/reset> the resultset (causing a fresh query to storage) and returns
1880 an object for the first result (or C<undef> if the resultset is empty).
1885 return $_[0]->reset->next;
1891 # Determines whether and what type of subquery is required for the $rs operation.
1892 # If grouping is necessary either supplies its own, or verifies the current one
1893 # After all is done delegates to the proper storage method.
1895 sub _rs_update_delete {
1896 my ($self, $op, $values) = @_;
1898 my $rsrc = $self->result_source;
1899 my $storage = $rsrc->schema->storage;
1901 my $attrs = { %{$self->_resolved_attrs} };
1903 my $join_classifications;
1904 my ($existing_group_by) = delete @{$attrs}{qw(group_by _grouped_by_distinct)};
1906 # do we need a subquery for any reason?
1908 defined $existing_group_by
1910 # if {from} is unparseable wrap a subq
1911 ref($attrs->{from}) ne 'ARRAY'
1913 # limits call for a subq
1914 $self->_has_resolved_attr(qw/rows offset/)
1917 # simplify the joinmap, so we can further decide if a subq is necessary
1918 if (!$needs_subq and @{$attrs->{from}} > 1) {
1920 ($attrs->{from}, $join_classifications) =
1921 $storage->_prune_unused_joins ($attrs);
1923 # any non-pruneable non-local restricting joins imply subq
1924 $needs_subq = defined List::Util::first { $_ ne $attrs->{alias} } keys %{ $join_classifications->{restricting} || {} };
1927 # check if the head is composite (by now all joins are thrown out unless $needs_subq)
1929 (ref $attrs->{from}[0]) ne 'HASH'
1931 ref $attrs->{from}[0]{ $attrs->{from}[0]{-alias} }
1935 # do we need anything like a subquery?
1936 if (! $needs_subq) {
1937 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1938 # a condition containing 'me' or other table prefixes will not work
1939 # at all. Tell SQLMaker to dequalify idents via a gross hack.
1941 my $sqla = $rsrc->storage->sql_maker;
1942 local $sqla->{_dequalify_idents} = 1;
1943 \[ $sqla->_recurse_where($self->{cond}) ];
1947 # we got this far - means it is time to wrap a subquery
1948 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1950 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1956 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1957 delete $attrs->{$_} for qw/select as collapse/;
1958 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1960 # this will be consumed by the pruner waaaaay down the stack
1961 $attrs->{_force_prune_multiplying_joins} = 1;
1963 my $subrs = (ref $self)->new($rsrc, $attrs);
1965 if (@$idcols == 1) {
1966 $cond = { $idcols->[0] => { -in => $subrs->as_query } };
1968 elsif ($storage->_use_multicolumn_in) {
1969 # no syntax for calling this properly yet
1970 # !!! EXPERIMENTAL API !!! WILL CHANGE !!!
1971 $cond = $storage->sql_maker->_where_op_multicolumn_in (
1972 $idcols, # how do I convey a list of idents...? can binds reside on lhs?
1977 # if all else fails - get all primary keys and operate over a ORed set
1978 # wrap in a transaction for consistency
1979 # this is where the group_by/multiplication starts to matter
1983 # we do not need to check pre-multipliers, since if the premulti is there, its
1984 # parent (who is multi) will be there too
1985 keys %{ $join_classifications->{multiplying} || {} }
1987 # make sure if there is a supplied group_by it matches the columns compiled above
1988 # perfectly. Anything else can not be sanely executed on most databases so croak
1989 # right then and there
1990 if ($existing_group_by) {
1991 my @current_group_by = map
1992 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1997 join ("\x00", sort @current_group_by)
1999 join ("\x00", sort @{$attrs->{columns}} )
2001 $self->throw_exception (
2002 "You have just attempted a $op operation on a resultset which does group_by"
2003 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
2004 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
2005 . ' kind of queries. Please retry the operation with a modified group_by or'
2006 . ' without using one at all.'
2011 $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
2014 $guard = $storage->txn_scope_guard;
2016 for my $row ($subrs->cursor->all) {
2018 { $idcols->[$_] => $row->[$_] }
2025 my $res = $cond ? $storage->$op (
2027 $op eq 'update' ? $values : (),
2031 $guard->commit if $guard;
2040 =item Arguments: \%values
2042 =item Return Value: $underlying_storage_rv
2046 Sets the specified columns in the resultset to the supplied values in a
2047 single query. Note that this will not run any accessor/set_column/update
2048 triggers, nor will it update any result object instances derived from this
2049 resultset (this includes the contents of the L<resultset cache|/set_cache>
2050 if any). See L</update_all> if you need to execute any on-update
2051 triggers or cascades defined either by you or a
2052 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2054 The return value is a pass through of what the underlying
2055 storage backend returned, and may vary. See L<DBI/execute> for the most
2060 Note that L</update> does not process/deflate any of the values passed in.
2061 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
2062 ensure manually that any value passed to this method will stringify to
2063 something the RDBMS knows how to deal with. A notable example is the
2064 handling of L<DateTime> objects, for more info see:
2065 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
2070 my ($self, $values) = @_;
2071 $self->throw_exception('Values for update must be a hash')
2072 unless ref $values eq 'HASH';
2074 return $self->_rs_update_delete ('update', $values);
2081 =item Arguments: \%values
2083 =item Return Value: 1
2087 Fetches all objects and updates them one at a time via
2088 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
2089 triggers, while L</update> will not.
2094 my ($self, $values) = @_;
2095 $self->throw_exception('Values for update_all must be a hash')
2096 unless ref $values eq 'HASH';
2098 my $guard = $self->result_source->schema->txn_scope_guard;
2099 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
2108 =item Arguments: none
2110 =item Return Value: $underlying_storage_rv
2114 Deletes the rows matching this resultset in a single query. Note that this
2115 will not run any delete triggers, nor will it alter the
2116 L<in_storage|DBIx::Class::Row/in_storage> status of any result object instances
2117 derived from this resultset (this includes the contents of the
2118 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
2119 execute any on-delete triggers or cascades defined either by you or a
2120 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2122 The return value is a pass through of what the underlying storage backend
2123 returned, and may vary. See L<DBI/execute> for the most common case.
2129 $self->throw_exception('delete does not accept any arguments')
2132 return $self->_rs_update_delete ('delete');
2139 =item Arguments: none
2141 =item Return Value: 1
2145 Fetches all objects and deletes them one at a time via
2146 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2147 triggers, while L</delete> will not.
2153 $self->throw_exception('delete_all does not accept any arguments')
2156 my $guard = $self->result_source->schema->txn_scope_guard;
2157 $_->delete for $self->all;
2166 =item Arguments: [ \@column_list, \@row_values+ ] | [ \%col_data+ ]
2168 =item Return Value: L<\@result_objects|DBIx::Class::Manual::ResultClass> (scalar context) | L<@result_objects|DBIx::Class::Manual::ResultClass> (list context)
2172 Accepts either an arrayref of hashrefs or alternatively an arrayref of
2179 The context of this method call has an important effect on what is
2180 submitted to storage. In void context data is fed directly to fastpath
2181 insertion routines provided by the underlying storage (most often
2182 L<DBI/execute_for_fetch>), bypassing the L<new|DBIx::Class::Row/new> and
2183 L<insert|DBIx::Class::Row/insert> calls on the
2184 L<Result|DBIx::Class::Manual::ResultClass> class, including any
2185 augmentation of these methods provided by components. For example if you
2186 are using something like L<DBIx::Class::UUIDColumns> to create primary
2187 keys for you, you will find that your PKs are empty. In this case you
2188 will have to explicitly force scalar or list context in order to create
2193 In non-void (scalar or list) context, this method is simply a wrapper
2194 for L</create>. Depending on list or scalar context either a list of
2195 L<Result|DBIx::Class::Manual::ResultClass> objects or an arrayref
2196 containing these objects is returned.
2198 When supplying data in "arrayref of arrayrefs" invocation style, the
2199 first element should be a list of column names and each subsequent
2200 element should be a data value in the earlier specified column order.
2203 $schema->resultset("Artist")->populate([
2204 [ qw( artistid name ) ],
2205 [ 100, 'A Formally Unknown Singer' ],
2206 [ 101, 'A singer that jumped the shark two albums ago' ],
2207 [ 102, 'An actually cool singer' ],
2210 For the arrayref of hashrefs style each hashref should be a structure
2211 suitable for passing to L</create>. Multi-create is also permitted with
2214 $schema->resultset("Artist")->populate([
2215 { artistid => 4, name => 'Manufactured Crap', cds => [
2216 { title => 'My First CD', year => 2006 },
2217 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2220 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2221 { title => 'My parents sold me to a record company', year => 2005 },
2222 { title => 'Why Am I So Ugly?', year => 2006 },
2223 { title => 'I Got Surgery and am now Popular', year => 2007 }
2228 If you attempt a void-context multi-create as in the example above (each
2229 Artist also has the related list of CDs), and B<do not> supply the
2230 necessary autoinc foreign key information, this method will proxy to the
2231 less efficient L</create>, and then throw the Result objects away. In this
2232 case there are obviously no benefits to using this method over L</create>.
2241 # this is naive and just a quick check
2242 # the types will need to be checked more thoroughly when the
2243 # multi-source populate gets added
2244 if (ref $_[0] eq 'ARRAY') {
2245 return unless @{$_[0]};
2247 $data = $_[0] if (ref $_[0][0] eq 'HASH' or ref $_[0][0] eq 'ARRAY');
2250 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs')
2253 # FIXME - no cref handling
2254 # At this point assume either hashes or arrays
2256 if(defined wantarray) {
2259 $guard = $self->result_source->schema->storage->txn_scope_guard
2260 if ( @$data > 2 or ( @$data == 2 and ref $data->[0] eq 'ARRAY' ) );
2262 if (ref $data->[0] eq 'ARRAY') {
2264 { my $vals = $_; $self->new_result({ map { $data->[0][$_] => $vals->[$_] } 0..$#{$data->[0]} })->insert }
2265 @{$data}[1 .. $#$data]
2269 @results = map { $self->new_result($_)->insert } @$data;
2272 $guard->commit if $guard;
2273 return wantarray ? @results : \@results;
2276 # we have to deal with *possibly incomplete* related data
2277 # this means we have to walk the data structure twice
2278 # whether we want this or not
2279 # jnap, I hate you ;)
2280 my $rsrc = $self->result_source;
2281 my $rel_info = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2283 my ($colinfo, $colnames, $slices_with_rels);
2287 for my $i (0 .. $#$data) {
2289 my $current_slice_seen_rel_infos;
2291 ### Determine/Supplement collists
2292 ### BEWARE - This is a hot piece of code, a lot of weird idioms were used
2293 if( ref $data->[$i] eq 'ARRAY' ) {
2295 # positional(!) explicit column list
2298 $colinfo->{$data->[0][$_]} = { pos => $_, name => $data->[0][$_] } and push @$colnames, $data->[0][$_]
2299 for 0 .. $#{$data->[0]};
2306 for (values %$colinfo) {
2307 if ($_->{is_rel} ||= (
2308 $rel_info->{$_->{name}}
2311 ref $data->[$i][$_->{pos}] eq 'ARRAY'
2313 ref $data->[$i][$_->{pos}] eq 'HASH'
2315 ( defined blessed $data->[$i][$_->{pos}] and $data->[$i][$_->{pos}]->isa('DBIx::Class::Row') )
2321 # moar sanity check... sigh
2322 for ( ref $data->[$i][$_->{pos}] eq 'ARRAY' ? @{$data->[$i][$_->{pos}]} : $data->[$i][$_->{pos}] ) {
2323 if ( defined blessed $_ and $_->isa('DBIx::Class::Row' ) ) {
2324 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2325 return my $throwaway = $self->populate(@_);
2329 push @$current_slice_seen_rel_infos, $rel_info->{$_->{name}};
2334 if ($current_slice_seen_rel_infos) {
2335 push @$slices_with_rels, { map { $colnames->[$_] => $data->[$i][$_] } 0 .. $#$colnames };
2337 # this is needed further down to decide whether or not to fallback to create()
2338 $colinfo->{$colnames->[$_]}{seen_null} ||= ! defined $data->[$i][$_]
2339 for 0 .. $#$colnames;
2342 elsif( ref $data->[$i] eq 'HASH' ) {
2344 for ( sort keys %{$data->[$i]} ) {
2346 $colinfo->{$_} ||= do {
2348 $self->throw_exception("Column '$_' must be present in supplied explicit column list")
2349 if $data_start; # it will be 0 on AoH, 1 on AoA
2351 push @$colnames, $_;
2354 { pos => $#$colnames, name => $_ }
2357 if ($colinfo->{$_}{is_rel} ||= (
2361 ref $data->[$i]{$_} eq 'ARRAY'
2363 ref $data->[$i]{$_} eq 'HASH'
2365 ( defined blessed $data->[$i]{$_} and $data->[$i]{$_}->isa('DBIx::Class::Row') )
2371 # moar sanity check... sigh
2372 for ( ref $data->[$i]{$_} eq 'ARRAY' ? @{$data->[$i]{$_}} : $data->[$i]{$_} ) {
2373 if ( defined blessed $_ and $_->isa('DBIx::Class::Row' ) ) {
2374 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2375 return my $throwaway = $self->populate(@_);
2379 push @$current_slice_seen_rel_infos, $rel_info->{$_};
2383 if ($current_slice_seen_rel_infos) {
2384 push @$slices_with_rels, $data->[$i];
2386 # this is needed further down to decide whether or not to fallback to create()
2387 $colinfo->{$_}{seen_null} ||= ! defined $data->[$i]{$_}
2388 for keys %{$data->[$i]};
2392 $self->throw_exception('Unexpected populate() data structure member type: ' . ref $data->[$i] );
2396 { $_->{attrs}{is_depends_on} }
2397 @{ $current_slice_seen_rel_infos || [] }
2399 carp_unique("Fast-path populate() of belongs_to relationship data is not possible - falling back to regular create()");
2400 return my $throwaway = $self->populate(@_);
2404 if( $slices_with_rels ) {
2406 # need to exclude the rel "columns"
2407 $colnames = [ grep { ! $colinfo->{$_}{is_rel} } @$colnames ];
2409 # extra sanity check - ensure the main source is in fact identifiable
2410 # the localizing of nullability is insane, but oh well... the use-case is legit
2411 my $ci = $rsrc->columns_info($colnames);
2413 $ci->{$_} = { %{$ci->{$_}}, is_nullable => 0 }
2414 for grep { ! $colinfo->{$_}{seen_null} } keys %$ci;
2416 unless( $rsrc->_identifying_column_set($ci) ) {
2417 carp_unique("Fast-path populate() of non-uniquely identifiable rows with related data is not possible - falling back to regular create()");
2418 return my $throwaway = $self->populate(@_);
2422 ### inherit the data locked in the conditions of the resultset
2423 my ($rs_data) = $self->_merge_with_rscond({});
2424 delete @{$rs_data}{@$colnames}; # passed-in stuff takes precedence
2426 # if anything left - decompose rs_data
2428 if (keys %$rs_data) {
2429 push @$rs_data_vals, $rs_data->{$_}
2430 for sort keys %$rs_data;
2434 $guard = $rsrc->schema->storage->txn_scope_guard
2435 if $slices_with_rels;
2437 ### main source data
2438 # FIXME - need to switch entirely to a coderef-based thing,
2439 # so that large sets aren't copied several times... I think
2440 $rsrc->storage->insert_bulk(
2442 [ @$colnames, sort keys %$rs_data ],
2444 ref $data->[$_] eq 'ARRAY'
2446 $slices_with_rels ? [ @{$data->[$_]}[0..$#$colnames], @{$rs_data_vals||[]} ] # the collist changed
2447 : $rs_data_vals ? [ @{$data->[$_]}, @$rs_data_vals ]
2450 : [ @{$data->[$_]}{@$colnames}, @{$rs_data_vals||[]} ]
2451 } $data_start .. $#$data ],
2454 ### do the children relationships
2455 if ( $slices_with_rels ) {
2456 my @rels = grep { $colinfo->{$_}{is_rel} } keys %$colinfo
2457 or die 'wtf... please report a bug with DBIC_TRACE=1 output (stacktrace)';
2459 for my $sl (@$slices_with_rels) {
2461 my ($main_proto, $main_proto_rs);
2462 for my $rel (@rels) {
2463 next unless defined $sl->{$rel};
2467 (map { $_ => $sl->{$_} } @$colnames),
2470 unless (defined $colinfo->{$rel}{rs}) {
2472 $colinfo->{$rel}{rs} = $rsrc->related_source($rel)->resultset;
2474 $colinfo->{$rel}{fk_map} = { reverse %{ $rsrc->_resolve_relationship_condition(
2476 self_alias => "\xFE", # irrelevant
2477 foreign_alias => "\xFF", # irrelevant
2478 )->{identity_map} || {} } };
2482 $colinfo->{$rel}{rs}->search({ map # only so that we inherit them values properly, no actual search
2485 ( $main_proto_rs ||= $rsrc->resultset->search($main_proto) )
2486 ->get_column( $colinfo->{$rel}{fk_map}{$_} )
2490 keys %{$colinfo->{$rel}{fk_map}}
2491 })->populate( ref $sl->{$rel} eq 'ARRAY' ? $sl->{$rel} : [ $sl->{$rel} ] );
2498 $guard->commit if $guard;
2505 =item Arguments: none
2507 =item Return Value: L<$pager|Data::Page>
2511 Returns a L<Data::Page> object for the current resultset. Only makes
2512 sense for queries with a C<page> attribute.
2514 To get the full count of entries for a paged resultset, call
2515 C<total_entries> on the L<Data::Page> object.
2522 return $self->{pager} if $self->{pager};
2524 my $attrs = $self->{attrs};
2525 if (!defined $attrs->{page}) {
2526 $self->throw_exception("Can't create pager for non-paged rs");
2528 elsif ($attrs->{page} <= 0) {
2529 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2531 $attrs->{rows} ||= 10;
2533 # throw away the paging flags and re-run the count (possibly
2534 # with a subselect) to get the real total count
2535 my $count_attrs = { %$attrs };
2536 delete @{$count_attrs}{qw/rows offset page pager/};
2538 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2540 require DBIx::Class::ResultSet::Pager;
2541 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2542 sub { $total_rs->count }, #lazy-get the total
2544 $self->{attrs}{page},
2552 =item Arguments: $page_number
2554 =item Return Value: L<$resultset|/search>
2558 Returns a resultset for the $page_number page of the resultset on which page
2559 is called, where each page contains a number of rows equal to the 'rows'
2560 attribute set on the resultset (10 by default).
2565 my ($self, $page) = @_;
2566 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2573 =item Arguments: \%col_data
2575 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2579 Creates a new result object in the resultset's result class and returns
2580 it. The row is not inserted into the database at this point, call
2581 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2582 will tell you whether the result object has been inserted or not.
2584 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2589 my ($self, $values) = @_;
2591 $self->throw_exception( "new_result takes only one argument - a hashref of values" )
2594 $self->throw_exception( "Result object instantiation requires a hashref as argument" )
2595 unless (ref $values eq 'HASH');
2597 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2599 my $new = $self->result_class->new({
2601 ( @$cols_from_relations
2602 ? (-cols_from_relations => $cols_from_relations)
2605 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2609 reftype($new) eq 'HASH'
2615 carp_unique (sprintf (
2616 "%s->new returned a blessed empty hashref - a strong indicator something is wrong with its inheritance chain",
2617 $self->result_class,
2624 # _merge_with_rscond
2626 # Takes a simple hash of K/V data and returns its copy merged with the
2627 # condition already present on the resultset. Additionally returns an
2628 # arrayref of value/condition names, which were inferred from related
2629 # objects (this is needed for in-memory related objects)
2630 sub _merge_with_rscond {
2631 my ($self, $data) = @_;
2633 my ($implied_data, @cols_from_relations);
2635 my $alias = $self->{attrs}{alias};
2637 if (! defined $self->{cond}) {
2638 # just massage $data below
2640 elsif ($self->{cond} eq UNRESOLVABLE_CONDITION) {
2641 $implied_data = $self->{attrs}{related_objects}; # nothing might have been inserted yet
2642 @cols_from_relations = keys %{ $implied_data || {} };
2645 my $eqs = $self->result_source->schema->storage->_extract_fixed_condition_columns($self->{cond}, 'consider_nulls');
2646 $implied_data = { map {
2647 ( ($eqs->{$_}||'') eq UNRESOLVABLE_CONDITION ) ? () : ( $_ => $eqs->{$_} )
2653 { %{ $self->_remove_alias($_, $alias) } }
2654 # precedence must be given to passed values over values inherited from
2655 # the cond, so the order here is important.
2656 ( $implied_data||(), $data)
2658 \@cols_from_relations
2662 # _has_resolved_attr
2664 # determines if the resultset defines at least one
2665 # of the attributes supplied
2667 # used to determine if a subquery is necessary
2669 # supports some virtual attributes:
2671 # This will scan for any joins being present on the resultset.
2672 # It is not a mere key-search but a deep inspection of {from}
2675 sub _has_resolved_attr {
2676 my ($self, @attr_names) = @_;
2678 my $attrs = $self->_resolved_attrs;
2682 for my $n (@attr_names) {
2683 if (grep { $n eq $_ } (qw/-join/) ) {
2684 $extra_checks{$n}++;
2688 my $attr = $attrs->{$n};
2690 next if not defined $attr;
2692 if (ref $attr eq 'HASH') {
2693 return 1 if keys %$attr;
2695 elsif (ref $attr eq 'ARRAY') {
2703 # a resolved join is expressed as a multi-level from
2705 $extra_checks{-join}
2707 ref $attrs->{from} eq 'ARRAY'
2709 @{$attrs->{from}} > 1
2717 # Remove the specified alias from the specified query hash. A copy is made so
2718 # the original query is not modified.
2721 my ($self, $query, $alias) = @_;
2723 my %orig = %{ $query || {} };
2726 foreach my $key (keys %orig) {
2728 $unaliased{$key} = $orig{$key};
2731 $unaliased{$1} = $orig{$key}
2732 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2742 =item Arguments: none
2744 =item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
2748 Returns the SQL query and bind vars associated with the invocant.
2750 This is generally used as the RHS for a subquery.
2757 my $attrs = { %{ $self->_resolved_attrs } };
2759 my $aq = $self->result_source->storage->_select_args_to_query (
2760 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
2770 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2772 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2776 my $artist = $schema->resultset('Artist')->find_or_new(
2777 { artist => 'fred' }, { key => 'artists' });
2779 $cd->cd_to_producer->find_or_new({ producer => $producer },
2780 { key => 'primary' });
2782 Find an existing record from this resultset using L</find>. if none exists,
2783 instantiate a new result object and return it. The object will not be saved
2784 into your storage until you call L<DBIx::Class::Row/insert> on it.
2786 You most likely want this method when looking for existing rows using a unique
2787 constraint that is not the primary key, or looking for related rows.
2789 If you want objects to be saved immediately, use L</find_or_create> instead.
2791 B<Note>: Make sure to read the documentation of L</find> and understand the
2792 significance of the C<key> attribute, as its lack may skew your search, and
2793 subsequently result in spurious new objects.
2795 B<Note>: Take care when using C<find_or_new> with a table having
2796 columns with default values that you intend to be automatically
2797 supplied by the database (e.g. an auto_increment primary key column).
2798 In normal usage, the value of such columns should NOT be included at
2799 all in the call to C<find_or_new>, even when set to C<undef>.
2805 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2806 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2807 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2810 return $self->new_result($hash);
2817 =item Arguments: \%col_data
2819 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2823 Attempt to create a single new row or a row with multiple related rows
2824 in the table represented by the resultset (and related tables). This
2825 will not check for duplicate rows before inserting, use
2826 L</find_or_create> to do that.
2828 To create one row for this resultset, pass a hashref of key/value
2829 pairs representing the columns of the table and the values you wish to
2830 store. If the appropriate relationships are set up, foreign key fields
2831 can also be passed an object representing the foreign row, and the
2832 value will be set to its primary key.
2834 To create related objects, pass a hashref of related-object column values
2835 B<keyed on the relationship name>. If the relationship is of type C<multi>
2836 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2837 The process will correctly identify columns holding foreign keys, and will
2838 transparently populate them from the keys of the corresponding relation.
2839 This can be applied recursively, and will work correctly for a structure
2840 with an arbitrary depth and width, as long as the relationships actually
2841 exists and the correct column data has been supplied.
2843 Instead of hashrefs of plain related data (key/value pairs), you may
2844 also pass new or inserted objects. New objects (not inserted yet, see
2845 L</new_result>), will be inserted into their appropriate tables.
2847 Effectively a shortcut for C<< ->new_result(\%col_data)->insert >>.
2849 Example of creating a new row.
2851 $person_rs->create({
2852 name=>"Some Person",
2853 email=>"somebody@someplace.com"
2856 Example of creating a new row and also creating rows in a related C<has_many>
2857 or C<has_one> resultset. Note Arrayref.
2860 { artistid => 4, name => 'Manufactured Crap', cds => [
2861 { title => 'My First CD', year => 2006 },
2862 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2867 Example of creating a new row and also creating a row in a related
2868 C<belongs_to> resultset. Note Hashref.
2871 title=>"Music for Silly Walks",
2874 name=>"Silly Musician",
2882 When subclassing ResultSet never attempt to override this method. Since
2883 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2884 lot of the internals simply never call it, so your override will be
2885 bypassed more often than not. Override either L<DBIx::Class::Row/new>
2886 or L<DBIx::Class::Row/insert> depending on how early in the
2887 L</create> process you need to intervene. See also warning pertaining to
2895 #my ($self, $col_data) = @_;
2896 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
2897 return shift->new_result(shift)->insert;
2900 =head2 find_or_create
2904 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2906 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2910 $cd->cd_to_producer->find_or_create({ producer => $producer },
2911 { key => 'primary' });
2913 Tries to find a record based on its primary key or unique constraints; if none
2914 is found, creates one and returns that instead.
2916 my $cd = $schema->resultset('CD')->find_or_create({
2918 artist => 'Massive Attack',
2919 title => 'Mezzanine',
2923 Also takes an optional C<key> attribute, to search by a specific key or unique
2924 constraint. For example:
2926 my $cd = $schema->resultset('CD')->find_or_create(
2928 artist => 'Massive Attack',
2929 title => 'Mezzanine',
2931 { key => 'cd_artist_title' }
2934 B<Note>: Make sure to read the documentation of L</find> and understand the
2935 significance of the C<key> attribute, as its lack may skew your search, and
2936 subsequently result in spurious row creation.
