1 package DBIx::Class::ResultSet;
9 use Carp::Clan qw/^DBIx::Class/;
10 use DBIx::Class::Exception;
13 use DBIx::Class::ResultSetColumn;
14 use DBIx::Class::ResultSourceHandle;
17 use base qw/DBIx::Class/;
19 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class _source_handle/);
23 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
27 my $users_rs = $schema->resultset('User');
28 while( $user = $users_rs->next) {
29 print $user->username;
32 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
33 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
37 A ResultSet is an object which stores a set of conditions representing
38 a query. It is the backbone of DBIx::Class (i.e. the really
39 important/useful bit).
41 No SQL is executed on the database when a ResultSet is created, it
42 just stores all the conditions needed to create the query.
44 A basic ResultSet representing the data of an entire table is returned
45 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
46 L<Source|DBIx::Class::Manual::Glossary/Source> name.
48 my $users_rs = $schema->resultset('User');
50 A new ResultSet is returned from calling L</search> on an existing
51 ResultSet. The new one will contain all the conditions of the
52 original, plus any new conditions added in the C<search> call.
54 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
55 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
58 The query that the ResultSet represents is B<only> executed against
59 the database when these methods are called:
60 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
62 If a resultset is used in a numeric context it returns the L</count>.
63 However, if it is used in a boolean context it is B<always> true. So if
64 you want to check if a resultset has any results, you must use C<if $rs
69 =head2 Chaining resultsets
71 Let's say you've got a query that needs to be run to return some data
72 to the user. But, you have an authorization system in place that
73 prevents certain users from seeing certain information. So, you want
74 to construct the basic query in one method, but add constraints to it in
79 my $request = $self->get_request; # Get a request object somehow.
80 my $schema = $self->get_schema; # Get the DBIC schema object somehow.
82 my $cd_rs = $schema->resultset('CD')->search({
83 title => $request->param('title'),
84 year => $request->param('year'),
87 $self->apply_security_policy( $cd_rs );
92 sub apply_security_policy {
101 =head3 Resolving conditions and attributes
103 When a resultset is chained from another resultset, conditions and
104 attributes with the same keys need resolving.
106 L</join>, L</prefetch>, L</+select>, L</+as> attributes are merged
107 into the existing ones from the original resultset.
109 The L</where> and L</having> attributes, and any search conditions, are
110 merged with an SQL C<AND> to the existing condition from the original
113 All other attributes are overridden by any new ones supplied in the
116 =head2 Multiple queries
118 Since a resultset just defines a query, you can do all sorts of
119 things with it with the same object.
121 # Don't hit the DB yet.
122 my $cd_rs = $schema->resultset('CD')->search({
123 title => 'something',
127 # Each of these hits the DB individually.
128 my $count = $cd_rs->count;
129 my $most_recent = $cd_rs->get_column('date_released')->max();
130 my @records = $cd_rs->all;
132 And it's not just limited to SELECT statements.
138 $cd_rs->create({ artist => 'Fred' });
140 Which is the same as:
142 $schema->resultset('CD')->create({
143 title => 'something',
148 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
156 =item Arguments: $source, \%$attrs
158 =item Return Value: $rs
162 The resultset constructor. Takes a source object (usually a
163 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
164 L</ATTRIBUTES> below). Does not perform any queries -- these are
165 executed as needed by the other methods.
167 Generally you won't need to construct a resultset manually. You'll
168 automatically get one from e.g. a L</search> called in scalar context:
170 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
172 IMPORTANT: If called on an object, proxies to new_result instead so
174 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
176 will return a CD object, not a ResultSet.
182 return $class->new_result(@_) if ref $class;
184 my ($source, $attrs) = @_;
185 $source = $source->handle
186 unless $source->isa('DBIx::Class::ResultSourceHandle');
187 $attrs = { %{$attrs||{}} };
189 if ($attrs->{page}) {
190 $attrs->{rows} ||= 10;
193 $attrs->{alias} ||= 'me';
195 # Creation of {} and bless separated to mitigate RH perl bug
196 # see https://bugzilla.redhat.com/show_bug.cgi?id=196836
198 _source_handle => $source,
199 cond => $attrs->{where},
207 $attrs->{result_class} || $source->resolve->result_class
217 =item Arguments: $cond, \%attrs?
219 =item Return Value: $resultset (scalar context), @row_objs (list context)
223 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
224 my $new_rs = $cd_rs->search({ year => 2005 });
226 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
227 # year = 2005 OR year = 2004
229 If you need to pass in additional attributes but no additional condition,
230 call it as C<search(undef, \%attrs)>.
232 # "SELECT name, artistid FROM $artist_table"
233 my @all_artists = $schema->resultset('Artist')->search(undef, {
234 columns => [qw/name artistid/],
237 For a list of attributes that can be passed to C<search>, see
238 L</ATTRIBUTES>. For more examples of using this function, see
239 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
240 documentation for the first argument, see L<SQL::Abstract>.
242 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
248 my $rs = $self->search_rs( @_ );
249 return (wantarray ? $rs->all : $rs);
256 =item Arguments: $cond, \%attrs?
258 =item Return Value: $resultset
262 This method does the same exact thing as search() except it will
263 always return a resultset, even in list context.
270 # Special-case handling for (undef, undef).
271 if ( @_ == 2 && !defined $_[1] && !defined $_[0] ) {
276 $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
277 my $our_attrs = { %{$self->{attrs}} };
278 my $having = delete $our_attrs->{having};
279 my $where = delete $our_attrs->{where};
283 my %safe = (alias => 1, cache => 1);
286 (@_ && defined($_[0])) # @_ == () or (undef)
288 (keys %$attrs # empty attrs or only 'safe' attrs
289 && List::Util::first { !$safe{$_} } keys %$attrs)
291 # no search, effectively just a clone
292 $rows = $self->get_cache;
295 # reset the selector list
296 if (List::Util::first { exists $attrs->{$_} } qw{columns select as}) {
297 delete @{$our_attrs}{qw{select as columns +select +as +columns include_columns}};
300 my $new_attrs = { %{$our_attrs}, %{$attrs} };
302 # merge new attrs into inherited
303 foreach my $key (qw/join prefetch +select +as +columns include_columns bind/) {
304 next unless exists $attrs->{$key};
305 $new_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key});
310 (@_ == 1 || ref $_[0] eq "HASH")
312 (ref $_[0] eq 'HASH')
314 (keys %{ $_[0] } > 0)
322 ? $self->throw_exception("Odd number of arguments to search")
329 if (defined $where) {
330 $new_attrs->{where} = (
331 defined $new_attrs->{where}
334 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
335 } $where, $new_attrs->{where}
342 $new_attrs->{where} = (
343 defined $new_attrs->{where}
346 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
347 } $cond, $new_attrs->{where}
353 if (defined $having) {
354 $new_attrs->{having} = (
355 defined $new_attrs->{having}
358 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
359 } $having, $new_attrs->{having}
365 my $rs = (ref $self)->new($self->result_source, $new_attrs);
367 $rs->set_cache($rows) if ($rows);
372 =head2 search_literal
376 =item Arguments: $sql_fragment, @bind_values
378 =item Return Value: $resultset (scalar context), @row_objs (list context)
382 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
383 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
385 Pass a literal chunk of SQL to be added to the conditional part of the
388 CAVEAT: C<search_literal> is provided for Class::DBI compatibility and should
389 only be used in that context. C<search_literal> is a convenience method.
390 It is equivalent to calling $schema->search(\[]), but if you want to ensure
391 columns are bound correctly, use C<search>.
393 Example of how to use C<search> instead of C<search_literal>
395 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
396 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
399 See L<DBIx::Class::Manual::Cookbook/Searching> and
400 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
401 require C<search_literal>.
406 my ($self, $sql, @bind) = @_;
408 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
411 return $self->search(\[ $sql, map [ __DUMMY__ => $_ ], @bind ], ($attr || () ));
418 =item Arguments: @values | \%cols, \%attrs?
420 =item Return Value: $row_object | undef
424 Finds a row based on its primary key or unique constraint. For example, to find
425 a row by its primary key:
427 my $cd = $schema->resultset('CD')->find(5);
429 You can also find a row by a specific unique constraint using the C<key>
430 attribute. For example:
432 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
433 key => 'cd_artist_title'
436 Additionally, you can specify the columns explicitly by name:
438 my $cd = $schema->resultset('CD')->find(
440 artist => 'Massive Attack',
441 title => 'Mezzanine',
443 { key => 'cd_artist_title' }
446 If the C<key> is specified as C<primary>, it searches only on the primary key.
448 If no C<key> is specified, it searches on all unique constraints defined on the
449 source for which column data is provided, including the primary key.
451 If your table does not have a primary key, you B<must> provide a value for the
452 C<key> attribute matching one of the unique constraints on the source.
454 In addition to C<key>, L</find> recognizes and applies standard
455 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
457 Note: If your query does not return only one row, a warning is generated:
459 Query returned more than one row
461 See also L</find_or_create> and L</update_or_create>. For information on how to
462 declare unique constraints, see
463 L<DBIx::Class::ResultSource/add_unique_constraint>.
469 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
471 # Default to the primary key, but allow a specific key
472 my @cols = exists $attrs->{key}
473 ? $self->result_source->unique_constraint_columns($attrs->{key})
474 : $self->result_source->primary_columns;
475 $self->throw_exception(
476 "Can't find unless a primary key is defined or unique constraint is specified"
479 # Parse out a hashref from input
481 if (ref $_[0] eq 'HASH') {
482 $input_query = { %{$_[0]} };
484 elsif (@_ == @cols) {
486 @{$input_query}{@cols} = @_;
489 # Compatibility: Allow e.g. find(id => $value)
490 carp "Find by key => value deprecated; please use a hashref instead";
494 my (%related, $info);
496 KEY: foreach my $key (keys %$input_query) {
497 if (ref($input_query->{$key})
498 && ($info = $self->result_source->relationship_info($key))) {
499 my $val = delete $input_query->{$key};
500 next KEY if (ref($val) eq 'ARRAY'); # has_many for multi_create
501 my $rel_q = $self->result_source->_resolve_condition(
502 $info->{cond}, $val, $key
504 die "Can't handle OR join condition in find" if ref($rel_q) eq 'ARRAY';
505 @related{keys %$rel_q} = values %$rel_q;
508 if (my @keys = keys %related) {
509 @{$input_query}{@keys} = values %related;
513 # Build the final query: Default to the disjunction of the unique queries,
514 # but allow the input query in case the ResultSet defines the query or the
515 # user is abusing find
516 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
518 if (exists $attrs->{key}) {
519 my @unique_cols = $self->result_source->unique_constraint_columns($attrs->{key});
520 my $unique_query = $self->_build_unique_query($input_query, \@unique_cols);
521 $query = $self->_add_alias($unique_query, $alias);
523 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
524 # This means that we got here after a merger of relationship conditions
525 # in ::Relationship::Base::search_related (the row method), and furthermore
526 # the relationship is of the 'single' type. This means that the condition
527 # provided by the relationship (already attached to $self) is sufficient,
528 # as there can be only one row in the database that would satisfy the
532 my @unique_queries = $self->_unique_queries($input_query, $attrs);
533 $query = @unique_queries
534 ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
535 : $self->_add_alias($input_query, $alias);
538 # Run the query, passing the result_class since it should propagate for find
539 my $rs = $self->search ($query, {result_class => $self->result_class, %$attrs});
540 if (keys %{$rs->_resolved_attrs->{collapse}}) {
542 carp "Query returned more than one row" if $rs->next;
552 # Add the specified alias to the specified query hash. A copy is made so the
553 # original query is not modified.
556 my ($self, $query, $alias) = @_;
558 my %aliased = %$query;
559 foreach my $col (grep { ! m/\./ } keys %aliased) {
560 $aliased{"$alias.$col"} = delete $aliased{$col};
568 # Build a list of queries which satisfy unique constraints.
570 sub _unique_queries {
571 my ($self, $query, $attrs) = @_;
573 my @constraint_names = exists $attrs->{key}
575 : $self->result_source->unique_constraint_names;
577 my $where = $self->_collapse_cond($self->{attrs}{where} || {});
578 my $num_where = scalar keys %$where;
580 my (@unique_queries, %seen_column_combinations);
581 foreach my $name (@constraint_names) {
582 my @constraint_cols = $self->result_source->unique_constraint_columns($name);
584 my $constraint_sig = join "\x00", sort @constraint_cols;
585 next if $seen_column_combinations{$constraint_sig}++;
587 my $unique_query = $self->_build_unique_query($query, \@constraint_cols);
589 my $num_cols = scalar @constraint_cols;
590 my $num_query = scalar keys %$unique_query;
592 my $total = $num_query + $num_where;
593 if ($num_query && ($num_query == $num_cols || $total == $num_cols)) {
594 # The query is either unique on its own or is unique in combination with
595 # the existing where clause
596 push @unique_queries, $unique_query;
600 return @unique_queries;
603 # _build_unique_query
605 # Constrain the specified query hash based on the specified column names.
607 sub _build_unique_query {
608 my ($self, $query, $unique_cols) = @_;
611 map { $_ => $query->{$_} }
612 grep { exists $query->{$_} }
617 =head2 search_related
621 =item Arguments: $rel, $cond, \%attrs?
623 =item Return Value: $new_resultset
627 $new_rs = $cd_rs->search_related('artist', {
631 Searches the specified relationship, optionally specifying a condition and
632 attributes for matching records. See L</ATTRIBUTES> for more information.
637 return shift->related_resultset(shift)->search(@_);
640 =head2 search_related_rs
642 This method works exactly the same as search_related, except that
643 it guarantees a resultset, even in list context.
647 sub search_related_rs {
648 return shift->related_resultset(shift)->search_rs(@_);
655 =item Arguments: none
657 =item Return Value: $cursor
661 Returns a storage-driven cursor to the given resultset. See
662 L<DBIx::Class::Cursor> for more information.
669 my $attrs = $self->_resolved_attrs_copy;
671 return $self->{cursor}
672 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
673 $attrs->{where},$attrs);
680 =item Arguments: $cond?
682 =item Return Value: $row_object?
686 my $cd = $schema->resultset('CD')->single({ year => 2001 });
688 Inflates the first result without creating a cursor if the resultset has
689 any records in it; if not returns nothing. Used by L</find> as a lean version of
692 While this method can take an optional search condition (just like L</search>)
693 being a fast-code-path it does not recognize search attributes. If you need to
694 add extra joins or similar, call L</search> and then chain-call L</single> on the
695 L<DBIx::Class::ResultSet> returned.
701 As of 0.08100, this method enforces the assumption that the preceding
702 query returns only one row. If more than one row is returned, you will receive
705 Query returned more than one row
707 In this case, you should be using L</next> or L</find> instead, or if you really
708 know what you are doing, use the L</rows> attribute to explicitly limit the size
711 This method will also throw an exception if it is called on a resultset prefetching
712 has_many, as such a prefetch implies fetching multiple rows from the database in
713 order to assemble the resulting object.
720 my ($self, $where) = @_;
722 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
725 my $attrs = $self->_resolved_attrs_copy;
727 if (keys %{$attrs->{collapse}}) {
728 $self->throw_exception(
729 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
734 if (defined $attrs->{where}) {
737 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
738 $where, delete $attrs->{where} ]
741 $attrs->{where} = $where;
745 # XXX: Disabled since it doesn't infer uniqueness in all cases
746 # unless ($self->_is_unique_query($attrs->{where})) {
747 # carp "Query not guaranteed to return a single row"
748 # . "; please declare your unique constraints or use search instead";
751 my @data = $self->result_source->storage->select_single(
752 $attrs->{from}, $attrs->{select},
753 $attrs->{where}, $attrs
756 return (@data ? ($self->_construct_object(@data))[0] : undef);
762 # Try to determine if the specified query is guaranteed to be unique, based on
763 # the declared unique constraints.
765 sub _is_unique_query {
766 my ($self, $query) = @_;
768 my $collapsed = $self->_collapse_query($query);
769 my $alias = $self->{attrs}{alias};
771 foreach my $name ($self->result_source->unique_constraint_names) {
772 my @unique_cols = map {
774 } $self->result_source->unique_constraint_columns($name);
776 # Count the values for each unique column
777 my %seen = map { $_ => 0 } @unique_cols;
779 foreach my $key (keys %$collapsed) {
780 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
781 next unless exists $seen{$aliased}; # Additional constraints are okay
782 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
785 # If we get 0 or more than 1 value for a column, it's not necessarily unique
786 return 1 unless grep { $_ != 1 } values %seen;
794 # Recursively collapse the query, accumulating values for each column.
796 sub _collapse_query {
797 my ($self, $query, $collapsed) = @_;
801 if (ref $query eq 'ARRAY') {
802 foreach my $subquery (@$query) {
803 next unless ref $subquery; # -or
804 $collapsed = $self->_collapse_query($subquery, $collapsed);
807 elsif (ref $query eq 'HASH') {
808 if (keys %$query and (keys %$query)[0] eq '-and') {
809 foreach my $subquery (@{$query->{-and}}) {
810 $collapsed = $self->_collapse_query($subquery, $collapsed);
814 foreach my $col (keys %$query) {
815 my $value = $query->{$col};
816 $collapsed->{$col}{$value}++;
828 =item Arguments: $cond?
830 =item Return Value: $resultsetcolumn
834 my $max_length = $rs->get_column('length')->max;
836 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
841 my ($self, $column) = @_;
842 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
850 =item Arguments: $cond, \%attrs?
852 =item Return Value: $resultset (scalar context), @row_objs (list context)
856 # WHERE title LIKE '%blue%'
857 $cd_rs = $rs->search_like({ title => '%blue%'});
859 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
860 that this is simply a convenience method retained for ex Class::DBI users.
861 You most likely want to use L</search> with specific operators.
863 For more information, see L<DBIx::Class::Manual::Cookbook>.
865 This method is deprecated and will be removed in 0.09. Use L</search()>
866 instead. An example conversion is:
868 ->search_like({ foo => 'bar' });
872 ->search({ foo => { like => 'bar' } });
879 'search_like() is deprecated and will be removed in DBIC version 0.09.'
880 .' Instead use ->search({ x => { -like => "y%" } })'
881 .' (note the outer pair of {}s - they are important!)'
883 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
884 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
885 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
886 return $class->search($query, { %$attrs });
893 =item Arguments: $first, $last
895 =item Return Value: $resultset (scalar context), @row_objs (list context)
899 Returns a resultset or object list representing a subset of elements from the
900 resultset slice is called on. Indexes are from 0, i.e., to get the first
903 my ($one, $two, $three) = $rs->slice(0, 2);
908 my ($self, $min, $max) = @_;
909 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
910 $attrs->{offset} = $self->{attrs}{offset} || 0;
911 $attrs->{offset} += $min;
912 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
913 return $self->search(undef(), $attrs);
914 #my $slice = (ref $self)->new($self->result_source, $attrs);
915 #return (wantarray ? $slice->all : $slice);
922 =item Arguments: none
924 =item Return Value: $result?
928 Returns the next element in the resultset (C<undef> is there is none).
930 Can be used to efficiently iterate over records in the resultset:
932 my $rs = $schema->resultset('CD')->search;
933 while (my $cd = $rs->next) {
937 Note that you need to store the resultset object, and call C<next> on it.
938 Calling C<< resultset('Table')->next >> repeatedly will always return the
939 first record from the resultset.
945 if (my $cache = $self->get_cache) {
946 $self->{all_cache_position} ||= 0;
947 return $cache->[$self->{all_cache_position}++];
949 if ($self->{attrs}{cache}) {
950 $self->{all_cache_position} = 1;
951 return ($self->all)[0];
953 if ($self->{stashed_objects}) {
954 my $obj = shift(@{$self->{stashed_objects}});
955 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
959 exists $self->{stashed_row}
960 ? @{delete $self->{stashed_row}}
961 : $self->cursor->next
963 return undef unless (@row);
964 my ($row, @more) = $self->_construct_object(@row);
965 $self->{stashed_objects} = \@more if @more;
969 sub _construct_object {
970 my ($self, @row) = @_;
972 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row)
974 my @new = $self->result_class->inflate_result($self->result_source, @$info);
975 @new = $self->{_attrs}{record_filter}->(@new)
976 if exists $self->{_attrs}{record_filter};
980 sub _collapse_result {
981 my ($self, $as_proto, $row) = @_;
985 # 'foo' => [ undef, 'foo' ]
986 # 'foo.bar' => [ 'foo', 'bar' ]
987 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
989 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
991 my %collapse = %{$self->{_attrs}{collapse}||{}};
995 # if we're doing collapsing (has_many prefetch) we need to grab records
996 # until the PK changes, so fill @pri_index. if not, we leave it empty so
997 # we know we don't have to bother.
999 # the reason for not using the collapse stuff directly is because if you
1000 # had for e.g. two artists in a row with no cds, the collapse info for
1001 # both would be NULL (undef) so you'd lose the second artist
1003 # store just the index so we can check the array positions from the row
1004 # without having to contruct the full hash
1006 if (keys %collapse) {
1007 my %pri = map { ($_ => 1) } $self->result_source->_pri_cols;
1008 foreach my $i (0 .. $#construct_as) {
1009 next if defined($construct_as[$i][0]); # only self table
1010 if (delete $pri{$construct_as[$i][1]}) {
1011 push(@pri_index, $i);
1013 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
1017 # no need to do an if, it'll be empty if @pri_index is empty anyway
1019 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
1023 do { # no need to check anything at the front, we always want the first row
1027 foreach my $this_as (@construct_as) {
1028 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
1031 push(@const_rows, \%const);
1033 } until ( # no pri_index => no collapse => drop straight out
1036 do { # get another row, stash it, drop out if different PK
1038 @copy = $self->cursor->next;
1039 $self->{stashed_row} = \@copy;
1041 # last thing in do block, counts as true if anything doesn't match
1043 # check xor defined first for NULL vs. NOT NULL then if one is
1044 # defined the other must be so check string equality
1047 (defined $pri_vals{$_} ^ defined $copy[$_])
1048 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
1053 my $alias = $self->{attrs}{alias};
1060 foreach my $const (@const_rows) {
1061 scalar @const_keys or do {
1062 @const_keys = sort { length($a) <=> length($b) } keys %$const;
1064 foreach my $key (@const_keys) {
1067 my @parts = split(/\./, $key);
1069 my $data = $const->{$key};
1070 foreach my $p (@parts) {
1071 $target = $target->[1]->{$p} ||= [];
1073 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
1074 # collapsing at this point and on final part
1075 my $pos = $collapse_pos{$cur};
1076 CK: foreach my $ck (@ckey) {
1077 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
1078 $collapse_pos{$cur} = $data;
1079 delete @collapse_pos{ # clear all positioning for sub-entries
1080 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
1087 if (exists $collapse{$cur}) {
1088 $target = $target->[-1];
1091 $target->[0] = $data;
1093 $info->[0] = $const->{$key};
1101 =head2 result_source
1105 =item Arguments: $result_source?
1107 =item Return Value: $result_source
1111 An accessor for the primary ResultSource object from which this ResultSet
1118 =item Arguments: $result_class?
1120 =item Return Value: $result_class
1124 An accessor for the class to use when creating row objects. Defaults to
1125 C<< result_source->result_class >> - which in most cases is the name of the
1126 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1128 Note that changing the result_class will also remove any components
1129 that were originally loaded in the source class via
1130 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1131 in the original source class will not run.
1136 my ($self, $result_class) = @_;
1137 if ($result_class) {
1138 unless (ref $result_class) { # don't fire this for an object
1139 $self->ensure_class_loaded($result_class);
1141 $self->_result_class($result_class);
1142 # THIS LINE WOULD BE A BUG - this accessor specifically exists to
1143 # permit the user to set result class on one result set only; it only
1144 # chains if provided to search()
1145 #$self->{attrs}{result_class} = $result_class if ref $self;
1147 $self->_result_class;
1154 =item Arguments: $cond, \%attrs??
1156 =item Return Value: $count
1160 Performs an SQL C<COUNT> with the same query as the resultset was built
1161 with to find the number of elements. Passing arguments is equivalent to
1162 C<< $rs->search ($cond, \%attrs)->count >>
1168 return $self->search(@_)->count if @_ and defined $_[0];
1169 return scalar @{ $self->get_cache } if $self->get_cache;
1171 my $attrs = $self->_resolved_attrs_copy;
1173 # this is a little optimization - it is faster to do the limit
1174 # adjustments in software, instead of a subquery
1175 my $rows = delete $attrs->{rows};
1176 my $offset = delete $attrs->{offset};
1179 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1180 $crs = $self->_count_subq_rs ($attrs);
1183 $crs = $self->_count_rs ($attrs);
1185 my $count = $crs->next;
1187 $count -= $offset if $offset;
1188 $count = $rows if $rows and $rows < $count;
1189 $count = 0 if ($count < 0);
1198 =item Arguments: $cond, \%attrs??
1200 =item Return Value: $count_rs
1204 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1205 This can be very handy for subqueries:
1207 ->search( { amount => $some_rs->count_rs->as_query } )
1209 As with regular resultsets the SQL query will be executed only after
1210 the resultset is accessed via L</next> or L</all>. That would return
1211 the same single value obtainable via L</count>.
1217 return $self->search(@_)->count_rs if @_;
1219 # this may look like a lack of abstraction (count() does about the same)
1220 # but in fact an _rs *must* use a subquery for the limits, as the
1221 # software based limiting can not be ported if this $rs is to be used
1222 # in a subquery itself (i.e. ->as_query)
1223 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1224 return $self->_count_subq_rs;
1227 return $self->_count_rs;
1232 # returns a ResultSetColumn object tied to the count query
1235 my ($self, $attrs) = @_;
1237 my $rsrc = $self->result_source;
1238 $attrs ||= $self->_resolved_attrs;
1240 # only take pieces we need for a simple count
1241 my $tmp_attrs = { map
1242 { $_ => $attrs->{$_} }
1243 qw/ alias from where bind join /
1246 # overwrite the selector (supplied by the storage)
1247 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $tmp_attrs);
1248 $tmp_attrs->{as} = 'count';
1250 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1256 # same as above but uses a subquery
1258 sub _count_subq_rs {
1259 my ($self, $attrs) = @_;
1261 my $rsrc = $self->result_source;
1262 $attrs ||= $self->_resolved_attrs;
1264 my $sub_attrs = { map
1265 { $_ => $attrs->{$_} }
1266 qw/ alias from where bind join group_by having rows offset /
1269 # if we multi-prefetch we group_by primary keys only as this is what we would
1270 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1271 if ( keys %{$attrs->{collapse}} ) {
1272 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } ($rsrc->_pri_cols) ]
1275 # Calculate subquery selector
1276 if (my $g = $sub_attrs->{group_by}) {
1278 # necessary as the group_by may refer to aliased functions
1280 for my $sel (@{$attrs->{select}}) {
1281 $sel_index->{$sel->{-as}} = $sel
1282 if (ref $sel eq 'HASH' and $sel->{-as});
1285 for my $g_part (@$g) {
1286 push @{$sub_attrs->{select}}, $sel_index->{$g_part} || $g_part;
1290 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1291 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1294 return $rsrc->resultset_class
1295 ->new ($rsrc, $sub_attrs)
1297 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1298 -> get_column ('count');
1305 =head2 count_literal
1309 =item Arguments: $sql_fragment, @bind_values
1311 =item Return Value: $count
1315 Counts the results in a literal query. Equivalent to calling L</search_literal>
1316 with the passed arguments, then L</count>.
1320 sub count_literal { shift->search_literal(@_)->count; }
1326 =item Arguments: none
1328 =item Return Value: @objects
1332 Returns all elements in the resultset. Called implicitly if the resultset
1333 is returned in list context.
1340 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1343 return @{ $self->get_cache } if $self->get_cache;
1347 if (keys %{$self->_resolved_attrs->{collapse}}) {
1348 # Using $self->cursor->all is really just an optimisation.
1349 # If we're collapsing has_many prefetches it probably makes
1350 # very little difference, and this is cleaner than hacking
1351 # _construct_object to survive the approach
1352 $self->cursor->reset;
1353 my @row = $self->cursor->next;
1355 push(@obj, $self->_construct_object(@row));
1356 @row = (exists $self->{stashed_row}
1357 ? @{delete $self->{stashed_row}}
1358 : $self->cursor->next);
1361 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1364 $self->set_cache(\@obj) if $self->{attrs}{cache};
1373 =item Arguments: none
1375 =item Return Value: $self
1379 Resets the resultset's cursor, so you can iterate through the elements again.
1380 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1387 delete $self->{_attrs} if exists $self->{_attrs};
1388 $self->{all_cache_position} = 0;
1389 $self->cursor->reset;
1397 =item Arguments: none
1399 =item Return Value: $object?
1403 Resets the resultset and returns an object for the first result (if the
1404 resultset returns anything).
1409 return $_[0]->reset->next;
1415 # Determines whether and what type of subquery is required for the $rs operation.
1416 # If grouping is necessary either supplies its own, or verifies the current one
1417 # After all is done delegates to the proper storage method.
1419 sub _rs_update_delete {
1420 my ($self, $op, $values) = @_;
1422 my $rsrc = $self->result_source;
1424 # if a condition exists we need to strip all table qualifiers
1425 # if this is not possible we'll force a subquery below
1426 my $cond = $rsrc->schema->storage->_strip_cond_qualifiers ($self->{cond});
1428 my $needs_group_by_subq = $self->_has_resolved_attr (qw/collapse group_by -join/);
1429 my $needs_subq = $needs_group_by_subq || (not defined $cond) || $self->_has_resolved_attr(qw/rows offset/);
1431 if ($needs_group_by_subq or $needs_subq) {
1433 # make a new $rs selecting only the PKs (that's all we really need)
1434 my $attrs = $self->_resolved_attrs_copy;
1437 delete $attrs->{$_} for qw/collapse _collapse_order_by select _prefetch_select as/;
1438 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->_pri_cols) ];
1440 if ($needs_group_by_subq) {
1441 # make sure no group_by was supplied, or if there is one - make sure it matches
1442 # the columns compiled above perfectly. Anything else can not be sanely executed
1443 # on most databases so croak right then and there
1445 if (my $g = $attrs->{group_by}) {
1446 my @current_group_by = map
1447 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1452 join ("\x00", sort @current_group_by)
1454 join ("\x00", sort @{$attrs->{columns}} )
1456 $self->throw_exception (
1457 "You have just attempted a $op operation on a resultset which does group_by"
1458 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1459 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1460 . ' kind of queries. Please retry the operation with a modified group_by or'
1461 . ' without using one at all.'
1466 $attrs->{group_by} = $attrs->{columns};
1470 my $subrs = (ref $self)->new($rsrc, $attrs);
1471 return $self->result_source->storage->_subq_update_delete($subrs, $op, $values);
1474 return $rsrc->storage->$op(
1476 $op eq 'update' ? $values : (),
1486 =item Arguments: \%values
1488 =item Return Value: $storage_rv
1492 Sets the specified columns in the resultset to the supplied values in a
1493 single query. Return value will be true if the update succeeded or false
1494 if no records were updated; exact type of success value is storage-dependent.
1499 my ($self, $values) = @_;
1500 $self->throw_exception('Values for update must be a hash')
1501 unless ref $values eq 'HASH';
1503 return $self->_rs_update_delete ('update', $values);
1510 =item Arguments: \%values
1512 =item Return Value: 1
1516 Fetches all objects and updates them one at a time. Note that C<update_all>
1517 will run DBIC cascade triggers, while L</update> will not.
1522 my ($self, $values) = @_;
1523 $self->throw_exception('Values for update_all must be a hash')
1524 unless ref $values eq 'HASH';
1526 my $guard = $self->result_source->schema->txn_scope_guard;
1527 $_->update($values) for $self->all;
1536 =item Arguments: none
1538 =item Return Value: $storage_rv
1542 Deletes the contents of the resultset from its result source. Note that this
1543 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1544 to run. See also L<DBIx::Class::Row/delete>.
1546 Return value will be the number of rows deleted; exact type of return value
1547 is storage-dependent.
1553 $self->throw_exception('delete does not accept any arguments')
1556 return $self->_rs_update_delete ('delete');
1563 =item Arguments: none
1565 =item Return Value: 1
1569 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1570 will run DBIC cascade triggers, while L</delete> will not.
1576 $self->throw_exception('delete_all does not accept any arguments')
1579 my $guard = $self->result_source->schema->txn_scope_guard;
1580 $_->delete for $self->all;
1589 =item Arguments: \@data;
1593 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1594 For the arrayref of hashrefs style each hashref should be a structure suitable
1595 forsubmitting to a $resultset->create(...) method.
1597 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1598 to insert the data, as this is a faster method.
1600 Otherwise, each set of data is inserted into the database using
1601 L<DBIx::Class::ResultSet/create>, and the resulting objects are
1602 accumulated into an array. The array itself, or an array reference
1603 is returned depending on scalar or list context.
1605 Example: Assuming an Artist Class that has many CDs Classes relating:
1607 my $Artist_rs = $schema->resultset("Artist");
1609 ## Void Context Example
1610 $Artist_rs->populate([
1611 { artistid => 4, name => 'Manufactured Crap', cds => [
1612 { title => 'My First CD', year => 2006 },
1613 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1616 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1617 { title => 'My parents sold me to a record company', year => 2005 },
1618 { title => 'Why Am I So Ugly?', year => 2006 },
1619 { title => 'I Got Surgery and am now Popular', year => 2007 }
1624 ## Array Context Example
1625 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1626 { name => "Artist One"},
1627 { name => "Artist Two"},
1628 { name => "Artist Three", cds=> [
1629 { title => "First CD", year => 2007},
1630 { title => "Second CD", year => 2008},
1634 print $ArtistOne->name; ## response is 'Artist One'
1635 print $ArtistThree->cds->count ## reponse is '2'
1637 For the arrayref of arrayrefs style, the first element should be a list of the
1638 fieldsnames to which the remaining elements are rows being inserted. For
1641 $Arstist_rs->populate([
1642 [qw/artistid name/],
1643 [100, 'A Formally Unknown Singer'],
1644 [101, 'A singer that jumped the shark two albums ago'],
1645 [102, 'An actually cool singer'],
1648 Please note an important effect on your data when choosing between void and
1649 wantarray context. Since void context goes straight to C<insert_bulk> in
1650 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
1651 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
1652 create primary keys for you, you will find that your PKs are empty. In this
1653 case you will have to use the wantarray context in order to create those
1661 # cruft placed in standalone method
1662 my $data = $self->_normalize_populate_args(@_);
1664 if(defined wantarray) {
1666 foreach my $item (@$data) {
1667 push(@created, $self->create($item));
1669 return wantarray ? @created : \@created;
1671 my $first = $data->[0];
1673 # if a column is a registered relationship, and is a non-blessed hash/array, consider
1674 # it relationship data
1675 my (@rels, @columns);
1676 for (keys %$first) {
1677 my $ref = ref $first->{$_};
1678 $self->result_source->has_relationship($_) && ($ref eq 'ARRAY' or $ref eq 'HASH')
1684 my @pks = $self->result_source->primary_columns;
1686 ## do the belongs_to relationships
1687 foreach my $index (0..$#$data) {
1689 # delegate to create() for any dataset without primary keys with specified relationships
1690 if (grep { !defined $data->[$index]->{$_} } @pks ) {
1692 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
1693 my @ret = $self->populate($data);
1699 foreach my $rel (@rels) {
1700 next unless ref $data->[$index]->{$rel} eq "HASH";
1701 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1702 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1703 my $related = $result->result_source->_resolve_condition(
1704 $result->result_source->relationship_info($reverse)->{cond},
1709 delete $data->[$index]->{$rel};
1710 $data->[$index] = {%{$data->[$index]}, %$related};
1712 push @columns, keys %$related if $index == 0;
1716 ## inherit the data locked in the conditions of the resultset
1717 my ($rs_data) = $self->_merge_cond_with_data({});
1718 delete @{$rs_data}{@columns};
1719 my @inherit_cols = keys %$rs_data;
1720 my @inherit_data = values %$rs_data;
1722 ## do bulk insert on current row
1723 $self->result_source->storage->insert_bulk(
1724 $self->result_source,
1725 [@columns, @inherit_cols],
1726 [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
1729 ## do the has_many relationships
1730 foreach my $item (@$data) {
1732 foreach my $rel (@rels) {
1733 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1735 my $parent = $self->find({map { $_ => $item->{$_} } @pks})
1736 || $self->throw_exception('Cannot find the relating object.');
1738 my $child = $parent->$rel;
1740 my $related = $child->result_source->_resolve_condition(
1741 $parent->result_source->relationship_info($rel)->{cond},
1746 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1747 my @populate = map { {%$_, %$related} } @rows_to_add;
1749 $child->populate( \@populate );
1756 # populate() argumnets went over several incarnations
1757 # What we ultimately support is AoH
1758 sub _normalize_populate_args {
1759 my ($self, $arg) = @_;
1761 if (ref $arg eq 'ARRAY') {
1762 if (ref $arg->[0] eq 'HASH') {
1765 elsif (ref $arg->[0] eq 'ARRAY') {
1767 my @colnames = @{$arg->[0]};
1768 foreach my $values (@{$arg}[1 .. $#$arg]) {
1769 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
1775 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
1782 =item Arguments: none
1784 =item Return Value: $pager
1788 Return Value a L<Data::Page> object for the current resultset. Only makes
1789 sense for queries with a C<page> attribute.
1791 To get the full count of entries for a paged resultset, call
1792 C<total_entries> on the L<Data::Page> object.
1799 return $self->{pager} if $self->{pager};
1801 my $attrs = $self->{attrs};
1802 $self->throw_exception("Can't create pager for non-paged rs")
1803 unless $self->{attrs}{page};
1804 $attrs->{rows} ||= 10;
1806 # throw away the paging flags and re-run the count (possibly
1807 # with a subselect) to get the real total count
1808 my $count_attrs = { %$attrs };
1809 delete $count_attrs->{$_} for qw/rows offset page pager/;
1810 my $total_count = (ref $self)->new($self->result_source, $count_attrs)->count;
1812 return $self->{pager} = Data::Page->new(
1815 $self->{attrs}{page}
1823 =item Arguments: $page_number
1825 =item Return Value: $rs
1829 Returns a resultset for the $page_number page of the resultset on which page
1830 is called, where each page contains a number of rows equal to the 'rows'
1831 attribute set on the resultset (10 by default).
1836 my ($self, $page) = @_;
1837 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1844 =item Arguments: \%vals
1846 =item Return Value: $rowobject
1850 Creates a new row object in the resultset's result class and returns
1851 it. The row is not inserted into the database at this point, call
1852 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
1853 will tell you whether the row object has been inserted or not.
1855 Passes the hashref of input on to L<DBIx::Class::Row/new>.
1860 my ($self, $values) = @_;
1861 $self->throw_exception( "new_result needs a hash" )
1862 unless (ref $values eq 'HASH');
1864 my ($merged_cond, $cols_from_relations) = $self->_merge_cond_with_data($values);
1868 @$cols_from_relations
1869 ? (-cols_from_relations => $cols_from_relations)
1871 -source_handle => $self->_source_handle,
1872 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
1875 return $self->result_class->new(\%new);
1878 # _merge_cond_with_data
1880 # Takes a simple hash of K/V data and returns its copy merged with the
1881 # condition already present on the resultset. Additionally returns an
1882 # arrayref of value/condition names, which were inferred from related
1883 # objects (this is needed for in-memory related objects)
1884 sub _merge_cond_with_data {
1885 my ($self, $data) = @_;
1887 my (%new_data, @cols_from_relations);
1889 my $alias = $self->{attrs}{alias};
1891 if (! defined $self->{cond}) {
1892 # just massage $data below
1894 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
1895 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
1896 @cols_from_relations = keys %new_data;
1898 elsif (ref $self->{cond} ne 'HASH') {
1899 $self->throw_exception(
1900 "Can't abstract implicit construct, resultset condition not a hash"
1904 # precendence must be given to passed values over values inherited from
1905 # the cond, so the order here is important.
1906 my $collapsed_cond = $self->_collapse_cond($self->{cond});
1907 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
1909 while ( my($col, $value) = each %implied ) {
1910 if (ref($value) eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '=') {
1911 $new_data{$col} = $value->{'='};
1914 $new_data{$col} = $value if $self->_is_deterministic_value($value);
1920 %{ $self->_remove_alias($data, $alias) },
1923 return (\%new_data, \@cols_from_relations);
1926 # _is_deterministic_value
1928 # Make an effor to strip non-deterministic values from the condition,
1929 # to make sure new_result chokes less
1931 sub _is_deterministic_value {
1934 my $ref_type = ref $value;
1935 return 1 if $ref_type eq '' || $ref_type eq 'SCALAR';
1936 return 1 if Scalar::Util::blessed($value);
1940 # _has_resolved_attr
1942 # determines if the resultset defines at least one
1943 # of the attributes supplied
1945 # used to determine if a subquery is neccessary
1947 # supports some virtual attributes:
1949 # This will scan for any joins being present on the resultset.
1950 # It is not a mere key-search but a deep inspection of {from}
1953 sub _has_resolved_attr {
1954 my ($self, @attr_names) = @_;
1956 my $attrs = $self->_resolved_attrs;
1960 for my $n (@attr_names) {
1961 if (grep { $n eq $_ } (qw/-join/) ) {
1962 $extra_checks{$n}++;
1966 my $attr = $attrs->{$n};
1968 next if not defined $attr;
1970 if (ref $attr eq 'HASH') {
1971 return 1 if keys %$attr;
1973 elsif (ref $attr eq 'ARRAY') {
1981 # a resolved join is expressed as a multi-level from
1983 $extra_checks{-join}
1985 ref $attrs->{from} eq 'ARRAY'
1987 @{$attrs->{from}} > 1
1995 # Recursively collapse the condition.
1997 sub _collapse_cond {
1998 my ($self, $cond, $collapsed) = @_;
2002 if (ref $cond eq 'ARRAY') {
2003 foreach my $subcond (@$cond) {
2004 next unless ref $subcond; # -or
2005 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2008 elsif (ref $cond eq 'HASH') {
2009 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2010 foreach my $subcond (@{$cond->{-and}}) {
2011 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2015 foreach my $col (keys %$cond) {
2016 my $value = $cond->{$col};
2017 $collapsed->{$col} = $value;
2027 # Remove the specified alias from the specified query hash. A copy is made so
2028 # the original query is not modified.
2031 my ($self, $query, $alias) = @_;
2033 my %orig = %{ $query || {} };
2036 foreach my $key (keys %orig) {
2038 $unaliased{$key} = $orig{$key};
2041 $unaliased{$1} = $orig{$key}
2042 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2052 =item Arguments: none
2054 =item Return Value: \[ $sql, @bind ]
2058 Returns the SQL query and bind vars associated with the invocant.
2060 This is generally used as the RHS for a subquery.
2067 my $attrs = $self->_resolved_attrs_copy;
2072 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2073 # $sql also has no wrapping parenthesis in list ctx
2075 my $sqlbind = $self->result_source->storage
2076 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2085 =item Arguments: \%vals, \%attrs?
2087 =item Return Value: $rowobject
2091 my $artist = $schema->resultset('Artist')->find_or_new(
2092 { artist => 'fred' }, { key => 'artists' });
2094 $cd->cd_to_producer->find_or_new({ producer => $producer },
2095 { key => 'primary });
2097 Find an existing record from this resultset, based on its primary
2098 key, or a unique constraint. If none exists, instantiate a new result
2099 object and return it. The object will not be saved into your storage
2100 until you call L<DBIx::Class::Row/insert> on it.
2102 You most likely want this method when looking for existing rows using
2103 a unique constraint that is not the primary key, or looking for
2106 If you want objects to be saved immediately, use L</find_or_create>
2109 B<Note>: Take care when using C<find_or_new> with a table having
2110 columns with default values that you intend to be automatically
2111 supplied by the database (e.g. an auto_increment primary key column).
2112 In normal usage, the value of such columns should NOT be included at
2113 all in the call to C<find_or_new>, even when set to C<undef>.
2119 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2120 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2121 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2124 return $self->new_result($hash);
2131 =item Arguments: \%vals
2133 =item Return Value: a L<DBIx::Class::Row> $object
2137 Attempt to create a single new row or a row with multiple related rows
2138 in the table represented by the resultset (and related tables). This
2139 will not check for duplicate rows before inserting, use
2140 L</find_or_create> to do that.
2142 To create one row for this resultset, pass a hashref of key/value
2143 pairs representing the columns of the table and the values you wish to
2144 store. If the appropriate relationships are set up, foreign key fields
2145 can also be passed an object representing the foreign row, and the
2146 value will be set to its primary key.
2148 To create related objects, pass a hashref of related-object column values
2149 B<keyed on the relationship name>. If the relationship is of type C<multi>
2150 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2151 The process will correctly identify columns holding foreign keys, and will
2152 transparently populate them from the keys of the corresponding relation.
2153 This can be applied recursively, and will work correctly for a structure
2154 with an arbitrary depth and width, as long as the relationships actually
2155 exists and the correct column data has been supplied.
2158 Instead of hashrefs of plain related data (key/value pairs), you may
2159 also pass new or inserted objects. New objects (not inserted yet, see
2160 L</new>), will be inserted into their appropriate tables.
2162 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2164 Example of creating a new row.
2166 $person_rs->create({
2167 name=>"Some Person",
2168 email=>"somebody@someplace.com"
2171 Example of creating a new row and also creating rows in a related C<has_many>
2172 or C<has_one> resultset. Note Arrayref.
2175 { artistid => 4, name => 'Manufactured Crap', cds => [
2176 { title => 'My First CD', year => 2006 },
2177 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2182 Example of creating a new row and also creating a row in a related
2183 C<belongs_to>resultset. Note Hashref.
2186 title=>"Music for Silly Walks",
2189 name=>"Silly Musician",
2197 When subclassing ResultSet never attempt to override this method. Since
2198 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2199 lot of the internals simply never call it, so your override will be
2200 bypassed more often than not. Override either L<new|DBIx::Class::Row/new>
2201 or L<insert|DBIx::Class::Row/insert> depending on how early in the
2202 L</create> process you need to intervene.
2209 my ($self, $attrs) = @_;
2210 $self->throw_exception( "create needs a hashref" )
2211 unless ref $attrs eq 'HASH';
2212 return $self->new_result($attrs)->insert;
2215 =head2 find_or_create
2219 =item Arguments: \%vals, \%attrs?
2221 =item Return Value: $rowobject
2225 $cd->cd_to_producer->find_or_create({ producer => $producer },
2226 { key => 'primary' });
2228 Tries to find a record based on its primary key or unique constraints; if none
2229 is found, creates one and returns that instead.
2231 my $cd = $schema->resultset('CD')->find_or_create({
2233 artist => 'Massive Attack',
2234 title => 'Mezzanine',
2238 Also takes an optional C<key> attribute, to search by a specific key or unique
2239 constraint. For example:
2241 my $cd = $schema->resultset('CD')->find_or_create(
2243 artist => 'Massive Attack',
2244 title => 'Mezzanine',
2246 { key => 'cd_artist_title' }
2249 B<Note>: Because find_or_create() reads from the database and then
2250 possibly inserts based on the result, this method is subject to a race
2251 condition. Another process could create a record in the table after
2252 the find has completed and before the create has started. To avoid
2253 this problem, use find_or_create() inside a transaction.
2255 B<Note>: Take care when using C<find_or_create> with a table having
2256 columns with default values that you intend to be automatically
2257 supplied by the database (e.g. an auto_increment primary key column).
2258 In normal usage, the value of such columns should NOT be included at
2259 all in the call to C<find_or_create>, even when set to C<undef>.
2261 See also L</find> and L</update_or_create>. For information on how to declare
2262 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2266 sub find_or_create {
2268 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2269 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2270 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2273 return $self->create($hash);
2276 =head2 update_or_create
2280 =item Arguments: \%col_values, { key => $unique_constraint }?
2282 =item Return Value: $rowobject
2286 $resultset->update_or_create({ col => $val, ... });
2288 First, searches for an existing row matching one of the unique constraints
2289 (including the primary key) on the source of this resultset. If a row is
2290 found, updates it with the other given column values. Otherwise, creates a new
2293 Takes an optional C<key> attribute to search on a specific unique constraint.
2296 # In your application
2297 my $cd = $schema->resultset('CD')->update_or_create(
2299 artist => 'Massive Attack',
2300 title => 'Mezzanine',
2303 { key => 'cd_artist_title' }
2306 $cd->cd_to_producer->update_or_create({
2307 producer => $producer,
2314 If no C<key> is specified, it searches on all unique constraints defined on the
2315 source, including the primary key.
2317 If the C<key> is specified as C<primary>, it searches only on the primary key.
2319 See also L</find> and L</find_or_create>. For information on how to declare
2320 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2322 B<Note>: Take care when using C<update_or_create> with a table having
2323 columns with default values that you intend to be automatically
2324 supplied by the database (e.g. an auto_increment primary key column).
2325 In normal usage, the value of such columns should NOT be included at
2326 all in the call to C<update_or_create>, even when set to C<undef>.
2330 sub update_or_create {
2332 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2333 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2335 my $row = $self->find($cond, $attrs);
2337 $row->update($cond);
2341 return $self->create($cond);
2344 =head2 update_or_new
2348 =item Arguments: \%col_values, { key => $unique_constraint }?
2350 =item Return Value: $rowobject
2354 $resultset->update_or_new({ col => $val, ... });
2356 First, searches for an existing row matching one of the unique constraints
2357 (including the primary key) on the source of this resultset. If a row is
2358 found, updates it with the other given column values. Otherwise, instantiate
2359 a new result object and return it. The object will not be saved into your storage
2360 until you call L<DBIx::Class::Row/insert> on it.
2362 Takes an optional C<key> attribute to search on a specific unique constraint.
2365 # In your application
2366 my $cd = $schema->resultset('CD')->update_or_new(
2368 artist => 'Massive Attack',
2369 title => 'Mezzanine',
2372 { key => 'cd_artist_title' }
2375 if ($cd->in_storage) {
2376 # the cd was updated
2379 # the cd is not yet in the database, let's insert it
2383 B<Note>: Take care when using C<update_or_new> with a table having
2384 columns with default values that you intend to be automatically
2385 supplied by the database (e.g. an auto_increment primary key column).
2386 In normal usage, the value of such columns should NOT be included at
2387 all in the call to C<update_or_new>, even when set to C<undef>.
2389 See also L</find>, L</find_or_create> and L</find_or_new>.
2395 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2396 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2398 my $row = $self->find( $cond, $attrs );
2399 if ( defined $row ) {
2400 $row->update($cond);
2404 return $self->new_result($cond);
2411 =item Arguments: none
2413 =item Return Value: \@cache_objects?
2417 Gets the contents of the cache for the resultset, if the cache is set.
2419 The cache is populated either by using the L</prefetch> attribute to
2420 L</search> or by calling L</set_cache>.
2432 =item Arguments: \@cache_objects
2434 =item Return Value: \@cache_objects
2438 Sets the contents of the cache for the resultset. Expects an arrayref
2439 of objects of the same class as those produced by the resultset. Note that
2440 if the cache is set the resultset will return the cached objects rather
2441 than re-querying the database even if the cache attr is not set.
2443 The contents of the cache can also be populated by using the
2444 L</prefetch> attribute to L</search>.
2449 my ( $self, $data ) = @_;
2450 $self->throw_exception("set_cache requires an arrayref")
2451 if defined($data) && (ref $data ne 'ARRAY');
2452 $self->{all_cache} = $data;
2459 =item Arguments: none
2461 =item Return Value: []
2465 Clears the cache for the resultset.
2470 shift->set_cache(undef);
2477 =item Arguments: none
2479 =item Return Value: true, if the resultset has been paginated
2487 return !!$self->{attrs}{page};
2494 =item Arguments: none
2496 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2504 return scalar $self->result_source->storage->_parse_order_by($self->{attrs}{order_by});
2507 =head2 related_resultset
2511 =item Arguments: $relationship_name
2513 =item Return Value: $resultset
2517 Returns a related resultset for the supplied relationship name.
2519 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2523 sub related_resultset {
2524 my ($self, $rel) = @_;
2526 $self->{related_resultsets} ||= {};
2527 return $self->{related_resultsets}{$rel} ||= do {
2528 my $rsrc = $self->result_source;
2529 my $rel_info = $rsrc->relationship_info($rel);
2531 $self->throw_exception(
2532 "search_related: result source '" . $rsrc->source_name .
2533 "' has no such relationship $rel")
2536 my $attrs = $self->_chain_relationship($rel);
2538 my $join_count = $attrs->{seen_join}{$rel};
2540 my $alias = $self->result_source->storage
2541 ->relname_to_table_alias($rel, $join_count);
2543 # since this is search_related, and we already slid the select window inwards
2544 # (the select/as attrs were deleted in the beginning), we need to flip all
2545 # left joins to inner, so we get the expected results
2546 # read the comment on top of the actual function to see what this does
2547 $attrs->{from} = $rsrc->schema->storage->_straight_join_to_node ($attrs->{from}, $alias);
2550 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2551 delete @{$attrs}{qw(result_class alias)};
2555 if (my $cache = $self->get_cache) {
2556 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2557 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
2562 my $rel_source = $rsrc->related_source($rel);
2566 # The reason we do this now instead of passing the alias to the
2567 # search_rs below is that if you wrap/overload resultset on the
2568 # source you need to know what alias it's -going- to have for things
2569 # to work sanely (e.g. RestrictWithObject wants to be able to add
2570 # extra query restrictions, and these may need to be $alias.)
2572 my $rel_attrs = $rel_source->resultset_attributes;
2573 local $rel_attrs->{alias} = $alias;
2575 $rel_source->resultset
2579 where => $attrs->{where},
2582 $new->set_cache($new_cache) if $new_cache;
2587 =head2 current_source_alias
2591 =item Arguments: none
2593 =item Return Value: $source_alias
2597 Returns the current table alias for the result source this resultset is built
2598 on, that will be used in the SQL query. Usually it is C<me>.
2600 Currently the source alias that refers to the result set returned by a
2601 L</search>/L</find> family method depends on how you got to the resultset: it's
2602 C<me> by default, but eg. L</search_related> aliases it to the related result
2603 source name (and keeps C<me> referring to the original result set). The long
2604 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
2605 (and make this method unnecessary).
2607 Thus it's currently necessary to use this method in predefined queries (see
2608 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
2609 source alias of the current result set:
2611 # in a result set class
2613 my ($self, $user) = @_;
2615 my $me = $self->current_source_alias;
2617 return $self->search(
2618 "$me.modified" => $user->id,
2624 sub current_source_alias {
2627 return ($self->{attrs} || {})->{alias} || 'me';
2630 =head2 as_subselect_rs
2634 =item Arguments: none
2636 =item Return Value: $resultset
2640 Act as a barrier to SQL symbols. The resultset provided will be made into a
2641 "virtual view" by including it as a subquery within the from clause. From this
2642 point on, any joined tables are inaccessible to ->search on the resultset (as if
2643 it were simply where-filtered without joins). For example:
2645 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
2647 # 'x' now pollutes the query namespace
2649 # So the following works as expected
2650 my $ok_rs = $rs->search({'x.other' => 1});
2652 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
2653 # def) we look for one row with contradictory terms and join in another table
2654 # (aliased 'x_2') which we never use
2655 my $broken_rs = $rs->search({'x.name' => 'def'});
2657 my $rs2 = $rs->as_subselect_rs;
2659 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
2660 my $not_joined_rs = $rs2->search({'x.other' => 1});
2662 # works as expected: finds a 'table' row related to two x rows (abc and def)
2663 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
2665 Another example of when one might use this would be to select a subset of
2666 columns in a group by clause:
2668 my $rs = $schema->resultset('Bar')->search(undef, {
2669 group_by => [qw{ id foo_id baz_id }],
2670 })->as_subselect_rs->search(undef, {
2671 columns => [qw{ id foo_id }]
2674 In the above example normally columns would have to be equal to the group by,
2675 but because we isolated the group by into a subselect the above works.
2679 sub as_subselect_rs {
2682 my $attrs = $self->_resolved_attrs;
2684 my $fresh_rs = (ref $self)->new (
2685 $self->result_source
2688 # these pieces will be locked in the subquery
2689 delete $fresh_rs->{cond};
2690 delete @{$fresh_rs->{attrs}}{qw/where bind/};
2692 return $fresh_rs->search( {}, {
2694 $attrs->{alias} => $self->as_query,
2695 -alias => $attrs->{alias},
2696 -source_handle => $self->result_source->handle,
2698 alias => $attrs->{alias},
2702 # This code is called by search_related, and makes sure there
2703 # is clear separation between the joins before, during, and
2704 # after the relationship. This information is needed later
2705 # in order to properly resolve prefetch aliases (any alias
2706 # with a relation_chain_depth less than the depth of the
2707 # current prefetch is not considered)
2709 # The increments happen twice per join. An even number means a
2710 # relationship specified via a search_related, whereas an odd
2711 # number indicates a join/prefetch added via attributes
2713 # Also this code will wrap the current resultset (the one we
2714 # chain to) in a subselect IFF it contains limiting attributes
2715 sub _chain_relationship {
2716 my ($self, $rel) = @_;
2717 my $source = $self->result_source;
2718 my $attrs = { %{$self->{attrs}||{}} };
2720 # we need to take the prefetch the attrs into account before we
2721 # ->_resolve_join as otherwise they get lost - captainL
2722 my $join = $self->_merge_attr( $attrs->{join}, $attrs->{prefetch} );
2724 delete @{$attrs}{qw/join prefetch collapse group_by distinct select as columns +select +as +columns/};
2726 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
2729 my @force_subq_attrs = qw/offset rows group_by having/;
2732 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
2734 $self->_has_resolved_attr (@force_subq_attrs)
2736 # Nuke the prefetch (if any) before the new $rs attrs
2737 # are resolved (prefetch is useless - we are wrapping
2738 # a subquery anyway).
2739 my $rs_copy = $self->search;
2740 $rs_copy->{attrs}{join} = $self->_merge_attr (
2741 $rs_copy->{attrs}{join},
2742 delete $rs_copy->{attrs}{prefetch},
2746 -source_handle => $source->handle,
2747 -alias => $attrs->{alias},
2748 $attrs->{alias} => $rs_copy->as_query,
2750 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
2751 $seen->{-relation_chain_depth} = 0;
2753 elsif ($attrs->{from}) { #shallow copy suffices
2754 $from = [ @{$attrs->{from}} ];
2758 -source_handle => $source->handle,
2759 -alias => $attrs->{alias},
2760 $attrs->{alias} => $source->from,
2764 my $jpath = ($seen->{-relation_chain_depth})
2765 ? $from->[-1][0]{-join_path}
2768 my @requested_joins = $source->_resolve_join(
2775 push @$from, @requested_joins;
2777 $seen->{-relation_chain_depth}++;
2779 # if $self already had a join/prefetch specified on it, the requested
2780 # $rel might very well be already included. What we do in this case
2781 # is effectively a no-op (except that we bump up the chain_depth on
2782 # the join in question so we could tell it *is* the search_related)
2785 # we consider the last one thus reverse
2786 for my $j (reverse @requested_joins) {
2787 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
2788 if ($rel eq $last_j) {
2789 $j->[0]{-relation_chain_depth}++;
2795 unless ($already_joined) {
2796 push @$from, $source->_resolve_join(
2804 $seen->{-relation_chain_depth}++;
2806 return {%$attrs, from => $from, seen_join => $seen};
2809 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
2810 sub _resolved_attrs_copy {
2812 return { %{$self->_resolved_attrs (@_)} };
2815 sub _resolved_attrs {
2817 return $self->{_attrs} if $self->{_attrs};
2819 my $attrs = { %{ $self->{attrs} || {} } };
2820 my $source = $self->result_source;
2821 my $alias = $attrs->{alias};
2823 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
2826 # build columns (as long as select isn't set) into a set of as/select hashes
2827 unless ( $attrs->{select} ) {
2830 if ( ref $attrs->{columns} eq 'ARRAY' ) {
2831 @cols = @{ delete $attrs->{columns}}
2832 } elsif ( defined $attrs->{columns} ) {
2833 @cols = delete $attrs->{columns}
2835 @cols = $source->columns
2839 if ( ref $_ eq 'HASH' ) {
2842 my $key = /^\Q${alias}.\E(.+)$/
2848 push @colbits, { $key => $value };
2853 # add the additional columns on
2854 foreach (qw{include_columns +columns}) {
2855 if ( $attrs->{$_} ) {
2856 my @list = ( ref($attrs->{$_}) eq 'ARRAY' )
2857 ? @{ delete $attrs->{$_} }
2858 : delete $attrs->{$_};
2860 if ( ref($_) eq 'HASH' ) {
2863 my $key = ( split /\./, $_ )[-1];
2864 my $value = ( /\./ ? $_ : "$alias.$_" );
2865 push @colbits, { $key => $value };
2871 # start with initial select items
2872 if ( $attrs->{select} ) {
2874 ( ref $attrs->{select} eq 'ARRAY' )
2875 ? [ @{ $attrs->{select} } ]
2876 : [ $attrs->{select} ];
2878 if ( $attrs->{as} ) {
2881 ref $attrs->{as} eq 'ARRAY'
2882 ? [ @{ $attrs->{as} } ]
2886 $attrs->{as} = [ map {
2887 m/^\Q${alias}.\E(.+)$/
2890 } @{ $attrs->{select} }
2896 # otherwise we intialise select & as to empty
2897 $attrs->{select} = [];
2901 # now add colbits to select/as
2902 push @{ $attrs->{select} }, map values %{$_}, @colbits;
2903 push @{ $attrs->{as} }, map keys %{$_}, @colbits;
2905 if ( my $adds = delete $attrs->{'+select'} ) {
2906 $adds = [$adds] unless ref $adds eq 'ARRAY';
2907 push @{ $attrs->{select} },
2908 map { /\./ || ref $_ ? $_ : "$alias.$_" } @$adds;
2910 if ( my $adds = delete $attrs->{'+as'} ) {
2911 $adds = [$adds] unless ref $adds eq 'ARRAY';
2912 push @{ $attrs->{as} }, @$adds;
2915 $attrs->{from} ||= [{
2916 -source_handle => $source->handle,
2917 -alias => $self->{attrs}{alias},
2918 $self->{attrs}{alias} => $source->from,
2921 if ( $attrs->{join} || $attrs->{prefetch} ) {
2923 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
2924 if ref $attrs->{from} ne 'ARRAY';
2926 my $join = delete $attrs->{join} || {};
2928 if ( defined $attrs->{prefetch} ) {
2929 $join = $self->_merge_attr( $join, $attrs->{prefetch} );
2932 $attrs->{from} = # have to copy here to avoid corrupting the original
2934 @{ $attrs->{from} },
2935 $source->_resolve_join(
2938 { %{ $attrs->{seen_join} || {} } },
2939 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
2940 ? $attrs->{from}[-1][0]{-join_path}
2947 if ( defined $attrs->{order_by} ) {
2948 $attrs->{order_by} = (
2949 ref( $attrs->{order_by} ) eq 'ARRAY'
2950 ? [ @{ $attrs->{order_by} } ]
2951 : [ $attrs->{order_by} || () ]
2955 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
2956 $attrs->{group_by} = [ $attrs->{group_by} ];
2959 # generate the distinct induced group_by early, as prefetch will be carried via a
2960 # subquery (since a group_by is present)
2961 if (delete $attrs->{distinct}) {
2962 if ($attrs->{group_by}) {
2963 carp ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
2966 $attrs->{group_by} = [ grep { !ref($_) || (ref($_) ne 'HASH') } @{$attrs->{select}} ];
2968 # add any order_by parts that are not already present in the group_by
2969 # we need to be careful not to add any named functions/aggregates
2970 # i.e. select => [ ... { count => 'foo', -as 'foocount' } ... ]
2971 my %already_grouped = map { $_ => 1 } (@{$attrs->{group_by}});
2973 my $storage = $self->result_source->schema->storage;
2975 my $rs_column_list = $storage->_resolve_column_info ($attrs->{from});
2977 for my $chunk ($storage->_parse_order_by($attrs->{order_by})) {
2978 if ($rs_column_list->{$chunk} && not $already_grouped{$chunk}++) {
2979 push @{$attrs->{group_by}}, $chunk;
2985 $attrs->{collapse} ||= {};
2986 if ( my $prefetch = delete $attrs->{prefetch} ) {
2987 $prefetch = $self->_merge_attr( {}, $prefetch );
2989 my $prefetch_ordering = [];
2991 # this is a separate structure (we don't look in {from} directly)
2992 # as the resolver needs to shift things off the lists to work
2993 # properly (identical-prefetches on different branches)
2995 if (ref $attrs->{from} eq 'ARRAY') {
2997 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
2999 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3000 next unless $j->[0]{-alias};
3001 next unless $j->[0]{-join_path};
3002 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3004 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3007 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3008 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3013 $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
3015 # we need to somehow mark which columns came from prefetch
3016 $attrs->{_prefetch_select} = [ map { $_->[0] } @prefetch ];
3018 push @{ $attrs->{select} }, @{$attrs->{_prefetch_select}};
3019 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
3021 push( @{$attrs->{order_by}}, @$prefetch_ordering );
3022 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
3025 # if both page and offset are specified, produce a combined offset
3026 # even though it doesn't make much sense, this is what pre 081xx has
3028 if (my $page = delete $attrs->{page}) {
3030 ($attrs->{rows} * ($page - 1))
3032 ($attrs->{offset} || 0)
3036 return $self->{_attrs} = $attrs;
3040 my ($self, $attr) = @_;
3042 if (ref $attr eq 'HASH') {
3043 return $self->_rollout_hash($attr);
3044 } elsif (ref $attr eq 'ARRAY') {
3045 return $self->_rollout_array($attr);
3051 sub _rollout_array {
3052 my ($self, $attr) = @_;
3055 foreach my $element (@{$attr}) {
3056 if (ref $element eq 'HASH') {
3057 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3058 } elsif (ref $element eq 'ARRAY') {
3059 # XXX - should probably recurse here
3060 push( @rolled_array, @{$self->_rollout_array($element)} );
3062 push( @rolled_array, $element );
3065 return \@rolled_array;
3069 my ($self, $attr) = @_;
3072 foreach my $key (keys %{$attr}) {
3073 push( @rolled_array, { $key => $attr->{$key} } );
3075 return \@rolled_array;
3078 sub _calculate_score {
3079 my ($self, $a, $b) = @_;
3081 if (defined $a xor defined $b) {
3084 elsif (not defined $a) {
3088 if (ref $b eq 'HASH') {
3089 my ($b_key) = keys %{$b};
3090 if (ref $a eq 'HASH') {
3091 my ($a_key) = keys %{$a};
3092 if ($a_key eq $b_key) {
3093 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3098 return ($a eq $b_key) ? 1 : 0;
3101 if (ref $a eq 'HASH') {
3102 my ($a_key) = keys %{$a};
3103 return ($b eq $a_key) ? 1 : 0;
3105 return ($b eq $a) ? 1 : 0;
3111 my ($self, $orig, $import) = @_;
3113 return $import unless defined($orig);
3114 return $orig unless defined($import);
3116 $orig = $self->_rollout_attr($orig);
3117 $import = $self->_rollout_attr($import);
3120 foreach my $import_element ( @{$import} ) {
3121 # find best candidate from $orig to merge $b_element into
3122 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3123 foreach my $orig_element ( @{$orig} ) {
3124 my $score = $self->_calculate_score( $orig_element, $import_element );
3125 if ($score > $best_candidate->{score}) {
3126 $best_candidate->{position} = $position;
3127 $best_candidate->{score} = $score;
3131 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3133 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3134 push( @{$orig}, $import_element );
3136 my $orig_best = $orig->[$best_candidate->{position}];
3137 # merge orig_best and b_element together and replace original with merged
3138 if (ref $orig_best ne 'HASH') {
3139 $orig->[$best_candidate->{position}] = $import_element;
3140 } elsif (ref $import_element eq 'HASH') {
3141 my ($key) = keys %{$orig_best};
3142 $orig->[$best_candidate->{position}] = { $key => $self->_merge_attr($orig_best->{$key}, $import_element->{$key}) };
3145 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3155 $self->_source_handle($_[0]->handle);
3157 $self->_source_handle->resolve;
3161 =head2 throw_exception
3163 See L<DBIx::Class::Schema/throw_exception> for details.
3167 sub throw_exception {
3170 if (ref $self && $self->_source_handle->schema) {
3171 $self->_source_handle->schema->throw_exception(@_)
3174 DBIx::Class::Exception->throw(@_);
3178 # XXX: FIXME: Attributes docs need clearing up
3182 Attributes are used to refine a ResultSet in various ways when
3183 searching for data. They can be passed to any method which takes an
3184 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3187 These are in no particular order:
3193 =item Value: ( $order_by | \@order_by | \%order_by )
3197 Which column(s) to order the results by.
3199 [The full list of suitable values is documented in
3200 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3203 If a single column name, or an arrayref of names is supplied, the
3204 argument is passed through directly to SQL. The hashref syntax allows
3205 for connection-agnostic specification of ordering direction:
3207 For descending order:
3209 order_by => { -desc => [qw/col1 col2 col3/] }
3211 For explicit ascending order:
3213 order_by => { -asc => 'col' }
3215 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3216 supported, although you are strongly encouraged to use the hashref
3217 syntax as outlined above.
3223 =item Value: \@columns
3227 Shortcut to request a particular set of columns to be retrieved. Each
3228 column spec may be a string (a table column name), or a hash (in which
3229 case the key is the C<as> value, and the value is used as the C<select>
3230 expression). Adds C<me.> onto the start of any column without a C<.> in
3231 it and sets C<select> from that, then auto-populates C<as> from
3232 C<select> as normal. (You may also use the C<cols> attribute, as in
3233 earlier versions of DBIC.)
3239 =item Value: \@columns
3243 Indicates additional columns to be selected from storage. Works the same
3244 as L</columns> but adds columns to the selection. (You may also use the
3245 C<include_columns> attribute, as in earlier versions of DBIC). For
3248 $schema->resultset('CD')->search(undef, {
3249 '+columns' => ['artist.name'],
3253 would return all CDs and include a 'name' column to the information
3254 passed to object inflation. Note that the 'artist' is the name of the
3255 column (or relationship) accessor, and 'name' is the name of the column
3256 accessor in the related table.
3258 =head2 include_columns
3262 =item Value: \@columns
3266 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3272 =item Value: \@select_columns
3276 Indicates which columns should be selected from the storage. You can use
3277 column names, or in the case of RDBMS back ends, function or stored procedure
3280 $rs = $schema->resultset('Employee')->search(undef, {
3283 { count => 'employeeid' },
3284 { max => { length => 'name' }, -as => 'longest_name' }
3289 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
3291 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
3292 use L</select>, to instruct DBIx::Class how to store the result of the column.
3293 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
3294 identifier aliasing. You can however alias a function, so you can use it in
3295 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
3296 attribute> supplied as shown in the example above.
3302 Indicates additional columns to be selected from storage. Works the same as
3303 L</select> but adds columns to the default selection, instead of specifying
3312 Indicates additional column names for those added via L</+select>. See L</as>.
3320 =item Value: \@inflation_names
3324 Indicates column names for object inflation. That is L</as> indicates the
3325 slot name in which the column value will be stored within the
3326 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
3327 identifier by the C<get_column> method (or via the object accessor B<if one
3328 with the same name already exists>) as shown below. The L</as> attribute has
3329 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
3331 $rs = $schema->resultset('Employee')->search(undef, {
3334 { count => 'employeeid' },
3335 { max => { length => 'name' }, -as => 'longest_name' }
3344 If the object against which the search is performed already has an accessor
3345 matching a column name specified in C<as>, the value can be retrieved using
3346 the accessor as normal:
3348 my $name = $employee->name();
3350 If on the other hand an accessor does not exist in the object, you need to
3351 use C<get_column> instead:
3353 my $employee_count = $employee->get_column('employee_count');
3355 You can create your own accessors if required - see
3356 L<DBIx::Class::Manual::Cookbook> for details.
3362 =item Value: ($rel_name | \@rel_names | \%rel_names)
3366 Contains a list of relationships that should be joined for this query. For
3369 # Get CDs by Nine Inch Nails
3370 my $rs = $schema->resultset('CD')->search(
3371 { 'artist.name' => 'Nine Inch Nails' },
3372 { join => 'artist' }
3375 Can also contain a hash reference to refer to the other relation's relations.
3378 package MyApp::Schema::Track;
3379 use base qw/DBIx::Class/;
3380 __PACKAGE__->table('track');
3381 __PACKAGE__->add_columns(qw/trackid cd position title/);
3382 __PACKAGE__->set_primary_key('trackid');
3383 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3386 # In your application
3387 my $rs = $schema->resultset('Artist')->search(
3388 { 'track.title' => 'Teardrop' },
3390 join => { cd => 'track' },
3391 order_by => 'artist.name',
3395 You need to use the relationship (not the table) name in conditions,
3396 because they are aliased as such. The current table is aliased as "me", so
3397 you need to use me.column_name in order to avoid ambiguity. For example:
3399 # Get CDs from 1984 with a 'Foo' track
3400 my $rs = $schema->resultset('CD')->search(
3403 'tracks.name' => 'Foo'
3405 { join => 'tracks' }
3408 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3409 similarly for a third time). For e.g.
3411 my $rs = $schema->resultset('Artist')->search({
3412 'cds.title' => 'Down to Earth',
3413 'cds_2.title' => 'Popular',
3415 join => [ qw/cds cds/ ],
3418 will return a set of all artists that have both a cd with title 'Down
3419 to Earth' and a cd with title 'Popular'.
3421 If you want to fetch related objects from other tables as well, see C<prefetch>
3424 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3430 =item Value: ($rel_name | \@rel_names | \%rel_names)
3434 Contains one or more relationships that should be fetched along with
3435 the main query (when they are accessed afterwards the data will
3436 already be available, without extra queries to the database). This is
3437 useful for when you know you will need the related objects, because it
3438 saves at least one query:
3440 my $rs = $schema->resultset('Tag')->search(
3449 The initial search results in SQL like the following:
3451 SELECT tag.*, cd.*, artist.* FROM tag
3452 JOIN cd ON tag.cd = cd.cdid
3453 JOIN artist ON cd.artist = artist.artistid
3455 L<DBIx::Class> has no need to go back to the database when we access the
3456 C<cd> or C<artist> relationships, which saves us two SQL statements in this
3459 Simple prefetches will be joined automatically, so there is no need
3460 for a C<join> attribute in the above search.
3462 C<prefetch> can be used with the following relationship types: C<belongs_to>,
3463 C<has_one> (or if you're using C<add_relationship>, any relationship declared
3464 with an accessor type of 'single' or 'filter'). A more complex example that
3465 prefetches an artists cds, the tracks on those cds, and the tags associated
3466 with that artist is given below (assuming many-to-many from artists to tags):
3468 my $rs = $schema->resultset('Artist')->search(
3472 { cds => 'tracks' },
3473 { artist_tags => 'tags' }
3479 B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
3480 attributes will be ignored.
3482 B<CAVEATs>: Prefetch does a lot of deep magic. As such, it may not behave
3483 exactly as you might expect.
3489 Prefetch uses the L</cache> to populate the prefetched relationships. This
3490 may or may not be what you want.
3494 If you specify a condition on a prefetched relationship, ONLY those
3495 rows that match the prefetched condition will be fetched into that relationship.
3496 This means that adding prefetch to a search() B<may alter> what is returned by
3497 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
3499 my $artist_rs = $schema->resultset('Artist')->search({
3505 my $count = $artist_rs->first->cds->count;
3507 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
3509 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
3511 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
3513 that cmp_ok() may or may not pass depending on the datasets involved. This
3514 behavior may or may not survive the 0.09 transition.
3526 Makes the resultset paged and specifies the page to retrieve. Effectively
3527 identical to creating a non-pages resultset and then calling ->page($page)
3530 If L<rows> attribute is not specified it defaults to 10 rows per page.
3532 When you have a paged resultset, L</count> will only return the number
3533 of rows in the page. To get the total, use the L</pager> and call
3534 C<total_entries> on it.
3544 Specifies the maximum number of rows for direct retrieval or the number of
3545 rows per page if the page attribute or method is used.
3551 =item Value: $offset
3555 Specifies the (zero-based) row number for the first row to be returned, or the
3556 of the first row of the first page if paging is used.
3562 =item Value: \@columns
3566 A arrayref of columns to group by. Can include columns of joined tables.
3568 group_by => [qw/ column1 column2 ... /]
3574 =item Value: $condition
3578 HAVING is a select statement attribute that is applied between GROUP BY and
3579 ORDER BY. It is applied to the after the grouping calculations have been
3582 having => { 'count(employee)' => { '>=', 100 } }
3588 =item Value: (0 | 1)
3592 Set to 1 to group by all columns. If the resultset already has a group_by
3593 attribute, this setting is ignored and an appropriate warning is issued.
3599 Adds to the WHERE clause.
3601 # only return rows WHERE deleted IS NULL for all searches
3602 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
3604 Can be overridden by passing C<< { where => undef } >> as an attribute
3611 Set to 1 to cache search results. This prevents extra SQL queries if you
3612 revisit rows in your ResultSet:
3614 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
3616 while( my $artist = $resultset->next ) {
3620 $rs->first; # without cache, this would issue a query
3622 By default, searches are not cached.
3624 For more examples of using these attributes, see
3625 L<DBIx::Class::Manual::Cookbook>.
3631 =item Value: ( 'update' | 'shared' )
3635 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT