1 package DBIx::Class::ResultSet;
6 use base 'DBIx::Class';
9 use DBIx::Class::ResultSetColumn;
10 use DBIx::Class::ResultClass::HashRefInflator;
11 use Scalar::Util qw( blessed reftype );
12 use DBIx::Class::_Util qw(
13 dbic_internal_try dump_value
14 fail_on_internal_wantarray fail_on_internal_call UNRESOLVABLE_CONDITION
16 use DBIx::Class::SQLMaker::Util qw( normalize_sqla_condition extract_equality_conditions );
20 # De-duplication in _merge_attr() is disabled, but left in for reference
21 # (the merger is used for other things that ought not to be de-duped)
22 *__HM_DEDUP = sub () { 0 };
32 # this is real - CDBICompat overrides it with insanity
33 # yes, prototype won't matter, but that's for now ;)
36 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class result_source/);
40 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
44 my $users_rs = $schema->resultset('User');
45 while( $user = $users_rs->next) {
46 print $user->username;
49 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
50 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
54 A ResultSet is an object which stores a set of conditions representing
55 a query. It is the backbone of DBIx::Class (i.e. the really
56 important/useful bit).
58 No SQL is executed on the database when a ResultSet is created, it
59 just stores all the conditions needed to create the query.
61 A basic ResultSet representing the data of an entire table is returned
62 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
63 L<Source|DBIx::Class::Manual::Glossary/ResultSource> name.
65 my $users_rs = $schema->resultset('User');
67 A new ResultSet is returned from calling L</search> on an existing
68 ResultSet. The new one will contain all the conditions of the
69 original, plus any new conditions added in the C<search> call.
71 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
72 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
75 The query that the ResultSet represents is B<only> executed against
76 the database when these methods are called:
77 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
79 If a resultset is used in a numeric context it returns the L</count>.
80 However, if it is used in a boolean context it is B<always> true. So if
81 you want to check if a resultset has any results, you must use C<if $rs
86 =head2 Chaining resultsets
88 Let's say you've got a query that needs to be run to return some data
89 to the user. But, you have an authorization system in place that
90 prevents certain users from seeing certain information. So, you want
91 to construct the basic query in one method, but add constraints to it in
96 my $request = $self->get_request; # Get a request object somehow.
97 my $schema = $self->result_source->schema;
99 my $cd_rs = $schema->resultset('CD')->search({
100 title => $request->param('title'),
101 year => $request->param('year'),
104 $cd_rs = $self->apply_security_policy( $cd_rs );
106 return $cd_rs->all();
109 sub apply_security_policy {
118 =head3 Resolving conditions and attributes
120 When a resultset is chained from another resultset (e.g.:
121 C<< my $new_rs = $old_rs->search(\%extra_cond, \%attrs) >>), conditions
122 and attributes with the same keys need resolving.
124 If any of L</columns>, L</select>, L</as> are present, they reset the
125 original selection, and start the selection "clean".
127 The L</join>, L</prefetch>, L</+columns>, L</+select>, L</+as> attributes
128 are merged into the existing ones from the original resultset.
130 The L</where> and L</having> attributes, and any search conditions, are
131 merged with an SQL C<AND> to the existing condition from the original
134 All other attributes are overridden by any new ones supplied in the
137 =head2 Multiple queries
139 Since a resultset just defines a query, you can do all sorts of
140 things with it with the same object.
142 # Don't hit the DB yet.
143 my $cd_rs = $schema->resultset('CD')->search({
144 title => 'something',
148 # Each of these hits the DB individually.
149 my $count = $cd_rs->count;
150 my $most_recent = $cd_rs->get_column('date_released')->max();
151 my @records = $cd_rs->all;
153 And it's not just limited to SELECT statements.
159 $cd_rs->create({ artist => 'Fred' });
161 Which is the same as:
163 $schema->resultset('CD')->create({
164 title => 'something',
169 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
171 =head2 Custom ResultSet classes
173 To add methods to your resultsets, you can subclass L<DBIx::Class::ResultSet>, similar to:
175 package MyApp::Schema::ResultSet::User;
180 use base 'DBIx::Class::ResultSet';
184 $self->search({ $self->current_source_alias . '.active' => 1 });
189 $self->search({ $self->current_source_alias . '.verified' => 0 });
192 sub created_n_days_ago {
193 my ($self, $days_ago) = @_;
195 $self->current_source_alias . '.create_date' => {
197 $self->result_source->schema->storage->datetime_parser->format_datetime(
198 DateTime->now( time_zone => 'UTC' )->subtract( days => $days_ago )
203 sub users_to_warn { shift->active->unverified->created_n_days_ago(7) }
207 See L<DBIx::Class::Schema/load_namespaces> on how DBIC can discover and
208 automatically attach L<Result|DBIx::Class::Manual::ResultClass>-specific
209 L<ResulSet|DBIx::Class::ResultSet> classes.
211 =head3 ResultSet subclassing with Moose and similar constructor-providers
213 Using L<Moose> or L<Moo> in your ResultSet classes is usually overkill, but
214 you may find it useful if your ResultSets contain a lot of business logic
215 (e.g. C<has xml_parser>, C<has json>, etc) or if you just prefer to organize
218 In order to write custom ResultSet classes with L<Moo> you need to use the
219 following template. The L<BUILDARGS|Moo/BUILDARGS> is necessary due to the
220 unusual signature of the L<constructor provided by DBIC
221 |DBIx::Class::ResultSet/new> C<< ->new($source, \%args) >>.
224 extends 'DBIx::Class::ResultSet';
225 sub BUILDARGS { $_[2] } # ::RS::new() expects my ($class, $rsrc, $args) = @_
231 If you want to build your custom ResultSet classes with L<Moose>, you need
232 a similar, though a little more elaborate template in order to interface the
233 inlining of the L<Moose>-provided
234 L<object constructor|Moose::Manual::Construction/WHERE'S THE CONSTRUCTOR?>,
237 package MyApp::Schema::ResultSet::User;
240 use MooseX::NonMoose;
241 extends 'DBIx::Class::ResultSet';
243 sub BUILDARGS { $_[2] } # ::RS::new() expects my ($class, $rsrc, $args) = @_
247 __PACKAGE__->meta->make_immutable;
251 The L<MooseX::NonMoose> is necessary so that the L<Moose> constructor does not
252 entirely overwrite the DBIC one (in contrast L<Moo> does this automatically).
253 Alternatively, you can skip L<MooseX::NonMoose> and get by with just L<Moose>
256 __PACKAGE__->meta->make_immutable(inline_constructor => 0);
264 =item Arguments: L<$source|DBIx::Class::ResultSource>, L<\%attrs?|/ATTRIBUTES>
266 =item Return Value: L<$resultset|/search>
270 The resultset constructor. Takes a source object (usually a
271 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
272 L</ATTRIBUTES> below). Does not perform any queries -- these are
273 executed as needed by the other methods.
275 Generally you never construct a resultset manually. Instead you get one
277 C<< $schema->L<resultset|DBIx::Class::Schema/resultset>('$source_name') >>
278 or C<< $another_resultset->L<search|/search>(...) >> (the later called in
281 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
287 If called on an object, proxies to L</new_result> instead, so
289 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
291 will return a CD object, not a ResultSet, and is equivalent to:
293 my $cd = $schema->resultset('CD')->new_result({ title => 'Spoon' });
295 Please also keep in mind that many internals call L</new_result> directly,
296 so overloading this method with the idea of intercepting new result object
297 creation B<will not work>. See also warning pertaining to L</create>.
307 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
308 return $class->new_result(@_);
311 my ($source, $attrs) = @_;
312 $source = $source->resolve
313 if $source->isa('DBIx::Class::ResultSourceHandle');
315 $attrs = { %{$attrs||{}} };
316 delete @{$attrs}{qw(_last_sqlmaker_alias_map _simple_passthrough_construction)};
318 if ($attrs->{page}) {
319 $attrs->{rows} ||= 10;
322 $attrs->{alias} ||= 'me';
325 result_source => $source,
326 cond => $attrs->{where},
331 # if there is a dark selector, this means we are already in a
332 # chain and the cleanup/sanification was taken care of by
334 $self->_normalize_selection($attrs)
335 unless $attrs->{_dark_selector};
338 $attrs->{result_class} || $source->result_class
348 =item Arguments: L<$cond|DBIx::Class::SQLMaker> | undef, L<\%attrs?|/ATTRIBUTES>
350 =item Return Value: $resultset (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
354 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
355 my $new_rs = $cd_rs->search({ year => 2005 });
357 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
358 # year = 2005 OR year = 2004
360 In list context, C<< ->all() >> is called implicitly on the resultset, thus
361 returning a list of L<result|DBIx::Class::Manual::ResultClass> objects instead.
362 To avoid that, use L</search_rs>.
364 If you need to pass in additional attributes but no additional condition,
365 call it as C<search(undef, \%attrs)>.
367 # "SELECT name, artistid FROM $artist_table"
368 my @all_artists = $schema->resultset('Artist')->search(undef, {
369 columns => [qw/name artistid/],
372 For a list of attributes that can be passed to C<search>, see
373 L</ATTRIBUTES>. For more examples of using this function, see
374 L<Searching|DBIx::Class::Manual::Cookbook/SEARCHING>. For a complete
375 documentation for the first argument, see L<SQL::Abstract/"WHERE CLAUSES">
376 and its extension L<DBIx::Class::SQLMaker>.
378 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
382 Note that L</search> does not process/deflate any of the values passed in the
383 L<SQL::Abstract>-compatible search condition structure. This is unlike other
384 condition-bound methods L</new_result>, L</create> and L</find>. The user must ensure
385 manually that any value passed to this method will stringify to something the
386 RDBMS knows how to deal with. A notable example is the handling of L<DateTime>
387 objects, for more info see:
388 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
394 my $rs = $self->search_rs( @_ );
397 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_WANTARRAY and my $sog = fail_on_internal_wantarray;
400 elsif (defined wantarray) {
404 # we can be called by a relationship helper, which in
405 # turn may be called in void context due to some braindead
406 # overload or whatever else the user decided to be clever
407 # at this particular day. Thus limit the exception to
408 # external code calls only
409 $self->throw_exception ('->search is *not* a mutator, calling it in void context makes no sense')
410 if (caller)[0] !~ /^\QDBIx::Class::/;
420 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
422 =item Return Value: L<$resultset|/search>
426 This method does the same exact thing as search() except it will
427 always return a resultset, even in list context.
434 my $rsrc = $self->result_source;
435 my ($call_cond, $call_attrs);
437 # Special-case handling for (undef, undef) or (undef)
438 # Note that (foo => undef) is valid deprecated syntax
439 @_ = () if not scalar grep { defined $_ } @_;
445 # fish out attrs in the ($condref, $attr) case
446 elsif (@_ == 2 and ( ! defined $_[0] or length ref $_[0] ) ) {
447 ($call_cond, $call_attrs) = @_;
450 $self->throw_exception('Odd number of arguments to search')
454 carp_unique 'search( %condition ) is deprecated, use search( \%condition ) instead'
455 unless $rsrc->result_class->isa('DBIx::Class::CDBICompat');
457 for my $i (0 .. $#_) {
459 $self->throw_exception ('All keys in condition key/value pairs must be plain scalars')
460 if (! defined $_[$i] or length ref $_[$i] );
466 # see if we can keep the cache (no $rs changes)
468 my %safe = (alias => 1, cache => 1);
469 if ( ! grep { !$safe{$_} } keys %$call_attrs and (
472 ref $call_cond eq 'HASH' && ! keys %$call_cond
474 ref $call_cond eq 'ARRAY' && ! @$call_cond
476 $cache = $self->get_cache;
479 my $old_attrs = { %{$self->{attrs}} };
480 my ($old_having, $old_where) = delete @{$old_attrs}{qw(having where)};
482 my $new_attrs = { %$old_attrs };
484 # take care of call attrs (only if anything is changing)
485 if ($call_attrs and keys %$call_attrs) {
487 # copy for _normalize_selection
488 $call_attrs = { %$call_attrs };
490 my @selector_attrs = qw/select as columns cols +select +as +columns include_columns/;
492 # reset the current selector list if new selectors are supplied
493 delete @{$old_attrs}{(@selector_attrs, '_dark_selector')}
494 if grep { exists $call_attrs->{$_} } qw(columns cols select as);
496 # Normalize the new selector list (operates on the passed-in attr structure)
497 # Need to do it on every chain instead of only once on _resolved_attrs, in
498 # order to allow detection of empty vs partial 'as'
499 $call_attrs->{_dark_selector} = $old_attrs->{_dark_selector}
500 if $old_attrs->{_dark_selector};
501 $self->_normalize_selection ($call_attrs);
503 # start with blind overwriting merge, exclude selector attrs
504 $new_attrs = { %{$old_attrs}, %{$call_attrs} };
505 delete @{$new_attrs}{@selector_attrs};
507 for (@selector_attrs) {
508 $new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
509 if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
512 # older deprecated name, use only if {columns} is not there
513 if (my $c = delete $new_attrs->{cols}) {
514 carp_unique( "Resultset attribute 'cols' is deprecated, use 'columns' instead" );
515 if ($new_attrs->{columns}) {
516 carp "Resultset specifies both the 'columns' and the legacy 'cols' attributes - ignoring 'cols'";
519 $new_attrs->{columns} = $c;
524 # join/prefetch use their own crazy merging heuristics
525 foreach my $key (qw/join prefetch/) {
526 $new_attrs->{$key} = $self->_merge_joinpref_attr($old_attrs->{$key}, $call_attrs->{$key})
527 if exists $call_attrs->{$key};
530 # stack binds together
531 $new_attrs->{bind} = [ @{ $old_attrs->{bind} || [] }, @{ $call_attrs->{bind} || [] } ];
535 for ($old_where, $call_cond) {
537 $new_attrs->{where} = $self->_stack_cond (
538 $_, $new_attrs->{where}
543 if (defined $old_having) {
544 $new_attrs->{having} = $self->_stack_cond (
545 $old_having, $new_attrs->{having}
549 my $rs = (ref $self)->new($rsrc, $new_attrs);
551 $rs->set_cache($cache) if ($cache);
556 sub _normalize_selection {
557 my ($self, $attrs) = @_;
560 if ( exists $attrs->{include_columns} ) {
561 carp_unique( "Resultset attribute 'include_columns' is deprecated, use '+columns' instead" );
562 $attrs->{'+columns'} = $self->_merge_attr(
563 $attrs->{'+columns'}, delete $attrs->{include_columns}
567 # columns are always placed first, however
569 # Keep the X vs +X separation until _resolved_attrs time - this allows to
570 # delay the decision on whether to use a default select list ($rsrc->columns)
571 # allowing stuff like the remove_columns helper to work
573 # select/as +select/+as pairs need special handling - the amount of select/as
574 # elements in each pair does *not* have to be equal (think multicolumn
575 # selectors like distinct(foo, bar) ). If the selector is bare (no 'as'
576 # supplied at all) - try to infer the alias, either from the -as parameter
577 # of the selector spec, or use the parameter whole if it looks like a column
578 # name (ugly legacy heuristic). If all fails - leave the selector bare (which
579 # is ok as well), but make sure no more additions to the 'as' chain take place
580 for my $pref ('', '+') {
582 my ($sel, $as) = map {
583 my $key = "${pref}${_}";
585 my $val = [ ref $attrs->{$key} eq 'ARRAY'
587 : $attrs->{$key} || ()
589 delete $attrs->{$key};
593 if (! @$as and ! @$sel ) {
596 elsif (@$as and ! @$sel) {
597 $self->throw_exception(
598 "Unable to handle ${pref}as specification (@$as) without a corresponding ${pref}select"
602 # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
603 # if any @$as has been supplied we assume the user knows what (s)he is doing
604 # and blindly keep stacking up pieces
605 unless ($attrs->{_dark_selector}) {
608 if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
609 push @$as, $_->{-as};
611 # assume any plain no-space, no-parenthesis string to be a column spec
612 # FIXME - this is retarded but is necessary to support shit like 'count(foo)'
613 elsif ( ! ref $_ and $_ =~ /^ [^\s\(\)]+ $/x) {
616 # if all else fails - raise a flag that no more aliasing will be allowed
618 $attrs->{_dark_selector} = {
621 local $Data::Dumper::Indent = 0;
630 elsif (@$as < @$sel) {
631 $self->throw_exception(
632 "Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
635 elsif ($pref and $attrs->{_dark_selector}) {
636 $self->throw_exception(
637 "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
643 $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
644 $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
649 my ($self, $left, $right) = @_;
652 (ref $_ eq 'ARRAY' and !@$_)
654 (ref $_ eq 'HASH' and ! keys %$_)
655 ) and $_ = undef for ($left, $right);
658 # either one of the two undef
659 ( (defined $left) xor (defined $right) ) ? ( defined $left ? $left : $right )
662 : ( ! defined $left ) ? undef
664 : { -and => [$left, $right] }
668 =head2 search_literal
670 B<CAVEAT>: C<search_literal> is provided for Class::DBI compatibility and
671 should only be used in that context. C<search_literal> is a convenience
672 method. It is equivalent to calling C<< $schema->search(\[]) >>, but if you
673 want to ensure columns are bound correctly, use L</search>.
675 See L<DBIx::Class::Manual::Cookbook/SEARCHING> and
676 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
677 require C<search_literal>.
681 =item Arguments: $sql_fragment, @standalone_bind_values
683 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
687 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
688 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
690 Pass a literal chunk of SQL to be added to the conditional part of the
693 Example of how to use C<search> instead of C<search_literal>
695 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
696 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
701 my ($self, $sql, @bind) = @_;
703 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
706 return $self->search(\[ $sql, map [ {} => $_ ], @bind ], ($attr || () ));
713 =item Arguments: \%columns_values | @pk_values, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
715 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
719 Finds and returns a single row based on supplied criteria. Takes either a
720 hashref with the same format as L</create> (including inference of foreign
721 keys from related objects), or a list of primary key values in the same
722 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
723 declaration on the L</result_source>.
725 In either case an attempt is made to combine conditions already existing on
726 the resultset with the condition passed to this method.
728 To aid with preparing the correct query for the storage you may supply the
729 C<key> attribute, which is the name of a
730 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
731 unique constraint corresponding to the
732 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
733 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
734 to construct a query that satisfies the named unique constraint fully (
735 non-NULL values for each column member of the constraint) an exception is
738 If no C<key> is specified, the search is carried over all unique constraints
739 which are fully defined by the available condition.
741 If no such constraint is found, C<find> currently defaults to a simple
742 C<< search->(\%column_values) >> which may or may not do what you expect.
743 Note that this fallback behavior may be deprecated in further versions. If
744 you need to search with arbitrary conditions - use L</search>. If the query
745 resulting from this fallback produces more than one row, a warning to the
746 effect is issued, though only the first row is constructed and returned as
749 In addition to C<key>, L</find> recognizes and applies standard
750 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
752 Note that if you have extra concerns about the correctness of the resulting
753 query you need to specify the C<key> attribute and supply the entire condition
754 as an argument to find (since it is not always possible to perform the
755 combination of the resultset condition with the supplied one, especially if
756 the resultset condition contains literal sql).
758 For example, to find a row by its primary key:
760 my $cd = $schema->resultset('CD')->find(5);
762 You can also find a row by a specific unique constraint:
764 my $cd = $schema->resultset('CD')->find(
766 artist => 'Massive Attack',
767 title => 'Mezzanine',
769 { key => 'cd_artist_title' }
772 See also L</find_or_create> and L</update_or_create>.
778 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
780 my $rsrc = $self->result_source;
783 if (exists $attrs->{key}) {
784 $constraint_name = defined $attrs->{key}
786 : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
790 # Parse out the condition from input
793 if (ref $_[0] eq 'HASH') {
794 $call_cond = { %{$_[0]} };
797 # if only values are supplied we need to default to 'primary'
798 $constraint_name = 'primary' unless defined $constraint_name;
800 my @c_cols = $rsrc->unique_constraint_columns($constraint_name);
802 $self->throw_exception(
803 "No constraint columns, maybe a malformed '$constraint_name' constraint?"
806 $self->throw_exception (
807 'find() expects either a column/value hashref, or a list of values '
808 . "corresponding to the columns of the specified unique constraint '$constraint_name'"
809 ) unless @c_cols == @_;
811 @{$call_cond}{@c_cols} = @_;
814 # process relationship data if any
815 for my $key (keys %$call_cond) {
817 length ref($call_cond->{$key})
819 my $relinfo = $rsrc->relationship_info($key)
821 # implicitly skip has_many's (likely MC)
822 ( ref( my $val = delete $call_cond->{$key} ) ne 'ARRAY' )
824 my ($rel_cond, $crosstable) = $rsrc->_resolve_condition(
825 $relinfo->{cond}, $val, $key, $key
828 $self->throw_exception("Complex condition via relationship '$key' is unsupported in find()")
829 if $crosstable or ref($rel_cond) ne 'HASH';
831 # supplement condition
832 # relationship conditions take precedence (?)
833 @{$call_cond}{keys %$rel_cond} = values %$rel_cond;
837 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
839 if (defined $constraint_name) {
840 $final_cond = $self->_qualify_cond_columns (
842 $rsrc->_minimal_valueset_satisfying_constraint(
843 constraint_name => $constraint_name,
844 values => ($self->_merge_with_rscond($call_cond))[0],
851 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
852 # This means that we got here after a merger of relationship conditions
853 # in ::Relationship::Base::search_related (the row method), and furthermore
854 # the relationship is of the 'single' type. This means that the condition
855 # provided by the relationship (already attached to $self) is sufficient,
856 # as there can be only one row in the database that would satisfy the
860 my (@unique_queries, %seen_column_combinations, $ci, @fc_exceptions);
862 # no key was specified - fall down to heuristics mode:
863 # run through all unique queries registered on the resultset, and
864 # 'OR' all qualifying queries together
866 # always start from 'primary' if it exists at all
867 for my $c_name ( sort {
869 : $b eq 'primary' ? 1
871 } $rsrc->unique_constraint_names) {
873 next if $seen_column_combinations{
874 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
878 push @unique_queries, $self->_qualify_cond_columns(
879 $rsrc->_minimal_valueset_satisfying_constraint(
880 constraint_name => $c_name,
881 values => ($self->_merge_with_rscond($call_cond))[0],
882 columns_info => ($ci ||= $rsrc->columns_info),
888 push @fc_exceptions, $_ if $_ =~ /\bFilterColumn\b/;
893 @unique_queries ? \@unique_queries
894 : @fc_exceptions ? $self->throw_exception(join "; ", map { $_ =~ /(.*) at .+ line \d+$/s } @fc_exceptions )
895 : $self->_non_unique_find_fallback ($call_cond, $attrs)
899 # Run the query, passing the result_class since it should propagate for find
900 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
901 if ($rs->_resolved_attrs->{collapse}) {
903 carp "Query returned more than one row" if $rs->next;
911 # This is a stop-gap method as agreed during the discussion on find() cleanup:
912 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
914 # It is invoked when find() is called in legacy-mode with insufficiently-unique
915 # condition. It is provided for overrides until a saner way forward is devised
917 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
918 # the road. Please adjust your tests accordingly to catch this situation early
919 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
921 # The method will not be removed without an adequately complete replacement
922 # for strict-mode enforcement
923 sub _non_unique_find_fallback {
924 my ($self, $cond, $attrs) = @_;
926 return $self->_qualify_cond_columns(
928 exists $attrs->{alias}
930 : $self->{attrs}{alias}
935 sub _qualify_cond_columns {
936 my ($self, $cond, $alias) = @_;
938 my %aliased = %$cond;
939 for (keys %aliased) {
940 $aliased{"$alias.$_"} = delete $aliased{$_}
947 sub _build_unique_cond {
949 '_build_unique_cond is a private method, and moreover is about to go '
950 . 'away. Please contact the development team at %s if you believe you '
951 . 'have a genuine use for this method, in order to discuss alternatives.',
952 DBIx::Class::_ENV_::HELP_URL,
955 my ($self, $constraint_name, $cond, $croak_on_null) = @_;
957 $self->result_source->_minimal_valueset_satisfying_constraint(
958 constraint_name => $constraint_name,
960 carp_on_nulls => !$croak_on_null
964 =head2 search_related
968 =item Arguments: $rel_name, $cond?, L<\%attrs?|/ATTRIBUTES>
970 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
974 $new_rs = $cd_rs->search_related('artist', {
978 Searches the specified relationship, optionally specifying a condition and
979 attributes for matching records. See L</ATTRIBUTES> for more information.
981 In list context, C<< ->all() >> is called implicitly on the resultset, thus
982 returning a list of result objects instead. To avoid that, use L</search_related_rs>.
984 See also L</search_related_rs>.
988 sub search_related :DBIC_method_is_indirect_sugar {
989 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
990 return shift->related_resultset(shift)->search(@_);
993 =head2 search_related_rs
995 This method works exactly the same as search_related, except that
996 it guarantees a resultset, even in list context.
1000 sub search_related_rs :DBIC_method_is_indirect_sugar {
1001 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1002 return shift->related_resultset(shift)->search_rs(@_);
1009 =item Arguments: none
1011 =item Return Value: L<$cursor|DBIx::Class::Cursor>
1015 Returns a storage-driven cursor to the given resultset. See
1016 L<DBIx::Class::Cursor> for more information.
1023 return $self->{cursor} ||= do {
1024 my $attrs = $self->_resolved_attrs;
1025 $self->result_source->schema->storage->select(
1026 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
1035 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1037 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1041 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1043 Inflates the first result without creating a cursor if the resultset has
1044 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1047 While this method can take an optional search condition (just like L</search>)
1048 being a fast-code-path it does not recognize search attributes. If you need to
1049 add extra joins or similar, call L</search> and then chain-call L</single> on the
1050 L<DBIx::Class::ResultSet> returned.
1056 As of 0.08100, this method enforces the assumption that the preceding
1057 query returns only one row. If more than one row is returned, you will receive
1060 Query returned more than one row
1062 In this case, you should be using L</next> or L</find> instead, or if you really
1063 know what you are doing, use the L</rows> attribute to explicitly limit the size
1066 This method will also throw an exception if it is called on a resultset prefetching
1067 has_many, as such a prefetch implies fetching multiple rows from the database in
1068 order to assemble the resulting object.
1075 my ($self, $where) = @_;
1077 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1080 my $attrs = { %{$self->_resolved_attrs} };
1082 $self->throw_exception(
1083 'single() can not be used on resultsets collapsing a has_many. Use find( \%cond ) or next() instead'
1084 ) if $attrs->{collapse};
1087 if (defined $attrs->{where}) {
1090 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1091 $where, delete $attrs->{where} ]
1094 $attrs->{where} = $where;
1098 my $data = [ $self->result_source->schema->storage->select_single(
1099 $attrs->{from}, $attrs->{select},
1100 $attrs->{where}, $attrs
1103 return undef unless @$data;
1104 $self->{_stashed_rows} = [ $data ];
1105 $self->_construct_results->[0];
1112 =item Arguments: L<$cond?|DBIx::Class::SQLMaker>
1114 =item Return Value: L<$resultsetcolumn|DBIx::Class::ResultSetColumn>
1118 my $max_length = $rs->get_column('length')->max;
1120 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1125 DBIx::Class::ResultSetColumn->new(@_);
1132 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1134 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1138 # WHERE title LIKE '%blue%'
1139 $cd_rs = $rs->search_like({ title => '%blue%'});
1141 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1142 that this is simply a convenience method retained for ex Class::DBI users.
1143 You most likely want to use L</search> with specific operators.
1145 For more information, see L<DBIx::Class::Manual::Cookbook>.
1147 This method is deprecated and will be removed in 0.09. Use L<search()|/search>
1148 instead. An example conversion is:
1150 ->search_like({ foo => 'bar' });
1154 ->search({ foo => { like => 'bar' } });
1161 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1162 .' Instead use ->search({ x => { -like => "y%" } })'
1163 .' (note the outer pair of {}s - they are important!)'
1165 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
1166 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1167 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1168 return $class->search($query, { %$attrs });
1175 =item Arguments: $first, $last
1177 =item Return Value: L<$resultset|/search> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context)
1181 Returns a resultset or object list representing a subset of elements from the
1182 resultset slice is called on. Indexes are from 0, i.e., to get the first
1183 three records, call:
1185 my ($one, $two, $three) = $rs->slice(0, 2);
1190 my ($self, $min, $max) = @_;
1191 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1192 $attrs->{offset} = $self->{attrs}{offset} || 0;
1193 $attrs->{offset} += $min;
1194 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1195 return $self->search(undef, $attrs);
1202 =item Arguments: none
1204 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1208 Returns the next element in the resultset (C<undef> is there is none).
1210 Can be used to efficiently iterate over records in the resultset:
1212 my $rs = $schema->resultset('CD')->search;
1213 while (my $cd = $rs->next) {
1217 Note that you need to store the resultset object, and call C<next> on it.
1218 Calling C<< resultset('Table')->next >> repeatedly will always return the
1219 first record from the resultset.
1226 if (my $cache = $self->get_cache) {
1227 $self->{all_cache_position} ||= 0;
1228 return $cache->[$self->{all_cache_position}++];
1231 if ($self->{attrs}{cache}) {
1232 delete $self->{pager};
1233 $self->{all_cache_position} = 1;
1234 return ($self->all)[0];
1237 return shift(@{$self->{_stashed_results}}) if @{ $self->{_stashed_results}||[] };
1239 $self->{_stashed_results} = $self->_construct_results
1242 return shift @{$self->{_stashed_results}};
1245 # Constructs as many results as it can in one pass while respecting
1246 # cursor laziness. Several modes of operation:
1248 # * Always builds everything present in @{$self->{_stashed_rows}}
1249 # * If called with $fetch_all true - pulls everything off the cursor and
1250 # builds all result structures (or objects) in one pass
1251 # * If $self->_resolved_attrs->{collapse} is true, checks the order_by
1252 # and if the resultset is ordered properly by the left side:
1253 # * Fetches stuff off the cursor until the "master object" changes,
1254 # and saves the last extra row (if any) in @{$self->{_stashed_rows}}
1256 # * Just fetches, and collapses/constructs everything as if $fetch_all
1257 # was requested (there is no other way to collapse except for an
1259 # * If no collapse is requested - just get the next row, construct and
1261 sub _construct_results {
1262 my ($self, $fetch_all) = @_;
1264 my $rsrc = $self->result_source;
1265 my $attrs = $self->_resolved_attrs;
1270 ! $attrs->{order_by}
1274 my @pcols = $rsrc->primary_columns
1276 # default order for collapsing unless the user asked for something
1277 $attrs->{order_by} = [ map { join '.', $attrs->{alias}, $_} @pcols ];
1278 $attrs->{_ordered_for_collapse} = 1;
1279 $attrs->{_order_is_artificial} = 1;
1282 # this will be used as both initial raw-row collector AND as a RV of
1283 # _construct_results. Not regrowing the array twice matters a lot...
1284 # a surprising amount actually
1285 my $rows = delete $self->{_stashed_rows};
1287 my $cursor; # we may not need one at all
1289 my $did_fetch_all = $fetch_all;
1292 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1293 $rows = [ ($rows ? @$rows : ()), $self->cursor->all ];
1295 elsif( $attrs->{collapse} ) {
1297 # a cursor will need to be closed over in case of collapse
1298 $cursor = $self->cursor;
1300 $attrs->{_ordered_for_collapse} = (
1306 ->_extract_colinfo_of_stable_main_source_order_by_portion($attrs)
1308 ) unless defined $attrs->{_ordered_for_collapse};
1310 if (! $attrs->{_ordered_for_collapse}) {
1313 # instead of looping over ->next, use ->all in stealth mode
1314 # *without* calling a ->reset afterwards
1315 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1316 if (! $cursor->{_done}) {
1317 $rows = [ ($rows ? @$rows : ()), $cursor->all ];
1318 $cursor->{_done} = 1;
1323 if (! $did_fetch_all and ! @{$rows||[]} ) {
1324 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1325 $cursor ||= $self->cursor;
1326 if (scalar (my @r = $cursor->next) ) {
1331 return undef unless @{$rows||[]};
1333 # sanity check - people are too clever for their own good
1334 if ($attrs->{collapse} and my $aliastypes = $attrs->{_last_sqlmaker_alias_map} ) {
1336 my $multiplied_selectors;
1337 for my $sel_alias ( grep { $_ ne $attrs->{alias} } keys %{ $aliastypes->{selecting} } ) {
1339 $aliastypes->{multiplying}{$sel_alias}
1341 $aliastypes->{premultiplied}{$sel_alias}
1343 $multiplied_selectors->{$_} = 1 for values %{$aliastypes->{selecting}{$sel_alias}{-seen_columns}}
1347 for my $i (0 .. $#{$attrs->{as}} ) {
1348 my $sel = $attrs->{select}[$i];
1350 if (ref $sel eq 'SCALAR') {
1353 elsif( ref $sel eq 'REF' and ref $$sel eq 'ARRAY' ) {
1357 $self->throw_exception(
1358 'Result collapse not possible - selection from a has_many source redirected to the main object'
1359 ) if ($multiplied_selectors->{$sel} and $attrs->{as}[$i] !~ /\./);
1363 # hotspot - skip the setter
1364 my $res_class = $self->_result_class;
1366 my $inflator_cref = $self->{_result_inflator}{cref} ||= do {
1367 $res_class->can ('inflate_result')
1368 or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
1371 my $infmap = $attrs->{as};
1373 $self->{_result_inflator}{is_core_row} = ( (
1376 ( \&DBIx::Class::Row::inflate_result || die "No ::Row::inflate_result() - can't happen" )
1377 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_core_row};
1379 $self->{_result_inflator}{is_hri} = ( (
1380 ! $self->{_result_inflator}{is_core_row}
1382 $inflator_cref == \&DBIx::Class::ResultClass::HashRefInflator::inflate_result
1383 ) ? 1 : 0 ) unless defined $self->{_result_inflator}{is_hri};
1386 if ($attrs->{_simple_passthrough_construction}) {
1387 # construct a much simpler array->hash folder for the one-table HRI cases right here
1388 if ($self->{_result_inflator}{is_hri}) {
1389 for my $r (@$rows) {
1390 $r = { map { $infmap->[$_] => $r->[$_] } 0..$#$infmap };
1393 # FIXME SUBOPTIMAL this is a very very very hot spot
1394 # while rather optimal we can *still* do much better, by
1395 # building a smarter Row::inflate_result(), and
1396 # switch to feeding it data via a much leaner interface
1398 # crude unscientific benchmarking indicated the shortcut eval is not worth it for
1399 # this particular resultset size
1400 elsif ( $self->{_result_inflator}{is_core_row} and @$rows < 60 ) {
1401 for my $r (@$rows) {
1402 $r = $inflator_cref->($res_class, $rsrc, { map { $infmap->[$_] => $r->[$_] } (0..$#$infmap) } );
1407 ( $self->{_result_inflator}{is_core_row}
1408 ? '$_ = $inflator_cref->($res_class, $rsrc, { %s }) for @$rows'
1409 # a custom inflator may be a multiplier/reductor - put it in direct list ctx
1410 : '@$rows = map { $inflator_cref->($res_class, $rsrc, { %s } ) } @$rows'
1412 ( join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap ) )
1418 $self->{_result_inflator}{is_hri} ? 'hri'
1419 : $self->{_result_inflator}{is_core_row} ? 'classic_pruning'
1420 : 'classic_nonpruning'
1423 unless( $self->{_row_parser}{$parser_type}{cref} ) {
1425 # $args and $attrs to _mk_row_parser are separated to delineate what is
1426 # core collapser stuff and what is dbic $rs specific
1427 $self->{_row_parser}{$parser_type}{src} = $rsrc->_mk_row_parser({
1428 inflate_map => $infmap,
1429 collapse => $attrs->{collapse},
1430 premultiplied => $attrs->{_main_source_premultiplied},
1431 hri_style => $self->{_result_inflator}{is_hri},
1432 prune_null_branches => $self->{_result_inflator}{is_hri} || $self->{_result_inflator}{is_core_row},
1435 $self->{_row_parser}{$parser_type}{cref} = do {
1436 package # hide form PAUSE
1437 DBIx::Class::__GENERATED_ROW_PARSER__;
1439 eval $self->{_row_parser}{$parser_type}{src};
1443 # this needs to close over the *current* cursor, hence why it is not cached above
1444 my $next_cref = ($did_fetch_all or ! $attrs->{collapse})
1447 # FIXME SUBOPTIMAL - we can do better, cursor->next/all (well diff. methods) should return a ref
1448 my @r = $cursor->next or return;
1453 $self->{_row_parser}{$parser_type}{cref}->(
1456 ( $self->{_stashed_rows} = [] ),
1457 ( my $null_violations = {} ),
1460 $self->throw_exception(
1461 'Collapse aborted - the following columns are declared (or defaulted to) '
1462 . 'non-nullable within DBIC but NULLs were retrieved from storage: '
1463 . join( ', ', map { "'$infmap->[$_]'" } sort { $a <=> $b } keys %$null_violations )
1464 . ' within data row ' . dump_value({
1467 ( ! defined $self->{_stashed_rows}[0][$_] or length $self->{_stashed_rows}[0][$_] < 50 )
1468 ? $self->{_stashed_rows}[0][$_]
1469 : substr( $self->{_stashed_rows}[0][$_], 0, 50 ) . '...'
1470 } 0 .. $#{$self->{_stashed_rows}[0]}
1472 ) if keys %$null_violations;
1474 # simple in-place substitution, does not regrow $rows
1475 if ($self->{_result_inflator}{is_core_row}) {
1476 $_ = $inflator_cref->($res_class, $rsrc, @$_) for @$rows
1478 # Special-case multi-object HRI - there is no $inflator_cref pass at all
1479 elsif ( ! $self->{_result_inflator}{is_hri} ) {
1480 # the inflator may be a multiplier/reductor - put it in list ctx
1481 @$rows = map { $inflator_cref->($res_class, $rsrc, @$_) } @$rows;
1485 # The @$rows check seems odd at first - why wouldn't we want to warn
1486 # regardless? The issue is things like find() etc, where the user
1487 # *knows* only one result will come back. In these cases the ->all
1488 # is not a pessimization, but rather something we actually want
1490 'Unable to properly collapse has_many results in iterator mode due '
1491 . 'to order criteria - performed an eager cursor slurp underneath. '
1492 . 'Consider using ->all() instead'
1493 ) if ( ! $fetch_all and @$rows > 1 );
1498 =head2 result_source
1502 =item Arguments: L<$result_source?|DBIx::Class::ResultSource>
1504 =item Return Value: L<$result_source|DBIx::Class::ResultSource>
1508 An accessor for the primary ResultSource object from which this ResultSet
1515 =item Arguments: $result_class?
1517 =item Return Value: $result_class
1521 An accessor for the class to use when creating result objects. Defaults to
1522 C<< result_source->result_class >> - which in most cases is the name of the
1523 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1525 Note that changing the result_class will also remove any components
1526 that were originally loaded in the source class via
1527 L<load_components|Class::C3::Componentised/load_components( @comps )>.
1528 Any overloaded methods in the original source class will not run.
1533 my ($self, $result_class) = @_;
1534 if ($result_class) {
1536 # don't fire this for an object
1537 $self->ensure_class_loaded($result_class)
1538 unless ref($result_class);
1540 if ($self->get_cache) {
1541 carp_unique('Changing the result_class of a ResultSet instance with cached results is a noop - the cache contents will not be altered');
1543 # FIXME ENCAPSULATION - encapsulation breach, cursor method additions pending
1544 elsif ($self->{cursor} && $self->{cursor}{_pos}) {
1545 $self->throw_exception('Changing the result_class of a ResultSet instance with an active cursor is not supported');
1548 $self->_result_class($result_class);
1550 delete $self->{_result_inflator};
1552 $self->_result_class;
1559 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1561 =item Return Value: $count
1565 Performs an SQL C<COUNT> with the same query as the resultset was built
1566 with to find the number of elements. Passing arguments is equivalent to
1567 C<< $rs->search ($cond, \%attrs)->count >>
1573 return $self->search(@_)->count if @_ and defined $_[0];
1574 return scalar @{ $self->get_cache } if $self->get_cache;
1576 my $attrs = { %{ $self->_resolved_attrs } };
1578 # this is a little optimization - it is faster to do the limit
1579 # adjustments in software, instead of a subquery
1580 my ($rows, $offset) = delete @{$attrs}{qw/rows offset/};
1583 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1584 $crs = $self->_count_subq_rs ($attrs);
1587 $crs = $self->_count_rs ($attrs);
1589 my $count = $crs->next;
1591 $count -= $offset if $offset;
1592 $count = $rows if $rows and $rows < $count;
1593 $count = 0 if ($count < 0);
1602 =item Arguments: L<$cond|DBIx::Class::SQLMaker>, L<\%attrs?|/ATTRIBUTES>
1604 =item Return Value: L<$count_rs|DBIx::Class::ResultSetColumn>
1608 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1609 This can be very handy for subqueries:
1611 ->search( { amount => $some_rs->count_rs->as_query } )
1613 As with regular resultsets the SQL query will be executed only after
1614 the resultset is accessed via L</next> or L</all>. That would return
1615 the same single value obtainable via L</count>.
1621 return $self->search(@_)->count_rs if @_;
1623 # this may look like a lack of abstraction (count() does about the same)
1624 # but in fact an _rs *must* use a subquery for the limits, as the
1625 # software based limiting can not be ported if this $rs is to be used
1626 # in a subquery itself (i.e. ->as_query)
1627 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1628 return $self->_count_subq_rs($self->{_attrs});
1631 return $self->_count_rs($self->{_attrs});
1636 # returns a ResultSetColumn object tied to the count query
1639 my ($self, $attrs) = @_;
1641 my $rsrc = $self->result_source;
1643 my $tmp_attrs = { %$attrs };
1644 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1645 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1647 # overwrite the selector (supplied by the storage)
1648 $rsrc->resultset_class->new($rsrc, {
1650 select => $rsrc->schema->storage->_count_select ($rsrc, $attrs),
1652 })->get_column ('count');
1656 # same as above but uses a subquery
1658 sub _count_subq_rs {
1659 my ($self, $attrs) = @_;
1661 my $rsrc = $self->result_source;
1663 my $sub_attrs = { %$attrs };
1664 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1665 delete @{$sub_attrs}{qw/collapse columns as select order_by for/};
1667 # if we multi-prefetch we group_by something unique, as this is what we would
1668 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1669 if ( $attrs->{collapse} ) {
1670 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1671 $rsrc->_identifying_column_set || $self->throw_exception(
1672 'Unable to construct a unique group_by criteria properly collapsing the '
1673 . 'has_many prefetch before count()'
1678 # Calculate subquery selector
1679 if (my $g = $sub_attrs->{group_by}) {
1681 my $sql_maker = $rsrc->schema->storage->sql_maker;
1683 # necessary as the group_by may refer to aliased functions
1685 for my $sel (@{$attrs->{select}}) {
1686 $sel_index->{$sel->{-as}} = $sel
1687 if (ref $sel eq 'HASH' and $sel->{-as});
1690 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1691 # also look for named aggregates referred in the having clause
1692 # having often contains scalarrefs - thus parse it out entirely
1694 if ($attrs->{having}) {
1695 local $sql_maker->{having_bind};
1696 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1697 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1698 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1699 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1700 # if we don't unset it we screw up retarded but unfortunately working
1701 # 'MAX(foo.bar)' => { '>', 3 }
1702 $sql_maker->{name_sep} = '';
1705 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1707 my $having_sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1710 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1711 # and if all fails for an utterly naive quoted scalar-with-function
1712 while ($having_sql =~ /
1713 $rquote $sep $lquote (.+?) $rquote
1715 [\s,] \w+ \. (\w+) [\s,]
1717 [\s,] $lquote (.+?) $rquote [\s,]
1719 my $part = $1 || $2 || $3; # one of them matched if we got here
1720 unless ($seen_having{$part}++) {
1727 my $colpiece = $sel_index->{$_} || $_;
1729 # unqualify join-based group_by's. Arcane but possible query
1730 # also horrible horrible hack to alias a column (not a func.)
1731 # (probably need to introduce SQLA syntax)
1732 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1735 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1737 push @{$sub_attrs->{select}}, $colpiece;
1741 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1742 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1745 return $rsrc->resultset_class
1746 ->new ($rsrc, $sub_attrs)
1748 ->search ({}, { columns => { count => $rsrc->schema->storage->_count_select ($rsrc, $attrs) } })
1749 ->get_column ('count');
1753 =head2 count_literal
1755 B<CAVEAT>: C<count_literal> is provided for Class::DBI compatibility and
1756 should only be used in that context. See L</search_literal> for further info.
1760 =item Arguments: $sql_fragment, @standalone_bind_values
1762 =item Return Value: $count
1766 Counts the results in a literal query. Equivalent to calling L</search_literal>
1767 with the passed arguments, then L</count>.
1771 sub count_literal :DBIC_method_is_indirect_sugar {
1772 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1773 shift->search_literal(@_)->count
1780 =item Arguments: none
1782 =item Return Value: L<@result_objs|DBIx::Class::Manual::ResultClass>
1786 Returns all elements in the resultset.
1793 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1796 delete @{$self}{qw/_stashed_rows _stashed_results/};
1798 if (my $c = $self->get_cache) {
1802 $self->cursor->reset;
1804 my $objs = $self->_construct_results('fetch_all') || [];
1806 $self->set_cache($objs) if $self->{attrs}{cache};
1815 =item Arguments: none
1817 =item Return Value: $self
1821 Resets the resultset's cursor, so you can iterate through the elements again.
1822 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1830 delete @{$self}{qw/_stashed_rows _stashed_results/};
1831 $self->{all_cache_position} = 0;
1832 $self->cursor->reset;
1840 =item Arguments: none
1842 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef
1846 L<Resets|/reset> the resultset (causing a fresh query to storage) and returns
1847 an object for the first result (or C<undef> if the resultset is empty).
1851 sub first :DBIC_method_is_indirect_sugar {
1852 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
1853 return $_[0]->reset->next;
1859 # Determines whether and what type of subquery is required for the $rs operation.
1860 # If grouping is necessary either supplies its own, or verifies the current one
1861 # After all is done delegates to the proper storage method.
1863 sub _rs_update_delete {
1864 my ($self, $op, $values) = @_;
1866 my $rsrc = $self->result_source;
1867 my $storage = $rsrc->schema->storage;
1869 my $attrs = { %{$self->_resolved_attrs} };
1871 my $join_classifications;
1872 my ($existing_group_by) = delete @{$attrs}{qw(group_by _grouped_by_distinct)};
1874 # do we need a subquery for any reason?
1876 defined $existing_group_by
1878 # if {from} is unparseable wrap a subq
1879 ref($attrs->{from}) ne 'ARRAY'
1881 # limits call for a subq
1882 $self->_has_resolved_attr(qw/rows offset/)
1885 # simplify the joinmap, so we can further decide if a subq is necessary
1886 if (!$needs_subq and @{$attrs->{from}} > 1) {
1888 ($attrs->{from}, $join_classifications) =
1889 $storage->_prune_unused_joins ($attrs);
1891 # any non-pruneable non-local restricting joins imply subq
1892 $needs_subq = grep { $_ ne $attrs->{alias} } keys %{ $join_classifications->{restricting} || {} };
1895 # check if the head is composite (by now all joins are thrown out unless $needs_subq)
1897 (ref $attrs->{from}[0]) ne 'HASH'
1899 ref $attrs->{from}[0]{ $attrs->{from}[0]{-alias} }
1903 # do we need anything like a subquery?
1904 if (! $needs_subq) {
1905 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1906 # a condition containing 'me' or other table prefixes will not work
1907 # at all. Tell SQLMaker to dequalify idents via a gross hack.
1909 my $sqla = $rsrc->schema->storage->sql_maker;
1910 local $sqla->{_dequalify_idents} = 1;
1911 \[ $sqla->_recurse_where($self->{cond}) ];
1915 # we got this far - means it is time to wrap a subquery
1916 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1918 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1924 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1925 delete $attrs->{$_} for qw/select as collapse/;
1926 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1928 # this will be consumed by the pruner waaaaay down the stack
1929 $attrs->{_force_prune_multiplying_joins} = 1;
1931 my $subrs = (ref $self)->new($rsrc, $attrs);
1933 if (@$idcols == 1) {
1934 $cond = { $idcols->[0] => { -in => $subrs->as_query } };
1936 elsif ($storage->_use_multicolumn_in) {
1937 # no syntax for calling this properly yet
1938 # !!! EXPERIMENTAL API !!! WILL CHANGE !!!
1939 $cond = $storage->sql_maker->_where_op_multicolumn_in (
1940 $idcols, # how do I convey a list of idents...? can binds reside on lhs?
1945 # if all else fails - get all primary keys and operate over a ORed set
1946 # wrap in a transaction for consistency
1947 # this is where the group_by/multiplication starts to matter
1951 # we do not need to check pre-multipliers, since if the premulti is there, its
1952 # parent (who is multi) will be there too
1953 keys %{ $join_classifications->{multiplying} || {} }
1955 # make sure if there is a supplied group_by it matches the columns compiled above
1956 # perfectly. Anything else can not be sanely executed on most databases so croak
1957 # right then and there
1958 if ($existing_group_by) {
1959 my @current_group_by = map
1960 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1965 join ("\x00", sort @current_group_by)
1967 join ("\x00", sort @{$attrs->{columns}} )
1969 $self->throw_exception (
1970 "You have just attempted a $op operation on a resultset which does group_by"
1971 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1972 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1973 . ' kind of queries. Please retry the operation with a modified group_by or'
1974 . ' without using one at all.'
1979 $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
1982 $guard = $storage->txn_scope_guard;
1984 for my $row ($subrs->cursor->all) {
1986 { $idcols->[$_] => $row->[$_] }
1993 my $res = $cond ? $storage->$op (
1995 $op eq 'update' ? $values : (),
1999 $guard->commit if $guard;
2008 =item Arguments: \%values
2010 =item Return Value: $underlying_storage_rv
2014 Sets the specified columns in the resultset to the supplied values in a
2015 single query. Note that this will not run any accessor/set_column/update
2016 triggers, nor will it update any result object instances derived from this
2017 resultset (this includes the contents of the L<resultset cache|/set_cache>
2018 if any). See L</update_all> if you need to execute any on-update
2019 triggers or cascades defined either by you or a
2020 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2022 The return value is a pass through of what the underlying
2023 storage backend returned, and may vary. See L<DBI/execute> for the most
2028 Note that L</update> does not process/deflate any of the values passed in.
2029 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
2030 ensure manually that any value passed to this method will stringify to
2031 something the RDBMS knows how to deal with. A notable example is the
2032 handling of L<DateTime> objects, for more info see:
2033 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
2038 my ($self, $values) = @_;
2039 $self->throw_exception('Values for update must be a hash')
2040 unless ref $values eq 'HASH';
2042 return $self->_rs_update_delete ('update', $values);
2049 =item Arguments: \%values
2051 =item Return Value: 1
2055 Fetches all objects and updates them one at a time via
2056 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
2057 triggers, while L</update> will not.
2062 my ($self, $values) = @_;
2063 $self->throw_exception('Values for update_all must be a hash')
2064 unless ref $values eq 'HASH';
2066 my $guard = $self->result_source->schema->txn_scope_guard;
2067 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
2076 =item Arguments: none
2078 =item Return Value: $underlying_storage_rv
2082 Deletes the rows matching this resultset in a single query. Note that this
2083 will not run any delete triggers, nor will it alter the
2084 L<in_storage|DBIx::Class::Row/in_storage> status of any result object instances
2085 derived from this resultset (this includes the contents of the
2086 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
2087 execute any on-delete triggers or cascades defined either by you or a
2088 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
2090 The return value is a pass through of what the underlying storage backend
2091 returned, and may vary. See L<DBI/execute> for the most common case.
2097 $self->throw_exception('delete does not accept any arguments')
2100 return $self->_rs_update_delete ('delete');
2107 =item Arguments: none
2109 =item Return Value: 1
2113 Fetches all objects and deletes them one at a time via
2114 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2115 triggers, while L</delete> will not.
2121 $self->throw_exception('delete_all does not accept any arguments')
2124 my $guard = $self->result_source->schema->txn_scope_guard;
2125 $_->delete for $self->all;
2134 =item Arguments: [ \@column_list, \@row_values+ ] | [ \%col_data+ ]
2136 =item Return Value: L<\@result_objects|DBIx::Class::Manual::ResultClass> (scalar context) | L<@result_objects|DBIx::Class::Manual::ResultClass> (list context)
2140 Accepts either an arrayref of hashrefs or alternatively an arrayref of
2147 The context of this method call has an important effect on what is
2148 submitted to storage. In void context data is fed directly to fastpath
2149 insertion routines provided by the underlying storage (most often
2150 L<DBI/execute_for_fetch>), bypassing the L<new|DBIx::Class::Row/new> and
2151 L<insert|DBIx::Class::Row/insert> calls on the
2152 L<Result|DBIx::Class::Manual::ResultClass> class, including any
2153 augmentation of these methods provided by components. For example if you
2154 are using something like L<DBIx::Class::UUIDColumns> to create primary
2155 keys for you, you will find that your PKs are empty. In this case you
2156 will have to explicitly force scalar or list context in order to create
2161 In non-void (scalar or list) context, this method is simply a wrapper
2162 for L</create>. Depending on list or scalar context either a list of
2163 L<Result|DBIx::Class::Manual::ResultClass> objects or an arrayref
2164 containing these objects is returned.
2166 When supplying data in "arrayref of arrayrefs" invocation style, the
2167 first element should be a list of column names and each subsequent
2168 element should be a data value in the earlier specified column order.
2171 $schema->resultset("Artist")->populate([
2172 [ qw( artistid name ) ],
2173 [ 100, 'A Formally Unknown Singer' ],
2174 [ 101, 'A singer that jumped the shark two albums ago' ],
2175 [ 102, 'An actually cool singer' ],
2178 For the arrayref of hashrefs style each hashref should be a structure
2179 suitable for passing to L</create>. Multi-create is also permitted with
2182 $schema->resultset("Artist")->populate([
2183 { artistid => 4, name => 'Manufactured Crap', cds => [
2184 { title => 'My First CD', year => 2006 },
2185 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2188 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2189 { title => 'My parents sold me to a record company', year => 2005 },
2190 { title => 'Why Am I So Ugly?', year => 2006 },
2191 { title => 'I Got Surgery and am now Popular', year => 2007 }
2196 If you attempt a void-context multi-create as in the example above (each
2197 Artist also has the related list of CDs), and B<do not> supply the
2198 necessary autoinc foreign key information, this method will proxy to the
2199 less efficient L</create>, and then throw the Result objects away. In this
2200 case there are obviously no benefits to using this method over L</create>.
2207 # this is naive and just a quick check
2208 # the types will need to be checked more thoroughly when the
2209 # multi-source populate gets added
2211 ref $_[0] eq 'ARRAY'
2213 ( @{$_[0]} or return )
2215 ( ref $_[0][0] eq 'HASH' or ref $_[0][0] eq 'ARRAY' )
2218 ) or $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2220 # FIXME - no cref handling
2221 # At this point assume either hashes or arrays
2223 my $rsrc = $self->result_source;
2225 if(defined wantarray) {
2226 my (@results, $guard);
2228 if (ref $data->[0] eq 'ARRAY') {
2229 # column names only, nothing to do
2230 return if @$data == 1;
2232 $guard = $rsrc->schema->storage->txn_scope_guard
2236 { my $vals = $_; $self->new_result({ map { $data->[0][$_] => $vals->[$_] } 0..$#{$data->[0]} })->insert }
2237 @{$data}[1 .. $#$data]
2242 $guard = $rsrc->schema->storage->txn_scope_guard
2245 @results = map { $self->new_result($_)->insert } @$data;
2248 $guard->commit if $guard;
2249 return wantarray ? @results : \@results;
2252 # we have to deal with *possibly incomplete* related data
2253 # this means we have to walk the data structure twice
2254 # whether we want this or not
2255 # jnap, I hate you ;)
2256 my $rel_info = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2258 my ($colinfo, $colnames, $slices_with_rels);
2262 for my $i (0 .. $#$data) {
2264 my $current_slice_seen_rel_infos;
2266 ### Determine/Supplement collists
2267 ### BEWARE - This is a hot piece of code, a lot of weird idioms were used
2268 if( ref $data->[$i] eq 'ARRAY' ) {
2270 # positional(!) explicit column list
2272 # column names only, nothing to do
2273 return if @$data == 1;
2275 $colinfo->{$data->[0][$_]} = { pos => $_, name => $data->[0][$_] } and push @$colnames, $data->[0][$_]
2276 for 0 .. $#{$data->[0]};
2283 for (values %$colinfo) {
2284 if ($_->{is_rel} ||= (
2285 $rel_info->{$_->{name}}
2288 ref $data->[$i][$_->{pos}] eq 'ARRAY'
2290 ref $data->[$i][$_->{pos}] eq 'HASH'
2292 ( defined blessed $data->[$i][$_->{pos}] and $data->[$i][$_->{pos}]->isa('DBIx::Class::Row') )
2298 # moar sanity check... sigh
2299 for ( ref $data->[$i][$_->{pos}] eq 'ARRAY' ? @{$data->[$i][$_->{pos}]} : $data->[$i][$_->{pos}] ) {
2300 if ( defined blessed $_ and $_->isa('DBIx::Class::Row' ) ) {
2301 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2302 return my $throwaway = $self->populate(@_);
2306 push @$current_slice_seen_rel_infos, $rel_info->{$_->{name}};
2311 if ($current_slice_seen_rel_infos) {
2312 push @$slices_with_rels, { map { $colnames->[$_] => $data->[$i][$_] } 0 .. $#$colnames };
2314 # this is needed further down to decide whether or not to fallback to create()
2315 $colinfo->{$colnames->[$_]}{seen_null} ||= ! defined $data->[$i][$_]
2316 for 0 .. $#$colnames;
2319 elsif( ref $data->[$i] eq 'HASH' ) {
2321 for ( sort keys %{$data->[$i]} ) {
2323 $colinfo->{$_} ||= do {
2325 $self->throw_exception("Column '$_' must be present in supplied explicit column list")
2326 if $data_start; # it will be 0 on AoH, 1 on AoA
2328 push @$colnames, $_;
2331 { pos => $#$colnames, name => $_ }
2334 if ($colinfo->{$_}{is_rel} ||= (
2338 ref $data->[$i]{$_} eq 'ARRAY'
2340 ref $data->[$i]{$_} eq 'HASH'
2342 ( defined blessed $data->[$i]{$_} and $data->[$i]{$_}->isa('DBIx::Class::Row') )
2348 # moar sanity check... sigh
2349 for ( ref $data->[$i]{$_} eq 'ARRAY' ? @{$data->[$i]{$_}} : $data->[$i]{$_} ) {
2350 if ( defined blessed $_ and $_->isa('DBIx::Class::Row' ) ) {
2351 carp_unique("Fast-path populate() with supplied related objects is not possible - falling back to regular create()");
2352 return my $throwaway = $self->populate(@_);
2356 push @$current_slice_seen_rel_infos, $rel_info->{$_};
2360 if ($current_slice_seen_rel_infos) {
2361 push @$slices_with_rels, $data->[$i];
2363 # this is needed further down to decide whether or not to fallback to create()
2364 $colinfo->{$_}{seen_null} ||= ! defined $data->[$i]{$_}
2365 for keys %{$data->[$i]};
2369 $self->throw_exception('Unexpected populate() data structure member type: ' . ref $data->[$i] );
2373 { $_->{attrs}{is_depends_on} }
2374 @{ $current_slice_seen_rel_infos || [] }
2376 carp_unique("Fast-path populate() of belongs_to relationship data is not possible - falling back to regular create()");
2377 return my $throwaway = $self->populate(@_);
2381 if( $slices_with_rels ) {
2383 # need to exclude the rel "columns"
2384 $colnames = [ grep { ! $colinfo->{$_}{is_rel} } @$colnames ];
2386 # extra sanity check - ensure the main source is in fact identifiable
2387 # the localizing of nullability is insane, but oh well... the use-case is legit
2388 my $ci = $rsrc->columns_info($colnames);
2390 $ci->{$_} = { %{$ci->{$_}}, is_nullable => 0 }
2391 for grep { ! $colinfo->{$_}{seen_null} } keys %$ci;
2393 unless( $rsrc->_identifying_column_set($ci) ) {
2394 carp_unique("Fast-path populate() of non-uniquely identifiable rows with related data is not possible - falling back to regular create()");
2395 return my $throwaway = $self->populate(@_);
2399 ### inherit the data locked in the conditions of the resultset
2400 my ($rs_data) = $self->_merge_with_rscond({});
2401 delete @{$rs_data}{@$colnames}; # passed-in stuff takes precedence
2403 # if anything left - decompose rs_data
2405 if (keys %$rs_data) {
2406 push @$rs_data_vals, $rs_data->{$_}
2407 for sort keys %$rs_data;
2412 $guard = $rsrc->schema->storage->txn_scope_guard
2413 if $slices_with_rels;
2415 ### main source data
2416 # FIXME - need to switch entirely to a coderef-based thing,
2417 # so that large sets aren't copied several times... I think
2418 $rsrc->schema->storage->_insert_bulk(
2420 [ @$colnames, sort keys %$rs_data ],
2422 ref $data->[$_] eq 'ARRAY'
2424 $slices_with_rels ? [ @{$data->[$_]}[0..$#$colnames], @{$rs_data_vals||[]} ] # the collist changed
2425 : $rs_data_vals ? [ @{$data->[$_]}, @$rs_data_vals ]
2428 : [ @{$data->[$_]}{@$colnames}, @{$rs_data_vals||[]} ]
2429 } $data_start .. $#$data ],
2432 ### do the children relationships
2433 if ( $slices_with_rels ) {
2434 my @rels = grep { $colinfo->{$_}{is_rel} } keys %$colinfo
2435 or die 'wtf... please report a bug with DBIC_TRACE=1 output (stacktrace)';
2437 for my $sl (@$slices_with_rels) {
2439 my ($main_proto, $main_proto_rs);
2440 for my $rel (@rels) {
2441 next unless defined $sl->{$rel};
2445 (map { $_ => $sl->{$_} } @$colnames),
2448 unless (defined $colinfo->{$rel}{rs}) {
2450 $colinfo->{$rel}{rs} = $rsrc->related_source($rel)->resultset;
2452 $colinfo->{$rel}{fk_map} = { reverse %{ $rsrc->_resolve_relationship_condition(
2454 self_alias => "\xFE", # irrelevant
2455 foreign_alias => "\xFF", # irrelevant
2456 )->{identity_map} || {} } };
2460 $colinfo->{$rel}{rs}->search({ map # only so that we inherit them values properly, no actual search
2463 ( $main_proto_rs ||= $rsrc->resultset->search($main_proto) )
2464 ->get_column( $colinfo->{$rel}{fk_map}{$_} )
2468 keys %{$colinfo->{$rel}{fk_map}}
2469 })->populate( ref $sl->{$rel} eq 'ARRAY' ? $sl->{$rel} : [ $sl->{$rel} ] );
2476 $guard->commit if $guard;
2483 =item Arguments: none
2485 =item Return Value: L<$pager|Data::Page>
2489 Returns a L<Data::Page> object for the current resultset. Only makes
2490 sense for queries with a C<page> attribute.
2492 To get the full count of entries for a paged resultset, call
2493 C<total_entries> on the L<Data::Page> object.
2500 return $self->{pager} if $self->{pager};
2502 my $attrs = $self->{attrs};
2503 if (!defined $attrs->{page}) {
2504 $self->throw_exception("Can't create pager for non-paged rs");
2506 elsif ($attrs->{page} <= 0) {
2507 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2509 $attrs->{rows} ||= 10;
2511 # throw away the paging flags and re-run the count (possibly
2512 # with a subselect) to get the real total count
2513 my $count_attrs = { %$attrs };
2514 delete @{$count_attrs}{qw/rows offset page pager/};
2516 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2518 require DBIx::Class::ResultSet::Pager;
2519 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2520 sub { $total_rs->count }, #lazy-get the total
2522 $self->{attrs}{page},
2530 =item Arguments: $page_number
2532 =item Return Value: L<$resultset|/search>
2536 Returns a resultset for the $page_number page of the resultset on which page
2537 is called, where each page contains a number of rows equal to the 'rows'
2538 attribute set on the resultset (10 by default).
2543 my ($self, $page) = @_;
2544 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2551 =item Arguments: \%col_data
2553 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2557 Creates a new result object in the resultset's result class and returns
2558 it. The row is not inserted into the database at this point, call
2559 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2560 will tell you whether the result object has been inserted or not.
2562 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2567 my ($self, $values) = @_;
2569 $self->throw_exception( "Result object instantiation requires a single hashref argument" )
2570 if @_ > 2 or ref $values ne 'HASH';
2572 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2574 my $new = $self->result_class->new({
2576 ( @$cols_from_relations
2577 ? (-cols_from_relations => $cols_from_relations)
2580 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2584 reftype($new) eq 'HASH'
2590 carp_unique (sprintf (
2591 "%s->new returned a blessed empty hashref - a strong indicator something is wrong with its inheritance chain",
2592 $self->result_class,
2599 # _merge_with_rscond
2601 # Takes a simple hash of K/V data and returns its copy merged with the
2602 # condition already present on the resultset. Additionally returns an
2603 # arrayref of value/condition names, which were inferred from related
2604 # objects (this is needed for in-memory related objects)
2605 sub _merge_with_rscond {
2606 my ($self, $data) = @_;
2608 my ($implied_data, @cols_from_relations);
2610 my $alias = $self->{attrs}{alias};
2612 if (! defined $self->{cond}) {
2613 # just massage $data below
2615 elsif ($self->{cond} eq UNRESOLVABLE_CONDITION) {
2616 $implied_data = $self->{attrs}{related_objects}; # nothing might have been inserted yet
2617 @cols_from_relations = keys %{ $implied_data || {} };
2620 my $eqs = extract_equality_conditions( $self->{cond}, 'consider_nulls' );
2621 $implied_data = { map {
2622 ( ($eqs->{$_}||'') eq UNRESOLVABLE_CONDITION ) ? () : ( $_ => $eqs->{$_} )
2628 { %{ $self->_remove_alias($_, $alias) } }
2629 # precedence must be given to passed values over values inherited from
2630 # the cond, so the order here is important.
2631 ( $implied_data||(), $data)
2633 \@cols_from_relations
2637 # _has_resolved_attr
2639 # determines if the resultset defines at least one
2640 # of the attributes supplied
2642 # used to determine if a subquery is necessary
2644 # supports some virtual attributes:
2646 # This will scan for any joins being present on the resultset.
2647 # It is not a mere key-search but a deep inspection of {from}
2650 sub _has_resolved_attr {
2651 my ($self, @attr_names) = @_;
2653 my $attrs = $self->_resolved_attrs;
2657 for my $n (@attr_names) {
2658 if (grep { $n eq $_ } (qw/-join/) ) {
2659 $extra_checks{$n}++;
2663 my $attr = $attrs->{$n};
2665 next if not defined $attr;
2667 if (ref $attr eq 'HASH') {
2668 return 1 if keys %$attr;
2670 elsif (ref $attr eq 'ARRAY') {
2678 # a resolved join is expressed as a multi-level from
2680 $extra_checks{-join}
2682 ref $attrs->{from} eq 'ARRAY'
2684 @{$attrs->{from}} > 1
2692 # Remove the specified alias from the specified query hash. A copy is made so
2693 # the original query is not modified.
2696 my ($self, $query, $alias) = @_;
2698 my %orig = %{ $query || {} };
2701 foreach my $key (keys %orig) {
2703 $unaliased{$key} = $orig{$key};
2706 $unaliased{$1} = $orig{$key}
2707 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2717 =item Arguments: none
2719 =item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
2723 Returns the SQL query and bind vars associated with the invocant.
2725 This is generally used as the RHS for a subquery.
2732 my $attrs = { %{ $self->_resolved_attrs } };
2734 my $aq = $self->result_source->schema->storage->_select_args_to_query (
2735 $attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs
2745 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2747 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2751 my $artist = $schema->resultset('Artist')->find_or_new(
2752 { artist => 'fred' }, { key => 'artists' });
2754 $cd->cd_to_producer->find_or_new({ producer => $producer },
2755 { key => 'primary' });
2757 Find an existing record from this resultset using L</find>. if none exists,
2758 instantiate a new result object and return it. The object will not be saved
2759 into your storage until you call L<DBIx::Class::Row/insert> on it.
2761 You most likely want this method when looking for existing rows using a unique
2762 constraint that is not the primary key, or looking for related rows.
2764 If you want objects to be saved immediately, use L</find_or_create> instead.
2766 B<Note>: Make sure to read the documentation of L</find> and understand the
2767 significance of the C<key> attribute, as its lack may skew your search, and
2768 subsequently result in spurious new objects.
2770 B<Note>: Take care when using C<find_or_new> with a table having
2771 columns with default values that you intend to be automatically
2772 supplied by the database (e.g. an auto_increment primary key column).
2773 In normal usage, the value of such columns should NOT be included at
2774 all in the call to C<find_or_new>, even when set to C<undef>.
2780 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
2781 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2782 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2785 return $self->new_result($hash);
2792 =item Arguments: \%col_data
2794 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2798 Attempt to create a single new row or a row with multiple related rows
2799 in the table represented by the resultset (and related tables). This
2800 will not check for duplicate rows before inserting, use
2801 L</find_or_create> to do that.
2803 To create one row for this resultset, pass a hashref of key/value
2804 pairs representing the columns of the table and the values you wish to
2805 store. If the appropriate relationships are set up, foreign key fields
2806 can also be passed an object representing the foreign row, and the
2807 value will be set to its primary key.
2809 To create related objects, pass a hashref of related-object column values
2810 B<keyed on the relationship name>. If the relationship is of type C<multi>
2811 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2812 The process will correctly identify columns holding foreign keys, and will
2813 transparently populate them from the keys of the corresponding relation.
2814 This can be applied recursively, and will work correctly for a structure
2815 with an arbitrary depth and width, as long as the relationships actually
2816 exists and the correct column data has been supplied.
2818 Instead of hashrefs of plain related data (key/value pairs), you may
2819 also pass new or inserted objects. New objects (not inserted yet, see
2820 L</new_result>), will be inserted into their appropriate tables.
2822 Effectively a shortcut for C<< ->new_result(\%col_data)->insert >>.
2824 Example of creating a new row.
2826 $person_rs->create({
2827 name=>"Some Person",
2828 email=>"somebody@someplace.com"
2831 Example of creating a new row and also creating rows in a related C<has_many>
2832 or C<has_one> resultset. Note Arrayref.
2835 { artistid => 4, name => 'Manufactured Crap', cds => [
2836 { title => 'My First CD', year => 2006 },
2837 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2842 Example of creating a new row and also creating a row in a related
2843 C<belongs_to> resultset. Note Hashref.
2846 title=>"Music for Silly Walks",
2849 name=>"Silly Musician",
2857 When subclassing ResultSet never attempt to override this method. Since
2858 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2859 lot of the internals simply never call it, so your override will be
2860 bypassed more often than not. Override either L<DBIx::Class::Row/new>
2861 or L<DBIx::Class::Row/insert> depending on how early in the
2862 L</create> process you need to intervene. See also warning pertaining to
2869 sub create :DBIC_method_is_indirect_sugar {
2870 #my ($self, $col_data) = @_;
2871 DBIx::Class::_ENV_::ASSERT_NO_INTERNAL_INDIRECT_CALLS and fail_on_internal_call;
2872 return shift->new_result(shift)->insert;
2875 =head2 find_or_create
2879 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2881 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2885 $cd->cd_to_producer->find_or_create({ producer => $producer },
2886 { key => 'primary' });
2888 Tries to find a record based on its primary key or unique constraints; if none
2889 is found, creates one and returns that instead.
2891 my $cd = $schema->resultset('CD')->find_or_create({
2893 artist => 'Massive Attack',
2894 title => 'Mezzanine',
2898 Also takes an optional C<key> attribute, to search by a specific key or unique
2899 constraint. For example:
2901 my $cd = $schema->resultset('CD')->find_or_create(
2903 artist => 'Massive Attack',
2904 title => 'Mezzanine',
2906 { key => 'cd_artist_title' }
2909 B<Note>: Make sure to read the documentation of L</find> and understand the
2910 significance of the C<key> attribute, as its lack may skew your search, and
2911 subsequently result in spurious row creation.
2913 B<Note>: Because find_or_create() reads from the database and then
2914 possibly inserts based on the result, this method is subject to a race
2915 condition. Another process could create a record in the table after
2916 the find has completed and before the create has started. To avoid
2917 this problem, use find_or_create() inside a transaction.
2919 B<Note>: Take care when using C<find_or_create> with a table having
2920 columns with default values that you intend to be automatically
2921 supplied by the database (e.g. an auto_increment primary key column).
2922 In normal usage, the value of such columns should NOT be included at
2923 all in the call to C<find_or_create>, even when set to C<undef>.
2925 See also L</find> and L</update_or_create>. For information on how to declare
2926 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2928 If you need to know if an existing row was found or a new one created use
2929 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2930 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2933 my $cd = $schema->resultset('CD')->find_or_new({
2935 artist => 'Massive Attack',
2936 title => 'Mezzanine',
2940 if( !$cd->in_storage ) {
2947 sub find_or_create {
2949 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
2950 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2951 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2954 return $self->new_result($hash)->insert;
2957 =head2 update_or_create
2961 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
2963 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
2967 $resultset->update_or_create({ col => $val, ... });
2969 Like L</find_or_create>, but if a row is found it is immediately updated via
2970 C<< $found_row->update (\%col_data) >>.
2973 Takes an optional C<key> attribute to search on a specific unique constraint.
2976 # In your application
2977 my $cd = $schema->resultset('CD')->update_or_create(
2979 artist => 'Massive Attack',
2980 title => 'Mezzanine',
2983 { key => 'cd_artist_title' }
2986 $cd->cd_to_producer->update_or_create({
2987 producer => $producer,
2993 B<Note>: Make sure to read the documentation of L</find> and understand the
2994 significance of the C<key> attribute, as its lack may skew your search, and
2995 subsequently result in spurious row creation.
2997 B<Note>: Take care when using C<update_or_create> with a table having
2998 columns with default values that you intend to be automatically
2999 supplied by the database (e.g. an auto_increment primary key column).
3000 In normal usage, the value of such columns should NOT be included at
3001 all in the call to C<update_or_create>, even when set to C<undef>.
3003 See also L</find> and L</find_or_create>. For information on how to declare
3004 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
3006 If you need to know if an existing row was updated or a new one created use
3007 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
3008 to call L<DBIx::Class::Row/insert> to save the newly created row to the
3013 sub update_or_create {
3015 my $attrs = (@_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {});
3016 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3018 my $row = $self->find($cond, $attrs);
3020 $row->update($cond);
3024 return $self->new_result($cond)->insert;
3027 =head2 update_or_new
3031 =item Arguments: \%col_data, { key => $unique_constraint, L<%attrs|/ATTRIBUTES> }?
3033 =item Return Value: L<$result|DBIx::Class::Manual::ResultClass>
3037 $resultset->update_or_new({ col => $val, ... });
3039 Like L</find_or_new> but if a row is found it is immediately updated via
3040 C<< $found_row->update (\%col_data) >>.
3044 # In your application
3045 my $cd = $schema->resultset('CD')->update_or_new(
3047 artist => 'Massive Attack',
3048 title => 'Mezzanine',
3051 { key => 'cd_artist_title' }
3054 if ($cd->in_storage) {
3055 # the cd was updated
3058 # the cd is not yet in the database, let's insert it
3062 B<Note>: Make sure to read the documentation of L</find> and understand the
3063 significance of the C<key> attribute, as its lack may skew your search, and
3064 subsequently result in spurious new objects.
3066 B<Note>: Take care when using C<update_or_new> with a table having
3067 columns with default values that you intend to be automatically
3068 supplied by the database (e.g. an auto_increment primary key column).
3069 In normal usage, the value of such columns should NOT be included at
3070 all in the call to C<update_or_new>, even when set to C<undef>.
3072 See also L</find>, L</find_or_create> and L</find_or_new>.
3078 my $attrs = ( @_ > 1 && ref $_[-1] eq 'HASH' ? pop(@_) : {} );
3079 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
3081 my $row = $self->find( $cond, $attrs );
3082 if ( defined $row ) {
3083 $row->update($cond);
3087 return $self->new_result($cond);
3094 =item Arguments: none
3096 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass> | undef
3100 Gets the contents of the cache for the resultset, if the cache is set.
3102 The cache is populated either by using the L</prefetch> attribute to
3103 L</search> or by calling L</set_cache>.
3115 =item Arguments: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3117 =item Return Value: L<\@result_objs|DBIx::Class::Manual::ResultClass>
3121 Sets the contents of the cache for the resultset. Expects an arrayref
3122 of objects of the same class as those produced by the resultset. Note that
3123 if the cache is set, the resultset will return the cached objects rather
3124 than re-querying the database even if the cache attr is not set.
3126 The contents of the cache can also be populated by using the
3127 L</prefetch> attribute to L</search>.
3132 my ( $self, $data ) = @_;
3133 $self->throw_exception("set_cache requires an arrayref")
3134 if defined($data) && (ref $data ne 'ARRAY');
3135 $self->{all_cache} = $data;
3142 =item Arguments: none
3144 =item Return Value: undef
3148 Clears the cache for the resultset.
3153 shift->set_cache(undef);
3160 =item Arguments: none
3162 =item Return Value: true, if the resultset has been paginated
3170 return !!$self->{attrs}{page};
3177 =item Arguments: none
3179 =item Return Value: true, if the resultset has been ordered with C<order_by>.
3187 return scalar $self->result_source->schema->storage->_extract_order_criteria($self->{attrs}{order_by});
3190 =head2 related_resultset
3194 =item Arguments: $rel_name
3196 =item Return Value: L<$resultset|/search>
3200 Returns a related resultset for the supplied relationship name.
3202 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
3206 sub related_resultset {
3207 $_[0]->throw_exception(
3208 'Extra arguments to $rs->related_resultset() were always quietly '
3209 . 'discarded without consideration, you need to switch to '
3210 . '...->related_resultset( $relname )->search_rs( $search, $args ) instead.'
3213 return $_[0]->{related_resultsets}{$_[1]}
3214 if defined $_[0]->{related_resultsets}{$_[1]};
3216 my ($self, $rel) = @_;
3218 return $self->{related_resultsets}{$rel} = do {
3219 my $rsrc = $self->result_source;
3220 my $rel_info = $rsrc->relationship_info($rel);
3222 $self->throw_exception(
3223 "search_related: result source '" . $rsrc->source_name .
3224 "' has no such relationship $rel")
3227 my $attrs = $self->_chain_relationship($rel);
3229 my $storage = $rsrc->schema->storage;
3231 # Previously this atribute was deleted (instead of being set as it is now)
3232 # Doing so seems to be harmless in all available test permutations
3233 # See also 01d59a6a6 and mst's comment below
3235 $attrs->{alias} = $storage->relname_to_table_alias(
3237 $attrs->{seen_join}{$rel}
3240 # since this is search_related, and we already slid the select window inwards
3241 # (the select/as attrs were deleted in the beginning), we need to flip all
3242 # left joins to inner, so we get the expected results
3243 # read the comment on top of the actual function to see what this does
3244 $attrs->{from} = $storage->_inner_join_to_node( $attrs->{from}, $attrs->{alias} );
3246 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3247 delete $attrs->{result_class};
3251 # The reason we do this now instead of passing the alias to the
3252 # search_rs below is that if you wrap/overload resultset on the
3253 # source you need to know what alias it's -going- to have for things
3254 # to work sanely (e.g. RestrictWithObject wants to be able to add
3255 # extra query restrictions, and these may need to be $alias.)
3256 # -- mst ~ 2007 (01d59a6a6)
3258 # FIXME - this seems to be no longer neccessary (perhaps due to the
3259 # advances in relcond resolution. Testing DBIC::S::RWO and its only
3260 # dependent (as of Jun 2015 ) does not yield any difference with or
3261 # without this line. Nevertheless keep it as is for now, to minimize
3262 # churn, there is enough potential for breakage in 0.0829xx as it is
3263 # -- ribasushi Jun 2015
3265 my $rel_source = $rsrc->related_source($rel);
3266 local $rel_source->resultset_attributes->{alias} = $attrs->{alias};
3268 $rel_source->resultset->search_rs( undef, $attrs );
3271 if (my $cache = $self->get_cache) {
3272 my @related_cache = map
3273 { $_->related_resultset($rel)->get_cache || () }
3277 $new->set_cache([ map @$_, @related_cache ]) if @related_cache == @$cache;
3284 =head2 current_source_alias
3288 =item Arguments: none
3290 =item Return Value: $source_alias
3294 Returns the current table alias for the result source this resultset is built
3295 on, that will be used in the SQL query. Usually it is C<me>.
3297 Currently the source alias that refers to the result set returned by a
3298 L</search>/L</find> family method depends on how you got to the resultset: it's
3299 C<me> by default, but eg. L</search_related> aliases it to the related result
3300 source name (and keeps C<me> referring to the original result set). The long
3301 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3302 (and make this method unnecessary).
3304 Thus it's currently necessary to use this method in predefined queries (see
3305 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3306 source alias of the current result set:
3308 # in a result set class
3310 my ($self, $user) = @_;
3312 my $me = $self->current_source_alias;
3314 return $self->search({
3315 "$me.modified" => $user->id,
3319 The alias of L<newly created resultsets|/search> can be altered by the
3320 L<alias attribute|/alias>.
3324 sub current_source_alias {
3325 return (shift->{attrs} || {})->{alias} || 'me';
3328 =head2 as_subselect_rs
3332 =item Arguments: none
3334 =item Return Value: L<$resultset|/search>
3338 Act as a barrier to SQL symbols. The resultset provided will be made into a
3339 "virtual view" by including it as a subquery within the from clause. From this
3340 point on, any joined tables are inaccessible to ->search on the resultset (as if
3341 it were simply where-filtered without joins). For example:
3343 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3345 # 'x' now pollutes the query namespace
3347 # So the following works as expected
3348 my $ok_rs = $rs->search({'x.other' => 1});
3350 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3351 # def) we look for one row with contradictory terms and join in another table
3352 # (aliased 'x_2') which we never use
3353 my $broken_rs = $rs->search({'x.name' => 'def'});
3355 my $rs2 = $rs->as_subselect_rs;
3357 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3358 my $not_joined_rs = $rs2->search({'x.other' => 1});
3360 # works as expected: finds a 'table' row related to two x rows (abc and def)
3361 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3363 Another example of when one might use this would be to select a subset of
3364 columns in a group by clause:
3366 my $rs = $schema->resultset('Bar')->search(undef, {
3367 group_by => [qw{ id foo_id baz_id }],
3368 })->as_subselect_rs->search(undef, {
3369 columns => [qw{ id foo_id }]
3372 In the above example normally columns would have to be equal to the group by,
3373 but because we isolated the group by into a subselect the above works.
3377 sub as_subselect_rs {
3380 my $attrs = $self->_resolved_attrs;
3382 my $fresh_rs = (ref $self)->new (
3383 $self->result_source
3386 # these pieces will be locked in the subquery
3387 delete $fresh_rs->{cond};
3388 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3390 return $fresh_rs->search( {}, {
3392 $attrs->{alias} => $self->as_query,
3393 -alias => $attrs->{alias},
3394 -rsrc => $self->result_source,
3396 alias => $attrs->{alias},
3400 # This code is called by search_related, and makes sure there
3401 # is clear separation between the joins before, during, and
3402 # after the relationship. This information is needed later
3403 # in order to properly resolve prefetch aliases (any alias
3404 # with a relation_chain_depth less than the depth of the
3405 # current prefetch is not considered)
3407 # The increments happen twice per join. An even number means a
3408 # relationship specified via a search_related, whereas an odd
3409 # number indicates a join/prefetch added via attributes
3411 # Also this code will wrap the current resultset (the one we
3412 # chain to) in a subselect IFF it contains limiting attributes
3413 sub _chain_relationship {
3414 my ($self, $rel) = @_;
3415 my $source = $self->result_source;
3416 my $attrs = { %{$self->{attrs}||{}} };
3418 # we need to take the prefetch the attrs into account before we
3419 # ->_resolve_join as otherwise they get lost - captainL
3420 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3422 delete @{$attrs}{qw/join prefetch collapse group_by distinct _grouped_by_distinct select as columns +select +as +columns/};
3424 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3427 my @force_subq_attrs = qw/offset rows group_by having/;
3430 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3432 $self->_has_resolved_attr (@force_subq_attrs)
3434 # Nuke the prefetch (if any) before the new $rs attrs
3435 # are resolved (prefetch is useless - we are wrapping
3436 # a subquery anyway).
3437 my $rs_copy = $self->search;
3438 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3439 $rs_copy->{attrs}{join},
3440 delete $rs_copy->{attrs}{prefetch},
3445 -alias => $attrs->{alias},
3446 $attrs->{alias} => $rs_copy->as_query,
3448 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3449 $seen->{-relation_chain_depth} = 0;
3451 elsif ($attrs->{from}) { #shallow copy suffices
3452 $from = [ @{$attrs->{from}} ];
3457 -alias => $attrs->{alias},
3458 $attrs->{alias} => $source->from,
3462 my $jpath = ($seen->{-relation_chain_depth})
3463 ? $from->[-1][0]{-join_path}
3466 my @requested_joins = $source->_resolve_join(
3473 push @$from, @requested_joins;
3475 $seen->{-relation_chain_depth}++;
3477 # if $self already had a join/prefetch specified on it, the requested
3478 # $rel might very well be already included. What we do in this case
3479 # is effectively a no-op (except that we bump up the chain_depth on
3480 # the join in question so we could tell it *is* the search_related)
3483 # we consider the last one thus reverse
3484 for my $j (reverse @requested_joins) {
3485 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3486 if ($rel eq $last_j) {
3487 $j->[0]{-relation_chain_depth}++;
3493 unless ($already_joined) {
3494 push @$from, $source->_resolve_join(
3502 $seen->{-relation_chain_depth}++;
3504 return {%$attrs, from => $from, seen_join => $seen};
3507 sub _resolved_attrs {
3509 return $self->{_attrs} if $self->{_attrs};
3511 my $attrs = { %{ $self->{attrs} || {} } };
3512 my $source = $attrs->{result_source} = $self->result_source;
3513 my $alias = $attrs->{alias};
3515 $self->throw_exception("Specifying distinct => 1 in conjunction with collapse => 1 is unsupported")
3516 if $attrs->{collapse} and $attrs->{distinct};
3519 # Sanity check the paging attributes
3520 # SQLMaker does it too, but in case of a software_limit we'll never get there
3521 if (defined $attrs->{offset}) {
3522 $self->throw_exception('A supplied offset attribute must be a non-negative integer')
3523 if ( $attrs->{offset} =~ /[^0-9]/ or $attrs->{offset} < 0 );
3525 if (defined $attrs->{rows}) {
3526 $self->throw_exception("The rows attribute must be a positive integer if present")
3527 if ( $attrs->{rows} =~ /[^0-9]/ or $attrs->{rows} <= 0 );
3530 # normalize where condition
3531 $attrs->{where} = normalize_sqla_condition( $attrs->{where} )
3534 # default selection list
3535 $attrs->{columns} = [ $source->columns ]
3536 unless grep { exists $attrs->{$_} } qw/columns cols select as/;
3538 # merge selectors together
3539 for (qw/columns select as/) {
3540 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3541 if $attrs->{$_} or $attrs->{"+$_"};
3544 # disassemble columns
3546 if (my $cols = delete $attrs->{columns}) {
3547 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3548 if (ref $c eq 'HASH') {
3549 for my $as (sort keys %$c) {
3550 push @sel, $c->{$as};
3561 # when trying to weed off duplicates later do not go past this point -
3562 # everything added from here on is unbalanced "anyone's guess" stuff
3563 my $dedup_stop_idx = $#as;
3565 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3567 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3568 if $attrs->{select};
3570 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3571 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
3573 # disqualify all $alias.col as-bits (inflate-map mandated)
3574 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
3576 # de-duplicate the result (remove *identical* select/as pairs)
3577 # and also die on duplicate {as} pointing to different {select}s
3578 # not using a c-style for as the condition is prone to shrinkage
3581 while ($i <= $dedup_stop_idx) {
3582 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3587 elsif ($seen->{$as[$i]}++) {
3588 $self->throw_exception(
3589 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3597 $attrs->{select} = \@sel;
3598 $attrs->{as} = \@as;
3600 $attrs->{from} ||= [{
3602 -alias => $self->{attrs}{alias},
3603 $self->{attrs}{alias} => $source->from,
3606 if ( $attrs->{join} || $attrs->{prefetch} ) {
3608 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3609 if ref $attrs->{from} ne 'ARRAY';
3611 my $join = (delete $attrs->{join}) || {};
3613 if ( defined $attrs->{prefetch} ) {
3614 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3617 $attrs->{from} = # have to copy here to avoid corrupting the original
3619 @{ $attrs->{from} },
3620 $source->_resolve_join(
3623 { %{ $attrs->{seen_join} || {} } },
3624 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3625 ? $attrs->{from}[-1][0]{-join_path}
3633 for my $attr (qw(order_by group_by)) {
3635 if ( defined $attrs->{$attr} ) {
3637 ref( $attrs->{$attr} ) eq 'ARRAY'
3638 ? [ @{ $attrs->{$attr} } ]
3639 : [ $attrs->{$attr} || () ]
3642 delete $attrs->{$attr} unless @{$attrs->{$attr}};
3647 # set collapse default based on presence of prefetch
3650 defined $attrs->{prefetch}
3652 $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
3654 $self->throw_exception("Specifying prefetch in conjunction with an explicit collapse => 0 is unsupported")
3655 if defined $attrs->{collapse} and ! $attrs->{collapse};
3657 $attrs->{collapse} = 1;
3661 # run through the resulting joinstructure (starting from our current slot)
3662 # and unset collapse if proven unnecessary
3664 # also while we are at it find out if the current root source has
3665 # been premultiplied by previous related_source chaining
3667 # this allows to predict whether a root object with all other relation
3668 # data set to NULL is in fact unique
3669 if ($attrs->{collapse}) {
3671 if (ref $attrs->{from} eq 'ARRAY') {
3673 if (@{$attrs->{from}} == 1) {
3674 # no joins - no collapse
3675 $attrs->{collapse} = 0;
3678 # find where our table-spec starts
3679 my @fromlist = @{$attrs->{from}};
3681 my $t = shift @fromlist;
3684 # me vs join from-spec distinction - a ref means non-root
3685 if (ref $t eq 'ARRAY') {
3687 $is_multi ||= ! $t->{-is_single};
3689 last if ($t->{-alias} && $t->{-alias} eq $alias);
3690 $attrs->{_main_source_premultiplied} ||= $is_multi;
3693 # no non-singles remaining, nor any premultiplication - nothing to collapse
3695 ! $attrs->{_main_source_premultiplied}
3697 ! grep { ! $_->[0]{-is_single} } @fromlist
3699 $attrs->{collapse} = 0;
3705 # if we can not analyze the from - err on the side of safety
3706 $attrs->{_main_source_premultiplied} = 1;
3711 # generate the distinct induced group_by before injecting the prefetched select/as parts
3712 if (delete $attrs->{distinct}) {
3713 if ($attrs->{group_by}) {
3714 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3717 $attrs->{_grouped_by_distinct} = 1;
3718 # distinct affects only the main selection part, not what prefetch may add below
3719 ($attrs->{group_by}, my $new_order) = $source->schema->storage->_group_over_selection($attrs);
3721 # FIXME possibly ignore a rewritten order_by (may turn out to be an issue)
3722 # The thinking is: if we are collapsing the subquerying prefetch engine will
3723 # rip stuff apart for us anyway, and we do not want to have a potentially
3724 # function-converted external order_by
3725 # ( there is an explicit if ( collapse && _grouped_by_distinct ) check in DBIHacks )
3726 $attrs->{order_by} = $new_order unless $attrs->{collapse};
3731 # generate selections based on the prefetch helper
3734 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3735 if $attrs->{_dark_selector};
3737 # this is a separate structure (we don't look in {from} directly)
3738 # as the resolver needs to shift things off the lists to work
3739 # properly (identical-prefetches on different branches)
3740 my $joined_node_aliases_map = {};
3741 if (ref $attrs->{from} eq 'ARRAY') {
3743 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3745 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3746 next unless $j->[0]{-alias};
3747 next unless $j->[0]{-join_path};
3748 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3750 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3752 my $p = $joined_node_aliases_map;
3753 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3754 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3758 ( push @{$attrs->{select}}, $_->[0] ) and ( push @{$attrs->{as}}, $_->[1] )
3759 for $source->_resolve_selection_from_prefetch( $prefetch, $joined_node_aliases_map );
3763 $attrs->{_simple_passthrough_construction} = !(
3766 grep { $_ =~ /\./ } @{$attrs->{as}}
3770 # if both page and offset are specified, produce a combined offset
3771 # even though it doesn't make much sense, this is what pre 081xx has
3773 if (my $page = delete $attrs->{page}) {
3775 ($attrs->{rows} * ($page - 1))
3777 ($attrs->{offset} || 0)
3781 return $self->{_attrs} = $attrs;
3785 my ($self, $attr) = @_;
3787 if (ref $attr eq 'HASH') {
3788 return $self->_rollout_hash($attr);
3789 } elsif (ref $attr eq 'ARRAY') {
3790 return $self->_rollout_array($attr);
3796 sub _rollout_array {
3797 my ($self, $attr) = @_;
3800 foreach my $element (@{$attr}) {
3801 if (ref $element eq 'HASH') {
3802 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3803 } elsif (ref $element eq 'ARRAY') {
3804 # XXX - should probably recurse here
3805 push( @rolled_array, @{$self->_rollout_array($element)} );
3807 push( @rolled_array, $element );
3810 return \@rolled_array;
3814 my ($self, $attr) = @_;
3817 foreach my $key (keys %{$attr}) {
3818 push( @rolled_array, { $key => $attr->{$key} } );
3820 return \@rolled_array;
3823 sub _calculate_score {
3824 my ($self, $a, $b) = @_;
3826 if (defined $a xor defined $b) {
3829 elsif (not defined $a) {
3833 if (ref $b eq 'HASH') {
3834 my ($b_key) = keys %{$b};
3835 $b_key = '' if ! defined $b_key;
3836 if (ref $a eq 'HASH') {
3837 my ($a_key) = keys %{$a};
3838 $a_key = '' if ! defined $a_key;
3839 if ($a_key eq $b_key) {
3840 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3845 return ($a eq $b_key) ? 1 : 0;
3848 if (ref $a eq 'HASH') {
3849 my ($a_key) = keys %{$a};
3850 return ($b eq $a_key) ? 1 : 0;
3852 return ($b eq $a) ? 1 : 0;
3857 sub _merge_joinpref_attr {
3858 my ($self, $orig, $import) = @_;
3860 return $import unless defined($orig);
3861 return $orig unless defined($import);
3863 $orig = $self->_rollout_attr($orig);
3864 $import = $self->_rollout_attr($import);
3867 foreach my $import_element ( @{$import} ) {
3868 # find best candidate from $orig to merge $b_element into
3869 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3870 foreach my $orig_element ( @{$orig} ) {
3871 my $score = $self->_calculate_score( $orig_element, $import_element );
3872 if ($score > $best_candidate->{score}) {
3873 $best_candidate->{position} = $position;
3874 $best_candidate->{score} = $score;
3878 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3879 $import_key = '' if not defined $import_key;
3881 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3882 push( @{$orig}, $import_element );
3884 my $orig_best = $orig->[$best_candidate->{position}];
3885 # merge orig_best and b_element together and replace original with merged
3886 if (ref $orig_best ne 'HASH') {
3887 $orig->[$best_candidate->{position}] = $import_element;
3888 } elsif (ref $import_element eq 'HASH') {
3889 my ($key) = keys %{$orig_best};
3890 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3893 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3896 return @$orig ? $orig : ();
3904 require Hash::Merge;
3905 my $hm = Hash::Merge->new;
3907 $hm->specify_behavior({
3910 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3912 if ($defl xor $defr) {
3913 return [ $defl ? $_[0] : $_[1] ];
3918 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3922 return [$_[0], $_[1]];
3926 return $_[1] if !defined $_[0];
3927 return $_[1] if __HM_DEDUP and grep { $_ eq $_[0] } @{$_[1]};
3928 return [$_[0], @{$_[1]}]
3931 return [] if !defined $_[0] and !keys %{$_[1]};
3932 return [ $_[1] ] if !defined $_[0];
3933 return [ $_[0] ] if !keys %{$_[1]};
3934 return [$_[0], $_[1]]
3939 return $_[0] if !defined $_[1];
3940 return $_[0] if __HM_DEDUP and grep { $_ eq $_[1] } @{$_[0]};
3941 return [@{$_[0]}, $_[1]]
3944 my @ret = @{$_[0]} or return $_[1];
3945 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3946 my %idx = map { $_ => 1 } @ret;
3947 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3951 return [ $_[1] ] if ! @{$_[0]};
3952 return $_[0] if !keys %{$_[1]};
3953 return $_[0] if __HM_DEDUP and grep { $_ eq $_[1] } @{$_[0]};
3954 return [ @{$_[0]}, $_[1] ];
3959 return [] if !keys %{$_[0]} and !defined $_[1];
3960 return [ $_[0] ] if !defined $_[1];
3961 return [ $_[1] ] if !keys %{$_[0]};
3962 return [$_[0], $_[1]]
3965 return [] if !keys %{$_[0]} and !@{$_[1]};
3966 return [ $_[0] ] if !@{$_[1]};
3967 return $_[1] if !keys %{$_[0]};
3968 return $_[1] if __HM_DEDUP and grep { $_ eq $_[0] } @{$_[1]};
3969 return [ $_[0], @{$_[1]} ];
3972 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3973 return [ $_[0] ] if !keys %{$_[1]};
3974 return [ $_[1] ] if !keys %{$_[0]};
3975 return [ $_[0] ] if $_[0] eq $_[1];
3976 return [ $_[0], $_[1] ];
3979 } => 'DBIC_RS_ATTR_MERGER');
3983 return $hm->merge ($_[1], $_[2]);
3987 sub STORABLE_freeze {
3988 my ($self, $cloning) = @_;
3989 my $to_serialize = { %$self };
3991 # A cursor in progress can't be serialized (and would make little sense anyway)
3992 # the parser can be regenerated (and can't be serialized)
3993 delete @{$to_serialize}{qw/cursor _row_parser _result_inflator/};
3995 # nor is it sensical to store a not-yet-fired-count pager
3996 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3997 delete $to_serialize->{pager};
4000 Storable::nfreeze($to_serialize);
4003 # need this hook for symmetry
4005 my ($self, $cloning, $serialized) = @_;
4007 %$self = %{ Storable::thaw($serialized) };
4013 =head2 throw_exception
4015 See L<DBIx::Class::Schema/throw_exception> for details.
4019 sub throw_exception {
4022 if (ref $self and my $rsrc = $self->result_source) {
4023 $rsrc->throw_exception(@_)
4026 DBIx::Class::Exception->throw(@_);
4034 # XXX: FIXME: Attributes docs need clearing up
4038 Attributes are used to refine a ResultSet in various ways when
4039 searching for data. They can be passed to any method which takes an
4040 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
4043 Default attributes can be set on the result class using
4044 L<DBIx::Class::ResultSource/resultset_attributes>. (Please read
4045 the CAVEATS on that feature before using it!)
4047 These are in no particular order:
4053 =item Value: ( $order_by | \@order_by | \%order_by )
4057 Which column(s) to order the results by.
4059 [The full list of suitable values is documented in
4060 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
4063 If a single column name, or an arrayref of names is supplied, the
4064 argument is passed through directly to SQL. The hashref syntax allows
4065 for connection-agnostic specification of ordering direction:
4067 For descending order:
4069 order_by => { -desc => [qw/col1 col2 col3/] }
4071 For explicit ascending order:
4073 order_by => { -asc => 'col' }
4075 The old scalarref syntax (i.e. order_by => \'year DESC') is still
4076 supported, although you are strongly encouraged to use the hashref
4077 syntax as outlined above.
4083 =item Value: \@columns | \%columns | $column
4087 Shortcut to request a particular set of columns to be retrieved. Each
4088 column spec may be a string (a table column name), or a hash (in which
4089 case the key is the C<as> value, and the value is used as the C<select>
4090 expression). Adds the L</current_source_alias> onto the start of any column without a C<.> in
4091 it and sets C<select> from that, then auto-populates C<as> from
4092 C<select> as normal. (You may also use the C<cols> attribute, as in
4093 earlier versions of DBIC, but this is deprecated)
4095 Essentially C<columns> does the same as L</select> and L</as>.
4097 columns => [ 'some_column', { dbic_slot => 'another_column' } ]
4101 select => [qw(some_column another_column)],
4102 as => [qw(some_column dbic_slot)]
4104 If you want to individually retrieve related columns (in essence perform
4105 manual L</prefetch>) you have to make sure to specify the correct inflation slot
4106 chain such that it matches existing relationships:
4108 my $rs = $schema->resultset('Artist')->search({}, {
4109 # required to tell DBIC to collapse has_many relationships
4111 join => { cds => 'tracks' },
4113 'cds.cdid' => 'cds.cdid',
4114 'cds.tracks.title' => 'tracks.title',
4118 Like elsewhere, literal SQL or literal values can be included by using a
4119 scalar reference or a literal bind value, and these values will be available
4120 in the result with C<get_column> (see also
4121 L<SQL::Abstract/Literal SQL and value type operators>):
4123 # equivalent SQL: SELECT 1, 'a string', IF(my_column,?,?) ...
4124 # bind values: $true_value, $false_value
4128 bar => \q{'a string'},
4129 baz => \[ 'IF(my_column,?,?)', $true_value, $false_value ],
4135 B<NOTE:> You B<MUST> explicitly quote C<'+columns'> when using this attribute.
4136 Not doing so causes Perl to incorrectly interpret C<+columns> as a bareword
4137 with a unary plus operator before it, which is the same as simply C<columns>.
4141 =item Value: \@extra_columns
4145 Indicates additional columns to be selected from storage. Works the same as
4146 L</columns> but adds columns to the current selection. (You may also use the
4147 C<include_columns> attribute, as in earlier versions of DBIC, but this is
4150 $schema->resultset('CD')->search(undef, {
4151 '+columns' => ['artist.name'],
4155 would return all CDs and include a 'name' column to the information
4156 passed to object inflation. Note that the 'artist' is the name of the
4157 column (or relationship) accessor, and 'name' is the name of the column
4158 accessor in the related table.
4164 =item Value: \@select_columns
4168 Indicates which columns should be selected from the storage. You can use
4169 column names, or in the case of RDBMS back ends, function or stored procedure
4172 $rs = $schema->resultset('Employee')->search(undef, {
4175 { count => 'employeeid' },
4176 { max => { length => 'name' }, -as => 'longest_name' }
4181 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
4183 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
4184 use L</select>, to instruct DBIx::Class how to store the result of the column.
4186 Also note that the L</as> attribute has B<nothing to do> with the SQL-side
4187 C<AS> identifier aliasing. You B<can> alias a function (so you can use it e.g.
4188 in an C<ORDER BY> clause), however this is done via the C<-as> B<select
4189 function attribute> supplied as shown in the example above.
4193 B<NOTE:> You B<MUST> explicitly quote C<'+select'> when using this attribute.
4194 Not doing so causes Perl to incorrectly interpret C<+select> as a bareword
4195 with a unary plus operator before it, which is the same as simply C<select>.
4199 =item Value: \@extra_select_columns
4203 Indicates additional columns to be selected from storage. Works the same as
4204 L</select> but adds columns to the current selection, instead of specifying
4205 a new explicit list.
4211 =item Value: \@inflation_names
4215 Indicates DBIC-side names for object inflation. That is L</as> indicates the
4216 slot name in which the column value will be stored within the
4217 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
4218 identifier by the C<get_column> method (or via the object accessor B<if one
4219 with the same name already exists>) as shown below.
4221 The L</as> attribute has B<nothing to do> with the SQL-side identifier
4222 aliasing C<AS>. See L</select> for details.
4224 $rs = $schema->resultset('Employee')->search(undef, {
4227 { count => 'employeeid' },
4228 { max => { length => 'name' }, -as => 'longest_name' }
4237 If the object against which the search is performed already has an accessor
4238 matching a column name specified in C<as>, the value can be retrieved using
4239 the accessor as normal:
4241 my $name = $employee->name();
4243 If on the other hand an accessor does not exist in the object, you need to
4244 use C<get_column> instead:
4246 my $employee_count = $employee->get_column('employee_count');
4248 You can create your own accessors if required - see
4249 L<DBIx::Class::Manual::Cookbook> for details.
4253 B<NOTE:> You B<MUST> explicitly quote C<'+as'> when using this attribute.
4254 Not doing so causes Perl to incorrectly interpret C<+as> as a bareword
4255 with a unary plus operator before it, which is the same as simply C<as>.
4259 =item Value: \@extra_inflation_names
4263 Indicates additional inflation names for selectors added via L</+select>. See L</as>.
4269 =item Value: ($rel_name | \@rel_names | \%rel_names)
4273 Contains a list of relationships that should be joined for this query. For
4276 # Get CDs by Nine Inch Nails
4277 my $rs = $schema->resultset('CD')->search(
4278 { 'artist.name' => 'Nine Inch Nails' },
4279 { join => 'artist' }
4282 Can also contain a hash reference to refer to the other relation's relations.
4285 package MyApp::Schema::Track;
4286 use base qw/DBIx::Class/;
4287 __PACKAGE__->table('track');
4288 __PACKAGE__->add_columns(qw/trackid cd position title/);
4289 __PACKAGE__->set_primary_key('trackid');
4290 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
4293 # In your application
4294 my $rs = $schema->resultset('Artist')->search(
4295 { 'track.title' => 'Teardrop' },
4297 join => { cd => 'track' },
4298 order_by => 'artist.name',
4302 You need to use the relationship (not the table) name in conditions,
4303 because they are aliased as such. The current table is aliased as "me", so
4304 you need to use me.column_name in order to avoid ambiguity. For example:
4306 # Get CDs from 1984 with a 'Foo' track
4307 my $rs = $schema->resultset('CD')->search(
4310 'tracks.name' => 'Foo'
4312 { join => 'tracks' }
4315 If the same join is supplied twice, it will be aliased to <rel>_2 (and
4316 similarly for a third time). For e.g.
4318 my $rs = $schema->resultset('Artist')->search({
4319 'cds.title' => 'Down to Earth',
4320 'cds_2.title' => 'Popular',
4322 join => [ qw/cds cds/ ],
4325 will return a set of all artists that have both a cd with title 'Down
4326 to Earth' and a cd with title 'Popular'.
4328 If you want to fetch related objects from other tables as well, see L</prefetch>
4331 NOTE: An internal join-chain pruner will discard certain joins while
4332 constructing the actual SQL query, as long as the joins in question do not
4333 affect the retrieved result. This for example includes 1:1 left joins
4334 that are not part of the restriction specification (WHERE/HAVING) nor are
4335 a part of the query selection.
4337 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4343 =item Value: (0 | 1)
4347 When set to a true value, indicates that any rows fetched from joined has_many
4348 relationships are to be aggregated into the corresponding "parent" object. For
4349 example, the resultset:
4351 my $rs = $schema->resultset('CD')->search({}, {
4352 '+columns' => [ qw/ tracks.title tracks.position / ],
4357 While executing the following query:
4359 SELECT me.*, tracks.title, tracks.position
4361 LEFT JOIN track tracks
4362 ON tracks.cdid = me.cdid
4364 Will return only as many objects as there are rows in the CD source, even
4365 though the result of the query may span many rows. Each of these CD objects
4366 will in turn have multiple "Track" objects hidden behind the has_many
4367 generated accessor C<tracks>. Without C<< collapse => 1 >>, the return values
4368 of this resultset would be as many CD objects as there are tracks (a "Cartesian
4369 product"), with each CD object containing exactly one of all fetched Track data.
4371 When a collapse is requested on a non-ordered resultset, an order by some
4372 unique part of the main source (the left-most table) is inserted automatically.
4373 This is done so that the resultset is allowed to be "lazy" - calling
4374 L<< $rs->next|/next >> will fetch only as many rows as it needs to build the next
4375 object with all of its related data.
4377 If an L</order_by> is already declared, and orders the resultset in a way that
4378 makes collapsing as described above impossible (e.g. C<< ORDER BY
4379 has_many_rel.column >> or C<ORDER BY RANDOM()>), DBIC will automatically
4380 switch to "eager" mode and slurp the entire resultset before constructing the
4381 first object returned by L</next>.
4383 Setting this attribute on a resultset that does not join any has_many
4384 relations is a no-op.
4386 For a more in-depth discussion, see L</PREFETCHING>.
4392 =item Value: ($rel_name | \@rel_names | \%rel_names)
4396 This attribute is a shorthand for specifying a L</join> spec, adding all
4397 columns from the joined related sources as L</+columns> and setting
4398 L</collapse> to a true value. It can be thought of as a rough B<superset>
4399 of the L</join> attribute.
4401 For example, the following two queries are equivalent:
4403 my $rs = $schema->resultset('Artist')->search({}, {
4404 prefetch => { cds => ['genre', 'tracks' ] },
4409 my $rs = $schema->resultset('Artist')->search({}, {
4410 join => { cds => ['genre', 'tracks' ] },
4414 { +{ "cds.$_" => "cds.$_" } }
4415 $schema->source('Artist')->related_source('cds')->columns
4418 { +{ "cds.genre.$_" => "genre.$_" } }
4419 $schema->source('Artist')->related_source('cds')->related_source('genre')->columns
4422 { +{ "cds.tracks.$_" => "tracks.$_" } }
4423 $schema->source('Artist')->related_source('cds')->related_source('tracks')->columns
4428 Both producing the following SQL:
4430 SELECT me.artistid, me.name, me.rank, me.charfield,
4431 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track,
4432 genre.genreid, genre.name,
4433 tracks.trackid, tracks.cd, tracks.position, tracks.title, tracks.last_updated_on, tracks.last_updated_at
4436 ON cds.artist = me.artistid
4437 LEFT JOIN genre genre
4438 ON genre.genreid = cds.genreid
4439 LEFT JOIN track tracks
4440 ON tracks.cd = cds.cdid
4441 ORDER BY me.artistid
4443 While L</prefetch> implies a L</join>, it is ok to mix the two together, as
4444 the arguments are properly merged and generally do the right thing. For
4445 example, you may want to do the following:
4447 my $artists_and_cds_without_genre = $schema->resultset('Artist')->search(
4448 { 'genre.genreid' => undef },
4450 join => { cds => 'genre' },
4455 Which generates the following SQL:
4457 SELECT me.artistid, me.name, me.rank, me.charfield,
4458 cds.cdid, cds.artist, cds.title, cds.year, cds.genreid, cds.single_track
4461 ON cds.artist = me.artistid
4462 LEFT JOIN genre genre
4463 ON genre.genreid = cds.genreid
4464 WHERE genre.genreid IS NULL
4465 ORDER BY me.artistid
4467 For a more in-depth discussion, see L</PREFETCHING>.
4473 =item Value: $source_alias
4477 Sets the source alias for the query. Normally, this defaults to C<me>, but
4478 nested search queries (sub-SELECTs) might need specific aliases set to
4479 reference inner queries. For example:
4482 ->related_resultset('CDs')
4483 ->related_resultset('Tracks')
4485 'track.id' => { -ident => 'none_search.id' },
4489 my $ids = $self->search({
4492 alias => 'none_search',
4493 group_by => 'none_search.id',
4494 })->get_column('id')->as_query;
4496 $self->search({ id => { -in => $ids } })
4498 This attribute is directly tied to L</current_source_alias>.
4508 Makes the resultset paged and specifies the page to retrieve. Effectively
4509 identical to creating a non-pages resultset and then calling ->page($page)
4512 If L</rows> attribute is not specified it defaults to 10 rows per page.
4514 When you have a paged resultset, L</count> will only return the number
4515 of rows in the page. To get the total, use the L</pager> and call
4516 C<total_entries> on it.
4526 Specifies the maximum number of rows for direct retrieval or the number of
4527 rows per page if the page attribute or method is used.
4533 =item Value: $offset
4537 Specifies the (zero-based) row number for the first row to be returned, or the
4538 of the first row of the first page if paging is used.
4540 =head2 software_limit
4544 =item Value: (0 | 1)
4548 When combined with L</rows> and/or L</offset> the generated SQL will not
4549 include any limit dialect stanzas. Instead the entire result will be selected
4550 as if no limits were specified, and DBIC will perform the limit locally, by
4551 artificially advancing and finishing the resulting L</cursor>.
4553 This is the recommended way of performing resultset limiting when no sane RDBMS
4554 implementation is available (e.g.
4555 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4556 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4562 =item Value: \@columns
4566 A arrayref of columns to group by. Can include columns of joined tables.
4568 group_by => [qw/ column1 column2 ... /]
4574 =item Value: $condition
4578 The HAVING operator specifies a B<secondary> condition applied to the set
4579 after the grouping calculations have been done. In other words it is a
4580 constraint just like L</where> (and accepting the same
4581 L<SQL::Abstract syntax|SQL::Abstract/WHERE CLAUSES>) applied to the data
4582 as it exists after GROUP BY has taken place. Specifying L</having> without
4583 L</group_by> is a logical mistake, and a fatal error on most RDBMS engines.
4587 having => { 'count_employee' => { '>=', 100 } }
4589 or with an in-place function in which case literal SQL is required:
4591 having => \[ 'count(employee) >= ?', 100 ]
4597 =item Value: (0 | 1)
4601 Set to 1 to automatically generate a L</group_by> clause based on the selection
4602 (including intelligent handling of L</order_by> contents). Note that the group
4603 criteria calculation takes place over the B<final> selection. This includes
4604 any L</+columns>, L</+select> or L</order_by> additions in subsequent
4605 L</search> calls, and standalone columns selected via
4606 L<DBIx::Class::ResultSetColumn> (L</get_column>). A notable exception are the
4607 extra selections specified via L</prefetch> - such selections are explicitly
4608 excluded from group criteria calculations.
4610 If the final ResultSet also explicitly defines a L</group_by> attribute, this
4611 setting is ignored and an appropriate warning is issued.
4615 Adds extra conditions to the resultset, combined with the preexisting C<WHERE>
4616 conditions, same as the B<first> argument to the L<search operator|/search>
4618 # only return rows WHERE deleted IS NULL for all searches
4619 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4621 Note that the above example is
4622 L<strongly discouraged|DBIx::Class::ResultSource/resultset_attributes>.
4626 Set to 1 to cache search results. This prevents extra SQL queries if you
4627 revisit rows in your ResultSet:
4629 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4631 while( my $artist = $resultset->next ) {
4635 $resultset->first; # without cache, this would issue a query
4637 By default, searches are not cached.
4639 For more examples of using these attributes, see
4640 L<DBIx::Class::Manual::Cookbook>.
4646 =item Value: ( 'update' | 'shared' | \$scalar )
4650 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4651 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4656 DBIx::Class supports arbitrary related data prefetching from multiple related
4657 sources. Any combination of relationship types and column sets are supported.
4658 If L<collapsing|/collapse> is requested, there is an additional requirement of
4659 selecting enough data to make every individual object uniquely identifiable.
4661 Here are some more involved examples, based on the following relationship map:
4664 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4665 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4666 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4668 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4670 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4674 my $rs = $schema->resultset('Tag')->search(
4683 The initial search results in SQL like the following:
4685 SELECT tag.*, cd.*, artist.* FROM tag
4686 JOIN cd ON tag.cd = cd.cdid
4687 JOIN artist ON cd.artist = artist.artistid
4689 L<DBIx::Class> has no need to go back to the database when we access the
4690 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4693 Simple prefetches will be joined automatically, so there is no need
4694 for a C<join> attribute in the above search.
4696 The L</prefetch> attribute can be used with any of the relationship types
4697 and multiple prefetches can be specified together. Below is a more complex
4698 example that prefetches a CD's artist, its liner notes (if present),
4699 the cover image, the tracks on that CD, and the guests on those
4702 my $rs = $schema->resultset('CD')->search(
4706 { artist => 'record_label'}, # belongs_to => belongs_to
4707 'liner_note', # might_have
4708 'cover_image', # has_one
4709 { tracks => 'guests' }, # has_many => has_many
4714 This will produce SQL like the following:
4716 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4720 ON artist.artistid = me.artistid
4721 JOIN record_label record_label
4722 ON record_label.labelid = artist.labelid
4723 LEFT JOIN track tracks
4724 ON tracks.cdid = me.cdid
4725 LEFT JOIN guest guests
4726 ON guests.trackid = track.trackid
4727 LEFT JOIN liner_notes liner_note
4728 ON liner_note.cdid = me.cdid
4729 JOIN cd_artwork cover_image
4730 ON cover_image.cdid = me.cdid
4733 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4734 C<tracks>, and C<guests> of the CD will all be available through the
4735 relationship accessors without the need for additional queries to the
4740 Prefetch does a lot of deep magic. As such, it may not behave exactly
4741 as you might expect.
4747 Prefetch uses the L</cache> to populate the prefetched relationships. This
4748 may or may not be what you want.
4752 If you specify a condition on a prefetched relationship, ONLY those
4753 rows that match the prefetched condition will be fetched into that relationship.
4754 This means that adding prefetch to a search() B<may alter> what is returned by
4755 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4757 my $artist_rs = $schema->resultset('Artist')->search({
4763 my $count = $artist_rs->first->cds->count;
4765 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4767 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4769 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4771 That cmp_ok() may or may not pass depending on the datasets involved. In other
4772 words the C<WHERE> condition would apply to the entire dataset, just like
4773 it would in regular SQL. If you want to add a condition only to the "right side"
4774 of a C<LEFT JOIN> - consider declaring and using a L<relationship with a custom
4775 condition|DBIx::Class::Relationship::Base/condition>
4779 =head1 DBIC BIND VALUES
4781 Because DBIC may need more information to bind values than just the column name
4782 and value itself, it uses a special format for both passing and receiving bind
4783 values. Each bind value should be composed of an arrayref of
4784 C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
4790 If present (in any form), this is what is being passed directly to bind_param.
4791 Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
4792 a single numerical type, while DBD::Pg takes a hashref if bind options.)
4794 If this is specified, all other bind options described below are ignored.
4798 If present, this is used to infer the actual bind attribute by passing to
4799 C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
4800 "data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
4802 Note that the data type is somewhat freeform (hence the sqlt_ prefix);
4803 currently drivers are expected to "Do the Right Thing" when given a common
4804 datatype name. (Not ideal, but that's what we got at this point.)
4808 Currently used to correctly allocate buffers for bind_param_inout().
4809 Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
4810 or to a sensible value based on the "data_type".
4814 Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
4815 explicitly specified they are never overridden). Also used by some weird DBDs,
4816 where the column name should be available at bind_param time (e.g. Oracle).
4820 For backwards compatibility and convenience, the following shortcuts are
4823 [ $name => $val ] === [ { dbic_colname => $name }, $val ]
4824 [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
4825 [ undef, $val ] === [ {}, $val ]
4826 $val === [ {}, $val ]
4828 =head1 FURTHER QUESTIONS?
4830 Check the list of L<additional DBIC resources|DBIx::Class/GETTING HELP/SUPPORT>.
4832 =head1 COPYRIGHT AND LICENSE
4834 This module is free software L<copyright|DBIx::Class/COPYRIGHT AND LICENSE>
4835 by the L<DBIx::Class (DBIC) authors|DBIx::Class/AUTHORS>. You can
4836 redistribute it and/or modify it under the same terms as the
4837 L<DBIx::Class library|DBIx::Class/COPYRIGHT AND LICENSE>.