2938 B<Note>: Because find_or_create() reads from the database and then
2939 possibly inserts based on the result, this method is subject to a race
2940 condition. Another process could create a record in the table after
2941 the find has completed and before the create has started. To avoid
2942 this problem, use find_or_create() inside a transaction.
2944 B<Note>: Take care when using C<find_or_create> with a table having
2945 columns with default values that you intend to be automatically
2946 supplied by the database (e.g. an auto_increment primary key column).
2947 In normal usage, the value of such columns should NOT be included at
2948 all in the call to C<find_or_create>, even when set to C<undef>.
2950 See also L</find> and L</update_or_create>. For information on how to declare
2951 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2953 If you need to know if an existing row was found or a new one created use
2954 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2955 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2958 my $cd = $schema->resultset('CD')->find_or_new({
2960 artist => 'Massive Attack',
2961 title => 'Mezzanine',
2965 if( !$cd->in_storage ) {
2972 sub find_or_create {
2974 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2975 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2976 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2979 return $self->new_result($hash)->insert;
2982 =head2 update_or_create
2986 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2988 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2992 $resultset->update_or_create({ col => $val, ... });
2994 Like L</find_or_create>, but if a row is found it is immediately updated via
2995 C<< $found_row->update (\%col_data) >>.
2998 Takes an optional C<key> attribute to search on a specific unique constraint.
3001 # In your application
3002 my $cd = $schema->resultset('CD')->update_or_create(
3004 artist => 'Massive Attack',
3005 title => 'Mezzanine',
3008 { key => 'cd_artist_title' }
3011 $cd->cd_to_producer->update_or_create({
3012 producer => $producer,
3018 B<Note>: Make sure to read the documentation of L</find> and understand the
3019 significance of the C<key> attribute, as its lack may skew your search, and
3020 subsequently result in spurious row creation.
3022 B<Note>: Take care when using C<update_or_create> with a table having
3023 columns with default values that you intend to be automatically
3024 supplied by the database (e.g. an auto_increment primary key column).
3025 In normal usage, the value of such columns should NOT be included at
3026 all in the call to C<update_or_create>, even when set to C<undef>.
3028 See also L</find> and L</find_or_create>. For information on how to declare
3029 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
3031 If you need to know if an existing row was updated or a new one created use
3032 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
3033 to call L<DBIx::Class::Row/insert> to save the newly created row to the
3038 sub update_or_create {
3040 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
3041 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3043 my $row = $self->find($cond, $attrs);
3045 $row->update($cond);
3049 return $self->new_result($cond)->insert;
3052 =head2 update_or_new
3056 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
3058 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
3062 $resultset->update_or_new({ col => $val, ... });
3064 Like L</find_or_new> but if a row is found it is immediately updated via
3065 C<< $found_row->update (\%col_data) >>.
3069 # In your application
3070 my $cd = $schema->resultset('CD')->update_or_new(
3072 artist => 'Massive Attack',
3073 title => 'Mezzanine',
3076 { key => 'cd_artist_title' }
3079 if ($cd->in_storage) {
3080 # the cd was updated
3083 # the cd is not yet in the database, let's insert it
3087 B<Note>: Make sure to read the documentation of L</find> and understand the
3088 significance of the C<key> attribute, as its lack may skew your search, and
3089 subsequently result in spurious new objects.
3091 B<Note>: Take care when using C<update_or_new> with a table having
3092 columns with default values that you intend to be automatically
3093 supplied by the database (e.g. an auto_increment primary key column).
3094 In normal usage, the value of such columns should NOT be included at
3095 all in the call to C<update_or_new>, even when set to C<undef>.
3097 See also L</find>, L</find_or_create> and L</find_or_new>.
3103 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
3104 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3106 my $row = $self->find( $cond, $attrs );
3107 if ( defined $row ) {
3108 $row->update($cond);
3112 return $self->new_result($cond);
3119 =item Arguments: none
3121 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass> | undef
3125 Gets the contents of the cache for the resultset, if the cache is set.
3127 The cache is populated either by using the L</prefetch> attribute to
3128 L</search> or by calling L</set_cache>.
3140 =item Arguments: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3142 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3146 Sets the contents of the cache for the resultset. Expects an arrayref
3147 of objects of the same class as those produced by the resultset. Note that
3148 if the cache is set, the resultset will return the cached objects rather
3149 than re-querying the database even if the cache attr is not set.
3151 The contents of the cache can also be populated by using the
3152 L</prefetch> attribute to L</search>.
3157 my ( $self, $data ) = @_;
3158 $self->throw_exception("set_cache requires an arrayref")
3159 if defined($data) && (ref $data ne 'ARRAY');
3160 $self->{all_cache} = $data;
3167 =item Arguments: none
3169 =item Return Value: undef
3173 Clears the cache for the resultset.
3178 shift->set_cache(undef);
3185 =item Arguments: none
3187 =item Return Value: true, if the resultset has been paginated
3195 return !!$self->{attrs}{page};
3202 =item Arguments: none
3204 =item Return Value: true, if the resultset has been ordered with C<order_by>.
3212 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
3215 =head2 related_resultset
3219 =item Arguments: $rel_name
3221 =item Return Value: L<$resultset|/search>
3225 Returns a related resultset for the supplied relationship name.
3227 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
3231 sub related_resultset {
3232 my ($self, $rel) = @_;
3234 return $self->{related_resultsets}{$rel}
3235 if defined $self->{related_resultsets}{$rel};
3237 return $self->{related_resultsets}{$rel} = do {
3238 my $rsrc = $self->result_source;
3239 my $rel_info = $rsrc->relationship_info($rel);
3241 $self->throw_exception(
3242 "search_related: result source '" . $rsrc->source_name .
3243 "' has no such relationship $rel")
3246 my $attrs = $self->_chain_relationship($rel);
3248 my $join_count = $attrs->{seen_join}{$rel};
3250 my $alias = $self->result_source->storage
3251 ->relname_to_table_alias($rel, $join_count);
3253 # since this is search_related, and we already slid the select window inwards
3254 # (the select/as attrs were deleted in the beginning), we need to flip all
3255 # left joins to inner, so we get the expected results
3256 # read the comment on top of the actual function to see what this does
3257 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
3260 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3261 delete @{$attrs}{qw(result_class alias)};
3263 my $rel_source = $rsrc->related_source($rel);
3267 # The reason we do this now instead of passing the alias to the
3268 # search_rs below is that if you wrap/overload resultset on the
3269 # source you need to know what alias it's -going- to have for things
3270 # to work sanely (e.g. RestrictWithObject wants to be able to add
3271 # extra query restrictions, and these may need to be $alias.)
3273 my $rel_attrs = $rel_source->resultset_attributes;
3274 local $rel_attrs->{alias} = $alias;
3276 $rel_source->resultset
3280 where => $attrs->{where},
3284 if (my $cache = $self->get_cache) {
3285 my @related_cache = map
3286 { $_->related_resultset($rel)->get_cache || () }
3290 $new->set_cache([ map @$_, @related_cache ]) if @related_cache == @$cache;
3297 =head2 current_source_alias
3301 =item Arguments: none
3303 =item Return Value: $source_alias
3307 Returns the current table alias for the result source this resultset is built
3308 on, that will be used in the SQL query. Usually it is C<me>.
3310 Currently the source alias that refers to the result set returned by a
3311 L</search>/L</find> family method depends on how you got to the resultset: it's
3312 C<me> by default, but eg. L</search_related> aliases it to the related result
3313 source name (and keeps C<me> referring to the original result set). The long
3314 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3315 (and make this method unnecessary).
3317 Thus it's currently necessary to use this method in predefined queries (see
3318 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3319 source alias of the current result set:
3321 # in a result set class
3323 my ($self, $user) = @_;
3325 my $me = $self->current_source_alias;
3327 return $self->search({
3328 "$me.modified" => $user->id,
3334 sub current_source_alias {
3335 return (shift->{attrs} || {})->{alias} || 'me';
3338 =head2 as_subselect_rs
3342 =item Arguments: none
3344 =item Return Value: L<$resultset|/search>
3348 Act as a barrier to SQL symbols. The resultset provided will be made into a
3349 "virtual view" by including it as a subquery within the from clause. From this
3350 point on, any joined tables are inaccessible to ->search on the resultset (as if
3351 it were simply where-filtered without joins). For example:
3353 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3355 # 'x' now pollutes the query namespace
3357 # So the following works as expected
3358 my $ok_rs = $rs->search({'x.other' => 1});
3360 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3361 # def) we look for one row with contradictory terms and join in another table
3362 # (aliased 'x_2') which we never use
3363 my $broken_rs = $rs->search({'x.name' => 'def'});
3365 my $rs2 = $rs->as_subselect_rs;
3367 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3368 my $not_joined_rs = $rs2->search({'x.other' => 1});
3370 # works as expected: finds a 'table' row related to two x rows (abc and def)
3371 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3373 Another example of when one might use this would be to select a subset of
3374 columns in a group by clause:
3376 my $rs = $schema->resultset('Bar')->search(undef, {
3377 group_by => [qw{ id foo_id baz_id }],
3378 })->as_subselect_rs->search(undef, {
3379 columns => [qw{ id foo_id }]
3382 In the above example normally columns would have to be equal to the group by,
3383 but because we isolated the group by into a subselect the above works.
3387 sub as_subselect_rs {
3390 my $attrs = $self->_resolved_attrs;
3392 my $fresh_rs = (ref $self)->new (
3393 $self->result_source
3396 # these pieces will be locked in the subquery
3397 delete $fresh_rs->{cond};
3398 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3400 return $fresh_rs->search( {}, {
3402 $attrs->{alias} => $self->as_query,
3403 -alias => $attrs->{alias},
3404 -rsrc => $self->result_source,
3406 alias => $attrs->{alias},
3410 # This code is called by search_related, and makes sure there
3411 # is clear separation between the joins before, during, and
3412 # after the relationship. This information is needed later
3413 # in order to properly resolve prefetch aliases (any alias
3414 # with a relation_chain_depth less than the depth of the
3415 # current prefetch is not considered)
3417 # The increments happen twice per join. An even number means a
3418 # relationship specified via a search_related, whereas an odd
3419 # number indicates a join/prefetch added via attributes
3421 # Also this code will wrap the current resultset (the one we
3422 # chain to) in a subselect IFF it contains limiting attributes
3423 sub _chain_relationship {
3424 my ($self, $rel) = @_;
3425 my $source = $self->result_source;
3426 my $attrs = { %{$self->{attrs}||{}} };
3428 # we need to take the prefetch the attrs into account before we
3429 # ->_resolve_join as otherwise they get lost - captainL
3430 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3432 delete @{$attrs}{qw/join prefetch collapse group_by distinct _grouped_by_distinct select as columns +select +as +columns/};
3434 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3437 my @force_subq_attrs = qw/offset rows group_by having/;
3440 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3442 $self->_has_resolved_attr (@force_subq_attrs)
3444 # Nuke the prefetch (if any) before the new $rs attrs
3445 # are resolved (prefetch is useless - we are wrapping
3446 # a subquery anyway).
3447 my $rs_copy = $self->search;
3448 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3449 $rs_copy->{attrs}{join},
3450 delete $rs_copy->{attrs}{prefetch},
3455 -alias => $attrs->{alias},
3456 $attrs->{alias} => $rs_copy->as_query,
3458 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3459 $seen->{-relation_chain_depth} = 0;
3461 elsif ($attrs->{from}) { #shallow copy suffices
3462 $from = [ @{$attrs->{from}} ];
3467 -alias => $attrs->{alias},
3468 $attrs->{alias} => $source->from,
3472 my $jpath = ($seen->{-relation_chain_depth})
3473 ? $from->[-1][0]{-join_path}
3476 my @requested_joins = $source->_resolve_join(
3483 push @$from, @requested_joins;
3485 $seen->{-relation_chain_depth}++;
3487 # if $self already had a join/prefetch specified on it, the requested
3488 # $rel might very well be already included. What we do in this case
3489 # is effectively a no-op (except that we bump up the chain_depth on
3490 # the join in question so we could tell it *is* the search_related)
3493 # we consider the last one thus reverse
3494 for my $j (reverse @requested_joins) {
3495 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3496 if ($rel eq $last_j) {
3497 $j->[0]{-relation_chain_depth}++;
3503 unless ($already_joined) {
3504 push @$from, $source->_resolve_join(
3512 $seen->{-relation_chain_depth}++;
3514 return {%$attrs, from => $from, seen_join => $seen};
3517 sub _resolved_attrs {
3519 return $self->{_attrs} if $self->{_attrs};
3521 my $attrs = { %{ $self->{attrs} || {} } };
3522 my $source = $attrs->{result_source} = $self->result_source;
3523 my $alias = $attrs->{alias};
3525 $self->throw_exception("Specifying distinct => 1 in conjunction with collapse => 1 is unsupported")
3526 if $attrs->{collapse} and $attrs->{distinct};
3528 # default selection list
3529 $attrs->{columns} = [ $source->columns ]
3530 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3532 # merge selectors together
3533 for (qw/columns select as/) {
3534 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3535 if $attrs->{$_} or $attrs->{"+$_"};
3538 # disassemble columns
3540 if (my $cols = delete $attrs->{columns}) {
3541 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3542 if (ref $c eq 'HASH') {
3543 for my $as (sort keys %$c) {
3544 push @sel, $c->{$as};
3555 # when trying to weed off duplicates later do not go past this point -
3556 # everything added from here on is unbalanced "anyone's guess" stuff
3557 my $dedup_stop_idx = $#as;
3559 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3561 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3562 if $attrs->{select};
3564 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3565 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3567 # disqualify all $alias.col as-bits (inflate-map mandated)
3568 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3570 # de-duplicate the result (remove *identical* select/as pairs)
3571 # and also die on duplicate {as} pointing to different {select}s
3572 # not using a c-style for as the condition is prone to shrinkage
3575 while ($i <= $dedup_stop_idx) {
3576 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3581 elsif ($seen->{$as[$i]}++) {
3582 $self->throw_exception(
3583 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3591 $attrs->{select} = \@sel;
3592 $attrs->{as} = \@as;
3594 $attrs->{from} ||= [{
3596 -alias => $self->{attrs}{alias},
3597 $self->{attrs}{alias} => $source->from,
3600 if ( $attrs->{join} || $attrs->{prefetch} ) {
3602 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3603 if ref $attrs->{from} ne 'ARRAY';
3605 my $join = (delete $attrs->{join}) || {};
3607 if ( defined $attrs->{prefetch} ) {
3608 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3611 $attrs->{from} = # have to copy here to avoid corrupting the original
3613 @{ $attrs->{from} },
3614 $source->_resolve_join(
3617 { %{ $attrs->{seen_join} || {} } },
3618 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3619 ? $attrs->{from}[-1][0]{-join_path}
3626 if ( defined $attrs->{order_by} ) {
3627 $attrs->{order_by} = (
3628 ref( $attrs->{order_by} ) eq 'ARRAY'
3629 ? [ @{ $attrs->{order_by} } ]
3630 : [ $attrs->{order_by} || () ]
3634 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3635 $attrs->{group_by} = [ $attrs->{group_by} ];
3639 # generate selections based on the prefetch helper
3640 my ($prefetch, @prefetch_select, @prefetch_as);
3641 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3642 if defined $attrs->{prefetch};
3646 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3647 if $attrs->{_dark_selector};
3649 $self->throw_exception("Specifying prefetch in conjunction with an explicit collapse => 0 is unsupported")
3650 if defined $attrs->{collapse} and ! $attrs->{collapse};
3652 $attrs->{collapse} = 1;
3654 # this is a separate structure (we don't look in {from} directly)
3655 # as the resolver needs to shift things off the lists to work
3656 # properly (identical-prefetches on different branches)
3658 if (ref $attrs->{from} eq 'ARRAY') {
3660 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3662 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3663 next unless $j->[0]{-alias};
3664 next unless $j->[0]{-join_path};
3665 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3667 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3670 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3671 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3675 my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map );
3677 # save these for after distinct resolution
3678 @prefetch_select = map { $_->[0] } @prefetch;
3679 @prefetch_as = map { $_->[1] } @prefetch;
3682 # run through the resulting joinstructure (starting from our current slot)
3683 # and unset collapse if proven unnecessary
3685 # also while we are at it find out if the current root source has
3686 # been premultiplied by previous related_source chaining
3688 # this allows to predict whether a root object with all other relation
3689 # data set to NULL is in fact unique
3690 if ($attrs->{collapse}) {
3692 if (ref $attrs->{from} eq 'ARRAY') {
3694 if (@{$attrs->{from}} == 1) {
3695 # no joins - no collapse
3696 $attrs->{collapse} = 0;
3699 # find where our table-spec starts
3700 my @fromlist = @{$attrs->{from}};
3702 my $t = shift @fromlist;
3705 # me vs join from-spec distinction - a ref means non-root
3706 if (ref $t eq 'ARRAY') {
3708 $is_multi ||= ! $t->{-is_single};
3710 last if ($t->{-alias} && $t->{-alias} eq $alias);
3711 $attrs->{_main_source_premultiplied} ||= $is_multi;
3714 # no non-singles remaining, nor any premultiplication - nothing to collapse
3716 ! $attrs->{_main_source_premultiplied}
3718 ! List::Util::first { ! $_->[0]{-is_single} } @fromlist
3720 $attrs->{collapse} = 0;
3726 # if we can not analyze the from - err on the side of safety
3727 $attrs->{_main_source_premultiplied} = 1;
3731 # generate the distinct induced group_by before injecting the prefetched select/as parts
3732 if (delete $attrs->{distinct}) {
3733 if ($attrs->{group_by}) {
3734 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3737 $attrs->{_grouped_by_distinct} = 1;
3738 # distinct affects only the main selection part, not what prefetch may add below
3739 ($attrs->{group_by}, my $new_order) = $source->storage->_group_over_selection($attrs);
3741 # FIXME possibly ignore a rewritten order_by (may turn out to be an issue)
3742 # The thinking is: if we are collapsing the subquerying prefetch engine will
3743 # rip stuff apart for us anyway, and we do not want to have a potentially
3744 # function-converted external order_by
3745 # ( there is an explicit if ( collapse && _grouped_by_distinct ) check in DBIHacks )
3746 $attrs->{order_by} = $new_order unless $attrs->{collapse};
3750 # inject prefetch-bound selection (if any)
3751 push @{$attrs->{select}}, @prefetch_select;
3752 push @{$attrs->{as}}, @prefetch_as;
3754 $attrs->{_simple_passthrough_construction} = !(
3757 grep { $_ =~ /\./ } @{$attrs->{as}}
3760 # if both page and offset are specified, produce a combined offset
3761 # even though it doesn't make much sense, this is what pre 081xx has
3763 if (my $page = delete $attrs->{page}) {
3765 ($attrs->{rows} * ($page - 1))
3767 ($attrs->{offset} || 0)
3771 return $self->{_attrs} = $attrs;
3775 my ($self, $attr) = @_;
3777 if (ref $attr eq 'HASH') {
3778 return $self->_rollout_hash($attr);
3779 } elsif (ref $attr eq 'ARRAY') {
3780 return $self->_rollout_array($attr);
3786 sub _rollout_array {
3787 my ($self, $attr) = @_;
3790 foreach my $element (@{$attr}) {
3791 if (ref $element eq 'HASH') {
3792 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3793 } elsif (ref $element eq 'ARRAY') {
3794 # XXX - should probably recurse here
3795 push( @rolled_array, @{$self->_rollout_array($element)} );
3797 push( @rolled_array, $element );
3800 return \@rolled_array;
3804 my ($self, $attr) = @_;
3807 foreach my $key (keys %{$attr}) {
3808 push( @rolled_array, { $key => $attr->{$key} } );
3810 return \@rolled_array;
3813 sub _calculate_score {
3814 my ($self, $a, $b) = @_;
3816 if (defined $a xor defined $b) {
3819 elsif (not defined $a) {
3823 if (ref $b eq 'HASH') {
3824 my ($b_key) = keys %{$b};
3825 if (ref $a eq 'HASH') {
3826 my ($a_key) = keys %{$a};
3827 if ($a_key eq $b_key) {
3828 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3833 return ($a eq $b_key) ? 1 : 0;
3836 if (ref $a eq 'HASH') {
3837 my ($a_key) = keys %{$a};
3838 return ($b eq $a_key) ? 1 : 0;
3840 return ($b eq $a) ? 1 : 0;
3845 sub _merge_joinpref_attr {
3846 my ($self, $orig, $import) = @_;
3848 return $import unless defined($orig);
3849 return $orig unless defined($import);
3851 $orig = $self->_rollout_attr($orig);
3852 $import = $self->_rollout_attr($import);
3855 foreach my $import_element ( @{$import} ) {
3856 # find best candidate from $orig to merge $b_element into
3857 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3858 foreach my $orig_element ( @{$orig} ) {
3859 my $score = $self->_calculate_score( $orig_element, $import_element );
3860 if ($score > $best_candidate->{score}) {
3861 $best_candidate->{position} = $position;
3862 $best_candidate->{score} = $score;
3866 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3867 $import_key = '' if not defined $import_key;
3869 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3870 push( @{$orig}, $import_element );
3872 my $orig_best = $orig->[$best_candidate->{position}];
3873 # merge orig_best and b_element together and replace original with merged
3874 if (ref $orig_best ne 'HASH') {
3875 $orig->[$best_candidate->{position}] = $import_element;
3876 } elsif (ref $import_element eq 'HASH') {
3877 my ($key) = keys %{$orig_best};
3878 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3881 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3884 return @$orig ? $orig : ();
3892 require Hash::Merge;
3893 my $hm = Hash::Merge->new;
3895 $hm->specify_behavior({
3898 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3900 if ($defl xor $defr) {
3901 return [ $defl ? $_[0] : $_[1] ];
3906 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3910 return [$_[0], $_[1]];
3914 return $_[1] if !defined $_[0];
3915 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3916 return [$_[0], @{$_[1]}]
3919 return [] if !defined $_[0] and !keys %{$_[1]};
3920 return [ $_[1] ] if !defined $_[0];
3921 return [ $_[0] ] if !keys %{$_[1]};
3922 return [$_[0], $_[1]]
3927 return $_[0] if !defined $_[1];
3928 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3929 return [@{$_[0]}, $_[1]]
3932 my @ret = @{$_[0]} or return $_[1];
3933 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3934 my %idx = map { $_ => 1 } @ret;
3935 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3939 return [ $_[1] ] if ! @{$_[0]};
3940 return $_[0] if !keys %{$_[1]};
3941 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3942 return [ @{$_[0]}, $_[1] ];
3947 return [] if !keys %{$_[0]} and !defined $_[1];
3948 return [ $_[0] ] if !defined $_[1];
3949 return [ $_[1] ] if !keys %{$_[0]};
3950 return [$_[0], $_[1]]
3953 return [] if !keys %{$_[0]} and !@{$_[1]};
3954 return [ $_[0] ] if !@{$_[1]};
3955 return $_[1] if !keys %{$_[0]};
3956 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3957 return [ $_[0], @{$_[1]} ];
3960 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3961 return [ $_[0] ] if !keys %{$_[1]};
3962 return [ $_[1] ] if !keys %{$_[0]};
3963 return [ $_[0] ] if $_[0] eq $_[1];
3964 return [ $_[0], $_[1] ];
3967 } => 'DBIC_RS_ATTR_MERGER');
3971 return $hm->merge ($_[1], $_[2]);
3975 sub STORABLE_freeze {
3976 my ($self, $cloning) = @_;
3977 my $to_serialize = { %$self };
3979 # A cursor in progress can't be serialized (and would make little sense anyway)
3980 # the parser can be regenerated (and can't be serialized)
3981 delete @{$to_serialize}{qw/cursor _row_parser _result_inflator/};
3983 # nor is it sensical to store a not-yet-fired-count pager
3984 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3985 delete $to_serialize->{pager};
3988 Storable::nfreeze($to_serialize);
3991 # need this hook for symmetry
3993 my ($self, $cloning, $serialized) = @_;
3995 %$self = %{ Storable::thaw($serialized) };
4001 =head2 throw_exception
4003 See L<DBIx::Class::Schema/throw_exception> for details.
4007 sub throw_exception {
4010 if (ref $self and my $rsrc = $self->result_source) {
4011 $rsrc->throw_exception(@_)
4014 DBIx::Class::Exception->throw(@_);
4022 # XXX: FIXME: Attributes docs need clearing up
4026 Attributes are used to refine a ResultSet in various ways when
4027 searching for data. They can be passed to any method which takes an
4028 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
4031 Default attributes can be set on the result class using
4032 L<DBIx::Class::ResultSource/resultset_attributes>. (Please read
4033 the CAVEATS on that feature before using it!)
4035 These are in no particular order:
4041 =item Value: ( $order_by | \@order_by | \%order_by )
4045 Which column(s) to order the results by.
4047 [The full list of suitable values is documented in
4048 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
4051 If a single column name, or an arrayref of names is supplied, the
4052 argument is passed through directly to SQL. The hashref syntax allows
4053 for connection-agnostic specification of ordering direction:
4055 For descending order:
4057 order_by => { -desc => [qw/col1 col2 col3/] }
4059 For explicit ascending order:
4061 order_by => { -asc => 'col' }
4063 The old scalarref syntax (i.e. order_by => \'year DESC') is still
4064 supported, although you are strongly encouraged to use the hashref
4065 syntax as outlined above.
4071 =item Value: \@columns | \%columns | $column
4075 Shortcut to request a particular set of columns to be retrieved. Each
4076 column spec may be a string (a table column name), or a hash (in which
4077 case the key is the C<as> value, and the value is used as the C<select>
4078 expression). Adds the L</current_source_alias> onto the start of any column without a C<.> in
4079 it and sets C<select> from that, then auto-populates C<as> from
4080 C<select> as normal. (You may also use the C<cols> attribute, as in
4081 earlier versions of DBIC, but this is deprecated)
4083 Essentially C<columns> does the same as L</select> and L</as>.
4085 columns => [ 'some_column', { dbic_slot => 'another_column' } ]
4089 select => [qw(some_column another_column)],
4090 as => [qw(some_column dbic_slot)]
4092 If you want to individually retrieve related columns (in essence perform
4093 manual prefetch) you have to make sure to specify the correct inflation slot
4094 chain such that it matches existing relationships:
4096 my $rs = $schema->resultset('Artist')->search({}, {
4097 # required to tell DBIC to collapse has_many relationships
4099 join => { cds => 'tracks'},
4101 'cds.cdid' => 'cds.cdid',
4102 'cds.tracks.title' => 'tracks.title',
4108 B<NOTE:> You B<MUST> explicitly quote C<'+columns'> when using this attribute.
4109 Not doing so causes Perl to incorrectly interpret C<+columns> as a bareword
4110 with a unary plus operator before it, which is the same as simply C<columns>.
4114 =item Value: \@extra_columns
4118 Indicates additional columns to be selected from storage. Works the same as
4119 L</columns> but adds columns to the current selection. (You may also use the
4120 C<include_columns> attribute, as in earlier versions of DBIC, but this is
4123 $schema->resultset('CD')->search(undef, {
4124 '+columns' => ['artist.name'],
4128 would return all CDs and include a 'name' column to the information
4129 passed to object inflation. Note that the 'artist' is the name of the
4130 column (or relationship) accessor, and 'name' is the name of the column
4131 accessor in the related table.
4137 =item Value: \@select_columns
4141 Indicates which columns should be selected from the storage. You can use
4142 column names, or in the case of RDBMS back ends, function or stored procedure
4145 $rs = $schema->resultset('Employee')->search(undef, {
4148 { count => 'employeeid' },
4149 { max => { length => 'name' }, -as => 'longest_name' }
4154 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
4156 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
4157 use L</select>, to instruct DBIx::Class how to store the result of the column.
4158 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
4159 identifier aliasing. You can however alias a function, so you can use it in
4160 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
4161 attribute> supplied as shown in the example above.
4165 B<NOTE:> You B<MUST> explicitly quote C<'+select'> when using this attribute.
4166 Not doing so causes Perl to incorrectly interpret C<+select> as a bareword
4167 with a unary plus operator before it, which is the same as simply C<select>.
4171 =item Value: \@extra_select_columns
4175 Indicates additional columns to be selected from storage. Works the same as
4176 L</select> but adds columns to the current selection, instead of specifying
4177 a new explicit list.
4183 =item Value: \@inflation_names
4187 Indicates DBIC-side names for object inflation. That is L</as> indicates the
4188 slot name in which the column value will be stored within the
4189 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
4190 identifier by the C<get_column> method (or via the object accessor B<if one
4191 with the same name already exists>) as shown below. The L</as> attribute has
4192 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
4194 $rs = $schema->resultset('Employee')->search(undef, {
4197 { count => 'employeeid' },
4198 { max => { length => 'name' }, -as => 'longest_name' }
4207 If the object against which the search is performed already has an accessor
4208 matching a column name specified in C<as>, the value can be retrieved using
4209 the accessor as normal:
4211 my $name = $employee->name();
4213 If on the other hand an accessor does not exist in the object, you need to
4214 use C<get_column> instead:
4216 my $employee_count = $employee->get_column('employee_count');
4218 You can create your own accessors if required - see
4219 L<DBIx::Class::Manual::Cookbook> for details.
4223 B<NOTE:> You B<MUST> explicitly quote C<'+as'> when using this attribute.
4224 Not doing so causes Perl to incorrectly interpret C<+as> as a bareword
4225 with a unary plus operator before it, which is the same as simply C<as>.
4229 =item Value: \@extra_inflation_names
4233 Indicates additional inflation names for selectors added via L</+select>. See L</as>.
4239 =item Value: ($rel_name | \@rel_names | \%rel_names)
4243 Contains a list of relationships that should be joined for this query. For
4246 # Get CDs by Nine Inch Nails
4247 my $rs = $schema->resultset('CD')->search(
4248 { 'artist.name' => 'Nine Inch Nails' },
4249 { join => 'artist' }
4252 Can also contain a hash reference to refer to the other relation's relations.
4255 package MyApp::Schema::Track;
4256 use base qw/DBIx::Class/;
4257 __PACKAGE__->table('track');
4258 __PACKAGE__->add_columns(qw/trackid cd position title/);
4259 __PACKAGE__->set_primary_key('trackid');
4260 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
4263 # In your application
4264 my $rs = $schema->resultset('Artist')->search(
4265 { 'track.title' => 'Teardrop' },
4267 join => { cd => 'track' },
4268 order_by => 'artist.name',
4272 You need to use the relationship (not the table) name in conditions,
4273 because they are aliased as such. The current table is aliased as "me", so
4274 you need to use me.column_name in order to avoid ambiguity. For example:
4276 # Get CDs from 1984 with a 'Foo' track
4277 my $rs = $schema->resultset('CD')->search(
4280 'tracks.name' => 'Foo'
4282 { join => 'tracks' }
4285 If the same join is supplied twice, it will be aliased to <rel>_2 (and
4286 similarly for a third time). For e.g.
4288 my $rs = $schema->resultset('Artist')->search({
4289 'cds.title' => 'Down to Earth',
4290 'cds_2.title' => 'Popular',
4292 join => [ qw/cds cds/ ],
4295 will return a set of all artists that have both a cd with title 'Down
4296 to Earth' and a cd with title 'Popular'.
4298 If you want to fetch related objects from other tables as well, see L</prefetch>
4301 NOTE: An internal join-chain pruner will discard certain joins while
4302 constructing the actual SQL query, as long as the joins in question do not
4303 affect the retrieved result. This for example includes 1:1 left joins
4304 that are not part of the restriction specification (WHERE/HAVING) nor are
4305 a part of the query selection.
4307 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4313 =item Value: (0 | 1)
4317 When set to a true value, indicates that any rows fetched from joined has_many
4318 relationships are to be aggregated into the corresponding "parent" object. For
4319 example, the resultset:
4321 my $rs = $schema->resultset('CD')->search({}, {
4322 '+columns' => [ qw/ tracks.title tracks.position / ],
4327 While executing the following query:
4329 SELECT me.*, tracks.title, tracks.position
4331 LEFT JOIN track tracks
4332 ON tracks.cdid = me.cdid
4334 Will return only as many objects as there are rows in the CD source, even
4335 though the result of the query may span many rows. Each of these CD objects
4336 will in turn have multiple "Track" objects hidden behind the has_many
4337 generated accessor C<tracks>. Without C<< collapse => 1 >>, the return values
4338 of this resultset would be as many CD objects as there are tracks (a "Cartesian
4339 product"), with each CD object containing exactly one of all fetched Track data.
4341 When a collapse is requested on a non-ordered resultset, an order by some
4342 unique part of the main source (the left-most table) is inserted automatically.
4343 This is done so that the resultset is allowed to be "lazy" - calling
4344 L<< $rs->next|/next >> will fetch only as many rows as it needs to build the next
4345 object with all of its related data.
4347 If an L</order_by> is already declared, and orders the resultset in a way that
4348 makes collapsing as described above impossible (e.g. C<< ORDER BY
4349 has_many_rel.column >> or C<ORDER BY RANDOM()>), DBIC will automatically
4350 switch to "eager" mode and slurp the entire resultset before constructing the
4351 first object returned by L</next>.
4353 Setting this attribute on a resultset that does not join any has_many
4354 relations is a no-op.
4356 For a more in-depth discussion, see L</PREFETCHING>.
4362 =item Value: ($rel_name | \@rel_names | \%rel_names)
4366 This attribute is a shorthand for specifying a L</join> spec, adding all
4367 columns from the joined related sources as L</+columns> and setting
4368 L</collapse> to a true value. For example, the following two queries are
4371 my $rs = $schema->resultset('Artist')->search({}, {
4372 prefetch => { cds => ['genre', 'tracks' ] },
4377 my $rs = $schema->resultset('Artist')->search({}, {
4378 join => { cds => ['genre', 'tracks' ] },
4382 { +{ "cds.$_" => "cds.$_" } }
4383 $schema->source('Artist')->related_source('cds')->columns
4386 { +{ "cds.genre.$_" => "genre.$_" } }
4387 $schema->source('Artist')->related_source('cds')->related_source('genre')->columns
4390 { +{ "cds.tracks.$_" => "tracks.$_" } }
4391 $schema->source('Artist')->related_source('cds')->related_source('tracks')->columns
4396 Both producing the following SQL:
4398 SELECT me.artistid, me.name, me.rank, me.charfield,
4399 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track,
4400 genre.genreid, genre.name,
4401 tracks.trackid, tracks.cd, tracks.position, tracks.title, tracks.last_updated_on, tracks.last_updated_at
4404 ON cds.artist = me.artistid
4405 LEFT JOIN genre genre
4406 ON genre.genreid = cds.genreid
4407 LEFT JOIN track tracks
4408 ON tracks.cd = cds.cdid
4409 ORDER BY me.artistid
4411 While L</prefetch> implies a L</join>, it is ok to mix the two together, as
4412 the arguments are properly merged and generally do the right thing. For
4413 example, you may want to do the following:
4415 my $artists_and_cds_without_genre = $schema->resultset('Artist')->search(
4416 { 'genre.genreid' => undef },
4418 join => { cds => 'genre' },
4423 Which generates the following SQL:
4425 SELECT me.artistid, me.name, me.rank, me.charfield,
4426 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track
4429 ON cds.artist = me.artistid
4430 LEFT JOIN genre genre
4431 ON genre.genreid = cds.genreid
4432 WHERE genre.genreid IS NULL
4433 ORDER BY me.artistid
4435 For a more in-depth discussion, see L</PREFETCHING>.
4441 =item Value: $source_alias
4445 Sets the source alias for the query. Normally, this defaults to C<me>, but
4446 nested search queries (sub-SELECTs) might need specific aliases set to
4447 reference inner queries. For example:
4450 ->related_resultset('CDs')
4451 ->related_resultset('Tracks')
4453 'track.id' => { -ident => 'none_search.id' },
4457 my $ids = $self->search({
4460 alias => 'none_search',
4461 group_by => 'none_search.id',
4462 })->get_column('id')->as_query;
4464 $self->search({ id => { -in => $ids } })
4466 This attribute is directly tied to L</current_source_alias>.
4476 Makes the resultset paged and specifies the page to retrieve. Effectively
4477 identical to creating a non-pages resultset and then calling ->page($page)
4480 If L</rows> attribute is not specified it defaults to 10 rows per page.
4482 When you have a paged resultset, L</count> will only return the number
4483 of rows in the page. To get the total, use the L</pager> and call
4484 C<total_entries> on it.
4494 Specifies the maximum number of rows for direct retrieval or the number of
4495 rows per page if the page attribute or method is used.
4501 =item Value: $offset
4505 Specifies the (zero-based) row number for the first row to be returned, or the
4506 of the first row of the first page if paging is used.
4508 =head2 software_limit
4512 =item Value: (0 | 1)
4516 When combined with L</rows> and/or L</offset> the generated SQL will not
4517 include any limit dialect stanzas. Instead the entire result will be selected
4518 as if no limits were specified, and DBIC will perform the limit locally, by
4519 artificially advancing and finishing the resulting L</cursor>.
4521 This is the recommended way of performing resultset limiting when no sane RDBMS
4522 implementation is available (e.g.
4523 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4524 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4530 =item Value: \@columns
4534 A arrayref of columns to group by. Can include columns of joined tables.
4536 group_by => [qw/ column1 column2 ... /]
4542 =item Value: $condition
4546 HAVING is a select statement attribute that is applied between GROUP BY and
4547 ORDER BY. It is applied to the after the grouping calculations have been
4550 having => { 'count_employee' => { '>=', 100 } }
4552 or with an in-place function in which case literal SQL is required:
4554 having => \[ 'count(employee) >= ?', [ count => 100 ] ]
4560 =item Value: (0 | 1)
4564 Set to 1 to automatically generate a L</group_by> clause based on the selection
4565 (including intelligent handling of L</order_by> contents). Note that the group
4566 criteria calculation takes place over the B<final> selection. This includes
4567 any L</+columns>, L</+select> or L</order_by> additions in subsequent
4568 L</search> calls, and standalone columns selected via
4569 L<DBIx::Class::ResultSetColumn> (L</get_column>). A notable exception are the
4570 extra selections specified via L</prefetch> - such selections are explicitly
4571 excluded from group criteria calculations.
4573 If the final ResultSet also explicitly defines a L</group_by> attribute, this
4574 setting is ignored and an appropriate warning is issued.
4580 Adds to the WHERE clause.
4582 # only return rows WHERE deleted IS NULL for all searches
4583 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4585 Can be overridden by passing C<< { where => undef } >> as an attribute
4588 For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
4594 Set to 1 to cache search results. This prevents extra SQL queries if you
4595 revisit rows in your ResultSet:
4597 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4599 while( my $artist = $resultset->next ) {
4603 $rs->first; # without cache, this would issue a query
4605 By default, searches are not cached.
4607 For more examples of using these attributes, see
4608 L<DBIx::Class::Manual::Cookbook>.
4614 =item Value: ( 'update' | 'shared' | \$scalar )
4618 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4619 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4624 DBIx::Class supports arbitrary related data prefetching from multiple related
4625 sources. Any combination of relationship types and column sets are supported.
4626 If L<collapsing|/collapse> is requested, there is an additional requirement of
4627 selecting enough data to make every individual object uniquely identifiable.
4629 Here are some more involved examples, based on the following relationship map:
4632 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4633 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4634 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4636 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4638 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4642 my $rs = $schema->resultset('Tag')->search(
4651 The initial search results in SQL like the following:
4653 SELECT tag.*, cd.*, artist.* FROM tag
4654 JOIN cd ON tag.cd = cd.cdid
4655 JOIN artist ON cd.artist = artist.artistid
4657 L<DBIx::Class> has no need to go back to the database when we access the
4658 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4661 Simple prefetches will be joined automatically, so there is no need
4662 for a C<join> attribute in the above search.
4664 The L</prefetch> attribute can be used with any of the relationship types
4665 and multiple prefetches can be specified together. Below is a more complex
4666 example that prefetches a CD's artist, its liner notes (if present),
4667 the cover image, the tracks on that CD, and the guests on those
4670 my $rs = $schema->resultset('CD')->search(
4674 { artist => 'record_label'}, # belongs_to => belongs_to
4675 'liner_note', # might_have
4676 'cover_image', # has_one
4677 { tracks => 'guests' }, # has_many => has_many
4682 This will produce SQL like the following:
4684 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4688 ON artist.artistid = me.artistid
4689 JOIN record_label record_label
4690 ON record_label.labelid = artist.labelid
4691 LEFT JOIN track tracks
4692 ON tracks.cdid = me.cdid
4693 LEFT JOIN guest guests
4694 ON guests.trackid = track.trackid
4695 LEFT JOIN liner_notes liner_note
4696 ON liner_note.cdid = me.cdid
4697 JOIN cd_artwork cover_image
4698 ON cover_image.cdid = me.cdid
4701 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4702 C<tracks>, and C<guests> of the CD will all be available through the
4703 relationship accessors without the need for additional queries to the
4708 Prefetch does a lot of deep magic. As such, it may not behave exactly
4709 as you might expect.
4715 Prefetch uses the L</cache> to populate the prefetched relationships. This
4716 may or may not be what you want.
4720 If you specify a condition on a prefetched relationship, ONLY those
4721 rows that match the prefetched condition will be fetched into that relationship.
4722 This means that adding prefetch to a search() B<may alter> what is returned by
4723 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4725 my $artist_rs = $schema->resultset('Artist')->search({
4731 my $count = $artist_rs->first->cds->count;
4733 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4735 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4737 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4739 That cmp_ok() may or may not pass depending on the datasets involved. In other
4740 words the C<WHERE> condition would apply to the entire dataset, just like
4741 it would in regular SQL. If you want to add a condition only to the "right side"
4742 of a C<LEFT JOIN> - consider declaring and using a L<relationship with a custom
4743 condition|DBIx::Class::Relationship::Base/condition>
4747 =head1 DBIC BIND VALUES
4749 Because DBIC may need more information to bind values than just the column name
4750 and value itself, it uses a special format for both passing and receiving bind
4751 values. Each bind value should be composed of an arrayref of
4752 C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
4758 If present (in any form), this is what is being passed directly to bind_param.
4759 Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
4760 a single numerical type, while DBD::Pg takes a hashref if bind options.)
4762 If this is specified, all other bind options described below are ignored.
4766 If present, this is used to infer the actual bind attribute by passing to
4767 C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
4768 "data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
4770 Note that the data type is somewhat freeform (hence the sqlt_ prefix);
4771 currently drivers are expected to "Do the Right Thing" when given a common
4772 datatype name. (Not ideal, but that's what we got at this point.)
4776 Currently used to correctly allocate buffers for bind_param_inout().
4777 Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
4778 or to a sensible value based on the "data_type".
4782 Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
4783 explicitly specified they are never overridden). Also used by some weird DBDs,
4784 where the column name should be available at bind_param time (e.g. Oracle).
4788 For backwards compatibility and convenience, the following shortcuts are
4791 [ $name => $val ] === [ { dbic_colname => $name }, $val ]
4792 [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
4793 [ undef, $val ] === [ {}, $val ]
4794 $val === [ {}, $val ]
4796 =head1 AUTHOR AND CONTRIBUTORS
4798 See L<AUTHOR|DBIx::Class/AUTHOR> and L<CONTRIBUTORS|DBIx::Class/CONTRIBUTORS> in DBIx::Class
4802 You may distribute this code under the same terms as Perl itself.