1 package DBIx::Class::ResultSet;
5 use base qw/DBIx::Class/;
7 use DBIx::Class::Exception;
8 use DBIx::Class::ResultSetColumn;
9 use Scalar::Util qw/blessed weaken/;
11 use Data::Compare (); # no imports!!! guard against insane architecture
13 # not importing first() as it will clash with our own method
17 # De-duplication in _merge_attr() is disabled, but left in for reference
18 # (the merger is used for other things that ought not to be de-duped)
19 *__HM_DEDUP = sub () { 0 };
29 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class result_source/);
33 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
37 my $users_rs = $schema->resultset('User');
38 while( $user = $users_rs->next) {
39 print $user->username;
42 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
43 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
47 A ResultSet is an object which stores a set of conditions representing
48 a query. It is the backbone of DBIx::Class (i.e. the really
49 important/useful bit).
51 No SQL is executed on the database when a ResultSet is created, it
52 just stores all the conditions needed to create the query.
54 A basic ResultSet representing the data of an entire table is returned
55 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
56 L<Source|DBIx::Class::Manual::Glossary/Source> name.
58 my $users_rs = $schema->resultset('User');
60 A new ResultSet is returned from calling L</search> on an existing
61 ResultSet. The new one will contain all the conditions of the
62 original, plus any new conditions added in the C<search> call.
64 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
65 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
68 The query that the ResultSet represents is B<only> executed against
69 the database when these methods are called:
70 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
72 If a resultset is used in a numeric context it returns the L</count>.
73 However, if it is used in a boolean context it is B<always> true. So if
74 you want to check if a resultset has any results, you must use C<if $rs
77 =head1 CUSTOM ResultSet CLASSES THAT USE Moose
79 If you want to make your custom ResultSet classes with L<Moose>, use a template
82 package MyApp::Schema::ResultSet::User;
85 use namespace::autoclean;
87 extends 'DBIx::Class::ResultSet';
89 sub BUILDARGS { $_[2] }
93 __PACKAGE__->meta->make_immutable;
97 The L<MooseX::NonMoose> is necessary so that the L<Moose> constructor does not
98 clash with the regular ResultSet constructor. Alternatively, you can use:
100 __PACKAGE__->meta->make_immutable(inline_constructor => 0);
102 The L<BUILDARGS|Moose::Manual::Construction/BUILDARGS> is necessary because the
103 signature of the ResultSet C<new> is C<< ->new($source, \%args) >>.
107 =head2 Chaining resultsets
109 Let's say you've got a query that needs to be run to return some data
110 to the user. But, you have an authorization system in place that
111 prevents certain users from seeing certain information. So, you want
112 to construct the basic query in one method, but add constraints to it in
117 my $request = $self->get_request; # Get a request object somehow.
118 my $schema = $self->result_source->schema;
120 my $cd_rs = $schema->resultset('CD')->search({
121 title => $request->param('title'),
122 year => $request->param('year'),
125 $cd_rs = $self->apply_security_policy( $cd_rs );
127 return $cd_rs->all();
130 sub apply_security_policy {
139 =head3 Resolving conditions and attributes
141 When a resultset is chained from another resultset, conditions and
142 attributes with the same keys need resolving.
144 L</join>, L</prefetch>, L</+select>, L</+as> attributes are merged
145 into the existing ones from the original resultset.
147 The L</where> and L</having> attributes, and any search conditions, are
148 merged with an SQL C<AND> to the existing condition from the original
151 All other attributes are overridden by any new ones supplied in the
154 =head2 Multiple queries
156 Since a resultset just defines a query, you can do all sorts of
157 things with it with the same object.
159 # Don't hit the DB yet.
160 my $cd_rs = $schema->resultset('CD')->search({
161 title => 'something',
165 # Each of these hits the DB individually.
166 my $count = $cd_rs->count;
167 my $most_recent = $cd_rs->get_column('date_released')->max();
168 my @records = $cd_rs->all;
170 And it's not just limited to SELECT statements.
176 $cd_rs->create({ artist => 'Fred' });
178 Which is the same as:
180 $schema->resultset('CD')->create({
181 title => 'something',
186 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
194 =item Arguments: $source, \%$attrs
196 =item Return Value: $rs
200 The resultset constructor. Takes a source object (usually a
201 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
202 L</ATTRIBUTES> below). Does not perform any queries -- these are
203 executed as needed by the other methods.
205 Generally you won't need to construct a resultset manually. You'll
206 automatically get one from e.g. a L</search> called in scalar context:
208 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
214 If called on an object, proxies to L</new_result> instead, so
216 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
218 will return a CD object, not a ResultSet, and is equivalent to:
220 my $cd = $schema->resultset('CD')->new_result({ title => 'Spoon' });
222 Please also keep in mind that many internals call C<new_result> directly,
223 so overloading this method with the idea of intercepting new result object
224 creation B<will not work>. See also warning pertaining to L</create>.
232 return $class->new_result(@_) if ref $class;
234 my ($source, $attrs) = @_;
235 $source = $source->resolve
236 if $source->isa('DBIx::Class::ResultSourceHandle');
237 $attrs = { %{$attrs||{}} };
239 if ($attrs->{page}) {
240 $attrs->{rows} ||= 10;
243 $attrs->{alias} ||= 'me';
246 result_source => $source,
247 cond => $attrs->{where},
252 # if there is a dark selector, this means we are already in a
253 # chain and the cleanup/sanification was taken care of by
255 $self->_normalize_selection($attrs)
256 unless $attrs->{_dark_selector};
259 $attrs->{result_class} || $source->result_class
269 =item Arguments: $cond, \%attrs?
271 =item Return Value: $resultset (scalar context) || @row_objs (list context)
275 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
276 my $new_rs = $cd_rs->search({ year => 2005 });
278 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
279 # year = 2005 OR year = 2004
281 In list context, C<< ->all() >> is called implicitly on the resultset, thus
282 returning a list of row objects instead. To avoid that, use L</search_rs>.
284 If you need to pass in additional attributes but no additional condition,
285 call it as C<search(undef, \%attrs)>.
287 # "SELECT name, artistid FROM $artist_table"
288 my @all_artists = $schema->resultset('Artist')->search(undef, {
289 columns => [qw/name artistid/],
292 For a list of attributes that can be passed to C<search>, see
293 L</ATTRIBUTES>. For more examples of using this function, see
294 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
295 documentation for the first argument, see L<SQL::Abstract>
296 and its extension L<DBIx::Class::SQLMaker>.
298 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
302 Note that L</search> does not process/deflate any of the values passed in the
303 L<SQL::Abstract>-compatible search condition structure. This is unlike other
304 condition-bound methods L</new>, L</create> and L</find>. The user must ensure
305 manually that any value passed to this method will stringify to something the
306 RDBMS knows how to deal with. A notable example is the handling of L<DateTime>
307 objects, for more info see:
308 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
314 my $rs = $self->search_rs( @_ );
319 elsif (defined wantarray) {
323 # we can be called by a relationship helper, which in
324 # turn may be called in void context due to some braindead
325 # overload or whatever else the user decided to be clever
326 # at this particular day. Thus limit the exception to
327 # external code calls only
328 $self->throw_exception ('->search is *not* a mutator, calling it in void context makes no sense')
329 if (caller)[0] !~ /^\QDBIx::Class::/;
339 =item Arguments: $cond, \%attrs?
341 =item Return Value: $resultset
345 This method does the same exact thing as search() except it will
346 always return a resultset, even in list context.
353 # Special-case handling for (undef, undef).
354 if ( @_ == 2 && !defined $_[1] && !defined $_[0] ) {
360 if (ref $_[-1] eq 'HASH') {
361 # copy for _normalize_selection
362 $call_attrs = { %{ pop @_ } };
364 elsif (! defined $_[-1] ) {
365 pop @_; # search({}, undef)
369 # see if we can keep the cache (no $rs changes)
371 my %safe = (alias => 1, cache => 1);
372 if ( ! List::Util::first { !$safe{$_} } keys %$call_attrs and (
375 ref $_[0] eq 'HASH' && ! keys %{$_[0]}
377 ref $_[0] eq 'ARRAY' && ! @{$_[0]}
379 $cache = $self->get_cache;
382 my $rsrc = $self->result_source;
384 my $old_attrs = { %{$self->{attrs}} };
385 my $old_having = delete $old_attrs->{having};
386 my $old_where = delete $old_attrs->{where};
388 my $new_attrs = { %$old_attrs };
390 # take care of call attrs (only if anything is changing)
391 if (keys %$call_attrs) {
393 my @selector_attrs = qw/select as columns cols +select +as +columns include_columns/;
395 # reset the current selector list if new selectors are supplied
396 if (List::Util::first { exists $call_attrs->{$_} } qw/columns cols select as/) {
397 delete @{$old_attrs}{(@selector_attrs, '_dark_selector')};
400 # Normalize the new selector list (operates on the passed-in attr structure)
401 # Need to do it on every chain instead of only once on _resolved_attrs, in
402 # order to allow detection of empty vs partial 'as'
403 $call_attrs->{_dark_selector} = $old_attrs->{_dark_selector}
404 if $old_attrs->{_dark_selector};
405 $self->_normalize_selection ($call_attrs);
407 # start with blind overwriting merge, exclude selector attrs
408 $new_attrs = { %{$old_attrs}, %{$call_attrs} };
409 delete @{$new_attrs}{@selector_attrs};
411 for (@selector_attrs) {
412 $new_attrs->{$_} = $self->_merge_attr($old_attrs->{$_}, $call_attrs->{$_})
413 if ( exists $old_attrs->{$_} or exists $call_attrs->{$_} );
416 # older deprecated name, use only if {columns} is not there
417 if (my $c = delete $new_attrs->{cols}) {
418 if ($new_attrs->{columns}) {
419 carp "Resultset specifies both the 'columns' and the legacy 'cols' attributes - ignoring 'cols'";
422 $new_attrs->{columns} = $c;
427 # join/prefetch use their own crazy merging heuristics
428 foreach my $key (qw/join prefetch/) {
429 $new_attrs->{$key} = $self->_merge_joinpref_attr($old_attrs->{$key}, $call_attrs->{$key})
430 if exists $call_attrs->{$key};
433 # stack binds together
434 $new_attrs->{bind} = [ @{ $old_attrs->{bind} || [] }, @{ $call_attrs->{bind} || [] } ];
438 # rip apart the rest of @_, parse a condition
441 if (ref $_[0] eq 'HASH') {
442 (keys %{$_[0]}) ? $_[0] : undef
448 $self->throw_exception('Odd number of arguments to search')
456 if( @_ > 1 and ! $rsrc->result_class->isa('DBIx::Class::CDBICompat') ) {
457 carp_unique 'search( %condition ) is deprecated, use search( \%condition ) instead';
460 for ($old_where, $call_cond) {
462 $new_attrs->{where} = $self->_stack_cond (
463 $_, $new_attrs->{where}
468 if (defined $old_having) {
469 $new_attrs->{having} = $self->_stack_cond (
470 $old_having, $new_attrs->{having}
474 my $rs = (ref $self)->new($rsrc, $new_attrs);
476 $rs->set_cache($cache) if ($cache);
482 sub _normalize_selection {
483 my ($self, $attrs) = @_;
486 $attrs->{'+columns'} = $self->_merge_attr($attrs->{'+columns'}, delete $attrs->{include_columns})
487 if exists $attrs->{include_columns};
489 # columns are always placed first, however
491 # Keep the X vs +X separation until _resolved_attrs time - this allows to
492 # delay the decision on whether to use a default select list ($rsrc->columns)
493 # allowing stuff like the remove_columns helper to work
495 # select/as +select/+as pairs need special handling - the amount of select/as
496 # elements in each pair does *not* have to be equal (think multicolumn
497 # selectors like distinct(foo, bar) ). If the selector is bare (no 'as'
498 # supplied at all) - try to infer the alias, either from the -as parameter
499 # of the selector spec, or use the parameter whole if it looks like a column
500 # name (ugly legacy heuristic). If all fails - leave the selector bare (which
501 # is ok as well), but make sure no more additions to the 'as' chain take place
502 for my $pref ('', '+') {
504 my ($sel, $as) = map {
505 my $key = "${pref}${_}";
507 my $val = [ ref $attrs->{$key} eq 'ARRAY'
509 : $attrs->{$key} || ()
511 delete $attrs->{$key};
515 if (! @$as and ! @$sel ) {
518 elsif (@$as and ! @$sel) {
519 $self->throw_exception(
520 "Unable to handle ${pref}as specification (@$as) without a corresponding ${pref}select"
524 # no as part supplied at all - try to deduce (unless explicit end of named selection is declared)
525 # if any @$as has been supplied we assume the user knows what (s)he is doing
526 # and blindly keep stacking up pieces
527 unless ($attrs->{_dark_selector}) {
530 if ( ref $_ eq 'HASH' and exists $_->{-as} ) {
531 push @$as, $_->{-as};
533 # assume any plain no-space, no-parenthesis string to be a column spec
534 # FIXME - this is retarded but is necessary to support shit like 'count(foo)'
535 elsif ( ! ref $_ and $_ =~ /^ [^\s\(\)]+ $/x) {
538 # if all else fails - raise a flag that no more aliasing will be allowed
540 $attrs->{_dark_selector} = {
542 string => ($dark_sel_dumper ||= do {
543 require Data::Dumper::Concise;
544 Data::Dumper::Concise::DumperObject()->Indent(0);
545 })->Values([$_])->Dump
553 elsif (@$as < @$sel) {
554 $self->throw_exception(
555 "Unable to handle an ${pref}as specification (@$as) with less elements than the corresponding ${pref}select"
558 elsif ($pref and $attrs->{_dark_selector}) {
559 $self->throw_exception(
560 "Unable to process named '+select', resultset contains an unnamed selector $attrs->{_dark_selector}{string}"
566 $attrs->{"${pref}select"} = $self->_merge_attr($attrs->{"${pref}select"}, $sel);
567 $attrs->{"${pref}as"} = $self->_merge_attr($attrs->{"${pref}as"}, $as);
572 my ($self, $left, $right) = @_;
574 # collapse single element top-level conditions
575 # (single pass only, unlikely to need recursion)
576 for ($left, $right) {
577 if (ref $_ eq 'ARRAY') {
585 elsif (ref $_ eq 'HASH') {
586 my ($first, $more) = keys %$_;
589 if (! defined $first) {
593 elsif (! defined $more) {
594 if ($first eq '-and' and ref $_->{'-and'} eq 'HASH') {
597 elsif ($first eq '-or' and ref $_->{'-or'} eq 'ARRAY') {
604 # merge hashes with weeding out of duplicates (simple cases only)
605 if (ref $left eq 'HASH' and ref $right eq 'HASH') {
607 # shallow copy to destroy
608 $right = { %$right };
609 for (grep { exists $right->{$_} } keys %$left) {
610 # the use of eq_deeply here is justified - the rhs of an
611 # expression can contain a lot of twisted weird stuff
612 delete $right->{$_} if Data::Compare::Compare( $left->{$_}, $right->{$_} );
615 $right = undef unless keys %$right;
619 if (defined $left xor defined $right) {
620 return defined $left ? $left : $right;
622 elsif (! defined $left) {
626 return { -and => [ $left, $right ] };
630 =head2 search_literal
632 B<CAVEAT>: C<search_literal> is provided for Class::DBI compatibility and
633 should only be used in that context. C<search_literal> is a convenience
634 method. It is equivalent to calling C<< $schema->search(\[]) >>, but if you
635 want to ensure columns are bound correctly, use L</search>.
637 See L<DBIx::Class::Manual::Cookbook/Searching> and
638 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
639 require C<search_literal>.
643 =item Arguments: $sql_fragment, @standalone_bind_values
645 =item Return Value: $resultset (scalar context) || @row_objs (list context)
649 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
650 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
652 Pass a literal chunk of SQL to be added to the conditional part of the
655 Example of how to use C<search> instead of C<search_literal>
657 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
658 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
663 my ($self, $sql, @bind) = @_;
665 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
668 return $self->search(\[ $sql, map [ {} => $_ ], @bind ], ($attr || () ));
675 =item Arguments: \%columns_values | @pk_values, \%attrs?
677 =item Return Value: $row_object | undef
681 Finds and returns a single row based on supplied criteria. Takes either a
682 hashref with the same format as L</create> (including inference of foreign
683 keys from related objects), or a list of primary key values in the same
684 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
685 declaration on the L</result_source>.
687 In either case an attempt is made to combine conditions already existing on
688 the resultset with the condition passed to this method.
690 To aid with preparing the correct query for the storage you may supply the
691 C<key> attribute, which is the name of a
692 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
693 unique constraint corresponding to the
694 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
695 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
696 to construct a query that satisfies the named unique constraint fully (
697 non-NULL values for each column member of the constraint) an exception is
700 If no C<key> is specified, the search is carried over all unique constraints
701 which are fully defined by the available condition.
703 If no such constraint is found, C<find> currently defaults to a simple
704 C<< search->(\%column_values) >> which may or may not do what you expect.
705 Note that this fallback behavior may be deprecated in further versions. If
706 you need to search with arbitrary conditions - use L</search>. If the query
707 resulting from this fallback produces more than one row, a warning to the
708 effect is issued, though only the first row is constructed and returned as
711 In addition to C<key>, L</find> recognizes and applies standard
712 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
714 Note that if you have extra concerns about the correctness of the resulting
715 query you need to specify the C<key> attribute and supply the entire condition
716 as an argument to find (since it is not always possible to perform the
717 combination of the resultset condition with the supplied one, especially if
718 the resultset condition contains literal sql).
720 For example, to find a row by its primary key:
722 my $cd = $schema->resultset('CD')->find(5);
724 You can also find a row by a specific unique constraint:
726 my $cd = $schema->resultset('CD')->find(
728 artist => 'Massive Attack',
729 title => 'Mezzanine',
731 { key => 'cd_artist_title' }
734 See also L</find_or_create> and L</update_or_create>.
740 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
742 my $rsrc = $self->result_source;
745 if (exists $attrs->{key}) {
746 $constraint_name = defined $attrs->{key}
748 : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
752 # Parse out the condition from input
755 if (ref $_[0] eq 'HASH') {
756 $call_cond = { %{$_[0]} };
759 # if only values are supplied we need to default to 'primary'
760 $constraint_name = 'primary' unless defined $constraint_name;
762 my @c_cols = $rsrc->unique_constraint_columns($constraint_name);
764 $self->throw_exception(
765 "No constraint columns, maybe a malformed '$constraint_name' constraint?"
768 $self->throw_exception (
769 'find() expects either a column/value hashref, or a list of values '
770 . "corresponding to the columns of the specified unique constraint '$constraint_name'"
771 ) unless @c_cols == @_;
774 @{$call_cond}{@c_cols} = @_;
778 for my $key (keys %$call_cond) {
780 my $keyref = ref($call_cond->{$key})
782 my $relinfo = $rsrc->relationship_info($key)
784 my $val = delete $call_cond->{$key};
786 next if $keyref eq 'ARRAY'; # has_many for multi_create
788 my $rel_q = $rsrc->_resolve_condition(
789 $relinfo->{cond}, $val, $key, $key
791 die "Can't handle complex relationship conditions in find" if ref($rel_q) ne 'HASH';
792 @related{keys %$rel_q} = values %$rel_q;
796 # relationship conditions take precedence (?)
797 @{$call_cond}{keys %related} = values %related;
799 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
801 if (defined $constraint_name) {
802 $final_cond = $self->_qualify_cond_columns (
804 $self->_build_unique_cond (
812 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
813 # This means that we got here after a merger of relationship conditions
814 # in ::Relationship::Base::search_related (the row method), and furthermore
815 # the relationship is of the 'single' type. This means that the condition
816 # provided by the relationship (already attached to $self) is sufficient,
817 # as there can be only one row in the database that would satisfy the
821 # no key was specified - fall down to heuristics mode:
822 # run through all unique queries registered on the resultset, and
823 # 'OR' all qualifying queries together
824 my (@unique_queries, %seen_column_combinations);
825 for my $c_name ($rsrc->unique_constraint_names) {
826 next if $seen_column_combinations{
827 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
830 push @unique_queries, try {
831 $self->_build_unique_cond ($c_name, $call_cond, 'croak_on_nulls')
835 $final_cond = @unique_queries
836 ? [ map { $self->_qualify_cond_columns($_, $alias) } @unique_queries ]
837 : $self->_non_unique_find_fallback ($call_cond, $attrs)
841 # Run the query, passing the result_class since it should propagate for find
842 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
843 if (keys %{$rs->_resolved_attrs->{collapse}}) {
845 carp "Query returned more than one row" if $rs->next;
853 # This is a stop-gap method as agreed during the discussion on find() cleanup:
854 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
856 # It is invoked when find() is called in legacy-mode with insufficiently-unique
857 # condition. It is provided for overrides until a saner way forward is devised
859 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
860 # the road. Please adjust your tests accordingly to catch this situation early
861 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
863 # The method will not be removed without an adequately complete replacement
864 # for strict-mode enforcement
865 sub _non_unique_find_fallback {
866 my ($self, $cond, $attrs) = @_;
868 return $self->_qualify_cond_columns(
870 exists $attrs->{alias}
872 : $self->{attrs}{alias}
877 sub _qualify_cond_columns {
878 my ($self, $cond, $alias) = @_;
880 my %aliased = %$cond;
881 for (keys %aliased) {
882 $aliased{"$alias.$_"} = delete $aliased{$_}
889 sub _build_unique_cond {
890 my ($self, $constraint_name, $extra_cond, $croak_on_null) = @_;
892 my @c_cols = $self->result_source->unique_constraint_columns($constraint_name);
894 # combination may fail if $self->{cond} is non-trivial
895 my ($final_cond) = try {
896 $self->_merge_with_rscond ($extra_cond)
901 # trim out everything not in $columns
902 $final_cond = { map {
903 exists $final_cond->{$_}
904 ? ( $_ => $final_cond->{$_} )
908 if (my @missing = grep
909 { ! ($croak_on_null ? defined $final_cond->{$_} : exists $final_cond->{$_}) }
912 $self->throw_exception( sprintf ( "Unable to satisfy requested constraint '%s', no values for column(s): %s",
914 join (', ', map { "'$_'" } @missing),
921 !$ENV{DBIC_NULLABLE_KEY_NOWARN}
923 my @undefs = sort grep { ! defined $final_cond->{$_} } (keys %$final_cond)
925 carp_unique ( sprintf (
926 "NULL/undef values supplied for requested unique constraint '%s' (NULL "
927 . 'values in column(s): %s). This is almost certainly not what you wanted, '
928 . 'though you can set DBIC_NULLABLE_KEY_NOWARN to disable this warning.',
930 join (', ', map { "'$_'" } @undefs),
937 =head2 search_related
941 =item Arguments: $rel, $cond?, \%attrs?
943 =item Return Value: $new_resultset (scalar context) || @row_objs (list context)
947 $new_rs = $cd_rs->search_related('artist', {
951 Searches the specified relationship, optionally specifying a condition and
952 attributes for matching records. See L</ATTRIBUTES> for more information.
954 In list context, C<< ->all() >> is called implicitly on the resultset, thus
955 returning a list of row objects instead. To avoid that, use L</search_related_rs>.
957 See also L</search_related_rs>.
962 return shift->related_resultset(shift)->search(@_);
965 =head2 search_related_rs
967 This method works exactly the same as search_related, except that
968 it guarantees a resultset, even in list context.
972 sub search_related_rs {
973 return shift->related_resultset(shift)->search_rs(@_);
980 =item Arguments: none
982 =item Return Value: $cursor
986 Returns a storage-driven cursor to the given resultset. See
987 L<DBIx::Class::Cursor> for more information.
994 my $attrs = $self->_resolved_attrs_copy;
996 return $self->{cursor}
997 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
998 $attrs->{where},$attrs);
1005 =item Arguments: $cond?
1007 =item Return Value: $row_object | undef
1011 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1013 Inflates the first result without creating a cursor if the resultset has
1014 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1017 While this method can take an optional search condition (just like L</search>)
1018 being a fast-code-path it does not recognize search attributes. If you need to
1019 add extra joins or similar, call L</search> and then chain-call L</single> on the
1020 L<DBIx::Class::ResultSet> returned.
1026 As of 0.08100, this method enforces the assumption that the preceding
1027 query returns only one row. If more than one row is returned, you will receive
1030 Query returned more than one row
1032 In this case, you should be using L</next> or L</find> instead, or if you really
1033 know what you are doing, use the L</rows> attribute to explicitly limit the size
1036 This method will also throw an exception if it is called on a resultset prefetching
1037 has_many, as such a prefetch implies fetching multiple rows from the database in
1038 order to assemble the resulting object.
1045 my ($self, $where) = @_;
1047 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1050 my $attrs = $self->_resolved_attrs_copy;
1052 if (keys %{$attrs->{collapse}}) {
1053 $self->throw_exception(
1054 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
1059 if (defined $attrs->{where}) {
1062 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1063 $where, delete $attrs->{where} ]
1066 $attrs->{where} = $where;
1070 my @data = $self->result_source->storage->select_single(
1071 $attrs->{from}, $attrs->{select},
1072 $attrs->{where}, $attrs
1075 return (@data ? ($self->_construct_object(@data))[0] : undef);
1081 # Recursively collapse the query, accumulating values for each column.
1083 sub _collapse_query {
1084 my ($self, $query, $collapsed) = @_;
1088 if (ref $query eq 'ARRAY') {
1089 foreach my $subquery (@$query) {
1090 next unless ref $subquery; # -or
1091 $collapsed = $self->_collapse_query($subquery, $collapsed);
1094 elsif (ref $query eq 'HASH') {
1095 if (keys %$query and (keys %$query)[0] eq '-and') {
1096 foreach my $subquery (@{$query->{-and}}) {
1097 $collapsed = $self->_collapse_query($subquery, $collapsed);
1101 foreach my $col (keys %$query) {
1102 my $value = $query->{$col};
1103 $collapsed->{$col}{$value}++;
1115 =item Arguments: $cond?
1117 =item Return Value: $resultsetcolumn
1121 my $max_length = $rs->get_column('length')->max;
1123 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1128 my ($self, $column) = @_;
1129 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
1137 =item Arguments: $cond, \%attrs?
1139 =item Return Value: $resultset (scalar context) || @row_objs (list context)
1143 # WHERE title LIKE '%blue%'
1144 $cd_rs = $rs->search_like({ title => '%blue%'});
1146 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1147 that this is simply a convenience method retained for ex Class::DBI users.
1148 You most likely want to use L</search> with specific operators.
1150 For more information, see L<DBIx::Class::Manual::Cookbook>.
1152 This method is deprecated and will be removed in 0.09. Use L</search()>
1153 instead. An example conversion is:
1155 ->search_like({ foo => 'bar' });
1159 ->search({ foo => { like => 'bar' } });
1166 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1167 .' Instead use ->search({ x => { -like => "y%" } })'
1168 .' (note the outer pair of {}s - they are important!)'
1170 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1171 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1172 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1173 return $class->search($query, { %$attrs });
1180 =item Arguments: $first, $last
1182 =item Return Value: $resultset (scalar context) || @row_objs (list context)
1186 Returns a resultset or object list representing a subset of elements from the
1187 resultset slice is called on. Indexes are from 0, i.e., to get the first
1188 three records, call:
1190 my ($one, $two, $three) = $rs->slice(0, 2);
1195 my ($self, $min, $max) = @_;
1196 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1197 $attrs->{offset} = $self->{attrs}{offset} || 0;
1198 $attrs->{offset} += $min;
1199 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1200 return $self->search(undef, $attrs);
1201 #my $slice = (ref $self)->new($self->result_source, $attrs);
1202 #return (wantarray ? $slice->all : $slice);
1209 =item Arguments: none
1211 =item Return Value: $result | undef
1215 Returns the next element in the resultset (C<undef> is there is none).
1217 Can be used to efficiently iterate over records in the resultset:
1219 my $rs = $schema->resultset('CD')->search;
1220 while (my $cd = $rs->next) {
1224 Note that you need to store the resultset object, and call C<next> on it.
1225 Calling C<< resultset('Table')->next >> repeatedly will always return the
1226 first record from the resultset.
1232 if (my $cache = $self->get_cache) {
1233 $self->{all_cache_position} ||= 0;
1234 return $cache->[$self->{all_cache_position}++];
1236 if ($self->{attrs}{cache}) {
1237 delete $self->{pager};
1238 $self->{all_cache_position} = 1;
1239 return ($self->all)[0];
1241 if ($self->{stashed_objects}) {
1242 my $obj = shift(@{$self->{stashed_objects}});
1243 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
1247 exists $self->{stashed_row}
1248 ? @{delete $self->{stashed_row}}
1249 : $self->cursor->next
1251 return undef unless (@row);
1252 my ($row, @more) = $self->_construct_object(@row);
1253 $self->{stashed_objects} = \@more if @more;
1257 sub _construct_object {
1258 my ($self, @row) = @_;
1260 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row)
1262 my @new = $self->result_class->inflate_result($self->result_source, @$info);
1263 @new = $self->{_attrs}{record_filter}->(@new)
1264 if exists $self->{_attrs}{record_filter};
1268 sub _collapse_result {
1269 my ($self, $as_proto, $row) = @_;
1273 # 'foo' => [ undef, 'foo' ]
1274 # 'foo.bar' => [ 'foo', 'bar' ]
1275 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
1277 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
1279 my %collapse = %{$self->{_attrs}{collapse}||{}};
1283 # if we're doing collapsing (has_many prefetch) we need to grab records
1284 # until the PK changes, so fill @pri_index. if not, we leave it empty so
1285 # we know we don't have to bother.
1287 # the reason for not using the collapse stuff directly is because if you
1288 # had for e.g. two artists in a row with no cds, the collapse info for
1289 # both would be NULL (undef) so you'd lose the second artist
1291 # store just the index so we can check the array positions from the row
1292 # without having to contruct the full hash
1294 if (keys %collapse) {
1295 my %pri = map { ($_ => 1) } $self->result_source->_pri_cols;
1296 foreach my $i (0 .. $#construct_as) {
1297 next if defined($construct_as[$i][0]); # only self table
1298 if (delete $pri{$construct_as[$i][1]}) {
1299 push(@pri_index, $i);
1301 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
1305 # no need to do an if, it'll be empty if @pri_index is empty anyway
1307 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
1311 do { # no need to check anything at the front, we always want the first row
1315 foreach my $this_as (@construct_as) {
1316 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
1319 push(@const_rows, \%const);
1321 } until ( # no pri_index => no collapse => drop straight out
1324 do { # get another row, stash it, drop out if different PK
1326 @copy = $self->cursor->next;
1327 $self->{stashed_row} = \@copy;
1329 # last thing in do block, counts as true if anything doesn't match
1331 # check xor defined first for NULL vs. NOT NULL then if one is
1332 # defined the other must be so check string equality
1335 (defined $pri_vals{$_} ^ defined $copy[$_])
1336 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
1341 my $alias = $self->{attrs}{alias};
1348 foreach my $const (@const_rows) {
1349 scalar @const_keys or do {
1350 @const_keys = sort { length($a) <=> length($b) } keys %$const;
1352 foreach my $key (@const_keys) {
1355 my @parts = split(/\./, $key);
1357 my $data = $const->{$key};
1358 foreach my $p (@parts) {
1359 $target = $target->[1]->{$p} ||= [];
1361 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
1362 # collapsing at this point and on final part
1363 my $pos = $collapse_pos{$cur};
1364 CK: foreach my $ck (@ckey) {
1365 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
1366 $collapse_pos{$cur} = $data;
1367 delete @collapse_pos{ # clear all positioning for sub-entries
1368 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
1375 if (exists $collapse{$cur}) {
1376 $target = $target->[-1];
1379 $target->[0] = $data;
1381 $info->[0] = $const->{$key};
1389 =head2 result_source
1393 =item Arguments: $result_source?
1395 =item Return Value: $result_source
1399 An accessor for the primary ResultSource object from which this ResultSet
1406 =item Arguments: $result_class?
1408 =item Return Value: $result_class
1412 An accessor for the class to use when creating row objects. Defaults to
1413 C<< result_source->result_class >> - which in most cases is the name of the
1414 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1416 Note that changing the result_class will also remove any components
1417 that were originally loaded in the source class via
1418 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1419 in the original source class will not run.
1424 my ($self, $result_class) = @_;
1425 if ($result_class) {
1426 unless (ref $result_class) { # don't fire this for an object
1427 $self->ensure_class_loaded($result_class);
1429 $self->_result_class($result_class);
1430 # THIS LINE WOULD BE A BUG - this accessor specifically exists to
1431 # permit the user to set result class on one result set only; it only
1432 # chains if provided to search()
1433 #$self->{attrs}{result_class} = $result_class if ref $self;
1435 $self->_result_class;
1442 =item Arguments: $cond, \%attrs??
1444 =item Return Value: $count
1448 Performs an SQL C<COUNT> with the same query as the resultset was built
1449 with to find the number of elements. Passing arguments is equivalent to
1450 C<< $rs->search ($cond, \%attrs)->count >>
1456 return $self->search(@_)->count if @_ and defined $_[0];
1457 return scalar @{ $self->get_cache } if $self->get_cache;
1459 my $attrs = $self->_resolved_attrs_copy;
1461 # this is a little optimization - it is faster to do the limit
1462 # adjustments in software, instead of a subquery
1463 my $rows = delete $attrs->{rows};
1464 my $offset = delete $attrs->{offset};
1467 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1468 $crs = $self->_count_subq_rs ($attrs);
1471 $crs = $self->_count_rs ($attrs);
1473 my $count = $crs->next;
1475 $count -= $offset if $offset;
1476 $count = $rows if $rows and $rows < $count;
1477 $count = 0 if ($count < 0);
1486 =item Arguments: $cond, \%attrs??
1488 =item Return Value: $count_rs
1492 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1493 This can be very handy for subqueries:
1495 ->search( { amount => $some_rs->count_rs->as_query } )
1497 As with regular resultsets the SQL query will be executed only after
1498 the resultset is accessed via L</next> or L</all>. That would return
1499 the same single value obtainable via L</count>.
1505 return $self->search(@_)->count_rs if @_;
1507 # this may look like a lack of abstraction (count() does about the same)
1508 # but in fact an _rs *must* use a subquery for the limits, as the
1509 # software based limiting can not be ported if this $rs is to be used
1510 # in a subquery itself (i.e. ->as_query)
1511 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1512 return $self->_count_subq_rs;
1515 return $self->_count_rs;
1520 # returns a ResultSetColumn object tied to the count query
1523 my ($self, $attrs) = @_;
1525 my $rsrc = $self->result_source;
1526 $attrs ||= $self->_resolved_attrs;
1528 my $tmp_attrs = { %$attrs };
1529 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1530 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1532 # overwrite the selector (supplied by the storage)
1533 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $attrs);
1534 $tmp_attrs->{as} = 'count';
1535 delete @{$tmp_attrs}{qw/columns/};
1537 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1543 # same as above but uses a subquery
1545 sub _count_subq_rs {
1546 my ($self, $attrs) = @_;
1548 my $rsrc = $self->result_source;
1549 $attrs ||= $self->_resolved_attrs;
1551 my $sub_attrs = { %$attrs };
1552 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1553 delete @{$sub_attrs}{qw/collapse columns as select _prefetch_selector_range order_by for/};
1555 # if we multi-prefetch we group_by something unique, as this is what we would
1556 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1557 if ( keys %{$attrs->{collapse}} ) {
1558 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1559 $rsrc->_identifying_column_set || $self->throw_exception(
1560 'Unable to construct a unique group_by criteria properly collapsing the '
1561 . 'has_many prefetch before count()'
1566 # Calculate subquery selector
1567 if (my $g = $sub_attrs->{group_by}) {
1569 my $sql_maker = $rsrc->storage->sql_maker;
1571 # necessary as the group_by may refer to aliased functions
1573 for my $sel (@{$attrs->{select}}) {
1574 $sel_index->{$sel->{-as}} = $sel
1575 if (ref $sel eq 'HASH' and $sel->{-as});
1578 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1579 # also look for named aggregates referred in the having clause
1580 # having often contains scalarrefs - thus parse it out entirely
1582 if ($attrs->{having}) {
1583 local $sql_maker->{having_bind};
1584 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1585 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1586 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1587 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1588 # if we don't unset it we screw up retarded but unfortunately working
1589 # 'MAX(foo.bar)' => { '>', 3 }
1590 $sql_maker->{name_sep} = '';
1593 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1595 my $sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1597 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1598 # and if all fails for an utterly naive quoted scalar-with-function
1600 $rquote $sep $lquote (.+?) $rquote
1602 [\s,] \w+ \. (\w+) [\s,]
1604 [\s,] $lquote (.+?) $rquote [\s,]
1606 push @parts, ($1 || $2 || $3); # one of them matched if we got here
1611 my $colpiece = $sel_index->{$_} || $_;
1613 # unqualify join-based group_by's. Arcane but possible query
1614 # also horrible horrible hack to alias a column (not a func.)
1615 # (probably need to introduce SQLA syntax)
1616 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1619 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1621 push @{$sub_attrs->{select}}, $colpiece;
1625 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1626 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1629 return $rsrc->resultset_class
1630 ->new ($rsrc, $sub_attrs)
1632 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1633 ->get_column ('count');
1640 =head2 count_literal
1642 B<CAVEAT>: C<count_literal> is provided for Class::DBI compatibility and
1643 should only be used in that context. See L</search_literal> for further info.
1647 =item Arguments: $sql_fragment, @standalone_bind_values
1649 =item Return Value: $count
1653 Counts the results in a literal query. Equivalent to calling L</search_literal>
1654 with the passed arguments, then L</count>.
1658 sub count_literal { shift->search_literal(@_)->count; }
1664 =item Arguments: none
1666 =item Return Value: @objects
1670 Returns all elements in the resultset.
1677 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1680 return @{ $self->get_cache } if $self->get_cache;
1684 if (keys %{$self->_resolved_attrs->{collapse}}) {
1685 # Using $self->cursor->all is really just an optimisation.
1686 # If we're collapsing has_many prefetches it probably makes
1687 # very little difference, and this is cleaner than hacking
1688 # _construct_object to survive the approach
1689 $self->cursor->reset;
1690 my @row = $self->cursor->next;
1692 push(@obj, $self->_construct_object(@row));
1693 @row = (exists $self->{stashed_row}
1694 ? @{delete $self->{stashed_row}}
1695 : $self->cursor->next);
1698 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1701 $self->set_cache(\@obj) if $self->{attrs}{cache};
1710 =item Arguments: none
1712 =item Return Value: $self
1716 Resets the resultset's cursor, so you can iterate through the elements again.
1717 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1724 delete $self->{_attrs} if exists $self->{_attrs};
1725 $self->{all_cache_position} = 0;
1726 $self->cursor->reset;
1734 =item Arguments: none
1736 =item Return Value: $object | undef
1740 Resets the resultset and returns an object for the first result (or C<undef>
1741 if the resultset is empty).
1746 return $_[0]->reset->next;
1752 # Determines whether and what type of subquery is required for the $rs operation.
1753 # If grouping is necessary either supplies its own, or verifies the current one
1754 # After all is done delegates to the proper storage method.
1756 sub _rs_update_delete {
1757 my ($self, $op, $values) = @_;
1759 my $cond = $self->{cond};
1760 my $rsrc = $self->result_source;
1761 my $storage = $rsrc->schema->storage;
1763 my $attrs = { %{$self->_resolved_attrs} };
1765 my $existing_group_by = delete $attrs->{group_by};
1766 my $needs_subq = defined $existing_group_by;
1768 # simplify the joinmap and maybe decide if a subquery is necessary
1769 my $relation_classifications = {};
1771 if (ref($attrs->{from}) eq 'ARRAY') {
1772 # if we already know we need a subq, no point of classifying relations
1773 if (!$needs_subq and @{$attrs->{from}} > 1) {
1774 $attrs->{from} = $storage->_prune_unused_joins ($attrs->{from}, $attrs->{select}, $cond, $attrs);
1776 $relation_classifications = $storage->_resolve_aliastypes_from_select_args (
1777 [ @{$attrs->{from}}[1 .. $#{$attrs->{from}}] ],
1785 $needs_subq ||= 1; # if {from} is unparseable assume the worst
1788 # do we need anything like a subquery?
1792 ! keys %{ $relation_classifications->{restricting} || {} }
1794 ! $self->_has_resolved_attr(qw/rows offset/) # limits call for a subq
1796 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1797 # a condition containing 'me' or other table prefixes will not work
1798 # at all. Tell SQLMaker to dequalify idents via a gross hack.
1800 my $sqla = $rsrc->storage->sql_maker;
1801 local $sqla->{_dequalify_idents} = 1;
1802 \[ $sqla->_recurse_where($self->{cond}) ];
1804 return $rsrc->storage->$op(
1806 $op eq 'update' ? $values : (),
1811 # we got this far - means it is time to wrap a subquery
1812 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1814 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1820 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1821 delete $attrs->{$_} for qw/collapse _collapse_order_by select _prefetch_selector_range as/;
1822 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1823 $attrs->{group_by} = \ ''; # FIXME - this is an evil hack, it causes the optimiser to kick in and throw away the LEFT joins
1824 my $subrs = (ref $self)->new($rsrc, $attrs);
1826 if (@$idcols == 1) {
1827 return $storage->$op (
1829 $op eq 'update' ? $values : (),
1830 { $idcols->[0] => { -in => $subrs->as_query } },
1833 elsif ($storage->_use_multicolumn_in) {
1834 # This is hideously ugly, but SQLA does not understand multicol IN expressions
1835 my $sql_maker = $storage->sql_maker;
1836 my ($sql, @bind) = @${$subrs->as_query};
1837 $sql = sprintf ('(%s) IN %s', # the as_query already comes with a set of parenthesis
1838 join (', ', map { $sql_maker->_quote ($_) } @$idcols),
1842 return $storage->$op (
1844 $op eq 'update' ? $values : (),
1850 # if all else fails - get all primary keys and operate over a ORed set
1851 # wrap in a transaction for consistency
1852 # this is where the group_by starts to matter
1856 keys %{ $relation_classifications->{multiplying} || {} }
1858 # make sure if there is a supplied group_by it matches the columns compiled above
1859 # perfectly. Anything else can not be sanely executed on most databases so croak
1860 # right then and there
1861 if ($existing_group_by) {
1862 my @current_group_by = map
1863 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1868 join ("\x00", sort @current_group_by)
1870 join ("\x00", sort @{$attrs->{columns}} )
1872 $self->throw_exception (
1873 "You have just attempted a $op operation on a resultset which does group_by"
1874 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1875 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1876 . ' kind of queries. Please retry the operation with a modified group_by or'
1877 . ' without using one at all.'
1882 $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
1885 my $guard = $storage->txn_scope_guard;
1888 for my $row ($subrs->cursor->all) {
1889 push @op_condition, { map
1890 { $idcols->[$_] => $row->[$_] }
1895 my $res = $storage->$op (
1897 $op eq 'update' ? $values : (),
1911 =item Arguments: \%values
1913 =item Return Value: $storage_rv
1917 Sets the specified columns in the resultset to the supplied values in a
1918 single query. Note that this will not run any accessor/set_column/update
1919 triggers, nor will it update any row object instances derived from this
1920 resultset (this includes the contents of the L<resultset cache|/set_cache>
1921 if any). See L</update_all> if you need to execute any on-update
1922 triggers or cascades defined either by you or a
1923 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1925 The return value is a pass through of what the underlying
1926 storage backend returned, and may vary. See L<DBI/execute> for the most
1931 Note that L</update> does not process/deflate any of the values passed in.
1932 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
1933 ensure manually that any value passed to this method will stringify to
1934 something the RDBMS knows how to deal with. A notable example is the
1935 handling of L<DateTime> objects, for more info see:
1936 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
1941 my ($self, $values) = @_;
1942 $self->throw_exception('Values for update must be a hash')
1943 unless ref $values eq 'HASH';
1945 return $self->_rs_update_delete ('update', $values);
1952 =item Arguments: \%values
1954 =item Return Value: 1
1958 Fetches all objects and updates them one at a time via
1959 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
1960 triggers, while L</update> will not.
1965 my ($self, $values) = @_;
1966 $self->throw_exception('Values for update_all must be a hash')
1967 unless ref $values eq 'HASH';
1969 my $guard = $self->result_source->schema->txn_scope_guard;
1970 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
1979 =item Arguments: none
1981 =item Return Value: $storage_rv
1985 Deletes the rows matching this resultset in a single query. Note that this
1986 will not run any delete triggers, nor will it alter the
1987 L<in_storage|DBIx::Class::Row/in_storage> status of any row object instances
1988 derived from this resultset (this includes the contents of the
1989 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
1990 execute any on-delete triggers or cascades defined either by you or a
1991 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1993 The return value is a pass through of what the underlying storage backend
1994 returned, and may vary. See L<DBI/execute> for the most common case.
2000 $self->throw_exception('delete does not accept any arguments')
2003 return $self->_rs_update_delete ('delete');
2010 =item Arguments: none
2012 =item Return Value: 1
2016 Fetches all objects and deletes them one at a time via
2017 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2018 triggers, while L</delete> will not.
2024 $self->throw_exception('delete_all does not accept any arguments')
2027 my $guard = $self->result_source->schema->txn_scope_guard;
2028 $_->delete for $self->all;
2037 =item Arguments: \@data;
2041 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
2042 For the arrayref of hashrefs style each hashref should be a structure suitable
2043 for submitting to a $resultset->create(...) method.
2045 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
2046 to insert the data, as this is a faster method.
2048 Otherwise, each set of data is inserted into the database using
2049 L<DBIx::Class::ResultSet/create>, and the resulting objects are
2050 accumulated into an array. The array itself, or an array reference
2051 is returned depending on scalar or list context.
2053 Example: Assuming an Artist Class that has many CDs Classes relating:
2055 my $Artist_rs = $schema->resultset("Artist");
2057 ## Void Context Example
2058 $Artist_rs->populate([
2059 { artistid => 4, name => 'Manufactured Crap', cds => [
2060 { title => 'My First CD', year => 2006 },
2061 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2064 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2065 { title => 'My parents sold me to a record company', year => 2005 },
2066 { title => 'Why Am I So Ugly?', year => 2006 },
2067 { title => 'I Got Surgery and am now Popular', year => 2007 }
2072 ## Array Context Example
2073 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
2074 { name => "Artist One"},
2075 { name => "Artist Two"},
2076 { name => "Artist Three", cds=> [
2077 { title => "First CD", year => 2007},
2078 { title => "Second CD", year => 2008},
2082 print $ArtistOne->name; ## response is 'Artist One'
2083 print $ArtistThree->cds->count ## reponse is '2'
2085 For the arrayref of arrayrefs style, the first element should be a list of the
2086 fieldsnames to which the remaining elements are rows being inserted. For
2089 $Arstist_rs->populate([
2090 [qw/artistid name/],
2091 [100, 'A Formally Unknown Singer'],
2092 [101, 'A singer that jumped the shark two albums ago'],
2093 [102, 'An actually cool singer'],
2096 Please note an important effect on your data when choosing between void and
2097 wantarray context. Since void context goes straight to C<insert_bulk> in
2098 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
2099 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
2100 create primary keys for you, you will find that your PKs are empty. In this
2101 case you will have to use the wantarray context in order to create those
2109 # cruft placed in standalone method
2110 my $data = $self->_normalize_populate_args(@_);
2112 return unless @$data;
2114 if(defined wantarray) {
2116 foreach my $item (@$data) {
2117 push(@created, $self->create($item));
2119 return wantarray ? @created : \@created;
2122 my $first = $data->[0];
2124 # if a column is a registered relationship, and is a non-blessed hash/array, consider
2125 # it relationship data
2126 my (@rels, @columns);
2127 my $rsrc = $self->result_source;
2128 my $rels = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2129 for (keys %$first) {
2130 my $ref = ref $first->{$_};
2131 $rels->{$_} && ($ref eq 'ARRAY' or $ref eq 'HASH')
2137 my @pks = $rsrc->primary_columns;
2139 ## do the belongs_to relationships
2140 foreach my $index (0..$#$data) {
2142 # delegate to create() for any dataset without primary keys with specified relationships
2143 if (grep { !defined $data->[$index]->{$_} } @pks ) {
2145 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
2146 my @ret = $self->populate($data);
2152 foreach my $rel (@rels) {
2153 next unless ref $data->[$index]->{$rel} eq "HASH";
2154 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
2155 my ($reverse_relname, $reverse_relinfo) = %{$rsrc->reverse_relationship_info($rel)};
2156 my $related = $result->result_source->_resolve_condition(
2157 $reverse_relinfo->{cond},
2163 delete $data->[$index]->{$rel};
2164 $data->[$index] = {%{$data->[$index]}, %$related};
2166 push @columns, keys %$related if $index == 0;
2170 ## inherit the data locked in the conditions of the resultset
2171 my ($rs_data) = $self->_merge_with_rscond({});
2172 delete @{$rs_data}{@columns};
2173 my @inherit_cols = keys %$rs_data;
2174 my @inherit_data = values %$rs_data;
2176 ## do bulk insert on current row
2177 $rsrc->storage->insert_bulk(
2179 [@columns, @inherit_cols],
2180 [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
2183 ## do the has_many relationships
2184 foreach my $item (@$data) {
2188 foreach my $rel (@rels) {
2189 next unless ref $item->{$rel} eq "ARRAY" && @{ $item->{$rel} };
2191 $main_row ||= $self->new_result({map { $_ => $item->{$_} } @pks});
2193 my $child = $main_row->$rel;
2195 my $related = $child->result_source->_resolve_condition(
2196 $rels->{$rel}{cond},
2202 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
2203 my @populate = map { {%$_, %$related} } @rows_to_add;
2205 $child->populate( \@populate );
2212 # populate() argumnets went over several incarnations
2213 # What we ultimately support is AoH
2214 sub _normalize_populate_args {
2215 my ($self, $arg) = @_;
2217 if (ref $arg eq 'ARRAY') {
2221 elsif (ref $arg->[0] eq 'HASH') {
2224 elsif (ref $arg->[0] eq 'ARRAY') {
2226 my @colnames = @{$arg->[0]};
2227 foreach my $values (@{$arg}[1 .. $#$arg]) {
2228 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
2234 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2241 =item Arguments: none
2243 =item Return Value: $pager
2247 Return Value a L<Data::Page> object for the current resultset. Only makes
2248 sense for queries with a C<page> attribute.
2250 To get the full count of entries for a paged resultset, call
2251 C<total_entries> on the L<Data::Page> object.
2258 return $self->{pager} if $self->{pager};
2260 my $attrs = $self->{attrs};
2261 if (!defined $attrs->{page}) {
2262 $self->throw_exception("Can't create pager for non-paged rs");
2264 elsif ($attrs->{page} <= 0) {
2265 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2267 $attrs->{rows} ||= 10;
2269 # throw away the paging flags and re-run the count (possibly
2270 # with a subselect) to get the real total count
2271 my $count_attrs = { %$attrs };
2272 delete $count_attrs->{$_} for qw/rows offset page pager/;
2274 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2276 require DBIx::Class::ResultSet::Pager;
2277 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2278 sub { $total_rs->count }, #lazy-get the total
2280 $self->{attrs}{page},
2288 =item Arguments: $page_number
2290 =item Return Value: $rs
2294 Returns a resultset for the $page_number page of the resultset on which page
2295 is called, where each page contains a number of rows equal to the 'rows'
2296 attribute set on the resultset (10 by default).
2301 my ($self, $page) = @_;
2302 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2309 =item Arguments: \%vals
2311 =item Return Value: $rowobject
2315 Creates a new row object in the resultset's result class and returns
2316 it. The row is not inserted into the database at this point, call
2317 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2318 will tell you whether the row object has been inserted or not.
2320 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2325 my ($self, $values) = @_;
2327 $self->throw_exception( "new_result takes only one argument - a hashref of values" )
2330 $self->throw_exception( "new_result expects a hashref" )
2331 unless (ref $values eq 'HASH');
2333 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2337 @$cols_from_relations
2338 ? (-cols_from_relations => $cols_from_relations)
2340 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2343 return $self->result_class->new(\%new);
2346 # _merge_with_rscond
2348 # Takes a simple hash of K/V data and returns its copy merged with the
2349 # condition already present on the resultset. Additionally returns an
2350 # arrayref of value/condition names, which were inferred from related
2351 # objects (this is needed for in-memory related objects)
2352 sub _merge_with_rscond {
2353 my ($self, $data) = @_;
2355 my (%new_data, @cols_from_relations);
2357 my $alias = $self->{attrs}{alias};
2359 if (! defined $self->{cond}) {
2360 # just massage $data below
2362 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
2363 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
2364 @cols_from_relations = keys %new_data;
2366 elsif (ref $self->{cond} ne 'HASH') {
2367 $self->throw_exception(
2368 "Can't abstract implicit construct, resultset condition not a hash"
2372 # precendence must be given to passed values over values inherited from
2373 # the cond, so the order here is important.
2374 my $collapsed_cond = $self->_collapse_cond($self->{cond});
2375 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
2377 while ( my($col, $value) = each %implied ) {
2378 my $vref = ref $value;
2384 (keys %$value)[0] eq '='
2386 $new_data{$col} = $value->{'='};
2388 elsif( !$vref or $vref eq 'SCALAR' or blessed($value) ) {
2389 $new_data{$col} = $value;
2396 %{ $self->_remove_alias($data, $alias) },
2399 return (\%new_data, \@cols_from_relations);
2402 # _has_resolved_attr
2404 # determines if the resultset defines at least one
2405 # of the attributes supplied
2407 # used to determine if a subquery is neccessary
2409 # supports some virtual attributes:
2411 # This will scan for any joins being present on the resultset.
2412 # It is not a mere key-search but a deep inspection of {from}
2415 sub _has_resolved_attr {
2416 my ($self, @attr_names) = @_;
2418 my $attrs = $self->_resolved_attrs;
2422 for my $n (@attr_names) {
2423 if (grep { $n eq $_ } (qw/-join/) ) {
2424 $extra_checks{$n}++;
2428 my $attr = $attrs->{$n};
2430 next if not defined $attr;
2432 if (ref $attr eq 'HASH') {
2433 return 1 if keys %$attr;
2435 elsif (ref $attr eq 'ARRAY') {
2443 # a resolved join is expressed as a multi-level from
2445 $extra_checks{-join}
2447 ref $attrs->{from} eq 'ARRAY'
2449 @{$attrs->{from}} > 1
2457 # Recursively collapse the condition.
2459 sub _collapse_cond {
2460 my ($self, $cond, $collapsed) = @_;
2464 if (ref $cond eq 'ARRAY') {
2465 foreach my $subcond (@$cond) {
2466 next unless ref $subcond; # -or
2467 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2470 elsif (ref $cond eq 'HASH') {
2471 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2472 foreach my $subcond (@{$cond->{-and}}) {
2473 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2477 foreach my $col (keys %$cond) {
2478 my $value = $cond->{$col};
2479 $collapsed->{$col} = $value;
2489 # Remove the specified alias from the specified query hash. A copy is made so
2490 # the original query is not modified.
2493 my ($self, $query, $alias) = @_;
2495 my %orig = %{ $query || {} };
2498 foreach my $key (keys %orig) {
2500 $unaliased{$key} = $orig{$key};
2503 $unaliased{$1} = $orig{$key}
2504 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2514 =item Arguments: none
2516 =item Return Value: \[ $sql, L<@bind_values|/DBIC BIND VALUES> ]
2520 Returns the SQL query and bind vars associated with the invocant.
2522 This is generally used as the RHS for a subquery.
2529 my $attrs = $self->_resolved_attrs_copy;
2534 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2535 # $sql also has no wrapping parenthesis in list ctx
2537 my $sqlbind = $self->result_source->storage
2538 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2547 =item Arguments: \%vals, \%attrs?
2549 =item Return Value: $rowobject
2553 my $artist = $schema->resultset('Artist')->find_or_new(
2554 { artist => 'fred' }, { key => 'artists' });
2556 $cd->cd_to_producer->find_or_new({ producer => $producer },
2557 { key => 'primary });
2559 Find an existing record from this resultset using L</find>. if none exists,
2560 instantiate a new result object and return it. The object will not be saved
2561 into your storage until you call L<DBIx::Class::Row/insert> on it.
2563 You most likely want this method when looking for existing rows using a unique
2564 constraint that is not the primary key, or looking for related rows.
2566 If you want objects to be saved immediately, use L</find_or_create> instead.
2568 B<Note>: Make sure to read the documentation of L</find> and understand the
2569 significance of the C<key> attribute, as its lack may skew your search, and
2570 subsequently result in spurious new objects.
2572 B<Note>: Take care when using C<find_or_new> with a table having
2573 columns with default values that you intend to be automatically
2574 supplied by the database (e.g. an auto_increment primary key column).
2575 In normal usage, the value of such columns should NOT be included at
2576 all in the call to C<find_or_new>, even when set to C<undef>.
2582 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2583 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2584 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2587 return $self->new_result($hash);
2594 =item Arguments: \%vals
2596 =item Return Value: a L<DBIx::Class::Row> $object
2600 Attempt to create a single new row or a row with multiple related rows
2601 in the table represented by the resultset (and related tables). This
2602 will not check for duplicate rows before inserting, use
2603 L</find_or_create> to do that.
2605 To create one row for this resultset, pass a hashref of key/value
2606 pairs representing the columns of the table and the values you wish to
2607 store. If the appropriate relationships are set up, foreign key fields
2608 can also be passed an object representing the foreign row, and the
2609 value will be set to its primary key.
2611 To create related objects, pass a hashref of related-object column values
2612 B<keyed on the relationship name>. If the relationship is of type C<multi>
2613 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2614 The process will correctly identify columns holding foreign keys, and will
2615 transparently populate them from the keys of the corresponding relation.
2616 This can be applied recursively, and will work correctly for a structure
2617 with an arbitrary depth and width, as long as the relationships actually
2618 exists and the correct column data has been supplied.
2620 Instead of hashrefs of plain related data (key/value pairs), you may
2621 also pass new or inserted objects. New objects (not inserted yet, see
2622 L</new>), will be inserted into their appropriate tables.
2624 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2626 Example of creating a new row.
2628 $person_rs->create({
2629 name=>"Some Person",
2630 email=>"somebody@someplace.com"
2633 Example of creating a new row and also creating rows in a related C<has_many>
2634 or C<has_one> resultset. Note Arrayref.
2637 { artistid => 4, name => 'Manufactured Crap', cds => [
2638 { title => 'My First CD', year => 2006 },
2639 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2644 Example of creating a new row and also creating a row in a related
2645 C<belongs_to> resultset. Note Hashref.
2648 title=>"Music for Silly Walks",
2651 name=>"Silly Musician",
2659 When subclassing ResultSet never attempt to override this method. Since
2660 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2661 lot of the internals simply never call it, so your override will be
2662 bypassed more often than not. Override either L<new|DBIx::Class::Row/new>
2663 or L<insert|DBIx::Class::Row/insert> depending on how early in the
2664 L</create> process you need to intervene. See also warning pertaining to
2672 my ($self, $attrs) = @_;
2673 $self->throw_exception( "create needs a hashref" )
2674 unless ref $attrs eq 'HASH';
2675 return $self->new_result($attrs)->insert;
2678 =head2 find_or_create
2682 =item Arguments: \%vals, \%attrs?
2684 =item Return Value: $rowobject
2688 $cd->cd_to_producer->find_or_create({ producer => $producer },
2689 { key => 'primary' });
2691 Tries to find a record based on its primary key or unique constraints; if none
2692 is found, creates one and returns that instead.
2694 my $cd = $schema->resultset('CD')->find_or_create({
2696 artist => 'Massive Attack',
2697 title => 'Mezzanine',
2701 Also takes an optional C<key> attribute, to search by a specific key or unique
2702 constraint. For example:
2704 my $cd = $schema->resultset('CD')->find_or_create(
2706 artist => 'Massive Attack',
2707 title => 'Mezzanine',
2709 { key => 'cd_artist_title' }
2712 B<Note>: Make sure to read the documentation of L</find> and understand the
2713 significance of the C<key> attribute, as its lack may skew your search, and
2714 subsequently result in spurious row creation.
2716 B<Note>: Because find_or_create() reads from the database and then
2717 possibly inserts based on the result, this method is subject to a race
2718 condition. Another process could create a record in the table after
2719 the find has completed and before the create has started. To avoid
2720 this problem, use find_or_create() inside a transaction.
2722 B<Note>: Take care when using C<find_or_create> with a table having
2723 columns with default values that you intend to be automatically
2724 supplied by the database (e.g. an auto_increment primary key column).
2725 In normal usage, the value of such columns should NOT be included at
2726 all in the call to C<find_or_create>, even when set to C<undef>.
2728 See also L</find> and L</update_or_create>. For information on how to declare
2729 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2731 If you need to know if an existing row was found or a new one created use
2732 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2733 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2736 my $cd = $schema->resultset('CD')->find_or_new({
2738 artist => 'Massive Attack',
2739 title => 'Mezzanine',
2743 if( !$cd->in_storage ) {
2750 sub find_or_create {
2752 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2753 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2754 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2757 return $self->create($hash);
2760 =head2 update_or_create
2764 =item Arguments: \%col_values, { key => $unique_constraint }?
2766 =item Return Value: $row_object
2770 $resultset->update_or_create({ col => $val, ... });
2772 Like L</find_or_create>, but if a row is found it is immediately updated via
2773 C<< $found_row->update (\%col_values) >>.
2776 Takes an optional C<key> attribute to search on a specific unique constraint.
2779 # In your application
2780 my $cd = $schema->resultset('CD')->update_or_create(
2782 artist => 'Massive Attack',
2783 title => 'Mezzanine',
2786 { key => 'cd_artist_title' }
2789 $cd->cd_to_producer->update_or_create({
2790 producer => $producer,
2796 B<Note>: Make sure to read the documentation of L</find> and understand the
2797 significance of the C<key> attribute, as its lack may skew your search, and
2798 subsequently result in spurious row creation.
2800 B<Note>: Take care when using C<update_or_create> with a table having
2801 columns with default values that you intend to be automatically
2802 supplied by the database (e.g. an auto_increment primary key column).
2803 In normal usage, the value of such columns should NOT be included at
2804 all in the call to C<update_or_create>, even when set to C<undef>.
2806 See also L</find> and L</find_or_create>. For information on how to declare
2807 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2809 If you need to know if an existing row was updated or a new one created use
2810 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2811 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2816 sub update_or_create {
2818 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2819 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2821 my $row = $self->find($cond, $attrs);
2823 $row->update($cond);
2827 return $self->create($cond);
2830 =head2 update_or_new
2834 =item Arguments: \%col_values, { key => $unique_constraint }?
2836 =item Return Value: $rowobject
2840 $resultset->update_or_new({ col => $val, ... });
2842 Like L</find_or_new> but if a row is found it is immediately updated via
2843 C<< $found_row->update (\%col_values) >>.
2847 # In your application
2848 my $cd = $schema->resultset('CD')->update_or_new(
2850 artist => 'Massive Attack',
2851 title => 'Mezzanine',
2854 { key => 'cd_artist_title' }
2857 if ($cd->in_storage) {
2858 # the cd was updated
2861 # the cd is not yet in the database, let's insert it
2865 B<Note>: Make sure to read the documentation of L</find> and understand the
2866 significance of the C<key> attribute, as its lack may skew your search, and
2867 subsequently result in spurious new objects.
2869 B<Note>: Take care when using C<update_or_new> with a table having
2870 columns with default values that you intend to be automatically
2871 supplied by the database (e.g. an auto_increment primary key column).
2872 In normal usage, the value of such columns should NOT be included at
2873 all in the call to C<update_or_new>, even when set to C<undef>.
2875 See also L</find>, L</find_or_create> and L</find_or_new>.
2881 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2882 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2884 my $row = $self->find( $cond, $attrs );
2885 if ( defined $row ) {
2886 $row->update($cond);
2890 return $self->new_result($cond);
2897 =item Arguments: none
2899 =item Return Value: \@cache_objects | undef
2903 Gets the contents of the cache for the resultset, if the cache is set.
2905 The cache is populated either by using the L</prefetch> attribute to
2906 L</search> or by calling L</set_cache>.
2918 =item Arguments: \@cache_objects
2920 =item Return Value: \@cache_objects
2924 Sets the contents of the cache for the resultset. Expects an arrayref
2925 of objects of the same class as those produced by the resultset. Note that
2926 if the cache is set the resultset will return the cached objects rather
2927 than re-querying the database even if the cache attr is not set.
2929 The contents of the cache can also be populated by using the
2930 L</prefetch> attribute to L</search>.
2935 my ( $self, $data ) = @_;
2936 $self->throw_exception("set_cache requires an arrayref")
2937 if defined($data) && (ref $data ne 'ARRAY');
2938 $self->{all_cache} = $data;
2945 =item Arguments: none
2947 =item Return Value: undef
2951 Clears the cache for the resultset.
2956 shift->set_cache(undef);
2963 =item Arguments: none
2965 =item Return Value: true, if the resultset has been paginated
2973 return !!$self->{attrs}{page};
2980 =item Arguments: none
2982 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2990 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
2993 =head2 related_resultset
2997 =item Arguments: $relationship_name
2999 =item Return Value: $resultset
3003 Returns a related resultset for the supplied relationship name.
3005 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
3009 sub related_resultset {
3010 my ($self, $rel) = @_;
3012 $self->{related_resultsets} ||= {};
3013 return $self->{related_resultsets}{$rel} ||= do {
3014 my $rsrc = $self->result_source;
3015 my $rel_info = $rsrc->relationship_info($rel);
3017 $self->throw_exception(
3018 "search_related: result source '" . $rsrc->source_name .
3019 "' has no such relationship $rel")
3022 my $attrs = $self->_chain_relationship($rel);
3024 my $join_count = $attrs->{seen_join}{$rel};
3026 my $alias = $self->result_source->storage
3027 ->relname_to_table_alias($rel, $join_count);
3029 # since this is search_related, and we already slid the select window inwards
3030 # (the select/as attrs were deleted in the beginning), we need to flip all
3031 # left joins to inner, so we get the expected results
3032 # read the comment on top of the actual function to see what this does
3033 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
3036 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3037 delete @{$attrs}{qw(result_class alias)};
3041 if (my $cache = $self->get_cache) {
3042 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
3043 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
3048 my $rel_source = $rsrc->related_source($rel);
3052 # The reason we do this now instead of passing the alias to the
3053 # search_rs below is that if you wrap/overload resultset on the
3054 # source you need to know what alias it's -going- to have for things
3055 # to work sanely (e.g. RestrictWithObject wants to be able to add
3056 # extra query restrictions, and these may need to be $alias.)
3058 my $rel_attrs = $rel_source->resultset_attributes;
3059 local $rel_attrs->{alias} = $alias;
3061 $rel_source->resultset
3065 where => $attrs->{where},
3068 $new->set_cache($new_cache) if $new_cache;
3073 =head2 current_source_alias
3077 =item Arguments: none
3079 =item Return Value: $source_alias
3083 Returns the current table alias for the result source this resultset is built
3084 on, that will be used in the SQL query. Usually it is C<me>.
3086 Currently the source alias that refers to the result set returned by a
3087 L</search>/L</find> family method depends on how you got to the resultset: it's
3088 C<me> by default, but eg. L</search_related> aliases it to the related result
3089 source name (and keeps C<me> referring to the original result set). The long
3090 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3091 (and make this method unnecessary).
3093 Thus it's currently necessary to use this method in predefined queries (see
3094 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3095 source alias of the current result set:
3097 # in a result set class
3099 my ($self, $user) = @_;
3101 my $me = $self->current_source_alias;
3103 return $self->search({
3104 "$me.modified" => $user->id,
3110 sub current_source_alias {
3113 return ($self->{attrs} || {})->{alias} || 'me';
3116 =head2 as_subselect_rs
3120 =item Arguments: none
3122 =item Return Value: $resultset
3126 Act as a barrier to SQL symbols. The resultset provided will be made into a
3127 "virtual view" by including it as a subquery within the from clause. From this
3128 point on, any joined tables are inaccessible to ->search on the resultset (as if
3129 it were simply where-filtered without joins). For example:
3131 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3133 # 'x' now pollutes the query namespace
3135 # So the following works as expected
3136 my $ok_rs = $rs->search({'x.other' => 1});
3138 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3139 # def) we look for one row with contradictory terms and join in another table
3140 # (aliased 'x_2') which we never use
3141 my $broken_rs = $rs->search({'x.name' => 'def'});
3143 my $rs2 = $rs->as_subselect_rs;
3145 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3146 my $not_joined_rs = $rs2->search({'x.other' => 1});
3148 # works as expected: finds a 'table' row related to two x rows (abc and def)
3149 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3151 Another example of when one might use this would be to select a subset of
3152 columns in a group by clause:
3154 my $rs = $schema->resultset('Bar')->search(undef, {
3155 group_by => [qw{ id foo_id baz_id }],
3156 })->as_subselect_rs->search(undef, {
3157 columns => [qw{ id foo_id }]
3160 In the above example normally columns would have to be equal to the group by,
3161 but because we isolated the group by into a subselect the above works.
3165 sub as_subselect_rs {
3168 my $attrs = $self->_resolved_attrs;
3170 my $fresh_rs = (ref $self)->new (
3171 $self->result_source
3174 # these pieces will be locked in the subquery
3175 delete $fresh_rs->{cond};
3176 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3178 return $fresh_rs->search( {}, {
3180 $attrs->{alias} => $self->as_query,
3181 -alias => $attrs->{alias},
3182 -rsrc => $self->result_source,
3184 alias => $attrs->{alias},
3188 # This code is called by search_related, and makes sure there
3189 # is clear separation between the joins before, during, and
3190 # after the relationship. This information is needed later
3191 # in order to properly resolve prefetch aliases (any alias
3192 # with a relation_chain_depth less than the depth of the
3193 # current prefetch is not considered)
3195 # The increments happen twice per join. An even number means a
3196 # relationship specified via a search_related, whereas an odd
3197 # number indicates a join/prefetch added via attributes
3199 # Also this code will wrap the current resultset (the one we
3200 # chain to) in a subselect IFF it contains limiting attributes
3201 sub _chain_relationship {
3202 my ($self, $rel) = @_;
3203 my $source = $self->result_source;
3204 my $attrs = { %{$self->{attrs}||{}} };
3206 # we need to take the prefetch the attrs into account before we
3207 # ->_resolve_join as otherwise they get lost - captainL
3208 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3210 delete @{$attrs}{qw/join prefetch collapse group_by distinct select as columns +select +as +columns/};
3212 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3215 my @force_subq_attrs = qw/offset rows group_by having/;
3218 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3220 $self->_has_resolved_attr (@force_subq_attrs)
3222 # Nuke the prefetch (if any) before the new $rs attrs
3223 # are resolved (prefetch is useless - we are wrapping
3224 # a subquery anyway).
3225 my $rs_copy = $self->search;
3226 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3227 $rs_copy->{attrs}{join},
3228 delete $rs_copy->{attrs}{prefetch},
3233 -alias => $attrs->{alias},
3234 $attrs->{alias} => $rs_copy->as_query,
3236 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3237 $seen->{-relation_chain_depth} = 0;
3239 elsif ($attrs->{from}) { #shallow copy suffices
3240 $from = [ @{$attrs->{from}} ];
3245 -alias => $attrs->{alias},
3246 $attrs->{alias} => $source->from,
3250 my $jpath = ($seen->{-relation_chain_depth})
3251 ? $from->[-1][0]{-join_path}
3254 my @requested_joins = $source->_resolve_join(
3261 push @$from, @requested_joins;
3263 $seen->{-relation_chain_depth}++;
3265 # if $self already had a join/prefetch specified on it, the requested
3266 # $rel might very well be already included. What we do in this case
3267 # is effectively a no-op (except that we bump up the chain_depth on
3268 # the join in question so we could tell it *is* the search_related)
3271 # we consider the last one thus reverse
3272 for my $j (reverse @requested_joins) {
3273 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3274 if ($rel eq $last_j) {
3275 $j->[0]{-relation_chain_depth}++;
3281 unless ($already_joined) {
3282 push @$from, $source->_resolve_join(
3290 $seen->{-relation_chain_depth}++;
3292 return {%$attrs, from => $from, seen_join => $seen};
3295 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
3296 sub _resolved_attrs_copy {
3298 return { %{$self->_resolved_attrs (@_)} };
3301 sub _resolved_attrs {
3303 return $self->{_attrs} if $self->{_attrs};
3305 my $attrs = { %{ $self->{attrs} || {} } };
3306 my $source = $self->result_source;
3307 my $alias = $attrs->{alias};
3309 # default selection list
3310 $attrs->{columns} = [ $source->columns ]
3311 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3313 # merge selectors together
3314 for (qw/columns select as/) {
3315 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3316 if $attrs->{$_} or $attrs->{"+$_"};
3319 # disassemble columns
3321 if (my $cols = delete $attrs->{columns}) {
3322 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3323 if (ref $c eq 'HASH') {
3324 for my $as (sort keys %$c) {
3325 push @sel, $c->{$as};
3336 # when trying to weed off duplicates later do not go past this point -
3337 # everything added from here on is unbalanced "anyone's guess" stuff
3338 my $dedup_stop_idx = $#as;
3340 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3342 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3343 if $attrs->{select};
3345 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3347 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_";
3350 # disqualify all $alias.col as-bits (collapser mandated)
3352 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_;
3355 # de-duplicate the result (remove *identical* select/as pairs)
3356 # and also die on duplicate {as} pointing to different {select}s
3357 # not using a c-style for as the condition is prone to shrinkage
3360 while ($i <= $dedup_stop_idx) {
3361 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3366 elsif ($seen->{$as[$i]}++) {
3367 $self->throw_exception(
3368 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3376 $attrs->{select} = \@sel;
3377 $attrs->{as} = \@as;
3379 $attrs->{from} ||= [{
3381 -alias => $self->{attrs}{alias},
3382 $self->{attrs}{alias} => $source->from,
3385 if ( $attrs->{join} || $attrs->{prefetch} ) {
3387 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3388 if ref $attrs->{from} ne 'ARRAY';
3390 my $join = (delete $attrs->{join}) || {};
3392 if ( defined $attrs->{prefetch} ) {
3393 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3396 $attrs->{from} = # have to copy here to avoid corrupting the original
3398 @{ $attrs->{from} },
3399 $source->_resolve_join(
3402 { %{ $attrs->{seen_join} || {} } },
3403 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3404 ? $attrs->{from}[-1][0]{-join_path}
3411 if ( defined $attrs->{order_by} ) {
3412 $attrs->{order_by} = (
3413 ref( $attrs->{order_by} ) eq 'ARRAY'
3414 ? [ @{ $attrs->{order_by} } ]
3415 : [ $attrs->{order_by} || () ]
3419 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3420 $attrs->{group_by} = [ $attrs->{group_by} ];
3423 # generate the distinct induced group_by early, as prefetch will be carried via a
3424 # subquery (since a group_by is present)
3425 if (delete $attrs->{distinct}) {
3426 if ($attrs->{group_by}) {
3427 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3430 # distinct affects only the main selection part, not what prefetch may
3432 $attrs->{group_by} = $source->storage->_group_over_selection (
3440 $attrs->{collapse} ||= {};
3441 if ($attrs->{prefetch}) {
3443 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3444 if $attrs->{_dark_selector};
3446 my $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} );
3448 my $prefetch_ordering = [];
3450 # this is a separate structure (we don't look in {from} directly)
3451 # as the resolver needs to shift things off the lists to work
3452 # properly (identical-prefetches on different branches)
3454 if (ref $attrs->{from} eq 'ARRAY') {
3456 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3458 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3459 next unless $j->[0]{-alias};
3460 next unless $j->[0]{-join_path};
3461 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3463 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3466 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3467 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3472 $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
3474 # we need to somehow mark which columns came from prefetch
3476 my $sel_end = $#{$attrs->{select}};
3477 $attrs->{_prefetch_selector_range} = [ $sel_end + 1, $sel_end + @prefetch ];
3480 push @{ $attrs->{select} }, (map { $_->[0] } @prefetch);
3481 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
3483 push( @{$attrs->{order_by}}, @$prefetch_ordering );
3484 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
3487 # if both page and offset are specified, produce a combined offset
3488 # even though it doesn't make much sense, this is what pre 081xx has
3490 if (my $page = delete $attrs->{page}) {
3492 ($attrs->{rows} * ($page - 1))
3494 ($attrs->{offset} || 0)
3498 return $self->{_attrs} = $attrs;
3502 my ($self, $attr) = @_;
3504 if (ref $attr eq 'HASH') {
3505 return $self->_rollout_hash($attr);
3506 } elsif (ref $attr eq 'ARRAY') {
3507 return $self->_rollout_array($attr);
3513 sub _rollout_array {
3514 my ($self, $attr) = @_;
3517 foreach my $element (@{$attr}) {
3518 if (ref $element eq 'HASH') {
3519 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3520 } elsif (ref $element eq 'ARRAY') {
3521 # XXX - should probably recurse here
3522 push( @rolled_array, @{$self->_rollout_array($element)} );
3524 push( @rolled_array, $element );
3527 return \@rolled_array;
3531 my ($self, $attr) = @_;
3534 foreach my $key (keys %{$attr}) {
3535 push( @rolled_array, { $key => $attr->{$key} } );
3537 return \@rolled_array;
3540 sub _calculate_score {
3541 my ($self, $a, $b) = @_;
3543 if (defined $a xor defined $b) {
3546 elsif (not defined $a) {
3550 if (ref $b eq 'HASH') {
3551 my ($b_key) = keys %{$b};
3552 if (ref $a eq 'HASH') {
3553 my ($a_key) = keys %{$a};
3554 if ($a_key eq $b_key) {
3555 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3560 return ($a eq $b_key) ? 1 : 0;
3563 if (ref $a eq 'HASH') {
3564 my ($a_key) = keys %{$a};
3565 return ($b eq $a_key) ? 1 : 0;
3567 return ($b eq $a) ? 1 : 0;
3572 sub _merge_joinpref_attr {
3573 my ($self, $orig, $import) = @_;
3575 return $import unless defined($orig);
3576 return $orig unless defined($import);
3578 $orig = $self->_rollout_attr($orig);
3579 $import = $self->_rollout_attr($import);
3582 foreach my $import_element ( @{$import} ) {
3583 # find best candidate from $orig to merge $b_element into
3584 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3585 foreach my $orig_element ( @{$orig} ) {
3586 my $score = $self->_calculate_score( $orig_element, $import_element );
3587 if ($score > $best_candidate->{score}) {
3588 $best_candidate->{position} = $position;
3589 $best_candidate->{score} = $score;
3593 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3594 $import_key = '' if not defined $import_key;
3596 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3597 push( @{$orig}, $import_element );
3599 my $orig_best = $orig->[$best_candidate->{position}];
3600 # merge orig_best and b_element together and replace original with merged
3601 if (ref $orig_best ne 'HASH') {
3602 $orig->[$best_candidate->{position}] = $import_element;
3603 } elsif (ref $import_element eq 'HASH') {
3604 my ($key) = keys %{$orig_best};
3605 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3608 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3619 require Hash::Merge;
3620 my $hm = Hash::Merge->new;
3622 $hm->specify_behavior({
3625 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3627 if ($defl xor $defr) {
3628 return [ $defl ? $_[0] : $_[1] ];
3633 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3637 return [$_[0], $_[1]];
3641 return $_[1] if !defined $_[0];
3642 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3643 return [$_[0], @{$_[1]}]
3646 return [] if !defined $_[0] and !keys %{$_[1]};
3647 return [ $_[1] ] if !defined $_[0];
3648 return [ $_[0] ] if !keys %{$_[1]};
3649 return [$_[0], $_[1]]
3654 return $_[0] if !defined $_[1];
3655 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3656 return [@{$_[0]}, $_[1]]
3659 my @ret = @{$_[0]} or return $_[1];
3660 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3661 my %idx = map { $_ => 1 } @ret;
3662 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3666 return [ $_[1] ] if ! @{$_[0]};
3667 return $_[0] if !keys %{$_[1]};
3668 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3669 return [ @{$_[0]}, $_[1] ];
3674 return [] if !keys %{$_[0]} and !defined $_[1];
3675 return [ $_[0] ] if !defined $_[1];
3676 return [ $_[1] ] if !keys %{$_[0]};
3677 return [$_[0], $_[1]]
3680 return [] if !keys %{$_[0]} and !@{$_[1]};
3681 return [ $_[0] ] if !@{$_[1]};
3682 return $_[1] if !keys %{$_[0]};
3683 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3684 return [ $_[0], @{$_[1]} ];
3687 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3688 return [ $_[0] ] if !keys %{$_[1]};
3689 return [ $_[1] ] if !keys %{$_[0]};
3690 return [ $_[0] ] if $_[0] eq $_[1];
3691 return [ $_[0], $_[1] ];
3694 } => 'DBIC_RS_ATTR_MERGER');
3698 return $hm->merge ($_[1], $_[2]);
3702 sub STORABLE_freeze {
3703 my ($self, $cloning) = @_;
3704 my $to_serialize = { %$self };
3706 # A cursor in progress can't be serialized (and would make little sense anyway)
3707 delete $to_serialize->{cursor};
3709 # nor is it sensical to store a not-yet-fired-count pager
3710 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3711 delete $to_serialize->{pager};
3714 Storable::nfreeze($to_serialize);
3717 # need this hook for symmetry
3719 my ($self, $cloning, $serialized) = @_;
3721 %$self = %{ Storable::thaw($serialized) };
3727 =head2 throw_exception
3729 See L<DBIx::Class::Schema/throw_exception> for details.
3733 sub throw_exception {
3736 if (ref $self and my $rsrc = $self->result_source) {
3737 $rsrc->throw_exception(@_)
3740 DBIx::Class::Exception->throw(@_);
3744 # XXX: FIXME: Attributes docs need clearing up
3748 Attributes are used to refine a ResultSet in various ways when
3749 searching for data. They can be passed to any method which takes an
3750 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3753 These are in no particular order:
3759 =item Value: ( $order_by | \@order_by | \%order_by )
3763 Which column(s) to order the results by.
3765 [The full list of suitable values is documented in
3766 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3769 If a single column name, or an arrayref of names is supplied, the
3770 argument is passed through directly to SQL. The hashref syntax allows
3771 for connection-agnostic specification of ordering direction:
3773 For descending order:
3775 order_by => { -desc => [qw/col1 col2 col3/] }
3777 For explicit ascending order:
3779 order_by => { -asc => 'col' }
3781 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3782 supported, although you are strongly encouraged to use the hashref
3783 syntax as outlined above.
3789 =item Value: \@columns
3793 Shortcut to request a particular set of columns to be retrieved. Each
3794 column spec may be a string (a table column name), or a hash (in which
3795 case the key is the C<as> value, and the value is used as the C<select>
3796 expression). Adds C<me.> onto the start of any column without a C<.> in
3797 it and sets C<select> from that, then auto-populates C<as> from
3798 C<select> as normal. (You may also use the C<cols> attribute, as in
3799 earlier versions of DBIC.)
3801 Essentially C<columns> does the same as L</select> and L</as>.
3803 columns => [ 'foo', { bar => 'baz' } ]
3807 select => [qw/foo baz/],
3814 =item Value: \@columns
3818 Indicates additional columns to be selected from storage. Works the same
3819 as L</columns> but adds columns to the selection. (You may also use the
3820 C<include_columns> attribute, as in earlier versions of DBIC). For
3823 $schema->resultset('CD')->search(undef, {
3824 '+columns' => ['artist.name'],
3828 would return all CDs and include a 'name' column to the information
3829 passed to object inflation. Note that the 'artist' is the name of the
3830 column (or relationship) accessor, and 'name' is the name of the column
3831 accessor in the related table.
3833 B<NOTE:> You need to explicitly quote '+columns' when defining the attribute.
3834 Not doing so causes Perl to incorrectly interpret +columns as a bareword with a
3835 unary plus operator before it.
3837 =head2 include_columns
3841 =item Value: \@columns
3845 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3851 =item Value: \@select_columns
3855 Indicates which columns should be selected from the storage. You can use
3856 column names, or in the case of RDBMS back ends, function or stored procedure
3859 $rs = $schema->resultset('Employee')->search(undef, {
3862 { count => 'employeeid' },
3863 { max => { length => 'name' }, -as => 'longest_name' }
3868 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
3870 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
3871 use L</select>, to instruct DBIx::Class how to store the result of the column.
3872 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
3873 identifier aliasing. You can however alias a function, so you can use it in
3874 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
3875 attribute> supplied as shown in the example above.
3877 B<NOTE:> You need to explicitly quote '+select'/'+as' when defining the attributes.
3878 Not doing so causes Perl to incorrectly interpret them as a bareword with a
3879 unary plus operator before it.
3885 Indicates additional columns to be selected from storage. Works the same as
3886 L</select> but adds columns to the default selection, instead of specifying
3895 Indicates additional column names for those added via L</+select>. See L</as>.
3903 =item Value: \@inflation_names
3907 Indicates column names for object inflation. That is L</as> indicates the
3908 slot name in which the column value will be stored within the
3909 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
3910 identifier by the C<get_column> method (or via the object accessor B<if one
3911 with the same name already exists>) as shown below. The L</as> attribute has
3912 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
3914 $rs = $schema->resultset('Employee')->search(undef, {
3917 { count => 'employeeid' },
3918 { max => { length => 'name' }, -as => 'longest_name' }
3927 If the object against which the search is performed already has an accessor
3928 matching a column name specified in C<as>, the value can be retrieved using
3929 the accessor as normal:
3931 my $name = $employee->name();
3933 If on the other hand an accessor does not exist in the object, you need to
3934 use C<get_column> instead:
3936 my $employee_count = $employee->get_column('employee_count');
3938 You can create your own accessors if required - see
3939 L<DBIx::Class::Manual::Cookbook> for details.
3945 =item Value: ($rel_name | \@rel_names | \%rel_names)
3949 Contains a list of relationships that should be joined for this query. For
3952 # Get CDs by Nine Inch Nails
3953 my $rs = $schema->resultset('CD')->search(
3954 { 'artist.name' => 'Nine Inch Nails' },
3955 { join => 'artist' }
3958 Can also contain a hash reference to refer to the other relation's relations.
3961 package MyApp::Schema::Track;
3962 use base qw/DBIx::Class/;
3963 __PACKAGE__->table('track');
3964 __PACKAGE__->add_columns(qw/trackid cd position title/);
3965 __PACKAGE__->set_primary_key('trackid');
3966 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3969 # In your application
3970 my $rs = $schema->resultset('Artist')->search(
3971 { 'track.title' => 'Teardrop' },
3973 join => { cd => 'track' },
3974 order_by => 'artist.name',
3978 You need to use the relationship (not the table) name in conditions,
3979 because they are aliased as such. The current table is aliased as "me", so
3980 you need to use me.column_name in order to avoid ambiguity. For example:
3982 # Get CDs from 1984 with a 'Foo' track
3983 my $rs = $schema->resultset('CD')->search(
3986 'tracks.name' => 'Foo'
3988 { join => 'tracks' }
3991 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3992 similarly for a third time). For e.g.
3994 my $rs = $schema->resultset('Artist')->search({
3995 'cds.title' => 'Down to Earth',
3996 'cds_2.title' => 'Popular',
3998 join => [ qw/cds cds/ ],
4001 will return a set of all artists that have both a cd with title 'Down
4002 to Earth' and a cd with title 'Popular'.
4004 If you want to fetch related objects from other tables as well, see C<prefetch>
4007 NOTE: An internal join-chain pruner will discard certain joins while
4008 constructing the actual SQL query, as long as the joins in question do not
4009 affect the retrieved result. This for example includes 1:1 left joins
4010 that are not part of the restriction specification (WHERE/HAVING) nor are
4011 a part of the query selection.
4013 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4019 =item Value: ($rel_name | \@rel_names | \%rel_names)
4023 Contains one or more relationships that should be fetched along with
4024 the main query (when they are accessed afterwards the data will
4025 already be available, without extra queries to the database). This is
4026 useful for when you know you will need the related objects, because it
4027 saves at least one query:
4029 my $rs = $schema->resultset('Tag')->search(
4038 The initial search results in SQL like the following:
4040 SELECT tag.*, cd.*, artist.* FROM tag
4041 JOIN cd ON tag.cd = cd.cdid
4042 JOIN artist ON cd.artist = artist.artistid
4044 L<DBIx::Class> has no need to go back to the database when we access the
4045 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4048 Simple prefetches will be joined automatically, so there is no need
4049 for a C<join> attribute in the above search.
4051 L</prefetch> can be used with the any of the relationship types and
4052 multiple prefetches can be specified together. Below is a more complex
4053 example that prefetches a CD's artist, its liner notes (if present),
4054 the cover image, the tracks on that cd, and the guests on those
4058 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4059 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4060 My::Schema::CD->has_one( cover_image => 'My::Schema::Artwork' );
4061 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4063 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4065 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4068 my $rs = $schema->resultset('CD')->search(
4072 { artist => 'record_label'}, # belongs_to => belongs_to
4073 'liner_note', # might_have
4074 'cover_image', # has_one
4075 { tracks => 'guests' }, # has_many => has_many
4080 This will produce SQL like the following:
4082 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4086 ON artist.artistid = me.artistid
4087 JOIN record_label record_label
4088 ON record_label.labelid = artist.labelid
4089 LEFT JOIN track tracks
4090 ON tracks.cdid = me.cdid
4091 LEFT JOIN guest guests
4092 ON guests.trackid = track.trackid
4093 LEFT JOIN liner_notes liner_note
4094 ON liner_note.cdid = me.cdid
4095 JOIN cd_artwork cover_image
4096 ON cover_image.cdid = me.cdid
4099 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4100 C<tracks>, and C<guests> of the CD will all be available through the
4101 relationship accessors without the need for additional queries to the
4104 However, there is one caveat to be observed: it can be dangerous to
4105 prefetch more than one L<has_many|DBIx::Class::Relationship/has_many>
4106 relationship on a given level. e.g.:
4108 my $rs = $schema->resultset('CD')->search(
4112 'tracks', # has_many
4113 { cd_to_producer => 'producer' }, # has_many => belongs_to (i.e. m2m)
4118 In fact, C<DBIx::Class> will emit the following warning:
4120 Prefetching multiple has_many rels tracks and cd_to_producer at top
4121 level will explode the number of row objects retrievable via ->next
4122 or ->all. Use at your own risk.
4124 The collapser currently can't identify duplicate tuples for multiple
4125 L<has_many|DBIx::Class::Relationship/has_many> relationships and as a
4126 result the second L<has_many|DBIx::Class::Relationship/has_many>
4127 relation could contain redundant objects.
4129 =head3 Using L</prefetch> with L</join>
4131 L</prefetch> implies a L</join> with the equivalent argument, and is
4132 properly merged with any existing L</join> specification. So the
4135 my $rs = $schema->resultset('CD')->search(
4136 {'record_label.name' => 'Music Product Ltd.'},
4138 join => {artist => 'record_label'},
4139 prefetch => 'artist',
4143 ... will work, searching on the record label's name, but only
4144 prefetching the C<artist>.
4146 =head3 Using L</prefetch> with L</select> / L</+select> / L</as> / L</+as>
4148 L</prefetch> implies a L</+select>/L</+as> with the fields of the
4149 prefetched relations. So given:
4151 my $rs = $schema->resultset('CD')->search(
4154 select => ['cd.title'],
4156 prefetch => 'artist',
4160 The L</select> becomes: C<'cd.title', 'artist.*'> and the L</as>
4161 becomes: C<'cd_title', 'artist.*'>.
4165 Prefetch does a lot of deep magic. As such, it may not behave exactly
4166 as you might expect.
4172 Prefetch uses the L</cache> to populate the prefetched relationships. This
4173 may or may not be what you want.
4177 If you specify a condition on a prefetched relationship, ONLY those
4178 rows that match the prefetched condition will be fetched into that relationship.
4179 This means that adding prefetch to a search() B<may alter> what is returned by
4180 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4182 my $artist_rs = $schema->resultset('Artist')->search({
4188 my $count = $artist_rs->first->cds->count;
4190 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4192 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4194 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4196 that cmp_ok() may or may not pass depending on the datasets involved. This
4197 behavior may or may not survive the 0.09 transition.
4205 =item Value: $source_alias
4209 Sets the source alias for the query. Normally, this defaults to C<me>, but
4210 nested search queries (sub-SELECTs) might need specific aliases set to
4211 reference inner queries. For example:
4214 ->related_resultset('CDs')
4215 ->related_resultset('Tracks')
4217 'track.id' => { -ident => 'none_search.id' },
4221 my $ids = $self->search({
4224 alias => 'none_search',
4225 group_by => 'none_search.id',
4226 })->get_column('id')->as_query;
4228 $self->search({ id => { -in => $ids } })
4230 This attribute is directly tied to L</current_source_alias>.
4240 Makes the resultset paged and specifies the page to retrieve. Effectively
4241 identical to creating a non-pages resultset and then calling ->page($page)
4244 If L</rows> attribute is not specified it defaults to 10 rows per page.
4246 When you have a paged resultset, L</count> will only return the number
4247 of rows in the page. To get the total, use the L</pager> and call
4248 C<total_entries> on it.
4258 Specifies the maximum number of rows for direct retrieval or the number of
4259 rows per page if the page attribute or method is used.
4265 =item Value: $offset
4269 Specifies the (zero-based) row number for the first row to be returned, or the
4270 of the first row of the first page if paging is used.
4272 =head2 software_limit
4276 =item Value: (0 | 1)
4280 When combined with L</rows> and/or L</offset> the generated SQL will not
4281 include any limit dialect stanzas. Instead the entire result will be selected
4282 as if no limits were specified, and DBIC will perform the limit locally, by
4283 artificially advancing and finishing the resulting L</cursor>.
4285 This is the recommended way of performing resultset limiting when no sane RDBMS
4286 implementation is available (e.g.
4287 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4288 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4294 =item Value: \@columns
4298 A arrayref of columns to group by. Can include columns of joined tables.
4300 group_by => [qw/ column1 column2 ... /]
4306 =item Value: $condition
4310 HAVING is a select statement attribute that is applied between GROUP BY and
4311 ORDER BY. It is applied to the after the grouping calculations have been
4314 having => { 'count_employee' => { '>=', 100 } }
4316 or with an in-place function in which case literal SQL is required:
4318 having => \[ 'count(employee) >= ?', [ count => 100 ] ]
4324 =item Value: (0 | 1)
4328 Set to 1 to group by all columns. If the resultset already has a group_by
4329 attribute, this setting is ignored and an appropriate warning is issued.
4335 Adds to the WHERE clause.
4337 # only return rows WHERE deleted IS NULL for all searches
4338 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4340 Can be overridden by passing C<< { where => undef } >> as an attribute
4343 For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
4349 Set to 1 to cache search results. This prevents extra SQL queries if you
4350 revisit rows in your ResultSet:
4352 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4354 while( my $artist = $resultset->next ) {
4358 $rs->first; # without cache, this would issue a query
4360 By default, searches are not cached.
4362 For more examples of using these attributes, see
4363 L<DBIx::Class::Manual::Cookbook>.
4369 =item Value: ( 'update' | 'shared' | \$scalar )
4373 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4374 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4377 =head1 DBIC BIND VALUES
4379 Because DBIC may need more information to bind values than just the column name
4380 and value itself, it uses a special format for both passing and receiving bind
4381 values. Each bind value should be composed of an arrayref of
4382 C<< [ \%args => $val ] >>. The format of C<< \%args >> is currently:
4388 If present (in any form), this is what is being passed directly to bind_param.
4389 Note that different DBD's expect different bind args. (e.g. DBD::SQLite takes
4390 a single numerical type, while DBD::Pg takes a hashref if bind options.)
4392 If this is specified, all other bind options described below are ignored.
4396 If present, this is used to infer the actual bind attribute by passing to
4397 C<< $resolved_storage->bind_attribute_by_data_type() >>. Defaults to the
4398 "data_type" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>.
4400 Note that the data type is somewhat freeform (hence the sqlt_ prefix);
4401 currently drivers are expected to "Do the Right Thing" when given a common
4402 datatype name. (Not ideal, but that's what we got at this point.)
4406 Currently used to correctly allocate buffers for bind_param_inout().
4407 Defaults to "size" from the L<add_columns column info|DBIx::Class::ResultSource/add_columns>,
4408 or to a sensible value based on the "data_type".
4412 Used to fill in missing sqlt_datatype and sqlt_size attributes (if they are
4413 explicitly specified they are never overriden). Also used by some weird DBDs,
4414 where the column name should be available at bind_param time (e.g. Oracle).
4418 For backwards compatibility and convenience, the following shortcuts are
4421 [ $name => $val ] === [ { dbic_colname => $name }, $val ]
4422 [ \$dt => $val ] === [ { sqlt_datatype => $dt }, $val ]
4423 [ undef, $val ] === [ {}, $val ]
4425 =head1 AUTHOR AND CONTRIBUTORS
4427 See L<AUTHOR|DBIx::Class/AUTHOR> and L<CONTRIBUTORS|DBIx::Class/CONTRIBUTORS> in DBIx::Class
4431 You may distribute this code under the same terms as Perl itself.