1 package DBIx::Class::ResultSet;
5 use base qw/DBIx::Class/;
7 use DBIx::Class::ResultSetColumn;
8 use Scalar::Util qw/blessed weaken/;
10 use Data::Compare (); # no imports!!! guard against insane architecture
12 # not importing first() as it will clash with our own method
16 # De-duplication in _merge_attr() is disabled, but left in for reference
17 # (the merger is used for other things that ought not to be de-duped)
18 *__HM_DEDUP = sub () { 0 };
28 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class result_source/);
32 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
36 my $users_rs = $schema->resultset('User');
37 while( $user = $users_rs->next) {
38 print $user->username;
41 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
42 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
46 A ResultSet is an object which stores a set of conditions representing
47 a query. It is the backbone of DBIx::Class (i.e. the really
48 important/useful bit).
50 No SQL is executed on the database when a ResultSet is created, it
51 just stores all the conditions needed to create the query.
53 A basic ResultSet representing the data of an entire table is returned
54 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
55 L<Source|DBIx::Class::Manual::Glossary/Source> name.
57 my $users_rs = $schema->resultset('User');
59 A new ResultSet is returned from calling L</search> on an existing
60 ResultSet. The new one will contain all the conditions of the
61 original, plus any new conditions added in the C<search> call.
63 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
64 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
67 The query that the ResultSet represents is B<only> executed against
68 the database when these methods are called:
69 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
71 If a resultset is used in a numeric context it returns the L</count>.
72 However, if it is used in a boolean context it is B<always> true. So if
73 you want to check if a resultset has any results, you must use C<if $rs
76 =head1 CUSTOM ResultSet CLASSES THAT USE Moose
78 If you want to make your custom ResultSet classes with L<Moose>, use a template
81 package MyApp::Schema::ResultSet::User;
84 use namespace::autoclean;
86 extends 'DBIx::Class::ResultSet';
88 sub BUILDARGS { $_[2] }
92 __PACKAGE__->meta->make_immutable;
96 The L<MooseX::NonMoose> is necessary so that the L<Moose> constructor does not
97 clash with the regular ResultSet constructor. Alternatively, you can use:
99 __PACKAGE__->meta->make_immutable(inline_constructor => 0);
101 The L<BUILDARGS|Moose::Manual::Construction/BUILDARGS> is necessary because the
102 signature of the ResultSet C<new> is C<< ->new($source, \%args) >>.
106 =head2 Chaining resultsets
108 Let's say you've got a query that needs to be run to return some data
109 to the user. But, you have an authorization system in place that
110 prevents certain users from seeing certain information. So, you want
111 to construct the basic query in one method, but add constraints to it in
116 my $request = $self->get_request; # Get a request object somehow.
117 my $schema = $self->result_source->schema;
119 my $cd_rs = $schema->resultset('CD')->search({
120 title => $request->param('title'),
121 year => $request->param('year'),
124 $cd_rs = $self->apply_security_policy( $cd_rs );
126 return $cd_rs->all();
129 sub apply_security_policy {
138 =head3 Resolving conditions and attributes
140 When a resultset is chained from another resultset, conditions and
141 attributes with the same keys need resolving.
143 L</join>, L</prefetch>, L</+select>, L</+as> attributes are merged
144 into the existing ones from the original resultset.
146 The L</where> and L</having> attributes, and any search conditions, are
147 merged with an SQL C<AND> to the existing condition from the original
150 All other attributes are overridden by any new ones supplied in the
153 =head2 Multiple queries
155 Since a resultset just defines a query, you can do all sorts of
156 things with it with the same object.
158 # Don't hit the DB yet.
159 my $cd_rs = $schema->resultset('CD')->search({
160 title => 'something',
164 # Each of these hits the DB individually.
165 my $count = $cd_rs->count;
166 my $most_recent = $cd_rs->get_column('date_released')->max();
167 my @records = $cd_rs->all;
169 And it's not just limited to SELECT statements.
175 $cd_rs->create({ artist => 'Fred' });
177 Which is the same as:
179 $schema->resultset('CD')->create({
180 title => 'something',
185 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
193 =item Arguments: L<$source|DBIx::Class::ResultSource>, L<\%attrs?|/ATTRIBUTES>
195 =item Return Value: L<$resultset|/search>
199 The resultset constructor. Takes a source object (usually a
200 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
201 L</ATTRIBUTES> below). Does not perform any queries -- these are
202 executed as needed by the other methods.
204 Generally you never construct a resultset manually. Instead you get one
206 C<< $schema->L<resultset|DBIx::Class::Schema/resultset>('$source_name') >>
207 or C<< $another_resultset->L<search|/search>(...) >> (the later called in
210 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
216 If called on an object, proxies to L</new_result> instead, so
218 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
220 will return a CD object, not a ResultSet, and is equivalent to:
222 my $cd = $schema->resultset('CD')->new_result({ title => 'Spoon' });
224 Please also keep in mind that many internals call L</new_result> directly,
225 so overloading this method with the idea of intercepting new result object
226 creation B<will not work>. See also warning pertaining to L</create>.
234 return $class->new_result(@_) if ref $class;
236 my ($source, $attrs) = @_;
237 $source = $source->resolve
238 if $source->isa('DBIx::Class::ResultSourceHandle');
239 $attrs = { %{$attrs||{}} };
241 if ($attrs->{page}) {
242 $attrs->{rows} ||= 10;
245 $attrs->{alias} ||= 'me';
248 result_source => $source,
249 cond => $attrs->{where},
254 # if there is a dark selector, this means we are already in a
255 # chain and the cleanup/sanification was taken care of by
257 $self->_normalize_selection($attrs)
258 unless $attrs->{_dark_selector};
261 $attrs->{result_class} || $source->result_class
271 =item Arguments: L<$cond|DBIx::Class::SQLMaker> | undef, L<\%attrs?|/ATTRIBUTES>
273 =item Return Value: $resultset (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
277 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
278 my $new_rs = $cd_rs->search({ year => 2005 });
280 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
281 # year = 2005 OR year = 2004
283 In list context, C<< ->all() >> is called implicitly on the resultset, thus
284 returning a list of L<result|DBIx::Class::Manual::ResultClass> objects instead.
285 To avoid that, use L</search_rs>.
287 If you need to pass in additional attributes but no additional condition,
288 call it as C<search(undef, \%attrs)>.
290 # "SELECT name, artistid FROM $artist_table"
291 my @all_artists = $schema->resultset('Artist')->search(undef, {
292 columns => [qw/name artistid/],
295 For a list of attributes that can be passed to C<search>, see
296 L</ATTRIBUTES>. For more examples of using this function, see
297 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
298 documentation for the first argument, see L<SQL::Abstract>
299 and its extension L<DBIx::Class::SQLMaker>.
301 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
305 Note that L</search> does not process/deflate any of the values passed in the
306 L<SQL::Abstract>-compatible search condition structure. This is unlike other
307 condition-bound methods L</new_result>, L</create> and L</find>. The user must ensure
308 manually that any value passed to this method will stringify to something the
309 RDBMS knows how to deal with. A notable example is the handling of L<DateTime>
310 objects, for more info see:
311 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
317 my $rs = $self->search_rs( @_ );
322 elsif (defined wantarray) {
326 # we can be called by a relationship helper, which in
327 # turn may be called in void context due to some braindead
328 # overload or whatever else the user decided to be clever
329 # at this particular day. Thus limit the exception to
330 # external code calls only
331 $self->throw_exception ('->search is *not* a mutator, calling it in void context makes no sense')
332 if (caller)[0] !~ /^\QDBIx::Class::/;
342 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
344 =item Return Value: L<$resultset|/search>
348 This method does the same exact thing as search() except it will
349 always return a resultset, even in list context.
356 my $rsrc = $self->result_source;
357 my ($call_cond, $call_attrs);
359 # Special-case handling for (undef, undef) or (undef)
360 # Note that (foo => undef) is valid deprecated syntax
361 @_ = () if not scalar grep { defined $_ } @_;
367 # fish out attrs in the ($condref, $attr) case
368 elsif (@_ == 2 and ( ! defined $_[0] or (ref $_[0]) ne '') ) {
369 ($call_cond, $call_attrs) = @_;
372 $self->throw_exception('Odd number of arguments to search')
376 carp_unique 'search( %condition ) is deprecated, use search( \%condition ) instead'
377 unless $rsrc->result_class->isa('DBIx::Class::CDBICompat');
379 for my $i (0 .. $#_) {
381 $self->throw_exception ('All keys in condition key/value pairs must be plain scalars')
382 if (! defined $_[$i] or ref $_[$i] ne '');
388 # see if we can keep the cache (no $rs changes)
390 my %safe = (alias => 1, cache => 1);
391 if ( ! List::Util::first { !$safe{$_} } keys %$call_attrs and (
394 ref $_[0] eq 'HASH' && ! keys %{$_[0]}
396 ref $_[0] eq 'ARRAY' && ! @{$_[0]}
398 $cache = $self->get_cache;
401 my $old_attrs = { %{$self->{attrs}} };
402 my $old_having = delete $old_attrs->{having};
403 my $old_where = delete $old_attrs->{where};
405 my $new_attrs = { %$old_attrs };
407 # take care of call attrs (only if anything is changing)
408 if ($call_attrs and keys %$call_attrs) {
410 # copy for _normalize_selection
411 $call_attrs = { %$call_attrs };
413 my @selector_attrs = qw/select as columns cols +select +as +columns include_columns/;
415 # reset the current selector list if new selectors are supplied
416 if (List::Util::first { exists $call_attrs->{$_} } qw/columns cols select as/) {
417 delete @{$old_attrs}{(@selector_attrs, '_dark_selector')};
420 # Normalize the new selector list (operates on the passed-in attr structure)
421 # Need to do it on every chain instead of only once on _resolved_attrs, in
422 # order to allow detection of empty vs partial 'as'
423 $call_attrs->{_dark_selector} = $old_attrs->{_dark_selector}
424 if $old_attrs->{_dark_selector};
425 $self->_normalize_selection ($call_attrs);
427 # start with blind overwriting merge, exclude selector attrs
428 $new_attrs = { %{$old_attrs}, %{$call_attrs} };
429 delete @{$new_attrs}{@selector_attrs};
431 for (@selector_attrs) {
432 $new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
433 if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
436 # older deprecated name, use only if {columns} is not there
437 if (my $c = delete $new_attrs->{cols}) {
438 if ($new_attrs->{columns}) {
439 carp "Resultset specifies both the 'columns' and the legacy 'cols' attributes - ignoring 'cols'";
442 $new_attrs->{columns} = $c;
447 # join/prefetch use their own crazy merging heuristics
448 foreach my $key (qw/join prefetch/) {
449 $new_attrs->{$key} = $self->_merge_joinpref_attr($old_attrs->{$key}, $call_attrs->{$key})
450 if exists $call_attrs->{$key};
453 # stack binds together
454 $new_attrs->{bind} = [ @{ $old_attrs->{bind} || [] }, @{ $call_attrs->{bind} || [] } ];
458 for ($old_where, $call_cond) {
460 $new_attrs->{where} = $self->_stack_cond (
461 $_, $new_attrs->{where}
466 if (defined $old_having) {
467 $new_attrs->{having} = $self->_stack_cond (
468 $old_having, $new_attrs->{having}
472 my $rs = (ref $self)->new($rsrc, $new_attrs);
474 $rs->set_cache($cache) if ($cache);
480 sub _normalize_selection {
481 my ($self, $attrs) = @_;
484 $attrs->{'+columns'} = $self->_merge_attr($attrs->{'+columns'}, delete $attrs->{include_columns})
485 if exists $attrs->{include_columns};
487 # columns are always placed first, however
489 # Keep the X vs +X separation until _resolved_attrs time - this allows to
490 # delay the decision on whether to use a default select list ($rsrc->columns)
491 # allowing stuff like the remove_columns helper to work
493 # select/as +select/+as pairs need special handling - the amount of select/as
494 # elements in each pair does *not* have to be equal (think multicolumn
495 # selectors like distinct(foo, bar) ). If the selector is bare (no 'as'
496 # supplied at all) - try to infer the alias, either from the -as parameter
497 # of the selector spec, or use the parameter whole if it looks like a column
498 # name (ugly legacy heuristic). If all fails - leave the selector bare (which
499 # is ok as well), but make sure no more additions to the 'as' chain take place
500 for my $pref ('', '+') {
502 my ($sel, $as) = map {
503 my $key = "${pref}${_}";
505 my $val = [ ref $attrs->{$key} eq 'ARRAY'
507 : $attrs->{$key} || ()
509 delete $attrs->{$key};
513 if (! @$as and ! @$sel ) {
516 elsif (@$as and ! @$sel) {
517 $self->throw_exception(
518 "Unable to handle ${pref}as specification (@$as) without a corresponding ${pref}select"
522 # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
523 # if any @$as has been supplied we assume the user knows what (s)he is doing
524 # and blindly keep stacking up pieces
525 unless ($attrs->{_dark_selector}) {
528 if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
529 push @$as, $_->{-as};
531 # assume any plain no-space, no-parenthesis string to be a column spec
532 # FIXME - this is retarded but is necessary to support shit like 'count(foo)'
533 elsif ( ! ref $_ and $_ =~ /^ [^\s\(\)]+ $/x) {
536 # if all else fails - raise a flag that no more aliasing will be allowed
538 $attrs->{_dark_selector} = {
540 string => ($dark_sel_dumper ||= do {
541 require Data::Dumper::Concise;
542 Data::Dumper::Concise::DumperObject()->Indent(0);
543 })->Values([$_])->Dump
551 elsif (@$as < @$sel) {
552 $self->throw_exception(
553 "Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
556 elsif ($pref and $attrs->{_dark_selector}) {
557 $self->throw_exception(
558 "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
564 $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
565 $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
570 my ($self, $left, $right) = @_;
572 # collapse single element top-level conditions
573 # (single pass only, unlikely to need recursion)
574 for ($left, $right) {
575 if (ref $_ eq 'ARRAY') {
583 elsif (ref $_ eq 'HASH') {
584 my ($first, $more) = keys %$_;
587 if (! defined $first) {
591 elsif (! defined $more) {
592 if ($first eq '-and' and ref $_->{'-and'} eq 'HASH') {
595 elsif ($first eq '-or' and ref $_->{'-or'} eq 'ARRAY') {
602 # merge hashes with weeding out of duplicates (simple cases only)
603 if (ref $left eq 'HASH' and ref $right eq 'HASH') {
605 # shallow copy to destroy
606 $right = { %$right };
607 for (grep { exists $right->{$_} } keys %$left) {
608 # the use of eq_deeply here is justified - the rhs of an
609 # expression can contain a lot of twisted weird stuff
610 delete $right->{$_} if Data::Compare::Compare( $left->{$_}, $right->{$_} );
613 $right = undef unless keys %$right;
617 if (defined $left xor defined $right) {
618 return defined $left ? $left : $right;
620 elsif (! defined $left) {
624 return { -and => [ $left, $right ] };
628 =head2 search_literal
630 B<CAVEAT>: C<search_literal> is provided for Class::DBI compatibility and
631 should only be used in that context. C<search_literal> is a convenience
632 method. It is equivalent to calling C<< $schema->search(\[]) >>, but if you
633 want to ensure columns are bound correctly, use L</search>.
635 See L<DBIx::Class::Manual::Cookbook/Searching> and
636 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
637 require C<search_literal>.
641 =item Arguments: $sql_fragment, @standalone_bind_values
643 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
647 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
648 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
650 Pass a literal chunk of SQL to be added to the conditional part of the
653 Example of how to use C<search> instead of C<search_literal>
655 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
656 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
661 my ($self, $sql, @bind) = @_;
663 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
666 return $self->search(\[ $sql, map [ {} => $_ ], @bind ], ($attr || () ));
673 =item Arguments: \%columns_values | @pk_values, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
675 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
679 Finds and returns a single row based on supplied criteria. Takes either a
680 hashref with the same format as L</create> (including inference of foreign
681 keys from related objects), or a list of primary key values in the same
682 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
683 declaration on the L</result_source>.
685 In either case an attempt is made to combine conditions already existing on
686 the resultset with the condition passed to this method.
688 To aid with preparing the correct query for the storage you may supply the
689 C<key> attribute, which is the name of a
690 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
691 unique constraint corresponding to the
692 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
693 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
694 to construct a query that satisfies the named unique constraint fully (
695 non-NULL values for each column member of the constraint) an exception is
698 If no C<key> is specified, the search is carried over all unique constraints
699 which are fully defined by the available condition.
701 If no such constraint is found, C<find> currently defaults to a simple
702 C<< search->(\%column_values) >> which may or may not do what you expect.
703 Note that this fallback behavior may be deprecated in further versions. If
704 you need to search with arbitrary conditions - use L</search>. If the query
705 resulting from this fallback produces more than one row, a warning to the
706 effect is issued, though only the first row is constructed and returned as
709 In addition to C<key>, L</find> recognizes and applies standard
710 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
712 Note that if you have extra concerns about the correctness of the resulting
713 query you need to specify the C<key> attribute and supply the entire condition
714 as an argument to find (since it is not always possible to perform the
715 combination of the resultset condition with the supplied one, especially if
716 the resultset condition contains literal sql).
718 For example, to find a row by its primary key:
720 my $cd = $schema->resultset('CD')->find(5);
722 You can also find a row by a specific unique constraint:
724 my $cd = $schema->resultset('CD')->find(
726 artist => 'Massive Attack',
727 title => 'Mezzanine',
729 { key => 'cd_artist_title' }
732 See also L</find_or_create> and L</update_or_create>.
738 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
740 my $rsrc = $self->result_source;
743 if (exists $attrs->{key}) {
744 $constraint_name = defined $attrs->{key}
746 : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
750 # Parse out the condition from input
753 if (ref $_[0] eq 'HASH') {
754 $call_cond = { %{$_[0]} };
757 # if only values are supplied we need to default to 'primary'
758 $constraint_name = 'primary' unless defined $constraint_name;
760 my @c_cols = $rsrc->unique_constraint_columns($constraint_name);
762 $self->throw_exception(
763 "No constraint columns, maybe a malformed '$constraint_name' constraint?"
766 $self->throw_exception (
767 'find() expects either a column/value hashref, or a list of values '
768 . "corresponding to the columns of the specified unique constraint '$constraint_name'"
769 ) unless @c_cols == @_;
772 @{$call_cond}{@c_cols} = @_;
776 for my $key (keys %$call_cond) {
778 my $keyref = ref($call_cond->{$key})
780 my $relinfo = $rsrc->relationship_info($key)
782 my $val = delete $call_cond->{$key};
784 next if $keyref eq 'ARRAY'; # has_many for multi_create
786 my $rel_q = $rsrc->_resolve_condition(
787 $relinfo->{cond}, $val, $key, $key
789 die "Can't handle complex relationship conditions in find" if ref($rel_q) ne 'HASH';
790 @related{keys %$rel_q} = values %$rel_q;
794 # relationship conditions take precedence (?)
795 @{$call_cond}{keys %related} = values %related;
797 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
799 if (defined $constraint_name) {
800 $final_cond = $self->_qualify_cond_columns (
802 $self->_build_unique_cond (
810 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
811 # This means that we got here after a merger of relationship conditions
812 # in ::Relationship::Base::search_related (the row method), and furthermore
813 # the relationship is of the 'single' type. This means that the condition
814 # provided by the relationship (already attached to $self) is sufficient,
815 # as there can be only one row in the database that would satisfy the
819 # no key was specified - fall down to heuristics mode:
820 # run through all unique queries registered on the resultset, and
821 # 'OR' all qualifying queries together
822 my (@unique_queries, %seen_column_combinations);
823 for my $c_name ($rsrc->unique_constraint_names) {
824 next if $seen_column_combinations{
825 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
828 push @unique_queries, try {
829 $self->_build_unique_cond ($c_name, $call_cond, 'croak_on_nulls')
833 $final_cond = @unique_queries
834 ? [ map { $self->_qualify_cond_columns($_, $alias) } @unique_queries ]
835 : $self->_non_unique_find_fallback ($call_cond, $attrs)
839 # Run the query, passing the result_class since it should propagate for find
840 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
841 if ($rs->_resolved_attrs->{collapse}) {
843 carp "Query returned more than one row" if $rs->next;
851 # This is a stop-gap method as agreed during the discussion on find() cleanup:
852 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
854 # It is invoked when find() is called in legacy-mode with insufficiently-unique
855 # condition. It is provided for overrides until a saner way forward is devised
857 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
858 # the road. Please adjust your tests accordingly to catch this situation early
859 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
861 # The method will not be removed without an adequately complete replacement
862 # for strict-mode enforcement
863 sub _non_unique_find_fallback {
864 my ($self, $cond, $attrs) = @_;
866 return $self->_qualify_cond_columns(
868 exists $attrs->{alias}
870 : $self->{attrs}{alias}
875 sub _qualify_cond_columns {
876 my ($self, $cond, $alias) = @_;
878 my %aliased = %$cond;
879 for (keys %aliased) {
880 $aliased{"$alias.$_"} = delete $aliased{$_}
887 sub _build_unique_cond {
888 my ($self, $constraint_name, $extra_cond, $croak_on_null) = @_;
890 my @c_cols = $self->result_source->unique_constraint_columns($constraint_name);
892 # combination may fail if $self->{cond} is non-trivial
893 my ($final_cond) = try {
894 $self->_merge_with_rscond ($extra_cond)
899 # trim out everything not in $columns
900 $final_cond = { map {
901 exists $final_cond->{$_}
902 ? ( $_ => $final_cond->{$_} )
906 if (my @missing = grep
907 { ! ($croak_on_null ? defined $final_cond->{$_} : exists $final_cond->{$_}) }
910 $self->throw_exception( sprintf ( "Unable to satisfy requested constraint '%s', no values for column(s): %s",
912 join (', ', map { "'$_'" } @missing),
919 !$ENV{DBIC_NULLABLE_KEY_NOWARN}
921 my @undefs = sort grep { ! defined $final_cond->{$_} } (keys %$final_cond)
923 carp_unique ( sprintf (
924 "NULL/undef values supplied for requested unique constraint '%s' (NULL "
925 . 'values in column(s): %s). This is almost certainly not what you wanted, '
926 . 'though you can set DBIC_NULLABLE_KEY_NOWARN to disable this warning.',
928 join (', ', map { "'$_'" } @undefs),
935 =head2 search_related
939 =item Arguments: $rel_name, $cond?, L<\%attrs?|/ATTRIBUTES>
941 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
945 $new_rs = $cd_rs->search_related('artist', {
949 Searches the specified relationship, optionally specifying a condition and
950 attributes for matching records. See L</ATTRIBUTES> for more information.
952 In list context, C<< ->all() >> is called implicitly on the resultset, thus
953 returning a list of result objects instead. To avoid that, use L</search_related_rs>.
955 See also L</search_related_rs>.
960 return shift->related_resultset(shift)->search(@_);
963 =head2 search_related_rs
965 This method works exactly the same as search_related, except that
966 it guarantees a resultset, even in list context.
970 sub search_related_rs {
971 return shift->related_resultset(shift)->search_rs(@_);
978 =item Arguments: none
980 =item Return Value: L<$cursor|DBIx::Class::Cursor>
984 Returns a storage-driven cursor to the given resultset. See
985 L<DBIx::Class::Cursor> for more information.
992 return $self->{cursor} ||= do {
993 my $attrs = { %{$self->_resolved_attrs } };
994 $self->result_source->storage->select(
995 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
1004 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1006 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1010 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1012 Inflates the first result without creating a cursor if the resultset has
1013 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1016 While this method can take an optional search condition (just like L</search>)
1017 being a fast-code-path it does not recognize search attributes. If you need to
1018 add extra joins or similar, call L</search> and then chain-call L</single> on the
1019 L<DBIx::Class::ResultSet> returned.
1025 As of 0.08100, this method enforces the assumption that the preceding
1026 query returns only one row. If more than one row is returned, you will receive
1029 Query returned more than one row
1031 In this case, you should be using L</next> or L</find> instead, or if you really
1032 know what you are doing, use the L</rows> attribute to explicitly limit the size
1035 This method will also throw an exception if it is called on a resultset prefetching
1036 has_many, as such a prefetch implies fetching multiple rows from the database in
1037 order to assemble the resulting object.
1044 my ($self, $where) = @_;
1046 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1049 my $attrs = { %{$self->_resolved_attrs} };
1051 $self->throw_exception(
1052 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
1053 ) if $attrs->{collapse};
1056 if (defined $attrs->{where}) {
1059 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1060 $where, delete $attrs->{where} ]
1063 $attrs->{where} = $where;
1067 my $data = [ $self->result_source->storage->select_single(
1068 $attrs->{from}, $attrs->{select},
1069 $attrs->{where}, $attrs
1071 return undef unless @$data;
1072 $self->{stashed_rows} = [ $data ];
1073 $self->_construct_objects->[0];
1079 # Recursively collapse the query, accumulating values for each column.
1081 sub _collapse_query {
1082 my ($self, $query, $collapsed) = @_;
1086 if (ref $query eq 'ARRAY') {
1087 foreach my $subquery (@$query) {
1088 next unless ref $subquery; # -or
1089 $collapsed = $self->_collapse_query($subquery, $collapsed);
1092 elsif (ref $query eq 'HASH') {
1093 if (keys %$query and (keys %$query)[0] eq '-and') {
1094 foreach my $subquery (@{$query->{-and}}) {
1095 $collapsed = $self->_collapse_query($subquery, $collapsed);
1099 foreach my $col (keys %$query) {
1100 my $value = $query->{$col};
1101 $collapsed->{$col}{$value}++;
1113 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1115 =item Return Value: L<$resultsetcolumn|DBIx::Class::ResultSetColumn>
1119 my $max_length = $rs->get_column('length')->max;
1121 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1126 my ($self, $column) = @_;
1127 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
1135 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1137 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1141 # WHERE title LIKE '%blue%'
1142 $cd_rs = $rs->search_like({ title => '%blue%'});
1144 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1145 that this is simply a convenience method retained for ex Class::DBI users.
1146 You most likely want to use L</search> with specific operators.
1148 For more information, see L<DBIx::Class::Manual::Cookbook>.
1150 This method is deprecated and will be removed in 0.09. Use L</search()>
1151 instead. An example conversion is:
1153 ->search_like({ foo => 'bar' });
1157 ->search({ foo => { like => 'bar' } });
1164 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1165 .' Instead use ->search({ x => { -like => "y%" } })'
1166 .' (note the outer pair of {}s - they are important!)'
1168 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1169 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1170 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1171 return $class->search($query, { %$attrs });
1178 =item Arguments: $first, $last
1180 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1184 Returns a resultset or object list representing a subset of elements from the
1185 resultset slice is called on. Indexes are from 0, i.e., to get the first
1186 three records, call:
1188 my ($one, $two, $three) = $rs->slice(0, 2);
1193 my ($self, $min, $max) = @_;
1194 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1195 $attrs->{offset} = $self->{attrs}{offset} || 0;
1196 $attrs->{offset} += $min;
1197 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1198 return $self->search(undef, $attrs);
1199 #my $slice = (ref $self)->new($self->result_source, $attrs);
1200 #return (wantarray ? $slice->all : $slice);
1207 =item Arguments: none
1209 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1213 Returns the next element in the resultset (C<undef> is there is none).
1215 Can be used to efficiently iterate over records in the resultset:
1217 my $rs = $schema->resultset('CD')->search;
1218 while (my $cd = $rs->next) {
1222 Note that you need to store the resultset object, and call C<next> on it.
1223 Calling C<< resultset('Table')->next >> repeatedly will always return the
1224 first record from the resultset.
1231 if (my $cache = $self->get_cache) {
1232 $self->{all_cache_position} ||= 0;
1233 return $cache->[$self->{all_cache_position}++];
1236 if ($self->{attrs}{cache}) {
1237 delete $self->{pager};
1238 $self->{all_cache_position} = 1;
1239 return ($self->all)[0];
1242 return shift(@{$self->{stashed_objects}}) if @{ $self->{stashed_objects}||[] };
1244 $self->{stashed_objects} = $self->_construct_objects
1247 return shift @{$self->{stashed_objects}};
1250 # Constructs as many objects as it can in one pass while respecting
1251 # cursor laziness. Several modes of operation:
1253 # * Always builds everything present in @{$self->{stashed_rows}}
1254 # * If called with $fetch_all true - pulls everything off the cursor and
1255 # builds all objects in one pass
1256 # * If $self->_resolved_attrs->{collapse} is true, checks the order_by
1257 # and if the resultset is ordered properly by the left side:
1258 # * Fetches stuff off the cursor until the "master object" changes,
1259 # and saves the last extra row (if any) in @{$self->{stashed_rows}}
1261 # * Just fetches, and collapses/constructs everything as if $fetch_all
1262 # was requested (there is no other way to collapse except for an
1264 # * If no collapse is requested - just get the next row, construct and
1266 sub _construct_objects {
1267 my ($self, $fetch_all) = @_;
1269 my $rsrc = $self->result_source;
1270 my $attrs = $self->_resolved_attrs;
1272 if (!$fetch_all and ! $attrs->{order_by} and $attrs->{collapse}) {
1273 # default order for collapsing unless the user asked for something
1274 $attrs->{order_by} = [ map { join '.', $attrs->{alias}, $_} $rsrc->primary_columns ];
1275 $attrs->{_ordered_for_collapse} = 1;
1276 $attrs->{_order_is_artificial} = 1;
1279 my $cursor = $self->cursor;
1281 # this will be used as both initial raw-row collector AND as a RV of
1282 # _construct_objects. Not regrowing the array twice matters a lot...
1283 # a suprising amount actually
1284 my $rows = (delete $self->{stashed_rows}) || [];
1286 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1287 $rows = [ @$rows, $cursor->all ];
1289 elsif (!$attrs->{collapse}) {
1290 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1291 push @$rows, do { my @r = $cursor->next; @r ? \@r : () }
1295 $attrs->{_ordered_for_collapse} ||= (!$attrs->{order_by}) ? undef : do {
1296 my $st = $rsrc->schema->storage;
1299 ( $st->_extract_order_criteria($attrs->{order_by}) )
1302 my $colinfos = $st->_resolve_column_info($attrs->{from}, \@ord_cols);
1304 for (0 .. $#ord_cols) {
1306 ! $colinfos->{$ord_cols[$_]}
1308 $colinfos->{$ord_cols[$_]}{-result_source} != $rsrc
1310 splice @ord_cols, $_;
1315 # since all we check here are the start of the order_by belonging to the
1316 # top level $rsrc, a present identifying set will mean that the resultset
1317 # is ordered by its leftmost table in a tsable manner
1318 (@ord_cols and $rsrc->_identifying_column_set({ map
1319 { $colinfos->{$_}{-colname} => $colinfos->{$_} }
1324 if ($attrs->{_ordered_for_collapse}) {
1325 push @$rows, do { my @r = $cursor->next; @r ? \@r : () };
1327 # instead of looping over ->next, use ->all in stealth mode
1328 # *without* calling a ->reset afterwards
1329 # FIXME - encapsulation breach, got to be a better way
1330 elsif (! $cursor->{_done}) {
1331 push @$rows, $cursor->all;
1332 $cursor->{_done} = 1;
1337 return undef unless @$rows;
1339 my $res_class = $self->result_class;
1340 my $inflator = $res_class->can ('inflate_result')
1341 or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
1343 my $infmap = $attrs->{as};
1345 if (!$attrs->{collapse} and $attrs->{_single_object_inflation}) {
1346 # construct a much simpler array->hash folder for the one-table cases right here
1348 # FIXME SUBOPTIMAL this is a very very very hot spot
1349 # while rather optimal we can *still* do much better, by
1350 # building a smarter [Row|HRI]::inflate_result(), and
1351 # switch to feeding it data via a much leaner interface
1353 # crude unscientific benchmarking indicated the shortcut eval is not worth it for
1354 # this particular resultset size
1356 my @as_idx = 0..$#$infmap;
1357 for my $r (@$rows) {
1358 $r = $inflator->($res_class, $rsrc, { map { $infmap->[$_] => $r->[$_] } @as_idx } );
1363 '$_ = $inflator->($res_class, $rsrc, { %s }) for @$rows',
1364 join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap )
1369 $self->{_row_parser} ||= eval sprintf 'sub { %s }', $rsrc->_mk_row_parser({
1370 inflate_map => $infmap,
1371 selection => $attrs->{select},
1372 collapse => $attrs->{collapse},
1373 premultiplied => $attrs->{_main_source_premultiplied},
1376 # modify $rows in-place, shrinking/extending as necessary
1377 $self->{_row_parser}->($rows, $fetch_all ? () : (
1378 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1379 sub { my @r = $cursor->next or return; \@r }, # how the collapser gets more rows
1380 ($self->{stashed_rows} = []), # where does it stuff excess
1383 $_ = $inflator->($res_class, $rsrc, @$_) for @$rows;
1387 if ($attrs->{record_filter}) {
1388 $_ = $attrs->{record_filter}->($_) for @$rows;
1394 =head2 result_source
1398 =item Arguments: L<$result_source?|DBIx::Class::ResultSource>
1400 =item Return Value: L<$result_source|DBIx::Class::ResultSource>
1404 An accessor for the primary ResultSource object from which this ResultSet
1411 =item Arguments: $result_class?
1413 =item Return Value: $result_class
1417 An accessor for the class to use when creating result objects. Defaults to
1418 C<< result_source->result_class >> - which in most cases is the name of the
1419 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1421 Note that changing the result_class will also remove any components
1422 that were originally loaded in the source class via
1423 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1424 in the original source class will not run.
1429 my ($self, $result_class) = @_;
1430 if ($result_class) {
1431 unless (ref $result_class) { # don't fire this for an object
1432 $self->ensure_class_loaded($result_class);
1434 $self->_result_class($result_class);
1435 # THIS LINE WOULD BE A BUG - this accessor specifically exists to
1436 # permit the user to set result class on one result set only; it only
1437 # chains if provided to search()
1438 #$self->{attrs}{result_class} = $result_class if ref $self;
1440 $self->_result_class;
1447 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1449 =item Return Value: $count
1453 Performs an SQL C<COUNT> with the same query as the resultset was built
1454 with to find the number of elements. Passing arguments is equivalent to
1455 C<< $rs->search ($cond, \%attrs)->count >>
1461 return $self->search(@_)->count if @_ and defined $_[0];
1462 return scalar @{ $self->get_cache } if $self->get_cache;
1464 my $attrs = { %{ $self->_resolved_attrs } };
1466 # this is a little optimization - it is faster to do the limit
1467 # adjustments in software, instead of a subquery
1468 my ($rows, $offset) = delete @{$attrs}{qw/rows offset/};
1471 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1472 $crs = $self->_count_subq_rs ($attrs);
1475 $crs = $self->_count_rs ($attrs);
1477 my $count = $crs->next;
1479 $count -= $offset if $offset;
1480 $count = $rows if $rows and $rows < $count;
1481 $count = 0 if ($count < 0);
1490 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1492 =item Return Value: L<$count_rs|DBIx::Class::ResultSetColumn>
1496 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1497 This can be very handy for subqueries:
1499 ->search( { amount => $some_rs->count_rs->as_query } )
1501 As with regular resultsets the SQL query will be executed only after
1502 the resultset is accessed via L</next> or L</all>. That would return
1503 the same single value obtainable via L</count>.
1509 return $self->search(@_)->count_rs if @_;
1511 # this may look like a lack of abstraction (count() does about the same)
1512 # but in fact an _rs *must* use a subquery for the limits, as the
1513 # software based limiting can not be ported if this $rs is to be used
1514 # in a subquery itself (i.e. ->as_query)
1515 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1516 return $self->_count_subq_rs;
1519 return $self->_count_rs;
1524 # returns a ResultSetColumn object tied to the count query
1527 my ($self, $attrs) = @_;
1529 my $rsrc = $self->result_source;
1530 $attrs ||= $self->_resolved_attrs;
1532 my $tmp_attrs = { %$attrs };
1533 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1534 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1536 # overwrite the selector (supplied by the storage)
1537 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $attrs);
1538 $tmp_attrs->{as} = 'count';
1540 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1546 # same as above but uses a subquery
1548 sub _count_subq_rs {
1549 my ($self, $attrs) = @_;
1551 my $rsrc = $self->result_source;
1552 $attrs ||= $self->_resolved_attrs;
1554 my $sub_attrs = { %$attrs };
1555 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1556 delete @{$sub_attrs}{qw/collapse columns as select _prefetch_selector_range order_by for/};
1558 # if we multi-prefetch we group_by something unique, as this is what we would
1559 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1560 if ( $attrs->{collapse} ) {
1561 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1562 $rsrc->_identifying_column_set || $self->throw_exception(
1563 'Unable to construct a unique group_by criteria properly collapsing the '
1564 . 'has_many prefetch before count()'
1569 # Calculate subquery selector
1570 if (my $g = $sub_attrs->{group_by}) {
1572 my $sql_maker = $rsrc->storage->sql_maker;
1574 # necessary as the group_by may refer to aliased functions
1576 for my $sel (@{$attrs->{select}}) {
1577 $sel_index->{$sel->{-as}} = $sel
1578 if (ref $sel eq 'HASH' and $sel->{-as});
1581 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1582 # also look for named aggregates referred in the having clause
1583 # having often contains scalarrefs - thus parse it out entirely
1585 if ($attrs->{having}) {
1586 local $sql_maker->{having_bind};
1587 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1588 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1589 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1590 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1591 # if we don't unset it we screw up retarded but unfortunately working
1592 # 'MAX(foo.bar)' => { '>', 3 }
1593 $sql_maker->{name_sep} = '';
1596 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1598 my $having_sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1601 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1602 # and if all fails for an utterly naive quoted scalar-with-function
1603 while ($having_sql =~ /
1604 $rquote $sep $lquote (.+?) $rquote
1606 [\s,] \w+ \. (\w+) [\s,]
1608 [\s,] $lquote (.+?) $rquote [\s,]
1610 my $part = $1 || $2 || $3; # one of them matched if we got here
1611 unless ($seen_having{$part}++) {
1618 my $colpiece = $sel_index->{$_} || $_;
1620 # unqualify join-based group_by's. Arcane but possible query
1621 # also horrible horrible hack to alias a column (not a func.)
1622 # (probably need to introduce SQLA syntax)
1623 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1626 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1628 push @{$sub_attrs->{select}}, $colpiece;
1632 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1633 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1636 return $rsrc->resultset_class
1637 ->new ($rsrc, $sub_attrs)
1639 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1640 ->get_column ('count');
1647 =head2 count_literal
1649 B<CAVEAT>: C<count_literal> is provided for Class::DBI compatibility and
1650 should only be used in that context. See L</search_literal> for further info.
1654 =item Arguments: $sql_fragment, @standalone_bind_values
1656 =item Return Value: $count
1660 Counts the results in a literal query. Equivalent to calling L</search_literal>
1661 with the passed arguments, then L</count>.
1665 sub count_literal { shift->search_literal(@_)->count; }
1671 =item Arguments: none
1673 =item Return Value: L<@result_objs|DBIx::Class::Manual::ResultClass>
1677 Returns all elements in the resultset.
1684 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1687 delete @{$self}{qw/stashed_rows stashed_objects/};
1689 if (my $c = $self->get_cache) {
1693 $self->cursor->reset;
1695 my $objs = $self->_construct_objects('fetch_all') || [];
1697 $self->set_cache($objs) if $self->{attrs}{cache};
1706 =item Arguments: none
1708 =item Return Value: $self
1712 Resets the resultset's cursor, so you can iterate through the elements again.
1713 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1721 delete @{$self}{qw/stashed_rows stashed_objects/};
1722 $self->{all_cache_position} = 0;
1723 $self->cursor->reset;
1731 =item Arguments: none
1733 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1737 L<Resets|/reset> the resultset (causing a fresh query to storage) and returns
1738 an object for the first result (or C<undef> if the resultset is empty).
1743 return $_[0]->reset->next;
1749 # Determines whether and what type of subquery is required for the $rs operation.
1750 # If grouping is necessary either supplies its own, or verifies the current one
1751 # After all is done delegates to the proper storage method.
1753 sub _rs_update_delete {
1754 my ($self, $op, $values) = @_;
1756 my $rsrc = $self->result_source;
1757 my $storage = $rsrc->schema->storage;
1759 my $attrs = { %{$self->_resolved_attrs} };
1761 my $join_classifications;
1762 my $existing_group_by = delete $attrs->{group_by};
1764 # do we need a subquery for any reason?
1766 defined $existing_group_by
1768 # if {from} is unparseable wrap a subq
1769 ref($attrs->{from}) ne 'ARRAY'
1771 # limits call for a subq
1772 $self->_has_resolved_attr(qw/rows offset/)
1775 # simplify the joinmap, so we can further decide if a subq is necessary
1776 if (!$needs_subq and @{$attrs->{from}} > 1) {
1777 $attrs->{from} = $storage->_prune_unused_joins ($attrs->{from}, $attrs->{select}, $self->{cond}, $attrs);
1779 # check if there are any joins left after the prune
1780 if ( @{$attrs->{from}} > 1 ) {
1781 $join_classifications = $storage->_resolve_aliastypes_from_select_args (
1782 [ @{$attrs->{from}}[1 .. $#{$attrs->{from}}] ],
1788 # any non-pruneable joins imply subq
1789 $needs_subq = scalar keys %{ $join_classifications->{restricting} || {} };
1793 # check if the head is composite (by now all joins are thrown out unless $needs_subq)
1795 (ref $attrs->{from}[0]) ne 'HASH'
1797 ref $attrs->{from}[0]{ $attrs->{from}[0]{-alias} }
1801 # do we need anything like a subquery?
1802 if (! $needs_subq) {
1803 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1804 # a condition containing 'me' or other table prefixes will not work
1805 # at all. Tell SQLMaker to dequalify idents via a gross hack.
1807 my $sqla = $rsrc->storage->sql_maker;
1808 local $sqla->{_dequalify_idents} = 1;
1809 \[ $sqla->_recurse_where($self->{cond}) ];
1813 # we got this far - means it is time to wrap a subquery
1814 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1816 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1822 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1823 delete $attrs->{$_} for qw/collapse select _prefetch_selector_range as/;
1824 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1825 $attrs->{group_by} = \ ''; # FIXME - this is an evil hack, it causes the optimiser to kick in and throw away the LEFT joins
1826 my $subrs = (ref $self)->new($rsrc, $attrs);
1828 if (@$idcols == 1) {
1829 $cond = { $idcols->[0] => { -in => $subrs->as_query } };
1831 elsif ($storage->_use_multicolumn_in) {
1832 # no syntax for calling this properly yet
1833 # !!! EXPERIMENTAL API !!! WILL CHANGE !!!
1834 $cond = $storage->sql_maker->_where_op_multicolumn_in (
1835 $idcols, # how do I convey a list of idents...? can binds reside on lhs?
1840 # if all else fails - get all primary keys and operate over a ORed set
1841 # wrap in a transaction for consistency
1842 # this is where the group_by/multiplication starts to matter
1846 keys %{ $join_classifications->{multiplying} || {} }
1848 # make sure if there is a supplied group_by it matches the columns compiled above
1849 # perfectly. Anything else can not be sanely executed on most databases so croak
1850 # right then and there
1851 if ($existing_group_by) {
1852 my @current_group_by = map
1853 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1858 join ("\x00", sort @current_group_by)
1860 join ("\x00", sort @{$attrs->{columns}} )
1862 $self->throw_exception (
1863 "You have just attempted a $op operation on a resultset which does group_by"
1864 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1865 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1866 . ' kind of queries. Please retry the operation with a modified group_by or'
1867 . ' without using one at all.'
1872 $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
1875 $guard = $storage->txn_scope_guard;
1878 for my $row ($subrs->cursor->all) {
1880 { $idcols->[$_] => $row->[$_] }
1887 my $res = $storage->$op (
1889 $op eq 'update' ? $values : (),
1893 $guard->commit if $guard;
1902 =item Arguments: \%values
1904 =item Return Value: $underlying_storage_rv
1908 Sets the specified columns in the resultset to the supplied values in a
1909 single query. Note that this will not run any accessor/set_column/update
1910 triggers, nor will it update any result object instances derived from this
1911 resultset (this includes the contents of the L<resultset cache|/set_cache>
1912 if any). See L</update_all> if you need to execute any on-update
1913 triggers or cascades defined either by you or a
1914 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1916 The return value is a pass through of what the underlying
1917 storage backend returned, and may vary. See L<DBI/execute> for the most
1922 Note that L</update> does not process/deflate any of the values passed in.
1923 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
1924 ensure manually that any value passed to this method will stringify to
1925 something the RDBMS knows how to deal with. A notable example is the
1926 handling of L<DateTime> objects, for more info see:
1927 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
1932 my ($self, $values) = @_;
1933 $self->throw_exception('Values for update must be a hash')
1934 unless ref $values eq 'HASH';
1936 return $self->_rs_update_delete ('update', $values);
1943 =item Arguments: \%values
1945 =item Return Value: 1
1949 Fetches all objects and updates them one at a time via
1950 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
1951 triggers, while L</update> will not.
1956 my ($self, $values) = @_;
1957 $self->throw_exception('Values for update_all must be a hash')
1958 unless ref $values eq 'HASH';
1960 my $guard = $self->result_source->schema->txn_scope_guard;
1961 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
1970 =item Arguments: none
1972 =item Return Value: $underlying_storage_rv
1976 Deletes the rows matching this resultset in a single query. Note that this
1977 will not run any delete triggers, nor will it alter the
1978 L<in_storage|DBIx::Class::Row/in_storage> status of any result object instances
1979 derived from this resultset (this includes the contents of the
1980 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
1981 execute any on-delete triggers or cascades defined either by you or a
1982 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1984 The return value is a pass through of what the underlying storage backend
1985 returned, and may vary. See L<DBI/execute> for the most common case.
1991 $self->throw_exception('delete does not accept any arguments')
1994 return $self->_rs_update_delete ('delete');
2001 =item Arguments: none
2003 =item Return Value: 1
2007 Fetches all objects and deletes them one at a time via
2008 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2009 triggers, while L</delete> will not.
2015 $self->throw_exception('delete_all does not accept any arguments')
2018 my $guard = $self->result_source->schema->txn_scope_guard;
2019 $_->delete for $self->all;
2028 =item Arguments: [ \@column_list, \@row_values+ ] | [ \%col_data+ ]
2030 =item Return Value: L<\@result_objects|DBIx::Class::Manual::ResultClass> (scalar context) | L<@result_objects|DBIx::Class::Manual::ResultClass> (list context)
2034 Accepts either an arrayref of hashrefs or alternatively an arrayref of
2041 The context of this method call has an important effect on what is
2042 submitted to storage. In void context data is fed directly to fastpath
2043 insertion routines provided by the underlying storage (most often
2044 L<DBI/execute_for_fetch>), bypassing the L<new|DBIx::Class::Row/new> and
2045 L<insert|DBIx::Class::Row/insert> calls on the
2046 L<Result|DBIx::Class::Manual::ResultClass> class, including any
2047 augmentation of these methods provided by components. For example if you
2048 are using something like L<DBIx::Class::UUIDColumns> to create primary
2049 keys for you, you will find that your PKs are empty. In this case you
2050 will have to explicitly force scalar or list context in order to create
2055 In non-void (scalar or list) context, this method is simply a wrapper
2056 for L</create>. Depending on list or scalar context either a list of
2057 L<Result|DBIx::Class::Manual::ResultClass> objects or an arrayref
2058 containing these objects is returned.
2060 When supplying data in "arrayref of arrayrefs" invocation style, the
2061 first element should be a list of column names and each subsequent
2062 element should be a data value in the earlier specified column order.
2065 $Arstist_rs->populate([
2066 [ qw( artistid name ) ],
2067 [ 100, 'A Formally Unknown Singer' ],
2068 [ 101, 'A singer that jumped the shark two albums ago' ],
2069 [ 102, 'An actually cool singer' ],
2072 For the arrayref of hashrefs style each hashref should be a structure
2073 suitable for passing to L</create>. Multi-create is also permitted with
2076 $schema->resultset("Artist")->populate([
2077 { artistid => 4, name => 'Manufactured Crap', cds => [
2078 { title => 'My First CD', year => 2006 },
2079 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2082 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2083 { title => 'My parents sold me to a record company', year => 2005 },
2084 { title => 'Why Am I So Ugly?', year => 2006 },
2085 { title => 'I Got Surgery and am now Popular', year => 2007 }
2090 If you attempt a void-context multi-create as in the example above (each
2091 Artist also has the related list of CDs), and B<do not> supply the
2092 necessary autoinc foreign key information, this method will proxy to the
2093 less efficient L</create>, and then throw the Result objects away. In this
2094 case there are obviously no benefits to using this method over L</create>.
2101 # cruft placed in standalone method
2102 my $data = $self->_normalize_populate_args(@_);
2104 return unless @$data;
2106 if(defined wantarray) {
2107 my @created = map { $self->create($_) } @$data;
2108 return wantarray ? @created : \@created;
2111 my $first = $data->[0];
2113 # if a column is a registered relationship, and is a non-blessed hash/array, consider
2114 # it relationship data
2115 my (@rels, @columns);
2116 my $rsrc = $self->result_source;
2117 my $rels = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2118 for (keys %$first) {
2119 my $ref = ref $first->{$_};
2120 $rels->{$_} && ($ref eq 'ARRAY' or $ref eq 'HASH')
2126 my @pks = $rsrc->primary_columns;
2128 ## do the belongs_to relationships
2129 foreach my $index (0..$#$data) {
2131 # delegate to create() for any dataset without primary keys with specified relationships
2132 if (grep { !defined $data->[$index]->{$_} } @pks ) {
2134 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
2135 my @ret = $self->populate($data);
2141 foreach my $rel (@rels) {
2142 next unless ref $data->[$index]->{$rel} eq "HASH";
2143 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
2144 my ($reverse_relname, $reverse_relinfo) = %{$rsrc->reverse_relationship_info($rel)};
2145 my $related = $result->result_source->_resolve_condition(
2146 $reverse_relinfo->{cond},
2152 delete $data->[$index]->{$rel};
2153 $data->[$index] = {%{$data->[$index]}, %$related};
2155 push @columns, keys %$related if $index == 0;
2159 ## inherit the data locked in the conditions of the resultset
2160 my ($rs_data) = $self->_merge_with_rscond({});
2161 delete @{$rs_data}{@columns};
2163 ## do bulk insert on current row
2164 $rsrc->storage->insert_bulk(
2166 [@columns, keys %$rs_data],
2167 [ map { [ @$_{@columns}, values %$rs_data ] } @$data ],
2170 ## do the has_many relationships
2171 foreach my $item (@$data) {
2175 foreach my $rel (@rels) {
2176 next unless ref $item->{$rel} eq "ARRAY" && @{ $item->{$rel} };
2178 $main_row ||= $self->new_result({map { $_ => $item->{$_} } @pks});
2180 my $child = $main_row->$rel;
2182 my $related = $child->result_source->_resolve_condition(
2183 $rels->{$rel}{cond},
2189 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
2190 my @populate = map { {%$_, %$related} } @rows_to_add;
2192 $child->populate( \@populate );
2199 # populate() argumnets went over several incarnations
2200 # What we ultimately support is AoH
2201 sub _normalize_populate_args {
2202 my ($self, $arg) = @_;
2204 if (ref $arg eq 'ARRAY') {
2208 elsif (ref $arg->[0] eq 'HASH') {
2211 elsif (ref $arg->[0] eq 'ARRAY') {
2213 my @colnames = @{$arg->[0]};
2214 foreach my $values (@{$arg}[1 .. $#$arg]) {
2215 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
2221 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2228 =item Arguments: none
2230 =item Return Value: L<$pager|Data::Page>
2234 Returns a L<Data::Page> object for the current resultset. Only makes
2235 sense for queries with a C<page> attribute.
2237 To get the full count of entries for a paged resultset, call
2238 C<total_entries> on the L<Data::Page> object.
2245 return $self->{pager} if $self->{pager};
2247 my $attrs = $self->{attrs};
2248 if (!defined $attrs->{page}) {
2249 $self->throw_exception("Can't create pager for non-paged rs");
2251 elsif ($attrs->{page} <= 0) {
2252 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2254 $attrs->{rows} ||= 10;
2256 # throw away the paging flags and re-run the count (possibly
2257 # with a subselect) to get the real total count
2258 my $count_attrs = { %$attrs };
2259 delete @{$count_attrs}{qw/rows offset page pager/};
2261 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2263 require DBIx::Class::ResultSet::Pager;
2264 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2265 sub { $total_rs->count }, #lazy-get the total
2267 $self->{attrs}{page},
2275 =item Arguments: $page_number
2277 =item Return Value: L<$resultset|/search>
2281 Returns a resultset for the $page_number page of the resultset on which page
2282 is called, where each page contains a number of rows equal to the 'rows'
2283 attribute set on the resultset (10 by default).
2288 my ($self, $page) = @_;
2289 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2296 =item Arguments: \%col_data
2298 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2302 Creates a new result object in the resultset's result class and returns
2303 it. The row is not inserted into the database at this point, call
2304 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2305 will tell you whether the result object has been inserted or not.
2307 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2312 my ($self, $values) = @_;
2314 $self->throw_exception( "new_result takes only one argument - a hashref of values" )
2317 $self->throw_exception( "new_result expects a hashref" )
2318 unless (ref $values eq 'HASH');
2320 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2324 @$cols_from_relations
2325 ? (-cols_from_relations => $cols_from_relations)
2327 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2330 return $self->result_class->new(\%new);
2333 # _merge_with_rscond
2335 # Takes a simple hash of K/V data and returns its copy merged with the
2336 # condition already present on the resultset. Additionally returns an
2337 # arrayref of value/condition names, which were inferred from related
2338 # objects (this is needed for in-memory related objects)
2339 sub _merge_with_rscond {
2340 my ($self, $data) = @_;
2342 my (%new_data, @cols_from_relations);
2344 my $alias = $self->{attrs}{alias};
2346 if (! defined $self->{cond}) {
2347 # just massage $data below
2349 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
2350 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
2351 @cols_from_relations = keys %new_data;
2353 elsif (ref $self->{cond} ne 'HASH') {
2354 $self->throw_exception(
2355 "Can't abstract implicit construct, resultset condition not a hash"
2359 # precendence must be given to passed values over values inherited from
2360 # the cond, so the order here is important.
2361 my $collapsed_cond = $self->_collapse_cond($self->{cond});
2362 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
2364 while ( my($col, $value) = each %implied ) {
2365 my $vref = ref $value;
2371 (keys %$value)[0] eq '='
2373 $new_data{$col} = $value->{'='};
2375 elsif( !$vref or $vref eq 'SCALAR' or blessed($value) ) {
2376 $new_data{$col} = $value;
2383 %{ $self->_remove_alias($data, $alias) },
2386 return (\%new_data, \@cols_from_relations);
2389 # _has_resolved_attr
2391 # determines if the resultset defines at least one
2392 # of the attributes supplied
2394 # used to determine if a subquery is neccessary
2396 # supports some virtual attributes:
2398 # This will scan for any joins being present on the resultset.
2399 # It is not a mere key-search but a deep inspection of {from}
2402 sub _has_resolved_attr {
2403 my ($self, @attr_names) = @_;
2405 my $attrs = $self->_resolved_attrs;
2409 for my $n (@attr_names) {
2410 if (grep { $n eq $_ } (qw/-join/) ) {
2411 $extra_checks{$n}++;
2415 my $attr = $attrs->{$n};
2417 next if not defined $attr;
2419 if (ref $attr eq 'HASH') {
2420 return 1 if keys %$attr;
2422 elsif (ref $attr eq 'ARRAY') {
2430 # a resolved join is expressed as a multi-level from
2432 $extra_checks{-join}
2434 ref $attrs->{from} eq 'ARRAY'
2436 @{$attrs->{from}} > 1
2444 # Recursively collapse the condition.
2446 sub _collapse_cond {
2447 my ($self, $cond, $collapsed) = @_;
2451 if (ref $cond eq 'ARRAY') {
2452 foreach my $subcond (@$cond) {
2453 next unless ref $subcond; # -or
2454 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2457 elsif (ref $cond eq 'HASH') {
2458 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2459 foreach my $subcond (@{$cond->{-and}}) {
2460 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2464 foreach my $col (keys %$cond) {
2465 my $value = $cond->{$col};
2466 $collapsed->{$col} = $value;
2476 # Remove the specified alias from the specified query hash. A copy is made so
2477 # the original query is not modified.
2480 my ($self, $query, $alias) = @_;
2482 my %orig = %{ $query || {} };
2485 foreach my $key (keys %orig) {
2487 $unaliased{$key} = $orig{$key};
2490 $unaliased{$1} = $orig{$key}
2491 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2501 =item Arguments: none
2503 =item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
2507 Returns the SQL query and bind vars associated with the invocant.
2509 This is generally used as the RHS for a subquery.
2516 my $attrs = { %{ $self->_resolved_attrs } };
2521 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2522 # $sql also has no wrapping parenthesis in list ctx
2524 my $sqlbind = $self->result_source->storage
2525 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2534 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2536 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2540 my $artist = $schema->resultset('Artist')->find_or_new(
2541 { artist => 'fred' }, { key => 'artists' });
2543 $cd->cd_to_producer->find_or_new({ producer => $producer },
2544 { key => 'primary });
2546 Find an existing record from this resultset using L</find>. if none exists,
2547 instantiate a new result object and return it. The object will not be saved
2548 into your storage until you call L<DBIx::Class::Row/insert> on it.
2550 You most likely want this method when looking for existing rows using a unique
2551 constraint that is not the primary key, or looking for related rows.
2553 If you want objects to be saved immediately, use L</find_or_create> instead.
2555 B<Note>: Make sure to read the documentation of L</find> and understand the
2556 significance of the C<key> attribute, as its lack may skew your search, and
2557 subsequently result in spurious new objects.
2559 B<Note>: Take care when using C<find_or_new> with a table having
2560 columns with default values that you intend to be automatically
2561 supplied by the database (e.g. an auto_increment primary key column).
2562 In normal usage, the value of such columns should NOT be included at
2563 all in the call to C<find_or_new>, even when set to C<undef>.
2569 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2570 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2571 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2574 return $self->new_result($hash);
2581 =item Arguments: \%col_data
2583 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2587 Attempt to create a single new row or a row with multiple related rows
2588 in the table represented by the resultset (and related tables). This
2589 will not check for duplicate rows before inserting, use
2590 L</find_or_create> to do that.
2592 To create one row for this resultset, pass a hashref of key/value
2593 pairs representing the columns of the table and the values you wish to
2594 store. If the appropriate relationships are set up, foreign key fields
2595 can also be passed an object representing the foreign row, and the
2596 value will be set to its primary key.
2598 To create related objects, pass a hashref of related-object column values
2599 B<keyed on the relationship name>. If the relationship is of type C<multi>
2600 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2601 The process will correctly identify columns holding foreign keys, and will
2602 transparently populate them from the keys of the corresponding relation.
2603 This can be applied recursively, and will work correctly for a structure
2604 with an arbitrary depth and width, as long as the relationships actually
2605 exists and the correct column data has been supplied.
2607 Instead of hashrefs of plain related data (key/value pairs), you may
2608 also pass new or inserted objects. New objects (not inserted yet, see
2609 L</new_result>), will be inserted into their appropriate tables.
2611 Effectively a shortcut for C<< ->new_result(\%col_data)->insert >>.
2613 Example of creating a new row.
2615 $person_rs->create({
2616 name=>"Some Person",
2617 email=>"somebody@someplace.com"
2620 Example of creating a new row and also creating rows in a related C<has_many>
2621 or C<has_one> resultset. Note Arrayref.
2624 { artistid => 4, name => 'Manufactured Crap', cds => [
2625 { title => 'My First CD', year => 2006 },
2626 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2631 Example of creating a new row and also creating a row in a related
2632 C<belongs_to> resultset. Note Hashref.
2635 title=>"Music for Silly Walks",
2638 name=>"Silly Musician",
2646 When subclassing ResultSet never attempt to override this method. Since
2647 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2648 lot of the internals simply never call it, so your override will be
2649 bypassed more often than not. Override either L<DBIx::Class::Row/new>
2650 or L<DBIx::Class::Row/insert> depending on how early in the
2651 L</create> process you need to intervene. See also warning pertaining to
2659 my ($self, $attrs) = @_;
2660 $self->throw_exception( "create needs a hashref" )
2661 unless ref $attrs eq 'HASH';
2662 return $self->new_result($attrs)->insert;
2665 =head2 find_or_create
2669 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2671 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2675 $cd->cd_to_producer->find_or_create({ producer => $producer },
2676 { key => 'primary' });
2678 Tries to find a record based on its primary key or unique constraints; if none
2679 is found, creates one and returns that instead.
2681 my $cd = $schema->resultset('CD')->find_or_create({
2683 artist => 'Massive Attack',
2684 title => 'Mezzanine',
2688 Also takes an optional C<key> attribute, to search by a specific key or unique
2689 constraint. For example:
2691 my $cd = $schema->resultset('CD')->find_or_create(
2693 artist => 'Massive Attack',
2694 title => 'Mezzanine',
2696 { key => 'cd_artist_title' }
2699 B<Note>: Make sure to read the documentation of L</find> and understand the
2700 significance of the C<key> attribute, as its lack may skew your search, and
2701 subsequently result in spurious row creation.
2703 B<Note>: Because find_or_create() reads from the database and then
2704 possibly inserts based on the result, this method is subject to a race
2705 condition. Another process could create a record in the table after
2706 the find has completed and before the create has started. To avoid
2707 this problem, use find_or_create() inside a transaction.
2709 B<Note>: Take care when using C<find_or_create> with a table having
2710 columns with default values that you intend to be automatically
2711 supplied by the database (e.g. an auto_increment primary key column).
2712 In normal usage, the value of such columns should NOT be included at
2713 all in the call to C<find_or_create>, even when set to C<undef>.
2715 See also L</find> and L</update_or_create>. For information on how to declare
2716 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2718 If you need to know if an existing row was found or a new one created use
2719 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2720 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2723 my $cd = $schema->resultset('CD')->find_or_new({
2725 artist => 'Massive Attack',
2726 title => 'Mezzanine',
2730 if( !$cd->in_storage ) {
2737 sub find_or_create {
2739 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2740 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2741 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2744 return $self->create($hash);
2747 =head2 update_or_create
2751 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2753 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2757 $resultset->update_or_create({ col => $val, ... });
2759 Like L</find_or_create>, but if a row is found it is immediately updated via
2760 C<< $found_row->update (\%col_data) >>.
2763 Takes an optional C<key> attribute to search on a specific unique constraint.
2766 # In your application
2767 my $cd = $schema->resultset('CD')->update_or_create(
2769 artist => 'Massive Attack',
2770 title => 'Mezzanine',
2773 { key => 'cd_artist_title' }
2776 $cd->cd_to_producer->update_or_create({
2777 producer => $producer,
2783 B<Note>: Make sure to read the documentation of L</find> and understand the
2784 significance of the C<key> attribute, as its lack may skew your search, and
2785 subsequently result in spurious row creation.
2787 B<Note>: Take care when using C<update_or_create> with a table having
2788 columns with default values that you intend to be automatically
2789 supplied by the database (e.g. an auto_increment primary key column).
2790 In normal usage, the value of such columns should NOT be included at
2791 all in the call to C<update_or_create>, even when set to C<undef>.
2793 See also L</find> and L</find_or_create>. For information on how to declare
2794 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2796 If you need to know if an existing row was updated or a new one created use
2797 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2798 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2803 sub update_or_create {
2805 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2806 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2808 my $row = $self->find($cond, $attrs);
2810 $row->update($cond);
2814 return $self->create($cond);
2817 =head2 update_or_new
2821 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2823 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2827 $resultset->update_or_new({ col => $val, ... });
2829 Like L</find_or_new> but if a row is found it is immediately updated via
2830 C<< $found_row->update (\%col_data) >>.
2834 # In your application
2835 my $cd = $schema->resultset('CD')->update_or_new(
2837 artist => 'Massive Attack',
2838 title => 'Mezzanine',
2841 { key => 'cd_artist_title' }
2844 if ($cd->in_storage) {
2845 # the cd was updated
2848 # the cd is not yet in the database, let's insert it
2852 B<Note>: Make sure to read the documentation of L</find> and understand the
2853 significance of the C<key> attribute, as its lack may skew your search, and
2854 subsequently result in spurious new objects.
2856 B<Note>: Take care when using C<update_or_new> with a table having
2857 columns with default values that you intend to be automatically
2858 supplied by the database (e.g. an auto_increment primary key column).
2859 In normal usage, the value of such columns should NOT be included at
2860 all in the call to C<update_or_new>, even when set to C<undef>.
2862 See also L</find>, L</find_or_create> and L</find_or_new>.
2868 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2869 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2871 my $row = $self->find( $cond, $attrs );
2872 if ( defined $row ) {
2873 $row->update($cond);
2877 return $self->new_result($cond);
2884 =item Arguments: none
2886 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass> | undef
2890 Gets the contents of the cache for the resultset, if the cache is set.
2892 The cache is populated either by using the L</prefetch> attribute to
2893 L</search> or by calling L</set_cache>.
2905 =item Arguments: L<\@result_objs|DBIx::Class::Manual::ResultClass>
2907 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass>
2911 Sets the contents of the cache for the resultset. Expects an arrayref
2912 of objects of the same class as those produced by the resultset. Note that
2913 if the cache is set, the resultset will return the cached objects rather
2914 than re-querying the database even if the cache attr is not set.
2916 The contents of the cache can also be populated by using the
2917 L</prefetch> attribute to L</search>.
2922 my ( $self, $data ) = @_;
2923 $self->throw_exception("set_cache requires an arrayref")
2924 if defined($data) && (ref $data ne 'ARRAY');
2925 $self->{all_cache} = $data;
2932 =item Arguments: none
2934 =item Return Value: undef
2938 Clears the cache for the resultset.
2943 shift->set_cache(undef);
2950 =item Arguments: none
2952 =item Return Value: true, if the resultset has been paginated
2960 return !!$self->{attrs}{page};
2967 =item Arguments: none
2969 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2977 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
2980 =head2 related_resultset
2984 =item Arguments: $rel_name
2986 =item Return Value: L<$resultset|/search>
2990 Returns a related resultset for the supplied relationship name.
2992 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2996 sub related_resultset {
2997 my ($self, $rel) = @_;
2999 $self->{related_resultsets} ||= {};
3000 return $self->{related_resultsets}{$rel} ||= do {
3001 my $rsrc = $self->result_source;
3002 my $rel_info = $rsrc->relationship_info($rel);
3004 $self->throw_exception(
3005 "search_related: result source '" . $rsrc->source_name .
3006 "' has no such relationship $rel")
3009 my $attrs = $self->_chain_relationship($rel);
3011 my $join_count = $attrs->{seen_join}{$rel};
3013 my $alias = $self->result_source->storage
3014 ->relname_to_table_alias($rel, $join_count);
3016 # since this is search_related, and we already slid the select window inwards
3017 # (the select/as attrs were deleted in the beginning), we need to flip all
3018 # left joins to inner, so we get the expected results
3019 # read the comment on top of the actual function to see what this does
3020 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
3023 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3024 delete @{$attrs}{qw(result_class alias)};
3028 if (my $cache = $self->get_cache) {
3029 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
3030 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache||[]} }
3035 my $rel_source = $rsrc->related_source($rel);
3039 # The reason we do this now instead of passing the alias to the
3040 # search_rs below is that if you wrap/overload resultset on the
3041 # source you need to know what alias it's -going- to have for things
3042 # to work sanely (e.g. RestrictWithObject wants to be able to add
3043 # extra query restrictions, and these may need to be $alias.)
3045 my $rel_attrs = $rel_source->resultset_attributes;
3046 local $rel_attrs->{alias} = $alias;
3048 $rel_source->resultset
3052 where => $attrs->{where},
3055 $new->set_cache($new_cache) if $new_cache;
3060 =head2 current_source_alias
3064 =item Arguments: none
3066 =item Return Value: $source_alias
3070 Returns the current table alias for the result source this resultset is built
3071 on, that will be used in the SQL query. Usually it is C<me>.
3073 Currently the source alias that refers to the result set returned by a
3074 L</search>/L</find> family method depends on how you got to the resultset: it's
3075 C<me> by default, but eg. L</search_related> aliases it to the related result
3076 source name (and keeps C<me> referring to the original result set). The long
3077 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3078 (and make this method unnecessary).
3080 Thus it's currently necessary to use this method in predefined queries (see
3081 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3082 source alias of the current result set:
3084 # in a result set class
3086 my ($self, $user) = @_;
3088 my $me = $self->current_source_alias;
3090 return $self->search({
3091 "$me.modified" => $user->id,
3097 sub current_source_alias {
3098 return (shift->{attrs} || {})->{alias} || 'me';
3101 =head2 as_subselect_rs
3105 =item Arguments: none
3107 =item Return Value: L<$resultset|/search>
3111 Act as a barrier to SQL symbols. The resultset provided will be made into a
3112 "virtual view" by including it as a subquery within the from clause. From this
3113 point on, any joined tables are inaccessible to ->search on the resultset (as if
3114 it were simply where-filtered without joins). For example:
3116 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3118 # 'x' now pollutes the query namespace
3120 # So the following works as expected
3121 my $ok_rs = $rs->search({'x.other' => 1});
3123 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3124 # def) we look for one row with contradictory terms and join in another table
3125 # (aliased 'x_2') which we never use
3126 my $broken_rs = $rs->search({'x.name' => 'def'});
3128 my $rs2 = $rs->as_subselect_rs;
3130 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3131 my $not_joined_rs = $rs2->search({'x.other' => 1});
3133 # works as expected: finds a 'table' row related to two x rows (abc and def)
3134 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3136 Another example of when one might use this would be to select a subset of
3137 columns in a group by clause:
3139 my $rs = $schema->resultset('Bar')->search(undef, {
3140 group_by => [qw{ id foo_id baz_id }],
3141 })->as_subselect_rs->search(undef, {
3142 columns => [qw{ id foo_id }]
3145 In the above example normally columns would have to be equal to the group by,
3146 but because we isolated the group by into a subselect the above works.
3150 sub as_subselect_rs {
3153 my $attrs = $self->_resolved_attrs;
3155 my $fresh_rs = (ref $self)->new (
3156 $self->result_source
3159 # these pieces will be locked in the subquery
3160 delete $fresh_rs->{cond};
3161 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3163 return $fresh_rs->search( {}, {
3165 $attrs->{alias} => $self->as_query,
3166 -alias => $attrs->{alias},
3167 -rsrc => $self->result_source,
3169 alias => $attrs->{alias},
3173 # This code is called by search_related, and makes sure there
3174 # is clear separation between the joins before, during, and
3175 # after the relationship. This information is needed later
3176 # in order to properly resolve prefetch aliases (any alias
3177 # with a relation_chain_depth less than the depth of the
3178 # current prefetch is not considered)
3180 # The increments happen twice per join. An even number means a
3181 # relationship specified via a search_related, whereas an odd
3182 # number indicates a join/prefetch added via attributes
3184 # Also this code will wrap the current resultset (the one we
3185 # chain to) in a subselect IFF it contains limiting attributes
3186 sub _chain_relationship {
3187 my ($self, $rel) = @_;
3188 my $source = $self->result_source;
3189 my $attrs = { %{$self->{attrs}||{}} };
3191 # we need to take the prefetch the attrs into account before we
3192 # ->_resolve_join as otherwise they get lost - captainL
3193 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3195 delete @{$attrs}{qw/join prefetch collapse group_by distinct select as columns +select +as +columns/};
3197 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3200 my @force_subq_attrs = qw/offset rows group_by having/;
3203 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3205 $self->_has_resolved_attr (@force_subq_attrs)
3207 # Nuke the prefetch (if any) before the new $rs attrs
3208 # are resolved (prefetch is useless - we are wrapping
3209 # a subquery anyway).
3210 my $rs_copy = $self->search;
3211 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3212 $rs_copy->{attrs}{join},
3213 delete $rs_copy->{attrs}{prefetch},
3218 -alias => $attrs->{alias},
3219 $attrs->{alias} => $rs_copy->as_query,
3221 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3222 $seen->{-relation_chain_depth} = 0;
3224 elsif ($attrs->{from}) { #shallow copy suffices
3225 $from = [ @{$attrs->{from}} ];
3230 -alias => $attrs->{alias},
3231 $attrs->{alias} => $source->from,
3235 my $jpath = ($seen->{-relation_chain_depth})
3236 ? $from->[-1][0]{-join_path}
3239 my @requested_joins = $source->_resolve_join(
3246 push @$from, @requested_joins;
3248 $seen->{-relation_chain_depth}++;
3250 # if $self already had a join/prefetch specified on it, the requested
3251 # $rel might very well be already included. What we do in this case
3252 # is effectively a no-op (except that we bump up the chain_depth on
3253 # the join in question so we could tell it *is* the search_related)
3256 # we consider the last one thus reverse
3257 for my $j (reverse @requested_joins) {
3258 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3259 if ($rel eq $last_j) {
3260 $j->[0]{-relation_chain_depth}++;
3266 unless ($already_joined) {
3267 push @$from, $source->_resolve_join(
3275 $seen->{-relation_chain_depth}++;
3277 return {%$attrs, from => $from, seen_join => $seen};
3280 # FIXME - this needs to go live in Schema with the tree walker... or
3282 my $inflatemap_checker;
3283 $inflatemap_checker = sub {
3284 my ($rsrc, $relpaths) = @_;
3289 $_ =~ /^ ( [^\.]+ ) \. (.+) $/x
3292 push @{$rels->{$1}}, $2;
3295 for my $rel (keys %$rels) {
3296 my $rel_rsrc = try {
3297 $rsrc->related_source ($rel)
3299 $rsrc->throw_exception(sprintf(
3300 "Inflation into non-existent relationship '%s' of '%s' requested, "
3301 . "check the inflation specification (columns/as) ending in '...%s.%s'",
3305 ( sort { length($a) <=> length ($b) } @{$rels->{$rel}} )[0],
3308 $inflatemap_checker->($rel_rsrc, $rels->{$rel});
3314 sub _resolved_attrs {
3316 return $self->{_attrs} if $self->{_attrs};
3318 my $attrs = { %{ $self->{attrs} || {} } };
3319 my $source = $self->result_source;
3320 my $alias = $attrs->{alias};
3322 # default selection list
3323 $attrs->{columns} = [ $source->columns ]
3324 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3326 # merge selectors together
3327 for (qw/columns select as/) {
3328 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3329 if $attrs->{$_} or $attrs->{"+$_"};
3332 # disassemble columns
3334 if (my $cols = delete $attrs->{columns}) {
3335 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3336 if (ref $c eq 'HASH') {
3337 for my $as (sort keys %$c) {
3338 push @sel, $c->{$as};
3349 # when trying to weed off duplicates later do not go past this point -
3350 # everything added from here on is unbalanced "anyone's guess" stuff
3351 my $dedup_stop_idx = $#as;
3353 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3355 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3356 if $attrs->{select};
3358 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3359 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3361 # disqualify all $alias.col as-bits (inflate-map mandated)
3362 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3364 # de-duplicate the result (remove *identical* select/as pairs)
3365 # and also die on duplicate {as} pointing to different {select}s
3366 # not using a c-style for as the condition is prone to shrinkage
3369 while ($i <= $dedup_stop_idx) {
3370 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3375 elsif ($seen->{$as[$i]}++) {
3376 $self->throw_exception(
3377 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3385 # validate the user-supplied 'as' chain
3386 # folks get too confused by the (logical) exception message, need to
3387 # go to some lengths to clarify the text
3389 # FIXME - this needs to go live in Schema with the tree walker... or
3391 $inflatemap_checker->($source, \@as);
3393 $attrs->{select} = \@sel;
3394 $attrs->{as} = \@as;
3396 $attrs->{from} ||= [{
3398 -alias => $self->{attrs}{alias},
3399 $self->{attrs}{alias} => $source->from,
3402 if ( $attrs->{join} || $attrs->{prefetch} ) {
3404 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3405 if ref $attrs->{from} ne 'ARRAY';
3407 my $join = (delete $attrs->{join}) || {};
3409 if ( defined $attrs->{prefetch} ) {
3410 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3413 $attrs->{from} = # have to copy here to avoid corrupting the original
3415 @{ $attrs->{from} },
3416 $source->_resolve_join(
3419 { %{ $attrs->{seen_join} || {} } },
3420 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3421 ? $attrs->{from}[-1][0]{-join_path}
3428 if ( defined $attrs->{order_by} ) {
3429 $attrs->{order_by} = (
3430 ref( $attrs->{order_by} ) eq 'ARRAY'
3431 ? [ @{ $attrs->{order_by} } ]
3432 : [ $attrs->{order_by} || () ]
3436 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3437 $attrs->{group_by} = [ $attrs->{group_by} ];
3440 # generate the distinct induced group_by early, as prefetch will be carried via a
3441 # subquery (since a group_by is present)
3442 if (delete $attrs->{distinct}) {
3443 if ($attrs->{group_by}) {
3444 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3447 # distinct affects only the main selection part, not what prefetch may
3449 $attrs->{group_by} = $source->storage->_group_over_selection (
3457 # generate selections based on the prefetch helper
3459 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3460 if defined $attrs->{prefetch};
3464 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3465 if $attrs->{_dark_selector};
3467 $attrs->{collapse} = 1;
3469 # this is a separate structure (we don't look in {from} directly)
3470 # as the resolver needs to shift things off the lists to work
3471 # properly (identical-prefetches on different branches)
3473 if (ref $attrs->{from} eq 'ARRAY') {
3475 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3477 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3478 next unless $j->[0]{-alias};
3479 next unless $j->[0]{-join_path};
3480 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3482 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3485 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3486 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3490 my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map );
3492 # we need to somehow mark which columns came from prefetch
3494 my $sel_end = $#{$attrs->{select}};
3495 $attrs->{_prefetch_selector_range} = [ $sel_end + 1, $sel_end + @prefetch ];
3498 push @{ $attrs->{select} }, (map { $_->[0] } @prefetch);
3499 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
3502 if ( ! List::Util::first { $_ =~ /\./ } @{$attrs->{as}} ) {
3503 $attrs->{_single_object_inflation} = 1;
3504 $attrs->{collapse} = 0;
3507 # run through the resulting joinstructure (starting from our current slot)
3508 # and unset collapse if proven unnesessary
3510 # also while we are at it find out if the current root source has
3511 # been premultiplied by previous related_source chaining
3513 # this allows to predict whether a root object with all other relation
3514 # data set to NULL is in fact unique
3515 if ($attrs->{collapse}) {
3517 if (ref $attrs->{from} eq 'ARRAY') {
3519 if (@{$attrs->{from}} <= 1) {
3520 # no joins - no collapse
3521 $attrs->{collapse} = 0;
3524 # find where our table-spec starts
3525 my @fromlist = @{$attrs->{from}};
3527 my $t = shift @fromlist;
3530 # me vs join from-spec distinction - a ref means non-root
3531 if (ref $t eq 'ARRAY') {
3533 $is_multi ||= ! $t->{-is_single};
3535 last if ($t->{-alias} && $t->{-alias} eq $alias);
3536 $attrs->{_main_source_premultiplied} ||= $is_multi;
3539 # no non-singles remaining, nor any premultiplication - nothing to collapse
3541 ! $attrs->{_main_source_premultiplied}
3543 ! List::Util::first { ! $_->[0]{-is_single} } @fromlist
3545 $attrs->{collapse} = 0;
3551 # if we can not analyze the from - err on the side of safety
3552 $attrs->{_main_source_premultiplied} = 1;
3556 # if both page and offset are specified, produce a combined offset
3557 # even though it doesn't make much sense, this is what pre 081xx has
3559 if (my $page = delete $attrs->{page}) {
3561 ($attrs->{rows} * ($page - 1))
3563 ($attrs->{offset} || 0)
3567 return $self->{_attrs} = $attrs;
3571 my ($self, $attr) = @_;
3573 if (ref $attr eq 'HASH') {
3574 return $self->_rollout_hash($attr);
3575 } elsif (ref $attr eq 'ARRAY') {
3576 return $self->_rollout_array($attr);
3582 sub _rollout_array {
3583 my ($self, $attr) = @_;
3586 foreach my $element (@{$attr}) {
3587 if (ref $element eq 'HASH') {
3588 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3589 } elsif (ref $element eq 'ARRAY') {
3590 # XXX - should probably recurse here
3591 push( @rolled_array, @{$self->_rollout_array($element)} );
3593 push( @rolled_array, $element );
3596 return \@rolled_array;
3600 my ($self, $attr) = @_;
3603 foreach my $key (keys %{$attr}) {
3604 push( @rolled_array, { $key => $attr->{$key} } );
3606 return \@rolled_array;
3609 sub _calculate_score {
3610 my ($self, $a, $b) = @_;
3612 if (defined $a xor defined $b) {
3615 elsif (not defined $a) {
3619 if (ref $b eq 'HASH') {
3620 my ($b_key) = keys %{$b};
3621 if (ref $a eq 'HASH') {
3622 my ($a_key) = keys %{$a};
3623 if ($a_key eq $b_key) {
3624 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3629 return ($a eq $b_key) ? 1 : 0;
3632 if (ref $a eq 'HASH') {
3633 my ($a_key) = keys %{$a};
3634 return ($b eq $a_key) ? 1 : 0;
3636 return ($b eq $a) ? 1 : 0;
3641 sub _merge_joinpref_attr {
3642 my ($self, $orig, $import) = @_;
3644 return $import unless defined($orig);
3645 return $orig unless defined($import);
3647 $orig = $self->_rollout_attr($orig);
3648 $import = $self->_rollout_attr($import);
3651 foreach my $import_element ( @{$import} ) {
3652 # find best candidate from $orig to merge $b_element into
3653 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3654 foreach my $orig_element ( @{$orig} ) {
3655 my $score = $self->_calculate_score( $orig_element, $import_element );
3656 if ($score > $best_candidate->{score}) {
3657 $best_candidate->{position} = $position;
3658 $best_candidate->{score} = $score;
3662 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3663 $import_key = '' if not defined $import_key;
3665 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3666 push( @{$orig}, $import_element );
3668 my $orig_best = $orig->[$best_candidate->{position}];
3669 # merge orig_best and b_element together and replace original with merged
3670 if (ref $orig_best ne 'HASH') {
3671 $orig->[$best_candidate->{position}] = $import_element;
3672 } elsif (ref $import_element eq 'HASH') {
3673 my ($key) = keys %{$orig_best};
3674 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3677 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3680 return @$orig ? $orig : ();
3688 require Hash::Merge;
3689 my $hm = Hash::Merge->new;
3691 $hm->specify_behavior({
3694 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3696 if ($defl xor $defr) {
3697 return [ $defl ? $_[0] : $_[1] ];
3702 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3706 return [$_[0], $_[1]];
3710 return $_[1] if !defined $_[0];
3711 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3712 return [$_[0], @{$_[1]}]
3715 return [] if !defined $_[0] and !keys %{$_[1]};
3716 return [ $_[1] ] if !defined $_[0];
3717 return [ $_[0] ] if !keys %{$_[1]};
3718 return [$_[0], $_[1]]
3723 return $_[0] if !defined $_[1];
3724 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3725 return [@{$_[0]}, $_[1]]
3728 my @ret = @{$_[0]} or return $_[1];
3729 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3730 my %idx = map { $_ => 1 } @ret;
3731 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3735 return [ $_[1] ] if ! @{$_[0]};
3736 return $_[0] if !keys %{$_[1]};
3737 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3738 return [ @{$_[0]}, $_[1] ];
3743 return [] if !keys %{$_[0]} and !defined $_[1];
3744 return [ $_[0] ] if !defined $_[1];
3745 return [ $_[1] ] if !keys %{$_[0]};
3746 return [$_[0], $_[1]]
3749 return [] if !keys %{$_[0]} and !@{$_[1]};
3750 return [ $_[0] ] if !@{$_[1]};
3751 return $_[1] if !keys %{$_[0]};
3752 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3753 return [ $_[0], @{$_[1]} ];
3756 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3757 return [ $_[0] ] if !keys %{$_[1]};
3758 return [ $_[1] ] if !keys %{$_[0]};
3759 return [ $_[0] ] if $_[0] eq $_[1];
3760 return [ $_[0], $_[1] ];
3763 } => 'DBIC_RS_ATTR_MERGER');
3767 return $hm->merge ($_[1], $_[2]);
3771 sub STORABLE_freeze {
3772 my ($self, $cloning) = @_;
3773 my $to_serialize = { %$self };
3775 # A cursor in progress can't be serialized (and would make little sense anyway)
3776 # the parser can be regenerated (and can't be serialized)
3777 delete @{$to_serialize}{qw/cursor _row_parser/};
3779 # nor is it sensical to store a not-yet-fired-count pager
3780 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3781 delete $to_serialize->{pager};
3784 Storable::nfreeze($to_serialize);
3787 # need this hook for symmetry
3789 my ($self, $cloning, $serialized) = @_;
3791 %$self = %{ Storable::thaw($serialized) };
3797 =head2 throw_exception
3799 See L<DBIx::Class::Schema/throw_exception> for details.
3803 sub throw_exception {
3806 if (ref $self and my $rsrc = $self->result_source) {
3807 $rsrc->throw_exception(@_)
3810 DBIx::Class::Exception->throw(@_);
3814 # XXX: FIXME: Attributes docs need clearing up
3818 Attributes are used to refine a ResultSet in various ways when
3819 searching for data. They can be passed to any method which takes an
3820 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3823 Default attributes can be set on the result class using
3824 L<DBIx::Class::ResultSource/resultset_attributes>. (Please read
3825 the CAVEATS on that feature before using it!)
3827 These are in no particular order:
3833 =item Value: ( $order_by | \@order_by | \%order_by )
3837 Which column(s) to order the results by.
3839 [The full list of suitable values is documented in
3840 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3843 If a single column name, or an arrayref of names is supplied, the
3844 argument is passed through directly to SQL. The hashref syntax allows
3845 for connection-agnostic specification of ordering direction:
3847 For descending order:
3849 order_by => { -desc => [qw/col1 col2 col3/] }
3851 For explicit ascending order:
3853 order_by => { -asc => 'col' }
3855 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3856 supported, although you are strongly encouraged to use the hashref
3857 syntax as outlined above.
3863 =item Value: \@columns
3867 Shortcut to request a particular set of columns to be retrieved. Each
3868 column spec may be a string (a table column name), or a hash (in which
3869 case the key is the C<as> value, and the value is used as the C<select>
3870 expression). Adds C<me.> onto the start of any column without a C<.> in
3871 it and sets C<select> from that, then auto-populates C<as> from
3872 C<select> as normal. (You may also use the C<cols> attribute, as in
3873 earlier versions of DBIC.)
3875 Essentially C<columns> does the same as L</select> and L</as>.
3877 columns => [ 'foo', { bar => 'baz' } ]
3881 select => [qw/foo baz/],
3888 =item Value: \@columns
3892 Indicates additional columns to be selected from storage. Works the same
3893 as L</columns> but adds columns to the selection. (You may also use the
3894 C<include_columns> attribute, as in earlier versions of DBIC). For
3897 $schema->resultset('CD')->search(undef, {
3898 '+columns' => ['artist.name'],
3902 would return all CDs and include a 'name' column to the information
3903 passed to object inflation. Note that the 'artist' is the name of the
3904 column (or relationship) accessor, and 'name' is the name of the column
3905 accessor in the related table.
3907 B<NOTE:> You need to explicitly quote '+columns' when defining the attribute.
3908 Not doing so causes Perl to incorrectly interpret +columns as a bareword with a
3909 unary plus operator before it.
3911 =head2 include_columns
3915 =item Value: \@columns
3919 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3925 =item Value: \@select_columns
3929 Indicates which columns should be selected from the storage. You can use
3930 column names, or in the case of RDBMS back ends, function or stored procedure
3933 $rs = $schema->resultset('Employee')->search(undef, {
3936 { count => 'employeeid' },
3937 { max => { length => 'name' }, -as => 'longest_name' }
3942 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
3944 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
3945 use L</select>, to instruct DBIx::Class how to store the result of the column.
3946 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
3947 identifier aliasing. You can however alias a function, so you can use it in
3948 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
3949 attribute> supplied as shown in the example above.
3951 B<NOTE:> You need to explicitly quote '+select'/'+as' when defining the attributes.
3952 Not doing so causes Perl to incorrectly interpret them as a bareword with a
3953 unary plus operator before it.
3959 Indicates additional columns to be selected from storage. Works the same as
3960 L</select> but adds columns to the default selection, instead of specifying
3969 Indicates additional column names for those added via L</+select>. See L</as>.
3977 =item Value: \@inflation_names
3981 Indicates column names for object inflation. That is L</as> indicates the
3982 slot name in which the column value will be stored within the
3983 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
3984 identifier by the C<get_column> method (or via the object accessor B<if one
3985 with the same name already exists>) as shown below. The L</as> attribute has
3986 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
3988 $rs = $schema->resultset('Employee')->search(undef, {
3991 { count => 'employeeid' },
3992 { max => { length => 'name' }, -as => 'longest_name' }
4001 If the object against which the search is performed already has an accessor
4002 matching a column name specified in C<as>, the value can be retrieved using
4003 the accessor as normal:
4005 my $name = $employee->name();
4007 If on the other hand an accessor does not exist in the object, you need to
4008 use C<get_column> instead:
4010 my $employee_count = $employee->get_column('employee_count');
4012 You can create your own accessors if required - see
4013 L<DBIx::Class::Manual::Cookbook> for details.
4019 =item Value: ($rel_name | \@rel_names | \%rel_names)
4023 Contains a list of relationships that should be joined for this query. For
4026 # Get CDs by Nine Inch Nails
4027 my $rs = $schema->resultset('CD')->search(
4028 { 'artist.name' => 'Nine Inch Nails' },
4029 { join => 'artist' }
4032 Can also contain a hash reference to refer to the other relation's relations.
4035 package MyApp::Schema::Track;
4036 use base qw/DBIx::Class/;
4037 __PACKAGE__->table('track');
4038 __PACKAGE__->add_columns(qw/trackid cd position title/);
4039 __PACKAGE__->set_primary_key('trackid');
4040 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
4043 # In your application
4044 my $rs = $schema->resultset('Artist')->search(
4045 { 'track.title' => 'Teardrop' },
4047 join => { cd => 'track' },
4048 order_by => 'artist.name',
4052 You need to use the relationship (not the table) name in conditions,
4053 because they are aliased as such. The current table is aliased as "me", so
4054 you need to use me.column_name in order to avoid ambiguity. For example:
4056 # Get CDs from 1984 with a 'Foo' track
4057 my $rs = $schema->resultset('CD')->search(
4060 'tracks.name' => 'Foo'
4062 { join => 'tracks' }
4065 If the same join is supplied twice, it will be aliased to <rel>_2 (and
4066 similarly for a third time). For e.g.
4068 my $rs = $schema->resultset('Artist')->search({
4069 'cds.title' => 'Down to Earth',
4070 'cds_2.title' => 'Popular',
4072 join => [ qw/cds cds/ ],
4075 will return a set of all artists that have both a cd with title 'Down
4076 to Earth' and a cd with title 'Popular'.
4078 If you want to fetch related objects from other tables as well, see C<prefetch>
4081 NOTE: An internal join-chain pruner will discard certain joins while
4082 constructing the actual SQL query, as long as the joins in question do not
4083 affect the retrieved result. This for example includes 1:1 left joins
4084 that are not part of the restriction specification (WHERE/HAVING) nor are
4085 a part of the query selection.
4087 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4093 =item Value: ($rel_name | \@rel_names | \%rel_names)
4097 Contains one or more relationships that should be fetched along with
4098 the main query (when they are accessed afterwards the data will
4099 already be available, without extra queries to the database). This is
4100 useful for when you know you will need the related objects, because it
4101 saves at least one query:
4103 my $rs = $schema->resultset('Tag')->search(
4112 The initial search results in SQL like the following:
4114 SELECT tag.*, cd.*, artist.* FROM tag
4115 JOIN cd ON tag.cd = cd.cdid
4116 JOIN artist ON cd.artist = artist.artistid
4118 L<DBIx::Class> has no need to go back to the database when we access the
4119 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4122 Simple prefetches will be joined automatically, so there is no need
4123 for a C<join> attribute in the above search.
4125 L</prefetch> can be used with the any of the relationship types and
4126 multiple prefetches can be specified together. Below is a more complex
4127 example that prefetches a CD's artist, its liner notes (if present),
4128 the cover image, the tracks on that cd, and the guests on those
4132 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4133 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4134 My::Schema::CD->has_one( cover_image => 'My::Schema::Artwork' );
4135 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4137 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4139 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4142 my $rs = $schema->resultset('CD')->search(
4146 { artist => 'record_label'}, # belongs_to => belongs_to
4147 'liner_note', # might_have
4148 'cover_image', # has_one
4149 { tracks => 'guests' }, # has_many => has_many
4154 This will produce SQL like the following:
4156 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4160 ON artist.artistid = me.artistid
4161 JOIN record_label record_label
4162 ON record_label.labelid = artist.labelid
4163 LEFT JOIN track tracks
4164 ON tracks.cdid = me.cdid
4165 LEFT JOIN guest guests
4166 ON guests.trackid = track.trackid
4167 LEFT JOIN liner_notes liner_note
4168 ON liner_note.cdid = me.cdid
4169 JOIN cd_artwork cover_image
4170 ON cover_image.cdid = me.cdid
4173 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4174 C<tracks>, and C<guests> of the CD will all be available through the
4175 relationship accessors without the need for additional queries to the
4178 However, there is one caveat to be observed: it can be dangerous to
4179 prefetch more than one L<has_many|DBIx::Class::Relationship/has_many>
4180 relationship on a given level. e.g.:
4182 my $rs = $schema->resultset('CD')->search(
4186 'tracks', # has_many
4187 { cd_to_producer => 'producer' }, # has_many => belongs_to (i.e. m2m)
4192 The collapser currently can't identify duplicate tuples for multiple
4193 L<has_many|DBIx::Class::Relationship/has_many> relationships and as a
4194 result the second L<has_many|DBIx::Class::Relationship/has_many>
4195 relation could contain redundant objects.
4197 =head3 Using L</prefetch> with L</join>
4199 L</prefetch> implies a L</join> with the equivalent argument, and is
4200 properly merged with any existing L</join> specification. So the
4203 my $rs = $schema->resultset('CD')->search(
4204 {'record_label.name' => 'Music Product Ltd.'},
4206 join => {artist => 'record_label'},
4207 prefetch => 'artist',
4211 ... will work, searching on the record label's name, but only
4212 prefetching the C<artist>.
4214 =head3 Using L</prefetch> with L</select> / L</+select> / L</as> / L</+as>
4216 L</prefetch> implies a L</+select>/L</+as> with the fields of the
4217 prefetched relations. So given:
4219 my $rs = $schema->resultset('CD')->search(
4222 select => ['cd.title'],
4224 prefetch => 'artist',
4228 The L</select> becomes: C<'cd.title', 'artist.*'> and the L</as>
4229 becomes: C<'cd_title', 'artist.*'>.
4233 Prefetch does a lot of deep magic. As such, it may not behave exactly
4234 as you might expect.
4240 Prefetch uses the L</cache> to populate the prefetched relationships. This
4241 may or may not be what you want.
4245 If you specify a condition on a prefetched relationship, ONLY those
4246 rows that match the prefetched condition will be fetched into that relationship.
4247 This means that adding prefetch to a search() B<may alter> what is returned by
4248 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4250 my $artist_rs = $schema->resultset('Artist')->search({
4256 my $count = $artist_rs->first->cds->count;
4258 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4260 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4262 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4264 that cmp_ok() may or may not pass depending on the datasets involved. This
4265 behavior may or may not survive the 0.09 transition.
4273 =item Value: $source_alias
4277 Sets the source alias for the query. Normally, this defaults to C<me>, but
4278 nested search queries (sub-SELECTs) might need specific aliases set to
4279 reference inner queries. For example:
4282 ->related_resultset('CDs')
4283 ->related_resultset('Tracks')
4285 'track.id' => { -ident => 'none_search.id' },
4289 my $ids = $self->search({
4292 alias => 'none_search',
4293 group_by => 'none_search.id',
4294 })->get_column('id')->as_query;
4296 $self->search({ id => { -in => $ids } })
4298 This attribute is directly tied to L</current_source_alias>.
4308 Makes the resultset paged and specifies the page to retrieve. Effectively
4309 identical to creating a non-pages resultset and then calling ->page($page)
4312 If L</rows> attribute is not specified it defaults to 10 rows per page.
4314 When you have a paged resultset, L</count> will only return the number
4315 of rows in the page. To get the total, use the L</pager> and call
4316 C<total_entries> on it.
4326 Specifies the maximum number of rows for direct retrieval or the number of
4327 rows per page if the page attribute or method is used.
4333 =item Value: $offset
4337 Specifies the (zero-based) row number for the first row to be returned, or the
4338 of the first row of the first page if paging is used.
4340 =head2 software_limit
4344 =item Value: (0 | 1)
4348 When combined with L</rows> and/or L</offset> the generated SQL will not
4349 include any limit dialect stanzas. Instead the entire result will be selected
4350 as if no limits were specified, and DBIC will perform the limit locally, by
4351 artificially advancing and finishing the resulting L</cursor>.
4353 This is the recommended way of performing resultset limiting when no sane RDBMS
4354 implementation is available (e.g.
4355 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4356 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4362 =item Value: \@columns
4366 A arrayref of columns to group by. Can include columns of joined tables.
4368 group_by => [qw/ column1 column2 ... /]
4374 =item Value: $condition
4378 HAVING is a select statement attribute that is applied between GROUP BY and
4379 ORDER BY. It is applied to the after the grouping calculations have been
4382 having => { 'count_employee' => { '>=', 100 } }
4384 or with an in-place function in which case literal SQL is required:
4386 having => \[ 'count(employee) >= ?', [ count => 100 ] ]
4392 =item Value: (0 | 1)
4396 Set to 1 to group by all columns. If the resultset already has a group_by
4397 attribute, this setting is ignored and an appropriate warning is issued.
4403 Adds to the WHERE clause.
4405 # only return rows WHERE deleted IS NULL for all searches
4406 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4408 Can be overridden by passing C<< { where => undef } >> as an attribute
4411 For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
4417 Set to 1 to cache search results. This prevents extra SQL queries if you
4418 revisit rows in your ResultSet:
4420 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4422 while( my $artist = $resultset->next ) {
4426 $rs->first; # without cache, this would issue a query
4428 By default, searches are not cached.
4430 For more examples of using these attributes, see
4431 L<DBIx::Class::Manual::Cookbook>.
4437 =item Value: ( 'update' | 'shared' | \$scalar )
4441 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4442 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4445 =head1 DBIC BIND VALUES
4447 Because DBIC may need more information to bind values than just the column name
4448 and value itself, it uses a special format for both passing and receiving bind
4449 values. Each bind value should be composed of an arrayref of
4450 C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
4456 If present (in any form), this is what is being passed directly to bind_param.
4457 Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
4458 a single numerical type, while DBD::Pg takes a hashref if bind options.)
4460 If this is specified, all other bind options described below are ignored.
4464 If present, this is used to infer the actual bind attribute by passing to
4465 C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
4466 "data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
4468 Note that the data type is somewhat freeform (hence the sqlt_ prefix);
4469 currently drivers are expected to "Do the Right Thing" when given a common
4470 datatype name. (Not ideal, but that's what we got at this point.)
4474 Currently used to correctly allocate buffers for bind_param_inout().
4475 Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
4476 or to a sensible value based on the "data_type".
4480 Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
4481 explicitly specified they are never overriden). Also used by some weird DBDs,
4482 where the column name should be available at bind_param time (e.g. Oracle).
4486 For backwards compatibility and convenience, the following shortcuts are
4489 [ $name => $val ] === [ { dbic_colname => $name }, $val ]
4490 [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
4491 [ undef, $val ] === [ {}, $val ]
4493 =head1 AUTHOR AND CONTRIBUTORS
4495 See L<AUTHOR|DBIx::Class/AUTHOR> and L<CONTRIBUTORS|DBIx::Class/CONTRIBUTORS> in DBIx::Class
4499 You may distribute this code under the same terms as Perl itself.