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}, $attrs
1062 return @$data ? $self->_construct_objects($data)->[0] : undef;
1068 # Recursively collapse the query, accumulating values for each column.
1070 sub _collapse_query {
1071 my ($self, $query, $collapsed) = @_;
1075 if (ref $query eq 'ARRAY') {
1076 foreach my $subquery (@$query) {
1077 next unless ref $subquery; # -or
1078 $collapsed = $self->_collapse_query($subquery, $collapsed);
1081 elsif (ref $query eq 'HASH') {
1082 if (keys %$query and (keys %$query)[0] eq '-and') {
1083 foreach my $subquery (@{$query->{-and}}) {
1084 $collapsed = $self->_collapse_query($subquery, $collapsed);
1088 foreach my $col (keys %$query) {
1089 my $value = $query->{$col};
1090 $collapsed->{$col}{$value}++;
1102 =item Arguments: $cond?
1104 =item Return Value: $resultsetcolumn
1108 my $max_length = $rs->get_column('length')->max;
1110 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1115 my ($self, $column) = @_;
1116 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
1124 =item Arguments: $cond, \%attrs?
1126 =item Return Value: $resultset (scalar context) || @row_objs (list context)
1130 # WHERE title LIKE '%blue%'
1131 $cd_rs = $rs->search_like({ title => '%blue%'});
1133 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1134 that this is simply a convenience method retained for ex Class::DBI users.
1135 You most likely want to use L</search> with specific operators.
1137 For more information, see L<DBIx::Class::Manual::Cookbook>.
1139 This method is deprecated and will be removed in 0.09. Use L</search()>
1140 instead. An example conversion is:
1142 ->search_like({ foo => 'bar' });
1146 ->search({ foo => { like => 'bar' } });
1153 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1154 .' Instead use ->search({ x => { -like => "y%" } })'
1155 .' (note the outer pair of {}s - they are important!)'
1157 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1158 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1159 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1160 return $class->search($query, { %$attrs });
1167 =item Arguments: $first, $last
1169 =item Return Value: $resultset (scalar context) || @row_objs (list context)
1173 Returns a resultset or object list representing a subset of elements from the
1174 resultset slice is called on. Indexes are from 0, i.e., to get the first
1175 three records, call:
1177 my ($one, $two, $three) = $rs->slice(0, 2);
1182 my ($self, $min, $max) = @_;
1183 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1184 $attrs->{offset} = $self->{attrs}{offset} || 0;
1185 $attrs->{offset} += $min;
1186 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1187 return $self->search(undef, $attrs);
1188 #my $slice = (ref $self)->new($self->result_source, $attrs);
1189 #return (wantarray ? $slice->all : $slice);
1196 =item Arguments: none
1198 =item Return Value: $result | undef
1202 Returns the next element in the resultset (C<undef> is there is none).
1204 Can be used to efficiently iterate over records in the resultset:
1206 my $rs = $schema->resultset('CD')->search;
1207 while (my $cd = $rs->next) {
1211 Note that you need to store the resultset object, and call C<next> on it.
1212 Calling C<< resultset('Table')->next >> repeatedly will always return the
1213 first record from the resultset.
1220 if (my $cache = $self->get_cache) {
1221 $self->{all_cache_position} ||= 0;
1222 return $cache->[$self->{all_cache_position}++];
1225 if ($self->{attrs}{cache}) {
1226 delete $self->{pager};
1227 $self->{all_cache_position} = 1;
1228 return ($self->all)[0];
1231 return shift(@{$self->{stashed_objects}}) if @{ $self->{stashed_objects}||[] };
1233 $self->{stashed_objects} = $self->_construct_objects
1236 return shift @{$self->{stashed_objects}};
1239 # takes a single DBI-row of data and coinstructs as many objects
1240 # as the resultset attributes call for.
1241 # This can be a bit of an action at a distance - it takes as an argument
1242 # the *current* cursor-row (already taken off the $sth), but if
1243 # collapsing is requested it will keep advancing the cursor either
1244 # until the current row-object is assembled (the collapser was able to
1245 # order the result sensibly) OR until the cursor is exhausted (an
1246 # unordered collapsing resultset effectively triggers ->all)
1247 sub _construct_objects {
1248 my ($self, $fetched_row, $fetch_all) = @_;
1250 my $attrs = $self->_resolved_attrs;
1251 my $unordered = 0; # will deal with this later
1253 # this will be used as both initial raw-row collector AND as a RV of
1254 # _construct_objects. Not regrowing the # array twice matters a lot...
1255 # a suprising amount actually
1258 # $fetch_all implies all() which means all stashes have been cleared
1259 # and the cursor reset
1261 # FIXME - we can do better, cursor->all (well a diff. method) should return a ref
1262 $rows = [ $self->cursor->all ];
1264 elsif ($unordered) {
1267 @{ delete $self->{stashed_rows} || []},
1271 else { # simple single object
1272 $rows = [ $fetched_row || ( @{$self->{stashed_rows}||[]} ? shift @{$self->{stashed_rows}} : [$self->cursor->next] ) ];
1275 return undef unless @{$rows->[0]||[]};
1277 my $rsrc = $self->result_source;
1278 my $res_class = $self->result_class;
1279 my $inflator = $res_class->can ('inflate_result')
1280 or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
1282 # construct a much simpler array->hash folder for the one-table cases right here
1283 if ($attrs->{_single_object_inflation} and ! $attrs->{collapse}) {
1284 # FIXME SUBOPTIMAL this is a very very very hot spot
1285 # while rather optimal we can *still* do much better, by
1286 # building a smarter [Row|HRI]::inflate_result(), and
1287 # switch to feeding it data via a much leaner interface
1289 my $infmap = $attrs->{as};
1290 my @as_idx = 0..$#$infmap;
1291 for my $r (@$rows) {
1292 $r = [{ map { $infmap->[$_] => $r->[$_] } @as_idx }]
1295 # FIXME - this seems to be faster than the hashmapper above, especially
1296 # on more rows, but need a better bench-environment to confirm
1298 # '$_ = [{ %s }] for @$rows',
1299 # join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap )
1303 push @$rows, @{$self->{stashed_rows}||[]};
1305 my $perl = $rsrc->_mk_row_parser({
1306 inflate_map => $attrs->{as},
1307 selection => $attrs->{select},
1308 collapse => $attrs->{collapse},
1309 unordered => $unordered,
1312 (eval "sub { no warnings; no strict; $perl }")->( # disable of strictures seems to have some effect, weird
1313 $rows, # modify in-place, shrinking/extending as necessary
1314 ($attrs->{collapse} and ! $fetch_all and ! $unordered)
1316 sub { my @r = $self->cursor->next or return undef; \@r },
1317 ($self->{stashed_rows} = []), # this is where we empty things and prepare for leftovers
1324 $_ = $res_class->$inflator($rsrc, @$_) for @$rows;
1327 if ($attrs->{record_filter}) {
1328 $_ = $attrs->{record_filter}->($_) for @$rows;
1334 =head2 result_source
1338 =item Arguments: $result_source?
1340 =item Return Value: $result_source
1344 An accessor for the primary ResultSource object from which this ResultSet
1351 =item Arguments: $result_class?
1353 =item Return Value: $result_class
1357 An accessor for the class to use when creating row objects. Defaults to
1358 C<< result_source->result_class >> - which in most cases is the name of the
1359 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1361 Note that changing the result_class will also remove any components
1362 that were originally loaded in the source class via
1363 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1364 in the original source class will not run.
1369 my ($self, $result_class) = @_;
1370 if ($result_class) {
1371 unless (ref $result_class) { # don't fire this for an object
1372 $self->ensure_class_loaded($result_class);
1374 $self->_result_class($result_class);
1375 # THIS LINE WOULD BE A BUG - this accessor specifically exists to
1376 # permit the user to set result class on one result set only; it only
1377 # chains if provided to search()
1378 #$self->{attrs}{result_class} = $result_class if ref $self;
1380 $self->_result_class;
1387 =item Arguments: $cond, \%attrs??
1389 =item Return Value: $count
1393 Performs an SQL C<COUNT> with the same query as the resultset was built
1394 with to find the number of elements. Passing arguments is equivalent to
1395 C<< $rs->search ($cond, \%attrs)->count >>
1401 return $self->search(@_)->count if @_ and defined $_[0];
1402 return scalar @{ $self->get_cache } if $self->get_cache;
1404 my $attrs = $self->_resolved_attrs_copy;
1406 # this is a little optimization - it is faster to do the limit
1407 # adjustments in software, instead of a subquery
1408 my $rows = delete $attrs->{rows};
1409 my $offset = delete $attrs->{offset};
1412 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1413 $crs = $self->_count_subq_rs ($attrs);
1416 $crs = $self->_count_rs ($attrs);
1418 my $count = $crs->next;
1420 $count -= $offset if $offset;
1421 $count = $rows if $rows and $rows < $count;
1422 $count = 0 if ($count < 0);
1431 =item Arguments: $cond, \%attrs??
1433 =item Return Value: $count_rs
1437 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1438 This can be very handy for subqueries:
1440 ->search( { amount => $some_rs->count_rs->as_query } )
1442 As with regular resultsets the SQL query will be executed only after
1443 the resultset is accessed via L</next> or L</all>. That would return
1444 the same single value obtainable via L</count>.
1450 return $self->search(@_)->count_rs if @_;
1452 # this may look like a lack of abstraction (count() does about the same)
1453 # but in fact an _rs *must* use a subquery for the limits, as the
1454 # software based limiting can not be ported if this $rs is to be used
1455 # in a subquery itself (i.e. ->as_query)
1456 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1457 return $self->_count_subq_rs;
1460 return $self->_count_rs;
1465 # returns a ResultSetColumn object tied to the count query
1468 my ($self, $attrs) = @_;
1470 my $rsrc = $self->result_source;
1471 $attrs ||= $self->_resolved_attrs;
1473 my $tmp_attrs = { %$attrs };
1474 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1475 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1477 # overwrite the selector (supplied by the storage)
1478 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $attrs);
1479 $tmp_attrs->{as} = 'count';
1480 delete @{$tmp_attrs}{qw/columns/};
1482 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1488 # same as above but uses a subquery
1490 sub _count_subq_rs {
1491 my ($self, $attrs) = @_;
1493 my $rsrc = $self->result_source;
1494 $attrs ||= $self->_resolved_attrs;
1496 my $sub_attrs = { %$attrs };
1497 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1498 delete @{$sub_attrs}{qw/collapse columns as select _prefetch_selector_range order_by for/};
1500 # if we multi-prefetch we group_by something unique, as this is what we would
1501 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1502 if ( $attrs->{collapse} ) {
1503 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1504 $rsrc->_identifying_column_set || $self->throw_exception(
1505 'Unable to construct a unique group_by criteria properly collapsing the '
1506 . 'has_many prefetch before count()'
1511 # Calculate subquery selector
1512 if (my $g = $sub_attrs->{group_by}) {
1514 my $sql_maker = $rsrc->storage->sql_maker;
1516 # necessary as the group_by may refer to aliased functions
1518 for my $sel (@{$attrs->{select}}) {
1519 $sel_index->{$sel->{-as}} = $sel
1520 if (ref $sel eq 'HASH' and $sel->{-as});
1523 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1524 # also look for named aggregates referred in the having clause
1525 # having often contains scalarrefs - thus parse it out entirely
1527 if ($attrs->{having}) {
1528 local $sql_maker->{having_bind};
1529 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1530 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1531 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1532 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1533 # if we don't unset it we screw up retarded but unfortunately working
1534 # 'MAX(foo.bar)' => { '>', 3 }
1535 $sql_maker->{name_sep} = '';
1538 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1540 my $sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1542 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1543 # and if all fails for an utterly naive quoted scalar-with-function
1545 $rquote $sep $lquote (.+?) $rquote
1547 [\s,] \w+ \. (\w+) [\s,]
1549 [\s,] $lquote (.+?) $rquote [\s,]
1551 push @parts, ($1 || $2 || $3); # one of them matched if we got here
1556 my $colpiece = $sel_index->{$_} || $_;
1558 # unqualify join-based group_by's. Arcane but possible query
1559 # also horrible horrible hack to alias a column (not a func.)
1560 # (probably need to introduce SQLA syntax)
1561 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1564 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1566 push @{$sub_attrs->{select}}, $colpiece;
1570 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1571 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1574 return $rsrc->resultset_class
1575 ->new ($rsrc, $sub_attrs)
1577 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1578 ->get_column ('count');
1585 =head2 count_literal
1589 =item Arguments: $sql_fragment, @bind_values
1591 =item Return Value: $count
1595 Counts the results in a literal query. Equivalent to calling L</search_literal>
1596 with the passed arguments, then L</count>.
1600 sub count_literal { shift->search_literal(@_)->count; }
1606 =item Arguments: none
1608 =item Return Value: @objects
1612 Returns all elements in the resultset.
1619 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1622 delete $self->{stashed_rows};
1623 delete $self->{stashed_objects};
1625 if (my $c = $self->get_cache) {
1629 $self->cursor->reset;
1631 my $objs = $self->_construct_objects(undef, 'fetch_all') || [];
1633 $self->set_cache($objs) if $self->{attrs}{cache};
1642 =item Arguments: none
1644 =item Return Value: $self
1648 Resets the resultset's cursor, so you can iterate through the elements again.
1649 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1656 delete $self->{_attrs};
1657 delete $self->{stashed_rows};
1658 delete $self->{stashed_objects};
1660 $self->{all_cache_position} = 0;
1661 $self->cursor->reset;
1669 =item Arguments: none
1671 =item Return Value: $object | undef
1675 Resets the resultset and returns an object for the first result (or C<undef>
1676 if the resultset is empty).
1681 return $_[0]->reset->next;
1687 # Determines whether and what type of subquery is required for the $rs operation.
1688 # If grouping is necessary either supplies its own, or verifies the current one
1689 # After all is done delegates to the proper storage method.
1691 sub _rs_update_delete {
1692 my ($self, $op, $values) = @_;
1694 my $cond = $self->{cond};
1695 my $rsrc = $self->result_source;
1696 my $storage = $rsrc->schema->storage;
1698 my $attrs = { %{$self->_resolved_attrs} };
1700 # "needs" is a strong word here - if the subquery is part of an IN clause - no point of
1701 # even adding the group_by. It will really be used only when composing a poor-man's
1702 # multicolumn-IN equivalent OR set
1703 my $needs_group_by_subq = defined $attrs->{group_by};
1705 # simplify the joinmap and maybe decide if a grouping (and thus subquery) is necessary
1706 my $relation_classifications;
1707 if (ref($attrs->{from}) eq 'ARRAY') {
1708 $attrs->{from} = $storage->_prune_unused_joins ($attrs->{from}, $attrs->{select}, $cond, $attrs);
1710 $relation_classifications = $storage->_resolve_aliastypes_from_select_args (
1711 [ @{$attrs->{from}}[1 .. $#{$attrs->{from}}] ],
1715 ) unless $needs_group_by_subq; # we already know we need a group, no point of resolving them
1718 $needs_group_by_subq ||= 1; # if {from} is unparseable assume the worst
1721 $needs_group_by_subq ||= exists $relation_classifications->{multiplying};
1723 # if no subquery - life is easy-ish
1725 $needs_group_by_subq
1727 keys %$relation_classifications # if any joins at all - need to wrap a subq
1729 $self->_has_resolved_attr(qw/rows offset/) # limits call for a subq
1731 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1732 # a condition containing 'me' or other table prefixes will not work
1733 # at all. What this code tries to do (badly) is to generate a condition
1734 # with the qualifiers removed, by exploiting the quote mechanism of sqla
1736 # this is atrocious and should be replaced by normal sqla introspection
1738 my ($sql, @bind) = do {
1739 my $sqla = $rsrc->storage->sql_maker;
1740 local $sqla->{_dequalify_idents} = 1;
1741 $sqla->_recurse_where($self->{cond});
1744 return $rsrc->storage->$op(
1746 $op eq 'update' ? $values : (),
1747 $self->{cond} ? \[$sql, @bind] : (),
1751 # we got this far - means it is time to wrap a subquery
1752 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1754 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1759 my $existing_group_by = delete $attrs->{group_by};
1761 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1762 delete $attrs->{$_} for qw/collapse select _prefetch_selector_range as/;
1763 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1764 $attrs->{group_by} = \ ''; # FIXME - this is an evil hack, it causes the optimiser to kick in and throw away the LEFT joins
1765 my $subrs = (ref $self)->new($rsrc, $attrs);
1767 if (@$idcols == 1) {
1768 return $storage->$op (
1770 $op eq 'update' ? $values : (),
1771 { $idcols->[0] => { -in => $subrs->as_query } },
1774 elsif ($storage->_use_multicolumn_in) {
1775 # This is hideously ugly, but SQLA does not understand multicol IN expressions
1776 my $sql_maker = $storage->sql_maker;
1777 my ($sql, @bind) = @${$subrs->as_query};
1778 $sql = sprintf ('(%s) IN %s', # the as_query already comes with a set of parenthesis
1779 join (', ', map { $sql_maker->_quote ($_) } @$idcols),
1783 return $storage->$op (
1785 $op eq 'update' ? $values : (),
1790 # if all else fails - get all primary keys and operate over a ORed set
1791 # wrap in a transaction for consistency
1792 # this is where the group_by starts to matter
1794 if ($needs_group_by_subq) {
1795 $subq_group_by = $attrs->{columns};
1797 # make sure if there is a supplied group_by it matches the columns compiled above
1798 # perfectly. Anything else can not be sanely executed on most databases so croak
1799 # right then and there
1800 if ($existing_group_by) {
1801 my @current_group_by = map
1802 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1807 join ("\x00", sort @current_group_by)
1809 join ("\x00", sort @$subq_group_by )
1811 $self->throw_exception (
1812 "You have just attempted a $op operation on a resultset which does group_by"
1813 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1814 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1815 . ' kind of queries. Please retry the operation with a modified group_by or'
1816 . ' without using one at all.'
1822 my $guard = $storage->txn_scope_guard;
1825 for my $row ($subrs->search({}, { group_by => $subq_group_by })->cursor->all) {
1826 push @op_condition, { map
1827 { $idcols->[$_] => $row->[$_] }
1832 my $res = $storage->$op (
1834 $op eq 'update' ? $values : (),
1848 =item Arguments: \%values
1850 =item Return Value: $storage_rv
1854 Sets the specified columns in the resultset to the supplied values in a
1855 single query. Note that this will not run any accessor/set_column/update
1856 triggers, nor will it update any row object instances derived from this
1857 resultset (this includes the contents of the L<resultset cache|/set_cache>
1858 if any). See L</update_all> if you need to execute any on-update
1859 triggers or cascades defined either by you or a
1860 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1862 The return value is a pass through of what the underlying
1863 storage backend returned, and may vary. See L<DBI/execute> for the most
1868 Note that L</update> does not process/deflate any of the values passed in.
1869 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
1870 ensure manually that any value passed to this method will stringify to
1871 something the RDBMS knows how to deal with. A notable example is the
1872 handling of L<DateTime> objects, for more info see:
1873 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
1878 my ($self, $values) = @_;
1879 $self->throw_exception('Values for update must be a hash')
1880 unless ref $values eq 'HASH';
1882 return $self->_rs_update_delete ('update', $values);
1889 =item Arguments: \%values
1891 =item Return Value: 1
1895 Fetches all objects and updates them one at a time via
1896 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
1897 triggers, while L</update> will not.
1902 my ($self, $values) = @_;
1903 $self->throw_exception('Values for update_all must be a hash')
1904 unless ref $values eq 'HASH';
1906 my $guard = $self->result_source->schema->txn_scope_guard;
1907 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
1916 =item Arguments: none
1918 =item Return Value: $storage_rv
1922 Deletes the rows matching this resultset in a single query. Note that this
1923 will not run any delete triggers, nor will it alter the
1924 L<in_storage|DBIx::Class::Row/in_storage> status of any row object instances
1925 derived from this resultset (this includes the contents of the
1926 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
1927 execute any on-delete triggers or cascades defined either by you or a
1928 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1930 The return value is a pass through of what the underlying storage backend
1931 returned, and may vary. See L<DBI/execute> for the most common case.
1937 $self->throw_exception('delete does not accept any arguments')
1940 return $self->_rs_update_delete ('delete');
1947 =item Arguments: none
1949 =item Return Value: 1
1953 Fetches all objects and deletes them one at a time via
1954 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
1955 triggers, while L</delete> will not.
1961 $self->throw_exception('delete_all does not accept any arguments')
1964 my $guard = $self->result_source->schema->txn_scope_guard;
1965 $_->delete for $self->all;
1974 =item Arguments: \@data;
1978 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1979 For the arrayref of hashrefs style each hashref should be a structure suitable
1980 for submitting to a $resultset->create(...) method.
1982 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1983 to insert the data, as this is a faster method.
1985 Otherwise, each set of data is inserted into the database using
1986 L<DBIx::Class::ResultSet/create>, and the resulting objects are
1987 accumulated into an array. The array itself, or an array reference
1988 is returned depending on scalar or list context.
1990 Example: Assuming an Artist Class that has many CDs Classes relating:
1992 my $Artist_rs = $schema->resultset("Artist");
1994 ## Void Context Example
1995 $Artist_rs->populate([
1996 { artistid => 4, name => 'Manufactured Crap', cds => [
1997 { title => 'My First CD', year => 2006 },
1998 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2001 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2002 { title => 'My parents sold me to a record company', year => 2005 },
2003 { title => 'Why Am I So Ugly?', year => 2006 },
2004 { title => 'I Got Surgery and am now Popular', year => 2007 }
2009 ## Array Context Example
2010 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
2011 { name => "Artist One"},
2012 { name => "Artist Two"},
2013 { name => "Artist Three", cds=> [
2014 { title => "First CD", year => 2007},
2015 { title => "Second CD", year => 2008},
2019 print $ArtistOne->name; ## response is 'Artist One'
2020 print $ArtistThree->cds->count ## reponse is '2'
2022 For the arrayref of arrayrefs style, the first element should be a list of the
2023 fieldsnames to which the remaining elements are rows being inserted. For
2026 $Arstist_rs->populate([
2027 [qw/artistid name/],
2028 [100, 'A Formally Unknown Singer'],
2029 [101, 'A singer that jumped the shark two albums ago'],
2030 [102, 'An actually cool singer'],
2033 Please note an important effect on your data when choosing between void and
2034 wantarray context. Since void context goes straight to C<insert_bulk> in
2035 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
2036 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
2037 create primary keys for you, you will find that your PKs are empty. In this
2038 case you will have to use the wantarray context in order to create those
2046 # cruft placed in standalone method
2047 my $data = $self->_normalize_populate_args(@_);
2049 return unless @$data;
2051 if(defined wantarray) {
2053 foreach my $item (@$data) {
2054 push(@created, $self->create($item));
2056 return wantarray ? @created : \@created;
2059 my $first = $data->[0];
2061 # if a column is a registered relationship, and is a non-blessed hash/array, consider
2062 # it relationship data
2063 my (@rels, @columns);
2064 my $rsrc = $self->result_source;
2065 my $rels = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2066 for (keys %$first) {
2067 my $ref = ref $first->{$_};
2068 $rels->{$_} && ($ref eq 'ARRAY' or $ref eq 'HASH')
2074 my @pks = $rsrc->primary_columns;
2076 ## do the belongs_to relationships
2077 foreach my $index (0..$#$data) {
2079 # delegate to create() for any dataset without primary keys with specified relationships
2080 if (grep { !defined $data->[$index]->{$_} } @pks ) {
2082 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
2083 my @ret = $self->populate($data);
2089 foreach my $rel (@rels) {
2090 next unless ref $data->[$index]->{$rel} eq "HASH";
2091 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
2092 my ($reverse_relname, $reverse_relinfo) = %{$rsrc->reverse_relationship_info($rel)};
2093 my $related = $result->result_source->_resolve_condition(
2094 $reverse_relinfo->{cond},
2100 delete $data->[$index]->{$rel};
2101 $data->[$index] = {%{$data->[$index]}, %$related};
2103 push @columns, keys %$related if $index == 0;
2107 ## inherit the data locked in the conditions of the resultset
2108 my ($rs_data) = $self->_merge_with_rscond({});
2109 delete @{$rs_data}{@columns};
2110 my @inherit_cols = keys %$rs_data;
2111 my @inherit_data = values %$rs_data;
2113 ## do bulk insert on current row
2114 $rsrc->storage->insert_bulk(
2116 [@columns, @inherit_cols],
2117 [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
2120 ## do the has_many relationships
2121 foreach my $item (@$data) {
2125 foreach my $rel (@rels) {
2126 next unless ref $item->{$rel} eq "ARRAY" && @{ $item->{$rel} };
2128 $main_row ||= $self->new_result({map { $_ => $item->{$_} } @pks});
2130 my $child = $main_row->$rel;
2132 my $related = $child->result_source->_resolve_condition(
2133 $rels->{$rel}{cond},
2139 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
2140 my @populate = map { {%$_, %$related} } @rows_to_add;
2142 $child->populate( \@populate );
2149 # populate() argumnets went over several incarnations
2150 # What we ultimately support is AoH
2151 sub _normalize_populate_args {
2152 my ($self, $arg) = @_;
2154 if (ref $arg eq 'ARRAY') {
2158 elsif (ref $arg->[0] eq 'HASH') {
2161 elsif (ref $arg->[0] eq 'ARRAY') {
2163 my @colnames = @{$arg->[0]};
2164 foreach my $values (@{$arg}[1 .. $#$arg]) {
2165 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
2171 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2178 =item Arguments: none
2180 =item Return Value: $pager
2184 Return Value a L<Data::Page> object for the current resultset. Only makes
2185 sense for queries with a C<page> attribute.
2187 To get the full count of entries for a paged resultset, call
2188 C<total_entries> on the L<Data::Page> object.
2195 return $self->{pager} if $self->{pager};
2197 my $attrs = $self->{attrs};
2198 if (!defined $attrs->{page}) {
2199 $self->throw_exception("Can't create pager for non-paged rs");
2201 elsif ($attrs->{page} <= 0) {
2202 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2204 $attrs->{rows} ||= 10;
2206 # throw away the paging flags and re-run the count (possibly
2207 # with a subselect) to get the real total count
2208 my $count_attrs = { %$attrs };
2209 delete $count_attrs->{$_} for qw/rows offset page pager/;
2211 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2213 require DBIx::Class::ResultSet::Pager;
2214 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2215 sub { $total_rs->count }, #lazy-get the total
2217 $self->{attrs}{page},
2225 =item Arguments: $page_number
2227 =item Return Value: $rs
2231 Returns a resultset for the $page_number page of the resultset on which page
2232 is called, where each page contains a number of rows equal to the 'rows'
2233 attribute set on the resultset (10 by default).
2238 my ($self, $page) = @_;
2239 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2246 =item Arguments: \%vals
2248 =item Return Value: $rowobject
2252 Creates a new row object in the resultset's result class and returns
2253 it. The row is not inserted into the database at this point, call
2254 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2255 will tell you whether the row object has been inserted or not.
2257 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2262 my ($self, $values) = @_;
2263 $self->throw_exception( "new_result needs a hash" )
2264 unless (ref $values eq 'HASH');
2266 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2270 @$cols_from_relations
2271 ? (-cols_from_relations => $cols_from_relations)
2273 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2276 return $self->result_class->new(\%new);
2279 # _merge_with_rscond
2281 # Takes a simple hash of K/V data and returns its copy merged with the
2282 # condition already present on the resultset. Additionally returns an
2283 # arrayref of value/condition names, which were inferred from related
2284 # objects (this is needed for in-memory related objects)
2285 sub _merge_with_rscond {
2286 my ($self, $data) = @_;
2288 my (%new_data, @cols_from_relations);
2290 my $alias = $self->{attrs}{alias};
2292 if (! defined $self->{cond}) {
2293 # just massage $data below
2295 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
2296 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
2297 @cols_from_relations = keys %new_data;
2299 elsif (ref $self->{cond} ne 'HASH') {
2300 $self->throw_exception(
2301 "Can't abstract implicit construct, resultset condition not a hash"
2305 # precendence must be given to passed values over values inherited from
2306 # the cond, so the order here is important.
2307 my $collapsed_cond = $self->_collapse_cond($self->{cond});
2308 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
2310 while ( my($col, $value) = each %implied ) {
2311 my $vref = ref $value;
2317 (keys %$value)[0] eq '='
2319 $new_data{$col} = $value->{'='};
2321 elsif( !$vref or $vref eq 'SCALAR' or blessed($value) ) {
2322 $new_data{$col} = $value;
2329 %{ $self->_remove_alias($data, $alias) },
2332 return (\%new_data, \@cols_from_relations);
2335 # _has_resolved_attr
2337 # determines if the resultset defines at least one
2338 # of the attributes supplied
2340 # used to determine if a subquery is neccessary
2342 # supports some virtual attributes:
2344 # This will scan for any joins being present on the resultset.
2345 # It is not a mere key-search but a deep inspection of {from}
2348 sub _has_resolved_attr {
2349 my ($self, @attr_names) = @_;
2351 my $attrs = $self->_resolved_attrs;
2355 for my $n (@attr_names) {
2356 if (grep { $n eq $_ } (qw/-join/) ) {
2357 $extra_checks{$n}++;
2361 my $attr = $attrs->{$n};
2363 next if not defined $attr;
2365 if (ref $attr eq 'HASH') {
2366 return 1 if keys %$attr;
2368 elsif (ref $attr eq 'ARRAY') {
2376 # a resolved join is expressed as a multi-level from
2378 $extra_checks{-join}
2380 ref $attrs->{from} eq 'ARRAY'
2382 @{$attrs->{from}} > 1
2390 # Recursively collapse the condition.
2392 sub _collapse_cond {
2393 my ($self, $cond, $collapsed) = @_;
2397 if (ref $cond eq 'ARRAY') {
2398 foreach my $subcond (@$cond) {
2399 next unless ref $subcond; # -or
2400 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2403 elsif (ref $cond eq 'HASH') {
2404 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2405 foreach my $subcond (@{$cond->{-and}}) {
2406 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2410 foreach my $col (keys %$cond) {
2411 my $value = $cond->{$col};
2412 $collapsed->{$col} = $value;
2422 # Remove the specified alias from the specified query hash. A copy is made so
2423 # the original query is not modified.
2426 my ($self, $query, $alias) = @_;
2428 my %orig = %{ $query || {} };
2431 foreach my $key (keys %orig) {
2433 $unaliased{$key} = $orig{$key};
2436 $unaliased{$1} = $orig{$key}
2437 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2447 =item Arguments: none
2449 =item Return Value: \[ $sql, @bind ]
2453 Returns the SQL query and bind vars associated with the invocant.
2455 This is generally used as the RHS for a subquery.
2462 my $attrs = $self->_resolved_attrs_copy;
2467 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2468 # $sql also has no wrapping parenthesis in list ctx
2470 my $sqlbind = $self->result_source->storage
2471 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2480 =item Arguments: \%vals, \%attrs?
2482 =item Return Value: $rowobject
2486 my $artist = $schema->resultset('Artist')->find_or_new(
2487 { artist => 'fred' }, { key => 'artists' });
2489 $cd->cd_to_producer->find_or_new({ producer => $producer },
2490 { key => 'primary });
2492 Find an existing record from this resultset using L</find>. if none exists,
2493 instantiate a new result object and return it. The object will not be saved
2494 into your storage until you call L<DBIx::Class::Row/insert> on it.
2496 You most likely want this method when looking for existing rows using a unique
2497 constraint that is not the primary key, or looking for related rows.
2499 If you want objects to be saved immediately, use L</find_or_create> instead.
2501 B<Note>: Make sure to read the documentation of L</find> and understand the
2502 significance of the C<key> attribute, as its lack may skew your search, and
2503 subsequently result in spurious new objects.
2505 B<Note>: Take care when using C<find_or_new> with a table having
2506 columns with default values that you intend to be automatically
2507 supplied by the database (e.g. an auto_increment primary key column).
2508 In normal usage, the value of such columns should NOT be included at
2509 all in the call to C<find_or_new>, even when set to C<undef>.
2515 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2516 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2517 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2520 return $self->new_result($hash);
2527 =item Arguments: \%vals
2529 =item Return Value: a L<DBIx::Class::Row> $object
2533 Attempt to create a single new row or a row with multiple related rows
2534 in the table represented by the resultset (and related tables). This
2535 will not check for duplicate rows before inserting, use
2536 L</find_or_create> to do that.
2538 To create one row for this resultset, pass a hashref of key/value
2539 pairs representing the columns of the table and the values you wish to
2540 store. If the appropriate relationships are set up, foreign key fields
2541 can also be passed an object representing the foreign row, and the
2542 value will be set to its primary key.
2544 To create related objects, pass a hashref of related-object column values
2545 B<keyed on the relationship name>. If the relationship is of type C<multi>
2546 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2547 The process will correctly identify columns holding foreign keys, and will
2548 transparently populate them from the keys of the corresponding relation.
2549 This can be applied recursively, and will work correctly for a structure
2550 with an arbitrary depth and width, as long as the relationships actually
2551 exists and the correct column data has been supplied.
2554 Instead of hashrefs of plain related data (key/value pairs), you may
2555 also pass new or inserted objects. New objects (not inserted yet, see
2556 L</new>), will be inserted into their appropriate tables.
2558 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2560 Example of creating a new row.
2562 $person_rs->create({
2563 name=>"Some Person",
2564 email=>"somebody@someplace.com"
2567 Example of creating a new row and also creating rows in a related C<has_many>
2568 or C<has_one> resultset. Note Arrayref.
2571 { artistid => 4, name => 'Manufactured Crap', cds => [
2572 { title => 'My First CD', year => 2006 },
2573 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2578 Example of creating a new row and also creating a row in a related
2579 C<belongs_to> resultset. Note Hashref.
2582 title=>"Music for Silly Walks",
2585 name=>"Silly Musician",
2593 When subclassing ResultSet never attempt to override this method. Since
2594 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2595 lot of the internals simply never call it, so your override will be
2596 bypassed more often than not. Override either L<new|DBIx::Class::Row/new>
2597 or L<insert|DBIx::Class::Row/insert> depending on how early in the
2598 L</create> process you need to intervene.
2605 my ($self, $attrs) = @_;
2606 $self->throw_exception( "create needs a hashref" )
2607 unless ref $attrs eq 'HASH';
2608 return $self->new_result($attrs)->insert;
2611 =head2 find_or_create
2615 =item Arguments: \%vals, \%attrs?
2617 =item Return Value: $rowobject
2621 $cd->cd_to_producer->find_or_create({ producer => $producer },
2622 { key => 'primary' });
2624 Tries to find a record based on its primary key or unique constraints; if none
2625 is found, creates one and returns that instead.
2627 my $cd = $schema->resultset('CD')->find_or_create({
2629 artist => 'Massive Attack',
2630 title => 'Mezzanine',
2634 Also takes an optional C<key> attribute, to search by a specific key or unique
2635 constraint. For example:
2637 my $cd = $schema->resultset('CD')->find_or_create(
2639 artist => 'Massive Attack',
2640 title => 'Mezzanine',
2642 { key => 'cd_artist_title' }
2645 B<Note>: Make sure to read the documentation of L</find> and understand the
2646 significance of the C<key> attribute, as its lack may skew your search, and
2647 subsequently result in spurious row creation.
2649 B<Note>: Because find_or_create() reads from the database and then
2650 possibly inserts based on the result, this method is subject to a race
2651 condition. Another process could create a record in the table after
2652 the find has completed and before the create has started. To avoid
2653 this problem, use find_or_create() inside a transaction.
2655 B<Note>: Take care when using C<find_or_create> with a table having
2656 columns with default values that you intend to be automatically
2657 supplied by the database (e.g. an auto_increment primary key column).
2658 In normal usage, the value of such columns should NOT be included at
2659 all in the call to C<find_or_create>, even when set to C<undef>.
2661 See also L</find> and L</update_or_create>. For information on how to declare
2662 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2664 If you need to know if an existing row was found or a new one created use
2665 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2666 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2669 my $cd = $schema->resultset('CD')->find_or_new({
2671 artist => 'Massive Attack',
2672 title => 'Mezzanine',
2676 if( $cd->in_storage ) {
2683 sub find_or_create {
2685 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2686 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2687 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2690 return $self->create($hash);
2693 =head2 update_or_create
2697 =item Arguments: \%col_values, { key => $unique_constraint }?
2699 =item Return Value: $row_object
2703 $resultset->update_or_create({ col => $val, ... });
2705 Like L</find_or_create>, but if a row is found it is immediately updated via
2706 C<< $found_row->update (\%col_values) >>.
2709 Takes an optional C<key> attribute to search on a specific unique constraint.
2712 # In your application
2713 my $cd = $schema->resultset('CD')->update_or_create(
2715 artist => 'Massive Attack',
2716 title => 'Mezzanine',
2719 { key => 'cd_artist_title' }
2722 $cd->cd_to_producer->update_or_create({
2723 producer => $producer,
2729 B<Note>: Make sure to read the documentation of L</find> and understand the
2730 significance of the C<key> attribute, as its lack may skew your search, and
2731 subsequently result in spurious row creation.
2733 B<Note>: Take care when using C<update_or_create> with a table having
2734 columns with default values that you intend to be automatically
2735 supplied by the database (e.g. an auto_increment primary key column).
2736 In normal usage, the value of such columns should NOT be included at
2737 all in the call to C<update_or_create>, even when set to C<undef>.
2739 See also L</find> and L</find_or_create>. For information on how to declare
2740 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2742 If you need to know if an existing row was updated or a new one created use
2743 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2744 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2747 my $cd = $schema->resultset('CD')->update_or_new(
2749 artist => 'Massive Attack',
2750 title => 'Mezzanine',
2753 { key => 'cd_artist_title' }
2756 if( $cd->in_storage ) {
2763 sub update_or_create {
2765 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2766 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2768 my $row = $self->find($cond, $attrs);
2770 $row->update($cond);
2774 return $self->create($cond);
2777 =head2 update_or_new
2781 =item Arguments: \%col_values, { key => $unique_constraint }?
2783 =item Return Value: $rowobject
2787 $resultset->update_or_new({ col => $val, ... });
2789 Like L</find_or_new> but if a row is found it is immediately updated via
2790 C<< $found_row->update (\%col_values) >>.
2794 # In your application
2795 my $cd = $schema->resultset('CD')->update_or_new(
2797 artist => 'Massive Attack',
2798 title => 'Mezzanine',
2801 { key => 'cd_artist_title' }
2804 if ($cd->in_storage) {
2805 # the cd was updated
2808 # the cd is not yet in the database, let's insert it
2812 B<Note>: Make sure to read the documentation of L</find> and understand the
2813 significance of the C<key> attribute, as its lack may skew your search, and
2814 subsequently result in spurious new objects.
2816 B<Note>: Take care when using C<update_or_new> with a table having
2817 columns with default values that you intend to be automatically
2818 supplied by the database (e.g. an auto_increment primary key column).
2819 In normal usage, the value of such columns should NOT be included at
2820 all in the call to C<update_or_new>, even when set to C<undef>.
2822 See also L</find>, L</find_or_create> and L</find_or_new>.
2828 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2829 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2831 my $row = $self->find( $cond, $attrs );
2832 if ( defined $row ) {
2833 $row->update($cond);
2837 return $self->new_result($cond);
2844 =item Arguments: none
2846 =item Return Value: \@cache_objects | undef
2850 Gets the contents of the cache for the resultset, if the cache is set.
2852 The cache is populated either by using the L</prefetch> attribute to
2853 L</search> or by calling L</set_cache>.
2865 =item Arguments: \@cache_objects
2867 =item Return Value: \@cache_objects
2871 Sets the contents of the cache for the resultset. Expects an arrayref
2872 of objects of the same class as those produced by the resultset. Note that
2873 if the cache is set the resultset will return the cached objects rather
2874 than re-querying the database even if the cache attr is not set.
2876 The contents of the cache can also be populated by using the
2877 L</prefetch> attribute to L</search>.
2882 my ( $self, $data ) = @_;
2883 $self->throw_exception("set_cache requires an arrayref")
2884 if defined($data) && (ref $data ne 'ARRAY');
2885 $self->{all_cache} = $data;
2892 =item Arguments: none
2894 =item Return Value: undef
2898 Clears the cache for the resultset.
2903 shift->set_cache(undef);
2910 =item Arguments: none
2912 =item Return Value: true, if the resultset has been paginated
2920 return !!$self->{attrs}{page};
2927 =item Arguments: none
2929 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2937 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
2940 =head2 related_resultset
2944 =item Arguments: $relationship_name
2946 =item Return Value: $resultset
2950 Returns a related resultset for the supplied relationship name.
2952 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2956 sub related_resultset {
2957 my ($self, $rel) = @_;
2959 $self->{related_resultsets} ||= {};
2960 return $self->{related_resultsets}{$rel} ||= do {
2961 my $rsrc = $self->result_source;
2962 my $rel_info = $rsrc->relationship_info($rel);
2964 $self->throw_exception(
2965 "search_related: result source '" . $rsrc->source_name .
2966 "' has no such relationship $rel")
2969 my $attrs = $self->_chain_relationship($rel);
2971 my $join_count = $attrs->{seen_join}{$rel};
2973 my $alias = $self->result_source->storage
2974 ->relname_to_table_alias($rel, $join_count);
2976 # since this is search_related, and we already slid the select window inwards
2977 # (the select/as attrs were deleted in the beginning), we need to flip all
2978 # left joins to inner, so we get the expected results
2979 # read the comment on top of the actual function to see what this does
2980 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
2983 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2984 delete @{$attrs}{qw(result_class alias)};
2988 if (my $cache = $self->get_cache) {
2989 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2990 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache||[]} }
2995 my $rel_source = $rsrc->related_source($rel);
2999 # The reason we do this now instead of passing the alias to the
3000 # search_rs below is that if you wrap/overload resultset on the
3001 # source you need to know what alias it's -going- to have for things
3002 # to work sanely (e.g. RestrictWithObject wants to be able to add
3003 # extra query restrictions, and these may need to be $alias.)
3005 my $rel_attrs = $rel_source->resultset_attributes;
3006 local $rel_attrs->{alias} = $alias;
3008 $rel_source->resultset
3012 where => $attrs->{where},
3015 $new->set_cache($new_cache) if $new_cache;
3020 =head2 current_source_alias
3024 =item Arguments: none
3026 =item Return Value: $source_alias
3030 Returns the current table alias for the result source this resultset is built
3031 on, that will be used in the SQL query. Usually it is C<me>.
3033 Currently the source alias that refers to the result set returned by a
3034 L</search>/L</find> family method depends on how you got to the resultset: it's
3035 C<me> by default, but eg. L</search_related> aliases it to the related result
3036 source name (and keeps C<me> referring to the original result set). The long
3037 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3038 (and make this method unnecessary).
3040 Thus it's currently necessary to use this method in predefined queries (see
3041 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3042 source alias of the current result set:
3044 # in a result set class
3046 my ($self, $user) = @_;
3048 my $me = $self->current_source_alias;
3050 return $self->search({
3051 "$me.modified" => $user->id,
3057 sub current_source_alias {
3060 return ($self->{attrs} || {})->{alias} || 'me';
3063 =head2 as_subselect_rs
3067 =item Arguments: none
3069 =item Return Value: $resultset
3073 Act as a barrier to SQL symbols. The resultset provided will be made into a
3074 "virtual view" by including it as a subquery within the from clause. From this
3075 point on, any joined tables are inaccessible to ->search on the resultset (as if
3076 it were simply where-filtered without joins). For example:
3078 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3080 # 'x' now pollutes the query namespace
3082 # So the following works as expected
3083 my $ok_rs = $rs->search({'x.other' => 1});
3085 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3086 # def) we look for one row with contradictory terms and join in another table
3087 # (aliased 'x_2') which we never use
3088 my $broken_rs = $rs->search({'x.name' => 'def'});
3090 my $rs2 = $rs->as_subselect_rs;
3092 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3093 my $not_joined_rs = $rs2->search({'x.other' => 1});
3095 # works as expected: finds a 'table' row related to two x rows (abc and def)
3096 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3098 Another example of when one might use this would be to select a subset of
3099 columns in a group by clause:
3101 my $rs = $schema->resultset('Bar')->search(undef, {
3102 group_by => [qw{ id foo_id baz_id }],
3103 })->as_subselect_rs->search(undef, {
3104 columns => [qw{ id foo_id }]
3107 In the above example normally columns would have to be equal to the group by,
3108 but because we isolated the group by into a subselect the above works.
3112 sub as_subselect_rs {
3115 my $attrs = $self->_resolved_attrs;
3117 my $fresh_rs = (ref $self)->new (
3118 $self->result_source
3121 # these pieces will be locked in the subquery
3122 delete $fresh_rs->{cond};
3123 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3125 return $fresh_rs->search( {}, {
3127 $attrs->{alias} => $self->as_query,
3128 -alias => $attrs->{alias},
3129 -rsrc => $self->result_source,
3131 alias => $attrs->{alias},
3135 # This code is called by search_related, and makes sure there
3136 # is clear separation between the joins before, during, and
3137 # after the relationship. This information is needed later
3138 # in order to properly resolve prefetch aliases (any alias
3139 # with a relation_chain_depth less than the depth of the
3140 # current prefetch is not considered)
3142 # The increments happen twice per join. An even number means a
3143 # relationship specified via a search_related, whereas an odd
3144 # number indicates a join/prefetch added via attributes
3146 # Also this code will wrap the current resultset (the one we
3147 # chain to) in a subselect IFF it contains limiting attributes
3148 sub _chain_relationship {
3149 my ($self, $rel) = @_;
3150 my $source = $self->result_source;
3151 my $attrs = { %{$self->{attrs}||{}} };
3153 # we need to take the prefetch the attrs into account before we
3154 # ->_resolve_join as otherwise they get lost - captainL
3155 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3157 delete @{$attrs}{qw/join prefetch collapse group_by distinct select as columns +select +as +columns/};
3159 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3162 my @force_subq_attrs = qw/offset rows group_by having/;
3165 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3167 $self->_has_resolved_attr (@force_subq_attrs)
3169 # Nuke the prefetch (if any) before the new $rs attrs
3170 # are resolved (prefetch is useless - we are wrapping
3171 # a subquery anyway).
3172 my $rs_copy = $self->search;
3173 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3174 $rs_copy->{attrs}{join},
3175 delete $rs_copy->{attrs}{prefetch},
3180 -alias => $attrs->{alias},
3181 $attrs->{alias} => $rs_copy->as_query,
3183 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3184 $seen->{-relation_chain_depth} = 0;
3186 elsif ($attrs->{from}) { #shallow copy suffices
3187 $from = [ @{$attrs->{from}} ];
3192 -alias => $attrs->{alias},
3193 $attrs->{alias} => $source->from,
3197 my $jpath = ($seen->{-relation_chain_depth})
3198 ? $from->[-1][0]{-join_path}
3201 my @requested_joins = $source->_resolve_join(
3208 push @$from, @requested_joins;
3210 $seen->{-relation_chain_depth}++;
3212 # if $self already had a join/prefetch specified on it, the requested
3213 # $rel might very well be already included. What we do in this case
3214 # is effectively a no-op (except that we bump up the chain_depth on
3215 # the join in question so we could tell it *is* the search_related)
3218 # we consider the last one thus reverse
3219 for my $j (reverse @requested_joins) {
3220 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3221 if ($rel eq $last_j) {
3222 $j->[0]{-relation_chain_depth}++;
3228 unless ($already_joined) {
3229 push @$from, $source->_resolve_join(
3237 $seen->{-relation_chain_depth}++;
3239 return {%$attrs, from => $from, seen_join => $seen};
3242 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
3243 sub _resolved_attrs_copy {
3245 return { %{$self->_resolved_attrs (@_)} };
3248 sub _resolved_attrs {
3250 return $self->{_attrs} if $self->{_attrs};
3252 my $attrs = { %{ $self->{attrs} || {} } };
3253 my $source = $self->result_source;
3254 my $alias = $attrs->{alias};
3256 # default selection list
3257 $attrs->{columns} = [ $source->columns ]
3258 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3260 # merge selectors together
3261 for (qw/columns select as/) {
3262 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3263 if $attrs->{$_} or $attrs->{"+$_"};
3266 # disassemble columns
3268 if (my $cols = delete $attrs->{columns}) {
3269 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3270 if (ref $c eq 'HASH') {
3271 for my $as (keys %$c) {
3272 push @sel, $c->{$as};
3283 # when trying to weed off duplicates later do not go past this point -
3284 # everything added from here on is unbalanced "anyone's guess" stuff
3285 my $dedup_stop_idx = $#as;
3287 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3289 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3290 if $attrs->{select};
3292 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3293 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3295 # disqualify all $alias.col as-bits (inflate-map mandated)
3296 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3298 # de-duplicate the result (remove *identical* select/as pairs)
3299 # and also die on duplicate {as} pointing to different {select}s
3300 # not using a c-style for as the condition is prone to shrinkage
3303 while ($i <= $dedup_stop_idx) {
3304 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3309 elsif ($seen->{$as[$i]}++) {
3310 $self->throw_exception(
3311 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3319 $attrs->{select} = \@sel;
3320 $attrs->{as} = \@as;
3322 $attrs->{from} ||= [{
3324 -alias => $self->{attrs}{alias},
3325 $self->{attrs}{alias} => $source->from,
3328 if ( $attrs->{join} || $attrs->{prefetch} ) {
3330 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3331 if ref $attrs->{from} ne 'ARRAY';
3333 my $join = (delete $attrs->{join}) || {};
3335 if ( defined $attrs->{prefetch} ) {
3336 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3339 $attrs->{from} = # have to copy here to avoid corrupting the original
3341 @{ $attrs->{from} },
3342 $source->_resolve_join(
3345 { %{ $attrs->{seen_join} || {} } },
3346 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3347 ? $attrs->{from}[-1][0]{-join_path}
3354 if ( defined $attrs->{order_by} ) {
3355 $attrs->{order_by} = (
3356 ref( $attrs->{order_by} ) eq 'ARRAY'
3357 ? [ @{ $attrs->{order_by} } ]
3358 : [ $attrs->{order_by} || () ]
3362 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3363 $attrs->{group_by} = [ $attrs->{group_by} ];
3366 # generate the distinct induced group_by early, as prefetch will be carried via a
3367 # subquery (since a group_by is present)
3368 if (delete $attrs->{distinct}) {
3369 if ($attrs->{group_by}) {
3370 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3373 # distinct affects only the main selection part, not what prefetch may
3375 $attrs->{group_by} = $source->storage->_group_over_selection (
3383 # generate selections based on the prefetch helper
3385 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3386 if defined $attrs->{prefetch};
3390 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3391 if $attrs->{_dark_selector};
3393 $attrs->{collapse} = 1;
3395 # this is a separate structure (we don't look in {from} directly)
3396 # as the resolver needs to shift things off the lists to work
3397 # properly (identical-prefetches on different branches)
3399 if (ref $attrs->{from} eq 'ARRAY') {
3401 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3403 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3404 next unless $j->[0]{-alias};
3405 next unless $j->[0]{-join_path};
3406 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3408 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3411 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3412 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3416 my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map );
3418 # we need to somehow mark which columns came from prefetch
3420 my $sel_end = $#{$attrs->{select}};
3421 $attrs->{_prefetch_selector_range} = [ $sel_end + 1, $sel_end + @prefetch ];
3424 push @{ $attrs->{select} }, (map { $_->[0] } @prefetch);
3425 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
3428 # run through the resulting joinstructure (starting from our current slot)
3429 # and unset collapse if proven unnesessary
3430 if ($attrs->{collapse} && ref $attrs->{from} eq 'ARRAY') {
3432 if (@{$attrs->{from}} > 1) {
3434 # find where our table-spec starts and consider only things after us
3435 my @fromlist = @{$attrs->{from}};
3437 my $t = shift @fromlist;
3438 $t = $t->[0] if ref $t eq 'ARRAY'; #me vs join from-spec mismatch
3439 last if ($t->{-alias} && $t->{-alias} eq $alias);
3443 $attrs->{collapse} = ! $_->[0]{-is_single}
3448 # no joins - no collapse
3449 $attrs->{collapse} = 0;
3453 $attrs->{_single_object_inflation} = ! List::Util::first { $_ =~ /\./ } @{$attrs->{as}};
3455 # if both page and offset are specified, produce a combined offset
3456 # even though it doesn't make much sense, this is what pre 081xx has
3458 if (my $page = delete $attrs->{page}) {
3460 ($attrs->{rows} * ($page - 1))
3462 ($attrs->{offset} || 0)
3466 return $self->{_attrs} = $attrs;
3470 my ($self, $attr) = @_;
3472 if (ref $attr eq 'HASH') {
3473 return $self->_rollout_hash($attr);
3474 } elsif (ref $attr eq 'ARRAY') {
3475 return $self->_rollout_array($attr);
3481 sub _rollout_array {
3482 my ($self, $attr) = @_;
3485 foreach my $element (@{$attr}) {
3486 if (ref $element eq 'HASH') {
3487 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3488 } elsif (ref $element eq 'ARRAY') {
3489 # XXX - should probably recurse here
3490 push( @rolled_array, @{$self->_rollout_array($element)} );
3492 push( @rolled_array, $element );
3495 return \@rolled_array;
3499 my ($self, $attr) = @_;
3502 foreach my $key (keys %{$attr}) {
3503 push( @rolled_array, { $key => $attr->{$key} } );
3505 return \@rolled_array;
3508 sub _calculate_score {
3509 my ($self, $a, $b) = @_;
3511 if (defined $a xor defined $b) {
3514 elsif (not defined $a) {
3518 if (ref $b eq 'HASH') {
3519 my ($b_key) = keys %{$b};
3520 if (ref $a eq 'HASH') {
3521 my ($a_key) = keys %{$a};
3522 if ($a_key eq $b_key) {
3523 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3528 return ($a eq $b_key) ? 1 : 0;
3531 if (ref $a eq 'HASH') {
3532 my ($a_key) = keys %{$a};
3533 return ($b eq $a_key) ? 1 : 0;
3535 return ($b eq $a) ? 1 : 0;
3540 sub _merge_joinpref_attr {
3541 my ($self, $orig, $import) = @_;
3543 return $import unless defined($orig);
3544 return $orig unless defined($import);
3546 $orig = $self->_rollout_attr($orig);
3547 $import = $self->_rollout_attr($import);
3550 foreach my $import_element ( @{$import} ) {
3551 # find best candidate from $orig to merge $b_element into
3552 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3553 foreach my $orig_element ( @{$orig} ) {
3554 my $score = $self->_calculate_score( $orig_element, $import_element );
3555 if ($score > $best_candidate->{score}) {
3556 $best_candidate->{position} = $position;
3557 $best_candidate->{score} = $score;
3561 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3562 $import_key = '' if not defined $import_key;
3564 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3565 push( @{$orig}, $import_element );
3567 my $orig_best = $orig->[$best_candidate->{position}];
3568 # merge orig_best and b_element together and replace original with merged
3569 if (ref $orig_best ne 'HASH') {
3570 $orig->[$best_candidate->{position}] = $import_element;
3571 } elsif (ref $import_element eq 'HASH') {
3572 my ($key) = keys %{$orig_best};
3573 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3576 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3587 require Hash::Merge;
3588 my $hm = Hash::Merge->new;
3590 $hm->specify_behavior({
3593 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3595 if ($defl xor $defr) {
3596 return [ $defl ? $_[0] : $_[1] ];
3601 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3605 return [$_[0], $_[1]];
3609 return $_[1] if !defined $_[0];
3610 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3611 return [$_[0], @{$_[1]}]
3614 return [] if !defined $_[0] and !keys %{$_[1]};
3615 return [ $_[1] ] if !defined $_[0];
3616 return [ $_[0] ] if !keys %{$_[1]};
3617 return [$_[0], $_[1]]
3622 return $_[0] if !defined $_[1];
3623 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3624 return [@{$_[0]}, $_[1]]
3627 my @ret = @{$_[0]} or return $_[1];
3628 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3629 my %idx = map { $_ => 1 } @ret;
3630 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3634 return [ $_[1] ] if ! @{$_[0]};
3635 return $_[0] if !keys %{$_[1]};
3636 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3637 return [ @{$_[0]}, $_[1] ];
3642 return [] if !keys %{$_[0]} and !defined $_[1];
3643 return [ $_[0] ] if !defined $_[1];
3644 return [ $_[1] ] if !keys %{$_[0]};
3645 return [$_[0], $_[1]]
3648 return [] if !keys %{$_[0]} and !@{$_[1]};
3649 return [ $_[0] ] if !@{$_[1]};
3650 return $_[1] if !keys %{$_[0]};
3651 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3652 return [ $_[0], @{$_[1]} ];
3655 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3656 return [ $_[0] ] if !keys %{$_[1]};
3657 return [ $_[1] ] if !keys %{$_[0]};
3658 return [ $_[0] ] if $_[0] eq $_[1];
3659 return [ $_[0], $_[1] ];
3662 } => 'DBIC_RS_ATTR_MERGER');
3666 return $hm->merge ($_[1], $_[2]);
3670 sub STORABLE_freeze {
3671 my ($self, $cloning) = @_;
3672 my $to_serialize = { %$self };
3674 # A cursor in progress can't be serialized (and would make little sense anyway)
3675 delete $to_serialize->{cursor};
3677 # nor is it sensical to store a not-yet-fired-count pager
3678 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3679 delete $to_serialize->{pager};
3682 Storable::nfreeze($to_serialize);
3685 # need this hook for symmetry
3687 my ($self, $cloning, $serialized) = @_;
3689 %$self = %{ Storable::thaw($serialized) };
3695 =head2 throw_exception
3697 See L<DBIx::Class::Schema/throw_exception> for details.
3701 sub throw_exception {
3704 if (ref $self and my $rsrc = $self->result_source) {
3705 $rsrc->throw_exception(@_)
3708 DBIx::Class::Exception->throw(@_);
3712 # XXX: FIXME: Attributes docs need clearing up
3716 Attributes are used to refine a ResultSet in various ways when
3717 searching for data. They can be passed to any method which takes an
3718 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3721 These are in no particular order:
3727 =item Value: ( $order_by | \@order_by | \%order_by )
3731 Which column(s) to order the results by.
3733 [The full list of suitable values is documented in
3734 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3737 If a single column name, or an arrayref of names is supplied, the
3738 argument is passed through directly to SQL. The hashref syntax allows
3739 for connection-agnostic specification of ordering direction:
3741 For descending order:
3743 order_by => { -desc => [qw/col1 col2 col3/] }
3745 For explicit ascending order:
3747 order_by => { -asc => 'col' }
3749 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3750 supported, although you are strongly encouraged to use the hashref
3751 syntax as outlined above.
3757 =item Value: \@columns
3761 Shortcut to request a particular set of columns to be retrieved. Each
3762 column spec may be a string (a table column name), or a hash (in which
3763 case the key is the C<as> value, and the value is used as the C<select>
3764 expression). Adds C<me.> onto the start of any column without a C<.> in
3765 it and sets C<select> from that, then auto-populates C<as> from
3766 C<select> as normal. (You may also use the C<cols> attribute, as in
3767 earlier versions of DBIC.)
3769 Essentially C<columns> does the same as L</select> and L</as>.
3771 columns => [ 'foo', { bar => 'baz' } ]
3775 select => [qw/foo baz/],
3782 =item Value: \@columns
3786 Indicates additional columns to be selected from storage. Works the same
3787 as L</columns> but adds columns to the selection. (You may also use the
3788 C<include_columns> attribute, as in earlier versions of DBIC). For
3791 $schema->resultset('CD')->search(undef, {
3792 '+columns' => ['artist.name'],
3796 would return all CDs and include a 'name' column to the information
3797 passed to object inflation. Note that the 'artist' is the name of the
3798 column (or relationship) accessor, and 'name' is the name of the column
3799 accessor in the related table.
3801 B<NOTE:> You need to explicitly quote '+columns' when defining the attribute.
3802 Not doing so causes Perl to incorrectly interpret +columns as a bareword with a
3803 unary plus operator before it.
3805 =head2 include_columns
3809 =item Value: \@columns
3813 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3819 =item Value: \@select_columns
3823 Indicates which columns should be selected from the storage. You can use
3824 column names, or in the case of RDBMS back ends, function or stored procedure
3827 $rs = $schema->resultset('Employee')->search(undef, {
3830 { count => 'employeeid' },
3831 { max => { length => 'name' }, -as => 'longest_name' }
3836 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
3838 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
3839 use L</select>, to instruct DBIx::Class how to store the result of the column.
3840 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
3841 identifier aliasing. You can however alias a function, so you can use it in
3842 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
3843 attribute> supplied as shown in the example above.
3845 B<NOTE:> You need to explicitly quote '+select'/'+as' when defining the attributes.
3846 Not doing so causes Perl to incorrectly interpret them as a bareword with a
3847 unary plus operator before it.
3853 Indicates additional columns to be selected from storage. Works the same as
3854 L</select> but adds columns to the default selection, instead of specifying
3863 Indicates additional column names for those added via L</+select>. See L</as>.
3871 =item Value: \@inflation_names
3875 Indicates column names for object inflation. That is L</as> indicates the
3876 slot name in which the column value will be stored within the
3877 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
3878 identifier by the C<get_column> method (or via the object accessor B<if one
3879 with the same name already exists>) as shown below. The L</as> attribute has
3880 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
3882 $rs = $schema->resultset('Employee')->search(undef, {
3885 { count => 'employeeid' },
3886 { max => { length => 'name' }, -as => 'longest_name' }
3895 If the object against which the search is performed already has an accessor
3896 matching a column name specified in C<as>, the value can be retrieved using
3897 the accessor as normal:
3899 my $name = $employee->name();
3901 If on the other hand an accessor does not exist in the object, you need to
3902 use C<get_column> instead:
3904 my $employee_count = $employee->get_column('employee_count');
3906 You can create your own accessors if required - see
3907 L<DBIx::Class::Manual::Cookbook> for details.
3913 =item Value: ($rel_name | \@rel_names | \%rel_names)
3917 Contains a list of relationships that should be joined for this query. For
3920 # Get CDs by Nine Inch Nails
3921 my $rs = $schema->resultset('CD')->search(
3922 { 'artist.name' => 'Nine Inch Nails' },
3923 { join => 'artist' }
3926 Can also contain a hash reference to refer to the other relation's relations.
3929 package MyApp::Schema::Track;
3930 use base qw/DBIx::Class/;
3931 __PACKAGE__->table('track');
3932 __PACKAGE__->add_columns(qw/trackid cd position title/);
3933 __PACKAGE__->set_primary_key('trackid');
3934 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3937 # In your application
3938 my $rs = $schema->resultset('Artist')->search(
3939 { 'track.title' => 'Teardrop' },
3941 join => { cd => 'track' },
3942 order_by => 'artist.name',
3946 You need to use the relationship (not the table) name in conditions,
3947 because they are aliased as such. The current table is aliased as "me", so
3948 you need to use me.column_name in order to avoid ambiguity. For example:
3950 # Get CDs from 1984 with a 'Foo' track
3951 my $rs = $schema->resultset('CD')->search(
3954 'tracks.name' => 'Foo'
3956 { join => 'tracks' }
3959 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3960 similarly for a third time). For e.g.
3962 my $rs = $schema->resultset('Artist')->search({
3963 'cds.title' => 'Down to Earth',
3964 'cds_2.title' => 'Popular',
3966 join => [ qw/cds cds/ ],
3969 will return a set of all artists that have both a cd with title 'Down
3970 to Earth' and a cd with title 'Popular'.
3972 If you want to fetch related objects from other tables as well, see C<prefetch>
3975 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3981 =item Value: ($rel_name | \@rel_names | \%rel_names)
3985 Contains one or more relationships that should be fetched along with
3986 the main query (when they are accessed afterwards the data will
3987 already be available, without extra queries to the database). This is
3988 useful for when you know you will need the related objects, because it
3989 saves at least one query:
3991 my $rs = $schema->resultset('Tag')->search(
4000 The initial search results in SQL like the following:
4002 SELECT tag.*, cd.*, artist.* FROM tag
4003 JOIN cd ON tag.cd = cd.cdid
4004 JOIN artist ON cd.artist = artist.artistid
4006 L<DBIx::Class> has no need to go back to the database when we access the
4007 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4010 Simple prefetches will be joined automatically, so there is no need
4011 for a C<join> attribute in the above search.
4013 L</prefetch> can be used with the any of the relationship types and
4014 multiple prefetches can be specified together. Below is a more complex
4015 example that prefetches a CD's artist, its liner notes (if present),
4016 the cover image, the tracks on that cd, and the guests on those
4020 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4021 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4022 My::Schema::CD->has_one( cover_image => 'My::Schema::Artwork' );
4023 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4025 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4027 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4030 my $rs = $schema->resultset('CD')->search(
4034 { artist => 'record_label'}, # belongs_to => belongs_to
4035 'liner_note', # might_have
4036 'cover_image', # has_one
4037 { tracks => 'guests' }, # has_many => has_many
4042 This will produce SQL like the following:
4044 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4048 ON artist.artistid = me.artistid
4049 JOIN record_label record_label
4050 ON record_label.labelid = artist.labelid
4051 LEFT JOIN track tracks
4052 ON tracks.cdid = me.cdid
4053 LEFT JOIN guest guests
4054 ON guests.trackid = track.trackid
4055 LEFT JOIN liner_notes liner_note
4056 ON liner_note.cdid = me.cdid
4057 JOIN cd_artwork cover_image
4058 ON cover_image.cdid = me.cdid
4061 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4062 C<tracks>, and C<guests> of the CD will all be available through the
4063 relationship accessors without the need for additional queries to the
4066 However, there is one caveat to be observed: it can be dangerous to
4067 prefetch more than one L<has_many|DBIx::Class::Relationship/has_many>
4068 relationship on a given level. e.g.:
4070 my $rs = $schema->resultset('CD')->search(
4074 'tracks', # has_many
4075 { cd_to_producer => 'producer' }, # has_many => belongs_to (i.e. m2m)
4080 In fact, C<DBIx::Class> will emit the following warning:
4082 Prefetching multiple has_many rels tracks and cd_to_producer at top
4083 level will explode the number of row objects retrievable via ->next
4084 or ->all. Use at your own risk.
4086 The collapser currently can't identify duplicate tuples for multiple
4087 L<has_many|DBIx::Class::Relationship/has_many> relationships and as a
4088 result the second L<has_many|DBIx::Class::Relationship/has_many>
4089 relation could contain redundant objects.
4091 =head3 Using L</prefetch> with L</join>
4093 L</prefetch> implies a L</join> with the equivalent argument, and is
4094 properly merged with any existing L</join> specification. So the
4097 my $rs = $schema->resultset('CD')->search(
4098 {'record_label.name' => 'Music Product Ltd.'},
4100 join => {artist => 'record_label'},
4101 prefetch => 'artist',
4105 ... will work, searching on the record label's name, but only
4106 prefetching the C<artist>.
4108 =head3 Using L</prefetch> with L</select> / L</+select> / L</as> / L</+as>
4110 L</prefetch> implies a L</+select>/L</+as> with the fields of the
4111 prefetched relations. So given:
4113 my $rs = $schema->resultset('CD')->search(
4116 select => ['cd.title'],
4118 prefetch => 'artist',
4122 The L</select> becomes: C<'cd.title', 'artist.*'> and the L</as>
4123 becomes: C<'cd_title', 'artist.*'>.
4127 Prefetch does a lot of deep magic. As such, it may not behave exactly
4128 as you might expect.
4134 Prefetch uses the L</cache> to populate the prefetched relationships. This
4135 may or may not be what you want.
4139 If you specify a condition on a prefetched relationship, ONLY those
4140 rows that match the prefetched condition will be fetched into that relationship.
4141 This means that adding prefetch to a search() B<may alter> what is returned by
4142 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4144 my $artist_rs = $schema->resultset('Artist')->search({
4150 my $count = $artist_rs->first->cds->count;
4152 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4154 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4156 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4158 that cmp_ok() may or may not pass depending on the datasets involved. This
4159 behavior may or may not survive the 0.09 transition.
4171 Makes the resultset paged and specifies the page to retrieve. Effectively
4172 identical to creating a non-pages resultset and then calling ->page($page)
4175 If L</rows> attribute is not specified it defaults to 10 rows per page.
4177 When you have a paged resultset, L</count> will only return the number
4178 of rows in the page. To get the total, use the L</pager> and call
4179 C<total_entries> on it.
4189 Specifies the maximum number of rows for direct retrieval or the number of
4190 rows per page if the page attribute or method is used.
4196 =item Value: $offset
4200 Specifies the (zero-based) row number for the first row to be returned, or the
4201 of the first row of the first page if paging is used.
4203 =head2 software_limit
4207 =item Value: (0 | 1)
4211 When combined with L</rows> and/or L</offset> the generated SQL will not
4212 include any limit dialect stanzas. Instead the entire result will be selected
4213 as if no limits were specified, and DBIC will perform the limit locally, by
4214 artificially advancing and finishing the resulting L</cursor>.
4216 This is the recommended way of performing resultset limiting when no sane RDBMS
4217 implementation is available (e.g.
4218 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4219 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4225 =item Value: \@columns
4229 A arrayref of columns to group by. Can include columns of joined tables.
4231 group_by => [qw/ column1 column2 ... /]
4237 =item Value: $condition
4241 HAVING is a select statement attribute that is applied between GROUP BY and
4242 ORDER BY. It is applied to the after the grouping calculations have been
4245 having => { 'count_employee' => { '>=', 100 } }
4247 or with an in-place function in which case literal SQL is required:
4249 having => \[ 'count(employee) >= ?', [ count => 100 ] ]
4255 =item Value: (0 | 1)
4259 Set to 1 to group by all columns. If the resultset already has a group_by
4260 attribute, this setting is ignored and an appropriate warning is issued.
4266 Adds to the WHERE clause.
4268 # only return rows WHERE deleted IS NULL for all searches
4269 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
4271 Can be overridden by passing C<< { where => undef } >> as an attribute
4274 For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
4280 Set to 1 to cache search results. This prevents extra SQL queries if you
4281 revisit rows in your ResultSet:
4283 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4285 while( my $artist = $resultset->next ) {
4289 $rs->first; # without cache, this would issue a query
4291 By default, searches are not cached.
4293 For more examples of using these attributes, see
4294 L<DBIx::Class::Manual::Cookbook>.
4300 =item Value: ( 'update' | 'shared' )
4304 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT