1 package DBIx::Class::ResultSet;
5 use base qw/DBIx::Class/;
6 use Carp::Clan qw/^DBIx::Class/;
7 use DBIx::Class::Exception;
10 use DBIx::Class::ResultSetColumn;
11 use DBIx::Class::ResultSourceHandle;
13 use Scalar::Util 'blessed';
21 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class _source_handle/);
25 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
29 my $users_rs = $schema->resultset('User');
30 while( $user = $users_rs->next) {
31 print $user->username;
34 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
35 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
39 A ResultSet is an object which stores a set of conditions representing
40 a query. It is the backbone of DBIx::Class (i.e. the really
41 important/useful bit).
43 No SQL is executed on the database when a ResultSet is created, it
44 just stores all the conditions needed to create the query.
46 A basic ResultSet representing the data of an entire table is returned
47 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
48 L<Source|DBIx::Class::Manual::Glossary/Source> name.
50 my $users_rs = $schema->resultset('User');
52 A new ResultSet is returned from calling L</search> on an existing
53 ResultSet. The new one will contain all the conditions of the
54 original, plus any new conditions added in the C<search> call.
56 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
57 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
60 The query that the ResultSet represents is B<only> executed against
61 the database when these methods are called:
62 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
64 If a resultset is used in a numeric context it returns the L</count>.
65 However, if it is used in a boolean context it is B<always> true. So if
66 you want to check if a resultset has any results, you must use C<if $rs
71 =head2 Chaining resultsets
73 Let's say you've got a query that needs to be run to return some data
74 to the user. But, you have an authorization system in place that
75 prevents certain users from seeing certain information. So, you want
76 to construct the basic query in one method, but add constraints to it in
81 my $request = $self->get_request; # Get a request object somehow.
82 my $schema = $self->get_schema; # Get the DBIC schema object somehow.
84 my $cd_rs = $schema->resultset('CD')->search({
85 title => $request->param('title'),
86 year => $request->param('year'),
89 $self->apply_security_policy( $cd_rs );
94 sub apply_security_policy {
103 =head3 Resolving conditions and attributes
105 When a resultset is chained from another resultset, conditions and
106 attributes with the same keys need resolving.
108 L</join>, L</prefetch>, L</+select>, L</+as> attributes are merged
109 into the existing ones from the original resultset.
111 The L</where> and L</having> attributes, and any search conditions, are
112 merged with an SQL C<AND> to the existing condition from the original
115 All other attributes are overridden by any new ones supplied in the
118 =head2 Multiple queries
120 Since a resultset just defines a query, you can do all sorts of
121 things with it with the same object.
123 # Don't hit the DB yet.
124 my $cd_rs = $schema->resultset('CD')->search({
125 title => 'something',
129 # Each of these hits the DB individually.
130 my $count = $cd_rs->count;
131 my $most_recent = $cd_rs->get_column('date_released')->max();
132 my @records = $cd_rs->all;
134 And it's not just limited to SELECT statements.
140 $cd_rs->create({ artist => 'Fred' });
142 Which is the same as:
144 $schema->resultset('CD')->create({
145 title => 'something',
150 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
158 =item Arguments: $source, \%$attrs
160 =item Return Value: $rs
164 The resultset constructor. Takes a source object (usually a
165 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
166 L</ATTRIBUTES> below). Does not perform any queries -- these are
167 executed as needed by the other methods.
169 Generally you won't need to construct a resultset manually. You'll
170 automatically get one from e.g. a L</search> called in scalar context:
172 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
174 IMPORTANT: If called on an object, proxies to new_result instead so
176 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
178 will return a CD object, not a ResultSet.
184 return $class->new_result(@_) if ref $class;
186 my ($source, $attrs) = @_;
187 $source = $source->handle
188 unless $source->isa('DBIx::Class::ResultSourceHandle');
189 $attrs = { %{$attrs||{}} };
191 if ($attrs->{page}) {
192 $attrs->{rows} ||= 10;
195 $attrs->{alias} ||= 'me';
197 # Creation of {} and bless separated to mitigate RH perl bug
198 # see https://bugzilla.redhat.com/show_bug.cgi?id=196836
200 _source_handle => $source,
201 cond => $attrs->{where},
209 $attrs->{result_class} || $source->resolve->result_class
219 =item Arguments: $cond, \%attrs?
221 =item Return Value: $resultset (scalar context), @row_objs (list context)
225 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
226 my $new_rs = $cd_rs->search({ year => 2005 });
228 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
229 # year = 2005 OR year = 2004
231 If you need to pass in additional attributes but no additional condition,
232 call it as C<search(undef, \%attrs)>.
234 # "SELECT name, artistid FROM $artist_table"
235 my @all_artists = $schema->resultset('Artist')->search(undef, {
236 columns => [qw/name artistid/],
239 For a list of attributes that can be passed to C<search>, see
240 L</ATTRIBUTES>. For more examples of using this function, see
241 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
242 documentation for the first argument, see L<SQL::Abstract>.
244 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
250 my $rs = $self->search_rs( @_ );
251 return (wantarray ? $rs->all : $rs);
258 =item Arguments: $cond, \%attrs?
260 =item Return Value: $resultset
264 This method does the same exact thing as search() except it will
265 always return a resultset, even in list context.
272 # Special-case handling for (undef, undef).
273 if ( @_ == 2 && !defined $_[1] && !defined $_[0] ) {
278 $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
279 my $our_attrs = { %{$self->{attrs}} };
280 my $having = delete $our_attrs->{having};
281 my $where = delete $our_attrs->{where};
285 my %safe = (alias => 1, cache => 1);
288 (@_ && defined($_[0])) # @_ == () or (undef)
290 (keys %$attrs # empty attrs or only 'safe' attrs
291 && List::Util::first { !$safe{$_} } keys %$attrs)
293 # no search, effectively just a clone
294 $rows = $self->get_cache;
297 # reset the selector list
298 if (List::Util::first { exists $attrs->{$_} } qw{columns select as}) {
299 delete @{$our_attrs}{qw{select as columns +select +as +columns include_columns}};
302 my $new_attrs = { %{$our_attrs}, %{$attrs} };
304 # merge new attrs into inherited
305 foreach my $key (qw/join prefetch +select +as +columns include_columns bind/) {
306 next unless exists $attrs->{$key};
307 $new_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key});
312 (@_ == 1 || ref $_[0] eq "HASH")
314 (ref $_[0] eq 'HASH')
316 (keys %{ $_[0] } > 0)
324 ? $self->throw_exception("Odd number of arguments to search")
331 if (defined $where) {
332 $new_attrs->{where} = (
333 defined $new_attrs->{where}
336 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
337 } $where, $new_attrs->{where}
344 $new_attrs->{where} = (
345 defined $new_attrs->{where}
348 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
349 } $cond, $new_attrs->{where}
355 if (defined $having) {
356 $new_attrs->{having} = (
357 defined $new_attrs->{having}
360 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
361 } $having, $new_attrs->{having}
367 my $rs = (ref $self)->new($self->result_source, $new_attrs);
369 $rs->set_cache($rows) if ($rows);
374 =head2 search_literal
378 =item Arguments: $sql_fragment, @bind_values
380 =item Return Value: $resultset (scalar context), @row_objs (list context)
384 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
385 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
387 Pass a literal chunk of SQL to be added to the conditional part of the
390 CAVEAT: C<search_literal> is provided for Class::DBI compatibility and should
391 only be used in that context. C<search_literal> is a convenience method.
392 It is equivalent to calling $schema->search(\[]), but if you want to ensure
393 columns are bound correctly, use C<search>.
395 Example of how to use C<search> instead of C<search_literal>
397 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
398 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
401 See L<DBIx::Class::Manual::Cookbook/Searching> and
402 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
403 require C<search_literal>.
408 my ($self, $sql, @bind) = @_;
410 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
413 return $self->search(\[ $sql, map [ __DUMMY__ => $_ ], @bind ], ($attr || () ));
420 =item Arguments: @values | \%cols, \%attrs?
422 =item Return Value: $row_object | undef
426 Finds a row based on its primary key or unique constraint. For example, to find
427 a row by its primary key:
429 my $cd = $schema->resultset('CD')->find(5);
431 You can also find a row by a specific unique constraint using the C<key>
432 attribute. For example:
434 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
435 key => 'cd_artist_title'
438 Additionally, you can specify the columns explicitly by name:
440 my $cd = $schema->resultset('CD')->find(
442 artist => 'Massive Attack',
443 title => 'Mezzanine',
445 { key => 'cd_artist_title' }
448 If the C<key> is specified as C<primary>, it searches only on the primary key.
450 If no C<key> is specified, it searches on all unique constraints defined on the
451 source for which column data is provided, including the primary key.
453 If your table does not have a primary key, you B<must> provide a value for the
454 C<key> attribute matching one of the unique constraints on the source.
456 In addition to C<key>, L</find> recognizes and applies standard
457 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
459 Note: If your query does not return only one row, a warning is generated:
461 Query returned more than one row
463 See also L</find_or_create> and L</update_or_create>. For information on how to
464 declare unique constraints, see
465 L<DBIx::Class::ResultSource/add_unique_constraint>.
471 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
473 # Default to the primary key, but allow a specific key
474 my @cols = exists $attrs->{key}
475 ? $self->result_source->unique_constraint_columns($attrs->{key})
476 : $self->result_source->primary_columns;
477 $self->throw_exception(
478 "Can't find unless a primary key is defined or unique constraint is specified"
481 # Parse out a hashref from input
483 if (ref $_[0] eq 'HASH') {
484 $input_query = { %{$_[0]} };
486 elsif (@_ == @cols) {
488 @{$input_query}{@cols} = @_;
491 # Compatibility: Allow e.g. find(id => $value)
492 carp "Find by key => value deprecated; please use a hashref instead";
496 my (%related, $info);
498 KEY: foreach my $key (keys %$input_query) {
499 if (ref($input_query->{$key})
500 && ($info = $self->result_source->relationship_info($key))) {
501 my $val = delete $input_query->{$key};
502 next KEY if (ref($val) eq 'ARRAY'); # has_many for multi_create
503 my $rel_q = $self->result_source->_resolve_condition(
504 $info->{cond}, $val, $key
506 die "Can't handle OR join condition in find" if ref($rel_q) eq 'ARRAY';
507 @related{keys %$rel_q} = values %$rel_q;
510 if (my @keys = keys %related) {
511 @{$input_query}{@keys} = values %related;
515 # Build the final query: Default to the disjunction of the unique queries,
516 # but allow the input query in case the ResultSet defines the query or the
517 # user is abusing find
518 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
520 if (exists $attrs->{key}) {
521 my @unique_cols = $self->result_source->unique_constraint_columns($attrs->{key});
522 my $unique_query = $self->_build_unique_query($input_query, \@unique_cols);
523 $query = $self->_add_alias($unique_query, $alias);
525 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
526 # This means that we got here after a merger of relationship conditions
527 # in ::Relationship::Base::search_related (the row method), and furthermore
528 # the relationship is of the 'single' type. This means that the condition
529 # provided by the relationship (already attached to $self) is sufficient,
530 # as there can be only one row in the database that would satisfy the
534 my @unique_queries = $self->_unique_queries($input_query, $attrs);
535 $query = @unique_queries
536 ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
537 : $self->_add_alias($input_query, $alias);
540 # Run the query, passing the result_class since it should propagate for find
541 my $rs = $self->search ($query, {result_class => $self->result_class, %$attrs});
542 if (keys %{$rs->_resolved_attrs->{collapse}}) {
544 carp "Query returned more than one row" if $rs->next;
554 # Add the specified alias to the specified query hash. A copy is made so the
555 # original query is not modified.
558 my ($self, $query, $alias) = @_;
560 my %aliased = %$query;
561 foreach my $col (grep { ! m/\./ } keys %aliased) {
562 $aliased{"$alias.$col"} = delete $aliased{$col};
570 # Build a list of queries which satisfy unique constraints.
572 sub _unique_queries {
573 my ($self, $query, $attrs) = @_;
575 my @constraint_names = exists $attrs->{key}
577 : $self->result_source->unique_constraint_names;
579 my $where = $self->_collapse_cond($self->{attrs}{where} || {});
580 my $num_where = scalar keys %$where;
582 my (@unique_queries, %seen_column_combinations);
583 foreach my $name (@constraint_names) {
584 my @constraint_cols = $self->result_source->unique_constraint_columns($name);
586 my $constraint_sig = join "\x00", sort @constraint_cols;
587 next if $seen_column_combinations{$constraint_sig}++;
589 my $unique_query = $self->_build_unique_query($query, \@constraint_cols);
591 my $num_cols = scalar @constraint_cols;
592 my $num_query = scalar keys %$unique_query;
594 my $total = $num_query + $num_where;
595 if ($num_query && ($num_query == $num_cols || $total == $num_cols)) {
596 # The query is either unique on its own or is unique in combination with
597 # the existing where clause
598 push @unique_queries, $unique_query;
602 return @unique_queries;
605 # _build_unique_query
607 # Constrain the specified query hash based on the specified column names.
609 sub _build_unique_query {
610 my ($self, $query, $unique_cols) = @_;
613 map { $_ => $query->{$_} }
614 grep { exists $query->{$_} }
619 =head2 search_related
623 =item Arguments: $rel, $cond, \%attrs?
625 =item Return Value: $new_resultset
629 $new_rs = $cd_rs->search_related('artist', {
633 Searches the specified relationship, optionally specifying a condition and
634 attributes for matching records. See L</ATTRIBUTES> for more information.
639 return shift->related_resultset(shift)->search(@_);
642 =head2 search_related_rs
644 This method works exactly the same as search_related, except that
645 it guarantees a resultset, even in list context.
649 sub search_related_rs {
650 return shift->related_resultset(shift)->search_rs(@_);
657 =item Arguments: none
659 =item Return Value: $cursor
663 Returns a storage-driven cursor to the given resultset. See
664 L<DBIx::Class::Cursor> for more information.
671 my $attrs = $self->_resolved_attrs_copy;
673 return $self->{cursor}
674 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
675 $attrs->{where},$attrs);
682 =item Arguments: $cond?
684 =item Return Value: $row_object?
688 my $cd = $schema->resultset('CD')->single({ year => 2001 });
690 Inflates the first result without creating a cursor if the resultset has
691 any records in it; if not returns nothing. Used by L</find> as a lean version of
694 While this method can take an optional search condition (just like L</search>)
695 being a fast-code-path it does not recognize search attributes. If you need to
696 add extra joins or similar, call L</search> and then chain-call L</single> on the
697 L<DBIx::Class::ResultSet> returned.
703 As of 0.08100, this method enforces the assumption that the preceding
704 query returns only one row. If more than one row is returned, you will receive
707 Query returned more than one row
709 In this case, you should be using L</next> or L</find> instead, or if you really
710 know what you are doing, use the L</rows> attribute to explicitly limit the size
713 This method will also throw an exception if it is called on a resultset prefetching
714 has_many, as such a prefetch implies fetching multiple rows from the database in
715 order to assemble the resulting object.
722 my ($self, $where) = @_;
724 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
727 my $attrs = $self->_resolved_attrs_copy;
729 if (keys %{$attrs->{collapse}}) {
730 $self->throw_exception(
731 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
736 if (defined $attrs->{where}) {
739 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
740 $where, delete $attrs->{where} ]
743 $attrs->{where} = $where;
747 # XXX: Disabled since it doesn't infer uniqueness in all cases
748 # unless ($self->_is_unique_query($attrs->{where})) {
749 # carp "Query not guaranteed to return a single row"
750 # . "; please declare your unique constraints or use search instead";
753 my @data = $self->result_source->storage->select_single(
754 $attrs->{from}, $attrs->{select},
755 $attrs->{where}, $attrs
758 return (@data ? ($self->_construct_object(@data))[0] : undef);
764 # Try to determine if the specified query is guaranteed to be unique, based on
765 # the declared unique constraints.
767 sub _is_unique_query {
768 my ($self, $query) = @_;
770 my $collapsed = $self->_collapse_query($query);
771 my $alias = $self->{attrs}{alias};
773 foreach my $name ($self->result_source->unique_constraint_names) {
774 my @unique_cols = map {
776 } $self->result_source->unique_constraint_columns($name);
778 # Count the values for each unique column
779 my %seen = map { $_ => 0 } @unique_cols;
781 foreach my $key (keys %$collapsed) {
782 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
783 next unless exists $seen{$aliased}; # Additional constraints are okay
784 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
787 # If we get 0 or more than 1 value for a column, it's not necessarily unique
788 return 1 unless grep { $_ != 1 } values %seen;
796 # Recursively collapse the query, accumulating values for each column.
798 sub _collapse_query {
799 my ($self, $query, $collapsed) = @_;
803 if (ref $query eq 'ARRAY') {
804 foreach my $subquery (@$query) {
805 next unless ref $subquery; # -or
806 $collapsed = $self->_collapse_query($subquery, $collapsed);
809 elsif (ref $query eq 'HASH') {
810 if (keys %$query and (keys %$query)[0] eq '-and') {
811 foreach my $subquery (@{$query->{-and}}) {
812 $collapsed = $self->_collapse_query($subquery, $collapsed);
816 foreach my $col (keys %$query) {
817 my $value = $query->{$col};
818 $collapsed->{$col}{$value}++;
830 =item Arguments: $cond?
832 =item Return Value: $resultsetcolumn
836 my $max_length = $rs->get_column('length')->max;
838 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
843 my ($self, $column) = @_;
844 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
852 =item Arguments: $cond, \%attrs?
854 =item Return Value: $resultset (scalar context), @row_objs (list context)
858 # WHERE title LIKE '%blue%'
859 $cd_rs = $rs->search_like({ title => '%blue%'});
861 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
862 that this is simply a convenience method retained for ex Class::DBI users.
863 You most likely want to use L</search> with specific operators.
865 For more information, see L<DBIx::Class::Manual::Cookbook>.
867 This method is deprecated and will be removed in 0.09. Use L</search()>
868 instead. An example conversion is:
870 ->search_like({ foo => 'bar' });
874 ->search({ foo => { like => 'bar' } });
881 'search_like() is deprecated and will be removed in DBIC version 0.09.'
882 .' Instead use ->search({ x => { -like => "y%" } })'
883 .' (note the outer pair of {}s - they are important!)'
885 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
886 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
887 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
888 return $class->search($query, { %$attrs });
895 =item Arguments: $first, $last
897 =item Return Value: $resultset (scalar context), @row_objs (list context)
901 Returns a resultset or object list representing a subset of elements from the
902 resultset slice is called on. Indexes are from 0, i.e., to get the first
905 my ($one, $two, $three) = $rs->slice(0, 2);
910 my ($self, $min, $max) = @_;
911 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
912 $attrs->{offset} = $self->{attrs}{offset} || 0;
913 $attrs->{offset} += $min;
914 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
915 return $self->search(undef(), $attrs);
916 #my $slice = (ref $self)->new($self->result_source, $attrs);
917 #return (wantarray ? $slice->all : $slice);
924 =item Arguments: none
926 =item Return Value: $result?
930 Returns the next element in the resultset (C<undef> is there is none).
932 Can be used to efficiently iterate over records in the resultset:
934 my $rs = $schema->resultset('CD')->search;
935 while (my $cd = $rs->next) {
939 Note that you need to store the resultset object, and call C<next> on it.
940 Calling C<< resultset('Table')->next >> repeatedly will always return the
941 first record from the resultset.
947 if (my $cache = $self->get_cache) {
948 $self->{all_cache_position} ||= 0;
949 return $cache->[$self->{all_cache_position}++];
951 if ($self->{attrs}{cache}) {
952 $self->{all_cache_position} = 1;
953 return ($self->all)[0];
955 if ($self->{stashed_objects}) {
956 my $obj = shift(@{$self->{stashed_objects}});
957 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
961 exists $self->{stashed_row}
962 ? @{delete $self->{stashed_row}}
963 : $self->cursor->next
965 return undef unless (@row);
966 my ($row, @more) = $self->_construct_object(@row);
967 $self->{stashed_objects} = \@more if @more;
971 sub _construct_object {
972 my ($self, @row) = @_;
974 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row)
976 my @new = $self->result_class->inflate_result($self->result_source, @$info);
977 @new = $self->{_attrs}{record_filter}->(@new)
978 if exists $self->{_attrs}{record_filter};
982 sub _collapse_result {
983 my ($self, $as_proto, $row) = @_;
987 # 'foo' => [ undef, 'foo' ]
988 # 'foo.bar' => [ 'foo', 'bar' ]
989 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
991 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
993 my %collapse = %{$self->{_attrs}{collapse}||{}};
997 # if we're doing collapsing (has_many prefetch) we need to grab records
998 # until the PK changes, so fill @pri_index. if not, we leave it empty so
999 # we know we don't have to bother.
1001 # the reason for not using the collapse stuff directly is because if you
1002 # had for e.g. two artists in a row with no cds, the collapse info for
1003 # both would be NULL (undef) so you'd lose the second artist
1005 # store just the index so we can check the array positions from the row
1006 # without having to contruct the full hash
1008 if (keys %collapse) {
1009 my %pri = map { ($_ => 1) } $self->result_source->_pri_cols;
1010 foreach my $i (0 .. $#construct_as) {
1011 next if defined($construct_as[$i][0]); # only self table
1012 if (delete $pri{$construct_as[$i][1]}) {
1013 push(@pri_index, $i);
1015 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
1019 # no need to do an if, it'll be empty if @pri_index is empty anyway
1021 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
1025 do { # no need to check anything at the front, we always want the first row
1029 foreach my $this_as (@construct_as) {
1030 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
1033 push(@const_rows, \%const);
1035 } until ( # no pri_index => no collapse => drop straight out
1038 do { # get another row, stash it, drop out if different PK
1040 @copy = $self->cursor->next;
1041 $self->{stashed_row} = \@copy;
1043 # last thing in do block, counts as true if anything doesn't match
1045 # check xor defined first for NULL vs. NOT NULL then if one is
1046 # defined the other must be so check string equality
1049 (defined $pri_vals{$_} ^ defined $copy[$_])
1050 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
1055 my $alias = $self->{attrs}{alias};
1062 foreach my $const (@const_rows) {
1063 scalar @const_keys or do {
1064 @const_keys = sort { length($a) <=> length($b) } keys %$const;
1066 foreach my $key (@const_keys) {
1069 my @parts = split(/\./, $key);
1071 my $data = $const->{$key};
1072 foreach my $p (@parts) {
1073 $target = $target->[1]->{$p} ||= [];
1075 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
1076 # collapsing at this point and on final part
1077 my $pos = $collapse_pos{$cur};
1078 CK: foreach my $ck (@ckey) {
1079 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
1080 $collapse_pos{$cur} = $data;
1081 delete @collapse_pos{ # clear all positioning for sub-entries
1082 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
1089 if (exists $collapse{$cur}) {
1090 $target = $target->[-1];
1093 $target->[0] = $data;
1095 $info->[0] = $const->{$key};
1103 =head2 result_source
1107 =item Arguments: $result_source?
1109 =item Return Value: $result_source
1113 An accessor for the primary ResultSource object from which this ResultSet
1120 =item Arguments: $result_class?
1122 =item Return Value: $result_class
1126 An accessor for the class to use when creating row objects. Defaults to
1127 C<< result_source->result_class >> - which in most cases is the name of the
1128 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1130 Note that changing the result_class will also remove any components
1131 that were originally loaded in the source class via
1132 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1133 in the original source class will not run.
1138 my ($self, $result_class) = @_;
1139 if ($result_class) {
1140 unless (ref $result_class) { # don't fire this for an object
1141 $self->ensure_class_loaded($result_class);
1143 $self->_result_class($result_class);
1144 # THIS LINE WOULD BE A BUG - this accessor specifically exists to
1145 # permit the user to set result class on one result set only; it only
1146 # chains if provided to search()
1147 #$self->{attrs}{result_class} = $result_class if ref $self;
1149 $self->_result_class;
1156 =item Arguments: $cond, \%attrs??
1158 =item Return Value: $count
1162 Performs an SQL C<COUNT> with the same query as the resultset was built
1163 with to find the number of elements. Passing arguments is equivalent to
1164 C<< $rs->search ($cond, \%attrs)->count >>
1170 return $self->search(@_)->count if @_ and defined $_[0];
1171 return scalar @{ $self->get_cache } if $self->get_cache;
1173 my $attrs = $self->_resolved_attrs_copy;
1175 # this is a little optimization - it is faster to do the limit
1176 # adjustments in software, instead of a subquery
1177 my $rows = delete $attrs->{rows};
1178 my $offset = delete $attrs->{offset};
1181 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1182 $crs = $self->_count_subq_rs ($attrs);
1185 $crs = $self->_count_rs ($attrs);
1187 my $count = $crs->next;
1189 $count -= $offset if $offset;
1190 $count = $rows if $rows and $rows < $count;
1191 $count = 0 if ($count < 0);
1200 =item Arguments: $cond, \%attrs??
1202 =item Return Value: $count_rs
1206 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1207 This can be very handy for subqueries:
1209 ->search( { amount => $some_rs->count_rs->as_query } )
1211 As with regular resultsets the SQL query will be executed only after
1212 the resultset is accessed via L</next> or L</all>. That would return
1213 the same single value obtainable via L</count>.
1219 return $self->search(@_)->count_rs if @_;
1221 # this may look like a lack of abstraction (count() does about the same)
1222 # but in fact an _rs *must* use a subquery for the limits, as the
1223 # software based limiting can not be ported if this $rs is to be used
1224 # in a subquery itself (i.e. ->as_query)
1225 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1226 return $self->_count_subq_rs;
1229 return $self->_count_rs;
1234 # returns a ResultSetColumn object tied to the count query
1237 my ($self, $attrs) = @_;
1239 my $rsrc = $self->result_source;
1240 $attrs ||= $self->_resolved_attrs;
1242 my $tmp_attrs = { %$attrs };
1243 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1244 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1246 # overwrite the selector (supplied by the storage)
1247 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $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 $sub_attrs = { %$attrs };
1265 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1266 delete @{$sub_attrs}{qw/collapse select _prefetch_select as order_by for/};
1268 # if we multi-prefetch we group_by primary keys only as this is what we would
1269 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1270 if ( keys %{$attrs->{collapse}} ) {
1271 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } ($rsrc->_pri_cols) ]
1274 # Calculate subquery selector
1275 if (my $g = $sub_attrs->{group_by}) {
1277 # necessary as the group_by may refer to aliased functions
1279 for my $sel (@{$attrs->{select}}) {
1280 $sel_index->{$sel->{-as}} = $sel
1281 if (ref $sel eq 'HASH' and $sel->{-as});
1284 for my $g_part (@$g) {
1285 push @{$sub_attrs->{select}}, $sel_index->{$g_part} || $g_part;
1289 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1290 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1293 return $rsrc->resultset_class
1294 ->new ($rsrc, $sub_attrs)
1296 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1297 ->get_column ('count');
1304 =head2 count_literal
1308 =item Arguments: $sql_fragment, @bind_values
1310 =item Return Value: $count
1314 Counts the results in a literal query. Equivalent to calling L</search_literal>
1315 with the passed arguments, then L</count>.
1319 sub count_literal { shift->search_literal(@_)->count; }
1325 =item Arguments: none
1327 =item Return Value: @objects
1331 Returns all elements in the resultset. Called implicitly if the resultset
1332 is returned in list context.
1339 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1342 return @{ $self->get_cache } if $self->get_cache;
1346 if (keys %{$self->_resolved_attrs->{collapse}}) {
1347 # Using $self->cursor->all is really just an optimisation.
1348 # If we're collapsing has_many prefetches it probably makes
1349 # very little difference, and this is cleaner than hacking
1350 # _construct_object to survive the approach
1351 $self->cursor->reset;
1352 my @row = $self->cursor->next;
1354 push(@obj, $self->_construct_object(@row));
1355 @row = (exists $self->{stashed_row}
1356 ? @{delete $self->{stashed_row}}
1357 : $self->cursor->next);
1360 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1363 $self->set_cache(\@obj) if $self->{attrs}{cache};
1372 =item Arguments: none
1374 =item Return Value: $self
1378 Resets the resultset's cursor, so you can iterate through the elements again.
1379 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1386 delete $self->{_attrs} if exists $self->{_attrs};
1387 $self->{all_cache_position} = 0;
1388 $self->cursor->reset;
1396 =item Arguments: none
1398 =item Return Value: $object?
1402 Resets the resultset and returns an object for the first result (if the
1403 resultset returns anything).
1408 return $_[0]->reset->next;
1414 # Determines whether and what type of subquery is required for the $rs operation.
1415 # If grouping is necessary either supplies its own, or verifies the current one
1416 # After all is done delegates to the proper storage method.
1418 sub _rs_update_delete {
1419 my ($self, $op, $values) = @_;
1421 my $rsrc = $self->result_source;
1423 # if a condition exists we need to strip all table qualifiers
1424 # if this is not possible we'll force a subquery below
1425 my $cond = $rsrc->schema->storage->_strip_cond_qualifiers ($self->{cond});
1427 my $needs_group_by_subq = $self->_has_resolved_attr (qw/collapse group_by -join/);
1428 my $needs_subq = $needs_group_by_subq || (not defined $cond) || $self->_has_resolved_attr(qw/rows offset/);
1430 if ($needs_group_by_subq or $needs_subq) {
1432 # make a new $rs selecting only the PKs (that's all we really need)
1433 my $attrs = $self->_resolved_attrs_copy;
1436 delete $attrs->{$_} for qw/collapse _collapse_order_by select _prefetch_select as/;
1437 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->_pri_cols) ];
1439 if ($needs_group_by_subq) {
1440 # make sure no group_by was supplied, or if there is one - make sure it matches
1441 # the columns compiled above perfectly. Anything else can not be sanely executed
1442 # on most databases so croak right then and there
1444 if (my $g = $attrs->{group_by}) {
1445 my @current_group_by = map
1446 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1451 join ("\x00", sort @current_group_by)
1453 join ("\x00", sort @{$attrs->{columns}} )
1455 $self->throw_exception (
1456 "You have just attempted a $op operation on a resultset which does group_by"
1457 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1458 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1459 . ' kind of queries. Please retry the operation with a modified group_by or'
1460 . ' without using one at all.'
1465 $attrs->{group_by} = $attrs->{columns};
1469 my $subrs = (ref $self)->new($rsrc, $attrs);
1470 return $self->result_source->storage->_subq_update_delete($subrs, $op, $values);
1473 return $rsrc->storage->$op(
1475 $op eq 'update' ? $values : (),
1485 =item Arguments: \%values
1487 =item Return Value: $storage_rv
1491 Sets the specified columns in the resultset to the supplied values in a
1492 single query. Return value will be true if the update succeeded or false
1493 if no records were updated; exact type of success value is storage-dependent.
1498 my ($self, $values) = @_;
1499 $self->throw_exception('Values for update must be a hash')
1500 unless ref $values eq 'HASH';
1502 return $self->_rs_update_delete ('update', $values);
1509 =item Arguments: \%values
1511 =item Return Value: 1
1515 Fetches all objects and updates them one at a time. Note that C<update_all>
1516 will run DBIC cascade triggers, while L</update> will not.
1521 my ($self, $values) = @_;
1522 $self->throw_exception('Values for update_all must be a hash')
1523 unless ref $values eq 'HASH';
1525 my $guard = $self->result_source->schema->txn_scope_guard;
1526 $_->update($values) for $self->all;
1535 =item Arguments: none
1537 =item Return Value: $storage_rv
1541 Deletes the contents of the resultset from its result source. Note that this
1542 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1543 to run. See also L<DBIx::Class::Row/delete>.
1545 Return value will be the number of rows deleted; exact type of return value
1546 is storage-dependent.
1552 $self->throw_exception('delete does not accept any arguments')
1555 return $self->_rs_update_delete ('delete');
1562 =item Arguments: none
1564 =item Return Value: 1
1568 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1569 will run DBIC cascade triggers, while L</delete> will not.
1575 $self->throw_exception('delete_all does not accept any arguments')
1578 my $guard = $self->result_source->schema->txn_scope_guard;
1579 $_->delete for $self->all;
1588 =item Arguments: \@data;
1592 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1593 For the arrayref of hashrefs style each hashref should be a structure suitable
1594 forsubmitting to a $resultset->create(...) method.
1596 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1597 to insert the data, as this is a faster method.
1599 Otherwise, each set of data is inserted into the database using
1600 L<DBIx::Class::ResultSet/create>, and the resulting objects are
1601 accumulated into an array. The array itself, or an array reference
1602 is returned depending on scalar or list context.
1604 Example: Assuming an Artist Class that has many CDs Classes relating:
1606 my $Artist_rs = $schema->resultset("Artist");
1608 ## Void Context Example
1609 $Artist_rs->populate([
1610 { artistid => 4, name => 'Manufactured Crap', cds => [
1611 { title => 'My First CD', year => 2006 },
1612 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1615 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1616 { title => 'My parents sold me to a record company', year => 2005 },
1617 { title => 'Why Am I So Ugly?', year => 2006 },
1618 { title => 'I Got Surgery and am now Popular', year => 2007 }
1623 ## Array Context Example
1624 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1625 { name => "Artist One"},
1626 { name => "Artist Two"},
1627 { name => "Artist Three", cds=> [
1628 { title => "First CD", year => 2007},
1629 { title => "Second CD", year => 2008},
1633 print $ArtistOne->name; ## response is 'Artist One'
1634 print $ArtistThree->cds->count ## reponse is '2'
1636 For the arrayref of arrayrefs style, the first element should be a list of the
1637 fieldsnames to which the remaining elements are rows being inserted. For
1640 $Arstist_rs->populate([
1641 [qw/artistid name/],
1642 [100, 'A Formally Unknown Singer'],
1643 [101, 'A singer that jumped the shark two albums ago'],
1644 [102, 'An actually cool singer'],
1647 Please note an important effect on your data when choosing between void and
1648 wantarray context. Since void context goes straight to C<insert_bulk> in
1649 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
1650 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
1651 create primary keys for you, you will find that your PKs are empty. In this
1652 case you will have to use the wantarray context in order to create those
1660 # cruft placed in standalone method
1661 my $data = $self->_normalize_populate_args(@_);
1663 if(defined wantarray) {
1665 foreach my $item (@$data) {
1666 push(@created, $self->create($item));
1668 return wantarray ? @created : \@created;
1670 my $first = $data->[0];
1672 # if a column is a registered relationship, and is a non-blessed hash/array, consider
1673 # it relationship data
1674 my (@rels, @columns);
1675 for (keys %$first) {
1676 my $ref = ref $first->{$_};
1677 $self->result_source->has_relationship($_) && ($ref eq 'ARRAY' or $ref eq 'HASH')
1683 my @pks = $self->result_source->primary_columns;
1685 ## do the belongs_to relationships
1686 foreach my $index (0..$#$data) {
1688 # delegate to create() for any dataset without primary keys with specified relationships
1689 if (grep { !defined $data->[$index]->{$_} } @pks ) {
1691 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
1692 my @ret = $self->populate($data);
1698 foreach my $rel (@rels) {
1699 next unless ref $data->[$index]->{$rel} eq "HASH";
1700 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1701 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1702 my $related = $result->result_source->_resolve_condition(
1703 $result->result_source->relationship_info($reverse)->{cond},
1708 delete $data->[$index]->{$rel};
1709 $data->[$index] = {%{$data->[$index]}, %$related};
1711 push @columns, keys %$related if $index == 0;
1715 ## inherit the data locked in the conditions of the resultset
1716 my ($rs_data) = $self->_merge_cond_with_data({});
1717 delete @{$rs_data}{@columns};
1718 my @inherit_cols = keys %$rs_data;
1719 my @inherit_data = values %$rs_data;
1721 ## do bulk insert on current row
1722 $self->result_source->storage->insert_bulk(
1723 $self->result_source,
1724 [@columns, @inherit_cols],
1725 [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
1728 ## do the has_many relationships
1729 foreach my $item (@$data) {
1731 foreach my $rel (@rels) {
1732 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1734 my $parent = $self->find({map { $_ => $item->{$_} } @pks})
1735 || $self->throw_exception('Cannot find the relating object.');
1737 my $child = $parent->$rel;
1739 my $related = $child->result_source->_resolve_condition(
1740 $parent->result_source->relationship_info($rel)->{cond},
1745 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1746 my @populate = map { {%$_, %$related} } @rows_to_add;
1748 $child->populate( \@populate );
1755 # populate() argumnets went over several incarnations
1756 # What we ultimately support is AoH
1757 sub _normalize_populate_args {
1758 my ($self, $arg) = @_;
1760 if (ref $arg eq 'ARRAY') {
1761 if (ref $arg->[0] eq 'HASH') {
1764 elsif (ref $arg->[0] eq 'ARRAY') {
1766 my @colnames = @{$arg->[0]};
1767 foreach my $values (@{$arg}[1 .. $#$arg]) {
1768 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
1774 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
1781 =item Arguments: none
1783 =item Return Value: $pager
1787 Return Value a L<Data::Page> object for the current resultset. Only makes
1788 sense for queries with a C<page> attribute.
1790 To get the full count of entries for a paged resultset, call
1791 C<total_entries> on the L<Data::Page> object.
1798 return $self->{pager} if $self->{pager};
1800 my $attrs = $self->{attrs};
1801 $self->throw_exception("Can't create pager for non-paged rs")
1802 unless $self->{attrs}{page};
1803 $attrs->{rows} ||= 10;
1805 # throw away the paging flags and re-run the count (possibly
1806 # with a subselect) to get the real total count
1807 my $count_attrs = { %$attrs };
1808 delete $count_attrs->{$_} for qw/rows offset page pager/;
1809 my $total_count = (ref $self)->new($self->result_source, $count_attrs)->count;
1811 return $self->{pager} = Data::Page->new(
1814 $self->{attrs}{page}
1822 =item Arguments: $page_number
1824 =item Return Value: $rs
1828 Returns a resultset for the $page_number page of the resultset on which page
1829 is called, where each page contains a number of rows equal to the 'rows'
1830 attribute set on the resultset (10 by default).
1835 my ($self, $page) = @_;
1836 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1843 =item Arguments: \%vals
1845 =item Return Value: $rowobject
1849 Creates a new row object in the resultset's result class and returns
1850 it. The row is not inserted into the database at this point, call
1851 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
1852 will tell you whether the row object has been inserted or not.
1854 Passes the hashref of input on to L<DBIx::Class::Row/new>.
1859 my ($self, $values) = @_;
1860 $self->throw_exception( "new_result needs a hash" )
1861 unless (ref $values eq 'HASH');
1863 my ($merged_cond, $cols_from_relations) = $self->_merge_cond_with_data($values);
1867 @$cols_from_relations
1868 ? (-cols_from_relations => $cols_from_relations)
1870 -source_handle => $self->_source_handle,
1871 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
1874 return $self->result_class->new(\%new);
1877 # _merge_cond_with_data
1879 # Takes a simple hash of K/V data and returns its copy merged with the
1880 # condition already present on the resultset. Additionally returns an
1881 # arrayref of value/condition names, which were inferred from related
1882 # objects (this is needed for in-memory related objects)
1883 sub _merge_cond_with_data {
1884 my ($self, $data) = @_;
1886 my (%new_data, @cols_from_relations);
1888 my $alias = $self->{attrs}{alias};
1890 if (! defined $self->{cond}) {
1891 # just massage $data below
1893 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
1894 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
1895 @cols_from_relations = keys %new_data;
1897 elsif (ref $self->{cond} ne 'HASH') {
1898 $self->throw_exception(
1899 "Can't abstract implicit construct, resultset condition not a hash"
1903 # precendence must be given to passed values over values inherited from
1904 # the cond, so the order here is important.
1905 my $collapsed_cond = $self->_collapse_cond($self->{cond});
1906 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
1908 while ( my($col, $value) = each %implied ) {
1909 if (ref($value) eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '=') {
1910 $new_data{$col} = $value->{'='};
1913 $new_data{$col} = $value if $self->_is_deterministic_value($value);
1919 %{ $self->_remove_alias($data, $alias) },
1922 return (\%new_data, \@cols_from_relations);
1925 # _is_deterministic_value
1927 # Make an effor to strip non-deterministic values from the condition,
1928 # to make sure new_result chokes less
1930 sub _is_deterministic_value {
1933 my $ref_type = ref $value;
1934 return 1 if $ref_type eq '' || $ref_type eq 'SCALAR';
1935 return 1 if blessed $value;
1939 # _has_resolved_attr
1941 # determines if the resultset defines at least one
1942 # of the attributes supplied
1944 # used to determine if a subquery is neccessary
1946 # supports some virtual attributes:
1948 # This will scan for any joins being present on the resultset.
1949 # It is not a mere key-search but a deep inspection of {from}
1952 sub _has_resolved_attr {
1953 my ($self, @attr_names) = @_;
1955 my $attrs = $self->_resolved_attrs;
1959 for my $n (@attr_names) {
1960 if (grep { $n eq $_ } (qw/-join/) ) {
1961 $extra_checks{$n}++;
1965 my $attr = $attrs->{$n};
1967 next if not defined $attr;
1969 if (ref $attr eq 'HASH') {
1970 return 1 if keys %$attr;
1972 elsif (ref $attr eq 'ARRAY') {
1980 # a resolved join is expressed as a multi-level from
1982 $extra_checks{-join}
1984 ref $attrs->{from} eq 'ARRAY'
1986 @{$attrs->{from}} > 1
1994 # Recursively collapse the condition.
1996 sub _collapse_cond {
1997 my ($self, $cond, $collapsed) = @_;
2001 if (ref $cond eq 'ARRAY') {
2002 foreach my $subcond (@$cond) {
2003 next unless ref $subcond; # -or
2004 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2007 elsif (ref $cond eq 'HASH') {
2008 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2009 foreach my $subcond (@{$cond->{-and}}) {
2010 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2014 foreach my $col (keys %$cond) {
2015 my $value = $cond->{$col};
2016 $collapsed->{$col} = $value;
2026 # Remove the specified alias from the specified query hash. A copy is made so
2027 # the original query is not modified.
2030 my ($self, $query, $alias) = @_;
2032 my %orig = %{ $query || {} };
2035 foreach my $key (keys %orig) {
2037 $unaliased{$key} = $orig{$key};
2040 $unaliased{$1} = $orig{$key}
2041 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2051 =item Arguments: none
2053 =item Return Value: \[ $sql, @bind ]
2057 Returns the SQL query and bind vars associated with the invocant.
2059 This is generally used as the RHS for a subquery.
2066 my $attrs = $self->_resolved_attrs_copy;
2071 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2072 # $sql also has no wrapping parenthesis in list ctx
2074 my $sqlbind = $self->result_source->storage
2075 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2084 =item Arguments: \%vals, \%attrs?
2086 =item Return Value: $rowobject
2090 my $artist = $schema->resultset('Artist')->find_or_new(
2091 { artist => 'fred' }, { key => 'artists' });
2093 $cd->cd_to_producer->find_or_new({ producer => $producer },
2094 { key => 'primary });
2096 Find an existing record from this resultset, based on its primary
2097 key, or a unique constraint. If none exists, instantiate a new result
2098 object and return it. The object will not be saved into your storage
2099 until you call L<DBIx::Class::Row/insert> on it.
2101 You most likely want this method when looking for existing rows using
2102 a unique constraint that is not the primary key, or looking for
2105 If you want objects to be saved immediately, use L</find_or_create>
2108 B<Note>: Take care when using C<find_or_new> with a table having
2109 columns with default values that you intend to be automatically
2110 supplied by the database (e.g. an auto_increment primary key column).
2111 In normal usage, the value of such columns should NOT be included at
2112 all in the call to C<find_or_new>, even when set to C<undef>.
2118 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2119 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2120 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2123 return $self->new_result($hash);
2130 =item Arguments: \%vals
2132 =item Return Value: a L<DBIx::Class::Row> $object
2136 Attempt to create a single new row or a row with multiple related rows
2137 in the table represented by the resultset (and related tables). This
2138 will not check for duplicate rows before inserting, use
2139 L</find_or_create> to do that.
2141 To create one row for this resultset, pass a hashref of key/value
2142 pairs representing the columns of the table and the values you wish to
2143 store. If the appropriate relationships are set up, foreign key fields
2144 can also be passed an object representing the foreign row, and the
2145 value will be set to its primary key.
2147 To create related objects, pass a hashref of related-object column values
2148 B<keyed on the relationship name>. If the relationship is of type C<multi>
2149 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2150 The process will correctly identify columns holding foreign keys, and will
2151 transparently populate them from the keys of the corresponding relation.
2152 This can be applied recursively, and will work correctly for a structure
2153 with an arbitrary depth and width, as long as the relationships actually
2154 exists and the correct column data has been supplied.
2157 Instead of hashrefs of plain related data (key/value pairs), you may
2158 also pass new or inserted objects. New objects (not inserted yet, see
2159 L</new>), will be inserted into their appropriate tables.
2161 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2163 Example of creating a new row.
2165 $person_rs->create({
2166 name=>"Some Person",
2167 email=>"somebody@someplace.com"
2170 Example of creating a new row and also creating rows in a related C<has_many>
2171 or C<has_one> resultset. Note Arrayref.
2174 { artistid => 4, name => 'Manufactured Crap', cds => [
2175 { title => 'My First CD', year => 2006 },
2176 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2181 Example of creating a new row and also creating a row in a related
2182 C<belongs_to> resultset. Note Hashref.
2185 title=>"Music for Silly Walks",
2188 name=>"Silly Musician",
2196 When subclassing ResultSet never attempt to override this method. Since
2197 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2198 lot of the internals simply never call it, so your override will be
2199 bypassed more often than not. Override either L<new|DBIx::Class::Row/new>
2200 or L<insert|DBIx::Class::Row/insert> depending on how early in the
2201 L</create> process you need to intervene.
2208 my ($self, $attrs) = @_;
2209 $self->throw_exception( "create needs a hashref" )
2210 unless ref $attrs eq 'HASH';
2211 return $self->new_result($attrs)->insert;
2214 =head2 find_or_create
2218 =item Arguments: \%vals, \%attrs?
2220 =item Return Value: $rowobject
2224 $cd->cd_to_producer->find_or_create({ producer => $producer },
2225 { key => 'primary' });
2227 Tries to find a record based on its primary key or unique constraints; if none
2228 is found, creates one and returns that instead.
2230 my $cd = $schema->resultset('CD')->find_or_create({
2232 artist => 'Massive Attack',
2233 title => 'Mezzanine',
2237 Also takes an optional C<key> attribute, to search by a specific key or unique
2238 constraint. For example:
2240 my $cd = $schema->resultset('CD')->find_or_create(
2242 artist => 'Massive Attack',
2243 title => 'Mezzanine',
2245 { key => 'cd_artist_title' }
2248 B<Note>: Because find_or_create() reads from the database and then
2249 possibly inserts based on the result, this method is subject to a race
2250 condition. Another process could create a record in the table after
2251 the find has completed and before the create has started. To avoid
2252 this problem, use find_or_create() inside a transaction.
2254 B<Note>: Take care when using C<find_or_create> with a table having
2255 columns with default values that you intend to be automatically
2256 supplied by the database (e.g. an auto_increment primary key column).
2257 In normal usage, the value of such columns should NOT be included at
2258 all in the call to C<find_or_create>, even when set to C<undef>.
2260 See also L</find> and L</update_or_create>. For information on how to declare
2261 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2265 sub find_or_create {
2267 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2268 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2269 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2272 return $self->create($hash);
2275 =head2 update_or_create
2279 =item Arguments: \%col_values, { key => $unique_constraint }?
2281 =item Return Value: $rowobject
2285 $resultset->update_or_create({ col => $val, ... });
2287 First, searches for an existing row matching one of the unique constraints
2288 (including the primary key) on the source of this resultset. If a row is
2289 found, updates it with the other given column values. Otherwise, creates a new
2292 Takes an optional C<key> attribute to search on a specific unique constraint.
2295 # In your application
2296 my $cd = $schema->resultset('CD')->update_or_create(
2298 artist => 'Massive Attack',
2299 title => 'Mezzanine',
2302 { key => 'cd_artist_title' }
2305 $cd->cd_to_producer->update_or_create({
2306 producer => $producer,
2313 If no C<key> is specified, it searches on all unique constraints defined on the
2314 source, including the primary key.
2316 If the C<key> is specified as C<primary>, it searches only on the primary key.
2318 See also L</find> and L</find_or_create>. For information on how to declare
2319 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2321 B<Note>: Take care when using C<update_or_create> with a table having
2322 columns with default values that you intend to be automatically
2323 supplied by the database (e.g. an auto_increment primary key column).
2324 In normal usage, the value of such columns should NOT be included at
2325 all in the call to C<update_or_create>, even when set to C<undef>.
2329 sub update_or_create {
2331 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2332 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2334 my $row = $self->find($cond, $attrs);
2336 $row->update($cond);
2340 return $self->create($cond);
2343 =head2 update_or_new
2347 =item Arguments: \%col_values, { key => $unique_constraint }?
2349 =item Return Value: $rowobject
2353 $resultset->update_or_new({ col => $val, ... });
2355 First, searches for an existing row matching one of the unique constraints
2356 (including the primary key) on the source of this resultset. If a row is
2357 found, updates it with the other given column values. Otherwise, instantiate
2358 a new result object and return it. The object will not be saved into your storage
2359 until you call L<DBIx::Class::Row/insert> on it.
2361 Takes an optional C<key> attribute to search on a specific unique constraint.
2364 # In your application
2365 my $cd = $schema->resultset('CD')->update_or_new(
2367 artist => 'Massive Attack',
2368 title => 'Mezzanine',
2371 { key => 'cd_artist_title' }
2374 if ($cd->in_storage) {
2375 # the cd was updated
2378 # the cd is not yet in the database, let's insert it
2382 B<Note>: Take care when using C<update_or_new> with a table having
2383 columns with default values that you intend to be automatically
2384 supplied by the database (e.g. an auto_increment primary key column).
2385 In normal usage, the value of such columns should NOT be included at
2386 all in the call to C<update_or_new>, even when set to C<undef>.
2388 See also L</find>, L</find_or_create> and L</find_or_new>.
2394 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2395 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2397 my $row = $self->find( $cond, $attrs );
2398 if ( defined $row ) {
2399 $row->update($cond);
2403 return $self->new_result($cond);
2410 =item Arguments: none
2412 =item Return Value: \@cache_objects?
2416 Gets the contents of the cache for the resultset, if the cache is set.
2418 The cache is populated either by using the L</prefetch> attribute to
2419 L</search> or by calling L</set_cache>.
2431 =item Arguments: \@cache_objects
2433 =item Return Value: \@cache_objects
2437 Sets the contents of the cache for the resultset. Expects an arrayref
2438 of objects of the same class as those produced by the resultset. Note that
2439 if the cache is set the resultset will return the cached objects rather
2440 than re-querying the database even if the cache attr is not set.
2442 The contents of the cache can also be populated by using the
2443 L</prefetch> attribute to L</search>.
2448 my ( $self, $data ) = @_;
2449 $self->throw_exception("set_cache requires an arrayref")
2450 if defined($data) && (ref $data ne 'ARRAY');
2451 $self->{all_cache} = $data;
2458 =item Arguments: none
2460 =item Return Value: []
2464 Clears the cache for the resultset.
2469 shift->set_cache(undef);
2476 =item Arguments: none
2478 =item Return Value: true, if the resultset has been paginated
2486 return !!$self->{attrs}{page};
2493 =item Arguments: none
2495 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2503 return scalar $self->result_source->storage->_parse_order_by($self->{attrs}{order_by});
2506 =head2 related_resultset
2510 =item Arguments: $relationship_name
2512 =item Return Value: $resultset
2516 Returns a related resultset for the supplied relationship name.
2518 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2522 sub related_resultset {
2523 my ($self, $rel) = @_;
2525 $self->{related_resultsets} ||= {};
2526 return $self->{related_resultsets}{$rel} ||= do {
2527 my $rsrc = $self->result_source;
2528 my $rel_info = $rsrc->relationship_info($rel);
2530 $self->throw_exception(
2531 "search_related: result source '" . $rsrc->source_name .
2532 "' has no such relationship $rel")
2535 my $attrs = $self->_chain_relationship($rel);
2537 my $join_count = $attrs->{seen_join}{$rel};
2539 my $alias = $self->result_source->storage
2540 ->relname_to_table_alias($rel, $join_count);
2542 # since this is search_related, and we already slid the select window inwards
2543 # (the select/as attrs were deleted in the beginning), we need to flip all
2544 # left joins to inner, so we get the expected results
2545 # read the comment on top of the actual function to see what this does
2546 $attrs->{from} = $rsrc->schema->storage->_straight_join_to_node ($attrs->{from}, $alias);
2549 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2550 delete @{$attrs}{qw(result_class alias)};
2554 if (my $cache = $self->get_cache) {
2555 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2556 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
2561 my $rel_source = $rsrc->related_source($rel);
2565 # The reason we do this now instead of passing the alias to the
2566 # search_rs below is that if you wrap/overload resultset on the
2567 # source you need to know what alias it's -going- to have for things
2568 # to work sanely (e.g. RestrictWithObject wants to be able to add
2569 # extra query restrictions, and these may need to be $alias.)
2571 my $rel_attrs = $rel_source->resultset_attributes;
2572 local $rel_attrs->{alias} = $alias;
2574 $rel_source->resultset
2578 where => $attrs->{where},
2581 $new->set_cache($new_cache) if $new_cache;
2586 =head2 current_source_alias
2590 =item Arguments: none
2592 =item Return Value: $source_alias
2596 Returns the current table alias for the result source this resultset is built
2597 on, that will be used in the SQL query. Usually it is C<me>.
2599 Currently the source alias that refers to the result set returned by a
2600 L</search>/L</find> family method depends on how you got to the resultset: it's
2601 C<me> by default, but eg. L</search_related> aliases it to the related result
2602 source name (and keeps C<me> referring to the original result set). The long
2603 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
2604 (and make this method unnecessary).
2606 Thus it's currently necessary to use this method in predefined queries (see
2607 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
2608 source alias of the current result set:
2610 # in a result set class
2612 my ($self, $user) = @_;
2614 my $me = $self->current_source_alias;
2616 return $self->search(
2617 "$me.modified" => $user->id,
2623 sub current_source_alias {
2626 return ($self->{attrs} || {})->{alias} || 'me';
2629 =head2 as_subselect_rs
2633 =item Arguments: none
2635 =item Return Value: $resultset
2639 Act as a barrier to SQL symbols. The resultset provided will be made into a
2640 "virtual view" by including it as a subquery within the from clause. From this
2641 point on, any joined tables are inaccessible to ->search on the resultset (as if
2642 it were simply where-filtered without joins). For example:
2644 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
2646 # 'x' now pollutes the query namespace
2648 # So the following works as expected
2649 my $ok_rs = $rs->search({'x.other' => 1});
2651 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
2652 # def) we look for one row with contradictory terms and join in another table
2653 # (aliased 'x_2') which we never use
2654 my $broken_rs = $rs->search({'x.name' => 'def'});
2656 my $rs2 = $rs->as_subselect_rs;
2658 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
2659 my $not_joined_rs = $rs2->search({'x.other' => 1});
2661 # works as expected: finds a 'table' row related to two x rows (abc and def)
2662 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
2664 Another example of when one might use this would be to select a subset of
2665 columns in a group by clause:
2667 my $rs = $schema->resultset('Bar')->search(undef, {
2668 group_by => [qw{ id foo_id baz_id }],
2669 })->as_subselect_rs->search(undef, {
2670 columns => [qw{ id foo_id }]
2673 In the above example normally columns would have to be equal to the group by,
2674 but because we isolated the group by into a subselect the above works.
2678 sub as_subselect_rs {
2681 my $attrs = $self->_resolved_attrs;
2683 my $fresh_rs = (ref $self)->new (
2684 $self->result_source
2687 # these pieces will be locked in the subquery
2688 delete $fresh_rs->{cond};
2689 delete @{$fresh_rs->{attrs}}{qw/where bind/};
2691 return $fresh_rs->search( {}, {
2693 $attrs->{alias} => $self->as_query,
2694 -alias => $attrs->{alias},
2695 -source_handle => $self->result_source->handle,
2697 alias => $attrs->{alias},
2701 # This code is called by search_related, and makes sure there
2702 # is clear separation between the joins before, during, and
2703 # after the relationship. This information is needed later
2704 # in order to properly resolve prefetch aliases (any alias
2705 # with a relation_chain_depth less than the depth of the
2706 # current prefetch is not considered)
2708 # The increments happen twice per join. An even number means a
2709 # relationship specified via a search_related, whereas an odd
2710 # number indicates a join/prefetch added via attributes
2712 # Also this code will wrap the current resultset (the one we
2713 # chain to) in a subselect IFF it contains limiting attributes
2714 sub _chain_relationship {
2715 my ($self, $rel) = @_;
2716 my $source = $self->result_source;
2717 my $attrs = { %{$self->{attrs}||{}} };
2719 # we need to take the prefetch the attrs into account before we
2720 # ->_resolve_join as otherwise they get lost - captainL
2721 my $join = $self->_merge_attr( $attrs->{join}, $attrs->{prefetch} );
2723 delete @{$attrs}{qw/join prefetch collapse group_by distinct select as columns +select +as +columns/};
2725 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
2728 my @force_subq_attrs = qw/offset rows group_by having/;
2731 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
2733 $self->_has_resolved_attr (@force_subq_attrs)
2735 # Nuke the prefetch (if any) before the new $rs attrs
2736 # are resolved (prefetch is useless - we are wrapping
2737 # a subquery anyway).
2738 my $rs_copy = $self->search;
2739 $rs_copy->{attrs}{join} = $self->_merge_attr (
2740 $rs_copy->{attrs}{join},
2741 delete $rs_copy->{attrs}{prefetch},
2745 -source_handle => $source->handle,
2746 -alias => $attrs->{alias},
2747 $attrs->{alias} => $rs_copy->as_query,
2749 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
2750 $seen->{-relation_chain_depth} = 0;
2752 elsif ($attrs->{from}) { #shallow copy suffices
2753 $from = [ @{$attrs->{from}} ];
2757 -source_handle => $source->handle,
2758 -alias => $attrs->{alias},
2759 $attrs->{alias} => $source->from,
2763 my $jpath = ($seen->{-relation_chain_depth})
2764 ? $from->[-1][0]{-join_path}
2767 my @requested_joins = $source->_resolve_join(
2774 push @$from, @requested_joins;
2776 $seen->{-relation_chain_depth}++;
2778 # if $self already had a join/prefetch specified on it, the requested
2779 # $rel might very well be already included. What we do in this case
2780 # is effectively a no-op (except that we bump up the chain_depth on
2781 # the join in question so we could tell it *is* the search_related)
2784 # we consider the last one thus reverse
2785 for my $j (reverse @requested_joins) {
2786 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
2787 if ($rel eq $last_j) {
2788 $j->[0]{-relation_chain_depth}++;
2794 unless ($already_joined) {
2795 push @$from, $source->_resolve_join(
2803 $seen->{-relation_chain_depth}++;
2805 return {%$attrs, from => $from, seen_join => $seen};
2808 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
2809 sub _resolved_attrs_copy {
2811 return { %{$self->_resolved_attrs (@_)} };
2814 sub _resolved_attrs {
2816 return $self->{_attrs} if $self->{_attrs};
2818 my $attrs = { %{ $self->{attrs} || {} } };
2819 my $source = $self->result_source;
2820 my $alias = $attrs->{alias};
2822 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
2825 # build columns (as long as select isn't set) into a set of as/select hashes
2826 unless ( $attrs->{select} ) {
2829 if ( ref $attrs->{columns} eq 'ARRAY' ) {
2830 @cols = @{ delete $attrs->{columns}}
2831 } elsif ( defined $attrs->{columns} ) {
2832 @cols = delete $attrs->{columns}
2834 @cols = $source->columns
2838 if ( ref $_ eq 'HASH' ) {
2841 my $key = /^\Q${alias}.\E(.+)$/
2847 push @colbits, { $key => $value };
2852 # add the additional columns on
2853 foreach (qw{include_columns +columns}) {
2854 if ( $attrs->{$_} ) {
2855 my @list = ( ref($attrs->{$_}) eq 'ARRAY' )
2856 ? @{ delete $attrs->{$_} }
2857 : delete $attrs->{$_};
2859 if ( ref($_) eq 'HASH' ) {
2862 my $key = ( split /\./, $_ )[-1];
2863 my $value = ( /\./ ? $_ : "$alias.$_" );
2864 push @colbits, { $key => $value };
2870 # start with initial select items
2871 if ( $attrs->{select} ) {
2873 ( ref $attrs->{select} eq 'ARRAY' )
2874 ? [ @{ $attrs->{select} } ]
2875 : [ $attrs->{select} ];
2877 if ( $attrs->{as} ) {
2880 ref $attrs->{as} eq 'ARRAY'
2881 ? [ @{ $attrs->{as} } ]
2885 $attrs->{as} = [ map {
2886 m/^\Q${alias}.\E(.+)$/
2889 } @{ $attrs->{select} }
2895 # otherwise we intialise select & as to empty
2896 $attrs->{select} = [];
2900 # now add colbits to select/as
2901 push @{ $attrs->{select} }, map values %{$_}, @colbits;
2902 push @{ $attrs->{as} }, map keys %{$_}, @colbits;
2904 if ( my $adds = delete $attrs->{'+select'} ) {
2905 $adds = [$adds] unless ref $adds eq 'ARRAY';
2906 push @{ $attrs->{select} },
2907 map { /\./ || ref $_ ? $_ : "$alias.$_" } @$adds;
2909 if ( my $adds = delete $attrs->{'+as'} ) {
2910 $adds = [$adds] unless ref $adds eq 'ARRAY';
2911 push @{ $attrs->{as} }, @$adds;
2914 $attrs->{from} ||= [{
2915 -source_handle => $source->handle,
2916 -alias => $self->{attrs}{alias},
2917 $self->{attrs}{alias} => $source->from,
2920 if ( $attrs->{join} || $attrs->{prefetch} ) {
2922 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
2923 if ref $attrs->{from} ne 'ARRAY';
2925 my $join = delete $attrs->{join} || {};
2927 if ( defined $attrs->{prefetch} ) {
2928 $join = $self->_merge_attr( $join, $attrs->{prefetch} );
2931 $attrs->{from} = # have to copy here to avoid corrupting the original
2933 @{ $attrs->{from} },
2934 $source->_resolve_join(
2937 { %{ $attrs->{seen_join} || {} } },
2938 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
2939 ? $attrs->{from}[-1][0]{-join_path}
2946 if ( defined $attrs->{order_by} ) {
2947 $attrs->{order_by} = (
2948 ref( $attrs->{order_by} ) eq 'ARRAY'
2949 ? [ @{ $attrs->{order_by} } ]
2950 : [ $attrs->{order_by} || () ]
2954 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
2955 $attrs->{group_by} = [ $attrs->{group_by} ];
2958 # generate the distinct induced group_by early, as prefetch will be carried via a
2959 # subquery (since a group_by is present)
2960 if (delete $attrs->{distinct}) {
2961 if ($attrs->{group_by}) {
2962 carp ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
2965 $attrs->{group_by} = [ grep { !ref($_) || (ref($_) ne 'HASH') } @{$attrs->{select}} ];
2967 # add any order_by parts that are not already present in the group_by
2968 # we need to be careful not to add any named functions/aggregates
2969 # i.e. select => [ ... { count => 'foo', -as 'foocount' } ... ]
2970 my %already_grouped = map { $_ => 1 } (@{$attrs->{group_by}});
2972 my $storage = $self->result_source->schema->storage;
2974 my $rs_column_list = $storage->_resolve_column_info ($attrs->{from});
2976 for my $chunk ($storage->_parse_order_by($attrs->{order_by})) {
2977 if ($rs_column_list->{$chunk} && not $already_grouped{$chunk}++) {
2978 push @{$attrs->{group_by}}, $chunk;
2984 $attrs->{collapse} ||= {};
2985 if ( my $prefetch = delete $attrs->{prefetch} ) {
2986 $prefetch = $self->_merge_attr( {}, $prefetch );
2988 my $prefetch_ordering = [];
2990 # this is a separate structure (we don't look in {from} directly)
2991 # as the resolver needs to shift things off the lists to work
2992 # properly (identical-prefetches on different branches)
2994 if (ref $attrs->{from} eq 'ARRAY') {
2996 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
2998 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
2999 next unless $j->[0]{-alias};
3000 next unless $j->[0]{-join_path};
3001 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3003 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3006 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3007 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3012 $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
3014 # we need to somehow mark which columns came from prefetch
3015 $attrs->{_prefetch_select} = [ map { $_->[0] } @prefetch ];
3017 push @{ $attrs->{select} }, @{$attrs->{_prefetch_select}};
3018 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
3020 push( @{$attrs->{order_by}}, @$prefetch_ordering );
3021 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
3024 # if both page and offset are specified, produce a combined offset
3025 # even though it doesn't make much sense, this is what pre 081xx has
3027 if (my $page = delete $attrs->{page}) {
3029 ($attrs->{rows} * ($page - 1))
3031 ($attrs->{offset} || 0)
3035 return $self->{_attrs} = $attrs;
3039 my ($self, $attr) = @_;
3041 if (ref $attr eq 'HASH') {
3042 return $self->_rollout_hash($attr);
3043 } elsif (ref $attr eq 'ARRAY') {
3044 return $self->_rollout_array($attr);
3050 sub _rollout_array {
3051 my ($self, $attr) = @_;
3054 foreach my $element (@{$attr}) {
3055 if (ref $element eq 'HASH') {
3056 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3057 } elsif (ref $element eq 'ARRAY') {
3058 # XXX - should probably recurse here
3059 push( @rolled_array, @{$self->_rollout_array($element)} );
3061 push( @rolled_array, $element );
3064 return \@rolled_array;
3068 my ($self, $attr) = @_;
3071 foreach my $key (keys %{$attr}) {
3072 push( @rolled_array, { $key => $attr->{$key} } );
3074 return \@rolled_array;
3077 sub _calculate_score {
3078 my ($self, $a, $b) = @_;
3080 if (defined $a xor defined $b) {
3083 elsif (not defined $a) {
3087 if (ref $b eq 'HASH') {
3088 my ($b_key) = keys %{$b};
3089 if (ref $a eq 'HASH') {
3090 my ($a_key) = keys %{$a};
3091 if ($a_key eq $b_key) {
3092 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3097 return ($a eq $b_key) ? 1 : 0;
3100 if (ref $a eq 'HASH') {
3101 my ($a_key) = keys %{$a};
3102 return ($b eq $a_key) ? 1 : 0;
3104 return ($b eq $a) ? 1 : 0;
3110 my ($self, $orig, $import) = @_;
3112 return $import unless defined($orig);
3113 return $orig unless defined($import);
3115 $orig = $self->_rollout_attr($orig);
3116 $import = $self->_rollout_attr($import);
3119 foreach my $import_element ( @{$import} ) {
3120 # find best candidate from $orig to merge $b_element into
3121 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3122 foreach my $orig_element ( @{$orig} ) {
3123 my $score = $self->_calculate_score( $orig_element, $import_element );
3124 if ($score > $best_candidate->{score}) {
3125 $best_candidate->{position} = $position;
3126 $best_candidate->{score} = $score;
3130 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3132 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3133 push( @{$orig}, $import_element );
3135 my $orig_best = $orig->[$best_candidate->{position}];
3136 # merge orig_best and b_element together and replace original with merged
3137 if (ref $orig_best ne 'HASH') {
3138 $orig->[$best_candidate->{position}] = $import_element;
3139 } elsif (ref $import_element eq 'HASH') {
3140 my ($key) = keys %{$orig_best};
3141 $orig->[$best_candidate->{position}] = { $key => $self->_merge_attr($orig_best->{$key}, $import_element->{$key}) };
3144 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3154 $self->_source_handle($_[0]->handle);
3156 $self->_source_handle->resolve;
3160 =head2 throw_exception
3162 See L<DBIx::Class::Schema/throw_exception> for details.
3166 sub throw_exception {
3169 if (ref $self && $self->_source_handle->schema) {
3170 $self->_source_handle->schema->throw_exception(@_)
3173 DBIx::Class::Exception->throw(@_);
3177 # XXX: FIXME: Attributes docs need clearing up
3181 Attributes are used to refine a ResultSet in various ways when
3182 searching for data. They can be passed to any method which takes an
3183 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3186 These are in no particular order:
3192 =item Value: ( $order_by | \@order_by | \%order_by )
3196 Which column(s) to order the results by.
3198 [The full list of suitable values is documented in
3199 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3202 If a single column name, or an arrayref of names is supplied, the
3203 argument is passed through directly to SQL. The hashref syntax allows
3204 for connection-agnostic specification of ordering direction:
3206 For descending order:
3208 order_by => { -desc => [qw/col1 col2 col3/] }
3210 For explicit ascending order:
3212 order_by => { -asc => 'col' }
3214 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3215 supported, although you are strongly encouraged to use the hashref
3216 syntax as outlined above.
3222 =item Value: \@columns
3226 Shortcut to request a particular set of columns to be retrieved. Each
3227 column spec may be a string (a table column name), or a hash (in which
3228 case the key is the C<as> value, and the value is used as the C<select>
3229 expression). Adds C<me.> onto the start of any column without a C<.> in
3230 it and sets C<select> from that, then auto-populates C<as> from
3231 C<select> as normal. (You may also use the C<cols> attribute, as in
3232 earlier versions of DBIC.)
3238 =item Value: \@columns
3242 Indicates additional columns to be selected from storage. Works the same
3243 as L</columns> but adds columns to the selection. (You may also use the
3244 C<include_columns> attribute, as in earlier versions of DBIC). For
3247 $schema->resultset('CD')->search(undef, {
3248 '+columns' => ['artist.name'],
3252 would return all CDs and include a 'name' column to the information
3253 passed to object inflation. Note that the 'artist' is the name of the
3254 column (or relationship) accessor, and 'name' is the name of the column
3255 accessor in the related table.
3257 =head2 include_columns
3261 =item Value: \@columns
3265 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3271 =item Value: \@select_columns
3275 Indicates which columns should be selected from the storage. You can use
3276 column names, or in the case of RDBMS back ends, function or stored procedure
3279 $rs = $schema->resultset('Employee')->search(undef, {
3282 { count => 'employeeid' },
3283 { max => { length => 'name' }, -as => 'longest_name' }
3288 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
3290 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
3291 use L</select>, to instruct DBIx::Class how to store the result of the column.
3292 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
3293 identifier aliasing. You can however alias a function, so you can use it in
3294 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
3295 attribute> supplied as shown in the example above.
3301 Indicates additional columns to be selected from storage. Works the same as
3302 L</select> but adds columns to the default selection, instead of specifying
3311 Indicates additional column names for those added via L</+select>. See L</as>.
3319 =item Value: \@inflation_names
3323 Indicates column names for object inflation. That is L</as> indicates the
3324 slot name in which the column value will be stored within the
3325 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
3326 identifier by the C<get_column> method (or via the object accessor B<if one
3327 with the same name already exists>) as shown below. The L</as> attribute has
3328 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
3330 $rs = $schema->resultset('Employee')->search(undef, {
3333 { count => 'employeeid' },
3334 { max => { length => 'name' }, -as => 'longest_name' }
3343 If the object against which the search is performed already has an accessor
3344 matching a column name specified in C<as>, the value can be retrieved using
3345 the accessor as normal:
3347 my $name = $employee->name();
3349 If on the other hand an accessor does not exist in the object, you need to
3350 use C<get_column> instead:
3352 my $employee_count = $employee->get_column('employee_count');
3354 You can create your own accessors if required - see
3355 L<DBIx::Class::Manual::Cookbook> for details.
3361 =item Value: ($rel_name | \@rel_names | \%rel_names)
3365 Contains a list of relationships that should be joined for this query. For
3368 # Get CDs by Nine Inch Nails
3369 my $rs = $schema->resultset('CD')->search(
3370 { 'artist.name' => 'Nine Inch Nails' },
3371 { join => 'artist' }
3374 Can also contain a hash reference to refer to the other relation's relations.
3377 package MyApp::Schema::Track;
3378 use base qw/DBIx::Class/;
3379 __PACKAGE__->table('track');
3380 __PACKAGE__->add_columns(qw/trackid cd position title/);
3381 __PACKAGE__->set_primary_key('trackid');
3382 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3385 # In your application
3386 my $rs = $schema->resultset('Artist')->search(
3387 { 'track.title' => 'Teardrop' },
3389 join => { cd => 'track' },
3390 order_by => 'artist.name',
3394 You need to use the relationship (not the table) name in conditions,
3395 because they are aliased as such. The current table is aliased as "me", so
3396 you need to use me.column_name in order to avoid ambiguity. For example:
3398 # Get CDs from 1984 with a 'Foo' track
3399 my $rs = $schema->resultset('CD')->search(
3402 'tracks.name' => 'Foo'
3404 { join => 'tracks' }
3407 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3408 similarly for a third time). For e.g.
3410 my $rs = $schema->resultset('Artist')->search({
3411 'cds.title' => 'Down to Earth',
3412 'cds_2.title' => 'Popular',
3414 join => [ qw/cds cds/ ],
3417 will return a set of all artists that have both a cd with title 'Down
3418 to Earth' and a cd with title 'Popular'.
3420 If you want to fetch related objects from other tables as well, see C<prefetch>
3423 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3429 =item Value: ($rel_name | \@rel_names | \%rel_names)
3433 Contains one or more relationships that should be fetched along with
3434 the main query (when they are accessed afterwards the data will
3435 already be available, without extra queries to the database). This is
3436 useful for when you know you will need the related objects, because it
3437 saves at least one query:
3439 my $rs = $schema->resultset('Tag')->search(
3448 The initial search results in SQL like the following:
3450 SELECT tag.*, cd.*, artist.* FROM tag
3451 JOIN cd ON tag.cd = cd.cdid
3452 JOIN artist ON cd.artist = artist.artistid
3454 L<DBIx::Class> has no need to go back to the database when we access the
3455 C<cd> or C<artist> relationships, which saves us two SQL statements in this
3458 Simple prefetches will be joined automatically, so there is no need
3459 for a C<join> attribute in the above search.
3461 C<prefetch> can be used with the following relationship types: C<belongs_to>,
3462 C<has_one> (or if you're using C<add_relationship>, any relationship declared
3463 with an accessor type of 'single' or 'filter'). A more complex example that
3464 prefetches an artists cds, the tracks on those cds, and the tags associated
3465 with that artist is given below (assuming many-to-many from artists to tags):
3467 my $rs = $schema->resultset('Artist')->search(
3471 { cds => 'tracks' },
3472 { artist_tags => 'tags' }
3478 B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
3479 attributes will be ignored.
3481 B<CAVEATs>: Prefetch does a lot of deep magic. As such, it may not behave
3482 exactly as you might expect.
3488 Prefetch uses the L</cache> to populate the prefetched relationships. This
3489 may or may not be what you want.
3493 If you specify a condition on a prefetched relationship, ONLY those
3494 rows that match the prefetched condition will be fetched into that relationship.
3495 This means that adding prefetch to a search() B<may alter> what is returned by
3496 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
3498 my $artist_rs = $schema->resultset('Artist')->search({
3504 my $count = $artist_rs->first->cds->count;
3506 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
3508 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
3510 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
3512 that cmp_ok() may or may not pass depending on the datasets involved. This
3513 behavior may or may not survive the 0.09 transition.
3525 Makes the resultset paged and specifies the page to retrieve. Effectively
3526 identical to creating a non-pages resultset and then calling ->page($page)
3529 If L<rows> attribute is not specified it defaults to 10 rows per page.
3531 When you have a paged resultset, L</count> will only return the number
3532 of rows in the page. To get the total, use the L</pager> and call
3533 C<total_entries> on it.
3543 Specifies the maximum number of rows for direct retrieval or the number of
3544 rows per page if the page attribute or method is used.
3550 =item Value: $offset
3554 Specifies the (zero-based) row number for the first row to be returned, or the
3555 of the first row of the first page if paging is used.
3561 =item Value: \@columns
3565 A arrayref of columns to group by. Can include columns of joined tables.
3567 group_by => [qw/ column1 column2 ... /]
3573 =item Value: $condition
3577 HAVING is a select statement attribute that is applied between GROUP BY and
3578 ORDER BY. It is applied to the after the grouping calculations have been
3581 having => { 'count(employee)' => { '>=', 100 } }
3587 =item Value: (0 | 1)
3591 Set to 1 to group by all columns. If the resultset already has a group_by
3592 attribute, this setting is ignored and an appropriate warning is issued.
3598 Adds to the WHERE clause.
3600 # only return rows WHERE deleted IS NULL for all searches
3601 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
3603 Can be overridden by passing C<< { where => undef } >> as an attribute
3610 Set to 1 to cache search results. This prevents extra SQL queries if you
3611 revisit rows in your ResultSet:
3613 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
3615 while( my $artist = $resultset->next ) {
3619 $rs->first; # without cache, this would issue a query
3621 By default, searches are not cached.
3623 For more examples of using these attributes, see
3624 L<DBIx::Class::Manual::Cookbook>.
3630 =item Value: ( 'update' | 'shared' )
3634 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT