1 package DBIx::Class::ResultSet;
5 use base qw/DBIx::Class/;
7 use DBIx::Class::Exception;
8 use DBIx::Class::ResultSetColumn;
9 use Scalar::Util qw/blessed weaken/;
11 use Data::Compare (); # no imports!!! guard against insane architecture
13 # not importing first() as it will clash with our own method
17 # De-duplication in _merge_attr() is disabled, but left in for reference
18 # (the merger is used for other things that ought not to be de-duped)
19 *__HM_DEDUP = sub () { 0 };
29 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class result_source/);
33 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
37 my $users_rs = $schema->resultset('User');
38 while( $user = $users_rs->next) {
39 print $user->username;
42 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
43 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
47 A ResultSet is an object which stores a set of conditions representing
48 a query. It is the backbone of DBIx::Class (i.e. the really
49 important/useful bit).
51 No SQL is executed on the database when a ResultSet is created, it
52 just stores all the conditions needed to create the query.
54 A basic ResultSet representing the data of an entire table is returned
55 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
56 L<Source|DBIx::Class::Manual::Glossary/Source> name.
58 my $users_rs = $schema->resultset('User');
60 A new ResultSet is returned from calling L</search> on an existing
61 ResultSet. The new one will contain all the conditions of the
62 original, plus any new conditions added in the C<search> call.
64 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
65 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
68 The query that the ResultSet represents is B<only> executed against
69 the database when these methods are called:
70 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
72 If a resultset is used in a numeric context it returns the L</count>.
73 However, if it is used in a boolean context it is B<always> true. So if
74 you want to check if a resultset has any results, you must use C<if $rs
77 =head1 CUSTOM ResultSet CLASSES THAT USE Moose
79 If you want to make your custom ResultSet classes with L<Moose>, use a template
82 package MyApp::Schema::ResultSet::User;
85 use namespace::autoclean;
87 extends 'DBIx::Class::ResultSet';
89 sub BUILDARGS { $_[2] }
93 __PACKAGE__->meta->make_immutable;
97 The L<MooseX::NonMoose> is necessary so that the L<Moose> constructor does not
98 clash with the regular ResultSet constructor. Alternatively, you can use:
100 __PACKAGE__->meta->make_immutable(inline_constructor => 0);
102 The L<BUILDARGS|Moose::Manual::Construction/BUILDARGS> is necessary because the
103 signature of the ResultSet C<new> is C<< ->new($source, \%args) >>.
107 =head2 Chaining resultsets
109 Let's say you've got a query that needs to be run to return some data
110 to the user. But, you have an authorization system in place that
111 prevents certain users from seeing certain information. So, you want
112 to construct the basic query in one method, but add constraints to it in
117 my $request = $self->get_request; # Get a request object somehow.
118 my $schema = $self->result_source->schema;
120 my $cd_rs = $schema->resultset('CD')->search({
121 title => $request->param('title'),
122 year => $request->param('year'),
125 $cd_rs = $self->apply_security_policy( $cd_rs );
127 return $cd_rs->all();
130 sub apply_security_policy {
139 =head3 Resolving conditions and attributes
141 When a resultset is chained from another resultset, conditions and
142 attributes with the same keys need resolving.
144 L</join>, L</prefetch>, L</+select>, L</+as> attributes are merged
145 into the existing ones from the original resultset.
147 The L</where> and L</having> attributes, and any search conditions, are
148 merged with an SQL C<AND> to the existing condition from the original
151 All other attributes are overridden by any new ones supplied in the
154 =head2 Multiple queries
156 Since a resultset just defines a query, you can do all sorts of
157 things with it with the same object.
159 # Don't hit the DB yet.
160 my $cd_rs = $schema->resultset('CD')->search({
161 title => 'something',
165 # Each of these hits the DB individually.
166 my $count = $cd_rs->count;
167 my $most_recent = $cd_rs->get_column('date_released')->max();
168 my @records = $cd_rs->all;
170 And it's not just limited to SELECT statements.
176 $cd_rs->create({ artist => 'Fred' });
178 Which is the same as:
180 $schema->resultset('CD')->create({
181 title => 'something',
186 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
194 =item Arguments: $source, \%$attrs
196 =item Return Value: $rs
200 The resultset constructor. Takes a source object (usually a
201 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
202 L</ATTRIBUTES> below). Does not perform any queries -- these are
203 executed as needed by the other methods.
205 Generally you won't need to construct a resultset manually. You'll
206 automatically get one from e.g. a L</search> called in scalar context:
208 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
210 IMPORTANT: If called on an object, proxies to new_result instead so
212 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
214 will return a CD object, not a ResultSet.
220 return $class->new_result(@_) if ref $class;
222 my ($source, $attrs) = @_;
223 $source = $source->resolve
224 if $source->isa('DBIx::Class::ResultSourceHandle');
225 $attrs = { %{$attrs||{}} };
227 if ($attrs->{page}) {
228 $attrs->{rows} ||= 10;
231 $attrs->{alias} ||= 'me';
234 result_source => $source,
235 cond => $attrs->{where},
240 # if there is a dark selector, this means we are already in a
241 # chain and the cleanup/sanification was taken care of by
243 $self->_normalize_selection($attrs)
244 unless $attrs->{_dark_selector};
247 $attrs->{result_class} || $source->result_class
257 =item Arguments: $cond, \%attrs?
259 =item Return Value: $resultset (scalar context) || @row_objs (list context)
263 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
264 my $new_rs = $cd_rs->search({ year => 2005 });
266 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
267 # year = 2005 OR year = 2004
269 In list context, C<< ->all() >> is called implicitly on the resultset, thus
270 returning a list of row objects instead. To avoid that, use L</search_rs>.
272 If you need to pass in additional attributes but no additional condition,
273 call it as C<search(undef, \%attrs)>.
275 # "SELECT name, artistid FROM $artist_table"
276 my @all_artists = $schema->resultset('Artist')->search(undef, {
277 columns => [qw/name artistid/],
280 For a list of attributes that can be passed to C<search>, see
281 L</ATTRIBUTES>. For more examples of using this function, see
282 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
283 documentation for the first argument, see L<SQL::Abstract>
284 and its extension L<DBIx::Class::SQLMaker>.
286 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
290 Note that L</search> does not process/deflate any of the values passed in the
291 L<SQL::Abstract>-compatible search condition structure. This is unlike other
292 condition-bound methods L</new>, L</create> and L</find>. The user must ensure
293 manually that any value passed to this method will stringify to something the
294 RDBMS knows how to deal with. A notable example is the handling of L<DateTime>
295 objects, for more info see:
296 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
302 my $rs = $self->search_rs( @_ );
307 elsif (defined wantarray) {
311 # we can be called by a relationship helper, which in
312 # turn may be called in void context due to some braindead
313 # overload or whatever else the user decided to be clever
314 # at this particular day. Thus limit the exception to
315 # external code calls only
316 $self->throw_exception ('->search is *not* a mutator, calling it in void context makes no sense')
317 if (caller)[0] !~ /^\QDBIx::Class::/;
327 =item Arguments: $cond, \%attrs?
329 =item Return Value: $resultset
333 This method does the same exact thing as search() except it will
334 always return a resultset, even in list context.
341 # Special-case handling for (undef, undef).
342 if ( @_ == 2 && !defined $_[1] && !defined $_[0] ) {
348 if (ref $_[-1] eq 'HASH') {
349 # copy for _normalize_selection
350 $call_attrs = { %{ pop @_ } };
352 elsif (! defined $_[-1] ) {
353 pop @_; # search({}, undef)
357 # see if we can keep the cache (no $rs changes)
359 my %safe = (alias => 1, cache => 1);
360 if ( ! List::Util::first { !$safe{$_} } keys %$call_attrs and (
363 ref $_[0] eq 'HASH' && ! keys %{$_[0]}
365 ref $_[0] eq 'ARRAY' && ! @{$_[0]}
367 $cache = $self->get_cache;
370 my $rsrc = $self->result_source;
372 my $old_attrs = { %{$self->{attrs}} };
373 my $old_having = delete $old_attrs->{having};
374 my $old_where = delete $old_attrs->{where};
376 my $new_attrs = { %$old_attrs };
378 # take care of call attrs (only if anything is changing)
379 if (keys %$call_attrs) {
381 my @selector_attrs = qw/select as columns cols +select +as +columns include_columns/;
383 # reset the current selector list if new selectors are supplied
384 if (List::Util::first { exists $call_attrs->{$_} } qw/columns cols select as/) {
385 delete @{$old_attrs}{(@selector_attrs, '_dark_selector')};
388 # Normalize the new selector list (operates on the passed-in attr structure)
389 # Need to do it on every chain instead of only once on _resolved_attrs, in
390 # order to allow detection of empty vs partial 'as'
391 $call_attrs->{_dark_selector} = $old_attrs->{_dark_selector}
392 if $old_attrs->{_dark_selector};
393 $self->_normalize_selection ($call_attrs);
395 # start with blind overwriting merge, exclude selector attrs
396 $new_attrs = { %{$old_attrs}, %{$call_attrs} };
397 delete @{$new_attrs}{@selector_attrs};
399 for (@selector_attrs) {
400 $new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
401 if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
404 # older deprecated name, use only if {columns} is not there
405 if (my $c = delete $new_attrs->{cols}) {
406 if ($new_attrs->{columns}) {
407 carp "Resultset specifies both the 'columns' and the legacy 'cols' attributes - ignoring 'cols'";
410 $new_attrs->{columns} = $c;
415 # join/prefetch use their own crazy merging heuristics
416 foreach my $key (qw/join prefetch/) {
417 $new_attrs->{$key} = $self->_merge_joinpref_attr($old_attrs->{$key}, $call_attrs->{$key})
418 if exists $call_attrs->{$key};
421 # stack binds together
422 $new_attrs->{bind} = [ @{ $old_attrs->{bind} || [] }, @{ $call_attrs->{bind} || [] } ];
426 # rip apart the rest of @_, parse a condition
429 if (ref $_[0] eq 'HASH') {
430 (keys %{$_[0]}) ? $_[0] : undef
436 $self->throw_exception('Odd number of arguments to search')
444 if( @_ > 1 and ! $rsrc->result_class->isa('DBIx::Class::CDBICompat') ) {
445 carp_unique 'search( %condition ) is deprecated, use search( \%condition ) instead';
448 for ($old_where, $call_cond) {
450 $new_attrs->{where} = $self->_stack_cond (
451 $_, $new_attrs->{where}
456 if (defined $old_having) {
457 $new_attrs->{having} = $self->_stack_cond (
458 $old_having, $new_attrs->{having}
462 my $rs = (ref $self)->new($rsrc, $new_attrs);
464 $rs->set_cache($cache) if ($cache);
470 sub _normalize_selection {
471 my ($self, $attrs) = @_;
474 $attrs->{'+columns'} = $self->_merge_attr($attrs->{'+columns'}, delete $attrs->{include_columns})
475 if exists $attrs->{include_columns};
477 # columns are always placed first, however
479 # Keep the X vs +X separation until _resolved_attrs time - this allows to
480 # delay the decision on whether to use a default select list ($rsrc->columns)
481 # allowing stuff like the remove_columns helper to work
483 # select/as +select/+as pairs need special handling - the amount of select/as
484 # elements in each pair does *not* have to be equal (think multicolumn
485 # selectors like distinct(foo, bar) ). If the selector is bare (no 'as'
486 # supplied at all) - try to infer the alias, either from the -as parameter
487 # of the selector spec, or use the parameter whole if it looks like a column
488 # name (ugly legacy heuristic). If all fails - leave the selector bare (which
489 # is ok as well), but make sure no more additions to the 'as' chain take place
490 for my $pref ('', '+') {
492 my ($sel, $as) = map {
493 my $key = "${pref}${_}";
495 my $val = [ ref $attrs->{$key} eq 'ARRAY'
497 : $attrs->{$key} || ()
499 delete $attrs->{$key};
503 if (! @$as and ! @$sel ) {
506 elsif (@$as and ! @$sel) {
507 $self->throw_exception(
508 "Unable to handle ${pref}as specification (@$as) without a corresponding ${pref}select"
512 # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
513 # if any @$as has been supplied we assume the user knows what (s)he is doing
514 # and blindly keep stacking up pieces
515 unless ($attrs->{_dark_selector}) {
518 if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
519 push @$as, $_->{-as};
521 # assume any plain no-space, no-parenthesis string to be a column spec
522 # FIXME - this is retarded but is necessary to support shit like 'count(foo)'
523 elsif ( ! ref $_ and $_ =~ /^ [^\s\(\)]+ $/x) {
526 # if all else fails - raise a flag that no more aliasing will be allowed
528 $attrs->{_dark_selector} = {
530 string => ($dark_sel_dumper ||= do {
531 require Data::Dumper::Concise;
532 Data::Dumper::Concise::DumperObject()->Indent(0);
533 })->Values([$_])->Dump
541 elsif (@$as < @$sel) {
542 $self->throw_exception(
543 "Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
546 elsif ($pref and $attrs->{_dark_selector}) {
547 $self->throw_exception(
548 "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
554 $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
555 $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
560 my ($self, $left, $right) = @_;
562 # collapse single element top-level conditions
563 # (single pass only, unlikely to need recursion)
564 for ($left, $right) {
565 if (ref $_ eq 'ARRAY') {
573 elsif (ref $_ eq 'HASH') {
574 my ($first, $more) = keys %$_;
577 if (! defined $first) {
581 elsif (! defined $more) {
582 if ($first eq '-and' and ref $_->{'-and'} eq 'HASH') {
585 elsif ($first eq '-or' and ref $_->{'-or'} eq 'ARRAY') {
592 # merge hashes with weeding out of duplicates (simple cases only)
593 if (ref $left eq 'HASH' and ref $right eq 'HASH') {
595 # shallow copy to destroy
596 $right = { %$right };
597 for (grep { exists $right->{$_} } keys %$left) {
598 # the use of eq_deeply here is justified - the rhs of an
599 # expression can contain a lot of twisted weird stuff
600 delete $right->{$_} if Data::Compare::Compare( $left->{$_}, $right->{$_} );
603 $right = undef unless keys %$right;
607 if (defined $left xor defined $right) {
608 return defined $left ? $left : $right;
610 elsif (! defined $left) {
614 return { -and => [ $left, $right ] };
618 =head2 search_literal
622 =item Arguments: $sql_fragment, @bind_values
624 =item Return Value: $resultset (scalar context) || @row_objs (list context)
628 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
629 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
631 Pass a literal chunk of SQL to be added to the conditional part of the
634 CAVEAT: C<search_literal> is provided for Class::DBI compatibility and should
635 only be used in that context. C<search_literal> is a convenience method.
636 It is equivalent to calling $schema->search(\[]), but if you want to ensure
637 columns are bound correctly, use C<search>.
639 Example of how to use C<search> instead of C<search_literal>
641 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
642 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
645 See L<DBIx::Class::Manual::Cookbook/Searching> and
646 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
647 require C<search_literal>.
652 my ($self, $sql, @bind) = @_;
654 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
657 return $self->search(\[ $sql, map [ __DUMMY__ => $_ ], @bind ], ($attr || () ));
664 =item Arguments: \%columns_values | @pk_values, \%attrs?
666 =item Return Value: $row_object | undef
670 Finds and returns a single row based on supplied criteria. Takes either a
671 hashref with the same format as L</create> (including inference of foreign
672 keys from related objects), or a list of primary key values in the same
673 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
674 declaration on the L</result_source>.
676 In either case an attempt is made to combine conditions already existing on
677 the resultset with the condition passed to this method.
679 To aid with preparing the correct query for the storage you may supply the
680 C<key> attribute, which is the name of a
681 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
682 unique constraint corresponding to the
683 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
684 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
685 to construct a query that satisfies the named unique constraint fully (
686 non-NULL values for each column member of the constraint) an exception is
689 If no C<key> is specified, the search is carried over all unique constraints
690 which are fully defined by the available condition.
692 If no such constraint is found, C<find> currently defaults to a simple
693 C<< search->(\%column_values) >> which may or may not do what you expect.
694 Note that this fallback behavior may be deprecated in further versions. If
695 you need to search with arbitrary conditions - use L</search>. If the query
696 resulting from this fallback produces more than one row, a warning to the
697 effect is issued, though only the first row is constructed and returned as
700 In addition to C<key>, L</find> recognizes and applies standard
701 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
703 Note that if you have extra concerns about the correctness of the resulting
704 query you need to specify the C<key> attribute and supply the entire condition
705 as an argument to find (since it is not always possible to perform the
706 combination of the resultset condition with the supplied one, especially if
707 the resultset condition contains literal sql).
709 For example, to find a row by its primary key:
711 my $cd = $schema->resultset('CD')->find(5);
713 You can also find a row by a specific unique constraint:
715 my $cd = $schema->resultset('CD')->find(
717 artist => 'Massive Attack',
718 title => 'Mezzanine',
720 { key => 'cd_artist_title' }
723 See also L</find_or_create> and L</update_or_create>.
729 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
731 my $rsrc = $self->result_source;
734 if (exists $attrs->{key}) {
735 $constraint_name = defined $attrs->{key}
737 : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
741 # Parse out the condition from input
744 if (ref $_[0] eq 'HASH') {
745 $call_cond = { %{$_[0]} };
748 # if only values are supplied we need to default to 'primary'
749 $constraint_name = 'primary' unless defined $constraint_name;
751 my @c_cols = $rsrc->unique_constraint_columns($constraint_name);
753 $self->throw_exception(
754 "No constraint columns, maybe a malformed '$constraint_name' constraint?"
757 $self->throw_exception (
758 'find() expects either a column/value hashref, or a list of values '
759 . "corresponding to the columns of the specified unique constraint '$constraint_name'"
760 ) unless @c_cols == @_;
763 @{$call_cond}{@c_cols} = @_;
767 for my $key (keys %$call_cond) {
769 my $keyref = ref($call_cond->{$key})
771 my $relinfo = $rsrc->relationship_info($key)
773 my $val = delete $call_cond->{$key};
775 next if $keyref eq 'ARRAY'; # has_many for multi_create
777 my $rel_q = $rsrc->_resolve_condition(
778 $relinfo->{cond}, $val, $key, $key
780 die "Can't handle complex relationship conditions in find" if ref($rel_q) ne 'HASH';
781 @related{keys %$rel_q} = values %$rel_q;
785 # relationship conditions take precedence (?)
786 @{$call_cond}{keys %related} = values %related;
788 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
790 if (defined $constraint_name) {
791 $final_cond = $self->_qualify_cond_columns (
793 $self->_build_unique_cond (
801 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
802 # This means that we got here after a merger of relationship conditions
803 # in ::Relationship::Base::search_related (the row method), and furthermore
804 # the relationship is of the 'single' type. This means that the condition
805 # provided by the relationship (already attached to $self) is sufficient,
806 # as there can be only one row in the database that would satisfy the
810 # no key was specified - fall down to heuristics mode:
811 # run through all unique queries registered on the resultset, and
812 # 'OR' all qualifying queries together
813 my (@unique_queries, %seen_column_combinations);
814 for my $c_name ($rsrc->unique_constraint_names) {
815 next if $seen_column_combinations{
816 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
819 push @unique_queries, try {
820 $self->_build_unique_cond ($c_name, $call_cond, 'croak_on_nulls')
824 $final_cond = @unique_queries
825 ? [ map { $self->_qualify_cond_columns($_, $alias) } @unique_queries ]
826 : $self->_non_unique_find_fallback ($call_cond, $attrs)
830 # Run the query, passing the result_class since it should propagate for find
831 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
832 if (keys %{$rs->_resolved_attrs->{collapse}}) {
834 carp "Query returned more than one row" if $rs->next;
842 # This is a stop-gap method as agreed during the discussion on find() cleanup:
843 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
845 # It is invoked when find() is called in legacy-mode with insufficiently-unique
846 # condition. It is provided for overrides until a saner way forward is devised
848 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
849 # the road. Please adjust your tests accordingly to catch this situation early
850 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
852 # The method will not be removed without an adequately complete replacement
853 # for strict-mode enforcement
854 sub _non_unique_find_fallback {
855 my ($self, $cond, $attrs) = @_;
857 return $self->_qualify_cond_columns(
859 exists $attrs->{alias}
861 : $self->{attrs}{alias}
866 sub _qualify_cond_columns {
867 my ($self, $cond, $alias) = @_;
869 my %aliased = %$cond;
870 for (keys %aliased) {
871 $aliased{"$alias.$_"} = delete $aliased{$_}
878 sub _build_unique_cond {
879 my ($self, $constraint_name, $extra_cond, $croak_on_null) = @_;
881 my @c_cols = $self->result_source->unique_constraint_columns($constraint_name);
883 # combination may fail if $self->{cond} is non-trivial
884 my ($final_cond) = try {
885 $self->_merge_with_rscond ($extra_cond)
890 # trim out everything not in $columns
891 $final_cond = { map {
892 exists $final_cond->{$_}
893 ? ( $_ => $final_cond->{$_} )
897 if (my @missing = grep
898 { ! ($croak_on_null ? defined $final_cond->{$_} : exists $final_cond->{$_}) }
901 $self->throw_exception( sprintf ( "Unable to satisfy requested constraint '%s', no values for column(s): %s",
903 join (', ', map { "'$_'" } @missing),
910 !$ENV{DBIC_NULLABLE_KEY_NOWARN}
912 my @undefs = grep { ! defined $final_cond->{$_} } (keys %$final_cond)
914 carp_unique ( sprintf (
915 "NULL/undef values supplied for requested unique constraint '%s' (NULL "
916 . 'values in column(s): %s). This is almost certainly not what you wanted, '
917 . 'though you can set DBIC_NULLABLE_KEY_NOWARN to disable this warning.',
919 join (', ', map { "'$_'" } @undefs),
926 =head2 search_related
930 =item Arguments: $rel, $cond, \%attrs?
932 =item Return Value: $new_resultset (scalar context) || @row_objs (list context)
936 $new_rs = $cd_rs->search_related('artist', {
940 Searches the specified relationship, optionally specifying a condition and
941 attributes for matching records. See L</ATTRIBUTES> for more information.
943 In list context, C<< ->all() >> is called implicitly on the resultset, thus
944 returning a list of row objects instead. To avoid that, use L</search_related_rs>.
946 See also L</search_related_rs>.
951 return shift->related_resultset(shift)->search(@_);
954 =head2 search_related_rs
956 This method works exactly the same as search_related, except that
957 it guarantees a resultset, even in list context.
961 sub search_related_rs {
962 return shift->related_resultset(shift)->search_rs(@_);
969 =item Arguments: none
971 =item Return Value: $cursor
975 Returns a storage-driven cursor to the given resultset. See
976 L<DBIx::Class::Cursor> for more information.
983 my $attrs = $self->_resolved_attrs_copy;
985 return $self->{cursor}
986 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
987 $attrs->{where},$attrs);
994 =item Arguments: $cond?
996 =item Return Value: $row_object | undef
1000 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1002 Inflates the first result without creating a cursor if the resultset has
1003 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1006 While this method can take an optional search condition (just like L</search>)
1007 being a fast-code-path it does not recognize search attributes. If you need to
1008 add extra joins or similar, call L</search> and then chain-call L</single> on the
1009 L<DBIx::Class::ResultSet> returned.
1015 As of 0.08100, this method enforces the assumption that the preceding
1016 query returns only one row. If more than one row is returned, you will receive
1019 Query returned more than one row
1021 In this case, you should be using L</next> or L</find> instead, or if you really
1022 know what you are doing, use the L</rows> attribute to explicitly limit the size
1025 This method will also throw an exception if it is called on a resultset prefetching
1026 has_many, as such a prefetch implies fetching multiple rows from the database in
1027 order to assemble the resulting object.
1034 my ($self, $where) = @_;
1036 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1039 my $attrs = $self->_resolved_attrs_copy;
1041 if (keys %{$attrs->{collapse}}) {
1042 $self->throw_exception(
1043 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
1048 if (defined $attrs->{where}) {
1051 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1052 $where, delete $attrs->{where} ]
1055 $attrs->{where} = $where;
1059 my @data = $self->result_source->storage->select_single(
1060 $attrs->{from}, $attrs->{select},
1061 $attrs->{where}, $attrs
1064 return (@data ? ($self->_construct_object(@data))[0] : undef);
1070 # Recursively collapse the query, accumulating values for each column.
1072 sub _collapse_query {
1073 my ($self, $query, $collapsed) = @_;
1077 if (ref $query eq 'ARRAY') {
1078 foreach my $subquery (@$query) {
1079 next unless ref $subquery; # -or
1080 $collapsed = $self->_collapse_query($subquery, $collapsed);
1083 elsif (ref $query eq 'HASH') {
1084 if (keys %$query and (keys %$query)[0] eq '-and') {
1085 foreach my $subquery (@{$query->{-and}}) {
1086 $collapsed = $self->_collapse_query($subquery, $collapsed);
1090 foreach my $col (keys %$query) {
1091 my $value = $query->{$col};
1092 $collapsed->{$col}{$value}++;
1104 =item Arguments: $cond?
1106 =item Return Value: $resultsetcolumn
1110 my $max_length = $rs->get_column('length')->max;
1112 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1117 my ($self, $column) = @_;
1118 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
1126 =item Arguments: $cond, \%attrs?
1128 =item Return Value: $resultset (scalar context) || @row_objs (list context)
1132 # WHERE title LIKE '%blue%'
1133 $cd_rs = $rs->search_like({ title => '%blue%'});
1135 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1136 that this is simply a convenience method retained for ex Class::DBI users.
1137 You most likely want to use L</search> with specific operators.
1139 For more information, see L<DBIx::Class::Manual::Cookbook>.
1141 This method is deprecated and will be removed in 0.09. Use L</search()>
1142 instead. An example conversion is:
1144 ->search_like({ foo => 'bar' });
1148 ->search({ foo => { like => 'bar' } });
1155 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1156 .' Instead use ->search({ x => { -like => "y%" } })'
1157 .' (note the outer pair of {}s - they are important!)'
1159 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1160 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1161 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1162 return $class->search($query, { %$attrs });
1169 =item Arguments: $first, $last
1171 =item Return Value: $resultset (scalar context) || @row_objs (list context)
1175 Returns a resultset or object list representing a subset of elements from the
1176 resultset slice is called on. Indexes are from 0, i.e., to get the first
1177 three records, call:
1179 my ($one, $two, $three) = $rs->slice(0, 2);
1184 my ($self, $min, $max) = @_;
1185 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1186 $attrs->{offset} = $self->{attrs}{offset} || 0;
1187 $attrs->{offset} += $min;
1188 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1189 return $self->search(undef, $attrs);
1190 #my $slice = (ref $self)->new($self->result_source, $attrs);
1191 #return (wantarray ? $slice->all : $slice);
1198 =item Arguments: none
1200 =item Return Value: $result | undef
1204 Returns the next element in the resultset (C<undef> is there is none).
1206 Can be used to efficiently iterate over records in the resultset:
1208 my $rs = $schema->resultset('CD')->search;
1209 while (my $cd = $rs->next) {
1213 Note that you need to store the resultset object, and call C<next> on it.
1214 Calling C<< resultset('Table')->next >> repeatedly will always return the
1215 first record from the resultset.
1221 if (my $cache = $self->get_cache) {
1222 $self->{all_cache_position} ||= 0;
1223 return $cache->[$self->{all_cache_position}++];
1225 if ($self->{attrs}{cache}) {
1226 delete $self->{pager};
1227 $self->{all_cache_position} = 1;
1228 return ($self->all)[0];
1230 if ($self->{stashed_objects}) {
1231 my $obj = shift(@{$self->{stashed_objects}});
1232 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
1236 exists $self->{stashed_row}
1237 ? @{delete $self->{stashed_row}}
1238 : $self->cursor->next
1240 return undef unless (@row);
1241 my ($row, @more) = $self->_construct_object(@row);
1242 $self->{stashed_objects} = \@more if @more;
1246 sub _construct_object {
1247 my ($self, @row) = @_;
1249 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row)
1251 my @new = $self->result_class->inflate_result($self->result_source, @$info);
1252 @new = $self->{_attrs}{record_filter}->(@new)
1253 if exists $self->{_attrs}{record_filter};
1257 sub _collapse_result {
1258 my ($self, $as_proto, $row) = @_;
1262 # 'foo' => [ undef, 'foo' ]
1263 # 'foo.bar' => [ 'foo', 'bar' ]
1264 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
1266 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
1268 my %collapse = %{$self->{_attrs}{collapse}||{}};
1272 # if we're doing collapsing (has_many prefetch) we need to grab records
1273 # until the PK changes, so fill @pri_index. if not, we leave it empty so
1274 # we know we don't have to bother.
1276 # the reason for not using the collapse stuff directly is because if you
1277 # had for e.g. two artists in a row with no cds, the collapse info for
1278 # both would be NULL (undef) so you'd lose the second artist
1280 # store just the index so we can check the array positions from the row
1281 # without having to contruct the full hash
1283 if (keys %collapse) {
1284 my %pri = map { ($_ => 1) } $self->result_source->_pri_cols;
1285 foreach my $i (0 .. $#construct_as) {
1286 next if defined($construct_as[$i][0]); # only self table
1287 if (delete $pri{$construct_as[$i][1]}) {
1288 push(@pri_index, $i);
1290 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
1294 # no need to do an if, it'll be empty if @pri_index is empty anyway
1296 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
1300 do { # no need to check anything at the front, we always want the first row
1304 foreach my $this_as (@construct_as) {
1305 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
1308 push(@const_rows, \%const);
1310 } until ( # no pri_index => no collapse => drop straight out
1313 do { # get another row, stash it, drop out if different PK
1315 @copy = $self->cursor->next;
1316 $self->{stashed_row} = \@copy;
1318 # last thing in do block, counts as true if anything doesn't match
1320 # check xor defined first for NULL vs. NOT NULL then if one is
1321 # defined the other must be so check string equality
1324 (defined $pri_vals{$_} ^ defined $copy[$_])
1325 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
1330 my $alias = $self->{attrs}{alias};
1337 foreach my $const (@const_rows) {
1338 scalar @const_keys or do {
1339 @const_keys = sort { length($a) <=> length($b) } keys %$const;
1341 foreach my $key (@const_keys) {
1344 my @parts = split(/\./, $key);
1346 my $data = $const->{$key};
1347 foreach my $p (@parts) {
1348 $target = $target->[1]->{$p} ||= [];
1350 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
1351 # collapsing at this point and on final part
1352 my $pos = $collapse_pos{$cur};
1353 CK: foreach my $ck (@ckey) {
1354 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
1355 $collapse_pos{$cur} = $data;
1356 delete @collapse_pos{ # clear all positioning for sub-entries
1357 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
1364 if (exists $collapse{$cur}) {
1365 $target = $target->[-1];
1368 $target->[0] = $data;
1370 $info->[0] = $const->{$key};
1378 =head2 result_source
1382 =item Arguments: $result_source?
1384 =item Return Value: $result_source
1388 An accessor for the primary ResultSource object from which this ResultSet
1395 =item Arguments: $result_class?
1397 =item Return Value: $result_class
1401 An accessor for the class to use when creating row objects. Defaults to
1402 C<< result_source->result_class >> - which in most cases is the name of the
1403 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1405 Note that changing the result_class will also remove any components
1406 that were originally loaded in the source class via
1407 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1408 in the original source class will not run.
1413 my ($self, $result_class) = @_;
1414 if ($result_class) {
1415 unless (ref $result_class) { # don't fire this for an object
1416 $self->ensure_class_loaded($result_class);
1418 $self->_result_class($result_class);
1419 # THIS LINE WOULD BE A BUG - this accessor specifically exists to
1420 # permit the user to set result class on one result set only; it only
1421 # chains if provided to search()
1422 #$self->{attrs}{result_class} = $result_class if ref $self;
1424 $self->_result_class;
1431 =item Arguments: $cond, \%attrs??
1433 =item Return Value: $count
1437 Performs an SQL C<COUNT> with the same query as the resultset was built
1438 with to find the number of elements. Passing arguments is equivalent to
1439 C<< $rs->search ($cond, \%attrs)->count >>
1445 return $self->search(@_)->count if @_ and defined $_[0];
1446 return scalar @{ $self->get_cache } if $self->get_cache;
1448 my $attrs = $self->_resolved_attrs_copy;
1450 # this is a little optimization - it is faster to do the limit
1451 # adjustments in software, instead of a subquery
1452 my $rows = delete $attrs->{rows};
1453 my $offset = delete $attrs->{offset};
1456 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1457 $crs = $self->_count_subq_rs ($attrs);
1460 $crs = $self->_count_rs ($attrs);
1462 my $count = $crs->next;
1464 $count -= $offset if $offset;
1465 $count = $rows if $rows and $rows < $count;
1466 $count = 0 if ($count < 0);
1475 =item Arguments: $cond, \%attrs??
1477 =item Return Value: $count_rs
1481 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1482 This can be very handy for subqueries:
1484 ->search( { amount => $some_rs->count_rs->as_query } )
1486 As with regular resultsets the SQL query will be executed only after
1487 the resultset is accessed via L</next> or L</all>. That would return
1488 the same single value obtainable via L</count>.
1494 return $self->search(@_)->count_rs if @_;
1496 # this may look like a lack of abstraction (count() does about the same)
1497 # but in fact an _rs *must* use a subquery for the limits, as the
1498 # software based limiting can not be ported if this $rs is to be used
1499 # in a subquery itself (i.e. ->as_query)
1500 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1501 return $self->_count_subq_rs;
1504 return $self->_count_rs;
1509 # returns a ResultSetColumn object tied to the count query
1512 my ($self, $attrs) = @_;
1514 my $rsrc = $self->result_source;
1515 $attrs ||= $self->_resolved_attrs;
1517 my $tmp_attrs = { %$attrs };
1518 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1519 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1521 # overwrite the selector (supplied by the storage)
1522 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $attrs);
1523 $tmp_attrs->{as} = 'count';
1524 delete @{$tmp_attrs}{qw/columns/};
1526 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1532 # same as above but uses a subquery
1534 sub _count_subq_rs {
1535 my ($self, $attrs) = @_;
1537 my $rsrc = $self->result_source;
1538 $attrs ||= $self->_resolved_attrs;
1540 my $sub_attrs = { %$attrs };
1541 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1542 delete @{$sub_attrs}{qw/collapse columns as select _prefetch_selector_range order_by for/};
1544 # if we multi-prefetch we group_by something unique, as this is what we would
1545 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1546 if ( keys %{$attrs->{collapse}} ) {
1547 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1548 $rsrc->_identifying_column_set || $self->throw_exception(
1549 'Unable to construct a unique group_by criteria properly collapsing the '
1550 . 'has_many prefetch before count()'
1555 # Calculate subquery selector
1556 if (my $g = $sub_attrs->{group_by}) {
1558 my $sql_maker = $rsrc->storage->sql_maker;
1560 # necessary as the group_by may refer to aliased functions
1562 for my $sel (@{$attrs->{select}}) {
1563 $sel_index->{$sel->{-as}} = $sel
1564 if (ref $sel eq 'HASH' and $sel->{-as});
1567 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1568 # also look for named aggregates referred in the having clause
1569 # having often contains scalarrefs - thus parse it out entirely
1571 if ($attrs->{having}) {
1572 local $sql_maker->{having_bind};
1573 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1574 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1575 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1576 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1577 # if we don't unset it we screw up retarded but unfortunately working
1578 # 'MAX(foo.bar)' => { '>', 3 }
1579 $sql_maker->{name_sep} = '';
1582 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1584 my $sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1586 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1587 # and if all fails for an utterly naive quoted scalar-with-function
1589 $rquote $sep $lquote (.+?) $rquote
1591 [\s,] \w+ \. (\w+) [\s,]
1593 [\s,] $lquote (.+?) $rquote [\s,]
1595 push @parts, ($1 || $2 || $3); # one of them matched if we got here
1600 my $colpiece = $sel_index->{$_} || $_;
1602 # unqualify join-based group_by's. Arcane but possible query
1603 # also horrible horrible hack to alias a column (not a func.)
1604 # (probably need to introduce SQLA syntax)
1605 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1608 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1610 push @{$sub_attrs->{select}}, $colpiece;
1614 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1615 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1618 return $rsrc->resultset_class
1619 ->new ($rsrc, $sub_attrs)
1621 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1622 ->get_column ('count');
1629 =head2 count_literal
1633 =item Arguments: $sql_fragment, @bind_values
1635 =item Return Value: $count
1639 Counts the results in a literal query. Equivalent to calling L</search_literal>
1640 with the passed arguments, then L</count>.
1644 sub count_literal { shift->search_literal(@_)->count; }
1650 =item Arguments: none
1652 =item Return Value: @objects
1656 Returns all elements in the resultset.
1663 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1666 return @{ $self->get_cache } if $self->get_cache;
1670 if (keys %{$self->_resolved_attrs->{collapse}}) {
1671 # Using $self->cursor->all is really just an optimisation.
1672 # If we're collapsing has_many prefetches it probably makes
1673 # very little difference, and this is cleaner than hacking
1674 # _construct_object to survive the approach
1675 $self->cursor->reset;
1676 my @row = $self->cursor->next;
1678 push(@obj, $self->_construct_object(@row));
1679 @row = (exists $self->{stashed_row}
1680 ? @{delete $self->{stashed_row}}
1681 : $self->cursor->next);
1684 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1687 $self->set_cache(\@obj) if $self->{attrs}{cache};
1696 =item Arguments: none
1698 =item Return Value: $self
1702 Resets the resultset's cursor, so you can iterate through the elements again.
1703 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1710 delete $self->{_attrs} if exists $self->{_attrs};
1711 $self->{all_cache_position} = 0;
1712 $self->cursor->reset;
1720 =item Arguments: none
1722 =item Return Value: $object | undef
1726 Resets the resultset and returns an object for the first result (or C<undef>
1727 if the resultset is empty).
1732 return $_[0]->reset->next;
1738 # Determines whether and what type of subquery is required for the $rs operation.
1739 # If grouping is necessary either supplies its own, or verifies the current one
1740 # After all is done delegates to the proper storage method.
1742 sub _rs_update_delete {
1743 my ($self, $op, $values) = @_;
1745 my $cond = $self->{cond};
1746 my $rsrc = $self->result_source;
1747 my $storage = $rsrc->schema->storage;
1749 my $attrs = { %{$self->_resolved_attrs} };
1751 # "needs" is a strong word here - if the subquery is part of an IN clause - no point of
1752 # even adding the group_by. It will really be used only when composing a poor-man's
1753 # multicolumn-IN equivalent OR set
1754 my $needs_group_by_subq = defined $attrs->{group_by};
1756 # simplify the joinmap and maybe decide if a grouping (and thus subquery) is necessary
1757 my $relation_classifications;
1758 if (ref($attrs->{from}) eq 'ARRAY') {
1759 $attrs->{from} = $storage->_prune_unused_joins ($attrs->{from}, $attrs->{select}, $cond, $attrs);
1761 $relation_classifications = $storage->_resolve_aliastypes_from_select_args (
1762 [ @{$attrs->{from}}[1 .. $#{$attrs->{from}}] ],
1766 ) unless $needs_group_by_subq; # we already know we need a group, no point of resolving them
1769 $needs_group_by_subq ||= 1; # if {from} is unparseable assume the worst
1772 $needs_group_by_subq ||= exists $relation_classifications->{multiplying};
1774 # if no subquery - life is easy-ish
1776 $needs_group_by_subq
1778 keys %$relation_classifications # if any joins at all - need to wrap a subq
1780 $self->_has_resolved_attr(qw/rows offset/) # limits call for a subq
1782 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1783 # a condition containing 'me' or other table prefixes will not work
1784 # at all. What this code tries to do (badly) is to generate a condition
1785 # with the qualifiers removed, by exploiting the quote mechanism of sqla
1787 # this is atrocious and should be replaced by normal sqla introspection
1789 my ($sql, @bind) = do {
1790 my $sqla = $rsrc->storage->sql_maker;
1791 local $sqla->{_dequalify_idents} = 1;
1792 $sqla->_recurse_where($self->{cond});
1795 return $rsrc->storage->$op(
1797 $op eq 'update' ? $values : (),
1798 $self->{cond} ? \[$sql, @bind] : (),
1802 # we got this far - means it is time to wrap a subquery
1803 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1805 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1810 my $existing_group_by = delete $attrs->{group_by};
1812 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1813 delete $attrs->{$_} for qw/collapse _collapse_order_by select _prefetch_selector_range as/;
1814 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1815 $attrs->{group_by} = \ ''; # FIXME - this is an evil hack, it causes the optimiser to kick in and throw away the LEFT joins
1816 my $subrs = (ref $self)->new($rsrc, $attrs);
1818 if (@$idcols == 1) {
1819 return $storage->$op (
1821 $op eq 'update' ? $values : (),
1822 { $idcols->[0] => { -in => $subrs->as_query } },
1825 elsif ($storage->_use_multicolumn_in) {
1826 # This is hideously ugly, but SQLA does not understand multicol IN expressions
1827 my $sql_maker = $storage->sql_maker;
1828 my ($sql, @bind) = @${$subrs->as_query};
1829 $sql = sprintf ('(%s) IN %s', # the as_query already comes with a set of parenthesis
1830 join (', ', map { $sql_maker->_quote ($_) } @$idcols),
1834 return $storage->$op (
1836 $op eq 'update' ? $values : (),
1841 # if all else fails - get all primary keys and operate over a ORed set
1842 # wrap in a transaction for consistency
1843 # this is where the group_by starts to matter
1845 if ($needs_group_by_subq) {
1846 $subq_group_by = $attrs->{columns};
1848 # make sure if there is a supplied group_by it matches the columns compiled above
1849 # perfectly. Anything else can not be sanely executed on most databases so croak
1850 # right then and there
1851 if ($existing_group_by) {
1852 my @current_group_by = map
1853 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1858 join ("\x00", sort @current_group_by)
1860 join ("\x00", sort @$subq_group_by )
1862 $self->throw_exception (
1863 "You have just attempted a $op operation on a resultset which does group_by"
1864 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1865 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1866 . ' kind of queries. Please retry the operation with a modified group_by or'
1867 . ' without using one at all.'
1873 my $guard = $storage->txn_scope_guard;
1876 for my $row ($subrs->search({}, { group_by => $subq_group_by })->cursor->all) {
1877 push @op_condition, { map
1878 { $idcols->[$_] => $row->[$_] }
1883 my $res = $storage->$op (
1885 $op eq 'update' ? $values : (),
1899 =item Arguments: \%values
1901 =item Return Value: $storage_rv
1905 Sets the specified columns in the resultset to the supplied values in a
1906 single query. Note that this will not run any accessor/set_column/update
1907 triggers, nor will it update any row object instances derived from this
1908 resultset (this includes the contents of the L<resultset cache|/set_cache>
1909 if any). See L</update_all> if you need to execute any on-update
1910 triggers or cascades defined either by you or a
1911 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1913 The return value is a pass through of what the underlying
1914 storage backend returned, and may vary. See L<DBI/execute> for the most
1919 Note that L</update> does not process/deflate any of the values passed in.
1920 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
1921 ensure manually that any value passed to this method will stringify to
1922 something the RDBMS knows how to deal with. A notable example is the
1923 handling of L<DateTime> objects, for more info see:
1924 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
1929 my ($self, $values) = @_;
1930 $self->throw_exception('Values for update must be a hash')
1931 unless ref $values eq 'HASH';
1933 return $self->_rs_update_delete ('update', $values);
1940 =item Arguments: \%values
1942 =item Return Value: 1
1946 Fetches all objects and updates them one at a time via
1947 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
1948 triggers, while L</update> will not.
1953 my ($self, $values) = @_;
1954 $self->throw_exception('Values for update_all must be a hash')
1955 unless ref $values eq 'HASH';
1957 my $guard = $self->result_source->schema->txn_scope_guard;
1958 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
1967 =item Arguments: none
1969 =item Return Value: $storage_rv
1973 Deletes the rows matching this resultset in a single query. Note that this
1974 will not run any delete triggers, nor will it alter the
1975 L<in_storage|DBIx::Class::Row/in_storage> status of any row object instances
1976 derived from this resultset (this includes the contents of the
1977 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
1978 execute any on-delete triggers or cascades defined either by you or a
1979 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1981 The return value is a pass through of what the underlying storage backend
1982 returned, and may vary. See L<DBI/execute> for the most common case.
1988 $self->throw_exception('delete does not accept any arguments')
1991 return $self->_rs_update_delete ('delete');
1998 =item Arguments: none
2000 =item Return Value: 1
2004 Fetches all objects and deletes them one at a time via
2005 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2006 triggers, while L</delete> will not.
2012 $self->throw_exception('delete_all does not accept any arguments')
2015 my $guard = $self->result_source->schema->txn_scope_guard;
2016 $_->delete for $self->all;
2025 =item Arguments: \@data;
2029 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
2030 For the arrayref of hashrefs style each hashref should be a structure suitable
2031 for submitting to a $resultset->create(...) method.
2033 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
2034 to insert the data, as this is a faster method.
2036 Otherwise, each set of data is inserted into the database using
2037 L<DBIx::Class::ResultSet/create>, and the resulting objects are
2038 accumulated into an array. The array itself, or an array reference
2039 is returned depending on scalar or list context.
2041 Example: Assuming an Artist Class that has many CDs Classes relating:
2043 my $Artist_rs = $schema->resultset("Artist");
2045 ## Void Context Example
2046 $Artist_rs->populate([
2047 { artistid => 4, name => 'Manufactured Crap', cds => [
2048 { title => 'My First CD', year => 2006 },
2049 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2052 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2053 { title => 'My parents sold me to a record company', year => 2005 },
2054 { title => 'Why Am I So Ugly?', year => 2006 },
2055 { title => 'I Got Surgery and am now Popular', year => 2007 }
2060 ## Array Context Example
2061 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
2062 { name => "Artist One"},
2063 { name => "Artist Two"},
2064 { name => "Artist Three", cds=> [
2065 { title => "First CD", year => 2007},
2066 { title => "Second CD", year => 2008},
2070 print $ArtistOne->name; ## response is 'Artist One'
2071 print $ArtistThree->cds->count ## reponse is '2'
2073 For the arrayref of arrayrefs style, the first element should be a list of the
2074 fieldsnames to which the remaining elements are rows being inserted. For
2077 $Arstist_rs->populate([
2078 [qw/artistid name/],
2079 [100, 'A Formally Unknown Singer'],
2080 [101, 'A singer that jumped the shark two albums ago'],
2081 [102, 'An actually cool singer'],
2084 Please note an important effect on your data when choosing between void and
2085 wantarray context. Since void context goes straight to C<insert_bulk> in
2086 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
2087 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
2088 create primary keys for you, you will find that your PKs are empty. In this
2089 case you will have to use the wantarray context in order to create those
2097 # cruft placed in standalone method
2098 my $data = $self->_normalize_populate_args(@_);
2100 return unless @$data;
2102 if(defined wantarray) {
2104 foreach my $item (@$data) {
2105 push(@created, $self->create($item));
2107 return wantarray ? @created : \@created;
2110 my $first = $data->[0];
2112 # if a column is a registered relationship, and is a non-blessed hash/array, consider
2113 # it relationship data
2114 my (@rels, @columns);
2115 my $rsrc = $self->result_source;
2116 my $rels = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2117 for (keys %$first) {
2118 my $ref = ref $first->{$_};
2119 $rels->{$_} && ($ref eq 'ARRAY' or $ref eq 'HASH')
2125 my @pks = $rsrc->primary_columns;
2127 ## do the belongs_to relationships
2128 foreach my $index (0..$#$data) {
2130 # delegate to create() for any dataset without primary keys with specified relationships
2131 if (grep { !defined $data->[$index]->{$_} } @pks ) {
2133 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
2134 my @ret = $self->populate($data);
2140 foreach my $rel (@rels) {
2141 next unless ref $data->[$index]->{$rel} eq "HASH";
2142 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
2143 my ($reverse_relname, $reverse_relinfo) = %{$rsrc->reverse_relationship_info($rel)};
2144 my $related = $result->result_source->_resolve_condition(
2145 $reverse_relinfo->{cond},
2151 delete $data->[$index]->{$rel};
2152 $data->[$index] = {%{$data->[$index]}, %$related};
2154 push @columns, keys %$related if $index == 0;
2158 ## inherit the data locked in the conditions of the resultset
2159 my ($rs_data) = $self->_merge_with_rscond({});
2160 delete @{$rs_data}{@columns};
2161 my @inherit_cols = keys %$rs_data;
2162 my @inherit_data = values %$rs_data;
2164 ## do bulk insert on current row
2165 $rsrc->storage->insert_bulk(
2167 [@columns, @inherit_cols],
2168 [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
2171 ## do the has_many relationships
2172 foreach my $item (@$data) {
2176 foreach my $rel (@rels) {
2177 next unless ref $item->{$rel} eq "ARRAY" && @{ $item->{$rel} };
2179 $main_row ||= $self->new_result({map { $_ => $item->{$_} } @pks});
2181 my $child = $main_row->$rel;
2183 my $related = $child->result_source->_resolve_condition(
2184 $rels->{$rel}{cond},
2190 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
2191 my @populate = map { {%$_, %$related} } @rows_to_add;
2193 $child->populate( \@populate );
2200 # populate() argumnets went over several incarnations
2201 # What we ultimately support is AoH
2202 sub _normalize_populate_args {
2203 my ($self, $arg) = @_;
2205 if (ref $arg eq 'ARRAY') {
2209 elsif (ref $arg->[0] eq 'HASH') {
2212 elsif (ref $arg->[0] eq 'ARRAY') {
2214 my @colnames = @{$arg->[0]};
2215 foreach my $values (@{$arg}[1 .. $#$arg]) {
2216 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
2222 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2229 =item Arguments: none
2231 =item Return Value: $pager
2235 Return Value a L<Data::Page> object for the current resultset. Only makes
2236 sense for queries with a C<page> attribute.
2238 To get the full count of entries for a paged resultset, call
2239 C<total_entries> on the L<Data::Page> object.
2246 return $self->{pager} if $self->{pager};
2248 my $attrs = $self->{attrs};
2249 if (!defined $attrs->{page}) {
2250 $self->throw_exception("Can't create pager for non-paged rs");
2252 elsif ($attrs->{page} <= 0) {
2253 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2255 $attrs->{rows} ||= 10;
2257 # throw away the paging flags and re-run the count (possibly
2258 # with a subselect) to get the real total count
2259 my $count_attrs = { %$attrs };
2260 delete $count_attrs->{$_} for qw/rows offset page pager/;
2262 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2264 require DBIx::Class::ResultSet::Pager;
2265 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2266 sub { $total_rs->count }, #lazy-get the total
2268 $self->{attrs}{page},
2276 =item Arguments: $page_number
2278 =item Return Value: $rs
2282 Returns a resultset for the $page_number page of the resultset on which page
2283 is called, where each page contains a number of rows equal to the 'rows'
2284 attribute set on the resultset (10 by default).
2289 my ($self, $page) = @_;
2290 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2297 =item Arguments: \%vals
2299 =item Return Value: $rowobject
2303 Creates a new row object in the resultset's result class and returns
2304 it. The row is not inserted into the database at this point, call
2305 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2306 will tell you whether the row object has been inserted or not.
2308 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2313 my ($self, $values) = @_;
2314 $self->throw_exception( "new_result needs a hash" )
2315 unless (ref $values eq 'HASH');
2317 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2321 @$cols_from_relations
2322 ? (-cols_from_relations => $cols_from_relations)
2324 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2327 return $self->result_class->new(\%new);
2330 # _merge_with_rscond
2332 # Takes a simple hash of K/V data and returns its copy merged with the
2333 # condition already present on the resultset. Additionally returns an
2334 # arrayref of value/condition names, which were inferred from related
2335 # objects (this is needed for in-memory related objects)
2336 sub _merge_with_rscond {
2337 my ($self, $data) = @_;
2339 my (%new_data, @cols_from_relations);
2341 my $alias = $self->{attrs}{alias};
2343 if (! defined $self->{cond}) {
2344 # just massage $data below
2346 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
2347 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
2348 @cols_from_relations = keys %new_data;
2350 elsif (ref $self->{cond} ne 'HASH') {
2351 $self->throw_exception(
2352 "Can't abstract implicit construct, resultset condition not a hash"
2356 # precendence must be given to passed values over values inherited from
2357 # the cond, so the order here is important.
2358 my $collapsed_cond = $self->_collapse_cond($self->{cond});
2359 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
2361 while ( my($col, $value) = each %implied ) {
2362 my $vref = ref $value;
2368 (keys %$value)[0] eq '='
2370 $new_data{$col} = $value->{'='};
2372 elsif( !$vref or $vref eq 'SCALAR' or blessed($value) ) {
2373 $new_data{$col} = $value;
2380 %{ $self->_remove_alias($data, $alias) },
2383 return (\%new_data, \@cols_from_relations);
2386 # _has_resolved_attr
2388 # determines if the resultset defines at least one
2389 # of the attributes supplied
2391 # used to determine if a subquery is neccessary
2393 # supports some virtual attributes:
2395 # This will scan for any joins being present on the resultset.
2396 # It is not a mere key-search but a deep inspection of {from}
2399 sub _has_resolved_attr {
2400 my ($self, @attr_names) = @_;
2402 my $attrs = $self->_resolved_attrs;
2406 for my $n (@attr_names) {
2407 if (grep { $n eq $_ } (qw/-join/) ) {
2408 $extra_checks{$n}++;
2412 my $attr = $attrs->{$n};
2414 next if not defined $attr;
2416 if (ref $attr eq 'HASH') {
2417 return 1 if keys %$attr;
2419 elsif (ref $attr eq 'ARRAY') {
2427 # a resolved join is expressed as a multi-level from
2429 $extra_checks{-join}
2431 ref $attrs->{from} eq 'ARRAY'
2433 @{$attrs->{from}} > 1
2441 # Recursively collapse the condition.
2443 sub _collapse_cond {
2444 my ($self, $cond, $collapsed) = @_;
2448 if (ref $cond eq 'ARRAY') {
2449 foreach my $subcond (@$cond) {
2450 next unless ref $subcond; # -or
2451 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2454 elsif (ref $cond eq 'HASH') {
2455 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2456 foreach my $subcond (@{$cond->{-and}}) {
2457 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2461 foreach my $col (keys %$cond) {
2462 my $value = $cond->{$col};
2463 $collapsed->{$col} = $value;
2473 # Remove the specified alias from the specified query hash. A copy is made so
2474 # the original query is not modified.
2477 my ($self, $query, $alias) = @_;
2479 my %orig = %{ $query || {} };
2482 foreach my $key (keys %orig) {
2484 $unaliased{$key} = $orig{$key};
2487 $unaliased{$1} = $orig{$key}
2488 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2498 =item Arguments: none
2500 =item Return Value: \[ $sql, @bind ]
2504 Returns the SQL query and bind vars associated with the invocant.
2506 This is generally used as the RHS for a subquery.
2513 my $attrs = $self->_resolved_attrs_copy;
2518 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2519 # $sql also has no wrapping parenthesis in list ctx
2521 my $sqlbind = $self->result_source->storage
2522 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2531 =item Arguments: \%vals, \%attrs?
2533 =item Return Value: $rowobject
2537 my $artist = $schema->resultset('Artist')->find_or_new(
2538 { artist => 'fred' }, { key => 'artists' });
2540 $cd->cd_to_producer->find_or_new({ producer => $producer },
2541 { key => 'primary });
2543 Find an existing record from this resultset using L</find>. if none exists,
2544 instantiate a new result object and return it. The object will not be saved
2545 into your storage until you call L<DBIx::Class::Row/insert> on it.
2547 You most likely want this method when looking for existing rows using a unique
2548 constraint that is not the primary key, or looking for related rows.
2550 If you want objects to be saved immediately, use L</find_or_create> instead.
2552 B<Note>: Make sure to read the documentation of L</find> and understand the
2553 significance of the C<key> attribute, as its lack may skew your search, and
2554 subsequently result in spurious new objects.
2556 B<Note>: Take care when using C<find_or_new> with a table having
2557 columns with default values that you intend to be automatically
2558 supplied by the database (e.g. an auto_increment primary key column).
2559 In normal usage, the value of such columns should NOT be included at
2560 all in the call to C<find_or_new>, even when set to C<undef>.
2566 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2567 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2568 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2571 return $self->new_result($hash);
2578 =item Arguments: \%vals
2580 =item Return Value: a L<DBIx::Class::Row> $object
2584 Attempt to create a single new row or a row with multiple related rows
2585 in the table represented by the resultset (and related tables). This
2586 will not check for duplicate rows before inserting, use
2587 L</find_or_create> to do that.
2589 To create one row for this resultset, pass a hashref of key/value
2590 pairs representing the columns of the table and the values you wish to
2591 store. If the appropriate relationships are set up, foreign key fields
2592 can also be passed an object representing the foreign row, and the
2593 value will be set to its primary key.
2595 To create related objects, pass a hashref of related-object column values
2596 B<keyed on the relationship name>. If the relationship is of type C<multi>
2597 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2598 The process will correctly identify columns holding foreign keys, and will
2599 transparently populate them from the keys of the corresponding relation.
2600 This can be applied recursively, and will work correctly for a structure
2601 with an arbitrary depth and width, as long as the relationships actually
2602 exists and the correct column data has been supplied.
2605 Instead of hashrefs of plain related data (key/value pairs), you may
2606 also pass new or inserted objects. New objects (not inserted yet, see
2607 L</new>), will be inserted into their appropriate tables.
2609 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2611 Example of creating a new row.
2613 $person_rs->create({
2614 name=>"Some Person",
2615 email=>"somebody@someplace.com"
2618 Example of creating a new row and also creating rows in a related C<has_many>
2619 or C<has_one> resultset. Note Arrayref.
2622 { artistid => 4, name => 'Manufactured Crap', cds => [
2623 { title => 'My First CD', year => 2006 },
2624 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2629 Example of creating a new row and also creating a row in a related
2630 C<belongs_to> resultset. Note Hashref.
2633 title=>"Music for Silly Walks",
2636 name=>"Silly Musician",
2644 When subclassing ResultSet never attempt to override this method. Since
2645 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2646 lot of the internals simply never call it, so your override will be
2647 bypassed more often than not. Override either L<new|DBIx::Class::Row/new>
2648 or L<insert|DBIx::Class::Row/insert> depending on how early in the
2649 L</create> process you need to intervene.
2656 my ($self, $attrs) = @_;
2657 $self->throw_exception( "create needs a hashref" )
2658 unless ref $attrs eq 'HASH';
2659 return $self->new_result($attrs)->insert;
2662 =head2 find_or_create
2666 =item Arguments: \%vals, \%attrs?
2668 =item Return Value: $rowobject
2672 $cd->cd_to_producer->find_or_create({ producer => $producer },
2673 { key => 'primary' });
2675 Tries to find a record based on its primary key or unique constraints; if none
2676 is found, creates one and returns that instead.
2678 my $cd = $schema->resultset('CD')->find_or_create({
2680 artist => 'Massive Attack',
2681 title => 'Mezzanine',
2685 Also takes an optional C<key> attribute, to search by a specific key or unique
2686 constraint. For example:
2688 my $cd = $schema->resultset('CD')->find_or_create(
2690 artist => 'Massive Attack',
2691 title => 'Mezzanine',
2693 { key => 'cd_artist_title' }
2696 B<Note>: Make sure to read the documentation of L</find> and understand the
2697 significance of the C<key> attribute, as its lack may skew your search, and
2698 subsequently result in spurious row creation.
2700 B<Note>: Because find_or_create() reads from the database and then
2701 possibly inserts based on the result, this method is subject to a race
2702 condition. Another process could create a record in the table after
2703 the find has completed and before the create has started. To avoid
2704 this problem, use find_or_create() inside a transaction.
2706 B<Note>: Take care when using C<find_or_create> with a table having
2707 columns with default values that you intend to be automatically
2708 supplied by the database (e.g. an auto_increment primary key column).
2709 In normal usage, the value of such columns should NOT be included at
2710 all in the call to C<find_or_create>, even when set to C<undef>.
2712 See also L</find> and L</update_or_create>. For information on how to declare
2713 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2717 sub find_or_create {
2719 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2720 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2721 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2724 return $self->create($hash);
2727 =head2 update_or_create
2731 =item Arguments: \%col_values, { key => $unique_constraint }?
2733 =item Return Value: $row_object
2737 $resultset->update_or_create({ col => $val, ... });
2739 Like L</find_or_create>, but if a row is found it is immediately updated via
2740 C<< $found_row->update (\%col_values) >>.
2743 Takes an optional C<key> attribute to search on a specific unique constraint.
2746 # In your application
2747 my $cd = $schema->resultset('CD')->update_or_create(
2749 artist => 'Massive Attack',
2750 title => 'Mezzanine',
2753 { key => 'cd_artist_title' }
2756 $cd->cd_to_producer->update_or_create({
2757 producer => $producer,
2763 B<Note>: Make sure to read the documentation of L</find> and understand the
2764 significance of the C<key> attribute, as its lack may skew your search, and
2765 subsequently result in spurious row creation.
2767 B<Note>: Take care when using C<update_or_create> with a table having
2768 columns with default values that you intend to be automatically
2769 supplied by the database (e.g. an auto_increment primary key column).
2770 In normal usage, the value of such columns should NOT be included at
2771 all in the call to C<update_or_create>, even when set to C<undef>.
2773 See also L</find> and L</find_or_create>. For information on how to declare
2774 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2778 sub update_or_create {
2780 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2781 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2783 my $row = $self->find($cond, $attrs);
2785 $row->update($cond);
2789 return $self->create($cond);
2792 =head2 update_or_new
2796 =item Arguments: \%col_values, { key => $unique_constraint }?
2798 =item Return Value: $rowobject
2802 $resultset->update_or_new({ col => $val, ... });
2804 Like L</find_or_new> but if a row is found it is immediately updated via
2805 C<< $found_row->update (\%col_values) >>.
2809 # In your application
2810 my $cd = $schema->resultset('CD')->update_or_new(
2812 artist => 'Massive Attack',
2813 title => 'Mezzanine',
2816 { key => 'cd_artist_title' }
2819 if ($cd->in_storage) {
2820 # the cd was updated
2823 # the cd is not yet in the database, let's insert it
2827 B<Note>: Make sure to read the documentation of L</find> and understand the
2828 significance of the C<key> attribute, as its lack may skew your search, and
2829 subsequently result in spurious new objects.
2831 B<Note>: Take care when using C<update_or_new> with a table having
2832 columns with default values that you intend to be automatically
2833 supplied by the database (e.g. an auto_increment primary key column).
2834 In normal usage, the value of such columns should NOT be included at
2835 all in the call to C<update_or_new>, even when set to C<undef>.
2837 See also L</find>, L</find_or_create> and L</find_or_new>.
2843 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2844 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2846 my $row = $self->find( $cond, $attrs );
2847 if ( defined $row ) {
2848 $row->update($cond);
2852 return $self->new_result($cond);
2859 =item Arguments: none
2861 =item Return Value: \@cache_objects | undef
2865 Gets the contents of the cache for the resultset, if the cache is set.
2867 The cache is populated either by using the L</prefetch> attribute to
2868 L</search> or by calling L</set_cache>.
2880 =item Arguments: \@cache_objects
2882 =item Return Value: \@cache_objects
2886 Sets the contents of the cache for the resultset. Expects an arrayref
2887 of objects of the same class as those produced by the resultset. Note that
2888 if the cache is set the resultset will return the cached objects rather
2889 than re-querying the database even if the cache attr is not set.
2891 The contents of the cache can also be populated by using the
2892 L</prefetch> attribute to L</search>.
2897 my ( $self, $data ) = @_;
2898 $self->throw_exception("set_cache requires an arrayref")
2899 if defined($data) && (ref $data ne 'ARRAY');
2900 $self->{all_cache} = $data;
2907 =item Arguments: none
2909 =item Return Value: undef
2913 Clears the cache for the resultset.
2918 shift->set_cache(undef);
2925 =item Arguments: none
2927 =item Return Value: true, if the resultset has been paginated
2935 return !!$self->{attrs}{page};
2942 =item Arguments: none
2944 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2952 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
2955 =head2 related_resultset
2959 =item Arguments: $relationship_name
2961 =item Return Value: $resultset
2965 Returns a related resultset for the supplied relationship name.
2967 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2971 sub related_resultset {
2972 my ($self, $rel) = @_;
2974 $self->{related_resultsets} ||= {};
2975 return $self->{related_resultsets}{$rel} ||= do {
2976 my $rsrc = $self->result_source;
2977 my $rel_info = $rsrc->relationship_info($rel);
2979 $self->throw_exception(
2980 "search_related: result source '" . $rsrc->source_name .
2981 "' has no such relationship $rel")
2984 my $attrs = $self->_chain_relationship($rel);
2986 my $join_count = $attrs->{seen_join}{$rel};
2988 my $alias = $self->result_source->storage
2989 ->relname_to_table_alias($rel, $join_count);
2991 # since this is search_related, and we already slid the select window inwards
2992 # (the select/as attrs were deleted in the beginning), we need to flip all
2993 # left joins to inner, so we get the expected results
2994 # read the comment on top of the actual function to see what this does
2995 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
2998 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2999 delete @{$attrs}{qw(result_class alias)};
3003 if (my $cache = $self->get_cache) {
3004 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
3005 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
3010 my $rel_source = $rsrc->related_source($rel);
3014 # The reason we do this now instead of passing the alias to the
3015 # search_rs below is that if you wrap/overload resultset on the
3016 # source you need to know what alias it's -going- to have for things
3017 # to work sanely (e.g. RestrictWithObject wants to be able to add
3018 # extra query restrictions, and these may need to be $alias.)
3020 my $rel_attrs = $rel_source->resultset_attributes;
3021 local $rel_attrs->{alias} = $alias;
3023 $rel_source->resultset
3027 where => $attrs->{where},
3030 $new->set_cache($new_cache) if $new_cache;
3035 =head2 current_source_alias
3039 =item Arguments: none
3041 =item Return Value: $source_alias
3045 Returns the current table alias for the result source this resultset is built
3046 on, that will be used in the SQL query. Usually it is C<me>.
3048 Currently the source alias that refers to the result set returned by a
3049 L</search>/L</find> family method depends on how you got to the resultset: it's
3050 C<me> by default, but eg. L</search_related> aliases it to the related result
3051 source name (and keeps C<me> referring to the original result set). The long
3052 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3053 (and make this method unnecessary).
3055 Thus it's currently necessary to use this method in predefined queries (see
3056 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3057 source alias of the current result set:
3059 # in a result set class
3061 my ($self, $user) = @_;
3063 my $me = $self->current_source_alias;
3065 return $self->search(
3066 "$me.modified" => $user->id,
3072 sub current_source_alias {
3075 return ($self->{attrs} || {})->{alias} || 'me';
3078 =head2 as_subselect_rs
3082 =item Arguments: none
3084 =item Return Value: $resultset
3088 Act as a barrier to SQL symbols. The resultset provided will be made into a
3089 "virtual view" by including it as a subquery within the from clause. From this
3090 point on, any joined tables are inaccessible to ->search on the resultset (as if
3091 it were simply where-filtered without joins). For example:
3093 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3095 # 'x' now pollutes the query namespace
3097 # So the following works as expected
3098 my $ok_rs = $rs->search({'x.other' => 1});
3100 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3101 # def) we look for one row with contradictory terms and join in another table
3102 # (aliased 'x_2') which we never use
3103 my $broken_rs = $rs->search({'x.name' => 'def'});
3105 my $rs2 = $rs->as_subselect_rs;
3107 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3108 my $not_joined_rs = $rs2->search({'x.other' => 1});
3110 # works as expected: finds a 'table' row related to two x rows (abc and def)
3111 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3113 Another example of when one might use this would be to select a subset of
3114 columns in a group by clause:
3116 my $rs = $schema->resultset('Bar')->search(undef, {
3117 group_by => [qw{ id foo_id baz_id }],
3118 })->as_subselect_rs->search(undef, {
3119 columns => [qw{ id foo_id }]
3122 In the above example normally columns would have to be equal to the group by,
3123 but because we isolated the group by into a subselect the above works.
3127 sub as_subselect_rs {
3130 my $attrs = $self->_resolved_attrs;
3132 my $fresh_rs = (ref $self)->new (
3133 $self->result_source
3136 # these pieces will be locked in the subquery
3137 delete $fresh_rs->{cond};
3138 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3140 return $fresh_rs->search( {}, {
3142 $attrs->{alias} => $self->as_query,
3143 -alias => $attrs->{alias},
3144 -rsrc => $self->result_source,
3146 alias => $attrs->{alias},
3150 # This code is called by search_related, and makes sure there
3151 # is clear separation between the joins before, during, and
3152 # after the relationship. This information is needed later
3153 # in order to properly resolve prefetch aliases (any alias
3154 # with a relation_chain_depth less than the depth of the
3155 # current prefetch is not considered)
3157 # The increments happen twice per join. An even number means a
3158 # relationship specified via a search_related, whereas an odd
3159 # number indicates a join/prefetch added via attributes
3161 # Also this code will wrap the current resultset (the one we
3162 # chain to) in a subselect IFF it contains limiting attributes
3163 sub _chain_relationship {
3164 my ($self, $rel) = @_;
3165 my $source = $self->result_source;
3166 my $attrs = { %{$self->{attrs}||{}} };
3168 # we need to take the prefetch the attrs into account before we
3169 # ->_resolve_join as otherwise they get lost - captainL
3170 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3172 delete @{$attrs}{qw/join prefetch collapse group_by distinct select as columns +select +as +columns/};
3174 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3177 my @force_subq_attrs = qw/offset rows group_by having/;
3180 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3182 $self->_has_resolved_attr (@force_subq_attrs)
3184 # Nuke the prefetch (if any) before the new $rs attrs
3185 # are resolved (prefetch is useless - we are wrapping
3186 # a subquery anyway).
3187 my $rs_copy = $self->search;
3188 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3189 $rs_copy->{attrs}{join},
3190 delete $rs_copy->{attrs}{prefetch},
3195 -alias => $attrs->{alias},
3196 $attrs->{alias} => $rs_copy->as_query,
3198 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3199 $seen->{-relation_chain_depth} = 0;
3201 elsif ($attrs->{from}) { #shallow copy suffices
3202 $from = [ @{$attrs->{from}} ];
3207 -alias => $attrs->{alias},
3208 $attrs->{alias} => $source->from,
3212 my $jpath = ($seen->{-relation_chain_depth})
3213 ? $from->[-1][0]{-join_path}
3216 my @requested_joins = $source->_resolve_join(
3223 push @$from, @requested_joins;
3225 $seen->{-relation_chain_depth}++;
3227 # if $self already had a join/prefetch specified on it, the requested
3228 # $rel might very well be already included. What we do in this case
3229 # is effectively a no-op (except that we bump up the chain_depth on
3230 # the join in question so we could tell it *is* the search_related)
3233 # we consider the last one thus reverse
3234 for my $j (reverse @requested_joins) {
3235 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3236 if ($rel eq $last_j) {
3237 $j->[0]{-relation_chain_depth}++;
3243 unless ($already_joined) {
3244 push @$from, $source->_resolve_join(
3252 $seen->{-relation_chain_depth}++;
3254 return {%$attrs, from => $from, seen_join => $seen};
3257 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
3258 sub _resolved_attrs_copy {
3260 return { %{$self->_resolved_attrs (@_)} };
3263 sub _resolved_attrs {
3265 return $self->{_attrs} if $self->{_attrs};
3267 my $attrs = { %{ $self->{attrs} || {} } };
3268 my $source = $self->result_source;
3269 my $alias = $attrs->{alias};
3271 # default selection list
3272 $attrs->{columns} = [ $source->columns ]
3273 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3275 # merge selectors together
3276 for (qw/columns select as/) {
3277 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3278 if $attrs->{$_} or $attrs->{"+$_"};
3281 # disassemble columns
3283 if (my $cols = delete $attrs->{columns}) {
3284 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3285 if (ref $c eq 'HASH') {
3286 for my $as (keys %$c) {
3287 push @sel, $c->{$as};
3298 # when trying to weed off duplicates later do not go past this point -
3299 # everything added from here on is unbalanced "anyone's guess" stuff
3300 my $dedup_stop_idx = $#as;
3302 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3304 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3305 if $attrs->{select};
3307 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3309 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_";
3312 # disqualify all $alias.col as-bits (collapser mandated)
3314 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_;
3317 # de-duplicate the result (remove *identical* select/as pairs)
3318 # and also die on duplicate {as} pointing to different {select}s
3319 # not using a c-style for as the condition is prone to shrinkage
3322 while ($i <= $dedup_stop_idx) {
3323 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3328 elsif ($seen->{$as[$i]}++) {
3329 $self->throw_exception(
3330 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3338 $attrs->{select} = \@sel;
3339 $attrs->{as} = \@as;
3341 $attrs->{from} ||= [{
3343 -alias => $self->{attrs}{alias},
3344 $self->{attrs}{alias} => $source->from,
3347 if ( $attrs->{join} || $attrs->{prefetch} ) {
3349 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3350 if ref $attrs->{from} ne 'ARRAY';
3352 my $join = (delete $attrs->{join}) || {};
3354 if ( defined $attrs->{prefetch} ) {
3355 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3358 $attrs->{from} = # have to copy here to avoid corrupting the original
3360 @{ $attrs->{from} },
3361 $source->_resolve_join(
3364 { %{ $attrs->{seen_join} || {} } },
3365 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3366 ? $attrs->{from}[-1][0]{-join_path}
3373 if ( defined $attrs->{order_by} ) {
3374 $attrs->{order_by} = (
3375 ref( $attrs->{order_by} ) eq 'ARRAY'
3376 ? [ @{ $attrs->{order_by} } ]
3377 : [ $attrs->{order_by} || () ]
3381 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3382 $attrs->{group_by} = [ $attrs->{group_by} ];
3385 # generate the distinct induced group_by early, as prefetch will be carried via a
3386 # subquery (since a group_by is present)
3387 if (delete $attrs->{distinct}) {
3388 if ($attrs->{group_by}) {
3389 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3392 # distinct affects only the main selection part, not what prefetch may
3394 $attrs->{group_by} = $source->storage->_group_over_selection (
3402 $attrs->{collapse} ||= {};
3403 if ($attrs->{prefetch}) {
3405 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3406 if $attrs->{_dark_selector};
3408 my $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} );
3410 my $prefetch_ordering = [];
3412 # this is a separate structure (we don't look in {from} directly)
3413 # as the resolver needs to shift things off the lists to work
3414 # properly (identical-prefetches on different branches)
3416 if (ref $attrs->{from} eq 'ARRAY') {
3418 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3420 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3421 next unless $j->[0]{-alias};
3422 next unless $j->[0]{-join_path};
3423 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3425 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3428 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3429 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3434 $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
3436 # we need to somehow mark which columns came from prefetch
3438 my $sel_end = $#{$attrs->{select}};
3439 $attrs->{_prefetch_selector_range} = [ $sel_end + 1, $sel_end + @prefetch ];
3442 push @{ $attrs->{select} }, (map { $_->[0] } @prefetch);
3443 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
3445 push( @{$attrs->{order_by}}, @$prefetch_ordering );
3446 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
3450 # if both page and offset are specified, produce a combined offset
3451 # even though it doesn't make much sense, this is what pre 081xx has
3453 if (my $page = delete $attrs->{page}) {
3455 ($attrs->{rows} * ($page - 1))
3457 ($attrs->{offset} || 0)
3461 return $self->{_attrs} = $attrs;
3465 my ($self, $attr) = @_;
3467 if (ref $attr eq 'HASH') {
3468 return $self->_rollout_hash($attr);
3469 } elsif (ref $attr eq 'ARRAY') {
3470 return $self->_rollout_array($attr);
3476 sub _rollout_array {
3477 my ($self, $attr) = @_;
3480 foreach my $element (@{$attr}) {
3481 if (ref $element eq 'HASH') {
3482 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3483 } elsif (ref $element eq 'ARRAY') {
3484 # XXX - should probably recurse here
3485 push( @rolled_array, @{$self->_rollout_array($element)} );
3487 push( @rolled_array, $element );
3490 return \@rolled_array;
3494 my ($self, $attr) = @_;
3497 foreach my $key (keys %{$attr}) {
3498 push( @rolled_array, { $key => $attr->{$key} } );
3500 return \@rolled_array;
3503 sub _calculate_score {
3504 my ($self, $a, $b) = @_;
3506 if (defined $a xor defined $b) {
3509 elsif (not defined $a) {
3513 if (ref $b eq 'HASH') {
3514 my ($b_key) = keys %{$b};
3515 if (ref $a eq 'HASH') {
3516 my ($a_key) = keys %{$a};
3517 if ($a_key eq $b_key) {
3518 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3523 return ($a eq $b_key) ? 1 : 0;
3526 if (ref $a eq 'HASH') {
3527 my ($a_key) = keys %{$a};
3528 return ($b eq $a_key) ? 1 : 0;
3530 return ($b eq $a) ? 1 : 0;
3535 sub _merge_joinpref_attr {
3536 my ($self, $orig, $import) = @_;
3538 return $import unless defined($orig);
3539 return $orig unless defined($import);
3541 $orig = $self->_rollout_attr($orig);
3542 $import = $self->_rollout_attr($import);
3545 foreach my $import_element ( @{$import} ) {
3546 # find best candidate from $orig to merge $b_element into
3547 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3548 foreach my $orig_element ( @{$orig} ) {
3549 my $score = $self->_calculate_score( $orig_element, $import_element );
3550 if ($score > $best_candidate->{score}) {
3551 $best_candidate->{position} = $position;
3552 $best_candidate->{score} = $score;
3556 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3557 $import_key = '' if not defined $import_key;
3559 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3560 push( @{$orig}, $import_element );
3562 my $orig_best = $orig->[$best_candidate->{position}];
3563 # merge orig_best and b_element together and replace original with merged
3564 if (ref $orig_best ne 'HASH') {
3565 $orig->[$best_candidate->{position}] = $import_element;
3566 } elsif (ref $import_element eq 'HASH') {
3567 my ($key) = keys %{$orig_best};
3568 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3571 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3582 require Hash::Merge;
3583 my $hm = Hash::Merge->new;
3585 $hm->specify_behavior({
3588 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3590 if ($defl xor $defr) {
3591 return [ $defl ? $_[0] : $_[1] ];
3596 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3600 return [$_[0], $_[1]];
3604 return $_[1] if !defined $_[0];
3605 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3606 return [$_[0], @{$_[1]}]
3609 return [] if !defined $_[0] and !keys %{$_[1]};
3610 return [ $_[1] ] if !defined $_[0];
3611 return [ $_[0] ] if !keys %{$_[1]};
3612 return [$_[0], $_[1]]
3617 return $_[0] if !defined $_[1];
3618 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3619 return [@{$_[0]}, $_[1]]
3622 my @ret = @{$_[0]} or return $_[1];
3623 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3624 my %idx = map { $_ => 1 } @ret;
3625 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3629 return [ $_[1] ] if ! @{$_[0]};
3630 return $_[0] if !keys %{$_[1]};
3631 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3632 return [ @{$_[0]}, $_[1] ];
3637 return [] if !keys %{$_[0]} and !defined $_[1];
3638 return [ $_[0] ] if !defined $_[1];
3639 return [ $_[1] ] if !keys %{$_[0]};
3640 return [$_[0], $_[1]]
3643 return [] if !keys %{$_[0]} and !@{$_[1]};
3644 return [ $_[0] ] if !@{$_[1]};
3645 return $_[1] if !keys %{$_[0]};
3646 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3647 return [ $_[0], @{$_[1]} ];
3650 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3651 return [ $_[0] ] if !keys %{$_[1]};
3652 return [ $_[1] ] if !keys %{$_[0]};
3653 return [ $_[0] ] if $_[0] eq $_[1];
3654 return [ $_[0], $_[1] ];
3657 } => 'DBIC_RS_ATTR_MERGER');
3661 return $hm->merge ($_[1], $_[2]);
3665 sub STORABLE_freeze {
3666 my ($self, $cloning) = @_;
3667 my $to_serialize = { %$self };
3669 # A cursor in progress can't be serialized (and would make little sense anyway)
3670 delete $to_serialize->{cursor};
3672 # nor is it sensical to store a not-yet-fired-count pager
3673 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3674 delete $to_serialize->{pager};
3677 Storable::nfreeze($to_serialize);
3680 # need this hook for symmetry
3682 my ($self, $cloning, $serialized) = @_;
3684 %$self = %{ Storable::thaw($serialized) };
3690 =head2 throw_exception
3692 See L<DBIx::Class::Schema/throw_exception> for details.
3696 sub throw_exception {
3699 if (ref $self and my $rsrc = $self->result_source) {
3700 $rsrc->throw_exception(@_)
3703 DBIx::Class::Exception->throw(@_);
3707 # XXX: FIXME: Attributes docs need clearing up
3711 Attributes are used to refine a ResultSet in various ways when
3712 searching for data. They can be passed to any method which takes an
3713 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3716 These are in no particular order:
3722 =item Value: ( $order_by | \@order_by | \%order_by )
3726 Which column(s) to order the results by.
3728 [The full list of suitable values is documented in
3729 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3732 If a single column name, or an arrayref of names is supplied, the
3733 argument is passed through directly to SQL. The hashref syntax allows
3734 for connection-agnostic specification of ordering direction:
3736 For descending order:
3738 order_by => { -desc => [qw/col1 col2 col3/] }
3740 For explicit ascending order:
3742 order_by => { -asc => 'col' }
3744 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3745 supported, although you are strongly encouraged to use the hashref
3746 syntax as outlined above.
3752 =item Value: \@columns
3756 Shortcut to request a particular set of columns to be retrieved. Each
3757 column spec may be a string (a table column name), or a hash (in which
3758 case the key is the C<as> value, and the value is used as the C<select>
3759 expression). Adds C<me.> onto the start of any column without a C<.> in
3760 it and sets C<select> from that, then auto-populates C<as> from
3761 C<select> as normal. (You may also use the C<cols> attribute, as in
3762 earlier versions of DBIC.)
3764 Essentially C<columns> does the same as L</select> and L</as>.
3766 columns => [ 'foo', { bar => 'baz' } ]
3770 select => [qw/foo baz/],
3777 =item Value: \@columns
3781 Indicates additional columns to be selected from storage. Works the same
3782 as L</columns> but adds columns to the selection. (You may also use the
3783 C<include_columns> attribute, as in earlier versions of DBIC). For
3786 $schema->resultset('CD')->search(undef, {
3787 '+columns' => ['artist.name'],
3791 would return all CDs and include a 'name' column to the information
3792 passed to object inflation. Note that the 'artist' is the name of the
3793 column (or relationship) accessor, and 'name' is the name of the column
3794 accessor in the related table.
3796 B<NOTE:> You need to explicitly quote '+columns' when defining the attribute.
3797 Not doing so causes Perl to incorrectly interpret +columns as a bareword with a
3798 unary plus operator before it.
3800 =head2 include_columns
3804 =item Value: \@columns
3808 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3814 =item Value: \@select_columns
3818 Indicates which columns should be selected from the storage. You can use
3819 column names, or in the case of RDBMS back ends, function or stored procedure
3822 $rs = $schema->resultset('Employee')->search(undef, {
3825 { count => 'employeeid' },
3826 { max => { length => 'name' }, -as => 'longest_name' }
3831 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
3833 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
3834 use L</select>, to instruct DBIx::Class how to store the result of the column.
3835 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
3836 identifier aliasing. You can however alias a function, so you can use it in
3837 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
3838 attribute> supplied as shown in the example above.
3840 B<NOTE:> You need to explicitly quote '+select'/'+as' when defining the attributes.
3841 Not doing so causes Perl to incorrectly interpret them as a bareword with a
3842 unary plus operator before it.
3848 Indicates additional columns to be selected from storage. Works the same as
3849 L</select> but adds columns to the default selection, instead of specifying
3858 Indicates additional column names for those added via L</+select>. See L</as>.
3866 =item Value: \@inflation_names
3870 Indicates column names for object inflation. That is L</as> indicates the
3871 slot name in which the column value will be stored within the
3872 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
3873 identifier by the C<get_column> method (or via the object accessor B<if one
3874 with the same name already exists>) as shown below. The L</as> attribute has
3875 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
3877 $rs = $schema->resultset('Employee')->search(undef, {
3880 { count => 'employeeid' },
3881 { max => { length => 'name' }, -as => 'longest_name' }
3890 If the object against which the search is performed already has an accessor
3891 matching a column name specified in C<as>, the value can be retrieved using
3892 the accessor as normal:
3894 my $name = $employee->name();
3896 If on the other hand an accessor does not exist in the object, you need to
3897 use C<get_column> instead:
3899 my $employee_count = $employee->get_column('employee_count');
3901 You can create your own accessors if required - see
3902 L<DBIx::Class::Manual::Cookbook> for details.
3908 =item Value: ($rel_name | \@rel_names | \%rel_names)
3912 Contains a list of relationships that should be joined for this query. For
3915 # Get CDs by Nine Inch Nails
3916 my $rs = $schema->resultset('CD')->search(
3917 { 'artist.name' => 'Nine Inch Nails' },
3918 { join => 'artist' }
3921 Can also contain a hash reference to refer to the other relation's relations.
3924 package MyApp::Schema::Track;
3925 use base qw/DBIx::Class/;
3926 __PACKAGE__->table('track');
3927 __PACKAGE__->add_columns(qw/trackid cd position title/);
3928 __PACKAGE__->set_primary_key('trackid');
3929 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3932 # In your application
3933 my $rs = $schema->resultset('Artist')->search(
3934 { 'track.title' => 'Teardrop' },
3936 join => { cd => 'track' },
3937 order_by => 'artist.name',
3941 You need to use the relationship (not the table) name in conditions,
3942 because they are aliased as such. The current table is aliased as "me", so
3943 you need to use me.column_name in order to avoid ambiguity. For example:
3945 # Get CDs from 1984 with a 'Foo' track
3946 my $rs = $schema->resultset('CD')->search(
3949 'tracks.name' => 'Foo'
3951 { join => 'tracks' }
3954 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3955 similarly for a third time). For e.g.
3957 my $rs = $schema->resultset('Artist')->search({
3958 'cds.title' => 'Down to Earth',
3959 'cds_2.title' => 'Popular',
3961 join => [ qw/cds cds/ ],
3964 will return a set of all artists that have both a cd with title 'Down
3965 to Earth' and a cd with title 'Popular'.
3967 If you want to fetch related objects from other tables as well, see C<prefetch>
3970 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3976 =item Value: ($rel_name | \@rel_names | \%rel_names)
3980 Contains one or more relationships that should be fetched along with
3981 the main query (when they are accessed afterwards the data will
3982 already be available, without extra queries to the database). This is
3983 useful for when you know you will need the related objects, because it
3984 saves at least one query:
3986 my $rs = $schema->resultset('Tag')->search(
3995 The initial search results in SQL like the following:
3997 SELECT tag.*, cd.*, artist.* FROM tag
3998 JOIN cd ON tag.cd = cd.cdid
3999 JOIN artist ON cd.artist = artist.artistid
4001 L<DBIx::Class> has no need to go back to the database when we access the
4002 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4005 Simple prefetches will be joined automatically, so there is no need
4006 for a C<join> attribute in the above search.
4008 L</prefetch> can be used with the any of the relationship types and
4009 multiple prefetches can be specified together. Below is a more complex
4010 example that prefetches a CD's artist, its liner notes (if present),
4011 the cover image, the tracks on that cd, and the guests on those
4015 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4016 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4017 My::Schema::CD->has_one( cover_image => 'My::Schema::Artwork' );
4018 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4020 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4022 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4025 my $rs = $schema->resultset('CD')->search(
4029 { artist => 'record_label'}, # belongs_to => belongs_to
4030 'liner_note', # might_have
4031 'cover_image', # has_one
4032 { tracks => 'guests' }, # has_many => has_many
4037 This will produce SQL like the following:
4039 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4043 ON artist.artistid = me.artistid
4044 JOIN record_label record_label
4045 ON record_label.labelid = artist.labelid
4046 LEFT JOIN track tracks
4047 ON tracks.cdid = me.cdid
4048 LEFT JOIN guest guests
4049 ON guests.trackid = track.trackid
4050 LEFT JOIN liner_notes liner_note
4051 ON liner_note.cdid = me.cdid
4052 JOIN cd_artwork cover_image
4053 ON cover_image.cdid = me.cdid
4056 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4057 C<tracks>, and C<guests> of the CD will all be available through the
4058 relationship accessors without the need for additional queries to the
4061 However, there is one caveat to be observed: it can be dangerous to
4062 prefetch more than one L<has_many|DBIx::Class::Relationship/has_many>
4063 relationship on a given level. e.g.:
4065 my $rs = $schema->resultset('CD')->search(
4069 'tracks', # has_many
4070 { cd_to_producer => 'producer' }, # has_many => belongs_to (i.e. m2m)
4075 In fact, C<DBIx::Class> will emit the following warning:
4077 Prefetching multiple has_many rels tracks and cd_to_producer at top
4078 level will explode the number of row objects retrievable via ->next
4079 or ->all. Use at your own risk.
4081 The collapser currently can't identify duplicate tuples for multiple
4082 L<has_many|DBIx::Class::Relationship/has_many> relationships and as a
4083 result the second L<has_many|DBIx::Class::Relationship/has_many>
4084 relation could contain redundant objects.
4086 =head3 Using L</prefetch> with L</join>
4088 L</prefetch> implies a L</join> with the equivalent argument, and is
4089 properly merged with any existing L</join> specification. So the
4092 my $rs = $schema->resultset('CD')->search(
4093 {'record_label.name' => 'Music Product Ltd.'},
4095 join => {artist => 'record_label'},
4096 prefetch => 'artist',
4100 ... will work, searching on the record label's name, but only
4101 prefetching the C<artist>.
4103 =head3 Using L</prefetch> with L</select> / L</+select> / L</as> / L</+as>
4105 L</prefetch> implies a L</+select>/L</+as> with the fields of the
4106 prefetched relations. So given:
4108 my $rs = $schema->resultset('CD')->search(
4111 select => ['cd.title'],
4113 prefetch => 'artist',
4117 The L</select> becomes: C<'cd.title', 'artist.*'> and the L</as>
4118 becomes: C<'cd_title', 'artist.*'>.
4122 Prefetch does a lot of deep magic. As such, it may not behave exactly
4123 as you might expect.
4129 Prefetch uses the L</cache> to populate the prefetched relationships. This
4130 may or may not be what you want.
4134 If you specify a condition on a prefetched relationship, ONLY those
4135 rows that match the prefetched condition will be fetched into that relationship.
4136 This means that adding prefetch to a search() B<may alter> what is returned by
4137 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4139 my $artist_rs = $schema->resultset('Artist')->search({
4145 my $count = $artist_rs->first->cds->count;
4147 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4149 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4151 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4153 that cmp_ok() may or may not pass depending on the datasets involved. This
4154 behavior may or may not survive the 0.09 transition.
4166 Makes the resultset paged and specifies the page to retrieve. Effectively
4167 identical to creating a non-pages resultset and then calling ->page($page)
4170 If L</rows> attribute is not specified it defaults to 10 rows per page.
4172 When you have a paged resultset, L</count> will only return the number
4173 of rows in the page. To get the total, use the L</pager> and call
4174 C<total_entries> on it.
4184 Specifies the maximum number of rows for direct retrieval or the number of
4185 rows per page if the page attribute or method is used.
4191 =item Value: $offset
4195 Specifies the (zero-based) row number for the first row to be returned, or the
4196 of the first row of the first page if paging is used.
4202 =item Value: \@columns
4206 A arrayref of columns to group by. Can include columns of joined tables.
4208 group_by => [qw/ column1 column2 ... /]
4214 =item Value: $condition
4218 HAVING is a select statement attribute that is applied between GROUP BY and
4219 ORDER BY. It is applied to the after the grouping calculations have been
4222 having => { 'count_employee' => { '>=', 100 } }
4224 or with an in-place function in which case literal SQL is required:
4226 having => \[ 'count(employee) >= ?', [ count => 100 ] ]
4232 =item Value: (0 | 1)
4236 Set to 1 to group by all columns. If the resultset already has a group_by
4237 attribute, this setting is ignored and an appropriate warning is issued.
4243 Adds to the WHERE clause.
4245 # only return rows WHERE deleted IS NULL for all searches
4246 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
4248 Can be overridden by passing C<< { where => undef } >> as an attribute
4251 For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
4257 Set to 1 to cache search results. This prevents extra SQL queries if you
4258 revisit rows in your ResultSet:
4260 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4262 while( my $artist = $resultset->next ) {
4266 $rs->first; # without cache, this would issue a query
4268 By default, searches are not cached.
4270 For more examples of using these attributes, see
4271 L<DBIx::Class::Manual::Cookbook>.
4277 =item Value: ( 'update' | 'shared' )
4281 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT