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 'fail_on_internal_wantarray';
11 use Data::Compare (); # no imports!!! guard against insane architecture
12 use Data::Query::Constants;
13 use Data::Query::ExprHelpers;
14 # not importing first() as it will clash with our own method
18 # De-duplication in _merge_attr() is disabled, but left in for reference
19 # (the merger is used for other things that ought not to be de-duped)
20 *__HM_DEDUP = sub () { 0 };
30 # this is real - CDBICompat overrides it with insanity
31 # yes, prototype won't matter, but that's for now ;)
34 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class result_source/);
38 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
42 my $users_rs = $schema->resultset('User');
43 while( $user = $users_rs->next) {
44 print $user->username;
47 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
48 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
52 A ResultSet is an object which stores a set of conditions representing
53 a query. It is the backbone of DBIx::Class (i.e. the really
54 important/useful bit).
56 No SQL is executed on the database when a ResultSet is created, it
57 just stores all the conditions needed to create the query.
59 A basic ResultSet representing the data of an entire table is returned
60 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
61 L<Source|DBIx::Class::Manual::Glossary/Source> name.
63 my $users_rs = $schema->resultset('User');
65 A new ResultSet is returned from calling L</search> on an existing
66 ResultSet. The new one will contain all the conditions of the
67 original, plus any new conditions added in the C<search> call.
69 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
70 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
73 The query that the ResultSet represents is B<only> executed against
74 the database when these methods are called:
75 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
77 If a resultset is used in a numeric context it returns the L</count>.
78 However, if it is used in a boolean context it is B<always> true. So if
79 you want to check if a resultset has any results, you must use C<if $rs
82 =head1 CUSTOM ResultSet CLASSES THAT USE Moose
84 If you want to make your custom ResultSet classes with L<Moose>, use a template
87 package MyApp::Schema::ResultSet::User;
90 use namespace::autoclean;
92 extends 'DBIx::Class::ResultSet';
94 sub BUILDARGS { $_[2] }
98 __PACKAGE__->meta->make_immutable;
102 The L<MooseX::NonMoose> is necessary so that the L<Moose> constructor does not
103 clash with the regular ResultSet constructor. Alternatively, you can use:
105 __PACKAGE__->meta->make_immutable(inline_constructor => 0);
107 The L<BUILDARGS|Moose::Manual::Construction/BUILDARGS> is necessary because the
108 signature of the ResultSet C<new> is C<< ->new($source, \%args) >>.
112 =head2 Chaining resultsets
114 Let's say you've got a query that needs to be run to return some data
115 to the user. But, you have an authorization system in place that
116 prevents certain users from seeing certain information. So, you want
117 to construct the basic query in one method, but add constraints to it in
122 my $request = $self->get_request; # Get a request object somehow.
123 my $schema = $self->result_source->schema;
125 my $cd_rs = $schema->resultset('CD')->search({
126 title => $request->param('title'),
127 year => $request->param('year'),
130 $cd_rs = $self->apply_security_policy( $cd_rs );
132 return $cd_rs->all();
135 sub apply_security_policy {
144 =head3 Resolving conditions and attributes
146 When a resultset is chained from another resultset (e.g.:
147 C<< my $new_rs = $old_rs->search(\%extra_cond, \%attrs) >>), conditions
148 and attributes with the same keys need resolving.
150 If any of L</columns>, L</select>, L</as> are present, they reset the
151 original selection, and start the selection "clean".
153 The L</join>, L</prefetch>, L</+columns>, L</+select>, L</+as> attributes
154 are merged into the existing ones from the original resultset.
156 The L</where> and L</having> attributes, and any search conditions, are
157 merged with an SQL C<AND> to the existing condition from the original
160 All other attributes are overridden by any new ones supplied in the
163 =head2 Multiple queries
165 Since a resultset just defines a query, you can do all sorts of
166 things with it with the same object.
168 # Don't hit the DB yet.
169 my $cd_rs = $schema->resultset('CD')->search({
170 title => 'something',
174 # Each of these hits the DB individually.
175 my $count = $cd_rs->count;
176 my $most_recent = $cd_rs->get_column('date_released')->max();
177 my @records = $cd_rs->all;
179 And it's not just limited to SELECT statements.
185 $cd_rs->create({ artist => 'Fred' });
187 Which is the same as:
189 $schema->resultset('CD')->create({
190 title => 'something',
195 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
203 =item Arguments: L<$source|DBIx::Class::ResultSource>, L<\%attrs?|/ATTRIBUTES>
205 =item Return Value: L<$resultset|/search>
209 The resultset constructor. Takes a source object (usually a
210 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
211 L</ATTRIBUTES> below). Does not perform any queries -- these are
212 executed as needed by the other methods.
214 Generally you never construct a resultset manually. Instead you get one
216 C<< $schema->L<resultset|DBIx::Class::Schema/resultset>('$source_name') >>
217 or C<< $another_resultset->L<search|/search>(...) >> (the later called in
220 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
226 If called on an object, proxies to L</new_result> instead, so
228 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
230 will return a CD object, not a ResultSet, and is equivalent to:
232 my $cd = $schema->resultset('CD')->new_result({ title => 'Spoon' });
234 Please also keep in mind that many internals call L</new_result> directly,
235 so overloading this method with the idea of intercepting new result object
236 creation B<will not work>. See also warning pertaining to L</create>.
244 return $class->new_result(@_) if ref $class;
246 my ($source, $attrs) = @_;
247 $source = $source->resolve
248 if $source->isa('DBIx::Class::ResultSourceHandle');
250 $attrs = { %{$attrs||{}} };
251 delete @{$attrs}{qw(_sqlmaker_select_args _related_results_construction)};
253 if ($attrs->{page}) {
254 $attrs->{rows} ||= 10;
257 $attrs->{alias} ||= 'me';
260 result_source => $source,
261 cond => $attrs->{where},
266 # if there is a dark selector, this means we are already in a
267 # chain and the cleanup/sanification was taken care of by
269 $self->_normalize_selection($attrs)
270 unless $attrs->{_dark_selector};
273 $attrs->{result_class} || $source->result_class
283 =item Arguments: L<$cond|DBIx::Class::SQLMaker> | undef, L<\%attrs?|/ATTRIBUTES>
285 =item Return Value: $resultset (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
289 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
290 my $new_rs = $cd_rs->search({ year => 2005 });
292 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
293 # year = 2005 OR year = 2004
295 In list context, C<< ->all() >> is called implicitly on the resultset, thus
296 returning a list of L<result|DBIx::Class::Manual::ResultClass> objects instead.
297 To avoid that, use L</search_rs>.
299 If you need to pass in additional attributes but no additional condition,
300 call it as C<search(undef, \%attrs)>.
302 # "SELECT name, artistid FROM $artist_table"
303 my @all_artists = $schema->resultset('Artist')->search(undef, {
304 columns => [qw/name artistid/],
307 For a list of attributes that can be passed to C<search>, see
308 L</ATTRIBUTES>. For more examples of using this function, see
309 L<Searching|DBIx::Class::Manual::Cookbook/SEARCHING>. For a complete
310 documentation for the first argument, see L<SQL::Abstract/"WHERE CLAUSES">
311 and its extension L<DBIx::Class::SQLMaker>.
313 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
317 Note that L</search> does not process/deflate any of the values passed in the
318 L<SQL::Abstract>-compatible search condition structure. This is unlike other
319 condition-bound methods L</new_result>, L</create> and L</find>. The user must ensure
320 manually that any value passed to this method will stringify to something the
321 RDBMS knows how to deal with. A notable example is the handling of L<DateTime>
322 objects, for more info see:
323 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
329 my $rs = $self->search_rs( @_ );
332 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_WANTARRAY and my $sog = fail_on_internal_wantarray($rs);
335 elsif (defined wantarray) {
339 # we can be called by a relationship helper, which in
340 # turn may be called in void context due to some braindead
341 # overload or whatever else the user decided to be clever
342 # at this particular day. Thus limit the exception to
343 # external code calls only
344 $self->throw_exception ('->search is *not* a mutator, calling it in void context makes no sense')
345 if (caller)[0] !~ /^\QDBIx::Class::/;
355 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
357 =item Return Value: L<$resultset|/search>
361 This method does the same exact thing as search() except it will
362 always return a resultset, even in list context.
369 my $rsrc = $self->result_source;
370 my ($call_cond, $call_attrs);
372 # Special-case handling for (undef, undef) or (undef)
373 # Note that (foo => undef) is valid deprecated syntax
374 @_ = () if not scalar grep { defined $_ } @_;
380 # fish out attrs in the ($condref, $attr) case
381 elsif (@_ == 2 and ( ! defined $_[0] or (ref $_[0]) ne '') ) {
382 ($call_cond, $call_attrs) = @_;
385 $self->throw_exception('Odd number of arguments to search')
389 carp_unique 'search( %condition ) is deprecated, use search( \%condition ) instead'
390 unless $rsrc->result_class->isa('DBIx::Class::CDBICompat');
392 for my $i (0 .. $#_) {
394 $self->throw_exception ('All keys in condition key/value pairs must be plain scalars')
395 if (! defined $_[$i] or ref $_[$i] ne '');
401 # see if we can keep the cache (no $rs changes)
403 my %safe = (alias => 1, cache => 1);
404 if ( ! List::Util::first { !$safe{$_} } keys %$call_attrs and (
407 ref $call_cond eq 'HASH' && ! keys %$call_cond
409 ref $call_cond eq 'ARRAY' && ! @$call_cond
411 $cache = $self->get_cache;
414 my $old_attrs = { %{$self->{attrs}} };
415 my ($old_having, $old_where) = delete @{$old_attrs}{qw(having where)};
417 my $new_attrs = { %$old_attrs };
419 # take care of call attrs (only if anything is changing)
420 if ($call_attrs and keys %$call_attrs) {
422 # copy for _normalize_selection
423 $call_attrs = { %$call_attrs };
425 my @selector_attrs = qw/select as columns cols +select +as +columns include_columns/;
427 # reset the current selector list if new selectors are supplied
428 if (List::Util::first { exists $call_attrs->{$_} } qw/columns cols select as/) {
429 delete @{$old_attrs}{(@selector_attrs, '_dark_selector')};
432 # Normalize the new selector list (operates on the passed-in attr structure)
433 # Need to do it on every chain instead of only once on _resolved_attrs, in
434 # order to allow detection of empty vs partial 'as'
435 $call_attrs->{_dark_selector} = $old_attrs->{_dark_selector}
436 if $old_attrs->{_dark_selector};
437 $self->_normalize_selection ($call_attrs);
439 # start with blind overwriting merge, exclude selector attrs
440 $new_attrs = { %{$old_attrs}, %{$call_attrs} };
441 delete @{$new_attrs}{@selector_attrs};
443 for (@selector_attrs) {
444 $new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
445 if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
448 # older deprecated name, use only if {columns} is not there
449 if (my $c = delete $new_attrs->{cols}) {
450 carp_unique( "Resultset attribute 'cols' is deprecated, use 'columns' instead" );
451 if ($new_attrs->{columns}) {
452 carp "Resultset specifies both the 'columns' and the legacy 'cols' attributes - ignoring 'cols'";
455 $new_attrs->{columns} = $c;
460 # join/prefetch use their own crazy merging heuristics
461 foreach my $key (qw/join prefetch/) {
462 $new_attrs->{$key} = $self->_merge_joinpref_attr($old_attrs->{$key}, $call_attrs->{$key})
463 if exists $call_attrs->{$key};
466 # stack binds together
467 $new_attrs->{bind} = [ @{ $old_attrs->{bind} || [] }, @{ $call_attrs->{bind} || [] } ];
471 for ($old_where, $call_cond) {
473 $new_attrs->{where} = $self->_stack_cond (
474 $_, $new_attrs->{where}
479 if (defined $old_having) {
480 $new_attrs->{having} = $self->_stack_cond (
481 $old_having, $new_attrs->{having}
485 my $rs = (ref $self)->new($rsrc, $new_attrs);
487 $rs->set_cache($cache) if ($cache);
493 sub _normalize_selection {
494 my ($self, $attrs) = @_;
497 if ( exists $attrs->{include_columns} ) {
498 carp_unique( "Resultset attribute 'include_columns' is deprecated, use '+columns' instead" );
499 $attrs->{'+columns'} = $self->_merge_attr(
500 $attrs->{'+columns'}, delete $attrs->{include_columns}
504 # columns are always placed first, however
506 # Keep the X vs +X separation until _resolved_attrs time - this allows to
507 # delay the decision on whether to use a default select list ($rsrc->columns)
508 # allowing stuff like the remove_columns helper to work
510 # select/as +select/+as pairs need special handling - the amount of select/as
511 # elements in each pair does *not* have to be equal (think multicolumn
512 # selectors like distinct(foo, bar) ). If the selector is bare (no 'as'
513 # supplied at all) - try to infer the alias, either from the -as parameter
514 # of the selector spec, or use the parameter whole if it looks like a column
515 # name (ugly legacy heuristic). If all fails - leave the selector bare (which
516 # is ok as well), but make sure no more additions to the 'as' chain take place
517 for my $pref ('', '+') {
519 my ($sel, $as) = map {
520 my $key = "${pref}${_}";
522 my $val = [ ref $attrs->{$key} eq 'ARRAY'
524 : $attrs->{$key} || ()
526 delete $attrs->{$key};
530 if (! @$as and ! @$sel ) {
533 elsif (@$as and ! @$sel) {
534 $self->throw_exception(
535 "Unable to handle ${pref}as specification (@$as) without a corresponding ${pref}select"
539 # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
540 # if any @$as has been supplied we assume the user knows what (s)he is doing
541 # and blindly keep stacking up pieces
542 unless ($attrs->{_dark_selector}) {
545 if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
546 push @$as, $_->{-as};
548 # assume any plain no-space, no-parenthesis string to be a column spec
549 # FIXME - this is retarded but is necessary to support shit like 'count(foo)'
550 elsif ( ! ref $_ and $_ =~ /^ [^\s\(\)]+ $/x) {
553 # if all else fails - raise a flag that no more aliasing will be allowed
555 $attrs->{_dark_selector} = {
557 string => ($dark_sel_dumper ||= do {
558 require Data::Dumper::Concise;
559 Data::Dumper::Concise::DumperObject()->Indent(0);
560 })->Values([$_])->Dump
568 elsif (@$as < @$sel) {
569 $self->throw_exception(
570 "Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
573 elsif ($pref and $attrs->{_dark_selector}) {
574 $self->throw_exception(
575 "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
581 $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
582 $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
587 my ($self, $left, $right) = @_;
589 # collapse single element top-level conditions
590 # (single pass only, unlikely to need recursion)
591 for ($left, $right) {
592 if (ref $_ eq 'ARRAY') {
600 elsif (ref $_ eq 'HASH') {
601 my ($first, $more) = keys %$_;
604 if (! defined $first) {
608 elsif (! defined $more) {
609 if ($first eq '-and' and ref $_->{'-and'} eq 'HASH') {
612 elsif ($first eq '-or' and ref $_->{'-or'} eq 'ARRAY') {
619 # merge hashes with weeding out of duplicates (simple cases only)
620 if (ref $left eq 'HASH' and ref $right eq 'HASH') {
622 # shallow copy to destroy
623 $right = { %$right };
624 for (grep { exists $right->{$_} } keys %$left) {
625 # the use of eq_deeply here is justified - the rhs of an
626 # expression can contain a lot of twisted weird stuff
627 delete $right->{$_} if Data::Compare::Compare( $left->{$_}, $right->{$_} );
630 $right = undef unless keys %$right;
634 if (defined $left xor defined $right) {
635 return defined $left ? $left : $right;
637 elsif (! defined $left) {
641 return { -and => [ $left, $right ] };
645 =head2 search_literal
647 B<CAVEAT>: C<search_literal> is provided for Class::DBI compatibility and
648 should only be used in that context. C<search_literal> is a convenience
649 method. It is equivalent to calling C<< $schema->search(\[]) >>, but if you
650 want to ensure columns are bound correctly, use L</search>.
652 See L<DBIx::Class::Manual::Cookbook/SEARCHING> and
653 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
654 require C<search_literal>.
658 =item Arguments: $sql_fragment, @standalone_bind_values
660 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
664 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
665 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
667 Pass a literal chunk of SQL to be added to the conditional part of the
670 Example of how to use C<search> instead of C<search_literal>
672 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
673 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
678 my ($self, $sql, @bind) = @_;
680 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
683 return $self->search(\[ $sql, map [ {} => $_ ], @bind ], ($attr || () ));
690 =item Arguments: \%columns_values | @pk_values, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
692 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
696 Finds and returns a single row based on supplied criteria. Takes either a
697 hashref with the same format as L</create> (including inference of foreign
698 keys from related objects), or a list of primary key values in the same
699 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
700 declaration on the L</result_source>.
702 In either case an attempt is made to combine conditions already existing on
703 the resultset with the condition passed to this method.
705 To aid with preparing the correct query for the storage you may supply the
706 C<key> attribute, which is the name of a
707 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
708 unique constraint corresponding to the
709 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
710 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
711 to construct a query that satisfies the named unique constraint fully (
712 non-NULL values for each column member of the constraint) an exception is
715 If no C<key> is specified, the search is carried over all unique constraints
716 which are fully defined by the available condition.
718 If no such constraint is found, C<find> currently defaults to a simple
719 C<< search->(\%column_values) >> which may or may not do what you expect.
720 Note that this fallback behavior may be deprecated in further versions. If
721 you need to search with arbitrary conditions - use L</search>. If the query
722 resulting from this fallback produces more than one row, a warning to the
723 effect is issued, though only the first row is constructed and returned as
726 In addition to C<key>, L</find> recognizes and applies standard
727 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
729 Note that if you have extra concerns about the correctness of the resulting
730 query you need to specify the C<key> attribute and supply the entire condition
731 as an argument to find (since it is not always possible to perform the
732 combination of the resultset condition with the supplied one, especially if
733 the resultset condition contains literal sql).
735 For example, to find a row by its primary key:
737 my $cd = $schema->resultset('CD')->find(5);
739 You can also find a row by a specific unique constraint:
741 my $cd = $schema->resultset('CD')->find(
743 artist => 'Massive Attack',
744 title => 'Mezzanine',
746 { key => 'cd_artist_title' }
749 See also L</find_or_create> and L</update_or_create>.
755 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
757 my $rsrc = $self->result_source;
760 if (exists $attrs->{key}) {
761 $constraint_name = defined $attrs->{key}
763 : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
767 # Parse out the condition from input
770 if (ref $_[0] eq 'HASH') {
771 $call_cond = { %{$_[0]} };
774 # if only values are supplied we need to default to 'primary'
775 $constraint_name = 'primary' unless defined $constraint_name;
777 my @c_cols = $rsrc->unique_constraint_columns($constraint_name);
779 $self->throw_exception(
780 "No constraint columns, maybe a malformed '$constraint_name' constraint?"
783 $self->throw_exception (
784 'find() expects either a column/value hashref, or a list of values '
785 . "corresponding to the columns of the specified unique constraint '$constraint_name'"
786 ) unless @c_cols == @_;
789 @{$call_cond}{@c_cols} = @_;
793 for my $key (keys %$call_cond) {
795 my $keyref = ref($call_cond->{$key})
797 my $relinfo = $rsrc->relationship_info($key)
799 my $val = delete $call_cond->{$key};
801 next if $keyref eq 'ARRAY'; # has_many for multi_create
803 my $rel_q = $rsrc->_resolve_condition(
804 $relinfo->{cond}, $val, $key, $key
806 die "Can't handle complex relationship conditions in find" if ref($rel_q) ne 'HASH';
807 @related{keys %$rel_q} = values %$rel_q;
811 # relationship conditions take precedence (?)
812 @{$call_cond}{keys %related} = values %related;
814 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
816 if (defined $constraint_name) {
817 $final_cond = $self->_qualify_cond_columns (
819 $self->_build_unique_cond (
827 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
828 # This means that we got here after a merger of relationship conditions
829 # in ::Relationship::Base::search_related (the row method), and furthermore
830 # the relationship is of the 'single' type. This means that the condition
831 # provided by the relationship (already attached to $self) is sufficient,
832 # as there can be only one row in the database that would satisfy the
836 # no key was specified - fall down to heuristics mode:
837 # run through all unique queries registered on the resultset, and
838 # 'OR' all qualifying queries together
839 my (@unique_queries, %seen_column_combinations);
840 for my $c_name ($rsrc->unique_constraint_names) {
841 next if $seen_column_combinations{
842 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
845 push @unique_queries, try {
846 $self->_build_unique_cond ($c_name, $call_cond, 'croak_on_nulls')
850 $final_cond = @unique_queries
851 ? [ map { $self->_qualify_cond_columns($_, $alias) } @unique_queries ]
852 : $self->_non_unique_find_fallback ($call_cond, $attrs)
856 # Run the query, passing the result_class since it should propagate for find
857 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
858 if ($rs->_resolved_attrs->{collapse}) {
860 carp "Query returned more than one row" if $rs->next;
868 # This is a stop-gap method as agreed during the discussion on find() cleanup:
869 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
871 # It is invoked when find() is called in legacy-mode with insufficiently-unique
872 # condition. It is provided for overrides until a saner way forward is devised
874 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
875 # the road. Please adjust your tests accordingly to catch this situation early
876 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
878 # The method will not be removed without an adequately complete replacement
879 # for strict-mode enforcement
880 sub _non_unique_find_fallback {
881 my ($self, $cond, $attrs) = @_;
883 return $self->_qualify_cond_columns(
885 exists $attrs->{alias}
887 : $self->{attrs}{alias}
892 sub _qualify_cond_columns {
893 my ($self, $cond, $alias) = @_;
895 my %aliased = %$cond;
896 for (keys %aliased) {
897 $aliased{"$alias.$_"} = delete $aliased{$_}
904 sub _build_unique_cond {
905 my ($self, $constraint_name, $extra_cond, $croak_on_null) = @_;
907 my @c_cols = $self->result_source->unique_constraint_columns($constraint_name);
909 # combination may fail if $self->{cond} is non-trivial
910 my ($final_cond) = try {
911 $self->_merge_with_rscond ($extra_cond)
916 # trim out everything not in $columns
917 $final_cond = { map {
918 exists $final_cond->{$_}
919 ? ( $_ => $final_cond->{$_} )
923 if (my @missing = grep
924 { ! ($croak_on_null ? defined $final_cond->{$_} : exists $final_cond->{$_}) }
927 $self->throw_exception( sprintf ( "Unable to satisfy requested constraint '%s', no values for column(s): %s",
929 join (', ', map { "'$_'" } @missing),
936 !$ENV{DBIC_NULLABLE_KEY_NOWARN}
938 my @undefs = sort grep { ! defined $final_cond->{$_} } (keys %$final_cond)
940 carp_unique ( sprintf (
941 "NULL/undef values supplied for requested unique constraint '%s' (NULL "
942 . 'values in column(s): %s). This is almost certainly not what you wanted, '
943 . 'though you can set DBIC_NULLABLE_KEY_NOWARN to disable this warning.',
945 join (', ', map { "'$_'" } @undefs),
952 =head2 search_related
956 =item Arguments: $rel_name, $cond?, L<\%attrs?|/ATTRIBUTES>
958 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
962 $new_rs = $cd_rs->search_related('artist', {
966 Searches the specified relationship, optionally specifying a condition and
967 attributes for matching records. See L</ATTRIBUTES> for more information.
969 In list context, C<< ->all() >> is called implicitly on the resultset, thus
970 returning a list of result objects instead. To avoid that, use L</search_related_rs>.
972 See also L</search_related_rs>.
977 return shift->related_resultset(shift)->search(@_);
980 =head2 search_related_rs
982 This method works exactly the same as search_related, except that
983 it guarantees a resultset, even in list context.
987 sub search_related_rs {
988 return shift->related_resultset(shift)->search_rs(@_);
995 =item Arguments: none
997 =item Return Value: L<$cursor|DBIx::Class::Cursor>
1001 Returns a storage-driven cursor to the given resultset. See
1002 L<DBIx::Class::Cursor> for more information.
1009 return $self->{cursor} ||= do {
1010 my $attrs = $self->_resolved_attrs;
1011 $self->result_source->storage->select(
1012 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
1021 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1023 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1027 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1029 Inflates the first result without creating a cursor if the resultset has
1030 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1033 While this method can take an optional search condition (just like L</search>)
1034 being a fast-code-path it does not recognize search attributes. If you need to
1035 add extra joins or similar, call L</search> and then chain-call L</single> on the
1036 L<DBIx::Class::ResultSet> returned.
1042 As of 0.08100, this method enforces the assumption that the preceding
1043 query returns only one row. If more than one row is returned, you will receive
1046 Query returned more than one row
1048 In this case, you should be using L</next> or L</find> instead, or if you really
1049 know what you are doing, use the L</rows> attribute to explicitly limit the size
1052 This method will also throw an exception if it is called on a resultset prefetching
1053 has_many, as such a prefetch implies fetching multiple rows from the database in
1054 order to assemble the resulting object.
1061 my ($self, $where) = @_;
1063 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1066 my $attrs = { %{$self->_resolved_attrs} };
1068 $self->throw_exception(
1069 'single() can not be used on resultsets collapsing a has_many. Use find( \%cond ) or next() instead'
1070 ) if $attrs->{collapse};
1073 if (defined $attrs->{where}) {
1076 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1077 $where, delete $attrs->{where} ]
1080 $attrs->{where} = $where;
1084 my $data = [ $self->result_source->storage->select_single(
1085 $attrs->{from}, $attrs->{select},
1086 $attrs->{where}, $attrs
1089 return undef unless @$data;
1090 $self->{_stashed_rows} = [ $data ];
1091 $self->_construct_results->[0];
1097 # Recursively collapse the query, accumulating values for each column.
1099 sub _collapse_query {
1100 my ($self, $query, $collapsed) = @_;
1104 if (ref $query eq 'ARRAY') {
1105 foreach my $subquery (@$query) {
1106 next unless ref $subquery; # -or
1107 $collapsed = $self->_collapse_query($subquery, $collapsed);
1110 elsif (ref $query eq 'HASH') {
1111 if (keys %$query and (keys %$query)[0] eq '-and') {
1112 foreach my $subquery (@{$query->{-and}}) {
1113 $collapsed = $self->_collapse_query($subquery, $collapsed);
1117 foreach my $col (keys %$query) {
1118 my $value = $query->{$col};
1119 $collapsed->{$col}{$value}++;
1131 =item Arguments: L<$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 $attrs->{_ordered_for_collapse} = (
1327 ->_main_source_order_by_portion_is_stable($rsrc, $attrs->{order_by}, $attrs->{where})
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->{_sqlmaker_select_args}[3]{_aliastypes} ) {
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 (! $attrs->{_related_results_construction}) {
1412 # construct a much simpler array->hash folder for the one-table cases right here
1413 if ($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 (@$rows < 60) {
1426 for my $r (@$rows) {
1427 $r = $inflator_cref->($res_class, $rsrc, { map { $infmap->[$_] => $r->[$_] } (0..$#$infmap) } );
1432 '$_ = $inflator_cref->($res_class, $rsrc, { %s }) for @$rows',
1433 join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap )
1439 $self->{_result_inflator}{is_hri} ? 'hri'
1440 : $self->{_result_inflator}{is_core_row} ? 'classic_pruning'
1441 : 'classic_nonpruning'
1444 # $args and $attrs to _mk_row_parser are separated to delineate what is
1445 # core collapser stuff and what is dbic $rs specific
1446 @{$self->{_row_parser}{$parser_type}}{qw(cref nullcheck)} = $rsrc->_mk_row_parser({
1448 inflate_map => $infmap,
1449 collapse => $attrs->{collapse},
1450 premultiplied => $attrs->{_main_source_premultiplied},
1451 hri_style => $self->{_result_inflator}{is_hri},
1452 prune_null_branches => $self->{_result_inflator}{is_hri} || $self->{_result_inflator}{is_core_row},
1453 }, $attrs) unless $self->{_row_parser}{$parser_type}{cref};
1455 # column_info metadata historically hasn't been too reliable.
1456 # We need to start fixing this somehow (the collapse resolver
1457 # can't work without it). Add an explicit check for the *main*
1458 # result, hopefully this will gradually weed out such errors
1460 # FIXME - this is a temporary kludge that reduces performance
1461 # It is however necessary for the time being
1462 my ($unrolled_non_null_cols_to_check, $err);
1464 if (my $check_non_null_cols = $self->{_row_parser}{$parser_type}{nullcheck} ) {
1467 'Collapse aborted due to invalid ResultSource metadata - the following '
1468 . 'selections are declared non-nullable but NULLs were retrieved: '
1472 COL: for my $i (@$check_non_null_cols) {
1473 ! defined $_->[$i] and push @violating_idx, $i and next COL for @$rows;
1476 $self->throw_exception( $err . join (', ', map { "'$infmap->[$_]'" } @violating_idx ) )
1479 $unrolled_non_null_cols_to_check = join (',', @$check_non_null_cols);
1483 ($did_fetch_all or ! $attrs->{collapse}) ? undef
1484 : defined $unrolled_non_null_cols_to_check ? eval sprintf <<'EOS', $unrolled_non_null_cols_to_check
1486 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1487 my @r = $cursor->next or return;
1488 if (my @violating_idx = grep { ! defined $r[$_] } (%s) ) {
1489 $self->throw_exception( $err . join (', ', map { "'$infmap->[$_]'" } @violating_idx ) )
1495 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1496 my @r = $cursor->next or return;
1501 $self->{_row_parser}{$parser_type}{cref}->(
1503 $next_cref ? ( $next_cref, $self->{_stashed_rows} = [] ) : (),
1506 # Special-case multi-object HRI - there is no $inflator_cref pass
1507 unless ($self->{_result_inflator}{is_hri}) {
1508 $_ = $inflator_cref->($res_class, $rsrc, @$_) for @$rows
1512 # The @$rows check seems odd at first - why wouldn't we want to warn
1513 # regardless? The issue is things like find() etc, where the user
1514 # *knows* only one result will come back. In these cases the ->all
1515 # is not a pessimization, but rather something we actually want
1517 'Unable to properly collapse has_many results in iterator mode due '
1518 . 'to order criteria - performed an eager cursor slurp underneath. '
1519 . 'Consider using ->all() instead'
1520 ) if ( ! $fetch_all and @$rows > 1 );
1525 =head2 result_source
1529 =item Arguments: L<$result_source?|DBIx::Class::ResultSource>
1531 =item Return Value: L<$result_source|DBIx::Class::ResultSource>
1535 An accessor for the primary ResultSource object from which this ResultSet
1542 =item Arguments: $result_class?
1544 =item Return Value: $result_class
1548 An accessor for the class to use when creating result objects. Defaults to
1549 C<< result_source->result_class >> - which in most cases is the name of the
1550 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1552 Note that changing the result_class will also remove any components
1553 that were originally loaded in the source class via
1554 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1555 in the original source class will not run.
1560 my ($self, $result_class) = @_;
1561 if ($result_class) {
1563 # don't fire this for an object
1564 $self->ensure_class_loaded($result_class)
1565 unless ref($result_class);
1567 if ($self->get_cache) {
1568 carp_unique('Changing the result_class of a ResultSet instance with cached results is a noop - the cache contents will not be altered');
1570 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1571 elsif ($self->{cursor} && $self->{cursor}{_pos}) {
1572 $self->throw_exception('Changing the result_class of a ResultSet instance with an active cursor is not supported');
1575 $self->_result_class($result_class);
1577 delete $self->{_result_inflator};
1579 $self->_result_class;
1586 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1588 =item Return Value: $count
1592 Performs an SQL C<COUNT> with the same query as the resultset was built
1593 with to find the number of elements. Passing arguments is equivalent to
1594 C<< $rs->search ($cond, \%attrs)->count >>
1600 return $self->search(@_)->count if @_ and defined $_[0];
1601 return scalar @{ $self->get_cache } if $self->get_cache;
1603 my $attrs = { %{ $self->_resolved_attrs } };
1605 # this is a little optimization - it is faster to do the limit
1606 # adjustments in software, instead of a subquery
1607 my ($rows, $offset) = delete @{$attrs}{qw/rows offset/};
1610 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1611 $crs = $self->_count_subq_rs ($attrs);
1614 $crs = $self->_count_rs ($attrs);
1616 my $count = $crs->next;
1618 $count -= $offset if $offset;
1619 $count = $rows if $rows and $rows < $count;
1620 $count = 0 if ($count < 0);
1629 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1631 =item Return Value: L<$count_rs|DBIx::Class::ResultSetColumn>
1635 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1636 This can be very handy for subqueries:
1638 ->search( { amount => $some_rs->count_rs->as_query } )
1640 As with regular resultsets the SQL query will be executed only after
1641 the resultset is accessed via L</next> or L</all>. That would return
1642 the same single value obtainable via L</count>.
1648 return $self->search(@_)->count_rs if @_;
1650 # this may look like a lack of abstraction (count() does about the same)
1651 # but in fact an _rs *must* use a subquery for the limits, as the
1652 # software based limiting can not be ported if this $rs is to be used
1653 # in a subquery itself (i.e. ->as_query)
1654 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1655 return $self->_count_subq_rs($self->{_attrs});
1658 return $self->_count_rs($self->{_attrs});
1663 # returns a ResultSetColumn object tied to the count query
1666 my ($self, $attrs) = @_;
1668 my $rsrc = $self->result_source;
1670 my $tmp_attrs = { %$attrs };
1671 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1672 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1674 # overwrite the selector (supplied by the storage)
1675 $rsrc->resultset_class->new($rsrc, {
1677 select => $rsrc->storage->_count_select ($rsrc, $attrs),
1679 })->get_column ('count');
1683 # same as above but uses a subquery
1685 sub _count_subq_rs {
1686 my ($self, $attrs) = @_;
1688 my $rsrc = $self->result_source;
1690 my $sub_attrs = { %$attrs };
1691 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1692 delete @{$sub_attrs}{qw/collapse columns as select order_by for/};
1694 # if we multi-prefetch we group_by something unique, as this is what we would
1695 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1696 if ( $attrs->{collapse} ) {
1697 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1698 $rsrc->_identifying_column_set || $self->throw_exception(
1699 'Unable to construct a unique group_by criteria properly collapsing the '
1700 . 'has_many prefetch before count()'
1705 # Calculate subquery selector
1706 if (my $g = $sub_attrs->{group_by}) {
1708 my $sql_maker = $rsrc->storage->sql_maker;
1710 # necessary as the group_by may refer to aliased functions
1712 for my $sel (@{$attrs->{select}}) {
1713 $sel_index->{$sel->{-as}} = $sel
1714 if (ref $sel eq 'HASH' and $sel->{-as});
1717 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1718 # also look for named aggregates referred in the having clause
1719 # having often contains scalarrefs - thus parse it out entirely
1721 if ($attrs->{having}) {
1722 local $sql_maker->{having_bind};
1723 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1724 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1725 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1726 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1727 # if we don't unset it we screw up retarded but unfortunately working
1728 # 'MAX(foo.bar)' => { '>', 3 }
1729 $sql_maker->{name_sep} = '';
1732 $sql_maker->clear_renderer;
1733 $sql_maker->clear_converter;
1735 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1737 my $having_sql = $sql_maker->_render_sqla(where => $attrs->{having});
1739 $sql_maker->clear_renderer;
1740 $sql_maker->clear_converter;
1744 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1745 # and if all fails for an utterly naive quoted scalar-with-function
1746 while ($having_sql =~ /
1747 (?: $rquote $sep)? $lquote (.+?) $rquote
1749 [\s,] \w+ \. (\w+) [\s,]
1751 [\s,] $lquote (.+?) $rquote [\s,]
1753 my $part = $1 || $2 || $3; # one of them matched if we got here
1754 unless ($seen_having{$part}++) {
1761 my $colpiece = $sel_index->{$_} || $_;
1763 # unqualify join-based group_by's. Arcane but possible query
1764 # also horrible horrible hack to alias a column (not a func.)
1765 # (probably need to introduce SQLA syntax)
1766 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1769 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1771 push @{$sub_attrs->{select}}, $colpiece;
1775 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1776 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1779 return $rsrc->resultset_class
1780 ->new ($rsrc, $sub_attrs)
1782 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1783 ->get_column ('count');
1787 =head2 count_literal
1789 B<CAVEAT>: C<count_literal> is provided for Class::DBI compatibility and
1790 should only be used in that context. See L</search_literal> for further info.
1794 =item Arguments: $sql_fragment, @standalone_bind_values
1796 =item Return Value: $count
1800 Counts the results in a literal query. Equivalent to calling L</search_literal>
1801 with the passed arguments, then L</count>.
1805 sub count_literal { shift->search_literal(@_)->count; }
1811 =item Arguments: none
1813 =item Return Value: L<@result_objs|DBIx::Class::Manual::ResultClass>
1817 Returns all elements in the resultset.
1824 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1827 delete @{$self}{qw/_stashed_rows _stashed_results/};
1829 if (my $c = $self->get_cache) {
1833 $self->cursor->reset;
1835 my $objs = $self->_construct_results('fetch_all') || [];
1837 $self->set_cache($objs) if $self->{attrs}{cache};
1846 =item Arguments: none
1848 =item Return Value: $self
1852 Resets the resultset's cursor, so you can iterate through the elements again.
1853 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1861 delete @{$self}{qw/_stashed_rows _stashed_results/};
1862 $self->{all_cache_position} = 0;
1863 $self->cursor->reset;
1871 =item Arguments: none
1873 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1877 L<Resets|/reset> the resultset (causing a fresh query to storage) and returns
1878 an object for the first result (or C<undef> if the resultset is empty).
1883 return $_[0]->reset->next;
1889 # Determines whether and what type of subquery is required for the $rs operation.
1890 # If grouping is necessary either supplies its own, or verifies the current one
1891 # After all is done delegates to the proper storage method.
1893 sub _rs_update_delete {
1894 my ($self, $op, $values) = @_;
1896 my $rsrc = $self->result_source;
1897 my $storage = $rsrc->schema->storage;
1899 my $attrs = { %{$self->_resolved_attrs} };
1901 my $join_classifications;
1902 my ($existing_group_by) = delete @{$attrs}{qw(group_by _grouped_by_distinct)};
1904 # do we need a subquery for any reason?
1906 defined $existing_group_by
1908 # if {from} is unparseable wrap a subq
1909 ref($attrs->{from}) ne 'ARRAY'
1911 # limits call for a subq
1912 $self->_has_resolved_attr(qw/rows offset/)
1915 # simplify the joinmap, so we can further decide if a subq is necessary
1916 if (!$needs_subq and @{$attrs->{from}} > 1) {
1918 ($attrs->{from}, $join_classifications) =
1919 $storage->_prune_unused_joins ($attrs);
1921 # any non-pruneable non-local restricting joins imply subq
1922 $needs_subq = defined List::Util::first { $_ ne $attrs->{alias} } keys %{ $join_classifications->{restricting} || {} };
1925 # check if the head is composite (by now all joins are thrown out unless $needs_subq)
1927 (ref $attrs->{from}[0]) ne 'HASH'
1929 ref $attrs->{from}[0]{ $attrs->{from}[0]{-alias} }
1933 # do we need anything like a subquery?
1934 if (! $needs_subq) {
1935 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1936 # a condition containing 'me' or other table prefixes will not work
1937 # at all - so we convert the WHERE to a dq tree now, dequalify all
1938 # identifiers found therein via a scan across the tree, and then use
1939 # \{} style to pass the result onwards for use in the final query
1940 if ($self->{cond}) {
1942 my $converter = $rsrc->storage->sql_maker->converter;
1944 DQ_IDENTIFIER ,=> sub { $_ = [ $_->[-1] ] for $_[0]->{elements} }
1945 }, my $where_dq = $converter->_where_to_dq($self->{cond}));
1951 # we got this far - means it is time to wrap a subquery
1952 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1954 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1960 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1961 delete $attrs->{$_} for qw/select as collapse/;
1962 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1964 # this will be consumed by the pruner waaaaay down the stack
1965 $attrs->{_force_prune_multiplying_joins} = 1;
1967 my $subrs = (ref $self)->new($rsrc, $attrs);
1969 if (@$idcols == 1) {
1970 $cond = { $idcols->[0] => { -in => \$subrs->_as_select_dq } };
1972 elsif ($storage->_use_multicolumn_in) {
1973 # no syntax for calling this properly yet
1974 # !!! EXPERIMENTAL API !!! WILL CHANGE !!!
1975 my $left = $storage->sql_maker->_render_sqla(select_select => $idcols);
1976 $left =~ s/^SELECT //i;
1977 my $right = $storage->sql_maker
1979 ->_literal_to_dq(${$subrs->as_query});
1981 { 'SQL.Naive' => 'in' },
1982 [ Literal(SQL => "( $left )"), $right ],
1986 # if all else fails - get all primary keys and operate over a ORed set
1987 # wrap in a transaction for consistency
1988 # this is where the group_by/multiplication starts to matter
1992 # we do not need to check pre-multipliers, since if the premulti is there, its
1993 # parent (who is multi) will be there too
1994 keys %{ $join_classifications->{multiplying} || {} }
1996 # make sure if there is a supplied group_by it matches the columns compiled above
1997 # perfectly. Anything else can not be sanely executed on most databases so croak
1998 # right then and there
1999 if ($existing_group_by) {
2000 my @current_group_by = map
2001 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
2006 join ("\x00", sort @current_group_by)
2008 join ("\x00", sort @{$attrs->{columns}} )
2010 $self->throw_exception (
2011 "You have just attempted a $op operation on a resultset which does group_by"
2012 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
2013 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
2014 . ' kind of queries. Please retry the operation with a modified group_by or'
2015 . ' without using one at all.'
2020 $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
2023 $guard = $storage->txn_scope_guard;
2026 for my $row ($subrs->cursor->all) {
2028 { $idcols->[$_] => $row->[$_] }
2035 my $res = $storage->$op (
2037 $op eq 'update' ? $values : (),
2041 $guard->commit if $guard;
2050 =item Arguments: \%values
2052 =item Return Value: $underlying_storage_rv
2056 Sets the specified columns in the resultset to the supplied values in a
2057 single query. Note that this will not run any accessor/set_column/update
2058 triggers, nor will it update any result object instances derived from this
2059 resultset (this includes the contents of the L<resultset cache|/set_cache>
2060 if any). See L</update_all> if you need to execute any on-update
2061 triggers or cascades defined either by you or a
2062 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2064 The return value is a pass through of what the underlying
2065 storage backend returned, and may vary. See L<DBI/execute> for the most
2070 Note that L</update> does not process/deflate any of the values passed in.
2071 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
2072 ensure manually that any value passed to this method will stringify to
2073 something the RDBMS knows how to deal with. A notable example is the
2074 handling of L<DateTime> objects, for more info see:
2075 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
2080 my ($self, $values) = @_;
2081 $self->throw_exception('Values for update must be a hash')
2082 unless ref $values eq 'HASH';
2084 return $self->_rs_update_delete ('update', $values);
2091 =item Arguments: \%values
2093 =item Return Value: 1
2097 Fetches all objects and updates them one at a time via
2098 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
2099 triggers, while L</update> will not.
2104 my ($self, $values) = @_;
2105 $self->throw_exception('Values for update_all must be a hash')
2106 unless ref $values eq 'HASH';
2108 my $guard = $self->result_source->schema->txn_scope_guard;
2109 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
2118 =item Arguments: none
2120 =item Return Value: $underlying_storage_rv
2124 Deletes the rows matching this resultset in a single query. Note that this
2125 will not run any delete triggers, nor will it alter the
2126 L<in_storage|DBIx::Class::Row/in_storage> status of any result object instances
2127 derived from this resultset (this includes the contents of the
2128 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
2129 execute any on-delete triggers or cascades defined either by you or a
2130 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2132 The return value is a pass through of what the underlying storage backend
2133 returned, and may vary. See L<DBI/execute> for the most common case.
2139 $self->throw_exception('delete does not accept any arguments')
2142 return $self->_rs_update_delete ('delete');
2149 =item Arguments: none
2151 =item Return Value: 1
2155 Fetches all objects and deletes them one at a time via
2156 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2157 triggers, while L</delete> will not.
2163 $self->throw_exception('delete_all does not accept any arguments')
2166 my $guard = $self->result_source->schema->txn_scope_guard;
2167 $_->delete for $self->all;
2176 =item Arguments: [ \@column_list, \@row_values+ ] | [ \%col_data+ ]
2178 =item Return Value: L<\@result_objects|DBIx::Class::Manual::ResultClass> (scalar context) | L<@result_objects|DBIx::Class::Manual::ResultClass> (list context)
2182 Accepts either an arrayref of hashrefs or alternatively an arrayref of
2189 The context of this method call has an important effect on what is
2190 submitted to storage. In void context data is fed directly to fastpath
2191 insertion routines provided by the underlying storage (most often
2192 L<DBI/execute_for_fetch>), bypassing the L<new|DBIx::Class::Row/new> and
2193 L<insert|DBIx::Class::Row/insert> calls on the
2194 L<Result|DBIx::Class::Manual::ResultClass> class, including any
2195 augmentation of these methods provided by components. For example if you
2196 are using something like L<DBIx::Class::UUIDColumns> to create primary
2197 keys for you, you will find that your PKs are empty. In this case you
2198 will have to explicitly force scalar or list context in order to create
2203 In non-void (scalar or list) context, this method is simply a wrapper
2204 for L</create>. Depending on list or scalar context either a list of
2205 L<Result|DBIx::Class::Manual::ResultClass> objects or an arrayref
2206 containing these objects is returned.
2208 When supplying data in "arrayref of arrayrefs" invocation style, the
2209 first element should be a list of column names and each subsequent
2210 element should be a data value in the earlier specified column order.
2213 $schema->resultset("Artist")->populate([
2214 [ qw( artistid name ) ],
2215 [ 100, 'A Formally Unknown Singer' ],
2216 [ 101, 'A singer that jumped the shark two albums ago' ],
2217 [ 102, 'An actually cool singer' ],
2220 For the arrayref of hashrefs style each hashref should be a structure
2221 suitable for passing to L</create>. Multi-create is also permitted with
2224 $schema->resultset("Artist")->populate([
2225 { artistid => 4, name => 'Manufactured Crap', cds => [
2226 { title => 'My First CD', year => 2006 },
2227 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2230 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2231 { title => 'My parents sold me to a record company', year => 2005 },
2232 { title => 'Why Am I So Ugly?', year => 2006 },
2233 { title => 'I Got Surgery and am now Popular', year => 2007 }
2238 If you attempt a void-context multi-create as in the example above (each
2239 Artist also has the related list of CDs), and B<do not> supply the
2240 necessary autoinc foreign key information, this method will proxy to the
2241 less efficient L</create>, and then throw the Result objects away. In this
2242 case there are obviously no benefits to using this method over L</create>.
2249 # cruft placed in standalone method
2250 my $data = $self->_normalize_populate_args(@_);
2252 return unless @$data;
2254 if(defined wantarray) {
2255 my @created = map { $self->create($_) } @$data;
2256 return wantarray ? @created : \@created;
2259 my $first = $data->[0];
2261 # if a column is a registered relationship, and is a non-blessed hash/array, consider
2262 # it relationship data
2263 my (@rels, @columns);
2264 my $rsrc = $self->result_source;
2265 my $rels = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2266 for (keys %$first) {
2267 my $ref = ref $first->{$_};
2268 $rels->{$_} && ($ref eq 'ARRAY' or $ref eq 'HASH')
2274 my @pks = $rsrc->primary_columns;
2276 ## do the belongs_to relationships
2277 foreach my $index (0..$#$data) {
2279 # delegate to create() for any dataset without primary keys with specified relationships
2280 if (grep { !defined $data->[$index]->{$_} } @pks ) {
2282 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
2283 my @ret = $self->populate($data);
2289 foreach my $rel (@rels) {
2290 next unless ref $data->[$index]->{$rel} eq "HASH";
2291 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
2292 my ($reverse_relname, $reverse_relinfo) = %{$rsrc->reverse_relationship_info($rel)};
2293 my $related = $result->result_source->_resolve_condition(
2294 $reverse_relinfo->{cond},
2300 delete $data->[$index]->{$rel};
2301 $data->[$index] = {%{$data->[$index]}, %$related};
2303 push @columns, keys %$related if $index == 0;
2307 ## inherit the data locked in the conditions of the resultset
2308 my ($rs_data) = $self->_merge_with_rscond({});
2309 delete @{$rs_data}{@columns};
2311 ## do bulk insert on current row
2312 $rsrc->storage->insert_bulk(
2314 [@columns, keys %$rs_data],
2315 [ map { [ @$_{@columns}, values %$rs_data ] } @$data ],
2318 ## do the has_many relationships
2319 foreach my $item (@$data) {
2323 foreach my $rel (@rels) {
2324 next unless ref $item->{$rel} eq "ARRAY" && @{ $item->{$rel} };
2326 $main_row ||= $self->new_result({map { $_ => $item->{$_} } @pks});
2328 my $child = $main_row->$rel;
2330 my $related = $child->result_source->_resolve_condition(
2331 $rels->{$rel}{cond},
2337 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
2338 my @populate = map { {%$_, %$related} } @rows_to_add;
2340 $child->populate( \@populate );
2347 # populate() arguments went over several incarnations
2348 # What we ultimately support is AoH
2349 sub _normalize_populate_args {
2350 my ($self, $arg) = @_;
2352 if (ref $arg eq 'ARRAY') {
2356 elsif (ref $arg->[0] eq 'HASH') {
2359 elsif (ref $arg->[0] eq 'ARRAY') {
2361 my @colnames = @{$arg->[0]};
2362 foreach my $values (@{$arg}[1 .. $#$arg]) {
2363 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
2369 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2376 =item Arguments: none
2378 =item Return Value: L<$pager|Data::Page>
2382 Returns a L<Data::Page> object for the current resultset. Only makes
2383 sense for queries with a C<page> attribute.
2385 To get the full count of entries for a paged resultset, call
2386 C<total_entries> on the L<Data::Page> object.
2393 return $self->{pager} if $self->{pager};
2395 my $attrs = $self->{attrs};
2396 if (!defined $attrs->{page}) {
2397 $self->throw_exception("Can't create pager for non-paged rs");
2399 elsif ($attrs->{page} <= 0) {
2400 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2402 $attrs->{rows} ||= 10;
2404 # throw away the paging flags and re-run the count (possibly
2405 # with a subselect) to get the real total count
2406 my $count_attrs = { %$attrs };
2407 delete @{$count_attrs}{qw/rows offset page pager/};
2409 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2411 require DBIx::Class::ResultSet::Pager;
2412 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2413 sub { $total_rs->count }, #lazy-get the total
2415 $self->{attrs}{page},
2423 =item Arguments: $page_number
2425 =item Return Value: L<$resultset|/search>
2429 Returns a resultset for the $page_number page of the resultset on which page
2430 is called, where each page contains a number of rows equal to the 'rows'
2431 attribute set on the resultset (10 by default).
2436 my ($self, $page) = @_;
2437 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2444 =item Arguments: \%col_data
2446 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2450 Creates a new result object in the resultset's result class and returns
2451 it. The row is not inserted into the database at this point, call
2452 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2453 will tell you whether the result object has been inserted or not.
2455 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2460 my ($self, $values) = @_;
2462 $self->throw_exception( "new_result takes only one argument - a hashref of values" )
2465 $self->throw_exception( "new_result expects a hashref" )
2466 unless (ref $values eq 'HASH');
2468 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2470 my $new = $self->result_class->new({
2472 ( @$cols_from_relations
2473 ? (-cols_from_relations => $cols_from_relations)
2476 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2480 reftype($new) eq 'HASH'
2486 carp_unique (sprintf (
2487 "%s->new returned a blessed empty hashref - a strong indicator something is wrong with its inheritance chain",
2488 $self->result_class,
2495 # _merge_with_rscond
2497 # Takes a simple hash of K/V data and returns its copy merged with the
2498 # condition already present on the resultset. Additionally returns an
2499 # arrayref of value/condition names, which were inferred from related
2500 # objects (this is needed for in-memory related objects)
2501 sub _merge_with_rscond {
2502 my ($self, $data) = @_;
2504 my (%new_data, @cols_from_relations);
2506 my $alias = $self->{attrs}{alias};
2508 if (! defined $self->{cond}) {
2509 # just massage $data below
2511 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
2512 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
2513 @cols_from_relations = keys %new_data;
2515 elsif (ref $self->{cond} ne 'HASH') {
2516 $self->throw_exception(
2517 "Can't abstract implicit construct, resultset condition not a hash"
2521 # precedence must be given to passed values over values inherited from
2522 # the cond, so the order here is important.
2523 my $collapsed_cond = $self->_collapse_cond($self->{cond});
2524 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
2526 while ( my($col, $value) = each %implied ) {
2527 my $vref = ref $value;
2533 (keys %$value)[0] eq '='
2535 $new_data{$col} = $value->{'='};
2537 elsif( !$vref or $vref eq 'SCALAR' or blessed($value) ) {
2538 $new_data{$col} = $value;
2545 %{ $self->_remove_alias($data, $alias) },
2548 return (\%new_data, \@cols_from_relations);
2551 # _has_resolved_attr
2553 # determines if the resultset defines at least one
2554 # of the attributes supplied
2556 # used to determine if a subquery is necessary
2558 # supports some virtual attributes:
2560 # This will scan for any joins being present on the resultset.
2561 # It is not a mere key-search but a deep inspection of {from}
2564 sub _has_resolved_attr {
2565 my ($self, @attr_names) = @_;
2567 my $attrs = $self->_resolved_attrs;
2571 for my $n (@attr_names) {
2572 if (grep { $n eq $_ } (qw/-join/) ) {
2573 $extra_checks{$n}++;
2577 my $attr = $attrs->{$n};
2579 next if not defined $attr;
2581 if (ref $attr eq 'HASH') {
2582 return 1 if keys %$attr;
2584 elsif (ref $attr eq 'ARRAY') {
2592 # a resolved join is expressed as a multi-level from
2594 $extra_checks{-join}
2596 ref $attrs->{from} eq 'ARRAY'
2598 @{$attrs->{from}} > 1
2606 # Recursively collapse the condition.
2608 sub _collapse_cond {
2609 my ($self, $cond, $collapsed) = @_;
2613 if (ref $cond eq 'ARRAY') {
2614 foreach my $subcond (@$cond) {
2615 next unless ref $subcond; # -or
2616 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2619 elsif (ref $cond eq 'HASH') {
2620 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2621 foreach my $subcond (@{$cond->{-and}}) {
2622 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2626 foreach my $col (keys %$cond) {
2627 my $value = $cond->{$col};
2628 $collapsed->{$col} = $value;
2638 # Remove the specified alias from the specified query hash. A copy is made so
2639 # the original query is not modified.
2642 my ($self, $query, $alias) = @_;
2644 my %orig = %{ $query || {} };
2647 foreach my $key (keys %orig) {
2649 $unaliased{$key} = $orig{$key};
2652 $unaliased{$1} = $orig{$key}
2653 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2663 =item Arguments: none
2665 =item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
2669 Returns the SQL query and bind vars associated with the invocant.
2671 This is generally used as the RHS for a subquery.
2678 my $attrs = { %{ $self->_resolved_attrs } };
2680 my $aq = $self->result_source->storage->_select_args_to_query (
2681 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
2684 $self->{_attrs}{_sqlmaker_select_args} = $attrs->{_sqlmaker_select_args};
2691 my $attrs = { %{ $self->_resolved_attrs } };
2692 my $storage = $self->result_source->storage;
2693 my (undef, $ident, @args) = $storage->_select_args(
2694 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
2696 $ident = $ident->from if blessed($ident);
2697 $storage->sql_maker->converter->_select_to_dq(
2706 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2708 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2712 my $artist = $schema->resultset('Artist')->find_or_new(
2713 { artist => 'fred' }, { key => 'artists' });
2715 $cd->cd_to_producer->find_or_new({ producer => $producer },
2716 { key => 'primary' });
2718 Find an existing record from this resultset using L</find>. if none exists,
2719 instantiate a new result object and return it. The object will not be saved
2720 into your storage until you call L<DBIx::Class::Row/insert> on it.
2722 You most likely want this method when looking for existing rows using a unique
2723 constraint that is not the primary key, or looking for related rows.
2725 If you want objects to be saved immediately, use L</find_or_create> instead.
2727 B<Note>: Make sure to read the documentation of L</find> and understand the
2728 significance of the C<key> attribute, as its lack may skew your search, and
2729 subsequently result in spurious new objects.
2731 B<Note>: Take care when using C<find_or_new> with a table having
2732 columns with default values that you intend to be automatically
2733 supplied by the database (e.g. an auto_increment primary key column).
2734 In normal usage, the value of such columns should NOT be included at
2735 all in the call to C<find_or_new>, even when set to C<undef>.
2741 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2742 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2743 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2746 return $self->new_result($hash);
2753 =item Arguments: \%col_data
2755 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2759 Attempt to create a single new row or a row with multiple related rows
2760 in the table represented by the resultset (and related tables). This
2761 will not check for duplicate rows before inserting, use
2762 L</find_or_create> to do that.
2764 To create one row for this resultset, pass a hashref of key/value
2765 pairs representing the columns of the table and the values you wish to
2766 store. If the appropriate relationships are set up, foreign key fields
2767 can also be passed an object representing the foreign row, and the
2768 value will be set to its primary key.
2770 To create related objects, pass a hashref of related-object column values
2771 B<keyed on the relationship name>. If the relationship is of type C<multi>
2772 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2773 The process will correctly identify columns holding foreign keys, and will
2774 transparently populate them from the keys of the corresponding relation.
2775 This can be applied recursively, and will work correctly for a structure
2776 with an arbitrary depth and width, as long as the relationships actually
2777 exists and the correct column data has been supplied.
2779 Instead of hashrefs of plain related data (key/value pairs), you may
2780 also pass new or inserted objects. New objects (not inserted yet, see
2781 L</new_result>), will be inserted into their appropriate tables.
2783 Effectively a shortcut for C<< ->new_result(\%col_data)->insert >>.
2785 Example of creating a new row.
2787 $person_rs->create({
2788 name=>"Some Person",
2789 email=>"somebody@someplace.com"
2792 Example of creating a new row and also creating rows in a related C<has_many>
2793 or C<has_one> resultset. Note Arrayref.
2796 { artistid => 4, name => 'Manufactured Crap', cds => [
2797 { title => 'My First CD', year => 2006 },
2798 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2803 Example of creating a new row and also creating a row in a related
2804 C<belongs_to> resultset. Note Hashref.
2807 title=>"Music for Silly Walks",
2810 name=>"Silly Musician",
2818 When subclassing ResultSet never attempt to override this method. Since
2819 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2820 lot of the internals simply never call it, so your override will be
2821 bypassed more often than not. Override either L<DBIx::Class::Row/new>
2822 or L<DBIx::Class::Row/insert> depending on how early in the
2823 L</create> process you need to intervene. See also warning pertaining to
2831 my ($self, $col_data) = @_;
2832 $self->throw_exception( "create needs a hashref" )
2833 unless ref $col_data eq 'HASH';
2834 return $self->new_result($col_data)->insert;
2837 =head2 find_or_create
2841 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2843 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2847 $cd->cd_to_producer->find_or_create({ producer => $producer },
2848 { key => 'primary' });
2850 Tries to find a record based on its primary key or unique constraints; if none
2851 is found, creates one and returns that instead.
2853 my $cd = $schema->resultset('CD')->find_or_create({
2855 artist => 'Massive Attack',
2856 title => 'Mezzanine',
2860 Also takes an optional C<key> attribute, to search by a specific key or unique
2861 constraint. For example:
2863 my $cd = $schema->resultset('CD')->find_or_create(
2865 artist => 'Massive Attack',
2866 title => 'Mezzanine',
2868 { key => 'cd_artist_title' }
2871 B<Note>: Make sure to read the documentation of L</find> and understand the
2872 significance of the C<key> attribute, as its lack may skew your search, and
2873 subsequently result in spurious row creation.
2875 B<Note>: Because find_or_create() reads from the database and then
2876 possibly inserts based on the result, this method is subject to a race
2877 condition. Another process could create a record in the table after
2878 the find has completed and before the create has started. To avoid
2879 this problem, use find_or_create() inside a transaction.
2881 B<Note>: Take care when using C<find_or_create> with a table having
2882 columns with default values that you intend to be automatically
2883 supplied by the database (e.g. an auto_increment primary key column).
2884 In normal usage, the value of such columns should NOT be included at
2885 all in the call to C<find_or_create>, even when set to C<undef>.
2887 See also L</find> and L</update_or_create>. For information on how to declare
2888 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2890 If you need to know if an existing row was found or a new one created use
2891 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2892 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2895 my $cd = $schema->resultset('CD')->find_or_new({
2897 artist => 'Massive Attack',
2898 title => 'Mezzanine',
2902 if( !$cd->in_storage ) {
2909 sub find_or_create {
2911 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2912 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2913 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2916 return $self->create($hash);
2919 =head2 update_or_create
2923 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2925 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2929 $resultset->update_or_create({ col => $val, ... });
2931 Like L</find_or_create>, but if a row is found it is immediately updated via
2932 C<< $found_row->update (\%col_data) >>.
2935 Takes an optional C<key> attribute to search on a specific unique constraint.
2938 # In your application
2939 my $cd = $schema->resultset('CD')->update_or_create(
2941 artist => 'Massive Attack',
2942 title => 'Mezzanine',
2945 { key => 'cd_artist_title' }
2948 $cd->cd_to_producer->update_or_create({
2949 producer => $producer,
2955 B<Note>: Make sure to read the documentation of L</find> and understand the
2956 significance of the C<key> attribute, as its lack may skew your search, and
2957 subsequently result in spurious row creation.
2959 B<Note>: Take care when using C<update_or_create> with a table having
2960 columns with default values that you intend to be automatically
2961 supplied by the database (e.g. an auto_increment primary key column).
2962 In normal usage, the value of such columns should NOT be included at
2963 all in the call to C<update_or_create>, even when set to C<undef>.
2965 See also L</find> and L</find_or_create>. For information on how to declare
2966 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2968 If you need to know if an existing row was updated or a new one created use
2969 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2970 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2975 sub update_or_create {
2977 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2978 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2980 my $row = $self->find($cond, $attrs);
2982 $row->update($cond);
2986 return $self->create($cond);
2989 =head2 update_or_new
2993 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2995 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2999 $resultset->update_or_new({ col => $val, ... });
3001 Like L</find_or_new> but if a row is found it is immediately updated via
3002 C<< $found_row->update (\%col_data) >>.
3006 # In your application
3007 my $cd = $schema->resultset('CD')->update_or_new(
3009 artist => 'Massive Attack',
3010 title => 'Mezzanine',
3013 { key => 'cd_artist_title' }
3016 if ($cd->in_storage) {
3017 # the cd was updated
3020 # the cd is not yet in the database, let's insert it
3024 B<Note>: Make sure to read the documentation of L</find> and understand the
3025 significance of the C<key> attribute, as its lack may skew your search, and
3026 subsequently result in spurious new objects.
3028 B<Note>: Take care when using C<update_or_new> with a table having
3029 columns with default values that you intend to be automatically
3030 supplied by the database (e.g. an auto_increment primary key column).
3031 In normal usage, the value of such columns should NOT be included at
3032 all in the call to C<update_or_new>, even when set to C<undef>.
3034 See also L</find>, L</find_or_create> and L</find_or_new>.
3040 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
3041 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3043 my $row = $self->find( $cond, $attrs );
3044 if ( defined $row ) {
3045 $row->update($cond);
3049 return $self->new_result($cond);
3056 =item Arguments: none
3058 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass> | undef
3062 Gets the contents of the cache for the resultset, if the cache is set.
3064 The cache is populated either by using the L</prefetch> attribute to
3065 L</search> or by calling L</set_cache>.
3077 =item Arguments: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3079 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3083 Sets the contents of the cache for the resultset. Expects an arrayref
3084 of objects of the same class as those produced by the resultset. Note that
3085 if the cache is set, the resultset will return the cached objects rather
3086 than re-querying the database even if the cache attr is not set.
3088 The contents of the cache can also be populated by using the
3089 L</prefetch> attribute to L</search>.
3094 my ( $self, $data ) = @_;
3095 $self->throw_exception("set_cache requires an arrayref")
3096 if defined($data) && (ref $data ne 'ARRAY');
3097 $self->{all_cache} = $data;
3104 =item Arguments: none
3106 =item Return Value: undef
3110 Clears the cache for the resultset.
3115 shift->set_cache(undef);
3122 =item Arguments: none
3124 =item Return Value: true, if the resultset has been paginated
3132 return !!$self->{attrs}{page};
3139 =item Arguments: none
3141 =item Return Value: true, if the resultset has been ordered with C<order_by>.
3149 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
3152 =head2 related_resultset
3156 =item Arguments: $rel_name
3158 =item Return Value: L<$resultset|/search>
3162 Returns a related resultset for the supplied relationship name.
3164 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
3168 sub related_resultset {
3169 my ($self, $rel) = @_;
3171 return $self->{related_resultsets}{$rel}
3172 if defined $self->{related_resultsets}{$rel};
3174 return $self->{related_resultsets}{$rel} = do {
3175 my $rsrc = $self->result_source;
3176 my $rel_info = $rsrc->relationship_info($rel);
3178 $self->throw_exception(
3179 "search_related: result source '" . $rsrc->source_name .
3180 "' has no such relationship $rel")
3183 my $attrs = $self->_chain_relationship($rel);
3185 my $join_count = $attrs->{seen_join}{$rel};
3187 my $alias = $self->result_source->storage
3188 ->relname_to_table_alias($rel, $join_count);
3190 # since this is search_related, and we already slid the select window inwards
3191 # (the select/as attrs were deleted in the beginning), we need to flip all
3192 # left joins to inner, so we get the expected results
3193 # read the comment on top of the actual function to see what this does
3194 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
3197 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3198 delete @{$attrs}{qw(result_class alias)};
3200 my $rel_source = $rsrc->related_source($rel);
3204 # The reason we do this now instead of passing the alias to the
3205 # search_rs below is that if you wrap/overload resultset on the
3206 # source you need to know what alias it's -going- to have for things
3207 # to work sanely (e.g. RestrictWithObject wants to be able to add
3208 # extra query restrictions, and these may need to be $alias.)
3210 my $rel_attrs = $rel_source->resultset_attributes;
3211 local $rel_attrs->{alias} = $alias;
3213 $rel_source->resultset
3217 where => $attrs->{where},
3221 if (my $cache = $self->get_cache) {
3222 my @related_cache = map
3223 { @{$_->related_resultset($rel)->get_cache||[]} }
3227 $new->set_cache(\@related_cache) if @related_cache;
3234 =head2 current_source_alias
3238 =item Arguments: none
3240 =item Return Value: $source_alias
3244 Returns the current table alias for the result source this resultset is built
3245 on, that will be used in the SQL query. Usually it is C<me>.
3247 Currently the source alias that refers to the result set returned by a
3248 L</search>/L</find> family method depends on how you got to the resultset: it's
3249 C<me> by default, but eg. L</search_related> aliases it to the related result
3250 source name (and keeps C<me> referring to the original result set). The long
3251 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3252 (and make this method unnecessary).
3254 Thus it's currently necessary to use this method in predefined queries (see
3255 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3256 source alias of the current result set:
3258 # in a result set class
3260 my ($self, $user) = @_;
3262 my $me = $self->current_source_alias;
3264 return $self->search({
3265 "$me.modified" => $user->id,
3271 sub current_source_alias {
3272 return (shift->{attrs} || {})->{alias} || 'me';
3275 =head2 as_subselect_rs
3279 =item Arguments: none
3281 =item Return Value: L<$resultset|/search>
3285 Act as a barrier to SQL symbols. The resultset provided will be made into a
3286 "virtual view" by including it as a subquery within the from clause. From this
3287 point on, any joined tables are inaccessible to ->search on the resultset (as if
3288 it were simply where-filtered without joins). For example:
3290 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3292 # 'x' now pollutes the query namespace
3294 # So the following works as expected
3295 my $ok_rs = $rs->search({'x.other' => 1});
3297 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3298 # def) we look for one row with contradictory terms and join in another table
3299 # (aliased 'x_2') which we never use
3300 my $broken_rs = $rs->search({'x.name' => 'def'});
3302 my $rs2 = $rs->as_subselect_rs;
3304 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3305 my $not_joined_rs = $rs2->search({'x.other' => 1});
3307 # works as expected: finds a 'table' row related to two x rows (abc and def)
3308 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3310 Another example of when one might use this would be to select a subset of
3311 columns in a group by clause:
3313 my $rs = $schema->resultset('Bar')->search(undef, {
3314 group_by => [qw{ id foo_id baz_id }],
3315 })->as_subselect_rs->search(undef, {
3316 columns => [qw{ id foo_id }]
3319 In the above example normally columns would have to be equal to the group by,
3320 but because we isolated the group by into a subselect the above works.
3324 sub as_subselect_rs {
3327 my $attrs = $self->_resolved_attrs;
3329 my $fresh_rs = (ref $self)->new (
3330 $self->result_source
3333 # these pieces will be locked in the subquery
3334 delete $fresh_rs->{cond};
3335 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3337 return $fresh_rs->search( {}, {
3339 $attrs->{alias} => $self->as_query,
3340 -alias => $attrs->{alias},
3341 -rsrc => $self->result_source,
3343 alias => $attrs->{alias},
3347 # This code is called by search_related, and makes sure there
3348 # is clear separation between the joins before, during, and
3349 # after the relationship. This information is needed later
3350 # in order to properly resolve prefetch aliases (any alias
3351 # with a relation_chain_depth less than the depth of the
3352 # current prefetch is not considered)
3354 # The increments happen twice per join. An even number means a
3355 # relationship specified via a search_related, whereas an odd
3356 # number indicates a join/prefetch added via attributes
3358 # Also this code will wrap the current resultset (the one we
3359 # chain to) in a subselect IFF it contains limiting attributes
3360 sub _chain_relationship {
3361 my ($self, $rel) = @_;
3362 my $source = $self->result_source;
3363 my $attrs = { %{$self->{attrs}||{}} };
3365 # we need to take the prefetch the attrs into account before we
3366 # ->_resolve_join as otherwise they get lost - captainL
3367 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3369 delete @{$attrs}{qw/join prefetch collapse group_by distinct _grouped_by_distinct select as columns +select +as +columns/};
3371 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3374 my @force_subq_attrs = qw/offset rows group_by having/;
3377 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3379 $self->_has_resolved_attr (@force_subq_attrs)
3381 # Nuke the prefetch (if any) before the new $rs attrs
3382 # are resolved (prefetch is useless - we are wrapping
3383 # a subquery anyway).
3384 my $rs_copy = $self->search;
3385 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3386 $rs_copy->{attrs}{join},
3387 delete $rs_copy->{attrs}{prefetch},
3392 -alias => $attrs->{alias},
3393 $attrs->{alias} => $rs_copy->as_query,
3395 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3396 $seen->{-relation_chain_depth} = 0;
3398 elsif ($attrs->{from}) { #shallow copy suffices
3399 $from = [ @{$attrs->{from}} ];
3404 -alias => $attrs->{alias},
3405 $attrs->{alias} => $source->from,
3409 my $jpath = ($seen->{-relation_chain_depth})
3410 ? $from->[-1][0]{-join_path}
3413 my @requested_joins = $source->_resolve_join(
3420 push @$from, @requested_joins;
3422 $seen->{-relation_chain_depth}++;
3424 # if $self already had a join/prefetch specified on it, the requested
3425 # $rel might very well be already included. What we do in this case
3426 # is effectively a no-op (except that we bump up the chain_depth on
3427 # the join in question so we could tell it *is* the search_related)
3430 # we consider the last one thus reverse
3431 for my $j (reverse @requested_joins) {
3432 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3433 if ($rel eq $last_j) {
3434 $j->[0]{-relation_chain_depth}++;
3440 unless ($already_joined) {
3441 push @$from, $source->_resolve_join(
3449 $seen->{-relation_chain_depth}++;
3451 return {%$attrs, from => $from, seen_join => $seen};
3454 sub _resolved_attrs {
3456 return $self->{_attrs} if $self->{_attrs};
3458 my $attrs = { %{ $self->{attrs} || {} } };
3459 my $source = $self->result_source;
3460 my $alias = $attrs->{alias};
3462 $self->throw_exception("Specifying distinct => 1 in conjunction with collapse => 1 is unsupported")
3463 if $attrs->{collapse} and $attrs->{distinct};
3465 # default selection list
3466 $attrs->{columns} = [ $source->columns ]
3467 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3469 # merge selectors together
3470 for (qw/columns select as/) {
3471 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3472 if $attrs->{$_} or $attrs->{"+$_"};
3475 # disassemble columns
3477 if (my $cols = delete $attrs->{columns}) {
3478 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3479 if (ref $c eq 'HASH') {
3480 for my $as (sort keys %$c) {
3481 push @sel, $c->{$as};
3492 # when trying to weed off duplicates later do not go past this point -
3493 # everything added from here on is unbalanced "anyone's guess" stuff
3494 my $dedup_stop_idx = $#as;
3496 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3498 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3499 if $attrs->{select};
3501 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3502 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3504 # disqualify all $alias.col as-bits (inflate-map mandated)
3505 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3507 # de-duplicate the result (remove *identical* select/as pairs)
3508 # and also die on duplicate {as} pointing to different {select}s
3509 # not using a c-style for as the condition is prone to shrinkage
3512 while ($i <= $dedup_stop_idx) {
3513 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3518 elsif ($seen->{$as[$i]}++) {
3519 $self->throw_exception(
3520 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3528 $attrs->{select} = \@sel;
3529 $attrs->{as} = \@as;
3531 $attrs->{from} ||= [{
3533 -alias => $self->{attrs}{alias},
3534 $self->{attrs}{alias} => $source->from,
3537 if ( $attrs->{join} || $attrs->{prefetch} ) {
3539 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3540 if ref $attrs->{from} ne 'ARRAY';
3542 my $join = (delete $attrs->{join}) || {};
3544 if ( defined $attrs->{prefetch} ) {
3545 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3548 $attrs->{from} = # have to copy here to avoid corrupting the original
3550 @{ $attrs->{from} },
3551 $source->_resolve_join(
3554 { %{ $attrs->{seen_join} || {} } },
3555 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3556 ? $attrs->{from}[-1][0]{-join_path}
3563 if ( defined $attrs->{order_by} ) {
3564 $attrs->{order_by} = (
3565 ref( $attrs->{order_by} ) eq 'ARRAY'
3566 ? [ @{ $attrs->{order_by} } ]
3567 : [ $attrs->{order_by} || () ]
3571 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3572 $attrs->{group_by} = [ $attrs->{group_by} ];
3576 # generate selections based on the prefetch helper
3577 my ($prefetch, @prefetch_select, @prefetch_as);
3578 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3579 if defined $attrs->{prefetch};
3583 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3584 if $attrs->{_dark_selector};
3586 $self->throw_exception("Specifying prefetch in conjunction with an explicit collapse => 0 is unsupported")
3587 if defined $attrs->{collapse} and ! $attrs->{collapse};
3589 $attrs->{collapse} = 1;
3591 # this is a separate structure (we don't look in {from} directly)
3592 # as the resolver needs to shift things off the lists to work
3593 # properly (identical-prefetches on different branches)
3595 if (ref $attrs->{from} eq 'ARRAY') {
3597 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3599 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3600 next unless $j->[0]{-alias};
3601 next unless $j->[0]{-join_path};
3602 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3604 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3607 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3608 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3612 my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map );
3614 # save these for after distinct resolution
3615 @prefetch_select = map { $_->[0] } @prefetch;
3616 @prefetch_as = map { $_->[1] } @prefetch;
3619 # run through the resulting joinstructure (starting from our current slot)
3620 # and unset collapse if proven unnecessary
3622 # also while we are at it find out if the current root source has
3623 # been premultiplied by previous related_source chaining
3625 # this allows to predict whether a root object with all other relation
3626 # data set to NULL is in fact unique
3627 if ($attrs->{collapse}) {
3629 if (ref $attrs->{from} eq 'ARRAY') {
3631 if (@{$attrs->{from}} == 1) {
3632 # no joins - no collapse
3633 $attrs->{collapse} = 0;
3636 # find where our table-spec starts
3637 my @fromlist = @{$attrs->{from}};
3639 my $t = shift @fromlist;
3642 # me vs join from-spec distinction - a ref means non-root
3643 if (ref $t eq 'ARRAY') {
3645 $is_multi ||= ! $t->{-is_single};
3647 last if ($t->{-alias} && $t->{-alias} eq $alias);
3648 $attrs->{_main_source_premultiplied} ||= $is_multi;
3651 # no non-singles remaining, nor any premultiplication - nothing to collapse
3653 ! $attrs->{_main_source_premultiplied}
3655 ! List::Util::first { ! $_->[0]{-is_single} } @fromlist
3657 $attrs->{collapse} = 0;
3663 # if we can not analyze the from - err on the side of safety
3664 $attrs->{_main_source_premultiplied} = 1;
3668 # generate the distinct induced group_by before injecting the prefetched select/as parts
3669 if (delete $attrs->{distinct}) {
3670 if ($attrs->{group_by}) {
3671 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3674 $attrs->{_grouped_by_distinct} = 1;
3675 # distinct affects only the main selection part, not what prefetch may add below
3676 ($attrs->{group_by}, my $new_order) = $source->storage->_group_over_selection($attrs);
3678 # FIXME possibly ignore a rewritten order_by (may turn out to be an issue)
3679 # The thinking is: if we are collapsing the subquerying prefetch engine will
3680 # rip stuff apart for us anyway, and we do not want to have a potentially
3681 # function-converted external order_by
3682 # ( there is an explicit if ( collapse && _grouped_by_distinct ) check in DBIHacks )
3683 $attrs->{order_by} = $new_order unless $attrs->{collapse};
3687 # inject prefetch-bound selection (if any)
3688 push @{$attrs->{select}}, @prefetch_select;
3689 push @{$attrs->{as}}, @prefetch_as;
3691 # whether we can get away with the dumbest (possibly DBI-internal) collapser
3692 if ( List::Util::first { $_ =~ /\./ } @{$attrs->{as}} ) {
3693 $attrs->{_related_results_construction} = 1;
3696 # if both page and offset are specified, produce a combined offset
3697 # even though it doesn't make much sense, this is what pre 081xx has
3699 if (my $page = delete $attrs->{page}) {
3701 ($attrs->{rows} * ($page - 1))
3703 ($attrs->{offset} || 0)
3707 return $self->{_attrs} = $attrs;
3711 my ($self, $attr) = @_;
3713 if (ref $attr eq 'HASH') {
3714 return $self->_rollout_hash($attr);
3715 } elsif (ref $attr eq 'ARRAY') {
3716 return $self->_rollout_array($attr);
3722 sub _rollout_array {
3723 my ($self, $attr) = @_;
3726 foreach my $element (@{$attr}) {
3727 if (ref $element eq 'HASH') {
3728 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3729 } elsif (ref $element eq 'ARRAY') {
3730 # XXX - should probably recurse here
3731 push( @rolled_array, @{$self->_rollout_array($element)} );
3733 push( @rolled_array, $element );
3736 return \@rolled_array;
3740 my ($self, $attr) = @_;
3743 foreach my $key (keys %{$attr}) {
3744 push( @rolled_array, { $key => $attr->{$key} } );
3746 return \@rolled_array;
3749 sub _calculate_score {
3750 my ($self, $a, $b) = @_;
3752 if (defined $a xor defined $b) {
3755 elsif (not defined $a) {
3759 if (ref $b eq 'HASH') {
3760 my ($b_key) = keys %{$b};
3761 if (ref $a eq 'HASH') {
3762 my ($a_key) = keys %{$a};
3763 if ($a_key eq $b_key) {
3764 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3769 return ($a eq $b_key) ? 1 : 0;
3772 if (ref $a eq 'HASH') {
3773 my ($a_key) = keys %{$a};
3774 return ($b eq $a_key) ? 1 : 0;
3776 return ($b eq $a) ? 1 : 0;
3781 sub _merge_joinpref_attr {
3782 my ($self, $orig, $import) = @_;
3784 return $import unless defined($orig);
3785 return $orig unless defined($import);
3787 $orig = $self->_rollout_attr($orig);
3788 $import = $self->_rollout_attr($import);
3791 foreach my $import_element ( @{$import} ) {
3792 # find best candidate from $orig to merge $b_element into
3793 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3794 foreach my $orig_element ( @{$orig} ) {
3795 my $score = $self->_calculate_score( $orig_element, $import_element );
3796 if ($score > $best_candidate->{score}) {
3797 $best_candidate->{position} = $position;
3798 $best_candidate->{score} = $score;
3802 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3803 $import_key = '' if not defined $import_key;
3805 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3806 push( @{$orig}, $import_element );
3808 my $orig_best = $orig->[$best_candidate->{position}];
3809 # merge orig_best and b_element together and replace original with merged
3810 if (ref $orig_best ne 'HASH') {
3811 $orig->[$best_candidate->{position}] = $import_element;
3812 } elsif (ref $import_element eq 'HASH') {
3813 my ($key) = keys %{$orig_best};
3814 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3817 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3820 return @$orig ? $orig : ();
3828 require Hash::Merge;
3829 my $hm = Hash::Merge->new;
3831 $hm->specify_behavior({
3834 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3836 if ($defl xor $defr) {
3837 return [ $defl ? $_[0] : $_[1] ];
3842 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3846 return [$_[0], $_[1]];
3850 return $_[1] if !defined $_[0];
3851 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3852 return [$_[0], @{$_[1]}]
3855 return [] if !defined $_[0] and !keys %{$_[1]};
3856 return [ $_[1] ] if !defined $_[0];
3857 return [ $_[0] ] if !keys %{$_[1]};
3858 return [$_[0], $_[1]]
3863 return $_[0] if !defined $_[1];
3864 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3865 return [@{$_[0]}, $_[1]]
3868 my @ret = @{$_[0]} or return $_[1];
3869 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3870 my %idx = map { $_ => 1 } @ret;
3871 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3875 return [ $_[1] ] if ! @{$_[0]};
3876 return $_[0] if !keys %{$_[1]};
3877 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3878 return [ @{$_[0]}, $_[1] ];
3883 return [] if !keys %{$_[0]} and !defined $_[1];
3884 return [ $_[0] ] if !defined $_[1];
3885 return [ $_[1] ] if !keys %{$_[0]};
3886 return [$_[0], $_[1]]
3889 return [] if !keys %{$_[0]} and !@{$_[1]};
3890 return [ $_[0] ] if !@{$_[1]};
3891 return $_[1] if !keys %{$_[0]};
3892 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3893 return [ $_[0], @{$_[1]} ];
3896 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3897 return [ $_[0] ] if !keys %{$_[1]};
3898 return [ $_[1] ] if !keys %{$_[0]};
3899 return [ $_[0] ] if $_[0] eq $_[1];
3900 return [ $_[0], $_[1] ];
3903 } => 'DBIC_RS_ATTR_MERGER');
3907 return $hm->merge ($_[1], $_[2]);
3911 sub STORABLE_freeze {
3912 my ($self, $cloning) = @_;
3913 my $to_serialize = { %$self };
3915 # A cursor in progress can't be serialized (and would make little sense anyway)
3916 # the parser can be regenerated (and can't be serialized)
3917 delete @{$to_serialize}{qw/cursor _row_parser _result_inflator/};
3919 # nor is it sensical to store a not-yet-fired-count pager
3920 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3921 delete $to_serialize->{pager};
3924 Storable::nfreeze($to_serialize);
3927 # need this hook for symmetry
3929 my ($self, $cloning, $serialized) = @_;
3931 %$self = %{ Storable::thaw($serialized) };
3937 =head2 throw_exception
3939 See L<DBIx::Class::Schema/throw_exception> for details.
3943 sub throw_exception {
3946 if (ref $self and my $rsrc = $self->result_source) {
3947 $rsrc->throw_exception(@_)
3950 DBIx::Class::Exception->throw(@_);
3958 # XXX: FIXME: Attributes docs need clearing up
3962 Attributes are used to refine a ResultSet in various ways when
3963 searching for data. They can be passed to any method which takes an
3964 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3967 Default attributes can be set on the result class using
3968 L<DBIx::Class::ResultSource/resultset_attributes>. (Please read
3969 the CAVEATS on that feature before using it!)
3971 These are in no particular order:
3977 =item Value: ( $order_by | \@order_by | \%order_by )
3981 Which column(s) to order the results by.
3983 [The full list of suitable values is documented in
3984 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3987 If a single column name, or an arrayref of names is supplied, the
3988 argument is passed through directly to SQL. The hashref syntax allows
3989 for connection-agnostic specification of ordering direction:
3991 For descending order:
3993 order_by => { -desc => [qw/col1 col2 col3/] }
3995 For explicit ascending order:
3997 order_by => { -asc => 'col' }
3999 The old scalarref syntax (i.e. order_by => \'year DESC') is still
4000 supported, although you are strongly encouraged to use the hashref
4001 syntax as outlined above.
4007 =item Value: \@columns | \%columns | $column
4011 Shortcut to request a particular set of columns to be retrieved. Each
4012 column spec may be a string (a table column name), or a hash (in which
4013 case the key is the C<as> value, and the value is used as the C<select>
4014 expression). Adds C<me.> onto the start of any column without a C<.> in
4015 it and sets C<select> from that, then auto-populates C<as> from
4016 C<select> as normal. (You may also use the C<cols> attribute, as in
4017 earlier versions of DBIC, but this is deprecated.)
4019 Essentially C<columns> does the same as L</select> and L</as>.
4021 columns => [ 'foo', { bar => 'baz' } ]
4025 select => [qw/foo baz/],
4032 =item Value: \@columns
4036 Indicates additional columns to be selected from storage. Works the same as
4037 L</columns> but adds columns to the selection. (You may also use the
4038 C<include_columns> attribute, as in earlier versions of DBIC, but this is
4039 deprecated). For example:-
4041 $schema->resultset('CD')->search(undef, {
4042 '+columns' => ['artist.name'],
4046 would return all CDs and include a 'name' column to the information
4047 passed to object inflation. Note that the 'artist' is the name of the
4048 column (or relationship) accessor, and 'name' is the name of the column
4049 accessor in the related table.
4051 B<NOTE:> You need to explicitly quote '+columns' when defining the attribute.
4052 Not doing so causes Perl to incorrectly interpret +columns as a bareword with a
4053 unary plus operator before it.
4055 =head2 include_columns
4059 =item Value: \@columns
4063 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
4069 =item Value: \@select_columns
4073 Indicates which columns should be selected from the storage. You can use
4074 column names, or in the case of RDBMS back ends, function or stored procedure
4077 $rs = $schema->resultset('Employee')->search(undef, {
4080 { count => 'employeeid' },
4081 { max => { length => 'name' }, -as => 'longest_name' }
4086 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
4088 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
4089 use L</select>, to instruct DBIx::Class how to store the result of the column.
4090 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
4091 identifier aliasing. You can however alias a function, so you can use it in
4092 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
4093 attribute> supplied as shown in the example above.
4095 B<NOTE:> You need to explicitly quote '+select'/'+as' when defining the attributes.
4096 Not doing so causes Perl to incorrectly interpret them as a bareword with a
4097 unary plus operator before it.
4103 Indicates additional columns to be selected from storage. Works the same as
4104 L</select> but adds columns to the default selection, instead of specifying
4113 =item Value: \@inflation_names
4117 Indicates column names for object inflation. That is L</as> indicates the
4118 slot name in which the column value will be stored within the
4119 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
4120 identifier by the C<get_column> method (or via the object accessor B<if one
4121 with the same name already exists>) as shown below. The L</as> attribute has
4122 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
4124 $rs = $schema->resultset('Employee')->search(undef, {
4127 { count => 'employeeid' },
4128 { max => { length => 'name' }, -as => 'longest_name' }
4137 If the object against which the search is performed already has an accessor
4138 matching a column name specified in C<as>, the value can be retrieved using
4139 the accessor as normal:
4141 my $name = $employee->name();
4143 If on the other hand an accessor does not exist in the object, you need to
4144 use C<get_column> instead:
4146 my $employee_count = $employee->get_column('employee_count');
4148 You can create your own accessors if required - see
4149 L<DBIx::Class::Manual::Cookbook> for details.
4155 Indicates additional column names for those added via L</+select>. See L</as>.
4163 =item Value: ($rel_name | \@rel_names | \%rel_names)
4167 Contains a list of relationships that should be joined for this query. For
4170 # Get CDs by Nine Inch Nails
4171 my $rs = $schema->resultset('CD')->search(
4172 { 'artist.name' => 'Nine Inch Nails' },
4173 { join => 'artist' }
4176 Can also contain a hash reference to refer to the other relation's relations.
4179 package MyApp::Schema::Track;
4180 use base qw/DBIx::Class/;
4181 __PACKAGE__->table('track');
4182 __PACKAGE__->add_columns(qw/trackid cd position title/);
4183 __PACKAGE__->set_primary_key('trackid');
4184 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
4187 # In your application
4188 my $rs = $schema->resultset('Artist')->search(
4189 { 'track.title' => 'Teardrop' },
4191 join => { cd => 'track' },
4192 order_by => 'artist.name',
4196 You need to use the relationship (not the table) name in conditions,
4197 because they are aliased as such. The current table is aliased as "me", so
4198 you need to use me.column_name in order to avoid ambiguity. For example:
4200 # Get CDs from 1984 with a 'Foo' track
4201 my $rs = $schema->resultset('CD')->search(
4204 'tracks.name' => 'Foo'
4206 { join => 'tracks' }
4209 If the same join is supplied twice, it will be aliased to <rel>_2 (and
4210 similarly for a third time). For e.g.
4212 my $rs = $schema->resultset('Artist')->search({
4213 'cds.title' => 'Down to Earth',
4214 'cds_2.title' => 'Popular',
4216 join => [ qw/cds cds/ ],
4219 will return a set of all artists that have both a cd with title 'Down
4220 to Earth' and a cd with title 'Popular'.
4222 If you want to fetch related objects from other tables as well, see L</prefetch>
4225 NOTE: An internal join-chain pruner will discard certain joins while
4226 constructing the actual SQL query, as long as the joins in question do not
4227 affect the retrieved result. This for example includes 1:1 left joins
4228 that are not part of the restriction specification (WHERE/HAVING) nor are
4229 a part of the query selection.
4231 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4237 =item Value: (0 | 1)
4241 When set to a true value, indicates that any rows fetched from joined has_many
4242 relationships are to be aggregated into the corresponding "parent" object. For
4243 example, the resultset:
4245 my $rs = $schema->resultset('CD')->search({}, {
4246 '+columns' => [ qw/ tracks.title tracks.position / ],
4251 While executing the following query:
4253 SELECT me.*, tracks.title, tracks.position
4255 LEFT JOIN track tracks
4256 ON tracks.cdid = me.cdid
4258 Will return only as many objects as there are rows in the CD source, even
4259 though the result of the query may span many rows. Each of these CD objects
4260 will in turn have multiple "Track" objects hidden behind the has_many
4261 generated accessor C<tracks>. Without C<< collapse => 1 >>, the return values
4262 of this resultset would be as many CD objects as there are tracks (a "Cartesian
4263 product"), with each CD object containing exactly one of all fetched Track data.
4265 When a collapse is requested on a non-ordered resultset, an order by some
4266 unique part of the main source (the left-most table) is inserted automatically.
4267 This is done so that the resultset is allowed to be "lazy" - calling
4268 L<< $rs->next|/next >> will fetch only as many rows as it needs to build the next
4269 object with all of its related data.
4271 If an L</order_by> is already declared, and orders the resultset in a way that
4272 makes collapsing as described above impossible (e.g. C<< ORDER BY
4273 has_many_rel.column >> or C<ORDER BY RANDOM()>), DBIC will automatically
4274 switch to "eager" mode and slurp the entire resultset before constructing the
4275 first object returned by L</next>.
4277 Setting this attribute on a resultset that does not join any has_many
4278 relations is a no-op.
4280 For a more in-depth discussion, see L</PREFETCHING>.
4286 =item Value: ($rel_name | \@rel_names | \%rel_names)
4290 This attribute is a shorthand for specifying a L</join> spec, adding all
4291 columns from the joined related sources as L</+columns> and setting
4292 L</collapse> to a true value. For example, the following two queries are
4295 my $rs = $schema->resultset('Artist')->search({}, {
4296 prefetch => { cds => ['genre', 'tracks' ] },
4301 my $rs = $schema->resultset('Artist')->search({}, {
4302 join => { cds => ['genre', 'tracks' ] },
4306 { +{ "cds.$_" => "cds.$_" } }
4307 $schema->source('Artist')->related_source('cds')->columns
4310 { +{ "cds.genre.$_" => "genre.$_" } }
4311 $schema->source('Artist')->related_source('cds')->related_source('genre')->columns
4314 { +{ "cds.tracks.$_" => "tracks.$_" } }
4315 $schema->source('Artist')->related_source('cds')->related_source('tracks')->columns
4320 Both producing the following SQL:
4322 SELECT me.artistid, me.name, me.rank, me.charfield,
4323 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track,
4324 genre.genreid, genre.name,
4325 tracks.trackid, tracks.cd, tracks.position, tracks.title, tracks.last_updated_on, tracks.last_updated_at
4328 ON cds.artist = me.artistid
4329 LEFT JOIN genre genre
4330 ON genre.genreid = cds.genreid
4331 LEFT JOIN track tracks
4332 ON tracks.cd = cds.cdid
4333 ORDER BY me.artistid
4335 While L</prefetch> implies a L</join>, it is ok to mix the two together, as
4336 the arguments are properly merged and generally do the right thing. For
4337 example, you may want to do the following:
4339 my $artists_and_cds_without_genre = $schema->resultset('Artist')->search(
4340 { 'genre.genreid' => undef },
4342 join => { cds => 'genre' },
4347 Which generates the following SQL:
4349 SELECT me.artistid, me.name, me.rank, me.charfield,
4350 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track
4353 ON cds.artist = me.artistid
4354 LEFT JOIN genre genre
4355 ON genre.genreid = cds.genreid
4356 WHERE genre.genreid IS NULL
4357 ORDER BY me.artistid
4359 For a more in-depth discussion, see L</PREFETCHING>.
4365 =item Value: $source_alias
4369 Sets the source alias for the query. Normally, this defaults to C<me>, but
4370 nested search queries (sub-SELECTs) might need specific aliases set to
4371 reference inner queries. For example:
4374 ->related_resultset('CDs')
4375 ->related_resultset('Tracks')
4377 'track.id' => { -ident => 'none_search.id' },
4381 my $ids = $self->search({
4384 alias => 'none_search',
4385 group_by => 'none_search.id',
4386 })->get_column('id')->as_query;
4388 $self->search({ id => { -in => $ids } })
4390 This attribute is directly tied to L</current_source_alias>.
4400 Makes the resultset paged and specifies the page to retrieve. Effectively
4401 identical to creating a non-pages resultset and then calling ->page($page)
4404 If L</rows> attribute is not specified it defaults to 10 rows per page.
4406 When you have a paged resultset, L</count> will only return the number
4407 of rows in the page. To get the total, use the L</pager> and call
4408 C<total_entries> on it.
4418 Specifies the maximum number of rows for direct retrieval or the number of
4419 rows per page if the page attribute or method is used.
4425 =item Value: $offset
4429 Specifies the (zero-based) row number for the first row to be returned, or the
4430 of the first row of the first page if paging is used.
4432 =head2 software_limit
4436 =item Value: (0 | 1)
4440 When combined with L</rows> and/or L</offset> the generated SQL will not
4441 include any limit dialect stanzas. Instead the entire result will be selected
4442 as if no limits were specified, and DBIC will perform the limit locally, by
4443 artificially advancing and finishing the resulting L</cursor>.
4445 This is the recommended way of performing resultset limiting when no sane RDBMS
4446 implementation is available (e.g.
4447 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4448 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4454 =item Value: \@columns
4458 A arrayref of columns to group by. Can include columns of joined tables.
4460 group_by => [qw/ column1 column2 ... /]
4466 =item Value: $condition
4470 HAVING is a select statement attribute that is applied between GROUP BY and
4471 ORDER BY. It is applied to the after the grouping calculations have been
4474 having => { 'count_employee' => { '>=', 100 } }
4476 or with an in-place function in which case literal SQL is required:
4478 having => \[ 'count(employee) >= ?', [ count => 100 ] ]
4484 =item Value: (0 | 1)
4488 Set to 1 to automatically generate a L</group_by> clause based on the selection
4489 (including intelligent handling of L</order_by> contents). Note that the group
4490 criteria calculation takes place over the B<final> selection. This includes
4491 any L</+columns>, L</+select> or L</order_by> additions in subsequent
4492 L</search> calls, and standalone columns selected via
4493 L<DBIx::Class::ResultSetColumn> (L</get_column>). A notable exception are the
4494 extra selections specified via L</prefetch> - such selections are explicitly
4495 excluded from group criteria calculations.
4497 If the final ResultSet also explicitly defines a L</group_by> attribute, this
4498 setting is ignored and an appropriate warning is issued.
4504 Adds to the WHERE clause.
4506 # only return rows WHERE deleted IS NULL for all searches
4507 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4509 Can be overridden by passing C<< { where => undef } >> as an attribute
4512 For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
4518 Set to 1 to cache search results. This prevents extra SQL queries if you
4519 revisit rows in your ResultSet:
4521 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4523 while( my $artist = $resultset->next ) {
4527 $rs->first; # without cache, this would issue a query
4529 By default, searches are not cached.
4531 For more examples of using these attributes, see
4532 L<DBIx::Class::Manual::Cookbook>.
4538 =item Value: ( 'update' | 'shared' | \$scalar )
4542 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4543 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4548 DBIx::Class supports arbitrary related data prefetching from multiple related
4549 sources. Any combination of relationship types and column sets are supported.
4550 If L<collapsing|/collapse> is requested, there is an additional requirement of
4551 selecting enough data to make every individual object uniquely identifiable.
4553 Here are some more involved examples, based on the following relationship map:
4556 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4557 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4558 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4560 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4562 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4566 my $rs = $schema->resultset('Tag')->search(
4575 The initial search results in SQL like the following:
4577 SELECT tag.*, cd.*, artist.* FROM tag
4578 JOIN cd ON tag.cd = cd.cdid
4579 JOIN artist ON cd.artist = artist.artistid
4581 L<DBIx::Class> has no need to go back to the database when we access the
4582 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4585 Simple prefetches will be joined automatically, so there is no need
4586 for a C<join> attribute in the above search.
4588 The L</prefetch> attribute can be used with any of the relationship types
4589 and multiple prefetches can be specified together. Below is a more complex
4590 example that prefetches a CD's artist, its liner notes (if present),
4591 the cover image, the tracks on that CD, and the guests on those
4594 my $rs = $schema->resultset('CD')->search(
4598 { artist => 'record_label'}, # belongs_to => belongs_to
4599 'liner_note', # might_have
4600 'cover_image', # has_one
4601 { tracks => 'guests' }, # has_many => has_many
4606 This will produce SQL like the following:
4608 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4612 ON artist.artistid = me.artistid
4613 JOIN record_label record_label
4614 ON record_label.labelid = artist.labelid
4615 LEFT JOIN track tracks
4616 ON tracks.cdid = me.cdid
4617 LEFT JOIN guest guests
4618 ON guests.trackid = track.trackid
4619 LEFT JOIN liner_notes liner_note
4620 ON liner_note.cdid = me.cdid
4621 JOIN cd_artwork cover_image
4622 ON cover_image.cdid = me.cdid
4625 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4626 C<tracks>, and C<guests> of the CD will all be available through the
4627 relationship accessors without the need for additional queries to the
4632 Prefetch does a lot of deep magic. As such, it may not behave exactly
4633 as you might expect.
4639 Prefetch uses the L</cache> to populate the prefetched relationships. This
4640 may or may not be what you want.
4644 If you specify a condition on a prefetched relationship, ONLY those
4645 rows that match the prefetched condition will be fetched into that relationship.
4646 This means that adding prefetch to a search() B<may alter> what is returned by
4647 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4649 my $artist_rs = $schema->resultset('Artist')->search({
4655 my $count = $artist_rs->first->cds->count;
4657 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4659 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4661 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4663 That cmp_ok() may or may not pass depending on the datasets involved. In other
4664 words the C<WHERE> condition would apply to the entire dataset, just like
4665 it would in regular SQL. If you want to add a condition only to the "right side"
4666 of a C<LEFT JOIN> - consider declaring and using a L<relationship with a custom
4667 condition|DBIx::Class::Relationship::Base/condition>
4671 =head1 DBIC BIND VALUES
4673 Because DBIC may need more information to bind values than just the column name
4674 and value itself, it uses a special format for both passing and receiving bind
4675 values. Each bind value should be composed of an arrayref of
4676 C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
4682 If present (in any form), this is what is being passed directly to bind_param.
4683 Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
4684 a single numerical type, while DBD::Pg takes a hashref if bind options.)
4686 If this is specified, all other bind options described below are ignored.
4690 If present, this is used to infer the actual bind attribute by passing to
4691 C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
4692 "data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
4694 Note that the data type is somewhat freeform (hence the sqlt_ prefix);
4695 currently drivers are expected to "Do the Right Thing" when given a common
4696 datatype name. (Not ideal, but that's what we got at this point.)
4700 Currently used to correctly allocate buffers for bind_param_inout().
4701 Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
4702 or to a sensible value based on the "data_type".
4706 Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
4707 explicitly specified they are never overridden). Also used by some weird DBDs,
4708 where the column name should be available at bind_param time (e.g. Oracle).
4712 For backwards compatibility and convenience, the following shortcuts are
4715 [ $name => $val ] === [ { dbic_colname => $name }, $val ]
4716 [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
4717 [ undef, $val ] === [ {}, $val ]
4718 $val === [ {}, $val ]
4720 =head1 AUTHOR AND CONTRIBUTORS
4722 See L<AUTHOR|DBIx::Class/AUTHOR> and L<CONTRIBUTORS|DBIx::Class/CONTRIBUTORS> in DBIx::Class
4726 You may distribute this code under the same terms as Perl itself.