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 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 some 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 aove, 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 $rsrc->_mk_row_parser({
1306 inflate_map => $attrs->{as},
1307 selection => $attrs->{select},
1308 collapse => $attrs->{collapse},
1309 unordered => $unordered,
1311 $rows, # modify in-place, shrinking/extending as necessary
1312 ($attrs->{collapse} and ! $fetch_all and ! $unordered)
1314 sub { my @r = $self->cursor->next or return undef; \@r },
1315 ($self->{stashed_rows} = []), # this is where we empty things and prepare for leftovers
1322 $_ = $res_class->$inflator($rsrc, @$_) for @$rows;
1325 if ($attrs->{record_filter}) {
1326 $_ = $attrs->{record_filter}->($_) for @$rows;
1332 =head2 result_source
1336 =item Arguments: $result_source?
1338 =item Return Value: $result_source
1342 An accessor for the primary ResultSource object from which this ResultSet
1349 =item Arguments: $result_class?
1351 =item Return Value: $result_class
1355 An accessor for the class to use when creating row objects. Defaults to
1356 C<< result_source->result_class >> - which in most cases is the name of the
1357 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1359 Note that changing the result_class will also remove any components
1360 that were originally loaded in the source class via
1361 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1362 in the original source class will not run.
1367 my ($self, $result_class) = @_;
1368 if ($result_class) {
1369 unless (ref $result_class) { # don't fire this for an object
1370 $self->ensure_class_loaded($result_class);
1372 $self->_result_class($result_class);
1373 # THIS LINE WOULD BE A BUG - this accessor specifically exists to
1374 # permit the user to set result class on one result set only; it only
1375 # chains if provided to search()
1376 #$self->{attrs}{result_class} = $result_class if ref $self;
1378 $self->_result_class;
1385 =item Arguments: $cond, \%attrs??
1387 =item Return Value: $count
1391 Performs an SQL C<COUNT> with the same query as the resultset was built
1392 with to find the number of elements. Passing arguments is equivalent to
1393 C<< $rs->search ($cond, \%attrs)->count >>
1399 return $self->search(@_)->count if @_ and defined $_[0];
1400 return scalar @{ $self->get_cache } if $self->get_cache;
1402 my $attrs = $self->_resolved_attrs_copy;
1404 # this is a little optimization - it is faster to do the limit
1405 # adjustments in software, instead of a subquery
1406 my $rows = delete $attrs->{rows};
1407 my $offset = delete $attrs->{offset};
1410 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1411 $crs = $self->_count_subq_rs ($attrs);
1414 $crs = $self->_count_rs ($attrs);
1416 my $count = $crs->next;
1418 $count -= $offset if $offset;
1419 $count = $rows if $rows and $rows < $count;
1420 $count = 0 if ($count < 0);
1429 =item Arguments: $cond, \%attrs??
1431 =item Return Value: $count_rs
1435 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1436 This can be very handy for subqueries:
1438 ->search( { amount => $some_rs->count_rs->as_query } )
1440 As with regular resultsets the SQL query will be executed only after
1441 the resultset is accessed via L</next> or L</all>. That would return
1442 the same single value obtainable via L</count>.
1448 return $self->search(@_)->count_rs if @_;
1450 # this may look like a lack of abstraction (count() does about the same)
1451 # but in fact an _rs *must* use a subquery for the limits, as the
1452 # software based limiting can not be ported if this $rs is to be used
1453 # in a subquery itself (i.e. ->as_query)
1454 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1455 return $self->_count_subq_rs;
1458 return $self->_count_rs;
1463 # returns a ResultSetColumn object tied to the count query
1466 my ($self, $attrs) = @_;
1468 my $rsrc = $self->result_source;
1469 $attrs ||= $self->_resolved_attrs;
1471 my $tmp_attrs = { %$attrs };
1472 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1473 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1475 # overwrite the selector (supplied by the storage)
1476 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $attrs);
1477 $tmp_attrs->{as} = 'count';
1478 delete @{$tmp_attrs}{qw/columns/};
1480 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1486 # same as above but uses a subquery
1488 sub _count_subq_rs {
1489 my ($self, $attrs) = @_;
1491 my $rsrc = $self->result_source;
1492 $attrs ||= $self->_resolved_attrs;
1494 my $sub_attrs = { %$attrs };
1495 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1496 delete @{$sub_attrs}{qw/collapse columns as select _prefetch_selector_range order_by for/};
1498 # if we multi-prefetch we group_by something unique, as this is what we would
1499 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1500 if ( $attrs->{collapse} ) {
1501 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1502 $rsrc->_identifying_column_set || $self->throw_exception(
1503 'Unable to construct a unique group_by criteria properly collapsing the '
1504 . 'has_many prefetch before count()'
1509 # Calculate subquery selector
1510 if (my $g = $sub_attrs->{group_by}) {
1512 my $sql_maker = $rsrc->storage->sql_maker;
1514 # necessary as the group_by may refer to aliased functions
1516 for my $sel (@{$attrs->{select}}) {
1517 $sel_index->{$sel->{-as}} = $sel
1518 if (ref $sel eq 'HASH' and $sel->{-as});
1521 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1522 # also look for named aggregates referred in the having clause
1523 # having often contains scalarrefs - thus parse it out entirely
1525 if ($attrs->{having}) {
1526 local $sql_maker->{having_bind};
1527 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1528 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1529 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1530 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1531 # if we don't unset it we screw up retarded but unfortunately working
1532 # 'MAX(foo.bar)' => { '>', 3 }
1533 $sql_maker->{name_sep} = '';
1536 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1538 my $sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1540 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1541 # and if all fails for an utterly naive quoted scalar-with-function
1543 $rquote $sep $lquote (.+?) $rquote
1545 [\s,] \w+ \. (\w+) [\s,]
1547 [\s,] $lquote (.+?) $rquote [\s,]
1549 push @parts, ($1 || $2 || $3); # one of them matched if we got here
1554 my $colpiece = $sel_index->{$_} || $_;
1556 # unqualify join-based group_by's. Arcane but possible query
1557 # also horrible horrible hack to alias a column (not a func.)
1558 # (probably need to introduce SQLA syntax)
1559 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1562 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1564 push @{$sub_attrs->{select}}, $colpiece;
1568 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1569 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1572 return $rsrc->resultset_class
1573 ->new ($rsrc, $sub_attrs)
1575 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1576 ->get_column ('count');
1583 =head2 count_literal
1587 =item Arguments: $sql_fragment, @bind_values
1589 =item Return Value: $count
1593 Counts the results in a literal query. Equivalent to calling L</search_literal>
1594 with the passed arguments, then L</count>.
1598 sub count_literal { shift->search_literal(@_)->count; }
1604 =item Arguments: none
1606 =item Return Value: @objects
1610 Returns all elements in the resultset.
1617 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1620 delete $self->{stashed_rows};
1621 delete $self->{stashed_objects};
1623 if (my $c = $self->get_cache) {
1627 $self->cursor->reset;
1629 my $objs = $self->_construct_objects(undef, 'fetch_all') || [];
1631 $self->set_cache($objs) if $self->{attrs}{cache};
1640 =item Arguments: none
1642 =item Return Value: $self
1646 Resets the resultset's cursor, so you can iterate through the elements again.
1647 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1654 delete $self->{_attrs};
1655 delete $self->{stashed_rows};
1656 delete $self->{stashed_objects};
1658 $self->{all_cache_position} = 0;
1659 $self->cursor->reset;
1667 =item Arguments: none
1669 =item Return Value: $object | undef
1673 Resets the resultset and returns an object for the first result (or C<undef>
1674 if the resultset is empty).
1679 return $_[0]->reset->next;
1685 # Determines whether and what type of subquery is required for the $rs operation.
1686 # If grouping is necessary either supplies its own, or verifies the current one
1687 # After all is done delegates to the proper storage method.
1689 sub _rs_update_delete {
1690 my ($self, $op, $values) = @_;
1692 my $cond = $self->{cond};
1693 my $rsrc = $self->result_source;
1694 my $storage = $rsrc->schema->storage;
1696 my $attrs = { %{$self->_resolved_attrs} };
1698 # "needs" is a strong word here - if the subquery is part of an IN clause - no point of
1699 # even adding the group_by. It will really be used only when composing a poor-man's
1700 # multicolumn-IN equivalent OR set
1701 my $needs_group_by_subq = defined $attrs->{group_by};
1703 # simplify the joinmap and maybe decide if a grouping (and thus subquery) is necessary
1704 my $relation_classifications;
1705 if (ref($attrs->{from}) eq 'ARRAY') {
1706 $attrs->{from} = $storage->_prune_unused_joins ($attrs->{from}, $attrs->{select}, $cond, $attrs);
1708 $relation_classifications = $storage->_resolve_aliastypes_from_select_args (
1709 [ @{$attrs->{from}}[1 .. $#{$attrs->{from}}] ],
1713 ) unless $needs_group_by_subq; # we already know we need a group, no point of resolving them
1716 $needs_group_by_subq ||= 1; # if {from} is unparseable assume the worst
1719 $needs_group_by_subq ||= exists $relation_classifications->{multiplying};
1721 # if no subquery - life is easy-ish
1723 $needs_group_by_subq
1725 keys %$relation_classifications # if any joins at all - need to wrap a subq
1727 $self->_has_resolved_attr(qw/rows offset/) # limits call for a subq
1729 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1730 # a condition containing 'me' or other table prefixes will not work
1731 # at all. What this code tries to do (badly) is to generate a condition
1732 # with the qualifiers removed, by exploiting the quote mechanism of sqla
1734 # this is atrocious and should be replaced by normal sqla introspection
1736 my ($sql, @bind) = do {
1737 my $sqla = $rsrc->storage->sql_maker;
1738 local $sqla->{_dequalify_idents} = 1;
1739 $sqla->_recurse_where($self->{cond});
1742 return $rsrc->storage->$op(
1744 $op eq 'update' ? $values : (),
1745 $self->{cond} ? \[$sql, @bind] : (),
1749 # we got this far - means it is time to wrap a subquery
1750 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1752 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1757 my $existing_group_by = delete $attrs->{group_by};
1759 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1760 delete $attrs->{$_} for qw/collapse select _prefetch_selector_range as/;
1761 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1762 $attrs->{group_by} = \ ''; # FIXME - this is an evil hack, it causes the optimiser to kick in and throw away the LEFT joins
1763 my $subrs = (ref $self)->new($rsrc, $attrs);
1765 if (@$idcols == 1) {
1766 return $storage->$op (
1768 $op eq 'update' ? $values : (),
1769 { $idcols->[0] => { -in => $subrs->as_query } },
1772 elsif ($storage->_use_multicolumn_in) {
1773 # This is hideously ugly, but SQLA does not understand multicol IN expressions
1774 my $sql_maker = $storage->sql_maker;
1775 my ($sql, @bind) = @${$subrs->as_query};
1776 $sql = sprintf ('(%s) IN %s', # the as_query already comes with a set of parenthesis
1777 join (', ', map { $sql_maker->_quote ($_) } @$idcols),
1781 return $storage->$op (
1783 $op eq 'update' ? $values : (),
1788 # if all else fails - get all primary keys and operate over a ORed set
1789 # wrap in a transaction for consistency
1790 # this is where the group_by starts to matter
1792 if ($needs_group_by_subq) {
1793 $subq_group_by = $attrs->{columns};
1795 # make sure if there is a supplied group_by it matches the columns compiled above
1796 # perfectly. Anything else can not be sanely executed on most databases so croak
1797 # right then and there
1798 if ($existing_group_by) {
1799 my @current_group_by = map
1800 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1805 join ("\x00", sort @current_group_by)
1807 join ("\x00", sort @$subq_group_by )
1809 $self->throw_exception (
1810 "You have just attempted a $op operation on a resultset which does group_by"
1811 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1812 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1813 . ' kind of queries. Please retry the operation with a modified group_by or'
1814 . ' without using one at all.'
1820 my $guard = $storage->txn_scope_guard;
1823 for my $row ($subrs->search({}, { group_by => $subq_group_by })->cursor->all) {
1824 push @op_condition, { map
1825 { $idcols->[$_] => $row->[$_] }
1830 my $res = $storage->$op (
1832 $op eq 'update' ? $values : (),
1846 =item Arguments: \%values
1848 =item Return Value: $storage_rv
1852 Sets the specified columns in the resultset to the supplied values in a
1853 single query. Note that this will not run any accessor/set_column/update
1854 triggers, nor will it update any row object instances derived from this
1855 resultset (this includes the contents of the L<resultset cache|/set_cache>
1856 if any). See L</update_all> if you need to execute any on-update
1857 triggers or cascades defined either by you or a
1858 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1860 The return value is a pass through of what the underlying
1861 storage backend returned, and may vary. See L<DBI/execute> for the most
1866 Note that L</update> does not process/deflate any of the values passed in.
1867 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
1868 ensure manually that any value passed to this method will stringify to
1869 something the RDBMS knows how to deal with. A notable example is the
1870 handling of L<DateTime> objects, for more info see:
1871 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
1876 my ($self, $values) = @_;
1877 $self->throw_exception('Values for update must be a hash')
1878 unless ref $values eq 'HASH';
1880 return $self->_rs_update_delete ('update', $values);
1887 =item Arguments: \%values
1889 =item Return Value: 1
1893 Fetches all objects and updates them one at a time via
1894 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
1895 triggers, while L</update> will not.
1900 my ($self, $values) = @_;
1901 $self->throw_exception('Values for update_all must be a hash')
1902 unless ref $values eq 'HASH';
1904 my $guard = $self->result_source->schema->txn_scope_guard;
1905 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
1914 =item Arguments: none
1916 =item Return Value: $storage_rv
1920 Deletes the rows matching this resultset in a single query. Note that this
1921 will not run any delete triggers, nor will it alter the
1922 L<in_storage|DBIx::Class::Row/in_storage> status of any row object instances
1923 derived from this resultset (this includes the contents of the
1924 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
1925 execute any on-delete triggers or cascades defined either by you or a
1926 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1928 The return value is a pass through of what the underlying storage backend
1929 returned, and may vary. See L<DBI/execute> for the most common case.
1935 $self->throw_exception('delete does not accept any arguments')
1938 return $self->_rs_update_delete ('delete');
1945 =item Arguments: none
1947 =item Return Value: 1
1951 Fetches all objects and deletes them one at a time via
1952 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
1953 triggers, while L</delete> will not.
1959 $self->throw_exception('delete_all does not accept any arguments')
1962 my $guard = $self->result_source->schema->txn_scope_guard;
1963 $_->delete for $self->all;
1972 =item Arguments: \@data;
1976 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1977 For the arrayref of hashrefs style each hashref should be a structure suitable
1978 for submitting to a $resultset->create(...) method.
1980 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1981 to insert the data, as this is a faster method.
1983 Otherwise, each set of data is inserted into the database using
1984 L<DBIx::Class::ResultSet/create>, and the resulting objects are
1985 accumulated into an array. The array itself, or an array reference
1986 is returned depending on scalar or list context.
1988 Example: Assuming an Artist Class that has many CDs Classes relating:
1990 my $Artist_rs = $schema->resultset("Artist");
1992 ## Void Context Example
1993 $Artist_rs->populate([
1994 { artistid => 4, name => 'Manufactured Crap', cds => [
1995 { title => 'My First CD', year => 2006 },
1996 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1999 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2000 { title => 'My parents sold me to a record company', year => 2005 },
2001 { title => 'Why Am I So Ugly?', year => 2006 },
2002 { title => 'I Got Surgery and am now Popular', year => 2007 }
2007 ## Array Context Example
2008 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
2009 { name => "Artist One"},
2010 { name => "Artist Two"},
2011 { name => "Artist Three", cds=> [
2012 { title => "First CD", year => 2007},
2013 { title => "Second CD", year => 2008},
2017 print $ArtistOne->name; ## response is 'Artist One'
2018 print $ArtistThree->cds->count ## reponse is '2'
2020 For the arrayref of arrayrefs style, the first element should be a list of the
2021 fieldsnames to which the remaining elements are rows being inserted. For
2024 $Arstist_rs->populate([
2025 [qw/artistid name/],
2026 [100, 'A Formally Unknown Singer'],
2027 [101, 'A singer that jumped the shark two albums ago'],
2028 [102, 'An actually cool singer'],
2031 Please note an important effect on your data when choosing between void and
2032 wantarray context. Since void context goes straight to C<insert_bulk> in
2033 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
2034 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
2035 create primary keys for you, you will find that your PKs are empty. In this
2036 case you will have to use the wantarray context in order to create those
2044 # cruft placed in standalone method
2045 my $data = $self->_normalize_populate_args(@_);
2047 return unless @$data;
2049 if(defined wantarray) {
2051 foreach my $item (@$data) {
2052 push(@created, $self->create($item));
2054 return wantarray ? @created : \@created;
2057 my $first = $data->[0];
2059 # if a column is a registered relationship, and is a non-blessed hash/array, consider
2060 # it relationship data
2061 my (@rels, @columns);
2062 my $rsrc = $self->result_source;
2063 my $rels = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2064 for (keys %$first) {
2065 my $ref = ref $first->{$_};
2066 $rels->{$_} && ($ref eq 'ARRAY' or $ref eq 'HASH')
2072 my @pks = $rsrc->primary_columns;
2074 ## do the belongs_to relationships
2075 foreach my $index (0..$#$data) {
2077 # delegate to create() for any dataset without primary keys with specified relationships
2078 if (grep { !defined $data->[$index]->{$_} } @pks ) {
2080 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
2081 my @ret = $self->populate($data);
2087 foreach my $rel (@rels) {
2088 next unless ref $data->[$index]->{$rel} eq "HASH";
2089 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
2090 my ($reverse_relname, $reverse_relinfo) = %{$rsrc->reverse_relationship_info($rel)};
2091 my $related = $result->result_source->_resolve_condition(
2092 $reverse_relinfo->{cond},
2098 delete $data->[$index]->{$rel};
2099 $data->[$index] = {%{$data->[$index]}, %$related};
2101 push @columns, keys %$related if $index == 0;
2105 ## inherit the data locked in the conditions of the resultset
2106 my ($rs_data) = $self->_merge_with_rscond({});
2107 delete @{$rs_data}{@columns};
2108 my @inherit_cols = keys %$rs_data;
2109 my @inherit_data = values %$rs_data;
2111 ## do bulk insert on current row
2112 $rsrc->storage->insert_bulk(
2114 [@columns, @inherit_cols],
2115 [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
2118 ## do the has_many relationships
2119 foreach my $item (@$data) {
2123 foreach my $rel (@rels) {
2124 next unless ref $item->{$rel} eq "ARRAY" && @{ $item->{$rel} };
2126 $main_row ||= $self->new_result({map { $_ => $item->{$_} } @pks});
2128 my $child = $main_row->$rel;
2130 my $related = $child->result_source->_resolve_condition(
2131 $rels->{$rel}{cond},
2137 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
2138 my @populate = map { {%$_, %$related} } @rows_to_add;
2140 $child->populate( \@populate );
2147 # populate() argumnets went over several incarnations
2148 # What we ultimately support is AoH
2149 sub _normalize_populate_args {
2150 my ($self, $arg) = @_;
2152 if (ref $arg eq 'ARRAY') {
2156 elsif (ref $arg->[0] eq 'HASH') {
2159 elsif (ref $arg->[0] eq 'ARRAY') {
2161 my @colnames = @{$arg->[0]};
2162 foreach my $values (@{$arg}[1 .. $#$arg]) {
2163 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
2169 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2176 =item Arguments: none
2178 =item Return Value: $pager
2182 Return Value a L<Data::Page> object for the current resultset. Only makes
2183 sense for queries with a C<page> attribute.
2185 To get the full count of entries for a paged resultset, call
2186 C<total_entries> on the L<Data::Page> object.
2193 return $self->{pager} if $self->{pager};
2195 my $attrs = $self->{attrs};
2196 if (!defined $attrs->{page}) {
2197 $self->throw_exception("Can't create pager for non-paged rs");
2199 elsif ($attrs->{page} <= 0) {
2200 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2202 $attrs->{rows} ||= 10;
2204 # throw away the paging flags and re-run the count (possibly
2205 # with a subselect) to get the real total count
2206 my $count_attrs = { %$attrs };
2207 delete $count_attrs->{$_} for qw/rows offset page pager/;
2209 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2211 require DBIx::Class::ResultSet::Pager;
2212 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2213 sub { $total_rs->count }, #lazy-get the total
2215 $self->{attrs}{page},
2223 =item Arguments: $page_number
2225 =item Return Value: $rs
2229 Returns a resultset for the $page_number page of the resultset on which page
2230 is called, where each page contains a number of rows equal to the 'rows'
2231 attribute set on the resultset (10 by default).
2236 my ($self, $page) = @_;
2237 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2244 =item Arguments: \%vals
2246 =item Return Value: $rowobject
2250 Creates a new row object in the resultset's result class and returns
2251 it. The row is not inserted into the database at this point, call
2252 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2253 will tell you whether the row object has been inserted or not.
2255 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2260 my ($self, $values) = @_;
2261 $self->throw_exception( "new_result needs a hash" )
2262 unless (ref $values eq 'HASH');
2264 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2268 @$cols_from_relations
2269 ? (-cols_from_relations => $cols_from_relations)
2271 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2274 return $self->result_class->new(\%new);
2277 # _merge_with_rscond
2279 # Takes a simple hash of K/V data and returns its copy merged with the
2280 # condition already present on the resultset. Additionally returns an
2281 # arrayref of value/condition names, which were inferred from related
2282 # objects (this is needed for in-memory related objects)
2283 sub _merge_with_rscond {
2284 my ($self, $data) = @_;
2286 my (%new_data, @cols_from_relations);
2288 my $alias = $self->{attrs}{alias};
2290 if (! defined $self->{cond}) {
2291 # just massage $data below
2293 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
2294 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
2295 @cols_from_relations = keys %new_data;
2297 elsif (ref $self->{cond} ne 'HASH') {
2298 $self->throw_exception(
2299 "Can't abstract implicit construct, resultset condition not a hash"
2303 # precendence must be given to passed values over values inherited from
2304 # the cond, so the order here is important.
2305 my $collapsed_cond = $self->_collapse_cond($self->{cond});
2306 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
2308 while ( my($col, $value) = each %implied ) {
2309 my $vref = ref $value;
2315 (keys %$value)[0] eq '='
2317 $new_data{$col} = $value->{'='};
2319 elsif( !$vref or $vref eq 'SCALAR' or blessed($value) ) {
2320 $new_data{$col} = $value;
2327 %{ $self->_remove_alias($data, $alias) },
2330 return (\%new_data, \@cols_from_relations);
2333 # _has_resolved_attr
2335 # determines if the resultset defines at least one
2336 # of the attributes supplied
2338 # used to determine if a subquery is neccessary
2340 # supports some virtual attributes:
2342 # This will scan for any joins being present on the resultset.
2343 # It is not a mere key-search but a deep inspection of {from}
2346 sub _has_resolved_attr {
2347 my ($self, @attr_names) = @_;
2349 my $attrs = $self->_resolved_attrs;
2353 for my $n (@attr_names) {
2354 if (grep { $n eq $_ } (qw/-join/) ) {
2355 $extra_checks{$n}++;
2359 my $attr = $attrs->{$n};
2361 next if not defined $attr;
2363 if (ref $attr eq 'HASH') {
2364 return 1 if keys %$attr;
2366 elsif (ref $attr eq 'ARRAY') {
2374 # a resolved join is expressed as a multi-level from
2376 $extra_checks{-join}
2378 ref $attrs->{from} eq 'ARRAY'
2380 @{$attrs->{from}} > 1
2388 # Recursively collapse the condition.
2390 sub _collapse_cond {
2391 my ($self, $cond, $collapsed) = @_;
2395 if (ref $cond eq 'ARRAY') {
2396 foreach my $subcond (@$cond) {
2397 next unless ref $subcond; # -or
2398 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2401 elsif (ref $cond eq 'HASH') {
2402 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2403 foreach my $subcond (@{$cond->{-and}}) {
2404 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2408 foreach my $col (keys %$cond) {
2409 my $value = $cond->{$col};
2410 $collapsed->{$col} = $value;
2420 # Remove the specified alias from the specified query hash. A copy is made so
2421 # the original query is not modified.
2424 my ($self, $query, $alias) = @_;
2426 my %orig = %{ $query || {} };
2429 foreach my $key (keys %orig) {
2431 $unaliased{$key} = $orig{$key};
2434 $unaliased{$1} = $orig{$key}
2435 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2445 =item Arguments: none
2447 =item Return Value: \[ $sql, @bind ]
2451 Returns the SQL query and bind vars associated with the invocant.
2453 This is generally used as the RHS for a subquery.
2460 my $attrs = $self->_resolved_attrs_copy;
2465 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2466 # $sql also has no wrapping parenthesis in list ctx
2468 my $sqlbind = $self->result_source->storage
2469 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2478 =item Arguments: \%vals, \%attrs?
2480 =item Return Value: $rowobject
2484 my $artist = $schema->resultset('Artist')->find_or_new(
2485 { artist => 'fred' }, { key => 'artists' });
2487 $cd->cd_to_producer->find_or_new({ producer => $producer },
2488 { key => 'primary });
2490 Find an existing record from this resultset using L</find>. if none exists,
2491 instantiate a new result object and return it. The object will not be saved
2492 into your storage until you call L<DBIx::Class::Row/insert> on it.
2494 You most likely want this method when looking for existing rows using a unique
2495 constraint that is not the primary key, or looking for related rows.
2497 If you want objects to be saved immediately, use L</find_or_create> instead.
2499 B<Note>: Make sure to read the documentation of L</find> and understand the
2500 significance of the C<key> attribute, as its lack may skew your search, and
2501 subsequently result in spurious new objects.
2503 B<Note>: Take care when using C<find_or_new> with a table having
2504 columns with default values that you intend to be automatically
2505 supplied by the database (e.g. an auto_increment primary key column).
2506 In normal usage, the value of such columns should NOT be included at
2507 all in the call to C<find_or_new>, even when set to C<undef>.
2513 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2514 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2515 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2518 return $self->new_result($hash);
2525 =item Arguments: \%vals
2527 =item Return Value: a L<DBIx::Class::Row> $object
2531 Attempt to create a single new row or a row with multiple related rows
2532 in the table represented by the resultset (and related tables). This
2533 will not check for duplicate rows before inserting, use
2534 L</find_or_create> to do that.
2536 To create one row for this resultset, pass a hashref of key/value
2537 pairs representing the columns of the table and the values you wish to
2538 store. If the appropriate relationships are set up, foreign key fields
2539 can also be passed an object representing the foreign row, and the
2540 value will be set to its primary key.
2542 To create related objects, pass a hashref of related-object column values
2543 B<keyed on the relationship name>. If the relationship is of type C<multi>
2544 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2545 The process will correctly identify columns holding foreign keys, and will
2546 transparently populate them from the keys of the corresponding relation.
2547 This can be applied recursively, and will work correctly for a structure
2548 with an arbitrary depth and width, as long as the relationships actually
2549 exists and the correct column data has been supplied.
2552 Instead of hashrefs of plain related data (key/value pairs), you may
2553 also pass new or inserted objects. New objects (not inserted yet, see
2554 L</new>), will be inserted into their appropriate tables.
2556 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2558 Example of creating a new row.
2560 $person_rs->create({
2561 name=>"Some Person",
2562 email=>"somebody@someplace.com"
2565 Example of creating a new row and also creating rows in a related C<has_many>
2566 or C<has_one> resultset. Note Arrayref.
2569 { artistid => 4, name => 'Manufactured Crap', cds => [
2570 { title => 'My First CD', year => 2006 },
2571 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2576 Example of creating a new row and also creating a row in a related
2577 C<belongs_to> resultset. Note Hashref.
2580 title=>"Music for Silly Walks",
2583 name=>"Silly Musician",
2591 When subclassing ResultSet never attempt to override this method. Since
2592 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2593 lot of the internals simply never call it, so your override will be
2594 bypassed more often than not. Override either L<new|DBIx::Class::Row/new>
2595 or L<insert|DBIx::Class::Row/insert> depending on how early in the
2596 L</create> process you need to intervene.
2603 my ($self, $attrs) = @_;
2604 $self->throw_exception( "create needs a hashref" )
2605 unless ref $attrs eq 'HASH';
2606 return $self->new_result($attrs)->insert;
2609 =head2 find_or_create
2613 =item Arguments: \%vals, \%attrs?
2615 =item Return Value: $rowobject
2619 $cd->cd_to_producer->find_or_create({ producer => $producer },
2620 { key => 'primary' });
2622 Tries to find a record based on its primary key or unique constraints; if none
2623 is found, creates one and returns that instead.
2625 my $cd = $schema->resultset('CD')->find_or_create({
2627 artist => 'Massive Attack',
2628 title => 'Mezzanine',
2632 Also takes an optional C<key> attribute, to search by a specific key or unique
2633 constraint. For example:
2635 my $cd = $schema->resultset('CD')->find_or_create(
2637 artist => 'Massive Attack',
2638 title => 'Mezzanine',
2640 { key => 'cd_artist_title' }
2643 B<Note>: Make sure to read the documentation of L</find> and understand the
2644 significance of the C<key> attribute, as its lack may skew your search, and
2645 subsequently result in spurious row creation.
2647 B<Note>: Because find_or_create() reads from the database and then
2648 possibly inserts based on the result, this method is subject to a race
2649 condition. Another process could create a record in the table after
2650 the find has completed and before the create has started. To avoid
2651 this problem, use find_or_create() inside a transaction.
2653 B<Note>: Take care when using C<find_or_create> with a table having
2654 columns with default values that you intend to be automatically
2655 supplied by the database (e.g. an auto_increment primary key column).
2656 In normal usage, the value of such columns should NOT be included at
2657 all in the call to C<find_or_create>, even when set to C<undef>.
2659 See also L</find> and L</update_or_create>. For information on how to declare
2660 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2662 If you need to know if an existing row was found or a new one created use
2663 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2664 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2667 my $cd = $schema->resultset('CD')->find_or_new({
2669 artist => 'Massive Attack',
2670 title => 'Mezzanine',
2674 if( $cd->in_storage ) {
2681 sub find_or_create {
2683 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2684 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2685 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2688 return $self->create($hash);
2691 =head2 update_or_create
2695 =item Arguments: \%col_values, { key => $unique_constraint }?
2697 =item Return Value: $row_object
2701 $resultset->update_or_create({ col => $val, ... });
2703 Like L</find_or_create>, but if a row is found it is immediately updated via
2704 C<< $found_row->update (\%col_values) >>.
2707 Takes an optional C<key> attribute to search on a specific unique constraint.
2710 # In your application
2711 my $cd = $schema->resultset('CD')->update_or_create(
2713 artist => 'Massive Attack',
2714 title => 'Mezzanine',
2717 { key => 'cd_artist_title' }
2720 $cd->cd_to_producer->update_or_create({
2721 producer => $producer,
2727 B<Note>: Make sure to read the documentation of L</find> and understand the
2728 significance of the C<key> attribute, as its lack may skew your search, and
2729 subsequently result in spurious row creation.
2731 B<Note>: Take care when using C<update_or_create> with a table having
2732 columns with default values that you intend to be automatically
2733 supplied by the database (e.g. an auto_increment primary key column).
2734 In normal usage, the value of such columns should NOT be included at
2735 all in the call to C<update_or_create>, even when set to C<undef>.
2737 See also L</find> and L</find_or_create>. For information on how to declare
2738 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2740 If you need to know if an existing row was updated or a new one created use
2741 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2742 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2745 my $cd = $schema->resultset('CD')->update_or_new(
2747 artist => 'Massive Attack',
2748 title => 'Mezzanine',
2751 { key => 'cd_artist_title' }
2754 if( $cd->in_storage ) {
2761 sub update_or_create {
2763 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2764 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2766 my $row = $self->find($cond, $attrs);
2768 $row->update($cond);
2772 return $self->create($cond);
2775 =head2 update_or_new
2779 =item Arguments: \%col_values, { key => $unique_constraint }?
2781 =item Return Value: $rowobject
2785 $resultset->update_or_new({ col => $val, ... });
2787 Like L</find_or_new> but if a row is found it is immediately updated via
2788 C<< $found_row->update (\%col_values) >>.
2792 # In your application
2793 my $cd = $schema->resultset('CD')->update_or_new(
2795 artist => 'Massive Attack',
2796 title => 'Mezzanine',
2799 { key => 'cd_artist_title' }
2802 if ($cd->in_storage) {
2803 # the cd was updated
2806 # the cd is not yet in the database, let's insert it
2810 B<Note>: Make sure to read the documentation of L</find> and understand the
2811 significance of the C<key> attribute, as its lack may skew your search, and
2812 subsequently result in spurious new objects.
2814 B<Note>: Take care when using C<update_or_new> with a table having
2815 columns with default values that you intend to be automatically
2816 supplied by the database (e.g. an auto_increment primary key column).
2817 In normal usage, the value of such columns should NOT be included at
2818 all in the call to C<update_or_new>, even when set to C<undef>.
2820 See also L</find>, L</find_or_create> and L</find_or_new>.
2826 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2827 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2829 my $row = $self->find( $cond, $attrs );
2830 if ( defined $row ) {
2831 $row->update($cond);
2835 return $self->new_result($cond);
2842 =item Arguments: none
2844 =item Return Value: \@cache_objects | undef
2848 Gets the contents of the cache for the resultset, if the cache is set.
2850 The cache is populated either by using the L</prefetch> attribute to
2851 L</search> or by calling L</set_cache>.
2863 =item Arguments: \@cache_objects
2865 =item Return Value: \@cache_objects
2869 Sets the contents of the cache for the resultset. Expects an arrayref
2870 of objects of the same class as those produced by the resultset. Note that
2871 if the cache is set the resultset will return the cached objects rather
2872 than re-querying the database even if the cache attr is not set.
2874 The contents of the cache can also be populated by using the
2875 L</prefetch> attribute to L</search>.
2880 my ( $self, $data ) = @_;
2881 $self->throw_exception("set_cache requires an arrayref")
2882 if defined($data) && (ref $data ne 'ARRAY');
2883 $self->{all_cache} = $data;
2890 =item Arguments: none
2892 =item Return Value: undef
2896 Clears the cache for the resultset.
2901 shift->set_cache(undef);
2908 =item Arguments: none
2910 =item Return Value: true, if the resultset has been paginated
2918 return !!$self->{attrs}{page};
2925 =item Arguments: none
2927 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2935 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
2938 =head2 related_resultset
2942 =item Arguments: $relationship_name
2944 =item Return Value: $resultset
2948 Returns a related resultset for the supplied relationship name.
2950 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2954 sub related_resultset {
2955 my ($self, $rel) = @_;
2957 $self->{related_resultsets} ||= {};
2958 return $self->{related_resultsets}{$rel} ||= do {
2959 my $rsrc = $self->result_source;
2960 my $rel_info = $rsrc->relationship_info($rel);
2962 $self->throw_exception(
2963 "search_related: result source '" . $rsrc->source_name .
2964 "' has no such relationship $rel")
2967 my $attrs = $self->_chain_relationship($rel);
2969 my $join_count = $attrs->{seen_join}{$rel};
2971 my $alias = $self->result_source->storage
2972 ->relname_to_table_alias($rel, $join_count);
2974 # since this is search_related, and we already slid the select window inwards
2975 # (the select/as attrs were deleted in the beginning), we need to flip all
2976 # left joins to inner, so we get the expected results
2977 # read the comment on top of the actual function to see what this does
2978 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
2981 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2982 delete @{$attrs}{qw(result_class alias)};
2986 if (my $cache = $self->get_cache) {
2987 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2988 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache||[]} }
2993 my $rel_source = $rsrc->related_source($rel);
2997 # The reason we do this now instead of passing the alias to the
2998 # search_rs below is that if you wrap/overload resultset on the
2999 # source you need to know what alias it's -going- to have for things
3000 # to work sanely (e.g. RestrictWithObject wants to be able to add
3001 # extra query restrictions, and these may need to be $alias.)
3003 my $rel_attrs = $rel_source->resultset_attributes;
3004 local $rel_attrs->{alias} = $alias;
3006 $rel_source->resultset
3010 where => $attrs->{where},
3013 $new->set_cache($new_cache) if $new_cache;
3018 =head2 current_source_alias
3022 =item Arguments: none
3024 =item Return Value: $source_alias
3028 Returns the current table alias for the result source this resultset is built
3029 on, that will be used in the SQL query. Usually it is C<me>.
3031 Currently the source alias that refers to the result set returned by a
3032 L</search>/L</find> family method depends on how you got to the resultset: it's
3033 C<me> by default, but eg. L</search_related> aliases it to the related result
3034 source name (and keeps C<me> referring to the original result set). The long
3035 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3036 (and make this method unnecessary).
3038 Thus it's currently necessary to use this method in predefined queries (see
3039 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3040 source alias of the current result set:
3042 # in a result set class
3044 my ($self, $user) = @_;
3046 my $me = $self->current_source_alias;
3048 return $self->search({
3049 "$me.modified" => $user->id,
3055 sub current_source_alias {
3058 return ($self->{attrs} || {})->{alias} || 'me';
3061 =head2 as_subselect_rs
3065 =item Arguments: none
3067 =item Return Value: $resultset
3071 Act as a barrier to SQL symbols. The resultset provided will be made into a
3072 "virtual view" by including it as a subquery within the from clause. From this
3073 point on, any joined tables are inaccessible to ->search on the resultset (as if
3074 it were simply where-filtered without joins). For example:
3076 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3078 # 'x' now pollutes the query namespace
3080 # So the following works as expected
3081 my $ok_rs = $rs->search({'x.other' => 1});
3083 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3084 # def) we look for one row with contradictory terms and join in another table
3085 # (aliased 'x_2') which we never use
3086 my $broken_rs = $rs->search({'x.name' => 'def'});
3088 my $rs2 = $rs->as_subselect_rs;
3090 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3091 my $not_joined_rs = $rs2->search({'x.other' => 1});
3093 # works as expected: finds a 'table' row related to two x rows (abc and def)
3094 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3096 Another example of when one might use this would be to select a subset of
3097 columns in a group by clause:
3099 my $rs = $schema->resultset('Bar')->search(undef, {
3100 group_by => [qw{ id foo_id baz_id }],
3101 })->as_subselect_rs->search(undef, {
3102 columns => [qw{ id foo_id }]
3105 In the above example normally columns would have to be equal to the group by,
3106 but because we isolated the group by into a subselect the above works.
3110 sub as_subselect_rs {
3113 my $attrs = $self->_resolved_attrs;
3115 my $fresh_rs = (ref $self)->new (
3116 $self->result_source
3119 # these pieces will be locked in the subquery
3120 delete $fresh_rs->{cond};
3121 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3123 return $fresh_rs->search( {}, {
3125 $attrs->{alias} => $self->as_query,
3126 -alias => $attrs->{alias},
3127 -rsrc => $self->result_source,
3129 alias => $attrs->{alias},
3133 # This code is called by search_related, and makes sure there
3134 # is clear separation between the joins before, during, and
3135 # after the relationship. This information is needed later
3136 # in order to properly resolve prefetch aliases (any alias
3137 # with a relation_chain_depth less than the depth of the
3138 # current prefetch is not considered)
3140 # The increments happen twice per join. An even number means a
3141 # relationship specified via a search_related, whereas an odd
3142 # number indicates a join/prefetch added via attributes
3144 # Also this code will wrap the current resultset (the one we
3145 # chain to) in a subselect IFF it contains limiting attributes
3146 sub _chain_relationship {
3147 my ($self, $rel) = @_;
3148 my $source = $self->result_source;
3149 my $attrs = { %{$self->{attrs}||{}} };
3151 # we need to take the prefetch the attrs into account before we
3152 # ->_resolve_join as otherwise they get lost - captainL
3153 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3155 delete @{$attrs}{qw/join prefetch collapse group_by distinct select as columns +select +as +columns/};
3157 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3160 my @force_subq_attrs = qw/offset rows group_by having/;
3163 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3165 $self->_has_resolved_attr (@force_subq_attrs)
3167 # Nuke the prefetch (if any) before the new $rs attrs
3168 # are resolved (prefetch is useless - we are wrapping
3169 # a subquery anyway).
3170 my $rs_copy = $self->search;
3171 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3172 $rs_copy->{attrs}{join},
3173 delete $rs_copy->{attrs}{prefetch},
3178 -alias => $attrs->{alias},
3179 $attrs->{alias} => $rs_copy->as_query,
3181 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3182 $seen->{-relation_chain_depth} = 0;
3184 elsif ($attrs->{from}) { #shallow copy suffices
3185 $from = [ @{$attrs->{from}} ];
3190 -alias => $attrs->{alias},
3191 $attrs->{alias} => $source->from,
3195 my $jpath = ($seen->{-relation_chain_depth})
3196 ? $from->[-1][0]{-join_path}
3199 my @requested_joins = $source->_resolve_join(
3206 push @$from, @requested_joins;
3208 $seen->{-relation_chain_depth}++;
3210 # if $self already had a join/prefetch specified on it, the requested
3211 # $rel might very well be already included. What we do in this case
3212 # is effectively a no-op (except that we bump up the chain_depth on
3213 # the join in question so we could tell it *is* the search_related)
3216 # we consider the last one thus reverse
3217 for my $j (reverse @requested_joins) {
3218 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3219 if ($rel eq $last_j) {
3220 $j->[0]{-relation_chain_depth}++;
3226 unless ($already_joined) {
3227 push @$from, $source->_resolve_join(
3235 $seen->{-relation_chain_depth}++;
3237 return {%$attrs, from => $from, seen_join => $seen};
3240 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
3241 sub _resolved_attrs_copy {
3243 return { %{$self->_resolved_attrs (@_)} };
3246 sub _resolved_attrs {
3248 return $self->{_attrs} if $self->{_attrs};
3250 my $attrs = { %{ $self->{attrs} || {} } };
3251 my $source = $self->result_source;
3252 my $alias = $attrs->{alias};
3254 # default selection list
3255 $attrs->{columns} = [ $source->columns ]
3256 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3258 # merge selectors together
3259 for (qw/columns select as/) {
3260 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3261 if $attrs->{$_} or $attrs->{"+$_"};
3264 # disassemble columns
3266 if (my $cols = delete $attrs->{columns}) {
3267 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3268 if (ref $c eq 'HASH') {
3269 for my $as (keys %$c) {
3270 push @sel, $c->{$as};
3281 # when trying to weed off duplicates later do not go past this point -
3282 # everything added from here on is unbalanced "anyone's guess" stuff
3283 my $dedup_stop_idx = $#as;
3285 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3287 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3288 if $attrs->{select};
3290 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3291 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3293 # disqualify all $alias.col as-bits (inflate-map mandated)
3294 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3296 # de-duplicate the result (remove *identical* select/as pairs)
3297 # and also die on duplicate {as} pointing to different {select}s
3298 # not using a c-style for as the condition is prone to shrinkage
3301 while ($i <= $dedup_stop_idx) {
3302 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3307 elsif ($seen->{$as[$i]}++) {
3308 $self->throw_exception(
3309 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3317 $attrs->{select} = \@sel;
3318 $attrs->{as} = \@as;
3320 $attrs->{from} ||= [{
3322 -alias => $self->{attrs}{alias},
3323 $self->{attrs}{alias} => $source->from,
3326 if ( $attrs->{join} || $attrs->{prefetch} ) {
3328 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3329 if ref $attrs->{from} ne 'ARRAY';
3331 my $join = (delete $attrs->{join}) || {};
3333 if ( defined $attrs->{prefetch} ) {
3334 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3337 $attrs->{from} = # have to copy here to avoid corrupting the original
3339 @{ $attrs->{from} },
3340 $source->_resolve_join(
3343 { %{ $attrs->{seen_join} || {} } },
3344 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3345 ? $attrs->{from}[-1][0]{-join_path}
3352 if ( defined $attrs->{order_by} ) {
3353 $attrs->{order_by} = (
3354 ref( $attrs->{order_by} ) eq 'ARRAY'
3355 ? [ @{ $attrs->{order_by} } ]
3356 : [ $attrs->{order_by} || () ]
3360 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3361 $attrs->{group_by} = [ $attrs->{group_by} ];
3364 # generate the distinct induced group_by early, as prefetch will be carried via a
3365 # subquery (since a group_by is present)
3366 if (delete $attrs->{distinct}) {
3367 if ($attrs->{group_by}) {
3368 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3371 # distinct affects only the main selection part, not what prefetch may
3373 $attrs->{group_by} = $source->storage->_group_over_selection (
3381 # generate selections based on the prefetch helper
3383 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3384 if defined $attrs->{prefetch};
3388 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3389 if $attrs->{_dark_selector};
3391 $attrs->{collapse} = 1;
3393 # this is a separate structure (we don't look in {from} directly)
3394 # as the resolver needs to shift things off the lists to work
3395 # properly (identical-prefetches on different branches)
3397 if (ref $attrs->{from} eq 'ARRAY') {
3399 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3401 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3402 next unless $j->[0]{-alias};
3403 next unless $j->[0]{-join_path};
3404 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3406 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3409 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3410 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3414 my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map );
3416 # we need to somehow mark which columns came from prefetch
3418 my $sel_end = $#{$attrs->{select}};
3419 $attrs->{_prefetch_selector_range} = [ $sel_end + 1, $sel_end + @prefetch ];
3422 push @{ $attrs->{select} }, (map { $_->[0] } @prefetch);
3423 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
3426 # run through the resulting joinstructure (starting from our current slot)
3427 # and unset collapse if proven unnesessary
3428 if ($attrs->{collapse} && ref $attrs->{from} eq 'ARRAY') {
3430 if (@{$attrs->{from}} > 1) {
3432 # find where our table-spec starts and consider only things after us
3433 my @fromlist = @{$attrs->{from}};
3435 my $t = shift @fromlist;
3436 $t = $t->[0] if ref $t eq 'ARRAY'; #me vs join from-spec mismatch
3437 last if ($t->{-alias} && $t->{-alias} eq $alias);
3441 $attrs->{collapse} = ! $_->[0]{-is_single}
3446 # no joins - no collapse
3447 $attrs->{collapse} = 0;
3451 $attrs->{_single_object_inflation} = ! List::Util::first { $_ =~ /\./ } @{$attrs->{as}};
3453 # if both page and offset are specified, produce a combined offset
3454 # even though it doesn't make much sense, this is what pre 081xx has
3456 if (my $page = delete $attrs->{page}) {
3458 ($attrs->{rows} * ($page - 1))
3460 ($attrs->{offset} || 0)
3464 return $self->{_attrs} = $attrs;
3468 my ($self, $attr) = @_;
3470 if (ref $attr eq 'HASH') {
3471 return $self->_rollout_hash($attr);
3472 } elsif (ref $attr eq 'ARRAY') {
3473 return $self->_rollout_array($attr);
3479 sub _rollout_array {
3480 my ($self, $attr) = @_;
3483 foreach my $element (@{$attr}) {
3484 if (ref $element eq 'HASH') {
3485 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3486 } elsif (ref $element eq 'ARRAY') {
3487 # XXX - should probably recurse here
3488 push( @rolled_array, @{$self->_rollout_array($element)} );
3490 push( @rolled_array, $element );
3493 return \@rolled_array;
3497 my ($self, $attr) = @_;
3500 foreach my $key (keys %{$attr}) {
3501 push( @rolled_array, { $key => $attr->{$key} } );
3503 return \@rolled_array;
3506 sub _calculate_score {
3507 my ($self, $a, $b) = @_;
3509 if (defined $a xor defined $b) {
3512 elsif (not defined $a) {
3516 if (ref $b eq 'HASH') {
3517 my ($b_key) = keys %{$b};
3518 if (ref $a eq 'HASH') {
3519 my ($a_key) = keys %{$a};
3520 if ($a_key eq $b_key) {
3521 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3526 return ($a eq $b_key) ? 1 : 0;
3529 if (ref $a eq 'HASH') {
3530 my ($a_key) = keys %{$a};
3531 return ($b eq $a_key) ? 1 : 0;
3533 return ($b eq $a) ? 1 : 0;
3538 sub _merge_joinpref_attr {
3539 my ($self, $orig, $import) = @_;
3541 return $import unless defined($orig);
3542 return $orig unless defined($import);
3544 $orig = $self->_rollout_attr($orig);
3545 $import = $self->_rollout_attr($import);
3548 foreach my $import_element ( @{$import} ) {
3549 # find best candidate from $orig to merge $b_element into
3550 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3551 foreach my $orig_element ( @{$orig} ) {
3552 my $score = $self->_calculate_score( $orig_element, $import_element );
3553 if ($score > $best_candidate->{score}) {
3554 $best_candidate->{position} = $position;
3555 $best_candidate->{score} = $score;
3559 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3560 $import_key = '' if not defined $import_key;
3562 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3563 push( @{$orig}, $import_element );
3565 my $orig_best = $orig->[$best_candidate->{position}];
3566 # merge orig_best and b_element together and replace original with merged
3567 if (ref $orig_best ne 'HASH') {
3568 $orig->[$best_candidate->{position}] = $import_element;
3569 } elsif (ref $import_element eq 'HASH') {
3570 my ($key) = keys %{$orig_best};
3571 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3574 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3585 require Hash::Merge;
3586 my $hm = Hash::Merge->new;
3588 $hm->specify_behavior({
3591 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3593 if ($defl xor $defr) {
3594 return [ $defl ? $_[0] : $_[1] ];
3599 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3603 return [$_[0], $_[1]];
3607 return $_[1] if !defined $_[0];
3608 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3609 return [$_[0], @{$_[1]}]
3612 return [] if !defined $_[0] and !keys %{$_[1]};
3613 return [ $_[1] ] if !defined $_[0];
3614 return [ $_[0] ] if !keys %{$_[1]};
3615 return [$_[0], $_[1]]
3620 return $_[0] if !defined $_[1];
3621 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3622 return [@{$_[0]}, $_[1]]
3625 my @ret = @{$_[0]} or return $_[1];
3626 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3627 my %idx = map { $_ => 1 } @ret;
3628 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3632 return [ $_[1] ] if ! @{$_[0]};
3633 return $_[0] if !keys %{$_[1]};
3634 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3635 return [ @{$_[0]}, $_[1] ];
3640 return [] if !keys %{$_[0]} and !defined $_[1];
3641 return [ $_[0] ] if !defined $_[1];
3642 return [ $_[1] ] if !keys %{$_[0]};
3643 return [$_[0], $_[1]]
3646 return [] if !keys %{$_[0]} and !@{$_[1]};
3647 return [ $_[0] ] if !@{$_[1]};
3648 return $_[1] if !keys %{$_[0]};
3649 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3650 return [ $_[0], @{$_[1]} ];
3653 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3654 return [ $_[0] ] if !keys %{$_[1]};
3655 return [ $_[1] ] if !keys %{$_[0]};
3656 return [ $_[0] ] if $_[0] eq $_[1];
3657 return [ $_[0], $_[1] ];
3660 } => 'DBIC_RS_ATTR_MERGER');
3664 return $hm->merge ($_[1], $_[2]);
3668 sub STORABLE_freeze {
3669 my ($self, $cloning) = @_;
3670 my $to_serialize = { %$self };
3672 # A cursor in progress can't be serialized (and would make little sense anyway)
3673 delete $to_serialize->{cursor};
3675 # nor is it sensical to store a not-yet-fired-count pager
3676 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3677 delete $to_serialize->{pager};
3680 Storable::nfreeze($to_serialize);
3683 # need this hook for symmetry
3685 my ($self, $cloning, $serialized) = @_;
3687 %$self = %{ Storable::thaw($serialized) };
3693 =head2 throw_exception
3695 See L<DBIx::Class::Schema/throw_exception> for details.
3699 sub throw_exception {
3702 if (ref $self and my $rsrc = $self->result_source) {
3703 $rsrc->throw_exception(@_)
3706 DBIx::Class::Exception->throw(@_);
3710 # XXX: FIXME: Attributes docs need clearing up
3714 Attributes are used to refine a ResultSet in various ways when
3715 searching for data. They can be passed to any method which takes an
3716 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3719 These are in no particular order:
3725 =item Value: ( $order_by | \@order_by | \%order_by )
3729 Which column(s) to order the results by.
3731 [The full list of suitable values is documented in
3732 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3735 If a single column name, or an arrayref of names is supplied, the
3736 argument is passed through directly to SQL. The hashref syntax allows
3737 for connection-agnostic specification of ordering direction:
3739 For descending order:
3741 order_by => { -desc => [qw/col1 col2 col3/] }
3743 For explicit ascending order:
3745 order_by => { -asc => 'col' }
3747 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3748 supported, although you are strongly encouraged to use the hashref
3749 syntax as outlined above.
3755 =item Value: \@columns
3759 Shortcut to request a particular set of columns to be retrieved. Each
3760 column spec may be a string (a table column name), or a hash (in which
3761 case the key is the C<as> value, and the value is used as the C<select>
3762 expression). Adds C<me.> onto the start of any column without a C<.> in
3763 it and sets C<select> from that, then auto-populates C<as> from
3764 C<select> as normal. (You may also use the C<cols> attribute, as in
3765 earlier versions of DBIC.)
3767 Essentially C<columns> does the same as L</select> and L</as>.
3769 columns => [ 'foo', { bar => 'baz' } ]
3773 select => [qw/foo baz/],
3780 =item Value: \@columns
3784 Indicates additional columns to be selected from storage. Works the same
3785 as L</columns> but adds columns to the selection. (You may also use the
3786 C<include_columns> attribute, as in earlier versions of DBIC). For
3789 $schema->resultset('CD')->search(undef, {
3790 '+columns' => ['artist.name'],
3794 would return all CDs and include a 'name' column to the information
3795 passed to object inflation. Note that the 'artist' is the name of the
3796 column (or relationship) accessor, and 'name' is the name of the column
3797 accessor in the related table.
3799 B<NOTE:> You need to explicitly quote '+columns' when defining the attribute.
3800 Not doing so causes Perl to incorrectly interpret +columns as a bareword with a
3801 unary plus operator before it.
3803 =head2 include_columns
3807 =item Value: \@columns
3811 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3817 =item Value: \@select_columns
3821 Indicates which columns should be selected from the storage. You can use
3822 column names, or in the case of RDBMS back ends, function or stored procedure
3825 $rs = $schema->resultset('Employee')->search(undef, {
3828 { count => 'employeeid' },
3829 { max => { length => 'name' }, -as => 'longest_name' }
3834 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
3836 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
3837 use L</select>, to instruct DBIx::Class how to store the result of the column.
3838 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
3839 identifier aliasing. You can however alias a function, so you can use it in
3840 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
3841 attribute> supplied as shown in the example above.
3843 B<NOTE:> You need to explicitly quote '+select'/'+as' when defining the attributes.
3844 Not doing so causes Perl to incorrectly interpret them as a bareword with a
3845 unary plus operator before it.
3851 Indicates additional columns to be selected from storage. Works the same as
3852 L</select> but adds columns to the default selection, instead of specifying
3861 Indicates additional column names for those added via L</+select>. See L</as>.
3869 =item Value: \@inflation_names
3873 Indicates column names for object inflation. That is L</as> indicates the
3874 slot name in which the column value will be stored within the
3875 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
3876 identifier by the C<get_column> method (or via the object accessor B<if one
3877 with the same name already exists>) as shown below. The L</as> attribute has
3878 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
3880 $rs = $schema->resultset('Employee')->search(undef, {
3883 { count => 'employeeid' },
3884 { max => { length => 'name' }, -as => 'longest_name' }
3893 If the object against which the search is performed already has an accessor
3894 matching a column name specified in C<as>, the value can be retrieved using
3895 the accessor as normal:
3897 my $name = $employee->name();
3899 If on the other hand an accessor does not exist in the object, you need to
3900 use C<get_column> instead:
3902 my $employee_count = $employee->get_column('employee_count');
3904 You can create your own accessors if required - see
3905 L<DBIx::Class::Manual::Cookbook> for details.
3911 =item Value: ($rel_name | \@rel_names | \%rel_names)
3915 Contains a list of relationships that should be joined for this query. For
3918 # Get CDs by Nine Inch Nails
3919 my $rs = $schema->resultset('CD')->search(
3920 { 'artist.name' => 'Nine Inch Nails' },
3921 { join => 'artist' }
3924 Can also contain a hash reference to refer to the other relation's relations.
3927 package MyApp::Schema::Track;
3928 use base qw/DBIx::Class/;
3929 __PACKAGE__->table('track');
3930 __PACKAGE__->add_columns(qw/trackid cd position title/);
3931 __PACKAGE__->set_primary_key('trackid');
3932 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3935 # In your application
3936 my $rs = $schema->resultset('Artist')->search(
3937 { 'track.title' => 'Teardrop' },
3939 join => { cd => 'track' },
3940 order_by => 'artist.name',
3944 You need to use the relationship (not the table) name in conditions,
3945 because they are aliased as such. The current table is aliased as "me", so
3946 you need to use me.column_name in order to avoid ambiguity. For example:
3948 # Get CDs from 1984 with a 'Foo' track
3949 my $rs = $schema->resultset('CD')->search(
3952 'tracks.name' => 'Foo'
3954 { join => 'tracks' }
3957 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3958 similarly for a third time). For e.g.
3960 my $rs = $schema->resultset('Artist')->search({
3961 'cds.title' => 'Down to Earth',
3962 'cds_2.title' => 'Popular',
3964 join => [ qw/cds cds/ ],
3967 will return a set of all artists that have both a cd with title 'Down
3968 to Earth' and a cd with title 'Popular'.
3970 If you want to fetch related objects from other tables as well, see C<prefetch>
3973 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3979 =item Value: ($rel_name | \@rel_names | \%rel_names)
3983 Contains one or more relationships that should be fetched along with
3984 the main query (when they are accessed afterwards the data will
3985 already be available, without extra queries to the database). This is
3986 useful for when you know you will need the related objects, because it
3987 saves at least one query:
3989 my $rs = $schema->resultset('Tag')->search(
3998 The initial search results in SQL like the following:
4000 SELECT tag.*, cd.*, artist.* FROM tag
4001 JOIN cd ON tag.cd = cd.cdid
4002 JOIN artist ON cd.artist = artist.artistid
4004 L<DBIx::Class> has no need to go back to the database when we access the
4005 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4008 Simple prefetches will be joined automatically, so there is no need
4009 for a C<join> attribute in the above search.
4011 L</prefetch> can be used with the any of the relationship types and
4012 multiple prefetches can be specified together. Below is a more complex
4013 example that prefetches a CD's artist, its liner notes (if present),
4014 the cover image, the tracks on that cd, and the guests on those
4018 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4019 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4020 My::Schema::CD->has_one( cover_image => 'My::Schema::Artwork' );
4021 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4023 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4025 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4028 my $rs = $schema->resultset('CD')->search(
4032 { artist => 'record_label'}, # belongs_to => belongs_to
4033 'liner_note', # might_have
4034 'cover_image', # has_one
4035 { tracks => 'guests' }, # has_many => has_many
4040 This will produce SQL like the following:
4042 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4046 ON artist.artistid = me.artistid
4047 JOIN record_label record_label
4048 ON record_label.labelid = artist.labelid
4049 LEFT JOIN track tracks
4050 ON tracks.cdid = me.cdid
4051 LEFT JOIN guest guests
4052 ON guests.trackid = track.trackid
4053 LEFT JOIN liner_notes liner_note
4054 ON liner_note.cdid = me.cdid
4055 JOIN cd_artwork cover_image
4056 ON cover_image.cdid = me.cdid
4059 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4060 C<tracks>, and C<guests> of the CD will all be available through the
4061 relationship accessors without the need for additional queries to the
4064 However, there is one caveat to be observed: it can be dangerous to
4065 prefetch more than one L<has_many|DBIx::Class::Relationship/has_many>
4066 relationship on a given level. e.g.:
4068 my $rs = $schema->resultset('CD')->search(
4072 'tracks', # has_many
4073 { cd_to_producer => 'producer' }, # has_many => belongs_to (i.e. m2m)
4078 In fact, C<DBIx::Class> will emit the following warning:
4080 Prefetching multiple has_many rels tracks and cd_to_producer at top
4081 level will explode the number of row objects retrievable via ->next
4082 or ->all. Use at your own risk.
4084 The collapser currently can't identify duplicate tuples for multiple
4085 L<has_many|DBIx::Class::Relationship/has_many> relationships and as a
4086 result the second L<has_many|DBIx::Class::Relationship/has_many>
4087 relation could contain redundant objects.
4089 =head3 Using L</prefetch> with L</join>
4091 L</prefetch> implies a L</join> with the equivalent argument, and is
4092 properly merged with any existing L</join> specification. So the
4095 my $rs = $schema->resultset('CD')->search(
4096 {'record_label.name' => 'Music Product Ltd.'},
4098 join => {artist => 'record_label'},
4099 prefetch => 'artist',
4103 ... will work, searching on the record label's name, but only
4104 prefetching the C<artist>.
4106 =head3 Using L</prefetch> with L</select> / L</+select> / L</as> / L</+as>
4108 L</prefetch> implies a L</+select>/L</+as> with the fields of the
4109 prefetched relations. So given:
4111 my $rs = $schema->resultset('CD')->search(
4114 select => ['cd.title'],
4116 prefetch => 'artist',
4120 The L</select> becomes: C<'cd.title', 'artist.*'> and the L</as>
4121 becomes: C<'cd_title', 'artist.*'>.
4125 Prefetch does a lot of deep magic. As such, it may not behave exactly
4126 as you might expect.
4132 Prefetch uses the L</cache> to populate the prefetched relationships. This
4133 may or may not be what you want.
4137 If you specify a condition on a prefetched relationship, ONLY those
4138 rows that match the prefetched condition will be fetched into that relationship.
4139 This means that adding prefetch to a search() B<may alter> what is returned by
4140 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4142 my $artist_rs = $schema->resultset('Artist')->search({
4148 my $count = $artist_rs->first->cds->count;
4150 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4152 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4154 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4156 that cmp_ok() may or may not pass depending on the datasets involved. This
4157 behavior may or may not survive the 0.09 transition.
4169 Makes the resultset paged and specifies the page to retrieve. Effectively
4170 identical to creating a non-pages resultset and then calling ->page($page)
4173 If L</rows> attribute is not specified it defaults to 10 rows per page.
4175 When you have a paged resultset, L</count> will only return the number
4176 of rows in the page. To get the total, use the L</pager> and call
4177 C<total_entries> on it.
4187 Specifies the maximum number of rows for direct retrieval or the number of
4188 rows per page if the page attribute or method is used.
4194 =item Value: $offset
4198 Specifies the (zero-based) row number for the first row to be returned, or the
4199 of the first row of the first page if paging is used.
4201 =head2 software_limit
4205 =item Value: (0 | 1)
4209 When combined with L</rows> and/or L</offset> the generated SQL will not
4210 include any limit dialect stanzas. Instead the entire result will be selected
4211 as if no limits were specified, and DBIC will perform the limit locally, by
4212 artificially advancing and finishing the resulting L</cursor>.
4214 This is the recommended way of performing resultset limiting when no sane RDBMS
4215 implementation is available (e.g.
4216 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4217 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4223 =item Value: \@columns
4227 A arrayref of columns to group by. Can include columns of joined tables.
4229 group_by => [qw/ column1 column2 ... /]
4235 =item Value: $condition
4239 HAVING is a select statement attribute that is applied between GROUP BY and
4240 ORDER BY. It is applied to the after the grouping calculations have been
4243 having => { 'count_employee' => { '>=', 100 } }
4245 or with an in-place function in which case literal SQL is required:
4247 having => \[ 'count(employee) >= ?', [ count => 100 ] ]
4253 =item Value: (0 | 1)
4257 Set to 1 to group by all columns. If the resultset already has a group_by
4258 attribute, this setting is ignored and an appropriate warning is issued.
4264 Adds to the WHERE clause.
4266 # only return rows WHERE deleted IS NULL for all searches
4267 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
4269 Can be overridden by passing C<< { where => undef } >> as an attribute
4272 For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
4278 Set to 1 to cache search results. This prevents extra SQL queries if you
4279 revisit rows in your ResultSet:
4281 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4283 while( my $artist = $resultset->next ) {
4287 $rs->first; # without cache, this would issue a query
4289 By default, searches are not cached.
4291 For more examples of using these attributes, see
4292 L<DBIx::Class::Manual::Cookbook>.
4298 =item Value: ( 'update' | 'shared' )
4302 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT