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
634 =item Arguments: $sql_fragment, @bind_values
636 =item Return Value: $resultset (scalar context) || @row_objs (list context)
640 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
641 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
643 Pass a literal chunk of SQL to be added to the conditional part of the
646 CAVEAT: C<search_literal> is provided for Class::DBI compatibility and should
647 only be used in that context. C<search_literal> is a convenience method.
648 It is equivalent to calling $schema->search(\[]), but if you want to ensure
649 columns are bound correctly, use C<search>.
651 Example of how to use C<search> instead of C<search_literal>
653 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
654 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
657 See L<DBIx::Class::Manual::Cookbook/Searching> and
658 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
659 require C<search_literal>.
664 my ($self, $sql, @bind) = @_;
666 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
669 return $self->search(\[ $sql, map [ __DUMMY__ => $_ ], @bind ], ($attr || () ));
676 =item Arguments: \%columns_values | @pk_values, \%attrs?
678 =item Return Value: $row_object | undef
682 Finds and returns a single row based on supplied criteria. Takes either a
683 hashref with the same format as L</create> (including inference of foreign
684 keys from related objects), or a list of primary key values in the same
685 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
686 declaration on the L</result_source>.
688 In either case an attempt is made to combine conditions already existing on
689 the resultset with the condition passed to this method.
691 To aid with preparing the correct query for the storage you may supply the
692 C<key> attribute, which is the name of a
693 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
694 unique constraint corresponding to the
695 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
696 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
697 to construct a query that satisfies the named unique constraint fully (
698 non-NULL values for each column member of the constraint) an exception is
701 If no C<key> is specified, the search is carried over all unique constraints
702 which are fully defined by the available condition.
704 If no such constraint is found, C<find> currently defaults to a simple
705 C<< search->(\%column_values) >> which may or may not do what you expect.
706 Note that this fallback behavior may be deprecated in further versions. If
707 you need to search with arbitrary conditions - use L</search>. If the query
708 resulting from this fallback produces more than one row, a warning to the
709 effect is issued, though only the first row is constructed and returned as
712 In addition to C<key>, L</find> recognizes and applies standard
713 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
715 Note that if you have extra concerns about the correctness of the resulting
716 query you need to specify the C<key> attribute and supply the entire condition
717 as an argument to find (since it is not always possible to perform the
718 combination of the resultset condition with the supplied one, especially if
719 the resultset condition contains literal sql).
721 For example, to find a row by its primary key:
723 my $cd = $schema->resultset('CD')->find(5);
725 You can also find a row by a specific unique constraint:
727 my $cd = $schema->resultset('CD')->find(
729 artist => 'Massive Attack',
730 title => 'Mezzanine',
732 { key => 'cd_artist_title' }
735 See also L</find_or_create> and L</update_or_create>.
741 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
743 my $rsrc = $self->result_source;
746 if (exists $attrs->{key}) {
747 $constraint_name = defined $attrs->{key}
749 : $self->throw_exception("An undefined 'key' resultset attribute makes no sense")
753 # Parse out the condition from input
756 if (ref $_[0] eq 'HASH') {
757 $call_cond = { %{$_[0]} };
760 # if only values are supplied we need to default to 'primary'
761 $constraint_name = 'primary' unless defined $constraint_name;
763 my @c_cols = $rsrc->unique_constraint_columns($constraint_name);
765 $self->throw_exception(
766 "No constraint columns, maybe a malformed '$constraint_name' constraint?"
769 $self->throw_exception (
770 'find() expects either a column/value hashref, or a list of values '
771 . "corresponding to the columns of the specified unique constraint '$constraint_name'"
772 ) unless @c_cols == @_;
775 @{$call_cond}{@c_cols} = @_;
779 for my $key (keys %$call_cond) {
781 my $keyref = ref($call_cond->{$key})
783 my $relinfo = $rsrc->relationship_info($key)
785 my $val = delete $call_cond->{$key};
787 next if $keyref eq 'ARRAY'; # has_many for multi_create
789 my $rel_q = $rsrc->_resolve_condition(
790 $relinfo->{cond}, $val, $key, $key
792 die "Can't handle complex relationship conditions in find" if ref($rel_q) ne 'HASH';
793 @related{keys %$rel_q} = values %$rel_q;
797 # relationship conditions take precedence (?)
798 @{$call_cond}{keys %related} = values %related;
800 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
802 if (defined $constraint_name) {
803 $final_cond = $self->_qualify_cond_columns (
805 $self->_build_unique_cond (
813 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
814 # This means that we got here after a merger of relationship conditions
815 # in ::Relationship::Base::search_related (the row method), and furthermore
816 # the relationship is of the 'single' type. This means that the condition
817 # provided by the relationship (already attached to $self) is sufficient,
818 # as there can be only one row in the database that would satisfy the
822 # no key was specified - fall down to heuristics mode:
823 # run through all unique queries registered on the resultset, and
824 # 'OR' all qualifying queries together
825 my (@unique_queries, %seen_column_combinations);
826 for my $c_name ($rsrc->unique_constraint_names) {
827 next if $seen_column_combinations{
828 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
831 push @unique_queries, try {
832 $self->_build_unique_cond ($c_name, $call_cond, 'croak_on_nulls')
836 $final_cond = @unique_queries
837 ? [ map { $self->_qualify_cond_columns($_, $alias) } @unique_queries ]
838 : $self->_non_unique_find_fallback ($call_cond, $attrs)
842 # Run the query, passing the result_class since it should propagate for find
843 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
844 if (keys %{$rs->_resolved_attrs->{collapse}}) {
846 carp "Query returned more than one row" if $rs->next;
854 # This is a stop-gap method as agreed during the discussion on find() cleanup:
855 # http://lists.scsys.co.uk/pipermail/dbix-class/2010-October/009535.html
857 # It is invoked when find() is called in legacy-mode with insufficiently-unique
858 # condition. It is provided for overrides until a saner way forward is devised
860 # *NOTE* This is not a public method, and it's *GUARANTEED* to disappear down
861 # the road. Please adjust your tests accordingly to catch this situation early
862 # DBIx::Class::ResultSet->can('_non_unique_find_fallback') is reasonable
864 # The method will not be removed without an adequately complete replacement
865 # for strict-mode enforcement
866 sub _non_unique_find_fallback {
867 my ($self, $cond, $attrs) = @_;
869 return $self->_qualify_cond_columns(
871 exists $attrs->{alias}
873 : $self->{attrs}{alias}
878 sub _qualify_cond_columns {
879 my ($self, $cond, $alias) = @_;
881 my %aliased = %$cond;
882 for (keys %aliased) {
883 $aliased{"$alias.$_"} = delete $aliased{$_}
890 sub _build_unique_cond {
891 my ($self, $constraint_name, $extra_cond, $croak_on_null) = @_;
893 my @c_cols = $self->result_source->unique_constraint_columns($constraint_name);
895 # combination may fail if $self->{cond} is non-trivial
896 my ($final_cond) = try {
897 $self->_merge_with_rscond ($extra_cond)
902 # trim out everything not in $columns
903 $final_cond = { map {
904 exists $final_cond->{$_}
905 ? ( $_ => $final_cond->{$_} )
909 if (my @missing = grep
910 { ! ($croak_on_null ? defined $final_cond->{$_} : exists $final_cond->{$_}) }
913 $self->throw_exception( sprintf ( "Unable to satisfy requested constraint '%s', no values for column(s): %s",
915 join (', ', map { "'$_'" } @missing),
922 !$ENV{DBIC_NULLABLE_KEY_NOWARN}
924 my @undefs = grep { ! defined $final_cond->{$_} } (keys %$final_cond)
926 carp_unique ( sprintf (
927 "NULL/undef values supplied for requested unique constraint '%s' (NULL "
928 . 'values in column(s): %s). This is almost certainly not what you wanted, '
929 . 'though you can set DBIC_NULLABLE_KEY_NOWARN to disable this warning.',
931 join (', ', map { "'$_'" } @undefs),
938 =head2 search_related
942 =item Arguments: $rel, $cond?, \%attrs?
944 =item Return Value: $new_resultset (scalar context) || @row_objs (list context)
948 $new_rs = $cd_rs->search_related('artist', {
952 Searches the specified relationship, optionally specifying a condition and
953 attributes for matching records. See L</ATTRIBUTES> for more information.
955 In list context, C<< ->all() >> is called implicitly on the resultset, thus
956 returning a list of row objects instead. To avoid that, use L</search_related_rs>.
958 See also L</search_related_rs>.
963 return shift->related_resultset(shift)->search(@_);
966 =head2 search_related_rs
968 This method works exactly the same as search_related, except that
969 it guarantees a resultset, even in list context.
973 sub search_related_rs {
974 return shift->related_resultset(shift)->search_rs(@_);
981 =item Arguments: none
983 =item Return Value: $cursor
987 Returns a storage-driven cursor to the given resultset. See
988 L<DBIx::Class::Cursor> for more information.
995 my $attrs = $self->_resolved_attrs_copy;
997 return $self->{cursor}
998 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
999 $attrs->{where},$attrs);
1006 =item Arguments: $cond?
1008 =item Return Value: $row_object | undef
1012 my $cd = $schema->resultset('CD')->single({ year => 2001 });
1014 Inflates the first result without creating a cursor if the resultset has
1015 any records in it; if not returns C<undef>. Used by L</find> as a lean version
1018 While this method can take an optional search condition (just like L</search>)
1019 being a fast-code-path it does not recognize search attributes. If you need to
1020 add extra joins or similar, call L</search> and then chain-call L</single> on the
1021 L<DBIx::Class::ResultSet> returned.
1027 As of 0.08100, this method enforces the assumption that the preceding
1028 query returns only one row. If more than one row is returned, you will receive
1031 Query returned more than one row
1033 In this case, you should be using L</next> or L</find> instead, or if you really
1034 know what you are doing, use the L</rows> attribute to explicitly limit the size
1037 This method will also throw an exception if it is called on a resultset prefetching
1038 has_many, as such a prefetch implies fetching multiple rows from the database in
1039 order to assemble the resulting object.
1046 my ($self, $where) = @_;
1048 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
1051 my $attrs = $self->_resolved_attrs_copy;
1053 if (keys %{$attrs->{collapse}}) {
1054 $self->throw_exception(
1055 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
1060 if (defined $attrs->{where}) {
1063 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
1064 $where, delete $attrs->{where} ]
1067 $attrs->{where} = $where;
1071 my @data = $self->result_source->storage->select_single(
1072 $attrs->{from}, $attrs->{select},
1073 $attrs->{where}, $attrs
1076 return (@data ? ($self->_construct_object(@data))[0] : undef);
1082 # Recursively collapse the query, accumulating values for each column.
1084 sub _collapse_query {
1085 my ($self, $query, $collapsed) = @_;
1089 if (ref $query eq 'ARRAY') {
1090 foreach my $subquery (@$query) {
1091 next unless ref $subquery; # -or
1092 $collapsed = $self->_collapse_query($subquery, $collapsed);
1095 elsif (ref $query eq 'HASH') {
1096 if (keys %$query and (keys %$query)[0] eq '-and') {
1097 foreach my $subquery (@{$query->{-and}}) {
1098 $collapsed = $self->_collapse_query($subquery, $collapsed);
1102 foreach my $col (keys %$query) {
1103 my $value = $query->{$col};
1104 $collapsed->{$col}{$value}++;
1116 =item Arguments: $cond?
1118 =item Return Value: $resultsetcolumn
1122 my $max_length = $rs->get_column('length')->max;
1124 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
1129 my ($self, $column) = @_;
1130 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
1138 =item Arguments: $cond, \%attrs?
1140 =item Return Value: $resultset (scalar context) || @row_objs (list context)
1144 # WHERE title LIKE '%blue%'
1145 $cd_rs = $rs->search_like({ title => '%blue%'});
1147 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
1148 that this is simply a convenience method retained for ex Class::DBI users.
1149 You most likely want to use L</search> with specific operators.
1151 For more information, see L<DBIx::Class::Manual::Cookbook>.
1153 This method is deprecated and will be removed in 0.09. Use L</search()>
1154 instead. An example conversion is:
1156 ->search_like({ foo => 'bar' });
1160 ->search({ foo => { like => 'bar' } });
1167 'search_like() is deprecated and will be removed in DBIC version 0.09.'
1168 .' Instead use ->search({ x => { -like => "y%" } })'
1169 .' (note the outer pair of {}s - they are important!)'
1171 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
1172 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
1173 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
1174 return $class->search($query, { %$attrs });
1181 =item Arguments: $first, $last
1183 =item Return Value: $resultset (scalar context) || @row_objs (list context)
1187 Returns a resultset or object list representing a subset of elements from the
1188 resultset slice is called on. Indexes are from 0, i.e., to get the first
1189 three records, call:
1191 my ($one, $two, $three) = $rs->slice(0, 2);
1196 my ($self, $min, $max) = @_;
1197 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
1198 $attrs->{offset} = $self->{attrs}{offset} || 0;
1199 $attrs->{offset} += $min;
1200 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
1201 return $self->search(undef, $attrs);
1202 #my $slice = (ref $self)->new($self->result_source, $attrs);
1203 #return (wantarray ? $slice->all : $slice);
1210 =item Arguments: none
1212 =item Return Value: $result | undef
1216 Returns the next element in the resultset (C<undef> is there is none).
1218 Can be used to efficiently iterate over records in the resultset:
1220 my $rs = $schema->resultset('CD')->search;
1221 while (my $cd = $rs->next) {
1225 Note that you need to store the resultset object, and call C<next> on it.
1226 Calling C<< resultset('Table')->next >> repeatedly will always return the
1227 first record from the resultset.
1233 if (my $cache = $self->get_cache) {
1234 $self->{all_cache_position} ||= 0;
1235 return $cache->[$self->{all_cache_position}++];
1237 if ($self->{attrs}{cache}) {
1238 delete $self->{pager};
1239 $self->{all_cache_position} = 1;
1240 return ($self->all)[0];
1242 if ($self->{stashed_objects}) {
1243 my $obj = shift(@{$self->{stashed_objects}});
1244 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
1248 exists $self->{stashed_row}
1249 ? @{delete $self->{stashed_row}}
1250 : $self->cursor->next
1252 return undef unless (@row);
1253 my ($row, @more) = $self->_construct_object(@row);
1254 $self->{stashed_objects} = \@more if @more;
1258 sub _construct_object {
1259 my ($self, @row) = @_;
1261 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row)
1263 my @new = $self->result_class->inflate_result($self->result_source, @$info);
1264 @new = $self->{_attrs}{record_filter}->(@new)
1265 if exists $self->{_attrs}{record_filter};
1269 sub _collapse_result {
1270 my ($self, $as_proto, $row) = @_;
1274 # 'foo' => [ undef, 'foo' ]
1275 # 'foo.bar' => [ 'foo', 'bar' ]
1276 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
1278 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
1280 my %collapse = %{$self->{_attrs}{collapse}||{}};
1284 # if we're doing collapsing (has_many prefetch) we need to grab records
1285 # until the PK changes, so fill @pri_index. if not, we leave it empty so
1286 # we know we don't have to bother.
1288 # the reason for not using the collapse stuff directly is because if you
1289 # had for e.g. two artists in a row with no cds, the collapse info for
1290 # both would be NULL (undef) so you'd lose the second artist
1292 # store just the index so we can check the array positions from the row
1293 # without having to contruct the full hash
1295 if (keys %collapse) {
1296 my %pri = map { ($_ => 1) } $self->result_source->_pri_cols;
1297 foreach my $i (0 .. $#construct_as) {
1298 next if defined($construct_as[$i][0]); # only self table
1299 if (delete $pri{$construct_as[$i][1]}) {
1300 push(@pri_index, $i);
1302 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
1306 # no need to do an if, it'll be empty if @pri_index is empty anyway
1308 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
1312 do { # no need to check anything at the front, we always want the first row
1316 foreach my $this_as (@construct_as) {
1317 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
1320 push(@const_rows, \%const);
1322 } until ( # no pri_index => no collapse => drop straight out
1325 do { # get another row, stash it, drop out if different PK
1327 @copy = $self->cursor->next;
1328 $self->{stashed_row} = \@copy;
1330 # last thing in do block, counts as true if anything doesn't match
1332 # check xor defined first for NULL vs. NOT NULL then if one is
1333 # defined the other must be so check string equality
1336 (defined $pri_vals{$_} ^ defined $copy[$_])
1337 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
1342 my $alias = $self->{attrs}{alias};
1349 foreach my $const (@const_rows) {
1350 scalar @const_keys or do {
1351 @const_keys = sort { length($a) <=> length($b) } keys %$const;
1353 foreach my $key (@const_keys) {
1356 my @parts = split(/\./, $key);
1358 my $data = $const->{$key};
1359 foreach my $p (@parts) {
1360 $target = $target->[1]->{$p} ||= [];
1362 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
1363 # collapsing at this point and on final part
1364 my $pos = $collapse_pos{$cur};
1365 CK: foreach my $ck (@ckey) {
1366 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
1367 $collapse_pos{$cur} = $data;
1368 delete @collapse_pos{ # clear all positioning for sub-entries
1369 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
1376 if (exists $collapse{$cur}) {
1377 $target = $target->[-1];
1380 $target->[0] = $data;
1382 $info->[0] = $const->{$key};
1390 =head2 result_source
1394 =item Arguments: $result_source?
1396 =item Return Value: $result_source
1400 An accessor for the primary ResultSource object from which this ResultSet
1407 =item Arguments: $result_class?
1409 =item Return Value: $result_class
1413 An accessor for the class to use when creating row objects. Defaults to
1414 C<< result_source->result_class >> - which in most cases is the name of the
1415 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1417 Note that changing the result_class will also remove any components
1418 that were originally loaded in the source class via
1419 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1420 in the original source class will not run.
1425 my ($self, $result_class) = @_;
1426 if ($result_class) {
1427 unless (ref $result_class) { # don't fire this for an object
1428 $self->ensure_class_loaded($result_class);
1430 $self->_result_class($result_class);
1431 # THIS LINE WOULD BE A BUG - this accessor specifically exists to
1432 # permit the user to set result class on one result set only; it only
1433 # chains if provided to search()
1434 #$self->{attrs}{result_class} = $result_class if ref $self;
1436 $self->_result_class;
1443 =item Arguments: $cond, \%attrs??
1445 =item Return Value: $count
1449 Performs an SQL C<COUNT> with the same query as the resultset was built
1450 with to find the number of elements. Passing arguments is equivalent to
1451 C<< $rs->search ($cond, \%attrs)->count >>
1457 return $self->search(@_)->count if @_ and defined $_[0];
1458 return scalar @{ $self->get_cache } if $self->get_cache;
1460 my $attrs = $self->_resolved_attrs_copy;
1462 # this is a little optimization - it is faster to do the limit
1463 # adjustments in software, instead of a subquery
1464 my $rows = delete $attrs->{rows};
1465 my $offset = delete $attrs->{offset};
1468 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1469 $crs = $self->_count_subq_rs ($attrs);
1472 $crs = $self->_count_rs ($attrs);
1474 my $count = $crs->next;
1476 $count -= $offset if $offset;
1477 $count = $rows if $rows and $rows < $count;
1478 $count = 0 if ($count < 0);
1487 =item Arguments: $cond, \%attrs??
1489 =item Return Value: $count_rs
1493 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1494 This can be very handy for subqueries:
1496 ->search( { amount => $some_rs->count_rs->as_query } )
1498 As with regular resultsets the SQL query will be executed only after
1499 the resultset is accessed via L</next> or L</all>. That would return
1500 the same single value obtainable via L</count>.
1506 return $self->search(@_)->count_rs if @_;
1508 # this may look like a lack of abstraction (count() does about the same)
1509 # but in fact an _rs *must* use a subquery for the limits, as the
1510 # software based limiting can not be ported if this $rs is to be used
1511 # in a subquery itself (i.e. ->as_query)
1512 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1513 return $self->_count_subq_rs;
1516 return $self->_count_rs;
1521 # returns a ResultSetColumn object tied to the count query
1524 my ($self, $attrs) = @_;
1526 my $rsrc = $self->result_source;
1527 $attrs ||= $self->_resolved_attrs;
1529 my $tmp_attrs = { %$attrs };
1530 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1531 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1533 # overwrite the selector (supplied by the storage)
1534 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $attrs);
1535 $tmp_attrs->{as} = 'count';
1536 delete @{$tmp_attrs}{qw/columns/};
1538 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1544 # same as above but uses a subquery
1546 sub _count_subq_rs {
1547 my ($self, $attrs) = @_;
1549 my $rsrc = $self->result_source;
1550 $attrs ||= $self->_resolved_attrs;
1552 my $sub_attrs = { %$attrs };
1553 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1554 delete @{$sub_attrs}{qw/collapse columns as select _prefetch_selector_range order_by for/};
1556 # if we multi-prefetch we group_by something unique, as this is what we would
1557 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1558 if ( keys %{$attrs->{collapse}} ) {
1559 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
1560 $rsrc->_identifying_column_set || $self->throw_exception(
1561 'Unable to construct a unique group_by criteria properly collapsing the '
1562 . 'has_many prefetch before count()'
1567 # Calculate subquery selector
1568 if (my $g = $sub_attrs->{group_by}) {
1570 my $sql_maker = $rsrc->storage->sql_maker;
1572 # necessary as the group_by may refer to aliased functions
1574 for my $sel (@{$attrs->{select}}) {
1575 $sel_index->{$sel->{-as}} = $sel
1576 if (ref $sel eq 'HASH' and $sel->{-as});
1579 # anything from the original select mentioned on the group-by needs to make it to the inner selector
1580 # also look for named aggregates referred in the having clause
1581 # having often contains scalarrefs - thus parse it out entirely
1583 if ($attrs->{having}) {
1584 local $sql_maker->{having_bind};
1585 local $sql_maker->{quote_char} = $sql_maker->{quote_char};
1586 local $sql_maker->{name_sep} = $sql_maker->{name_sep};
1587 unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
1588 $sql_maker->{quote_char} = [ "\x00", "\xFF" ];
1589 # if we don't unset it we screw up retarded but unfortunately working
1590 # 'MAX(foo.bar)' => { '>', 3 }
1591 $sql_maker->{name_sep} = '';
1594 my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
1596 my $sql = $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} });
1598 # search for both a proper quoted qualified string, for a naive unquoted scalarref
1599 # and if all fails for an utterly naive quoted scalar-with-function
1601 $rquote $sep $lquote (.+?) $rquote
1603 [\s,] \w+ \. (\w+) [\s,]
1605 [\s,] $lquote (.+?) $rquote [\s,]
1607 push @parts, ($1 || $2 || $3); # one of them matched if we got here
1612 my $colpiece = $sel_index->{$_} || $_;
1614 # unqualify join-based group_by's. Arcane but possible query
1615 # also horrible horrible hack to alias a column (not a func.)
1616 # (probably need to introduce SQLA syntax)
1617 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1620 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1622 push @{$sub_attrs->{select}}, $colpiece;
1626 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1627 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1630 return $rsrc->resultset_class
1631 ->new ($rsrc, $sub_attrs)
1633 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1634 ->get_column ('count');
1641 =head2 count_literal
1645 =item Arguments: $sql_fragment, @bind_values
1647 =item Return Value: $count
1651 Counts the results in a literal query. Equivalent to calling L</search_literal>
1652 with the passed arguments, then L</count>.
1656 sub count_literal { shift->search_literal(@_)->count; }
1662 =item Arguments: none
1664 =item Return Value: @objects
1668 Returns all elements in the resultset.
1675 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1678 return @{ $self->get_cache } if $self->get_cache;
1682 if (keys %{$self->_resolved_attrs->{collapse}}) {
1683 # Using $self->cursor->all is really just an optimisation.
1684 # If we're collapsing has_many prefetches it probably makes
1685 # very little difference, and this is cleaner than hacking
1686 # _construct_object to survive the approach
1687 $self->cursor->reset;
1688 my @row = $self->cursor->next;
1690 push(@obj, $self->_construct_object(@row));
1691 @row = (exists $self->{stashed_row}
1692 ? @{delete $self->{stashed_row}}
1693 : $self->cursor->next);
1696 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1699 $self->set_cache(\@obj) if $self->{attrs}{cache};
1708 =item Arguments: none
1710 =item Return Value: $self
1714 Resets the resultset's cursor, so you can iterate through the elements again.
1715 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1722 delete $self->{_attrs} if exists $self->{_attrs};
1723 $self->{all_cache_position} = 0;
1724 $self->cursor->reset;
1732 =item Arguments: none
1734 =item Return Value: $object | undef
1738 Resets the resultset and returns an object for the first result (or C<undef>
1739 if the resultset is empty).
1744 return $_[0]->reset->next;
1750 # Determines whether and what type of subquery is required for the $rs operation.
1751 # If grouping is necessary either supplies its own, or verifies the current one
1752 # After all is done delegates to the proper storage method.
1754 sub _rs_update_delete {
1755 my ($self, $op, $values) = @_;
1757 my $cond = $self->{cond};
1758 my $rsrc = $self->result_source;
1759 my $storage = $rsrc->schema->storage;
1761 my $attrs = { %{$self->_resolved_attrs} };
1763 my $existing_group_by = delete $attrs->{group_by};
1764 my $needs_subq = defined $existing_group_by;
1766 # simplify the joinmap and maybe decide if a subquery is necessary
1767 my $relation_classifications = {};
1769 if (ref($attrs->{from}) eq 'ARRAY') {
1770 # if we already know we need a subq, no point of classifying relations
1771 if (!$needs_subq and @{$attrs->{from}} > 1) {
1772 $attrs->{from} = $storage->_prune_unused_joins ($attrs->{from}, $attrs->{select}, $cond, $attrs);
1774 $relation_classifications = $storage->_resolve_aliastypes_from_select_args (
1775 [ @{$attrs->{from}}[1 .. $#{$attrs->{from}}] ],
1783 $needs_subq ||= 1; # if {from} is unparseable assume the worst
1786 # do we need anything like a subquery?
1790 ! keys %{ $relation_classifications->{restricting} || {} }
1792 ! $self->_has_resolved_attr(qw/rows offset/) # limits call for a subq
1794 # Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
1795 # a condition containing 'me' or other table prefixes will not work
1796 # at all. Tell SQLMaker to dequalify idents via a gross hack.
1798 my $sqla = $rsrc->storage->sql_maker;
1799 local $sqla->{_dequalify_idents} = 1;
1800 \[ $sqla->_recurse_where($self->{cond}) ];
1802 return $rsrc->storage->$op(
1804 $op eq 'update' ? $values : (),
1809 # we got this far - means it is time to wrap a subquery
1810 my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
1812 "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
1818 # make a new $rs selecting only the PKs (that's all we really need for the subq)
1819 delete $attrs->{$_} for qw/collapse _collapse_order_by select _prefetch_selector_range as/;
1820 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
1821 $attrs->{group_by} = \ ''; # FIXME - this is an evil hack, it causes the optimiser to kick in and throw away the LEFT joins
1822 my $subrs = (ref $self)->new($rsrc, $attrs);
1824 if (@$idcols == 1) {
1825 return $storage->$op (
1827 $op eq 'update' ? $values : (),
1828 { $idcols->[0] => { -in => $subrs->as_query } },
1831 elsif ($storage->_use_multicolumn_in) {
1832 # This is hideously ugly, but SQLA does not understand multicol IN expressions
1833 my $sql_maker = $storage->sql_maker;
1834 my ($sql, @bind) = @${$subrs->as_query};
1835 $sql = sprintf ('(%s) IN %s', # the as_query already comes with a set of parenthesis
1836 join (', ', map { $sql_maker->_quote ($_) } @$idcols),
1840 return $storage->$op (
1842 $op eq 'update' ? $values : (),
1848 # if all else fails - get all primary keys and operate over a ORed set
1849 # wrap in a transaction for consistency
1850 # this is where the group_by starts to matter
1854 keys %{ $relation_classifications->{multiplying} || {} }
1856 # make sure if there is a supplied group_by it matches the columns compiled above
1857 # perfectly. Anything else can not be sanely executed on most databases so croak
1858 # right then and there
1859 if ($existing_group_by) {
1860 my @current_group_by = map
1861 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1866 join ("\x00", sort @current_group_by)
1868 join ("\x00", sort @{$attrs->{columns}} )
1870 $self->throw_exception (
1871 "You have just attempted a $op operation on a resultset which does group_by"
1872 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1873 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1874 . ' kind of queries. Please retry the operation with a modified group_by or'
1875 . ' without using one at all.'
1880 $subrs = $subrs->search({}, { group_by => $attrs->{columns} });
1883 my $guard = $storage->txn_scope_guard;
1886 for my $row ($subrs->cursor->all) {
1887 push @op_condition, { map
1888 { $idcols->[$_] => $row->[$_] }
1893 my $res = $storage->$op (
1895 $op eq 'update' ? $values : (),
1909 =item Arguments: \%values
1911 =item Return Value: $storage_rv
1915 Sets the specified columns in the resultset to the supplied values in a
1916 single query. Note that this will not run any accessor/set_column/update
1917 triggers, nor will it update any row object instances derived from this
1918 resultset (this includes the contents of the L<resultset cache|/set_cache>
1919 if any). See L</update_all> if you need to execute any on-update
1920 triggers or cascades defined either by you or a
1921 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1923 The return value is a pass through of what the underlying
1924 storage backend returned, and may vary. See L<DBI/execute> for the most
1929 Note that L</update> does not process/deflate any of the values passed in.
1930 This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
1931 ensure manually that any value passed to this method will stringify to
1932 something the RDBMS knows how to deal with. A notable example is the
1933 handling of L<DateTime> objects, for more info see:
1934 L<DBIx::Class::Manual::Cookbook/Formatting DateTime objects in queries>.
1939 my ($self, $values) = @_;
1940 $self->throw_exception('Values for update must be a hash')
1941 unless ref $values eq 'HASH';
1943 return $self->_rs_update_delete ('update', $values);
1950 =item Arguments: \%values
1952 =item Return Value: 1
1956 Fetches all objects and updates them one at a time via
1957 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
1958 triggers, while L</update> will not.
1963 my ($self, $values) = @_;
1964 $self->throw_exception('Values for update_all must be a hash')
1965 unless ref $values eq 'HASH';
1967 my $guard = $self->result_source->schema->txn_scope_guard;
1968 $_->update({%$values}) for $self->all; # shallow copy - update will mangle it
1977 =item Arguments: none
1979 =item Return Value: $storage_rv
1983 Deletes the rows matching this resultset in a single query. Note that this
1984 will not run any delete triggers, nor will it alter the
1985 L<in_storage|DBIx::Class::Row/in_storage> status of any row object instances
1986 derived from this resultset (this includes the contents of the
1987 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
1988 execute any on-delete triggers or cascades defined either by you or a
1989 L<result component|DBIx::Class::Manual::Component/WHAT IS A COMPONENT>.
1991 The return value is a pass through of what the underlying storage backend
1992 returned, and may vary. See L<DBI/execute> for the most common case.
1998 $self->throw_exception('delete does not accept any arguments')
2001 return $self->_rs_update_delete ('delete');
2008 =item Arguments: none
2010 =item Return Value: 1
2014 Fetches all objects and deletes them one at a time via
2015 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
2016 triggers, while L</delete> will not.
2022 $self->throw_exception('delete_all does not accept any arguments')
2025 my $guard = $self->result_source->schema->txn_scope_guard;
2026 $_->delete for $self->all;
2035 =item Arguments: \@data;
2039 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
2040 For the arrayref of hashrefs style each hashref should be a structure suitable
2041 for submitting to a $resultset->create(...) method.
2043 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
2044 to insert the data, as this is a faster method.
2046 Otherwise, each set of data is inserted into the database using
2047 L<DBIx::Class::ResultSet/create>, and the resulting objects are
2048 accumulated into an array. The array itself, or an array reference
2049 is returned depending on scalar or list context.
2051 Example: Assuming an Artist Class that has many CDs Classes relating:
2053 my $Artist_rs = $schema->resultset("Artist");
2055 ## Void Context Example
2056 $Artist_rs->populate([
2057 { artistid => 4, name => 'Manufactured Crap', cds => [
2058 { title => 'My First CD', year => 2006 },
2059 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2062 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
2063 { title => 'My parents sold me to a record company', year => 2005 },
2064 { title => 'Why Am I So Ugly?', year => 2006 },
2065 { title => 'I Got Surgery and am now Popular', year => 2007 }
2070 ## Array Context Example
2071 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
2072 { name => "Artist One"},
2073 { name => "Artist Two"},
2074 { name => "Artist Three", cds=> [
2075 { title => "First CD", year => 2007},
2076 { title => "Second CD", year => 2008},
2080 print $ArtistOne->name; ## response is 'Artist One'
2081 print $ArtistThree->cds->count ## reponse is '2'
2083 For the arrayref of arrayrefs style, the first element should be a list of the
2084 fieldsnames to which the remaining elements are rows being inserted. For
2087 $Arstist_rs->populate([
2088 [qw/artistid name/],
2089 [100, 'A Formally Unknown Singer'],
2090 [101, 'A singer that jumped the shark two albums ago'],
2091 [102, 'An actually cool singer'],
2094 Please note an important effect on your data when choosing between void and
2095 wantarray context. Since void context goes straight to C<insert_bulk> in
2096 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
2097 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
2098 create primary keys for you, you will find that your PKs are empty. In this
2099 case you will have to use the wantarray context in order to create those
2107 # cruft placed in standalone method
2108 my $data = $self->_normalize_populate_args(@_);
2110 return unless @$data;
2112 if(defined wantarray) {
2114 foreach my $item (@$data) {
2115 push(@created, $self->create($item));
2117 return wantarray ? @created : \@created;
2120 my $first = $data->[0];
2122 # if a column is a registered relationship, and is a non-blessed hash/array, consider
2123 # it relationship data
2124 my (@rels, @columns);
2125 my $rsrc = $self->result_source;
2126 my $rels = { map { $_ => $rsrc->relationship_info($_) } $rsrc->relationships };
2127 for (keys %$first) {
2128 my $ref = ref $first->{$_};
2129 $rels->{$_} && ($ref eq 'ARRAY' or $ref eq 'HASH')
2135 my @pks = $rsrc->primary_columns;
2137 ## do the belongs_to relationships
2138 foreach my $index (0..$#$data) {
2140 # delegate to create() for any dataset without primary keys with specified relationships
2141 if (grep { !defined $data->[$index]->{$_} } @pks ) {
2143 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
2144 my @ret = $self->populate($data);
2150 foreach my $rel (@rels) {
2151 next unless ref $data->[$index]->{$rel} eq "HASH";
2152 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
2153 my ($reverse_relname, $reverse_relinfo) = %{$rsrc->reverse_relationship_info($rel)};
2154 my $related = $result->result_source->_resolve_condition(
2155 $reverse_relinfo->{cond},
2161 delete $data->[$index]->{$rel};
2162 $data->[$index] = {%{$data->[$index]}, %$related};
2164 push @columns, keys %$related if $index == 0;
2168 ## inherit the data locked in the conditions of the resultset
2169 my ($rs_data) = $self->_merge_with_rscond({});
2170 delete @{$rs_data}{@columns};
2171 my @inherit_cols = keys %$rs_data;
2172 my @inherit_data = values %$rs_data;
2174 ## do bulk insert on current row
2175 $rsrc->storage->insert_bulk(
2177 [@columns, @inherit_cols],
2178 [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
2181 ## do the has_many relationships
2182 foreach my $item (@$data) {
2186 foreach my $rel (@rels) {
2187 next unless ref $item->{$rel} eq "ARRAY" && @{ $item->{$rel} };
2189 $main_row ||= $self->new_result({map { $_ => $item->{$_} } @pks});
2191 my $child = $main_row->$rel;
2193 my $related = $child->result_source->_resolve_condition(
2194 $rels->{$rel}{cond},
2200 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
2201 my @populate = map { {%$_, %$related} } @rows_to_add;
2203 $child->populate( \@populate );
2210 # populate() argumnets went over several incarnations
2211 # What we ultimately support is AoH
2212 sub _normalize_populate_args {
2213 my ($self, $arg) = @_;
2215 if (ref $arg eq 'ARRAY') {
2219 elsif (ref $arg->[0] eq 'HASH') {
2222 elsif (ref $arg->[0] eq 'ARRAY') {
2224 my @colnames = @{$arg->[0]};
2225 foreach my $values (@{$arg}[1 .. $#$arg]) {
2226 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
2232 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
2239 =item Arguments: none
2241 =item Return Value: $pager
2245 Return Value a L<Data::Page> object for the current resultset. Only makes
2246 sense for queries with a C<page> attribute.
2248 To get the full count of entries for a paged resultset, call
2249 C<total_entries> on the L<Data::Page> object.
2256 return $self->{pager} if $self->{pager};
2258 my $attrs = $self->{attrs};
2259 if (!defined $attrs->{page}) {
2260 $self->throw_exception("Can't create pager for non-paged rs");
2262 elsif ($attrs->{page} <= 0) {
2263 $self->throw_exception('Invalid page number (page-numbers are 1-based)');
2265 $attrs->{rows} ||= 10;
2267 # throw away the paging flags and re-run the count (possibly
2268 # with a subselect) to get the real total count
2269 my $count_attrs = { %$attrs };
2270 delete $count_attrs->{$_} for qw/rows offset page pager/;
2272 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
2274 require DBIx::Class::ResultSet::Pager;
2275 return $self->{pager} = DBIx::Class::ResultSet::Pager->new(
2276 sub { $total_rs->count }, #lazy-get the total
2278 $self->{attrs}{page},
2286 =item Arguments: $page_number
2288 =item Return Value: $rs
2292 Returns a resultset for the $page_number page of the resultset on which page
2293 is called, where each page contains a number of rows equal to the 'rows'
2294 attribute set on the resultset (10 by default).
2299 my ($self, $page) = @_;
2300 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2307 =item Arguments: \%vals
2309 =item Return Value: $rowobject
2313 Creates a new row object in the resultset's result class and returns
2314 it. The row is not inserted into the database at this point, call
2315 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2316 will tell you whether the row object has been inserted or not.
2318 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2323 my ($self, $values) = @_;
2325 $self->throw_exception( "new_result takes only one argument - a hashref of values" )
2328 $self->throw_exception( "new_result expects a hashref" )
2329 unless (ref $values eq 'HASH');
2331 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2335 @$cols_from_relations
2336 ? (-cols_from_relations => $cols_from_relations)
2338 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2341 return $self->result_class->new(\%new);
2344 # _merge_with_rscond
2346 # Takes a simple hash of K/V data and returns its copy merged with the
2347 # condition already present on the resultset. Additionally returns an
2348 # arrayref of value/condition names, which were inferred from related
2349 # objects (this is needed for in-memory related objects)
2350 sub _merge_with_rscond {
2351 my ($self, $data) = @_;
2353 my (%new_data, @cols_from_relations);
2355 my $alias = $self->{attrs}{alias};
2357 if (! defined $self->{cond}) {
2358 # just massage $data below
2360 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
2361 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
2362 @cols_from_relations = keys %new_data;
2364 elsif (ref $self->{cond} ne 'HASH') {
2365 $self->throw_exception(
2366 "Can't abstract implicit construct, resultset condition not a hash"
2370 # precendence must be given to passed values over values inherited from
2371 # the cond, so the order here is important.
2372 my $collapsed_cond = $self->_collapse_cond($self->{cond});
2373 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
2375 while ( my($col, $value) = each %implied ) {
2376 my $vref = ref $value;
2382 (keys %$value)[0] eq '='
2384 $new_data{$col} = $value->{'='};
2386 elsif( !$vref or $vref eq 'SCALAR' or blessed($value) ) {
2387 $new_data{$col} = $value;
2394 %{ $self->_remove_alias($data, $alias) },
2397 return (\%new_data, \@cols_from_relations);
2400 # _has_resolved_attr
2402 # determines if the resultset defines at least one
2403 # of the attributes supplied
2405 # used to determine if a subquery is neccessary
2407 # supports some virtual attributes:
2409 # This will scan for any joins being present on the resultset.
2410 # It is not a mere key-search but a deep inspection of {from}
2413 sub _has_resolved_attr {
2414 my ($self, @attr_names) = @_;
2416 my $attrs = $self->_resolved_attrs;
2420 for my $n (@attr_names) {
2421 if (grep { $n eq $_ } (qw/-join/) ) {
2422 $extra_checks{$n}++;
2426 my $attr = $attrs->{$n};
2428 next if not defined $attr;
2430 if (ref $attr eq 'HASH') {
2431 return 1 if keys %$attr;
2433 elsif (ref $attr eq 'ARRAY') {
2441 # a resolved join is expressed as a multi-level from
2443 $extra_checks{-join}
2445 ref $attrs->{from} eq 'ARRAY'
2447 @{$attrs->{from}} > 1
2455 # Recursively collapse the condition.
2457 sub _collapse_cond {
2458 my ($self, $cond, $collapsed) = @_;
2462 if (ref $cond eq 'ARRAY') {
2463 foreach my $subcond (@$cond) {
2464 next unless ref $subcond; # -or
2465 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2468 elsif (ref $cond eq 'HASH') {
2469 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2470 foreach my $subcond (@{$cond->{-and}}) {
2471 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2475 foreach my $col (keys %$cond) {
2476 my $value = $cond->{$col};
2477 $collapsed->{$col} = $value;
2487 # Remove the specified alias from the specified query hash. A copy is made so
2488 # the original query is not modified.
2491 my ($self, $query, $alias) = @_;
2493 my %orig = %{ $query || {} };
2496 foreach my $key (keys %orig) {
2498 $unaliased{$key} = $orig{$key};
2501 $unaliased{$1} = $orig{$key}
2502 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2512 =item Arguments: none
2514 =item Return Value: \[ $sql, @bind ]
2518 Returns the SQL query and bind vars associated with the invocant.
2520 This is generally used as the RHS for a subquery.
2527 my $attrs = $self->_resolved_attrs_copy;
2532 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2533 # $sql also has no wrapping parenthesis in list ctx
2535 my $sqlbind = $self->result_source->storage
2536 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2545 =item Arguments: \%vals, \%attrs?
2547 =item Return Value: $rowobject
2551 my $artist = $schema->resultset('Artist')->find_or_new(
2552 { artist => 'fred' }, { key => 'artists' });
2554 $cd->cd_to_producer->find_or_new({ producer => $producer },
2555 { key => 'primary });
2557 Find an existing record from this resultset using L</find>. if none exists,
2558 instantiate a new result object and return it. The object will not be saved
2559 into your storage until you call L<DBIx::Class::Row/insert> on it.
2561 You most likely want this method when looking for existing rows using a unique
2562 constraint that is not the primary key, or looking for related rows.
2564 If you want objects to be saved immediately, use L</find_or_create> instead.
2566 B<Note>: Make sure to read the documentation of L</find> and understand the
2567 significance of the C<key> attribute, as its lack may skew your search, and
2568 subsequently result in spurious new objects.
2570 B<Note>: Take care when using C<find_or_new> with a table having
2571 columns with default values that you intend to be automatically
2572 supplied by the database (e.g. an auto_increment primary key column).
2573 In normal usage, the value of such columns should NOT be included at
2574 all in the call to C<find_or_new>, even when set to C<undef>.
2580 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2581 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2582 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2585 return $self->new_result($hash);
2592 =item Arguments: \%vals
2594 =item Return Value: a L<DBIx::Class::Row> $object
2598 Attempt to create a single new row or a row with multiple related rows
2599 in the table represented by the resultset (and related tables). This
2600 will not check for duplicate rows before inserting, use
2601 L</find_or_create> to do that.
2603 To create one row for this resultset, pass a hashref of key/value
2604 pairs representing the columns of the table and the values you wish to
2605 store. If the appropriate relationships are set up, foreign key fields
2606 can also be passed an object representing the foreign row, and the
2607 value will be set to its primary key.
2609 To create related objects, pass a hashref of related-object column values
2610 B<keyed on the relationship name>. If the relationship is of type C<multi>
2611 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2612 The process will correctly identify columns holding foreign keys, and will
2613 transparently populate them from the keys of the corresponding relation.
2614 This can be applied recursively, and will work correctly for a structure
2615 with an arbitrary depth and width, as long as the relationships actually
2616 exists and the correct column data has been supplied.
2618 Instead of hashrefs of plain related data (key/value pairs), you may
2619 also pass new or inserted objects. New objects (not inserted yet, see
2620 L</new>), will be inserted into their appropriate tables.
2622 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2624 Example of creating a new row.
2626 $person_rs->create({
2627 name=>"Some Person",
2628 email=>"somebody@someplace.com"
2631 Example of creating a new row and also creating rows in a related C<has_many>
2632 or C<has_one> resultset. Note Arrayref.
2635 { artistid => 4, name => 'Manufactured Crap', cds => [
2636 { title => 'My First CD', year => 2006 },
2637 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2642 Example of creating a new row and also creating a row in a related
2643 C<belongs_to> resultset. Note Hashref.
2646 title=>"Music for Silly Walks",
2649 name=>"Silly Musician",
2657 When subclassing ResultSet never attempt to override this method. Since
2658 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2659 lot of the internals simply never call it, so your override will be
2660 bypassed more often than not. Override either L<new|DBIx::Class::Row/new>
2661 or L<insert|DBIx::Class::Row/insert> depending on how early in the
2662 L</create> process you need to intervene. See also warning pertaining to
2670 my ($self, $attrs) = @_;
2671 $self->throw_exception( "create needs a hashref" )
2672 unless ref $attrs eq 'HASH';
2673 return $self->new_result($attrs)->insert;
2676 =head2 find_or_create
2680 =item Arguments: \%vals, \%attrs?
2682 =item Return Value: $rowobject
2686 $cd->cd_to_producer->find_or_create({ producer => $producer },
2687 { key => 'primary' });
2689 Tries to find a record based on its primary key or unique constraints; if none
2690 is found, creates one and returns that instead.
2692 my $cd = $schema->resultset('CD')->find_or_create({
2694 artist => 'Massive Attack',
2695 title => 'Mezzanine',
2699 Also takes an optional C<key> attribute, to search by a specific key or unique
2700 constraint. For example:
2702 my $cd = $schema->resultset('CD')->find_or_create(
2704 artist => 'Massive Attack',
2705 title => 'Mezzanine',
2707 { key => 'cd_artist_title' }
2710 B<Note>: Make sure to read the documentation of L</find> and understand the
2711 significance of the C<key> attribute, as its lack may skew your search, and
2712 subsequently result in spurious row creation.
2714 B<Note>: Because find_or_create() reads from the database and then
2715 possibly inserts based on the result, this method is subject to a race
2716 condition. Another process could create a record in the table after
2717 the find has completed and before the create has started. To avoid
2718 this problem, use find_or_create() inside a transaction.
2720 B<Note>: Take care when using C<find_or_create> with a table having
2721 columns with default values that you intend to be automatically
2722 supplied by the database (e.g. an auto_increment primary key column).
2723 In normal usage, the value of such columns should NOT be included at
2724 all in the call to C<find_or_create>, even when set to C<undef>.
2726 See also L</find> and L</update_or_create>. For information on how to declare
2727 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2729 If you need to know if an existing row was found or a new one created use
2730 L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2731 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2734 my $cd = $schema->resultset('CD')->find_or_new({
2736 artist => 'Massive Attack',
2737 title => 'Mezzanine',
2741 if( !$cd->in_storage ) {
2748 sub find_or_create {
2750 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2751 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2752 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2755 return $self->create($hash);
2758 =head2 update_or_create
2762 =item Arguments: \%col_values, { key => $unique_constraint }?
2764 =item Return Value: $row_object
2768 $resultset->update_or_create({ col => $val, ... });
2770 Like L</find_or_create>, but if a row is found it is immediately updated via
2771 C<< $found_row->update (\%col_values) >>.
2774 Takes an optional C<key> attribute to search on a specific unique constraint.
2777 # In your application
2778 my $cd = $schema->resultset('CD')->update_or_create(
2780 artist => 'Massive Attack',
2781 title => 'Mezzanine',
2784 { key => 'cd_artist_title' }
2787 $cd->cd_to_producer->update_or_create({
2788 producer => $producer,
2794 B<Note>: Make sure to read the documentation of L</find> and understand the
2795 significance of the C<key> attribute, as its lack may skew your search, and
2796 subsequently result in spurious row creation.
2798 B<Note>: Take care when using C<update_or_create> with a table having
2799 columns with default values that you intend to be automatically
2800 supplied by the database (e.g. an auto_increment primary key column).
2801 In normal usage, the value of such columns should NOT be included at
2802 all in the call to C<update_or_create>, even when set to C<undef>.
2804 See also L</find> and L</find_or_create>. For information on how to declare
2805 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2807 If you need to know if an existing row was updated or a new one created use
2808 L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
2809 to call L<DBIx::Class::Row/insert> to save the newly created row to the
2814 sub update_or_create {
2816 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2817 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2819 my $row = $self->find($cond, $attrs);
2821 $row->update($cond);
2825 return $self->create($cond);
2828 =head2 update_or_new
2832 =item Arguments: \%col_values, { key => $unique_constraint }?
2834 =item Return Value: $rowobject
2838 $resultset->update_or_new({ col => $val, ... });
2840 Like L</find_or_new> but if a row is found it is immediately updated via
2841 C<< $found_row->update (\%col_values) >>.
2845 # In your application
2846 my $cd = $schema->resultset('CD')->update_or_new(
2848 artist => 'Massive Attack',
2849 title => 'Mezzanine',
2852 { key => 'cd_artist_title' }
2855 if ($cd->in_storage) {
2856 # the cd was updated
2859 # the cd is not yet in the database, let's insert it
2863 B<Note>: Make sure to read the documentation of L</find> and understand the
2864 significance of the C<key> attribute, as its lack may skew your search, and
2865 subsequently result in spurious new objects.
2867 B<Note>: Take care when using C<update_or_new> with a table having
2868 columns with default values that you intend to be automatically
2869 supplied by the database (e.g. an auto_increment primary key column).
2870 In normal usage, the value of such columns should NOT be included at
2871 all in the call to C<update_or_new>, even when set to C<undef>.
2873 See also L</find>, L</find_or_create> and L</find_or_new>.
2879 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2880 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2882 my $row = $self->find( $cond, $attrs );
2883 if ( defined $row ) {
2884 $row->update($cond);
2888 return $self->new_result($cond);
2895 =item Arguments: none
2897 =item Return Value: \@cache_objects | undef
2901 Gets the contents of the cache for the resultset, if the cache is set.
2903 The cache is populated either by using the L</prefetch> attribute to
2904 L</search> or by calling L</set_cache>.
2916 =item Arguments: \@cache_objects
2918 =item Return Value: \@cache_objects
2922 Sets the contents of the cache for the resultset. Expects an arrayref
2923 of objects of the same class as those produced by the resultset. Note that
2924 if the cache is set the resultset will return the cached objects rather
2925 than re-querying the database even if the cache attr is not set.
2927 The contents of the cache can also be populated by using the
2928 L</prefetch> attribute to L</search>.
2933 my ( $self, $data ) = @_;
2934 $self->throw_exception("set_cache requires an arrayref")
2935 if defined($data) && (ref $data ne 'ARRAY');
2936 $self->{all_cache} = $data;
2943 =item Arguments: none
2945 =item Return Value: undef
2949 Clears the cache for the resultset.
2954 shift->set_cache(undef);
2961 =item Arguments: none
2963 =item Return Value: true, if the resultset has been paginated
2971 return !!$self->{attrs}{page};
2978 =item Arguments: none
2980 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2988 return scalar $self->result_source->storage->_extract_order_criteria($self->{attrs}{order_by});
2991 =head2 related_resultset
2995 =item Arguments: $relationship_name
2997 =item Return Value: $resultset
3001 Returns a related resultset for the supplied relationship name.
3003 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
3007 sub related_resultset {
3008 my ($self, $rel) = @_;
3010 $self->{related_resultsets} ||= {};
3011 return $self->{related_resultsets}{$rel} ||= do {
3012 my $rsrc = $self->result_source;
3013 my $rel_info = $rsrc->relationship_info($rel);
3015 $self->throw_exception(
3016 "search_related: result source '" . $rsrc->source_name .
3017 "' has no such relationship $rel")
3020 my $attrs = $self->_chain_relationship($rel);
3022 my $join_count = $attrs->{seen_join}{$rel};
3024 my $alias = $self->result_source->storage
3025 ->relname_to_table_alias($rel, $join_count);
3027 # since this is search_related, and we already slid the select window inwards
3028 # (the select/as attrs were deleted in the beginning), we need to flip all
3029 # left joins to inner, so we get the expected results
3030 # read the comment on top of the actual function to see what this does
3031 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
3034 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
3035 delete @{$attrs}{qw(result_class alias)};
3039 if (my $cache = $self->get_cache) {
3040 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
3041 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
3046 my $rel_source = $rsrc->related_source($rel);
3050 # The reason we do this now instead of passing the alias to the
3051 # search_rs below is that if you wrap/overload resultset on the
3052 # source you need to know what alias it's -going- to have for things
3053 # to work sanely (e.g. RestrictWithObject wants to be able to add
3054 # extra query restrictions, and these may need to be $alias.)
3056 my $rel_attrs = $rel_source->resultset_attributes;
3057 local $rel_attrs->{alias} = $alias;
3059 $rel_source->resultset
3063 where => $attrs->{where},
3066 $new->set_cache($new_cache) if $new_cache;
3071 =head2 current_source_alias
3075 =item Arguments: none
3077 =item Return Value: $source_alias
3081 Returns the current table alias for the result source this resultset is built
3082 on, that will be used in the SQL query. Usually it is C<me>.
3084 Currently the source alias that refers to the result set returned by a
3085 L</search>/L</find> family method depends on how you got to the resultset: it's
3086 C<me> by default, but eg. L</search_related> aliases it to the related result
3087 source name (and keeps C<me> referring to the original result set). The long
3088 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
3089 (and make this method unnecessary).
3091 Thus it's currently necessary to use this method in predefined queries (see
3092 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
3093 source alias of the current result set:
3095 # in a result set class
3097 my ($self, $user) = @_;
3099 my $me = $self->current_source_alias;
3101 return $self->search({
3102 "$me.modified" => $user->id,
3108 sub current_source_alias {
3111 return ($self->{attrs} || {})->{alias} || 'me';
3114 =head2 as_subselect_rs
3118 =item Arguments: none
3120 =item Return Value: $resultset
3124 Act as a barrier to SQL symbols. The resultset provided will be made into a
3125 "virtual view" by including it as a subquery within the from clause. From this
3126 point on, any joined tables are inaccessible to ->search on the resultset (as if
3127 it were simply where-filtered without joins). For example:
3129 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
3131 # 'x' now pollutes the query namespace
3133 # So the following works as expected
3134 my $ok_rs = $rs->search({'x.other' => 1});
3136 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
3137 # def) we look for one row with contradictory terms and join in another table
3138 # (aliased 'x_2') which we never use
3139 my $broken_rs = $rs->search({'x.name' => 'def'});
3141 my $rs2 = $rs->as_subselect_rs;
3143 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
3144 my $not_joined_rs = $rs2->search({'x.other' => 1});
3146 # works as expected: finds a 'table' row related to two x rows (abc and def)
3147 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
3149 Another example of when one might use this would be to select a subset of
3150 columns in a group by clause:
3152 my $rs = $schema->resultset('Bar')->search(undef, {
3153 group_by => [qw{ id foo_id baz_id }],
3154 })->as_subselect_rs->search(undef, {
3155 columns => [qw{ id foo_id }]
3158 In the above example normally columns would have to be equal to the group by,
3159 but because we isolated the group by into a subselect the above works.
3163 sub as_subselect_rs {
3166 my $attrs = $self->_resolved_attrs;
3168 my $fresh_rs = (ref $self)->new (
3169 $self->result_source
3172 # these pieces will be locked in the subquery
3173 delete $fresh_rs->{cond};
3174 delete @{$fresh_rs->{attrs}}{qw/where bind/};
3176 return $fresh_rs->search( {}, {
3178 $attrs->{alias} => $self->as_query,
3179 -alias => $attrs->{alias},
3180 -rsrc => $self->result_source,
3182 alias => $attrs->{alias},
3186 # This code is called by search_related, and makes sure there
3187 # is clear separation between the joins before, during, and
3188 # after the relationship. This information is needed later
3189 # in order to properly resolve prefetch aliases (any alias
3190 # with a relation_chain_depth less than the depth of the
3191 # current prefetch is not considered)
3193 # The increments happen twice per join. An even number means a
3194 # relationship specified via a search_related, whereas an odd
3195 # number indicates a join/prefetch added via attributes
3197 # Also this code will wrap the current resultset (the one we
3198 # chain to) in a subselect IFF it contains limiting attributes
3199 sub _chain_relationship {
3200 my ($self, $rel) = @_;
3201 my $source = $self->result_source;
3202 my $attrs = { %{$self->{attrs}||{}} };
3204 # we need to take the prefetch the attrs into account before we
3205 # ->_resolve_join as otherwise they get lost - captainL
3206 my $join = $self->_merge_joinpref_attr( $attrs->{join}, $attrs->{prefetch} );
3208 delete @{$attrs}{qw/join prefetch collapse group_by distinct select as columns +select +as +columns/};
3210 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
3213 my @force_subq_attrs = qw/offset rows group_by having/;
3216 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
3218 $self->_has_resolved_attr (@force_subq_attrs)
3220 # Nuke the prefetch (if any) before the new $rs attrs
3221 # are resolved (prefetch is useless - we are wrapping
3222 # a subquery anyway).
3223 my $rs_copy = $self->search;
3224 $rs_copy->{attrs}{join} = $self->_merge_joinpref_attr (
3225 $rs_copy->{attrs}{join},
3226 delete $rs_copy->{attrs}{prefetch},
3231 -alias => $attrs->{alias},
3232 $attrs->{alias} => $rs_copy->as_query,
3234 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
3235 $seen->{-relation_chain_depth} = 0;
3237 elsif ($attrs->{from}) { #shallow copy suffices
3238 $from = [ @{$attrs->{from}} ];
3243 -alias => $attrs->{alias},
3244 $attrs->{alias} => $source->from,
3248 my $jpath = ($seen->{-relation_chain_depth})
3249 ? $from->[-1][0]{-join_path}
3252 my @requested_joins = $source->_resolve_join(
3259 push @$from, @requested_joins;
3261 $seen->{-relation_chain_depth}++;
3263 # if $self already had a join/prefetch specified on it, the requested
3264 # $rel might very well be already included. What we do in this case
3265 # is effectively a no-op (except that we bump up the chain_depth on
3266 # the join in question so we could tell it *is* the search_related)
3269 # we consider the last one thus reverse
3270 for my $j (reverse @requested_joins) {
3271 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
3272 if ($rel eq $last_j) {
3273 $j->[0]{-relation_chain_depth}++;
3279 unless ($already_joined) {
3280 push @$from, $source->_resolve_join(
3288 $seen->{-relation_chain_depth}++;
3290 return {%$attrs, from => $from, seen_join => $seen};
3293 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
3294 sub _resolved_attrs_copy {
3296 return { %{$self->_resolved_attrs (@_)} };
3299 sub _resolved_attrs {
3301 return $self->{_attrs} if $self->{_attrs};
3303 my $attrs = { %{ $self->{attrs} || {} } };
3304 my $source = $self->result_source;
3305 my $alias = $attrs->{alias};
3307 # default selection list
3308 $attrs->{columns} = [ $source->columns ]
3309 unless List::Util::first { exists $attrs->{$_} } qw/columns cols select as/;
3311 # merge selectors together
3312 for (qw/columns select as/) {
3313 $attrs->{$_} = $self->_merge_attr($attrs->{$_}, delete $attrs->{"+$_"})
3314 if $attrs->{$_} or $attrs->{"+$_"};
3317 # disassemble columns
3319 if (my $cols = delete $attrs->{columns}) {
3320 for my $c (ref $cols eq 'ARRAY' ? @$cols : $cols) {
3321 if (ref $c eq 'HASH') {
3322 for my $as (keys %$c) {
3323 push @sel, $c->{$as};
3334 # when trying to weed off duplicates later do not go past this point -
3335 # everything added from here on is unbalanced "anyone's guess" stuff
3336 my $dedup_stop_idx = $#as;
3338 push @as, @{ ref $attrs->{as} eq 'ARRAY' ? $attrs->{as} : [ $attrs->{as} ] }
3340 push @sel, @{ ref $attrs->{select} eq 'ARRAY' ? $attrs->{select} : [ $attrs->{select} ] }
3341 if $attrs->{select};
3343 # assume all unqualified selectors to apply to the current alias (legacy stuff)
3345 $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_";
3348 # disqualify all $alias.col as-bits (collapser mandated)
3350 $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_;
3353 # de-duplicate the result (remove *identical* select/as pairs)
3354 # and also die on duplicate {as} pointing to different {select}s
3355 # not using a c-style for as the condition is prone to shrinkage
3358 while ($i <= $dedup_stop_idx) {
3359 if ($seen->{"$sel[$i] \x00\x00 $as[$i]"}++) {
3364 elsif ($seen->{$as[$i]}++) {
3365 $self->throw_exception(
3366 "inflate_result() alias '$as[$i]' specified twice with different SQL-side {select}-ors"
3374 $attrs->{select} = \@sel;
3375 $attrs->{as} = \@as;
3377 $attrs->{from} ||= [{
3379 -alias => $self->{attrs}{alias},
3380 $self->{attrs}{alias} => $source->from,
3383 if ( $attrs->{join} || $attrs->{prefetch} ) {
3385 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3386 if ref $attrs->{from} ne 'ARRAY';
3388 my $join = (delete $attrs->{join}) || {};
3390 if ( defined $attrs->{prefetch} ) {
3391 $join = $self->_merge_joinpref_attr( $join, $attrs->{prefetch} );
3394 $attrs->{from} = # have to copy here to avoid corrupting the original
3396 @{ $attrs->{from} },
3397 $source->_resolve_join(
3400 { %{ $attrs->{seen_join} || {} } },
3401 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3402 ? $attrs->{from}[-1][0]{-join_path}
3409 if ( defined $attrs->{order_by} ) {
3410 $attrs->{order_by} = (
3411 ref( $attrs->{order_by} ) eq 'ARRAY'
3412 ? [ @{ $attrs->{order_by} } ]
3413 : [ $attrs->{order_by} || () ]
3417 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3418 $attrs->{group_by} = [ $attrs->{group_by} ];
3421 # generate the distinct induced group_by early, as prefetch will be carried via a
3422 # subquery (since a group_by is present)
3423 if (delete $attrs->{distinct}) {
3424 if ($attrs->{group_by}) {
3425 carp_unique ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3428 # distinct affects only the main selection part, not what prefetch may
3430 $attrs->{group_by} = $source->storage->_group_over_selection (
3438 $attrs->{collapse} ||= {};
3439 if ($attrs->{prefetch}) {
3441 $self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
3442 if $attrs->{_dark_selector};
3444 my $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} );
3446 my $prefetch_ordering = [];
3448 # this is a separate structure (we don't look in {from} directly)
3449 # as the resolver needs to shift things off the lists to work
3450 # properly (identical-prefetches on different branches)
3452 if (ref $attrs->{from} eq 'ARRAY') {
3454 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3456 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3457 next unless $j->[0]{-alias};
3458 next unless $j->[0]{-join_path};
3459 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3461 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3464 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3465 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3470 $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
3472 # we need to somehow mark which columns came from prefetch
3474 my $sel_end = $#{$attrs->{select}};
3475 $attrs->{_prefetch_selector_range} = [ $sel_end + 1, $sel_end + @prefetch ];
3478 push @{ $attrs->{select} }, (map { $_->[0] } @prefetch);
3479 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
3481 push( @{$attrs->{order_by}}, @$prefetch_ordering );
3482 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
3485 # if both page and offset are specified, produce a combined offset
3486 # even though it doesn't make much sense, this is what pre 081xx has
3488 if (my $page = delete $attrs->{page}) {
3490 ($attrs->{rows} * ($page - 1))
3492 ($attrs->{offset} || 0)
3496 return $self->{_attrs} = $attrs;
3500 my ($self, $attr) = @_;
3502 if (ref $attr eq 'HASH') {
3503 return $self->_rollout_hash($attr);
3504 } elsif (ref $attr eq 'ARRAY') {
3505 return $self->_rollout_array($attr);
3511 sub _rollout_array {
3512 my ($self, $attr) = @_;
3515 foreach my $element (@{$attr}) {
3516 if (ref $element eq 'HASH') {
3517 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3518 } elsif (ref $element eq 'ARRAY') {
3519 # XXX - should probably recurse here
3520 push( @rolled_array, @{$self->_rollout_array($element)} );
3522 push( @rolled_array, $element );
3525 return \@rolled_array;
3529 my ($self, $attr) = @_;
3532 foreach my $key (keys %{$attr}) {
3533 push( @rolled_array, { $key => $attr->{$key} } );
3535 return \@rolled_array;
3538 sub _calculate_score {
3539 my ($self, $a, $b) = @_;
3541 if (defined $a xor defined $b) {
3544 elsif (not defined $a) {
3548 if (ref $b eq 'HASH') {
3549 my ($b_key) = keys %{$b};
3550 if (ref $a eq 'HASH') {
3551 my ($a_key) = keys %{$a};
3552 if ($a_key eq $b_key) {
3553 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3558 return ($a eq $b_key) ? 1 : 0;
3561 if (ref $a eq 'HASH') {
3562 my ($a_key) = keys %{$a};
3563 return ($b eq $a_key) ? 1 : 0;
3565 return ($b eq $a) ? 1 : 0;
3570 sub _merge_joinpref_attr {
3571 my ($self, $orig, $import) = @_;
3573 return $import unless defined($orig);
3574 return $orig unless defined($import);
3576 $orig = $self->_rollout_attr($orig);
3577 $import = $self->_rollout_attr($import);
3580 foreach my $import_element ( @{$import} ) {
3581 # find best candidate from $orig to merge $b_element into
3582 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3583 foreach my $orig_element ( @{$orig} ) {
3584 my $score = $self->_calculate_score( $orig_element, $import_element );
3585 if ($score > $best_candidate->{score}) {
3586 $best_candidate->{position} = $position;
3587 $best_candidate->{score} = $score;
3591 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3592 $import_key = '' if not defined $import_key;
3594 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3595 push( @{$orig}, $import_element );
3597 my $orig_best = $orig->[$best_candidate->{position}];
3598 # merge orig_best and b_element together and replace original with merged
3599 if (ref $orig_best ne 'HASH') {
3600 $orig->[$best_candidate->{position}] = $import_element;
3601 } elsif (ref $import_element eq 'HASH') {
3602 my ($key) = keys %{$orig_best};
3603 $orig->[$best_candidate->{position}] = { $key => $self->_merge_joinpref_attr($orig_best->{$key}, $import_element->{$key}) };
3606 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3617 require Hash::Merge;
3618 my $hm = Hash::Merge->new;
3620 $hm->specify_behavior({
3623 my ($defl, $defr) = map { defined $_ } (@_[0,1]);
3625 if ($defl xor $defr) {
3626 return [ $defl ? $_[0] : $_[1] ];
3631 elsif (__HM_DEDUP and $_[0] eq $_[1]) {
3635 return [$_[0], $_[1]];
3639 return $_[1] if !defined $_[0];
3640 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3641 return [$_[0], @{$_[1]}]
3644 return [] if !defined $_[0] and !keys %{$_[1]};
3645 return [ $_[1] ] if !defined $_[0];
3646 return [ $_[0] ] if !keys %{$_[1]};
3647 return [$_[0], $_[1]]
3652 return $_[0] if !defined $_[1];
3653 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3654 return [@{$_[0]}, $_[1]]
3657 my @ret = @{$_[0]} or return $_[1];
3658 return [ @ret, @{$_[1]} ] unless __HM_DEDUP;
3659 my %idx = map { $_ => 1 } @ret;
3660 push @ret, grep { ! defined $idx{$_} } (@{$_[1]});
3664 return [ $_[1] ] if ! @{$_[0]};
3665 return $_[0] if !keys %{$_[1]};
3666 return $_[0] if __HM_DEDUP and List::Util::first { $_ eq $_[1] } @{$_[0]};
3667 return [ @{$_[0]}, $_[1] ];
3672 return [] if !keys %{$_[0]} and !defined $_[1];
3673 return [ $_[0] ] if !defined $_[1];
3674 return [ $_[1] ] if !keys %{$_[0]};
3675 return [$_[0], $_[1]]
3678 return [] if !keys %{$_[0]} and !@{$_[1]};
3679 return [ $_[0] ] if !@{$_[1]};
3680 return $_[1] if !keys %{$_[0]};
3681 return $_[1] if __HM_DEDUP and List::Util::first { $_ eq $_[0] } @{$_[1]};
3682 return [ $_[0], @{$_[1]} ];
3685 return [] if !keys %{$_[0]} and !keys %{$_[1]};
3686 return [ $_[0] ] if !keys %{$_[1]};
3687 return [ $_[1] ] if !keys %{$_[0]};
3688 return [ $_[0] ] if $_[0] eq $_[1];
3689 return [ $_[0], $_[1] ];
3692 } => 'DBIC_RS_ATTR_MERGER');
3696 return $hm->merge ($_[1], $_[2]);
3700 sub STORABLE_freeze {
3701 my ($self, $cloning) = @_;
3702 my $to_serialize = { %$self };
3704 # A cursor in progress can't be serialized (and would make little sense anyway)
3705 delete $to_serialize->{cursor};
3707 # nor is it sensical to store a not-yet-fired-count pager
3708 if ($to_serialize->{pager} and ref $to_serialize->{pager}{total_entries} eq 'CODE') {
3709 delete $to_serialize->{pager};
3712 Storable::nfreeze($to_serialize);
3715 # need this hook for symmetry
3717 my ($self, $cloning, $serialized) = @_;
3719 %$self = %{ Storable::thaw($serialized) };
3725 =head2 throw_exception
3727 See L<DBIx::Class::Schema/throw_exception> for details.
3731 sub throw_exception {
3734 if (ref $self and my $rsrc = $self->result_source) {
3735 $rsrc->throw_exception(@_)
3738 DBIx::Class::Exception->throw(@_);
3742 # XXX: FIXME: Attributes docs need clearing up
3746 Attributes are used to refine a ResultSet in various ways when
3747 searching for data. They can be passed to any method which takes an
3748 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3751 These are in no particular order:
3757 =item Value: ( $order_by | \@order_by | \%order_by )
3761 Which column(s) to order the results by.
3763 [The full list of suitable values is documented in
3764 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3767 If a single column name, or an arrayref of names is supplied, the
3768 argument is passed through directly to SQL. The hashref syntax allows
3769 for connection-agnostic specification of ordering direction:
3771 For descending order:
3773 order_by => { -desc => [qw/col1 col2 col3/] }
3775 For explicit ascending order:
3777 order_by => { -asc => 'col' }
3779 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3780 supported, although you are strongly encouraged to use the hashref
3781 syntax as outlined above.
3787 =item Value: \@columns
3791 Shortcut to request a particular set of columns to be retrieved. Each
3792 column spec may be a string (a table column name), or a hash (in which
3793 case the key is the C<as> value, and the value is used as the C<select>
3794 expression). Adds C<me.> onto the start of any column without a C<.> in
3795 it and sets C<select> from that, then auto-populates C<as> from
3796 C<select> as normal. (You may also use the C<cols> attribute, as in
3797 earlier versions of DBIC.)
3799 Essentially C<columns> does the same as L</select> and L</as>.
3801 columns => [ 'foo', { bar => 'baz' } ]
3805 select => [qw/foo baz/],
3812 =item Value: \@columns
3816 Indicates additional columns to be selected from storage. Works the same
3817 as L</columns> but adds columns to the selection. (You may also use the
3818 C<include_columns> attribute, as in earlier versions of DBIC). For
3821 $schema->resultset('CD')->search(undef, {
3822 '+columns' => ['artist.name'],
3826 would return all CDs and include a 'name' column to the information
3827 passed to object inflation. Note that the 'artist' is the name of the
3828 column (or relationship) accessor, and 'name' is the name of the column
3829 accessor in the related table.
3831 B<NOTE:> You need to explicitly quote '+columns' when defining the attribute.
3832 Not doing so causes Perl to incorrectly interpret +columns as a bareword with a
3833 unary plus operator before it.
3835 =head2 include_columns
3839 =item Value: \@columns
3843 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3849 =item Value: \@select_columns
3853 Indicates which columns should be selected from the storage. You can use
3854 column names, or in the case of RDBMS back ends, function or stored procedure
3857 $rs = $schema->resultset('Employee')->search(undef, {
3860 { count => 'employeeid' },
3861 { max => { length => 'name' }, -as => 'longest_name' }
3866 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
3868 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
3869 use L</select>, to instruct DBIx::Class how to store the result of the column.
3870 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
3871 identifier aliasing. You can however alias a function, so you can use it in
3872 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
3873 attribute> supplied as shown in the example above.
3875 B<NOTE:> You need to explicitly quote '+select'/'+as' when defining the attributes.
3876 Not doing so causes Perl to incorrectly interpret them as a bareword with a
3877 unary plus operator before it.
3883 Indicates additional columns to be selected from storage. Works the same as
3884 L</select> but adds columns to the default selection, instead of specifying
3893 Indicates additional column names for those added via L</+select>. See L</as>.
3901 =item Value: \@inflation_names
3905 Indicates column names for object inflation. That is L</as> indicates the
3906 slot name in which the column value will be stored within the
3907 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
3908 identifier by the C<get_column> method (or via the object accessor B<if one
3909 with the same name already exists>) as shown below. The L</as> attribute has
3910 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
3912 $rs = $schema->resultset('Employee')->search(undef, {
3915 { count => 'employeeid' },
3916 { max => { length => 'name' }, -as => 'longest_name' }
3925 If the object against which the search is performed already has an accessor
3926 matching a column name specified in C<as>, the value can be retrieved using
3927 the accessor as normal:
3929 my $name = $employee->name();
3931 If on the other hand an accessor does not exist in the object, you need to
3932 use C<get_column> instead:
3934 my $employee_count = $employee->get_column('employee_count');
3936 You can create your own accessors if required - see
3937 L<DBIx::Class::Manual::Cookbook> for details.
3943 =item Value: ($rel_name | \@rel_names | \%rel_names)
3947 Contains a list of relationships that should be joined for this query. For
3950 # Get CDs by Nine Inch Nails
3951 my $rs = $schema->resultset('CD')->search(
3952 { 'artist.name' => 'Nine Inch Nails' },
3953 { join => 'artist' }
3956 Can also contain a hash reference to refer to the other relation's relations.
3959 package MyApp::Schema::Track;
3960 use base qw/DBIx::Class/;
3961 __PACKAGE__->table('track');
3962 __PACKAGE__->add_columns(qw/trackid cd position title/);
3963 __PACKAGE__->set_primary_key('trackid');
3964 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3967 # In your application
3968 my $rs = $schema->resultset('Artist')->search(
3969 { 'track.title' => 'Teardrop' },
3971 join => { cd => 'track' },
3972 order_by => 'artist.name',
3976 You need to use the relationship (not the table) name in conditions,
3977 because they are aliased as such. The current table is aliased as "me", so
3978 you need to use me.column_name in order to avoid ambiguity. For example:
3980 # Get CDs from 1984 with a 'Foo' track
3981 my $rs = $schema->resultset('CD')->search(
3984 'tracks.name' => 'Foo'
3986 { join => 'tracks' }
3989 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3990 similarly for a third time). For e.g.
3992 my $rs = $schema->resultset('Artist')->search({
3993 'cds.title' => 'Down to Earth',
3994 'cds_2.title' => 'Popular',
3996 join => [ qw/cds cds/ ],
3999 will return a set of all artists that have both a cd with title 'Down
4000 to Earth' and a cd with title 'Popular'.
4002 If you want to fetch related objects from other tables as well, see C<prefetch>
4005 NOTE: An internal join-chain pruner will discard certain joins while
4006 constructing the actual SQL query, as long as the joins in question do not
4007 affect the retrieved result. This for example includes 1:1 left joins
4008 that are not part of the restriction specification (WHERE/HAVING) nor are
4009 a part of the query selection.
4011 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
4017 =item Value: ($rel_name | \@rel_names | \%rel_names)
4021 Contains one or more relationships that should be fetched along with
4022 the main query (when they are accessed afterwards the data will
4023 already be available, without extra queries to the database). This is
4024 useful for when you know you will need the related objects, because it
4025 saves at least one query:
4027 my $rs = $schema->resultset('Tag')->search(
4036 The initial search results in SQL like the following:
4038 SELECT tag.*, cd.*, artist.* FROM tag
4039 JOIN cd ON tag.cd = cd.cdid
4040 JOIN artist ON cd.artist = artist.artistid
4042 L<DBIx::Class> has no need to go back to the database when we access the
4043 C<cd> or C<artist> relationships, which saves us two SQL statements in this
4046 Simple prefetches will be joined automatically, so there is no need
4047 for a C<join> attribute in the above search.
4049 L</prefetch> can be used with the any of the relationship types and
4050 multiple prefetches can be specified together. Below is a more complex
4051 example that prefetches a CD's artist, its liner notes (if present),
4052 the cover image, the tracks on that cd, and the guests on those
4056 My::Schema::CD->belongs_to( artist => 'My::Schema::Artist' );
4057 My::Schema::CD->might_have( liner_note => 'My::Schema::LinerNotes' );
4058 My::Schema::CD->has_one( cover_image => 'My::Schema::Artwork' );
4059 My::Schema::CD->has_many( tracks => 'My::Schema::Track' );
4061 My::Schema::Artist->belongs_to( record_label => 'My::Schema::RecordLabel' );
4063 My::Schema::Track->has_many( guests => 'My::Schema::Guest' );
4066 my $rs = $schema->resultset('CD')->search(
4070 { artist => 'record_label'}, # belongs_to => belongs_to
4071 'liner_note', # might_have
4072 'cover_image', # has_one
4073 { tracks => 'guests' }, # has_many => has_many
4078 This will produce SQL like the following:
4080 SELECT cd.*, artist.*, record_label.*, liner_note.*, cover_image.*,
4084 ON artist.artistid = me.artistid
4085 JOIN record_label record_label
4086 ON record_label.labelid = artist.labelid
4087 LEFT JOIN track tracks
4088 ON tracks.cdid = me.cdid
4089 LEFT JOIN guest guests
4090 ON guests.trackid = track.trackid
4091 LEFT JOIN liner_notes liner_note
4092 ON liner_note.cdid = me.cdid
4093 JOIN cd_artwork cover_image
4094 ON cover_image.cdid = me.cdid
4097 Now the C<artist>, C<record_label>, C<liner_note>, C<cover_image>,
4098 C<tracks>, and C<guests> of the CD will all be available through the
4099 relationship accessors without the need for additional queries to the
4102 However, there is one caveat to be observed: it can be dangerous to
4103 prefetch more than one L<has_many|DBIx::Class::Relationship/has_many>
4104 relationship on a given level. e.g.:
4106 my $rs = $schema->resultset('CD')->search(
4110 'tracks', # has_many
4111 { cd_to_producer => 'producer' }, # has_many => belongs_to (i.e. m2m)
4116 In fact, C<DBIx::Class> will emit the following warning:
4118 Prefetching multiple has_many rels tracks and cd_to_producer at top
4119 level will explode the number of row objects retrievable via ->next
4120 or ->all. Use at your own risk.
4122 The collapser currently can't identify duplicate tuples for multiple
4123 L<has_many|DBIx::Class::Relationship/has_many> relationships and as a
4124 result the second L<has_many|DBIx::Class::Relationship/has_many>
4125 relation could contain redundant objects.
4127 =head3 Using L</prefetch> with L</join>
4129 L</prefetch> implies a L</join> with the equivalent argument, and is
4130 properly merged with any existing L</join> specification. So the
4133 my $rs = $schema->resultset('CD')->search(
4134 {'record_label.name' => 'Music Product Ltd.'},
4136 join => {artist => 'record_label'},
4137 prefetch => 'artist',
4141 ... will work, searching on the record label's name, but only
4142 prefetching the C<artist>.
4144 =head3 Using L</prefetch> with L</select> / L</+select> / L</as> / L</+as>
4146 L</prefetch> implies a L</+select>/L</+as> with the fields of the
4147 prefetched relations. So given:
4149 my $rs = $schema->resultset('CD')->search(
4152 select => ['cd.title'],
4154 prefetch => 'artist',
4158 The L</select> becomes: C<'cd.title', 'artist.*'> and the L</as>
4159 becomes: C<'cd_title', 'artist.*'>.
4163 Prefetch does a lot of deep magic. As such, it may not behave exactly
4164 as you might expect.
4170 Prefetch uses the L</cache> to populate the prefetched relationships. This
4171 may or may not be what you want.
4175 If you specify a condition on a prefetched relationship, ONLY those
4176 rows that match the prefetched condition will be fetched into that relationship.
4177 This means that adding prefetch to a search() B<may alter> what is returned by
4178 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
4180 my $artist_rs = $schema->resultset('Artist')->search({
4186 my $count = $artist_rs->first->cds->count;
4188 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
4190 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
4192 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
4194 that cmp_ok() may or may not pass depending on the datasets involved. This
4195 behavior may or may not survive the 0.09 transition.
4207 Makes the resultset paged and specifies the page to retrieve. Effectively
4208 identical to creating a non-pages resultset and then calling ->page($page)
4211 If L</rows> attribute is not specified it defaults to 10 rows per page.
4213 When you have a paged resultset, L</count> will only return the number
4214 of rows in the page. To get the total, use the L</pager> and call
4215 C<total_entries> on it.
4225 Specifies the maximum number of rows for direct retrieval or the number of
4226 rows per page if the page attribute or method is used.
4232 =item Value: $offset
4236 Specifies the (zero-based) row number for the first row to be returned, or the
4237 of the first row of the first page if paging is used.
4239 =head2 software_limit
4243 =item Value: (0 | 1)
4247 When combined with L</rows> and/or L</offset> the generated SQL will not
4248 include any limit dialect stanzas. Instead the entire result will be selected
4249 as if no limits were specified, and DBIC will perform the limit locally, by
4250 artificially advancing and finishing the resulting L</cursor>.
4252 This is the recommended way of performing resultset limiting when no sane RDBMS
4253 implementation is available (e.g.
4254 L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
4255 L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
4261 =item Value: \@columns
4265 A arrayref of columns to group by. Can include columns of joined tables.
4267 group_by => [qw/ column1 column2 ... /]
4273 =item Value: $condition
4277 HAVING is a select statement attribute that is applied between GROUP BY and
4278 ORDER BY. It is applied to the after the grouping calculations have been
4281 having => { 'count_employee' => { '>=', 100 } }
4283 or with an in-place function in which case literal SQL is required:
4285 having => \[ 'count(employee) >= ?', [ count => 100 ] ]
4291 =item Value: (0 | 1)
4295 Set to 1 to group by all columns. If the resultset already has a group_by
4296 attribute, this setting is ignored and an appropriate warning is issued.
4302 Adds to the WHERE clause.
4304 # only return rows WHERE deleted IS NULL for all searches
4305 __PACKAGE__->resultset_attributes({ where => { deleted => undef } });
4307 Can be overridden by passing C<< { where => undef } >> as an attribute
4310 For more complicated where clauses see L<SQL::Abstract/WHERE CLAUSES>.
4316 Set to 1 to cache search results. This prevents extra SQL queries if you
4317 revisit rows in your ResultSet:
4319 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
4321 while( my $artist = $resultset->next ) {
4325 $rs->first; # without cache, this would issue a query
4327 By default, searches are not cached.
4329 For more examples of using these attributes, see
4330 L<DBIx::Class::Manual::Cookbook>.
4336 =item Value: ( 'update' | 'shared' | \$scalar )
4340 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT
4341 ... FOR SHARED. If \$scalar is passed, this is taken directly and embedded in the
4344 =head1 AUTHOR AND CONTRIBUTORS
4346 See L<AUTHOR|DBIx::Class/AUTHOR> and L<CONTRIBUTORS|DBIx::Class/CONTRIBUTORS> in DBIx::Class
4350 You may distribute this code under the same terms as Perl itself.