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 ($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 $self->throw_exception(
1042 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
1043 ) if $attrs->{collapse};
1046 if (defined $attrs->{where}) {
1049 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1050 $where, delete $attrs->{where} ]
1053 $attrs->{where} = $where;
1057 my $data = [ $self->result_source->storage->select_single(
1058 $attrs->{from}, $attrs->{select},
1059 $attrs->{where}, $attrs
1061 return undef unless @$data;
1062 $self->{stashed_rows} = [ $data ];
1063 $self->_construct_objects->[0];
1069 # Recursively collapse the query, accumulating values for each column.
1071 sub _collapse_query {
1072 my ($self, $query, $collapsed) = @_;
1076 if (ref $query eq 'ARRAY') {
1077 foreach my $subquery (@$query) {
1078 next unless ref $subquery; # -or
1079 $collapsed = $self->_collapse_query($subquery, $collapsed);
1082 elsif (ref $query eq 'HASH') {
1083 if (keys %$query and (keys %$query)[0] eq '-and') {
1084 foreach my $subquery (@{$query->{-and}}) {
1085 $collapsed = $self->_collapse_query($subquery, $collapsed);
1089 foreach my $col (keys %$query) {
1090 my $value = $query->{$col};
1091 $collapsed->{$col}{$value}++;
1103 =item Arguments: $cond?
1105 =item Return Value: $resultsetcolumn
1109 my $max_length = $rs->get_column('length')->max;
1111 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1116 my ($self, $column) = @_;
1117 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
1125 =item Arguments: $cond, \%attrs?
1127 =item Return Value: $resultset (scalar context) || @row_objs (list context)
1131 # WHERE title LIKE '%blue%'
1132 $cd_rs = $rs->search_like({ title => '%blue%'});
1134 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1135 that this is simply a convenience method retained for ex Class::DBI users.
1136 You most likely want to use L</search> with specific operators.
1138 For more information, see L<DBIx::Class::Manual::Cookbook>.
1140 This method is deprecated and will be removed in 0.09. Use L</search()>
1141 instead. An example conversion is:
1143 ->search_like({ foo => 'bar' });
1147 ->search({ foo => { like => 'bar' } });
1154 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1155 .' Instead use ->search({ x => { -like => "y%" } })'
1156 .' (note the outer pair of {}s - they are important!)'
1158 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1159 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1160 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1161 return $class->search($query, { %$attrs });
1168 =item Arguments: $first, $last
1170 =item Return Value: $resultset (scalar context) || @row_objs (list context)
1174 Returns a resultset or object list representing a subset of elements from the
1175 resultset slice is called on. Indexes are from 0, i.e., to get the first
1176 three records, call:
1178 my ($one, $two, $three) = $rs->slice(0, 2);
1183 my ($self, $min, $max) = @_;
1184 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1185 $attrs->{offset} = $self->{attrs}{offset} || 0;
1186 $attrs->{offset} += $min;
1187 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1188 return $self->search(undef, $attrs);
1189 #my $slice = (ref $self)->new($self->result_source, $attrs);
1190 #return (wantarray ? $slice->all : $slice);
1197 =item Arguments: none
1199 =item Return Value: $result | undef
1203 Returns the next element in the resultset (C<undef> is there is none).
1205 Can be used to efficiently iterate over records in the resultset:
1207 my $rs = $schema->resultset('CD')->search;
1208 while (my $cd = $rs->next) {
1212 Note that you need to store the resultset object, and call C<next> on it.
1213 Calling C<< resultset('Table')->next >> repeatedly will always return the
1214 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}++];
1226 if ($self->{attrs}{cache}) {
1227 delete $self->{pager};
1228 $self->{all_cache_position} = 1;
1229 return ($self->all)[0];
1232 return shift(@{$self->{stashed_objects}}) if @{ $self->{stashed_objects}||[] };
1234 $self->{stashed_objects} = $self->_construct_objects
1237 return shift @{$self->{stashed_objects}};
1240 # Constructs as many objects as it can in one pass while respecting
1241 # cursor laziness. Several modes of operation:
1243 # * Always builds everything present in @{$self->{stashed_rows}}
1244 # * If called with $fetch_all true - pulls everything off the cursor and
1245 # builds all objects in one pass
1246 # * If $self->_resolved_attrs->{collapse} is true, checks the order_by
1247 # and if the resultset is ordered properly by the left side:
1248 # * Fetches stuff off the cursor until the "master object" changes,
1249 # and saves the last extra row (if any) in @{$self->{stashed_rows}}
1251 # * Just fetches, and collapses/constructs everything as if $fetch_all
1252 # was requested (there is no other way to collapse except for an
1254 # * If no collapse is requested - just get the next row, construct and
1256 sub _construct_objects {
1257 my ($self, $fetch_all) = @_;
1259 my $rsrc = $self->result_source;
1260 my $attrs = $self->_resolved_attrs;
1261 my $cursor = $self->cursor;
1263 # this will be used as both initial raw-row collector AND as a RV of
1264 # _construct_objects. Not regrowing the array twice matters a lot...
1265 # a suprising amount actually
1266 my $rows = (delete $self->{stashed_rows}) || [];
1268 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1269 $rows = [ @$rows, $cursor->all ];
1271 elsif (!$attrs->{collapse}) {
1272 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1273 push @$rows, do { my @r = $cursor->next; @r ? \@r : () }
1277 $attrs->{_ordered_for_collapse} ||= (!$attrs->{order_by}) ? undef : do {
1278 my $st = $rsrc->schema->storage;
1281 ( $st->_extract_order_criteria($attrs->{order_by}) )
1284 my $colinfos = $st->_resolve_column_info($attrs->{from}, \@ord_cols);
1286 for (0 .. $#ord_cols) {
1288 ! $colinfos->{$ord_cols[$_]}
1290 $colinfos->{$ord_cols[$_]}{-result_source} != $rsrc
1292 splice @ord_cols, $_;
1297 # since all we check here are the start of the order_by belonging to the
1298 # top level $rsrc, a present identifying set will mean that the resultset
1299 # is ordered by its leftmost table in a tsable manner
1300 (@ord_cols and $rsrc->_identifying_column_set({ map
1301 { $colinfos->{$_}{-colname} => $colinfos->{$_} }
1306 if ($attrs->{_ordered_for_collapse}) {
1307 push @$rows, do { my @r = $cursor->next; @r ? \@r : () };
1309 # instead of looping over ->next, use ->all in stealth mode
1310 # FIXME - encapsulation breach, got to be a better way
1311 elsif (! $cursor->{done}) {
1312 push @$rows, $cursor->all;
1313 $cursor->{done} = 1;
1318 return undef unless @$rows;
1320 my $res_class = $self->result_class;
1321 my $inflator = $res_class->can ('inflate_result')
1322 or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
1324 my $infmap = $attrs->{as};
1326 if (!$attrs->{collapse} and $attrs->{_single_object_inflation}) {
1327 # construct a much simpler array->hash folder for the one-table cases right here
1329 # FIXME SUBOPTIMAL this is a very very very hot spot
1330 # while rather optimal we can *still* do much better, by
1331 # building a smarter [Row|HRI]::inflate_result(), and
1332 # switch to feeding it data via a much leaner interface
1334 # crude unscientific benchmarking indicated the shortcut eval is not worth it for
1335 # this particular resultset size
1337 my @as_idx = 0..$#$infmap;
1338 for my $r (@$rows) {
1339 $r = $inflator->($res_class, $rsrc, { map { $infmap->[$_] => $r->[$_] } @as_idx } );
1344 '$_ = $inflator->($res_class, $rsrc, { %s }) for @$rows',
1345 join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap )
1350 ($self->{_row_parser} ||= eval sprintf 'sub { %s }', $rsrc->_mk_row_parser({
1351 inflate_map => $infmap,
1352 selection => $attrs->{select},
1353 collapse => $attrs->{collapse},
1354 }) or die $@)->($rows, $fetch_all ? () : (
1355 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1356 sub { my @r = $cursor->next or return; \@r }, # how the collapser gets more rows
1357 ($self->{stashed_rows} = []), # where does it stuff excess
1358 )); # modify $rows in-place, shrinking/extending as necessary
1360 $_ = $inflator->($res_class, $rsrc, @$_) for @$rows;
1365 if ($attrs->{record_filter}) {
1366 $_ = $attrs->{record_filter}->($_) for @$rows;
1372 =head2 result_source
1376 =item Arguments: $result_source?
1378 =item Return Value: $result_source
1382 An accessor for the primary ResultSource object from which this ResultSet
1389 =item Arguments: $result_class?
1391 =item Return Value: $result_class
1395 An accessor for the class to use when creating row objects. Defaults to
1396 C<< result_source->result_class >> - which in most cases is the name of the
1397 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1399 Note that changing the result_class will also remove any components
1400 that were originally loaded in the source class via
1401 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1402 in the original source class will not run.
1407 my ($self, $result_class) = @_;
1408 if ($result_class) {
1409 unless (ref $result_class) { # don't fire this for an object
1410 $self->ensure_class_loaded($result_class);
1412 $self->_result_class($result_class);
1413 # THIS LINE WOULD BE A BUG - this accessor specifically exists to
1414 # permit the user to set result class on one result set only; it only
1415 # chains if provided to search()
1416 #$self->{attrs}{result_class} = $result_class if ref $self;
1418 $self->_result_class;
1425 =item Arguments: $cond, \%attrs??
1427 =item Return Value: $count
1431 Performs an SQL C<COUNT> with the same query as the resultset was built
1432 with to find the number of elements. Passing arguments is equivalent to
1433 C<< $rs->search ($cond, \%attrs)->count >>
1439 return $self->search(@_)->count if @_ and defined $_[0];
1440 return scalar @{ $self->get_cache } if $self->get_cache;
1442 my $attrs = $self->_resolved_attrs_copy;
1444 # this is a little optimization - it is faster to do the limit
1445 # adjustments in software, instead of a subquery
1446 my $rows = delete $attrs->{rows};
1447 my $offset = delete $attrs->{offset};
1450 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1451 $crs = $self->_count_subq_rs ($attrs);
1454 $crs = $self->_count_rs ($attrs);
1456 my $count = $crs->next;
1458 $count -= $offset if $offset;
1459 $count = $rows if $rows and $rows < $count;
1460 $count = 0 if ($count < 0);
1469 =item Arguments: $cond, \%attrs??
1471 =item Return Value: $count_rs
1475 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1476 This can be very handy for subqueries:
1478 ->search( { amount => $some_rs->count_rs->as_query } )
1480 As with regular resultsets the SQL query will be executed only after
1481 the resultset is accessed via L</next> or L</all>. That would return
1482 the same single value obtainable via L</count>.
1488 return $self->search(@_)->count_rs if @_;
1490 # this may look like a lack of abstraction (count() does about the same)
1491 # but in fact an _rs *must* use a subquery for the limits, as the
1492 # software based limiting can not be ported if this $rs is to be used
1493 # in a subquery itself (i.e. ->as_query)
1494 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1495 return $self->_count_subq_rs;
1498 return $self->_count_rs;
1503 # returns a ResultSetColumn object tied to the count query
1506 my ($self, $attrs) = @_;
1508 my $rsrc = $self->result_source;
1509 $attrs ||= $self->_resolved_attrs;
1511 my $tmp_attrs = { %$attrs };
1512 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1513 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1515 # overwrite the selector (supplied by the storage)
1516 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $attrs);
1517 $tmp_attrs->{as} = 'count';
1518 delete @{$tmp_attrs}{qw/columns/};
1520 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1526 # same as above but uses a subquery
1528 sub _count_subq_rs {
1529 my ($self, $attrs) = @_;
1531 my $rsrc = $self->result_source;
1532 $attrs ||= $self->_resolved_attrs;
1534 my $sub_attrs = { %$attrs };
1535 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1536 delete @{$sub_attrs}{qw/collapse columns as select _prefetch_selector_range order_by for/};
1538 # if we multi-prefetch we group_by something unique, as this is what we would
1539 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1540 if ( $attrs->{collapse} ) {
1541 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1542 $rsrc->_identifying_column_set || $self->throw_exception(
1543 'Unable to construct a unique group_by criteria properly collapsing the '
1544 . 'has_many prefetch before count()'
1549 # Calculate subquery selector
1550 if (my $g = $sub_attrs->{group_by}) {
1552 my $sql_maker = $rsrc->storage->sql_maker;
1554 # necessary as the group_by may refer to aliased functions
1556 for my $sel (@{$attrs->{select}}) {
1557 $sel_index->{$sel->{-as}} = $sel
1558 if (ref $sel eq 'HASH' and $sel->{-as});
1561 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1562 # also look for named aggregates referred in the having clause
1563 # having often contains scalarrefs - thus parse it out entirely
1565 if ($attrs->{having}) {
1566 local $sql_maker->{having_bind};
1567 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1568 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1569 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1570 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1571 # if we don't unset it we screw up retarded but unfortunately working
1572 # 'MAX(foo.bar)' => { '>', 3 }
1573 $sql_maker->{name_sep} = '';
1576 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1578 my $sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1580 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1581 # and if all fails for an utterly naive quoted scalar-with-function
1583 $rquote $sep $lquote (.+?) $rquote
1585 [\s,] \w+ \. (\w+) [\s,]
1587 [\s,] $lquote (.+?) $rquote [\s,]
1589 push @parts, ($1 || $2 || $3); # one of them matched if we got here
1594 my $colpiece = $sel_index->{$_} || $_;
1596 # unqualify join-based group_by's. Arcane but possible query
1597 # also horrible horrible hack to alias a column (not a func.)
1598 # (probably need to introduce SQLA syntax)
1599 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1602 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1604 push @{$sub_attrs->{select}}, $colpiece;
1608 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1609 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1612 return $rsrc->resultset_class
1613 ->new ($rsrc, $sub_attrs)
1615 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1616 ->get_column ('count');
1623 =head2 count_literal
1627 =item Arguments: $sql_fragment, @bind_values
1629 =item Return Value: $count
1633 Counts the results in a literal query. Equivalent to calling L</search_literal>
1634 with the passed arguments, then L</count>.
1638 sub count_literal { shift->search_literal(@_)->count; }
1644 =item Arguments: none
1646 =item Return Value: @objects
1650 Returns all elements in the resultset.
1657 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1660 delete $self->{stashed_rows};
1661 delete $self->{stashed_objects};
1663 if (my $c = $self->get_cache) {
1667 $self->cursor->reset;
1669 my $objs = $self->_construct_objects('fetch_all') || [];
1671 $self->set_cache($objs) if $self->{attrs}{cache};
1680 =item Arguments: none
1682 =item Return Value: $self
1686 Resets the resultset's cursor, so you can iterate through the elements again.
1687 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1694 delete $self->{_attrs};
1695 delete $self->{stashed_rows};
1696 delete $self->{stashed_objects};
1698 $self->{all_cache_position} = 0;
1699 $self->cursor->reset;
1707 =item Arguments: none
1709 =item Return Value: $object | undef
1713 Resets the resultset and returns an object for the first result (or C<undef>
1714 if the resultset is empty).
1719 return $_[0]->reset->next;
1725 # Determines whether and what type of subquery is required for the $rs operation.
1726 # If grouping is necessary either supplies its own, or verifies the current one
1727 # After all is done delegates to the proper storage method.
1729 sub _rs_update_delete {
1730 my ($self, $op, $values) = @_;
1732 my $cond = $self->{cond};
1733 my $rsrc = $self->result_source;
1734 my $storage = $rsrc->schema->storage;
1736 my $attrs = { %{$self->_resolved_attrs} };
1738 # "needs" is a strong word here - if the subquery is part of an IN clause - no point of
1739 # even adding the group_by. It will really be used only when composing a poor-man's
1740 # multicolumn-IN equivalent OR set
1741 my $needs_group_by_subq = defined $attrs->{group_by};
1743 # simplify the joinmap and maybe decide if a grouping (and thus subquery) is necessary
1744 my $relation_classifications;
1745 if (ref($attrs->{from}) eq 'ARRAY') {
1746 $attrs->{from} = $storage->_prune_unused_joins ($attrs->{from}, $attrs->{select}, $cond, $attrs);
1748 $relation_classifications = $storage->_resolve_aliastypes_from_select_args (
1749 [ @{$attrs->{from}}[1 .. $#{$attrs->{from}}] ],
1753 ) unless $needs_group_by_subq; # we already know we need a group, no point of resolving them
1756 $needs_group_by_subq ||= 1; # if {from} is unparseable assume the worst
1759 $needs_group_by_subq ||= exists $relation_classifications->{multiplying};
1761 # if no subquery - life is easy-ish
1763 $needs_group_by_subq
1765 keys %$relation_classifications # if any joins at all - need to wrap a subq
1767 $self->_has_resolved_attr(qw/rows offset/) # limits call for a subq
1769 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1770 # a condition containing 'me' or other table prefixes will not work
1771 # at all. What this code tries to do (badly) is to generate a condition
1772 # with the qualifiers removed, by exploiting the quote mechanism of sqla
1774 # this is atrocious and should be replaced by normal sqla introspection
1776 my ($sql, @bind) = do {
1777 my $sqla = $rsrc->storage->sql_maker;
1778 local $sqla->{_dequalify_idents} = 1;
1779 $sqla->_recurse_where($self->{cond});
1782 return $rsrc->storage->$op(
1784 $op eq 'update' ? $values : (),
1785 $self->{cond} ? \[$sql, @bind] : (),
1789 # we got this far - means it is time to wrap a subquery
1790 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1792 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1797 my $existing_group_by = delete $attrs->{group_by};
1799 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1800 delete $attrs->{$_} for qw/collapse select _prefetch_selector_range as/;
1801 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1802 $attrs->{group_by} = \ ''; # FIXME - this is an evil hack, it causes the optimiser to kick in and throw away the LEFT joins
1803 my $subrs = (ref $self)->new($rsrc, $attrs);
1805 if (@$idcols == 1) {
1806 return $storage->$op (
1808 $op eq 'update' ? $values : (),
1809 { $idcols->[0] => { -in => $subrs->as_query } },
1812 elsif ($storage->_use_multicolumn_in) {
1813 # This is hideously ugly, but SQLA does not understand multicol IN expressions
1814 my $sql_maker = $storage->sql_maker;
1815 my ($sql, @bind) = @${$subrs->as_query};
1816 $sql = sprintf ('(%s) IN %s', # the as_query already comes with a set of parenthesis
1817 join (', ', map { $sql_maker->_quote ($_) } @$idcols),
1821 return $storage->$op (
1823 $op eq 'update' ? $values : (),
1828 # if all else fails - get all primary keys and operate over a ORed set
1829 # wrap in a transaction for consistency
1830 # this is where the group_by starts to matter
1832 if ($needs_group_by_subq) {
1833 $subq_group_by = $attrs->{columns};
1835 # make sure if there is a supplied group_by it matches the columns compiled above
1836 # perfectly. Anything else can not be sanely executed on most databases so croak
1837 # right then and there
1838 if ($existing_group_by) {
1839 my @current_group_by = map
1840 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1845 join ("\x00", sort @current_group_by)
1847 join ("\x00", sort @$subq_group_by )
1849 $self->throw_exception (
1850 "You have just attempted a $op operation on a resultset which does group_by"
1851 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1852 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1853 . ' kind of queries. Please retry the operation with a modified group_by or'
1854 . ' without using one at all.'
1860 my $guard = $storage->txn_scope_guard;
1863 for my $row ($subrs->search({}, { group_by => $subq_group_by })->cursor->all) {
1864 push @op_condition, { map
1865 { $idcols->[$_] => $row->[$_] }
1870 my $res = $storage->$op (
1872 $op eq 'update' ? $values : (),
1886 =item Arguments: \%values
1888 =item Return Value: $storage_rv
1892 Sets the specified columns in the resultset to the supplied values in a
1893 single query. Note that this will not run any accessor/set_column/update
1894 triggers, nor will it update any row object instances derived from this
1895 resultset (this includes the contents of the L<resultset cache|/set_cache>
1896 if any). See L</update_all> if you need to execute any on-update
1897 triggers or cascades defined either by you or a
1898 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1900 The return value is a pass through of what the underlying
1901 storage backend returned, and may vary. See L<DBI/execute> for the most
1906 Note that L</update> does not process/deflate any of the values passed in.
1907 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
1908 ensure manually that any value passed to this method will stringify to
1909 something the RDBMS knows how to deal with. A notable example is the
1910 handling of L<DateTime> objects, for more info see:
1911 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
1916 my ($self, $values) = @_;
1917 $self->throw_exception('Values for update must be a hash')
1918 unless ref $values eq 'HASH';
1920 return $self->_rs_update_delete ('update', $values);
1927 =item Arguments: \%values
1929 =item Return Value: 1
1933 Fetches all objects and updates them one at a time via
1934 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
1935 triggers, while L</update> will not.
1940 my ($self, $values) = @_;
1941 $self->throw_exception('Values for update_all must be a hash')
1942 unless ref $values eq 'HASH';
1944 my $guard = $self->result_source->schema->txn_scope_guard;
1945 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
1954 =item Arguments: none
1956 =item Return Value: $storage_rv
1960 Deletes the rows matching this resultset in a single query. Note that this
1961 will not run any delete triggers, nor will it alter the
1962 L<in_storage|DBIx::Class::Row/in_storage> status of any row object instances
1963 derived from this resultset (this includes the contents of the
1964 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
1965 execute any on-delete triggers or cascades defined either by you or a
1966 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1968 The return value is a pass through of what the underlying storage backend
1969 returned, and may vary. See L<DBI/execute> for the most common case.
1975 $self->throw_exception('delete does not accept any arguments')
1978 return $self->_rs_update_delete ('delete');
1985 =item Arguments: none
1987 =item Return Value: 1
1991 Fetches all objects and deletes them one at a time via
1992 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
1993 triggers, while L</delete> will not.
1999 $self->throw_exception('delete_all does not accept any arguments')
2002 my $guard = $self->result_source->schema->txn_scope_guard;
2003 $_->delete for $self->all;
2012 =item Arguments: \@data;
2016 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
2017 For the arrayref of hashrefs style each hashref should be a structure suitable
2018 for submitting to a $resultset->create(...) method.
2020 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
2021 to insert the data, as this is a faster method.
2023 Otherwise, each set of data is inserted into the database using
2024 L<DBIx::Class::ResultSet/create>, and the resulting objects are
2025 accumulated into an array. The array itself, or an array reference
2026 is returned depending on scalar or list context.
2028 Example: Assuming an Artist Class that has many CDs Classes relating:
2030 my $Artist_rs = $schema->resultset("Artist");
2032 ## Void Context Example
2033 $Artist_rs->populate([
2034 { artistid => 4, name => 'Manufactured Crap', cds => [
2035 { title => 'My First CD', year => 2006 },
2036 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2039 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2040 { title => 'My parents sold me to a record company', year => 2005 },
2041 { title => 'Why Am I So Ugly?', year => 2006 },
2042 { title => 'I Got Surgery and am now Popular', year => 2007 }
2047 ## Array Context Example
2048 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
2049 { name => "Artist One"},
2050 { name => "Artist Two"},
2051 { name => "Artist Three", cds=> [
2052 { title => "First CD", year => 2007},
2053 { title => "Second CD", year => 2008},
2057 print $ArtistOne->name; ## response is 'Artist One'
2058 print $ArtistThree->cds->count ## reponse is '2'
2060 For the arrayref of arrayrefs style, the first element should be a list of the
2061 fieldsnames to which the remaining elements are rows being inserted. For
2064 $Arstist_rs->populate([
2065 [qw/artistid name/],
2066 [100, 'A Formally Unknown Singer'],
2067 [101, 'A singer that jumped the shark two albums ago'],
2068 [102, 'An actually cool singer'],
2071 Please note an important effect on your data when choosing between void and
2072 wantarray context. Since void context goes straight to C<insert_bulk> in
2073 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
2074 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
2075 create primary keys for you, you will find that your PKs are empty. In this
2076 case you will have to use the wantarray context in order to create those
2084 # cruft placed in standalone method
2085 my $data = $self->_normalize_populate_args(@_);
2087 return unless @$data;
2089 if(defined wantarray) {
2091 foreach my $item (@$data) {
2092 push(@created, $self->create($item));
2094 return wantarray ? @created : \@created;
2097 my $first = $data->[0];
2099 # if a column is a registered relationship, and is a non-blessed hash/array, consider
2100 # it relationship data
2101 my (@rels, @columns);
2102 my $rsrc = $self->result_source;
2103 my $rels = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2104 for (keys %$first) {
2105 my $ref = ref $first->{$_};
2106 $rels->{$_} && ($ref eq 'ARRAY' or $ref eq 'HASH')
2112 my @pks = $rsrc->primary_columns;
2114 ## do the belongs_to relationships
2115 foreach my $index (0..$#$data) {
2117 # delegate to create() for any dataset without primary keys with specified relationships
2118 if (grep { !defined $data->[$index]->{$_} } @pks ) {
2120 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
2121 my @ret = $self->populate($data);
2127 foreach my $rel (@rels) {
2128 next unless ref $data->[$index]->{$rel} eq "HASH";
2129 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
2130 my ($reverse_relname, $reverse_relinfo) = %{$rsrc->reverse_relationship_info($rel)};
2131 my $related = $result->result_source->_resolve_condition(
2132 $reverse_relinfo->{cond},
2138 delete $data->[$index]->{$rel};
2139 $data->[$index] = {%{$data->[$index]}, %$related};
2141 push @columns, keys %$related if $index == 0;
2145 ## inherit the data locked in the conditions of the resultset
2146 my ($rs_data) = $self->_merge_with_rscond({});
2147 delete @{$rs_data}{@columns};
2148 my @inherit_cols = keys %$rs_data;
2149 my @inherit_data = values %$rs_data;
2151 ## do bulk insert on current row
2152 $rsrc->storage->insert_bulk(
2154 [@columns, @inherit_cols],
2155 [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
2158 ## do the has_many relationships
2159 foreach my $item (@$data) {
2163 foreach my $rel (@rels) {
2164 next unless ref $item->{$rel} eq "ARRAY" && @{ $item->{$rel} };
2166 $main_row ||= $self->new_result({map { $_ => $item->{$_} } @pks});
2168 my $child = $main_row->$rel;
2170 my $related = $child->result_source->_resolve_condition(
2171 $rels->{$rel}{cond},
2177 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
2178 my @populate = map { {%$_, %$related} } @rows_to_add;
2180 $child->populate( \@populate );
2187 # populate() argumnets went over several incarnations
2188 # What we ultimately support is AoH
2189 sub _normalize_populate_args {
2190 my ($self, $arg) = @_;
2192 if (ref $arg eq 'ARRAY') {
2196 elsif (ref $arg->[0] eq 'HASH') {
2199 elsif (ref $arg->[0] eq 'ARRAY') {
2201 my @colnames = @{$arg->[0]};
2202 foreach my $values (@{$arg}[1 .. $#$arg]) {
2203 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
2209 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2216 =item Arguments: none
2218 =item Return Value: $pager
2222 Return Value a L<Data::Page> object for the current resultset. Only makes
2223 sense for queries with a C<page> attribute.
2225 To get the full count of entries for a paged resultset, call
2226 C<total_entries> on the L<Data::Page> object.
2233 return $self->{pager} if $self->{pager};
2235 my $attrs = $self->{attrs};
2236 if (!defined $attrs->{page}) {
2237 $self->throw_exception("Can't create pager for non-paged rs");
2239 elsif ($attrs->{page} <= 0) {
2240 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2242 $attrs->{rows} ||= 10;
2244 # throw away the paging flags and re-run the count (possibly
2245 # with a subselect) to get the real total count
2246 my $count_attrs = { %$attrs };
2247 delete $count_attrs->{$_} for qw/rows offset page pager/;
2249 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2251 require DBIx::Class::ResultSet::Pager;
2252 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2253 sub { $total_rs->count }, #lazy-get the total
2255 $self->{attrs}{page},
2263 =item Arguments: $page_number
2265 =item Return Value: $rs
2269 Returns a resultset for the $page_number page of the resultset on which page
2270 is called, where each page contains a number of rows equal to the 'rows'
2271 attribute set on the resultset (10 by default).
2276 my ($self, $page) = @_;
2277 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2284 =item Arguments: \%vals
2286 =item Return Value: $rowobject
2290 Creates a new row object in the resultset's result class and returns
2291 it. The row is not inserted into the database at this point, call
2292 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2293 will tell you whether the row object has been inserted or not.
2295 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2300 my ($self, $values) = @_;
2301 $self->throw_exception( "new_result needs a hash" )
2302 unless (ref $values eq 'HASH');
2304 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2308 @$cols_from_relations
2309 ? (-cols_from_relations => $cols_from_relations)
2311 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2314 return $self->result_class->new(\%new);
2317 # _merge_with_rscond
2319 # Takes a simple hash of K/V data and returns its copy merged with the
2320 # condition already present on the resultset. Additionally returns an
2321 # arrayref of value/condition names, which were inferred from related
2322 # objects (this is needed for in-memory related objects)
2323 sub _merge_with_rscond {
2324 my ($self, $data) = @_;
2326 my (%new_data, @cols_from_relations);
2328 my $alias = $self->{attrs}{alias};
2330 if (! defined $self->{cond}) {
2331 # just massage $data below
2333 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
2334 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
2335 @cols_from_relations = keys %new_data;
2337 elsif (ref $self->{cond} ne 'HASH') {
2338 $self->throw_exception(
2339 "Can't abstract implicit construct, resultset condition not a hash"
2343 # precendence must be given to passed values over values inherited from
2344 # the cond, so the order here is important.
2345 my $collapsed_cond = $self->_collapse_cond($self->{cond});
2346 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
2348 while ( my($col, $value) = each %implied ) {
2349 my $vref = ref $value;
2355 (keys %$value)[0] eq '='
2357 $new_data{$col} = $value->{'='};
2359 elsif( !$vref or $vref eq 'SCALAR' or blessed($value) ) {
2360 $new_data{$col} = $value;
2367 %{ $self->_remove_alias($data, $alias) },
2370 return (\%new_data, \@cols_from_relations);
2373 # _has_resolved_attr
2375 # determines if the resultset defines at least one
2376 # of the attributes supplied
2378 # used to determine if a subquery is neccessary
2380 # supports some virtual attributes:
2382 # This will scan for any joins being present on the resultset.
2383 # It is not a mere key-search but a deep inspection of {from}
2386 sub _has_resolved_attr {
2387 my ($self, @attr_names) = @_;
2389 my $attrs = $self->_resolved_attrs;
2393 for my $n (@attr_names) {
2394 if (grep { $n eq $_ } (qw/-join/) ) {
2395 $extra_checks{$n}++;
2399 my $attr = $attrs->{$n};
2401 next if not defined $attr;
2403 if (ref $attr eq 'HASH') {
2404 return 1 if keys %$attr;
2406 elsif (ref $attr eq 'ARRAY') {
2414 # a resolved join is expressed as a multi-level from
2416 $extra_checks{-join}
2418 ref $attrs->{from} eq 'ARRAY'
2420 @{$attrs->{from}} > 1
2428 # Recursively collapse the condition.
2430 sub _collapse_cond {
2431 my ($self, $cond, $collapsed) = @_;
2435 if (ref $cond eq 'ARRAY') {
2436 foreach my $subcond (@$cond) {
2437 next unless ref $subcond; # -or
2438 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2441 elsif (ref $cond eq 'HASH') {
2442 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2443 foreach my $subcond (@{$cond->{-and}}) {
2444 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2448 foreach my $col (keys %$cond) {
2449 my $value = $cond->{$col};
2450 $collapsed->{$col} = $value;
2460 # Remove the specified alias from the specified query hash. A copy is made so
2461 # the original query is not modified.
2464 my ($self, $query, $alias) = @_;
2466 my %orig = %{ $query || {} };
2469 foreach my $key (keys %orig) {
2471 $unaliased{$key} = $orig{$key};
2474 $unaliased{$1} = $orig{$key}
2475 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2485 =item Arguments: none
2487 =item Return Value: \[ $sql, @bind ]
2491 Returns the SQL query and bind vars associated with the invocant.
2493 This is generally used as the RHS for a subquery.
2500 my $attrs = $self->_resolved_attrs_copy;
2505 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2506 # $sql also has no wrapping parenthesis in list ctx
2508 my $sqlbind = $self->result_source->storage
2509 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2518 =item Arguments: \%vals, \%attrs?
2520 =item Return Value: $rowobject
2524 my $artist = $schema->resultset('Artist')->find_or_new(
2525 { artist => 'fred' }, { key => 'artists' });
2527 $cd->cd_to_producer->find_or_new({ producer => $producer },
2528 { key => 'primary });
2530 Find an existing record from this resultset using L</find>. if none exists,
2531 instantiate a new result object and return it. The object will not be saved
2532 into your storage until you call L<DBIx::Class::Row/insert> on it.
2534 You most likely want this method when looking for existing rows using a unique
2535 constraint that is not the primary key, or looking for related rows.
2537 If you want objects to be saved immediately, use L</find_or_create> instead.
2539 B<Note>: Make sure to read the documentation of L</find> and understand the
2540 significance of the C<key> attribute, as its lack may skew your search, and
2541 subsequently result in spurious new objects.
2543 B<Note>: Take care when using C<find_or_new> with a table having
2544 columns with default values that you intend to be automatically
2545 supplied by the database (e.g. an auto_increment primary key column).
2546 In normal usage, the value of such columns should NOT be included at
2547 all in the call to C<find_or_new>, even when set to C<undef>.
2553 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2554 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2555 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2558 return $self->new_result($hash);
2565 =item Arguments: \%vals
2567 =item Return Value: a L<DBIx::Class::Row> $object
2571 Attempt to create a single new row or a row with multiple related rows
2572 in the table represented by the resultset (and related tables). This
2573 will not check for duplicate rows before inserting, use
2574 L</find_or_create> to do that.
2576 To create one row for this resultset, pass a hashref of key/value
2577 pairs representing the columns of the table and the values you wish to
2578 store. If the appropriate relationships are set up, foreign key fields
2579 can also be passed an object representing the foreign row, and the
2580 value will be set to its primary key.
2582 To create related objects, pass a hashref of related-object column values
2583 B<keyed on the relationship name>. If the relationship is of type C<multi>
2584 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2585 The process will correctly identify columns holding foreign keys, and will
2586 transparently populate them from the keys of the corresponding relation.
2587 This can be applied recursively, and will work correctly for a structure
2588 with an arbitrary depth and width, as long as the relationships actually
2589 exists and the correct column data has been supplied.
2592 Instead of hashrefs of plain related data (key/value pairs), you may
2593 also pass new or inserted objects. New objects (not inserted yet, see
2594 L</new>), will be inserted into their appropriate tables.
2596 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2598 Example of creating a new row.
2600 $person_rs->create({
2601 name=>"Some Person",
2602 email=>"somebody@someplace.com"
2605 Example of creating a new row and also creating rows in a related C<has_many>
2606 or C<has_one> resultset. Note Arrayref.
2609 { artistid => 4, name => 'Manufactured Crap', cds => [
2610 { title => 'My First CD', year => 2006 },
2611 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2616 Example of creating a new row and also creating a row in a related
2617 C<belongs_to> resultset. Note Hashref.
2620 title=>"Music for Silly Walks",
2623 name=>"Silly Musician",
2631 When subclassing ResultSet never attempt to override this method. Since
2632 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2633 lot of the internals simply never call it, so your override will be
2634 bypassed more often than not. Override either L<new|DBIx::Class::Row/new>
2635 or L<insert|DBIx::Class::Row/insert> depending on how early in the
2636 L</create> process you need to intervene.
2643 my ($self, $attrs) = @_;
2644 $self->throw_exception( "create needs a hashref" )
2645 unless ref $attrs eq 'HASH';
2646 return $self->new_result($attrs)->insert;
2649 =head2 find_or_create
2653 =item Arguments: \%vals, \%attrs?
2655 =item Return Value: $rowobject
2659 $cd->cd_to_producer->find_or_create({ producer => $producer },
2660 { key => 'primary' });
2662 Tries to find a record based on its primary key or unique constraints; if none
2663 is found, creates one and returns that instead.
2665 my $cd = $schema->resultset('CD')->find_or_create({
2667 artist => 'Massive Attack',
2668 title => 'Mezzanine',
2672 Also takes an optional C<key> attribute, to search by a specific key or unique
2673 constraint. For example:
2675 my $cd = $schema->resultset('CD')->find_or_create(
2677 artist => 'Massive Attack',
2678 title => 'Mezzanine',
2680 { key => 'cd_artist_title' }
2683 B<Note>: Make sure to read the documentation of L</find> and understand the
2684 significance of the C<key> attribute, as its lack may skew your search, and
2685 subsequently result in spurious row creation.
2687 B<Note>: Because find_or_create() reads from the database and then
2688 possibly inserts based on the result, this method is subject to a race
2689 condition. Another process could create a record in the table after
2690 the find has completed and before the create has started. To avoid
2691 this problem, use find_or_create() inside a transaction.
2693 B<Note>: Take care when using C<find_or_create> with a table having
2694 columns with default values that you intend to be automatically
2695 supplied by the database (e.g. an auto_increment primary key column).
2696 In normal usage, the value of such columns should NOT be included at
2697 all in the call to C<find_or_create>, even when set to C<undef>.
2699 See also L</find> and L</update_or_create>. For information on how to declare
2700 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2702 If you need to know if an existing row was found or a new one created use
2703 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2704 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2707 my $cd = $schema->resultset('CD')->find_or_new({
2709 artist => 'Massive Attack',
2710 title => 'Mezzanine',
2714 if( $cd->in_storage ) {
2721 sub find_or_create {
2723 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2724 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2725 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2728 return $self->create($hash);
2731 =head2 update_or_create
2735 =item Arguments: \%col_values, { key => $unique_constraint }?
2737 =item Return Value: $row_object
2741 $resultset->update_or_create({ col => $val, ... });
2743 Like L</find_or_create>, but if a row is found it is immediately updated via
2744 C<< $found_row->update (\%col_values) >>.
2747 Takes an optional C<key> attribute to search on a specific unique constraint.
2750 # In your application
2751 my $cd = $schema->resultset('CD')->update_or_create(
2753 artist => 'Massive Attack',
2754 title => 'Mezzanine',
2757 { key => 'cd_artist_title' }
2760 $cd->cd_to_producer->update_or_create({
2761 producer => $producer,
2767 B<Note>: Make sure to read the documentation of L</find> and understand the
2768 significance of the C<key> attribute, as its lack may skew your search, and
2769 subsequently result in spurious row creation.
2771 B<Note>: Take care when using C<update_or_create> with a table having
2772 columns with default values that you intend to be automatically
2773 supplied by the database (e.g. an auto_increment primary key column).
2774 In normal usage, the value of such columns should NOT be included at
2775 all in the call to C<update_or_create>, even when set to C<undef>.
2777 See also L</find> and L</find_or_create>. For information on how to declare
2778 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2780 If you need to know if an existing row was updated or a new one created use
2781 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2782 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2785 my $cd = $schema->resultset('CD')->update_or_new(
2787 artist => 'Massive Attack',
2788 title => 'Mezzanine',
2791 { key => 'cd_artist_title' }
2794 if( $cd->in_storage ) {
2801 sub update_or_create {
2803 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2804 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2806 my $row = $self->find($cond, $attrs);
2808 $row->update($cond);
2812 return $self->create($cond);
2815 =head2 update_or_new
2819 =item Arguments: \%col_values, { key => $unique_constraint }?
2821 =item Return Value: $rowobject
2825 $resultset->update_or_new({ col => $val, ... });
2827 Like L</find_or_new> but if a row is found it is immediately updated via
2828 C<< $found_row->update (\%col_values) >>.
2832 # In your application
2833 my $cd = $schema->resultset('CD')->update_or_new(
2835 artist => 'Massive Attack',
2836 title => 'Mezzanine',
2839 { key => 'cd_artist_title' }
2842 if ($cd->in_storage) {
2843 # the cd was updated
2846 # the cd is not yet in the database, let's insert it
2850 B<Note>: Make sure to read the documentation of L</find> and understand the
2851 significance of the C<key> attribute, as its lack may skew your search, and
2852 subsequently result in spurious new objects.
2854 B<Note>: Take care when using C<update_or_new> with a table having
2855 columns with default values that you intend to be automatically
2856 supplied by the database (e.g. an auto_increment primary key column).
2857 In normal usage, the value of such columns should NOT be included at
2858 all in the call to C<update_or_new>, even when set to C<undef>.
2860 See also L</find>, L</find_or_create> and L</find_or_new>.
2866 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2867 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2869 my $row = $self->find( $cond, $attrs );
2870 if ( defined $row ) {
2871 $row->update($cond);
2875 return $self->new_result($cond);
2882 =item Arguments: none
2884 =item Return Value: \@cache_objects | undef
2888 Gets the contents of the cache for the resultset, if the cache is set.
2890 The cache is populated either by using the L</prefetch> attribute to
2891 L</search> or by calling L</set_cache>.
2903 =item Arguments: \@cache_objects
2905 =item Return Value: \@cache_objects
2909 Sets the contents of the cache for the resultset. Expects an arrayref
2910 of objects of the same class as those produced by the resultset. Note that
2911 if the cache is set the resultset will return the cached objects rather
2912 than re-querying the database even if the cache attr is not set.
2914 The contents of the cache can also be populated by using the
2915 L</prefetch> attribute to L</search>.
2920 my ( $self, $data ) = @_;
2921 $self->throw_exception("set_cache requires an arrayref")
2922 if defined($data) && (ref $data ne 'ARRAY');
2923 $self->{all_cache} = $data;
2930 =item Arguments: none
2932 =item Return Value: undef
2936 Clears the cache for the resultset.
2941 shift->set_cache(undef);
2948 =item Arguments: none
2950 =item Return Value: true, if the resultset has been paginated
2958 return !!$self->{attrs}{page};
2965 =item Arguments: none
2967 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2975 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
2978 =head2 related_resultset
2982 =item Arguments: $relationship_name
2984 =item Return Value: $resultset
2988 Returns a related resultset for the supplied relationship name.
2990 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2994 sub related_resultset {
2995 my ($self, $rel) = @_;
2997 $self->{related_resultsets} ||= {};
2998 return $self->{related_resultsets}{$rel} ||= do {
2999 my $rsrc = $self->result_source;
3000 my $rel_info = $rsrc->relationship_info($rel);
3002 $self->throw_exception(
3003 "search_related: result source '" . $rsrc->source_name .
3004 "' has no such relationship $rel")
3007 my $attrs = $self->_chain_relationship($rel);
3009 my $join_count = $attrs->{seen_join}{$rel};
3011 my $alias = $self->result_source->storage
3012 ->relname_to_table_alias($rel, $join_count);
3014 # since this is search_related, and we already slid the select window inwards
3015 # (the select/as attrs were deleted in the beginning), we need to flip all
3016 # left joins to inner, so we get the expected results
3017 # read the comment on top of the actual function to see what this does
3018 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
3021 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3022 delete @{$attrs}{qw(result_class alias)};
3026 if (my $cache = $self->get_cache) {
3027 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
3028 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache||[]} }
3033 my $rel_source = $rsrc->related_source($rel);
3037 # The reason we do this now instead of passing the alias to the
3038 # search_rs below is that if you wrap/overload resultset on the
3039 # source you need to know what alias it's -going- to have for things
3040 # to work sanely (e.g. RestrictWithObject wants to be able to add
3041 # extra query restrictions, and these may need to be $alias.)
3043 my $rel_attrs = $rel_source->resultset_attributes;
3044 local $rel_attrs->{alias} = $alias;
3046 $rel_source->resultset
3050 where => $attrs->{where},
3053 $new->set_cache($new_cache) if $new_cache;
3058 =head2 current_source_alias
3062 =item Arguments: none
3064 =item Return Value: $source_alias
3068 Returns the current table alias for the result source this resultset is built
3069 on, that will be used in the SQL query. Usually it is C<me>.
3071 Currently the source alias that refers to the result set returned by a
3072 L</search>/L</find> family method depends on how you got to the resultset: it's
3073 C<me> by default, but eg. L</search_related> aliases it to the related result
3074 source name (and keeps C<me> referring to the original result set). The long
3075 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3076 (and make this method unnecessary).
3078 Thus it's currently necessary to use this method in predefined queries (see
3079 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3080 source alias of the current result set:
3082 # in a result set class
3084 my ($self, $user) = @_;
3086 my $me = $self->current_source_alias;
3088 return $self->search({
3089 "$me.modified" => $user->id,
3095 sub current_source_alias {
3098 return ($self->{attrs} || {})->{alias} || 'me';
3101 =head2 as_subselect_rs
3105 =item Arguments: none
3107 =item Return Value: $resultset
3111 Act as a barrier to SQL symbols. The resultset provided will be made into a
3112 "virtual view" by including it as a subquery within the from clause. From this
3113 point on, any joined tables are inaccessible to ->search on the resultset (as if
3114 it were simply where-filtered without joins). For example:
3116 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3118 # 'x' now pollutes the query namespace
3120 # So the following works as expected
3121 my $ok_rs = $rs->search({'x.other' => 1});
3123 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3124 # def) we look for one row with contradictory terms and join in another table
3125 # (aliased 'x_2') which we never use
3126 my $broken_rs = $rs->search({'x.name' => 'def'});
3128 my $rs2 = $rs->as_subselect_rs;
3130 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3131 my $not_joined_rs = $rs2->search({'x.other' => 1});
3133 # works as expected: finds a 'table' row related to two x rows (abc and def)
3134 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3136 Another example of when one might use this would be to select a subset of
3137 columns in a group by clause:
3139 my $rs = $schema->resultset('Bar')->search(undef, {
3140 group_by => [qw{ id foo_id baz_id }],
3141 })->as_subselect_rs->search(undef, {
3142 columns => [qw{ id foo_id }]
3145 In the above example normally columns would have to be equal to the group by,
3146 but because we isolated the group by into a subselect the above works.
3150 sub as_subselect_rs {
3153 my $attrs = $self->_resolved_attrs;
3155 my $fresh_rs = (ref $self)->new (
3156 $self->result_source
3159 # these pieces will be locked in the subquery
3160 delete $fresh_rs->{cond};
3161 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3163 return $fresh_rs->search( {}, {
3165 $attrs->{alias} => $self->as_query,
3166 -alias => $attrs->{alias},
3167 -rsrc => $self->result_source,
3169 alias => $attrs->{alias},
3173 # This code is called by search_related, and makes sure there
3174 # is clear separation between the joins before, during, and
3175 # after the relationship. This information is needed later
3176 # in order to properly resolve prefetch aliases (any alias
3177 # with a relation_chain_depth less than the depth of the
3178 # current prefetch is not considered)
3180 # The increments happen twice per join. An even number means a
3181 # relationship specified via a search_related, whereas an odd
3182 # number indicates a join/prefetch added via attributes
3184 # Also this code will wrap the current resultset (the one we
3185 # chain to) in a subselect IFF it contains limiting attributes
3186 sub _chain_relationship {
3187 my ($self, $rel) = @_;
3188 my $source = $self->result_source;
3189 my $attrs = { %{$self->{attrs}||{}} };
3191 # we need to take the prefetch the attrs into account before we
3192 # ->_resolve_join as otherwise they get lost - captainL
3193 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3195 delete @{$attrs}{qw/join prefetch collapse group_by distinct select as columns +select +as +columns/};
3197 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3200 my @force_subq_attrs = qw/offset rows group_by having/;
3203 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3205 $self->_has_resolved_attr (@force_subq_attrs)
3207 # Nuke the prefetch (if any) before the new $rs attrs
3208 # are resolved (prefetch is useless - we are wrapping
3209 # a subquery anyway).
3210 my $rs_copy = $self->search;
3211 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3212 $rs_copy->{attrs}{join},
3213 delete $rs_copy->{attrs}{prefetch},
3218 -alias => $attrs->{alias},
3219 $attrs->{alias} => $rs_copy->as_query,
3221 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3222 $seen->{-relation_chain_depth} = 0;
3224 elsif ($attrs->{from}) { #shallow copy suffices
3225 $from = [ @{$attrs->{from}} ];
3230 -alias => $attrs->{alias},
3231 $attrs->{alias} => $source->from,
3235 my $jpath = ($seen->{-relation_chain_depth})
3236 ? $from->[-1][0]{-join_path}
3239 my @requested_joins = $source->_resolve_join(
3246 push @$from, @requested_joins;
3248 $seen->{-relation_chain_depth}++;
3250 # if $self already had a join/prefetch specified on it, the requested
3251 # $rel might very well be already included. What we do in this case
3252 # is effectively a no-op (except that we bump up the chain_depth on
3253 # the join in question so we could tell it *is* the search_related)
3256 # we consider the last one thus reverse
3257 for my $j (reverse @requested_joins) {
3258 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3259 if ($rel eq $last_j) {
3260 $j->[0]{-relation_chain_depth}++;
3266 unless ($already_joined) {
3267 push @$from, $source->_resolve_join(
3275 $seen->{-relation_chain_depth}++;
3277 return {%$attrs, from => $from, seen_join => $seen};
3280 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
3281 sub _resolved_attrs_copy {
3283 return { %{$self->_resolved_attrs (@_)} };
3286 sub _resolved_attrs {
3288 return $self->{_attrs} if $self->{_attrs};
3290 my $attrs = { %{ $self->{attrs} || {} } };
3291 my $source = $self->result_source;
3292 my $alias = $attrs->{alias};
3294 # default selection list
3295 $attrs->{columns} = [ $source->columns ]
3296 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3298 # merge selectors together
3299 for (qw/columns select as/) {
3300 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3301 if $attrs->{$_} or $attrs->{"+$_"};
3304 # disassemble columns
3306 if (my $cols = delete $attrs->{columns}) {
3307 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3308 if (ref $c eq 'HASH') {
3309 for my $as (keys %$c) {
3310 push @sel, $c->{$as};
3321 # when trying to weed off duplicates later do not go past this point -
3322 # everything added from here on is unbalanced "anyone's guess" stuff
3323 my $dedup_stop_idx = $#as;
3325 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3327 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3328 if $attrs->{select};
3330 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3331 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3333 # disqualify all $alias.col as-bits (inflate-map mandated)
3334 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3336 # de-duplicate the result (remove *identical* select/as pairs)
3337 # and also die on duplicate {as} pointing to different {select}s
3338 # not using a c-style for as the condition is prone to shrinkage
3341 while ($i <= $dedup_stop_idx) {
3342 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3347 elsif ($seen->{$as[$i]}++) {
3348 $self->throw_exception(
3349 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3357 $attrs->{select} = \@sel;
3358 $attrs->{as} = \@as;
3360 $attrs->{from} ||= [{
3362 -alias => $self->{attrs}{alias},
3363 $self->{attrs}{alias} => $source->from,
3366 if ( $attrs->{join} || $attrs->{prefetch} ) {
3368 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3369 if ref $attrs->{from} ne 'ARRAY';
3371 my $join = (delete $attrs->{join}) || {};
3373 if ( defined $attrs->{prefetch} ) {
3374 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3377 $attrs->{from} = # have to copy here to avoid corrupting the original
3379 @{ $attrs->{from} },
3380 $source->_resolve_join(
3383 { %{ $attrs->{seen_join} || {} } },
3384 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3385 ? $attrs->{from}[-1][0]{-join_path}
3392 if ( defined $attrs->{order_by} ) {
3393 $attrs->{order_by} = (
3394 ref( $attrs->{order_by} ) eq 'ARRAY'
3395 ? [ @{ $attrs->{order_by} } ]
3396 : [ $attrs->{order_by} || () ]
3400 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3401 $attrs->{group_by} = [ $attrs->{group_by} ];
3404 # generate the distinct induced group_by early, as prefetch will be carried via a
3405 # subquery (since a group_by is present)
3406 if (delete $attrs->{distinct}) {
3407 if ($attrs->{group_by}) {
3408 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3411 # distinct affects only the main selection part, not what prefetch may
3413 $attrs->{group_by} = $source->storage->_group_over_selection (
3421 # generate selections based on the prefetch helper
3423 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3424 if defined $attrs->{prefetch};
3428 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3429 if $attrs->{_dark_selector};
3431 $attrs->{collapse} = 1;
3433 # this is a separate structure (we don't look in {from} directly)
3434 # as the resolver needs to shift things off the lists to work
3435 # properly (identical-prefetches on different branches)
3437 if (ref $attrs->{from} eq 'ARRAY') {
3439 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3441 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3442 next unless $j->[0]{-alias};
3443 next unless $j->[0]{-join_path};
3444 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3446 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3449 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3450 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3454 my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map );
3456 # we need to somehow mark which columns came from prefetch
3458 my $sel_end = $#{$attrs->{select}};
3459 $attrs->{_prefetch_selector_range} = [ $sel_end + 1, $sel_end + @prefetch ];
3462 push @{ $attrs->{select} }, (map { $_->[0] } @prefetch);
3463 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
3466 $attrs->{_single_object_inflation} = ! List::Util::first { $_ =~ /\./ } @{$attrs->{as}};
3468 # run through the resulting joinstructure (starting from our current slot)
3469 # and unset collapse if proven unnesessary
3470 if ($attrs->{collapse} && ref $attrs->{from} eq 'ARRAY') {
3472 if (@{$attrs->{from}} > 1) {
3474 # find where our table-spec starts and consider only things after us
3475 my @fromlist = @{$attrs->{from}};
3477 my $t = shift @fromlist;
3478 $t = $t->[0] if ref $t eq 'ARRAY'; #me vs join from-spec mismatch
3479 last if ($t->{-alias} && $t->{-alias} eq $alias);
3483 $attrs->{collapse} = ! $_->[0]{-is_single}
3488 # no joins - no collapse
3489 $attrs->{collapse} = 0;
3493 if (! $attrs->{order_by} and $attrs->{collapse}) {
3494 # default order for collapsing unless the user asked for something
3495 $attrs->{order_by} = [ map { "$alias.$_" } $source->primary_columns ];
3496 $attrs->{_ordered_for_collapse} = 1;
3499 # if both page and offset are specified, produce a combined offset
3500 # even though it doesn't make much sense, this is what pre 081xx has
3502 if (my $page = delete $attrs->{page}) {
3504 ($attrs->{rows} * ($page - 1))
3506 ($attrs->{offset} || 0)
3510 return $self->{_attrs} = $attrs;
3514 my ($self, $attr) = @_;
3516 if (ref $attr eq 'HASH') {
3517 return $self->_rollout_hash($attr);
3518 } elsif (ref $attr eq 'ARRAY') {
3519 return $self->_rollout_array($attr);
3525 sub _rollout_array {
3526 my ($self, $attr) = @_;
3529 foreach my $element (@{$attr}) {
3530 if (ref $element eq 'HASH') {
3531 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3532 } elsif (ref $element eq 'ARRAY') {
3533 # XXX - should probably recurse here
3534 push( @rolled_array, @{$self->_rollout_array($element)} );
3536 push( @rolled_array, $element );
3539 return \@rolled_array;
3543 my ($self, $attr) = @_;
3546 foreach my $key (keys %{$attr}) {
3547 push( @rolled_array, { $key => $attr->{$key} } );
3549 return \@rolled_array;
3552 sub _calculate_score {
3553 my ($self, $a, $b) = @_;
3555 if (defined $a xor defined $b) {
3558 elsif (not defined $a) {
3562 if (ref $b eq 'HASH') {
3563 my ($b_key) = keys %{$b};
3564 if (ref $a eq 'HASH') {
3565 my ($a_key) = keys %{$a};
3566 if ($a_key eq $b_key) {
3567 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3572 return ($a eq $b_key) ? 1 : 0;
3575 if (ref $a eq 'HASH') {
3576 my ($a_key) = keys %{$a};
3577 return ($b eq $a_key) ? 1 : 0;
3579 return ($b eq $a) ? 1 : 0;
3584 sub _merge_joinpref_attr {
3585 my ($self, $orig, $import) = @_;
3587 return $import unless defined($orig);
3588 return $orig unless defined($import);
3590 $orig = $self->_rollout_attr($orig);
3591 $import = $self->_rollout_attr($import);
3594 foreach my $import_element ( @{$import} ) {
3595 # find best candidate from $orig to merge $b_element into
3596 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3597 foreach my $orig_element ( @{$orig} ) {
3598 my $score = $self->_calculate_score( $orig_element, $import_element );
3599 if ($score > $best_candidate->{score}) {
3600 $best_candidate->{position} = $position;
3601 $best_candidate->{score} = $score;
3605 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3606 $import_key = '' if not defined $import_key;
3608 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3609 push( @{$orig}, $import_element );
3611 my $orig_best = $orig->[$best_candidate->{position}];
3612 # merge orig_best and b_element together and replace original with merged
3613 if (ref $orig_best ne 'HASH') {
3614 $orig->[$best_candidate->{position}] = $import_element;
3615 } elsif (ref $import_element eq 'HASH') {
3616 my ($key) = keys %{$orig_best};
3617 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3620 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3631 require Hash::Merge;
3632 my $hm = Hash::Merge->new;
3634 $hm->specify_behavior({
3637 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3639 if ($defl xor $defr) {
3640 return [ $defl ? $_[0] : $_[1] ];
3645 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3649 return [$_[0], $_[1]];
3653 return $_[1] if !defined $_[0];
3654 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3655 return [$_[0], @{$_[1]}]
3658 return [] if !defined $_[0] and !keys %{$_[1]};
3659 return [ $_[1] ] if !defined $_[0];
3660 return [ $_[0] ] if !keys %{$_[1]};
3661 return [$_[0], $_[1]]
3666 return $_[0] if !defined $_[1];
3667 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3668 return [@{$_[0]}, $_[1]]
3671 my @ret = @{$_[0]} or return $_[1];
3672 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3673 my %idx = map { $_ => 1 } @ret;
3674 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3678 return [ $_[1] ] if ! @{$_[0]};
3679 return $_[0] if !keys %{$_[1]};
3680 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3681 return [ @{$_[0]}, $_[1] ];
3686 return [] if !keys %{$_[0]} and !defined $_[1];
3687 return [ $_[0] ] if !defined $_[1];
3688 return [ $_[1] ] if !keys %{$_[0]};
3689 return [$_[0], $_[1]]
3692 return [] if !keys %{$_[0]} and !@{$_[1]};
3693 return [ $_[0] ] if !@{$_[1]};
3694 return $_[1] if !keys %{$_[0]};
3695 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3696 return [ $_[0], @{$_[1]} ];
3699 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3700 return [ $_[0] ] if !keys %{$_[1]};
3701 return [ $_[1] ] if !keys %{$_[0]};
3702 return [ $_[0] ] if $_[0] eq $_[1];
3703 return [ $_[0], $_[1] ];
3706 } => 'DBIC_RS_ATTR_MERGER');
3710 return $hm->merge ($_[1], $_[2]);
3714 sub STORABLE_freeze {
3715 my ($self, $cloning) = @_;
3716 my $to_serialize = { %$self };
3718 # A cursor in progress can't be serialized (and would make little sense anyway)
3719 delete $to_serialize->{cursor};
3721 # the parser can be regenerated
3722 delete $to_serialize->{_row_parser};
3724 # nor is it sensical to store a not-yet-fired-count pager
3725 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3726 delete $to_serialize->{pager};
3729 Storable::nfreeze($to_serialize);
3732 # need this hook for symmetry
3734 my ($self, $cloning, $serialized) = @_;
3736 %$self = %{ Storable::thaw($serialized) };
3742 =head2 throw_exception
3744 See L<DBIx::Class::Schema/throw_exception> for details.
3748 sub throw_exception {
3751 if (ref $self and my $rsrc = $self->result_source) {
3752 $rsrc->throw_exception(@_)
3755 DBIx::Class::Exception->throw(@_);
3759 # XXX: FIXME: Attributes docs need clearing up
3763 Attributes are used to refine a ResultSet in various ways when
3764 searching for data. They can be passed to any method which takes an
3765 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3768 These are in no particular order:
3774 =item Value: ( $order_by | \@order_by | \%order_by )
3778 Which column(s) to order the results by.
3780 [The full list of suitable values is documented in
3781 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3784 If a single column name, or an arrayref of names is supplied, the
3785 argument is passed through directly to SQL. The hashref syntax allows
3786 for connection-agnostic specification of ordering direction:
3788 For descending order:
3790 order_by => { -desc => [qw/col1 col2 col3/] }
3792 For explicit ascending order:
3794 order_by => { -asc => 'col' }
3796 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3797 supported, although you are strongly encouraged to use the hashref
3798 syntax as outlined above.
3804 =item Value: \@columns
3808 Shortcut to request a particular set of columns to be retrieved. Each
3809 column spec may be a string (a table column name), or a hash (in which
3810 case the key is the C<as> value, and the value is used as the C<select>
3811 expression). Adds C<me.> onto the start of any column without a C<.> in
3812 it and sets C<select> from that, then auto-populates C<as> from
3813 C<select> as normal. (You may also use the C<cols> attribute, as in
3814 earlier versions of DBIC.)
3816 Essentially C<columns> does the same as L</select> and L</as>.
3818 columns => [ 'foo', { bar => 'baz' } ]
3822 select => [qw/foo baz/],
3829 =item Value: \@columns
3833 Indicates additional columns to be selected from storage. Works the same
3834 as L</columns> but adds columns to the selection. (You may also use the
3835 C<include_columns> attribute, as in earlier versions of DBIC). For
3838 $schema->resultset('CD')->search(undef, {
3839 '+columns' => ['artist.name'],
3843 would return all CDs and include a 'name' column to the information
3844 passed to object inflation. Note that the 'artist' is the name of the
3845 column (or relationship) accessor, and 'name' is the name of the column
3846 accessor in the related table.
3848 B<NOTE:> You need to explicitly quote '+columns' when defining the attribute.
3849 Not doing so causes Perl to incorrectly interpret +columns as a bareword with a
3850 unary plus operator before it.
3852 =head2 include_columns
3856 =item Value: \@columns
3860 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3866 =item Value: \@select_columns
3870 Indicates which columns should be selected from the storage. You can use
3871 column names, or in the case of RDBMS back ends, function or stored procedure
3874 $rs = $schema->resultset('Employee')->search(undef, {
3877 { count => 'employeeid' },
3878 { max => { length => 'name' }, -as => 'longest_name' }
3883 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
3885 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
3886 use L</select>, to instruct DBIx::Class how to store the result of the column.
3887 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
3888 identifier aliasing. You can however alias a function, so you can use it in
3889 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
3890 attribute> supplied as shown in the example above.
3892 B<NOTE:> You need to explicitly quote '+select'/'+as' when defining the attributes.
3893 Not doing so causes Perl to incorrectly interpret them as a bareword with a
3894 unary plus operator before it.
3900 Indicates additional columns to be selected from storage. Works the same as
3901 L</select> but adds columns to the default selection, instead of specifying
3910 Indicates additional column names for those added via L</+select>. See L</as>.
3918 =item Value: \@inflation_names
3922 Indicates column names for object inflation. That is L</as> indicates the
3923 slot name in which the column value will be stored within the
3924 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
3925 identifier by the C<get_column> method (or via the object accessor B<if one
3926 with the same name already exists>) as shown below. The L</as> attribute has
3927 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
3929 $rs = $schema->resultset('Employee')->search(undef, {
3932 { count => 'employeeid' },
3933 { max => { length => 'name' }, -as => 'longest_name' }
3942 If the object against which the search is performed already has an accessor
3943 matching a column name specified in C<as>, the value can be retrieved using
3944 the accessor as normal:
3946 my $name = $employee->name();
3948 If on the other hand an accessor does not exist in the object, you need to
3949 use C<get_column> instead:
3951 my $employee_count = $employee->get_column('employee_count');
3953 You can create your own accessors if required - see
3954 L<DBIx::Class::Manual::Cookbook> for details.
3960 =item Value: ($rel_name | \@rel_names | \%rel_names)
3964 Contains a list of relationships that should be joined for this query. For
3967 # Get CDs by Nine Inch Nails
3968 my $rs = $schema->resultset('CD')->search(
3969 { 'artist.name' => 'Nine Inch Nails' },
3970 { join => 'artist' }
3973 Can also contain a hash reference to refer to the other relation's relations.
3976 package MyApp::Schema::Track;
3977 use base qw/DBIx::Class/;
3978 __PACKAGE__->table('track');
3979 __PACKAGE__->add_columns(qw/trackid cd position title/);
3980 __PACKAGE__->set_primary_key('trackid');
3981 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3984 # In your application
3985 my $rs = $schema->resultset('Artist')->search(
3986 { 'track.title' => 'Teardrop' },
3988 join => { cd => 'track' },
3989 order_by => 'artist.name',
3993 You need to use the relationship (not the table) name in conditions,
3994 because they are aliased as such. The current table is aliased as "me", so
3995 you need to use me.column_name in order to avoid ambiguity. For example:
3997 # Get CDs from 1984 with a 'Foo' track
3998 my $rs = $schema->resultset('CD')->search(
4001 'tracks.name' => 'Foo'
4003 { join => 'tracks' }
4006 If the same join is supplied twice, it will be aliased to <rel>_2 (and
4007 similarly for a third time). For e.g.
4009 my $rs = $schema->resultset('Artist')->search({
4010 'cds.title' => 'Down to Earth',
4011 'cds_2.title' => 'Popular',
4013 join => [ qw/cds cds/ ],
4016 will return a set of all artists that have both a cd with title 'Down
4017 to Earth' and a cd with title 'Popular'.
4019 If you want to fetch related objects from other tables as well, see C<prefetch>
4022 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4028 =item Value: ($rel_name | \@rel_names | \%rel_names)
4032 Contains one or more relationships that should be fetched along with
4033 the main query (when they are accessed afterwards the data will
4034 already be available, without extra queries to the database). This is
4035 useful for when you know you will need the related objects, because it
4036 saves at least one query:
4038 my $rs = $schema->resultset('Tag')->search(
4047 The initial search results in SQL like the following:
4049 SELECT tag.*, cd.*, artist.* FROM tag
4050 JOIN cd ON tag.cd = cd.cdid
4051 JOIN artist ON cd.artist = artist.artistid
4053 L<DBIx::Class> has no need to go back to the database when we access the
4054 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4057 Simple prefetches will be joined automatically, so there is no need
4058 for a C<join> attribute in the above search.
4060 L</prefetch> can be used with the any of the relationship types and
4061 multiple prefetches can be specified together. Below is a more complex
4062 example that prefetches a CD's artist, its liner notes (if present),
4063 the cover image, the tracks on that cd, and the guests on those
4067 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4068 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4069 My::Schema::CD->has_one( cover_image => 'My::Schema::Artwork' );
4070 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4072 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4074 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4077 my $rs = $schema->resultset('CD')->search(
4081 { artist => 'record_label'}, # belongs_to => belongs_to
4082 'liner_note', # might_have
4083 'cover_image', # has_one
4084 { tracks => 'guests' }, # has_many => has_many
4089 This will produce SQL like the following:
4091 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4095 ON artist.artistid = me.artistid
4096 JOIN record_label record_label
4097 ON record_label.labelid = artist.labelid
4098 LEFT JOIN track tracks
4099 ON tracks.cdid = me.cdid
4100 LEFT JOIN guest guests
4101 ON guests.trackid = track.trackid
4102 LEFT JOIN liner_notes liner_note
4103 ON liner_note.cdid = me.cdid
4104 JOIN cd_artwork cover_image
4105 ON cover_image.cdid = me.cdid
4108 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4109 C<tracks>, and C<guests> of the CD will all be available through the
4110 relationship accessors without the need for additional queries to the
4113 However, there is one caveat to be observed: it can be dangerous to
4114 prefetch more than one L<has_many|DBIx::Class::Relationship/has_many>
4115 relationship on a given level. e.g.:
4117 my $rs = $schema->resultset('CD')->search(
4121 'tracks', # has_many
4122 { cd_to_producer => 'producer' }, # has_many => belongs_to (i.e. m2m)
4127 In fact, C<DBIx::Class> will emit the following warning:
4129 Prefetching multiple has_many rels tracks and cd_to_producer at top
4130 level will explode the number of row objects retrievable via ->next
4131 or ->all. Use at your own risk.
4133 The collapser currently can't identify duplicate tuples for multiple
4134 L<has_many|DBIx::Class::Relationship/has_many> relationships and as a
4135 result the second L<has_many|DBIx::Class::Relationship/has_many>
4136 relation could contain redundant objects.
4138 =head3 Using L</prefetch> with L</join>
4140 L</prefetch> implies a L</join> with the equivalent argument, and is
4141 properly merged with any existing L</join> specification. So the
4144 my $rs = $schema->resultset('CD')->search(
4145 {'record_label.name' => 'Music Product Ltd.'},
4147 join => {artist => 'record_label'},
4148 prefetch => 'artist',
4152 ... will work, searching on the record label's name, but only
4153 prefetching the C<artist>.
4155 =head3 Using L</prefetch> with L</select> / L</+select> / L</as> / L</+as>
4157 L</prefetch> implies a L</+select>/L</+as> with the fields of the
4158 prefetched relations. So given:
4160 my $rs = $schema->resultset('CD')->search(
4163 select => ['cd.title'],
4165 prefetch => 'artist',
4169 The L</select> becomes: C<'cd.title', 'artist.*'> and the L</as>
4170 becomes: C<'cd_title', 'artist.*'>.
4174 Prefetch does a lot of deep magic. As such, it may not behave exactly
4175 as you might expect.
4181 Prefetch uses the L</cache> to populate the prefetched relationships. This
4182 may or may not be what you want.
4186 If you specify a condition on a prefetched relationship, ONLY those
4187 rows that match the prefetched condition will be fetched into that relationship.
4188 This means that adding prefetch to a search() B<may alter> what is returned by
4189 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4191 my $artist_rs = $schema->resultset('Artist')->search({
4197 my $count = $artist_rs->first->cds->count;
4199 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4201 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4203 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4205 that cmp_ok() may or may not pass depending on the datasets involved. This
4206 behavior may or may not survive the 0.09 transition.
4218 Makes the resultset paged and specifies the page to retrieve. Effectively
4219 identical to creating a non-pages resultset and then calling ->page($page)
4222 If L</rows> attribute is not specified it defaults to 10 rows per page.
4224 When you have a paged resultset, L</count> will only return the number
4225 of rows in the page. To get the total, use the L</pager> and call
4226 C<total_entries> on it.
4236 Specifies the maximum number of rows for direct retrieval or the number of
4237 rows per page if the page attribute or method is used.
4243 =item Value: $offset
4247 Specifies the (zero-based) row number for the first row to be returned, or the
4248 of the first row of the first page if paging is used.
4250 =head2 software_limit
4254 =item Value: (0 | 1)
4258 When combined with L</rows> and/or L</offset> the generated SQL will not
4259 include any limit dialect stanzas. Instead the entire result will be selected
4260 as if no limits were specified, and DBIC will perform the limit locally, by
4261 artificially advancing and finishing the resulting L</cursor>.
4263 This is the recommended way of performing resultset limiting when no sane RDBMS
4264 implementation is available (e.g.
4265 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4266 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4272 =item Value: \@columns
4276 A arrayref of columns to group by. Can include columns of joined tables.
4278 group_by => [qw/ column1 column2 ... /]
4284 =item Value: $condition
4288 HAVING is a select statement attribute that is applied between GROUP BY and
4289 ORDER BY. It is applied to the after the grouping calculations have been
4292 having => { 'count_employee' => { '>=', 100 } }
4294 or with an in-place function in which case literal SQL is required:
4296 having => \[ 'count(employee) >= ?', [ count => 100 ] ]
4302 =item Value: (0 | 1)
4306 Set to 1 to group by all columns. If the resultset already has a group_by
4307 attribute, this setting is ignored and an appropriate warning is issued.
4313 Adds to the WHERE clause.
4315 # only return rows WHERE deleted IS NULL for all searches
4316 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
4318 Can be overridden by passing C<< { where => undef } >> as an attribute
4321 For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
4327 Set to 1 to cache search results. This prevents extra SQL queries if you
4328 revisit rows in your ResultSet:
4330 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4332 while( my $artist = $resultset->next ) {
4336 $rs->first; # without cache, this would issue a query
4338 By default, searches are not cached.
4340 For more examples of using these attributes, see
4341 L<DBIx::Class::Manual::Cookbook>.
4347 =item Value: ( 'update' | 'shared' )
4351 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT