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 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
29 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
33 A ResultSet is an object which stores a set of conditions representing
34 a query. It is the backbone of DBIx::Class (i.e. the really
35 important/useful bit).
37 No SQL is executed on the database when a ResultSet is created, it
38 just stores all the conditions needed to create the query.
40 A basic ResultSet representing the data of an entire table is returned
41 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
42 L<Source|DBIx::Class::Manual::Glossary/Source> name.
44 my $users_rs = $schema->resultset('User');
46 A new ResultSet is returned from calling L</search> on an existing
47 ResultSet. The new one will contain all the conditions of the
48 original, plus any new conditions added in the C<search> call.
50 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
51 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
54 The query that the ResultSet represents is B<only> executed against
55 the database when these methods are called:
56 L</find> L</next> L</all> L</first> L</single> L</count>
60 =head2 Chaining resultsets
62 Let's say you've got a query that needs to be run to return some data
63 to the user. But, you have an authorization system in place that
64 prevents certain users from seeing certain information. So, you want
65 to construct the basic query in one method, but add constraints to it in
70 my $request = $self->get_request; # Get a request object somehow.
71 my $schema = $self->get_schema; # Get the DBIC schema object somehow.
73 my $cd_rs = $schema->resultset('CD')->search({
74 title => $request->param('title'),
75 year => $request->param('year'),
78 $self->apply_security_policy( $cd_rs );
83 sub apply_security_policy {
92 =head3 Resolving conditions and attributes
94 When a resultset is chained from another resultset, conditions and
95 attributes with the same keys need resolving.
97 L</join>, L</prefetch>, L</+select>, L</+as> attributes are merged
98 into the existing ones from the original resultset.
100 The L</where>, L</having> attribute, and any search conditions are
101 merged with an SQL C<AND> to the existing condition from the original
104 All other attributes are overridden by any new ones supplied in the
107 =head2 Multiple queries
109 Since a resultset just defines a query, you can do all sorts of
110 things with it with the same object.
112 # Don't hit the DB yet.
113 my $cd_rs = $schema->resultset('CD')->search({
114 title => 'something',
118 # Each of these hits the DB individually.
119 my $count = $cd_rs->count;
120 my $most_recent = $cd_rs->get_column('date_released')->max();
121 my @records = $cd_rs->all;
123 And it's not just limited to SELECT statements.
129 $cd_rs->create({ artist => 'Fred' });
131 Which is the same as:
133 $schema->resultset('CD')->create({
134 title => 'something',
139 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
143 If a resultset is used in a numeric context it returns the L</count>.
144 However, if it is used in a booleand context it is always true. So if
145 you want to check if a resultset has any results use C<if $rs != 0>.
146 C<if $rs> will always be true.
154 =item Arguments: $source, \%$attrs
156 =item Return Value: $rs
160 The resultset constructor. Takes a source object (usually a
161 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
162 L</ATTRIBUTES> below). Does not perform any queries -- these are
163 executed as needed by the other methods.
165 Generally you won't need to construct a resultset manually. You'll
166 automatically get one from e.g. a L</search> called in scalar context:
168 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
170 IMPORTANT: If called on an object, proxies to new_result instead so
172 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
174 will return a CD object, not a ResultSet.
180 return $class->new_result(@_) if ref $class;
182 my ($source, $attrs) = @_;
183 $source = $source->handle
184 unless $source->isa('DBIx::Class::ResultSourceHandle');
185 $attrs = { %{$attrs||{}} };
187 if ($attrs->{page}) {
188 $attrs->{rows} ||= 10;
191 $attrs->{alias} ||= 'me';
193 # Creation of {} and bless separated to mitigate RH perl bug
194 # see https://bugzilla.redhat.com/show_bug.cgi?id=196836
196 _source_handle => $source,
197 cond => $attrs->{where},
206 $attrs->{result_class} || $source->resolve->result_class
216 =item Arguments: $cond, \%attrs?
218 =item Return Value: $resultset (scalar context), @row_objs (list context)
222 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
223 my $new_rs = $cd_rs->search({ year => 2005 });
225 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
226 # year = 2005 OR year = 2004
228 If you need to pass in additional attributes but no additional condition,
229 call it as C<search(undef, \%attrs)>.
231 # "SELECT name, artistid FROM $artist_table"
232 my @all_artists = $schema->resultset('Artist')->search(undef, {
233 columns => [qw/name artistid/],
236 For a list of attributes that can be passed to C<search>, see
237 L</ATTRIBUTES>. For more examples of using this function, see
238 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
239 documentation for the first argument, see L<SQL::Abstract>.
241 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
247 my $rs = $self->search_rs( @_ );
248 return (wantarray ? $rs->all : $rs);
255 =item Arguments: $cond, \%attrs?
257 =item Return Value: $resultset
261 This method does the same exact thing as search() except it will
262 always return a resultset, even in list context.
269 # Special-case handling for (undef, undef).
270 if ( @_ == 2 && !defined $_[1] && !defined $_[0] ) {
275 $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
276 my $our_attrs = { %{$self->{attrs}} };
277 my $having = delete $our_attrs->{having};
278 my $where = delete $our_attrs->{where};
282 my %safe = (alias => 1, cache => 1);
285 (@_ && defined($_[0])) # @_ == () or (undef)
287 (keys %$attrs # empty attrs or only 'safe' attrs
288 && List::Util::first { !$safe{$_} } keys %$attrs)
290 # no search, effectively just a clone
291 $rows = $self->get_cache;
294 my $new_attrs = { %{$our_attrs}, %{$attrs} };
296 # merge new attrs into inherited
297 foreach my $key (qw/join prefetch +select +as bind/) {
298 next unless exists $attrs->{$key};
299 $new_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key});
304 (@_ == 1 || ref $_[0] eq "HASH")
306 (ref $_[0] eq 'HASH')
308 (keys %{ $_[0] } > 0)
316 ? $self->throw_exception("Odd number of arguments to search")
323 if (defined $where) {
324 $new_attrs->{where} = (
325 defined $new_attrs->{where}
328 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
329 } $where, $new_attrs->{where}
336 $new_attrs->{where} = (
337 defined $new_attrs->{where}
340 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
341 } $cond, $new_attrs->{where}
347 if (defined $having) {
348 $new_attrs->{having} = (
349 defined $new_attrs->{having}
352 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
353 } $having, $new_attrs->{having}
359 my $rs = (ref $self)->new($self->result_source, $new_attrs);
361 $rs->set_cache($rows) if ($rows);
366 =head2 search_literal
370 =item Arguments: $sql_fragment, @bind_values
372 =item Return Value: $resultset (scalar context), @row_objs (list context)
376 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
377 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
379 Pass a literal chunk of SQL to be added to the conditional part of the
382 CAVEAT: C<search_literal> is provided for Class::DBI compatibility and should
383 only be used in that context. C<search_literal> is a convenience method.
384 It is equivalent to calling $schema->search(\[]), but if you want to ensure
385 columns are bound correctly, use C<search>.
387 Example of how to use C<search> instead of C<search_literal>
389 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
390 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
393 See L<DBIx::Class::Manual::Cookbook/Searching> and
394 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
395 require C<search_literal>.
400 my ($self, $sql, @bind) = @_;
402 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
405 return $self->search(\[ $sql, map [ __DUMMY__ => $_ ], @bind ], ($attr || () ));
412 =item Arguments: @values | \%cols, \%attrs?
414 =item Return Value: $row_object | undef
418 Finds a row based on its primary key or unique constraint. For example, to find
419 a row by its primary key:
421 my $cd = $schema->resultset('CD')->find(5);
423 You can also find a row by a specific unique constraint using the C<key>
424 attribute. For example:
426 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
427 key => 'cd_artist_title'
430 Additionally, you can specify the columns explicitly by name:
432 my $cd = $schema->resultset('CD')->find(
434 artist => 'Massive Attack',
435 title => 'Mezzanine',
437 { key => 'cd_artist_title' }
440 If the C<key> is specified as C<primary>, it searches only on the primary key.
442 If no C<key> is specified, it searches on all unique constraints defined on the
443 source for which column data is provided, including the primary key.
445 If your table does not have a primary key, you B<must> provide a value for the
446 C<key> attribute matching one of the unique constraints on the source.
448 In addition to C<key>, L</find> recognizes and applies standard
449 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
451 Note: If your query does not return only one row, a warning is generated:
453 Query returned more than one row
455 See also L</find_or_create> and L</update_or_create>. For information on how to
456 declare unique constraints, see
457 L<DBIx::Class::ResultSource/add_unique_constraint>.
463 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
465 # Default to the primary key, but allow a specific key
466 my @cols = exists $attrs->{key}
467 ? $self->result_source->unique_constraint_columns($attrs->{key})
468 : $self->result_source->primary_columns;
469 $self->throw_exception(
470 "Can't find unless a primary key is defined or unique constraint is specified"
473 # Parse out a hashref from input
475 if (ref $_[0] eq 'HASH') {
476 $input_query = { %{$_[0]} };
478 elsif (@_ == @cols) {
480 @{$input_query}{@cols} = @_;
483 # Compatibility: Allow e.g. find(id => $value)
484 carp "Find by key => value deprecated; please use a hashref instead";
488 my (%related, $info);
490 KEY: foreach my $key (keys %$input_query) {
491 if (ref($input_query->{$key})
492 && ($info = $self->result_source->relationship_info($key))) {
493 my $val = delete $input_query->{$key};
494 next KEY if (ref($val) eq 'ARRAY'); # has_many for multi_create
495 my $rel_q = $self->result_source->_resolve_condition(
496 $info->{cond}, $val, $key
498 die "Can't handle OR join condition in find" if ref($rel_q) eq 'ARRAY';
499 @related{keys %$rel_q} = values %$rel_q;
502 if (my @keys = keys %related) {
503 @{$input_query}{@keys} = values %related;
507 # Build the final query: Default to the disjunction of the unique queries,
508 # but allow the input query in case the ResultSet defines the query or the
509 # user is abusing find
510 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
512 if (exists $attrs->{key}) {
513 my @unique_cols = $self->result_source->unique_constraint_columns($attrs->{key});
514 my $unique_query = $self->_build_unique_query($input_query, \@unique_cols);
515 $query = $self->_add_alias($unique_query, $alias);
517 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
518 # This means that we got here after a merger of relationship conditions
519 # in ::Relationship::Base::search_related (the row method), and furthermore
520 # the relationship is of the 'single' type. This means that the condition
521 # provided by the relationship (already attached to $self) is sufficient,
522 # as there can be only one row in the databse that would satisfy the
526 my @unique_queries = $self->_unique_queries($input_query, $attrs);
527 $query = @unique_queries
528 ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
529 : $self->_add_alias($input_query, $alias);
533 my $rs = $self->search ($query, {result_class => $self->result_class, %$attrs});
534 if (keys %{$rs->_resolved_attrs->{collapse}}) {
536 carp "Query returned more than one row" if $rs->next;
546 # Add the specified alias to the specified query hash. A copy is made so the
547 # original query is not modified.
550 my ($self, $query, $alias) = @_;
552 my %aliased = %$query;
553 foreach my $col (grep { ! m/\./ } keys %aliased) {
554 $aliased{"$alias.$col"} = delete $aliased{$col};
562 # Build a list of queries which satisfy unique constraints.
564 sub _unique_queries {
565 my ($self, $query, $attrs) = @_;
567 my @constraint_names = exists $attrs->{key}
569 : $self->result_source->unique_constraint_names;
571 my $where = $self->_collapse_cond($self->{attrs}{where} || {});
572 my $num_where = scalar keys %$where;
574 my (@unique_queries, %seen_column_combinations);
575 foreach my $name (@constraint_names) {
576 my @constraint_cols = $self->result_source->unique_constraint_columns($name);
578 my $constraint_sig = join "\x00", sort @constraint_cols;
579 next if $seen_column_combinations{$constraint_sig}++;
581 my $unique_query = $self->_build_unique_query($query, \@constraint_cols);
583 my $num_cols = scalar @constraint_cols;
584 my $num_query = scalar keys %$unique_query;
586 my $total = $num_query + $num_where;
587 if ($num_query && ($num_query == $num_cols || $total == $num_cols)) {
588 # The query is either unique on its own or is unique in combination with
589 # the existing where clause
590 push @unique_queries, $unique_query;
594 return @unique_queries;
597 # _build_unique_query
599 # Constrain the specified query hash based on the specified column names.
601 sub _build_unique_query {
602 my ($self, $query, $unique_cols) = @_;
605 map { $_ => $query->{$_} }
606 grep { exists $query->{$_} }
611 =head2 search_related
615 =item Arguments: $rel, $cond, \%attrs?
617 =item Return Value: $new_resultset
621 $new_rs = $cd_rs->search_related('artist', {
625 Searches the specified relationship, optionally specifying a condition and
626 attributes for matching records. See L</ATTRIBUTES> for more information.
631 return shift->related_resultset(shift)->search(@_);
634 =head2 search_related_rs
636 This method works exactly the same as search_related, except that
637 it guarantees a restultset, even in list context.
641 sub search_related_rs {
642 return shift->related_resultset(shift)->search_rs(@_);
649 =item Arguments: none
651 =item Return Value: $cursor
655 Returns a storage-driven cursor to the given resultset. See
656 L<DBIx::Class::Cursor> for more information.
663 my $attrs = $self->_resolved_attrs_copy;
665 return $self->{cursor}
666 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
667 $attrs->{where},$attrs);
674 =item Arguments: $cond?
676 =item Return Value: $row_object?
680 my $cd = $schema->resultset('CD')->single({ year => 2001 });
682 Inflates the first result without creating a cursor if the resultset has
683 any records in it; if not returns nothing. Used by L</find> as a lean version of
686 While this method can take an optional search condition (just like L</search>)
687 being a fast-code-path it does not recognize search attributes. If you need to
688 add extra joins or similar, call L</search> and then chain-call L</single> on the
689 L<DBIx::Class::ResultSet> returned.
695 As of 0.08100, this method enforces the assumption that the preceeding
696 query returns only one row. If more than one row is returned, you will receive
699 Query returned more than one row
701 In this case, you should be using L</next> or L</find> instead, or if you really
702 know what you are doing, use the L</rows> attribute to explicitly limit the size
705 This method will also throw an exception if it is called on a resultset prefetching
706 has_many, as such a prefetch implies fetching multiple rows from the database in
707 order to assemble the resulting object.
714 my ($self, $where) = @_;
716 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
719 my $attrs = $self->_resolved_attrs_copy;
721 if (keys %{$attrs->{collapse}}) {
722 $self->throw_exception(
723 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
728 if (defined $attrs->{where}) {
731 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
732 $where, delete $attrs->{where} ]
735 $attrs->{where} = $where;
739 # XXX: Disabled since it doesn't infer uniqueness in all cases
740 # unless ($self->_is_unique_query($attrs->{where})) {
741 # carp "Query not guaranteed to return a single row"
742 # . "; please declare your unique constraints or use search instead";
745 my @data = $self->result_source->storage->select_single(
746 $attrs->{from}, $attrs->{select},
747 $attrs->{where}, $attrs
750 return (@data ? ($self->_construct_object(@data))[0] : undef);
756 # Try to determine if the specified query is guaranteed to be unique, based on
757 # the declared unique constraints.
759 sub _is_unique_query {
760 my ($self, $query) = @_;
762 my $collapsed = $self->_collapse_query($query);
763 my $alias = $self->{attrs}{alias};
765 foreach my $name ($self->result_source->unique_constraint_names) {
766 my @unique_cols = map {
768 } $self->result_source->unique_constraint_columns($name);
770 # Count the values for each unique column
771 my %seen = map { $_ => 0 } @unique_cols;
773 foreach my $key (keys %$collapsed) {
774 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
775 next unless exists $seen{$aliased}; # Additional constraints are okay
776 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
779 # If we get 0 or more than 1 value for a column, it's not necessarily unique
780 return 1 unless grep { $_ != 1 } values %seen;
788 # Recursively collapse the query, accumulating values for each column.
790 sub _collapse_query {
791 my ($self, $query, $collapsed) = @_;
795 if (ref $query eq 'ARRAY') {
796 foreach my $subquery (@$query) {
797 next unless ref $subquery; # -or
798 $collapsed = $self->_collapse_query($subquery, $collapsed);
801 elsif (ref $query eq 'HASH') {
802 if (keys %$query and (keys %$query)[0] eq '-and') {
803 foreach my $subquery (@{$query->{-and}}) {
804 $collapsed = $self->_collapse_query($subquery, $collapsed);
808 foreach my $col (keys %$query) {
809 my $value = $query->{$col};
810 $collapsed->{$col}{$value}++;
822 =item Arguments: $cond?
824 =item Return Value: $resultsetcolumn
828 my $max_length = $rs->get_column('length')->max;
830 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
835 my ($self, $column) = @_;
836 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
844 =item Arguments: $cond, \%attrs?
846 =item Return Value: $resultset (scalar context), @row_objs (list context)
850 # WHERE title LIKE '%blue%'
851 $cd_rs = $rs->search_like({ title => '%blue%'});
853 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
854 that this is simply a convenience method retained for ex Class::DBI users.
855 You most likely want to use L</search> with specific operators.
857 For more information, see L<DBIx::Class::Manual::Cookbook>.
859 This method is deprecated and will be removed in 0.09. Use L</search()>
860 instead. An example conversion is:
862 ->search_like({ foo => 'bar' });
866 ->search({ foo => { like => 'bar' } });
873 'search_like() is deprecated and will be removed in DBIC version 0.09.'
874 .' Instead use ->search({ x => { -like => "y%" } })'
875 .' (note the outer pair of {}s - they are important!)'
877 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
878 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
879 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
880 return $class->search($query, { %$attrs });
887 =item Arguments: $first, $last
889 =item Return Value: $resultset (scalar context), @row_objs (list context)
893 Returns a resultset or object list representing a subset of elements from the
894 resultset slice is called on. Indexes are from 0, i.e., to get the first
897 my ($one, $two, $three) = $rs->slice(0, 2);
902 my ($self, $min, $max) = @_;
903 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
904 $attrs->{offset} = $self->{attrs}{offset} || 0;
905 $attrs->{offset} += $min;
906 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
907 return $self->search(undef(), $attrs);
908 #my $slice = (ref $self)->new($self->result_source, $attrs);
909 #return (wantarray ? $slice->all : $slice);
916 =item Arguments: none
918 =item Return Value: $result?
922 Returns the next element in the resultset (C<undef> is there is none).
924 Can be used to efficiently iterate over records in the resultset:
926 my $rs = $schema->resultset('CD')->search;
927 while (my $cd = $rs->next) {
931 Note that you need to store the resultset object, and call C<next> on it.
932 Calling C<< resultset('Table')->next >> repeatedly will always return the
933 first record from the resultset.
939 if (my $cache = $self->get_cache) {
940 $self->{all_cache_position} ||= 0;
941 return $cache->[$self->{all_cache_position}++];
943 if ($self->{attrs}{cache}) {
944 $self->{all_cache_position} = 1;
945 return ($self->all)[0];
947 if ($self->{stashed_objects}) {
948 my $obj = shift(@{$self->{stashed_objects}});
949 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
953 exists $self->{stashed_row}
954 ? @{delete $self->{stashed_row}}
955 : $self->cursor->next
957 return undef unless (@row);
958 my ($row, @more) = $self->_construct_object(@row);
959 $self->{stashed_objects} = \@more if @more;
963 sub _construct_object {
964 my ($self, @row) = @_;
966 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row)
968 my @new = $self->result_class->inflate_result($self->result_source, @$info);
969 @new = $self->{_attrs}{record_filter}->(@new)
970 if exists $self->{_attrs}{record_filter};
974 sub _collapse_result {
975 my ($self, $as_proto, $row) = @_;
977 # if the first row that ever came in is totally empty - this means we got
978 # hit by a smooth^Wempty left-joined resultset. Just noop in that case
979 # instead of producing a {}
988 return undef unless $has_def;
992 # 'foo' => [ undef, 'foo' ]
993 # 'foo.bar' => [ 'foo', 'bar' ]
994 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
996 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
998 my %collapse = %{$self->{_attrs}{collapse}||{}};
1002 # if we're doing collapsing (has_many prefetch) we need to grab records
1003 # until the PK changes, so fill @pri_index. if not, we leave it empty so
1004 # we know we don't have to bother.
1006 # the reason for not using the collapse stuff directly is because if you
1007 # had for e.g. two artists in a row with no cds, the collapse info for
1008 # both would be NULL (undef) so you'd lose the second artist
1010 # store just the index so we can check the array positions from the row
1011 # without having to contruct the full hash
1013 if (keys %collapse) {
1014 my %pri = map { ($_ => 1) } $self->result_source->primary_columns;
1015 foreach my $i (0 .. $#construct_as) {
1016 next if defined($construct_as[$i][0]); # only self table
1017 if (delete $pri{$construct_as[$i][1]}) {
1018 push(@pri_index, $i);
1020 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
1024 # no need to do an if, it'll be empty if @pri_index is empty anyway
1026 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
1030 do { # no need to check anything at the front, we always want the first row
1034 foreach my $this_as (@construct_as) {
1035 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
1038 push(@const_rows, \%const);
1040 } until ( # no pri_index => no collapse => drop straight out
1043 do { # get another row, stash it, drop out if different PK
1045 @copy = $self->cursor->next;
1046 $self->{stashed_row} = \@copy;
1048 # last thing in do block, counts as true if anything doesn't match
1050 # check xor defined first for NULL vs. NOT NULL then if one is
1051 # defined the other must be so check string equality
1054 (defined $pri_vals{$_} ^ defined $copy[$_])
1055 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
1060 my $alias = $self->{attrs}{alias};
1067 foreach my $const (@const_rows) {
1068 scalar @const_keys or do {
1069 @const_keys = sort { length($a) <=> length($b) } keys %$const;
1071 foreach my $key (@const_keys) {
1074 my @parts = split(/\./, $key);
1076 my $data = $const->{$key};
1077 foreach my $p (@parts) {
1078 $target = $target->[1]->{$p} ||= [];
1080 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
1081 # collapsing at this point and on final part
1082 my $pos = $collapse_pos{$cur};
1083 CK: foreach my $ck (@ckey) {
1084 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
1085 $collapse_pos{$cur} = $data;
1086 delete @collapse_pos{ # clear all positioning for sub-entries
1087 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
1094 if (exists $collapse{$cur}) {
1095 $target = $target->[-1];
1098 $target->[0] = $data;
1100 $info->[0] = $const->{$key};
1108 =head2 result_source
1112 =item Arguments: $result_source?
1114 =item Return Value: $result_source
1118 An accessor for the primary ResultSource object from which this ResultSet
1125 =item Arguments: $result_class?
1127 =item Return Value: $result_class
1131 An accessor for the class to use when creating row objects. Defaults to
1132 C<< result_source->result_class >> - which in most cases is the name of the
1133 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1135 Note that changing the result_class will also remove any components
1136 that were originally loaded in the source class via
1137 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1138 in the original source class will not run.
1143 my ($self, $result_class) = @_;
1144 if ($result_class) {
1145 $self->ensure_class_loaded($result_class);
1146 $self->_result_class($result_class);
1148 $self->_result_class;
1155 =item Arguments: $cond, \%attrs??
1157 =item Return Value: $count
1161 Performs an SQL C<COUNT> with the same query as the resultset was built
1162 with to find the number of elements. Passing arguments is equivalent to
1163 C<< $rs->search ($cond, \%attrs)->count >>
1169 return $self->search(@_)->count if @_ and defined $_[0];
1170 return scalar @{ $self->get_cache } if $self->get_cache;
1172 my $attrs = $self->_resolved_attrs_copy;
1174 # this is a little optimization - it is faster to do the limit
1175 # adjustments in software, instead of a subquery
1176 my $rows = delete $attrs->{rows};
1177 my $offset = delete $attrs->{offset};
1180 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1181 $crs = $self->_count_subq_rs ($attrs);
1184 $crs = $self->_count_rs ($attrs);
1186 my $count = $crs->next;
1188 $count -= $offset if $offset;
1189 $count = $rows if $rows and $rows < $count;
1190 $count = 0 if ($count < 0);
1199 =item Arguments: $cond, \%attrs??
1201 =item Return Value: $count_rs
1205 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1206 This can be very handy for subqueries:
1208 ->search( { amount => $some_rs->count_rs->as_query } )
1210 As with regular resultsets the SQL query will be executed only after
1211 the resultset is accessed via L</next> or L</all>. That would return
1212 the same single value obtainable via L</count>.
1218 return $self->search(@_)->count_rs if @_;
1220 # this may look like a lack of abstraction (count() does about the same)
1221 # but in fact an _rs *must* use a subquery for the limits, as the
1222 # software based limiting can not be ported if this $rs is to be used
1223 # in a subquery itself (i.e. ->as_query)
1224 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1225 return $self->_count_subq_rs;
1228 return $self->_count_rs;
1233 # returns a ResultSetColumn object tied to the count query
1236 my ($self, $attrs) = @_;
1238 my $rsrc = $self->result_source;
1239 $attrs ||= $self->_resolved_attrs;
1241 my $tmp_attrs = { %$attrs };
1243 # take off any limits, record_filter is cdbi, and no point of ordering a count
1244 delete $tmp_attrs->{$_} for (qw/select as rows offset order_by record_filter/);
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 # read the comment on top of the actual function to see what this does
1251 $tmp_attrs->{from} = $self->result_source->schema->storage->_straight_join_to_node (
1252 $tmp_attrs->{from}, $tmp_attrs->{alias}
1255 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1261 # same as above but uses a subquery
1263 sub _count_subq_rs {
1264 my ($self, $attrs) = @_;
1266 my $rsrc = $self->result_source;
1267 $attrs ||= $self->_resolved_attrs_copy;
1269 my $sub_attrs = { %$attrs };
1271 # extra selectors do not go in the subquery and there is no point of ordering it
1272 delete $sub_attrs->{$_} for qw/collapse select _prefetch_select as order_by/;
1274 # if we prefetch, we group_by primary keys only as this is what we would get out
1275 # of the rs via ->next/->all. We DO WANT to clobber old group_by regardless
1276 if ( keys %{$attrs->{collapse}} ) {
1277 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } ($rsrc->primary_columns) ]
1280 $sub_attrs->{select} = $rsrc->storage->_subq_count_select ($rsrc, $sub_attrs);
1282 # read the comment on top of the actual function to see what this does
1283 $sub_attrs->{from} = $self->result_source->schema->storage->_straight_join_to_node (
1284 $sub_attrs->{from}, $sub_attrs->{alias}
1287 # this is so that the query can be simplified e.g.
1288 # * non-limiting joins can be pruned
1289 # * ordering can be thrown away in things like Top limit
1290 $sub_attrs->{-for_count_only} = 1;
1292 my $sub_rs = $rsrc->resultset_class->new ($rsrc, $sub_attrs);
1295 -alias => 'count_subq',
1296 -source_handle => $rsrc->handle,
1297 count_subq => $sub_rs->as_query,
1300 # the subquery replaces this
1301 delete $attrs->{$_} for qw/where bind collapse group_by having having_bind rows offset/;
1303 return $self->_count_rs ($attrs);
1310 =head2 count_literal
1314 =item Arguments: $sql_fragment, @bind_values
1316 =item Return Value: $count
1320 Counts the results in a literal query. Equivalent to calling L</search_literal>
1321 with the passed arguments, then L</count>.
1325 sub count_literal { shift->search_literal(@_)->count; }
1331 =item Arguments: none
1333 =item Return Value: @objects
1337 Returns all elements in the resultset. Called implicitly if the resultset
1338 is returned in list context.
1345 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1348 return @{ $self->get_cache } if $self->get_cache;
1352 if (keys %{$self->_resolved_attrs->{collapse}}) {
1353 # Using $self->cursor->all is really just an optimisation.
1354 # If we're collapsing has_many prefetches it probably makes
1355 # very little difference, and this is cleaner than hacking
1356 # _construct_object to survive the approach
1357 $self->cursor->reset;
1358 my @row = $self->cursor->next;
1360 push(@obj, $self->_construct_object(@row));
1361 @row = (exists $self->{stashed_row}
1362 ? @{delete $self->{stashed_row}}
1363 : $self->cursor->next);
1366 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1369 $self->set_cache(\@obj) if $self->{attrs}{cache};
1378 =item Arguments: none
1380 =item Return Value: $self
1384 Resets the resultset's cursor, so you can iterate through the elements again.
1385 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1392 delete $self->{_attrs} if exists $self->{_attrs};
1393 $self->{all_cache_position} = 0;
1394 $self->cursor->reset;
1402 =item Arguments: none
1404 =item Return Value: $object?
1408 Resets the resultset and returns an object for the first result (if the
1409 resultset returns anything).
1414 return $_[0]->reset->next;
1420 # Determines whether and what type of subquery is required for the $rs operation.
1421 # If grouping is necessary either supplies its own, or verifies the current one
1422 # After all is done delegates to the proper storage method.
1424 sub _rs_update_delete {
1425 my ($self, $op, $values) = @_;
1427 my $rsrc = $self->result_source;
1429 # if a condition exists we need to strip all table qualifiers
1430 # if this is not possible we'll force a subquery below
1431 my $cond = $rsrc->schema->storage->_strip_cond_qualifiers ($self->{cond});
1433 my $needs_group_by_subq = $self->_has_resolved_attr (qw/collapse group_by -join/);
1434 my $needs_subq = (not defined $cond) || $self->_has_resolved_attr(qw/row offset/);
1436 if ($needs_group_by_subq or $needs_subq) {
1438 # make a new $rs selecting only the PKs (that's all we really need)
1439 my $attrs = $self->_resolved_attrs_copy;
1441 delete $attrs->{$_} for qw/collapse select as/;
1442 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->primary_columns) ];
1444 if ($needs_group_by_subq) {
1445 # make sure no group_by was supplied, or if there is one - make sure it matches
1446 # the columns compiled above perfectly. Anything else can not be sanely executed
1447 # on most databases so croak right then and there
1449 if (my $g = $attrs->{group_by}) {
1450 my @current_group_by = map
1451 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1456 join ("\x00", sort @current_group_by)
1458 join ("\x00", sort @{$attrs->{columns}} )
1460 $self->throw_exception (
1461 "You have just attempted a $op operation on a resultset which does group_by"
1462 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1463 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1464 . ' kind of queries. Please retry the operation with a modified group_by or'
1465 . ' without using one at all.'
1470 $attrs->{group_by} = $attrs->{columns};
1474 my $subrs = (ref $self)->new($rsrc, $attrs);
1476 return $self->result_source->storage->_subq_update_delete($subrs, $op, $values);
1479 return $rsrc->storage->$op(
1481 $op eq 'update' ? $values : (),
1491 =item Arguments: \%values
1493 =item Return Value: $storage_rv
1497 Sets the specified columns in the resultset to the supplied values in a
1498 single query. Return value will be true if the update succeeded or false
1499 if no records were updated; exact type of success value is storage-dependent.
1504 my ($self, $values) = @_;
1505 $self->throw_exception('Values for update must be a hash')
1506 unless ref $values eq 'HASH';
1508 return $self->_rs_update_delete ('update', $values);
1515 =item Arguments: \%values
1517 =item Return Value: 1
1521 Fetches all objects and updates them one at a time. Note that C<update_all>
1522 will run DBIC cascade triggers, while L</update> will not.
1527 my ($self, $values) = @_;
1528 $self->throw_exception('Values for update_all must be a hash')
1529 unless ref $values eq 'HASH';
1530 foreach my $obj ($self->all) {
1531 $obj->set_columns($values)->update;
1540 =item Arguments: none
1542 =item Return Value: $storage_rv
1546 Deletes the contents of the resultset from its result source. Note that this
1547 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1548 to run. See also L<DBIx::Class::Row/delete>.
1550 Return value will be the amount of rows deleted; exact type of return value
1551 is storage-dependent.
1557 $self->throw_exception('delete does not accept any arguments')
1560 return $self->_rs_update_delete ('delete');
1567 =item Arguments: none
1569 =item Return Value: 1
1573 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1574 will run DBIC cascade triggers, while L</delete> will not.
1580 $self->throw_exception('delete_all does not accept any arguments')
1583 $_->delete for $self->all;
1591 =item Arguments: \@data;
1595 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1596 For the arrayref of hashrefs style each hashref should be a structure suitable
1597 forsubmitting to a $resultset->create(...) method.
1599 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1600 to insert the data, as this is a faster method.
1602 Otherwise, each set of data is inserted into the database using
1603 L<DBIx::Class::ResultSet/create>, and the resulting objects are
1604 accumulated into an array. The array itself, or an array reference
1605 is returned depending on scalar or list context.
1607 Example: Assuming an Artist Class that has many CDs Classes relating:
1609 my $Artist_rs = $schema->resultset("Artist");
1611 ## Void Context Example
1612 $Artist_rs->populate([
1613 { artistid => 4, name => 'Manufactured Crap', cds => [
1614 { title => 'My First CD', year => 2006 },
1615 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1618 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1619 { title => 'My parents sold me to a record company' ,year => 2005 },
1620 { title => 'Why Am I So Ugly?', year => 2006 },
1621 { title => 'I Got Surgery and am now Popular', year => 2007 }
1626 ## Array Context Example
1627 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1628 { name => "Artist One"},
1629 { name => "Artist Two"},
1630 { name => "Artist Three", cds=> [
1631 { title => "First CD", year => 2007},
1632 { title => "Second CD", year => 2008},
1636 print $ArtistOne->name; ## response is 'Artist One'
1637 print $ArtistThree->cds->count ## reponse is '2'
1639 For the arrayref of arrayrefs style, the first element should be a list of the
1640 fieldsnames to which the remaining elements are rows being inserted. For
1643 $Arstist_rs->populate([
1644 [qw/artistid name/],
1645 [100, 'A Formally Unknown Singer'],
1646 [101, 'A singer that jumped the shark two albums ago'],
1647 [102, 'An actually cool singer.'],
1650 Please note an important effect on your data when choosing between void and
1651 wantarray context. Since void context goes straight to C<insert_bulk> in
1652 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
1653 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
1654 create primary keys for you, you will find that your PKs are empty. In this
1655 case you will have to use the wantarray context in order to create those
1661 my $self = shift @_;
1662 my $data = ref $_[0][0] eq 'HASH'
1663 ? $_[0] : ref $_[0][0] eq 'ARRAY' ? $self->_normalize_populate_args($_[0]) :
1664 $self->throw_exception('Populate expects an arrayref of hashes or arrayref of arrayrefs');
1666 if(defined wantarray) {
1668 foreach my $item (@$data) {
1669 push(@created, $self->create($item));
1671 return wantarray ? @created : \@created;
1673 my $first = $data->[0];
1675 # if a column is a registered relationship, and is a non-blessed hash/array, consider
1676 # it relationship data
1677 my (@rels, @columns);
1678 for (keys %$first) {
1679 my $ref = ref $first->{$_};
1680 $self->result_source->has_relationship($_) && ($ref eq 'ARRAY' or $ref eq 'HASH')
1686 my @pks = $self->result_source->primary_columns;
1688 ## do the belongs_to relationships
1689 foreach my $index (0..$#$data) {
1691 # delegate to create() for any dataset without primary keys with specified relationships
1692 if (grep { !defined $data->[$index]->{$_} } @pks ) {
1694 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
1695 my @ret = $self->populate($data);
1701 foreach my $rel (@rels) {
1702 next unless ref $data->[$index]->{$rel} eq "HASH";
1703 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1704 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1705 my $related = $result->result_source->_resolve_condition(
1706 $result->result_source->relationship_info($reverse)->{cond},
1711 delete $data->[$index]->{$rel};
1712 $data->[$index] = {%{$data->[$index]}, %$related};
1714 push @columns, keys %$related if $index == 0;
1718 ## inherit the data locked in the conditions of the resultset
1719 my ($rs_data) = $self->_merge_cond_with_data({});
1720 delete @{$rs_data}{@columns};
1721 my @inherit_cols = keys %$rs_data;
1722 my @inherit_data = values %$rs_data;
1724 ## do bulk insert on current row
1725 $self->result_source->storage->insert_bulk(
1726 $self->result_source,
1727 [@columns, @inherit_cols],
1728 [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
1731 ## do the has_many relationships
1732 foreach my $item (@$data) {
1734 foreach my $rel (@rels) {
1735 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1737 my $parent = $self->find({map { $_ => $item->{$_} } @pks})
1738 || $self->throw_exception('Cannot find the relating object.');
1740 my $child = $parent->$rel;
1742 my $related = $child->result_source->_resolve_condition(
1743 $parent->result_source->relationship_info($rel)->{cond},
1748 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1749 my @populate = map { {%$_, %$related} } @rows_to_add;
1751 $child->populate( \@populate );
1757 =head2 _normalize_populate_args ($args)
1759 Private method used by L</populate> to normalize its incoming arguments. Factored
1760 out in case you want to subclass and accept new argument structures to the
1761 L</populate> method.
1765 sub _normalize_populate_args {
1766 my ($self, $data) = @_;
1767 my @names = @{shift(@$data)};
1768 my @results_to_create;
1769 foreach my $datum (@$data) {
1770 my %result_to_create;
1771 foreach my $index (0..$#names) {
1772 $result_to_create{$names[$index]} = $$datum[$index];
1774 push @results_to_create, \%result_to_create;
1776 return \@results_to_create;
1783 =item Arguments: none
1785 =item Return Value: $pager
1789 Return Value a L<Data::Page> object for the current resultset. Only makes
1790 sense for queries with a C<page> attribute.
1792 To get the full count of entries for a paged resultset, call
1793 C<total_entries> on the L<Data::Page> object.
1800 return $self->{pager} if $self->{pager};
1802 my $attrs = $self->{attrs};
1803 $self->throw_exception("Can't create pager for non-paged rs")
1804 unless $self->{attrs}{page};
1805 $attrs->{rows} ||= 10;
1807 # throw away the paging flags and re-run the count (possibly
1808 # with a subselect) to get the real total count
1809 my $count_attrs = { %$attrs };
1810 delete $count_attrs->{$_} for qw/rows offset page pager/;
1811 my $total_count = (ref $self)->new($self->result_source, $count_attrs)->count;
1813 return $self->{pager} = Data::Page->new(
1816 $self->{attrs}{page}
1824 =item Arguments: $page_number
1826 =item Return Value: $rs
1830 Returns a resultset for the $page_number page of the resultset on which page
1831 is called, where each page contains a number of rows equal to the 'rows'
1832 attribute set on the resultset (10 by default).
1837 my ($self, $page) = @_;
1838 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1845 =item Arguments: \%vals
1847 =item Return Value: $rowobject
1851 Creates a new row object in the resultset's result class and returns
1852 it. The row is not inserted into the database at this point, call
1853 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
1854 will tell you whether the row object has been inserted or not.
1856 Passes the hashref of input on to L<DBIx::Class::Row/new>.
1861 my ($self, $values) = @_;
1862 $self->throw_exception( "new_result needs a hash" )
1863 unless (ref $values eq 'HASH');
1865 my ($merged_cond, $cols_from_relations) = $self->_merge_cond_with_data($values);
1869 @$cols_from_relations
1870 ? (-cols_from_relations => $cols_from_relations)
1872 -source_handle => $self->_source_handle,
1873 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
1876 return $self->result_class->new(\%new);
1879 # _merge_cond_with_data
1881 # Takes a simple hash of K/V data and returns its copy merged with the
1882 # condition already present on the resultset. Additionally returns an
1883 # arrayref of value/condition names, which were inferred from related
1884 # objects (this is needed for in-memory related objects)
1885 sub _merge_cond_with_data {
1886 my ($self, $data) = @_;
1888 my (%new_data, @cols_from_relations);
1890 my $alias = $self->{attrs}{alias};
1892 if (! defined $self->{cond}) {
1893 # just massage $data below
1895 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
1896 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
1897 @cols_from_relations = keys %new_data;
1899 elsif (ref $self->{cond} ne 'HASH') {
1900 $self->throw_exception(
1901 "Can't abstract implicit construct, resultset condition not a hash"
1905 # precendence must be given to passed values over values inherited from
1906 # the cond, so the order here is important.
1907 my $collapsed_cond = $self->_collapse_cond($self->{cond});
1908 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
1910 while ( my($col, $value) = each %implied ) {
1911 if (ref($value) eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '=') {
1912 $new_data{$col} = $value->{'='};
1915 $new_data{$col} = $value if $self->_is_deterministic_value($value);
1921 %{ $self->_remove_alias($data, $alias) },
1924 return (\%new_data, \@cols_from_relations);
1927 # _is_deterministic_value
1929 # Make an effor to strip non-deterministic values from the condition,
1930 # to make sure new_result chokes less
1932 sub _is_deterministic_value {
1935 my $ref_type = ref $value;
1936 return 1 if $ref_type eq '' || $ref_type eq 'SCALAR';
1937 return 1 if Scalar::Util::blessed($value);
1941 # _has_resolved_attr
1943 # determines if the resultset defines at least one
1944 # of the attributes supplied
1946 # used to determine if a subquery is neccessary
1948 # supports some virtual attributes:
1950 # This will scan for any joins being present on the resultset.
1951 # It is not a mere key-search but a deep inspection of {from}
1954 sub _has_resolved_attr {
1955 my ($self, @attr_names) = @_;
1957 my $attrs = $self->_resolved_attrs;
1961 for my $n (@attr_names) {
1962 if (grep { $n eq $_ } (qw/-join/) ) {
1963 $extra_checks{$n}++;
1967 my $attr = $attrs->{$n};
1969 next if not defined $attr;
1971 if (ref $attr eq 'HASH') {
1972 return 1 if keys %$attr;
1974 elsif (ref $attr eq 'ARRAY') {
1982 # a resolved join is expressed as a multi-level from
1984 $extra_checks{-join}
1986 ref $attrs->{from} eq 'ARRAY'
1988 @{$attrs->{from}} > 1
1996 # Recursively collapse the condition.
1998 sub _collapse_cond {
1999 my ($self, $cond, $collapsed) = @_;
2003 if (ref $cond eq 'ARRAY') {
2004 foreach my $subcond (@$cond) {
2005 next unless ref $subcond; # -or
2006 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2009 elsif (ref $cond eq 'HASH') {
2010 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2011 foreach my $subcond (@{$cond->{-and}}) {
2012 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2016 foreach my $col (keys %$cond) {
2017 my $value = $cond->{$col};
2018 $collapsed->{$col} = $value;
2028 # Remove the specified alias from the specified query hash. A copy is made so
2029 # the original query is not modified.
2032 my ($self, $query, $alias) = @_;
2034 my %orig = %{ $query || {} };
2037 foreach my $key (keys %orig) {
2039 $unaliased{$key} = $orig{$key};
2042 $unaliased{$1} = $orig{$key}
2043 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2049 =head2 as_query (EXPERIMENTAL)
2053 =item Arguments: none
2055 =item Return Value: \[ $sql, @bind ]
2059 Returns the SQL query and bind vars associated with the invocant.
2061 This is generally used as the RHS for a subquery.
2063 B<NOTE>: This feature is still experimental.
2070 my $attrs = $self->_resolved_attrs_copy;
2075 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2076 # $sql also has no wrapping parenthesis in list ctx
2078 my $sqlbind = $self->result_source->storage
2079 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2088 =item Arguments: \%vals, \%attrs?
2090 =item Return Value: $rowobject
2094 my $artist = $schema->resultset('Artist')->find_or_new(
2095 { artist => 'fred' }, { key => 'artists' });
2097 $cd->cd_to_producer->find_or_new({ producer => $producer },
2098 { key => 'primary });
2100 Find an existing record from this resultset, based on its primary
2101 key, or a unique constraint. If none exists, instantiate a new result
2102 object and return it. The object will not be saved into your storage
2103 until you call L<DBIx::Class::Row/insert> on it.
2105 You most likely want this method when looking for existing rows using
2106 a unique constraint that is not the primary key, or looking for
2109 If you want objects to be saved immediately, use L</find_or_create>
2112 B<Note>: Take care when using C<find_or_new> with a table having
2113 columns with default values that you intend to be automatically
2114 supplied by the database (e.g. an auto_increment primary key column).
2115 In normal usage, the value of such columns should NOT be included at
2116 all in the call to C<find_or_new>, even when set to C<undef>.
2122 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2123 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2124 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2127 return $self->new_result($hash);
2134 =item Arguments: \%vals
2136 =item Return Value: a L<DBIx::Class::Row> $object
2140 Attempt to create a single new row or a row with multiple related rows
2141 in the table represented by the resultset (and related tables). This
2142 will not check for duplicate rows before inserting, use
2143 L</find_or_create> to do that.
2145 To create one row for this resultset, pass a hashref of key/value
2146 pairs representing the columns of the table and the values you wish to
2147 store. If the appropriate relationships are set up, foreign key fields
2148 can also be passed an object representing the foreign row, and the
2149 value will be set to its primary key.
2151 To create related objects, pass a hashref of related-object column values
2152 B<keyed on the relationship name>. If the relationship is of type C<multi>
2153 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2154 The process will correctly identify columns holding foreign keys, and will
2155 transparrently populate them from the keys of the corresponding relation.
2156 This can be applied recursively, and will work correctly for a structure
2157 with an arbitrary depth and width, as long as the relationships actually
2158 exists and the correct column data has been supplied.
2161 Instead of hashrefs of plain related data (key/value pairs), you may
2162 also pass new or inserted objects. New objects (not inserted yet, see
2163 L</new>), will be inserted into their appropriate tables.
2165 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2167 Example of creating a new row.
2169 $person_rs->create({
2170 name=>"Some Person",
2171 email=>"somebody@someplace.com"
2174 Example of creating a new row and also creating rows in a related C<has_many>
2175 or C<has_one> resultset. Note Arrayref.
2178 { artistid => 4, name => 'Manufactured Crap', cds => [
2179 { title => 'My First CD', year => 2006 },
2180 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2185 Example of creating a new row and also creating a row in a related
2186 C<belongs_to>resultset. Note Hashref.
2189 title=>"Music for Silly Walks",
2192 name=>"Silly Musician",
2200 When subclassing ResultSet never attempt to override this method. Since
2201 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2202 lot of the internals simply never call it, so your override will be
2203 bypassed more often than not. Override either L<new|DBIx::Class::Row/new>
2204 or L<insert|DBIx::Class::Row/insert> depending on how early in the
2205 L</create> process you need to intervene.
2212 my ($self, $attrs) = @_;
2213 $self->throw_exception( "create needs a hashref" )
2214 unless ref $attrs eq 'HASH';
2215 return $self->new_result($attrs)->insert;
2218 =head2 find_or_create
2222 =item Arguments: \%vals, \%attrs?
2224 =item Return Value: $rowobject
2228 $cd->cd_to_producer->find_or_create({ producer => $producer },
2229 { key => 'primary' });
2231 Tries to find a record based on its primary key or unique constraints; if none
2232 is found, creates one and returns that instead.
2234 my $cd = $schema->resultset('CD')->find_or_create({
2236 artist => 'Massive Attack',
2237 title => 'Mezzanine',
2241 Also takes an optional C<key> attribute, to search by a specific key or unique
2242 constraint. For example:
2244 my $cd = $schema->resultset('CD')->find_or_create(
2246 artist => 'Massive Attack',
2247 title => 'Mezzanine',
2249 { key => 'cd_artist_title' }
2252 B<Note>: Because find_or_create() reads from the database and then
2253 possibly inserts based on the result, this method is subject to a race
2254 condition. Another process could create a record in the table after
2255 the find has completed and before the create has started. To avoid
2256 this problem, use find_or_create() inside a transaction.
2258 B<Note>: Take care when using C<find_or_create> with a table having
2259 columns with default values that you intend to be automatically
2260 supplied by the database (e.g. an auto_increment primary key column).
2261 In normal usage, the value of such columns should NOT be included at
2262 all in the call to C<find_or_create>, even when set to C<undef>.
2264 See also L</find> and L</update_or_create>. For information on how to declare
2265 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2269 sub find_or_create {
2271 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2272 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2273 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2276 return $self->create($hash);
2279 =head2 update_or_create
2283 =item Arguments: \%col_values, { key => $unique_constraint }?
2285 =item Return Value: $rowobject
2289 $resultset->update_or_create({ col => $val, ... });
2291 First, searches for an existing row matching one of the unique constraints
2292 (including the primary key) on the source of this resultset. If a row is
2293 found, updates it with the other given column values. Otherwise, creates a new
2296 Takes an optional C<key> attribute to search on a specific unique constraint.
2299 # In your application
2300 my $cd = $schema->resultset('CD')->update_or_create(
2302 artist => 'Massive Attack',
2303 title => 'Mezzanine',
2306 { key => 'cd_artist_title' }
2309 $cd->cd_to_producer->update_or_create({
2310 producer => $producer,
2317 If no C<key> is specified, it searches on all unique constraints defined on the
2318 source, including the primary key.
2320 If the C<key> is specified as C<primary>, it searches only on the primary key.
2322 See also L</find> and L</find_or_create>. For information on how to declare
2323 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2325 B<Note>: Take care when using C<update_or_create> with a table having
2326 columns with default values that you intend to be automatically
2327 supplied by the database (e.g. an auto_increment primary key column).
2328 In normal usage, the value of such columns should NOT be included at
2329 all in the call to C<update_or_create>, even when set to C<undef>.
2333 sub update_or_create {
2335 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2336 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2338 my $row = $self->find($cond, $attrs);
2340 $row->update($cond);
2344 return $self->create($cond);
2347 =head2 update_or_new
2351 =item Arguments: \%col_values, { key => $unique_constraint }?
2353 =item Return Value: $rowobject
2357 $resultset->update_or_new({ col => $val, ... });
2359 First, searches for an existing row matching one of the unique constraints
2360 (including the primary key) on the source of this resultset. If a row is
2361 found, updates it with the other given column values. Otherwise, instantiate
2362 a new result object and return it. The object will not be saved into your storage
2363 until you call L<DBIx::Class::Row/insert> on it.
2365 Takes an optional C<key> attribute to search on a specific unique constraint.
2368 # In your application
2369 my $cd = $schema->resultset('CD')->update_or_new(
2371 artist => 'Massive Attack',
2372 title => 'Mezzanine',
2375 { key => 'cd_artist_title' }
2378 if ($cd->in_storage) {
2379 # the cd was updated
2382 # the cd is not yet in the database, let's insert it
2386 B<Note>: Take care when using C<update_or_new> with a table having
2387 columns with default values that you intend to be automatically
2388 supplied by the database (e.g. an auto_increment primary key column).
2389 In normal usage, the value of such columns should NOT be included at
2390 all in the call to C<update_or_new>, even when set to C<undef>.
2392 See also L</find>, L</find_or_create> and L</find_or_new>.
2398 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2399 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2401 my $row = $self->find( $cond, $attrs );
2402 if ( defined $row ) {
2403 $row->update($cond);
2407 return $self->new_result($cond);
2414 =item Arguments: none
2416 =item Return Value: \@cache_objects?
2420 Gets the contents of the cache for the resultset, if the cache is set.
2422 The cache is populated either by using the L</prefetch> attribute to
2423 L</search> or by calling L</set_cache>.
2435 =item Arguments: \@cache_objects
2437 =item Return Value: \@cache_objects
2441 Sets the contents of the cache for the resultset. Expects an arrayref
2442 of objects of the same class as those produced by the resultset. Note that
2443 if the cache is set the resultset will return the cached objects rather
2444 than re-querying the database even if the cache attr is not set.
2446 The contents of the cache can also be populated by using the
2447 L</prefetch> attribute to L</search>.
2452 my ( $self, $data ) = @_;
2453 $self->throw_exception("set_cache requires an arrayref")
2454 if defined($data) && (ref $data ne 'ARRAY');
2455 $self->{all_cache} = $data;
2462 =item Arguments: none
2464 =item Return Value: []
2468 Clears the cache for the resultset.
2473 shift->set_cache(undef);
2480 =item Arguments: none
2482 =item Return Value: true, if the resultset has been paginated
2490 return !!$self->{attrs}{page};
2493 =head2 related_resultset
2497 =item Arguments: $relationship_name
2499 =item Return Value: $resultset
2503 Returns a related resultset for the supplied relationship name.
2505 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2509 sub related_resultset {
2510 my ($self, $rel) = @_;
2512 $self->{related_resultsets} ||= {};
2513 return $self->{related_resultsets}{$rel} ||= do {
2514 my $rel_info = $self->result_source->relationship_info($rel);
2516 $self->throw_exception(
2517 "search_related: result source '" . $self->result_source->source_name .
2518 "' has no such relationship $rel")
2521 my $attrs = $self->_chain_relationship($rel);
2523 my $join_count = $attrs->{seen_join}{$rel};
2524 my $alias = ($join_count > 1 ? join('_', $rel, $join_count) : $rel);
2526 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2527 delete @{$attrs}{qw(result_class alias)};
2531 if (my $cache = $self->get_cache) {
2532 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2533 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
2538 my $rel_source = $self->result_source->related_source($rel);
2542 # The reason we do this now instead of passing the alias to the
2543 # search_rs below is that if you wrap/overload resultset on the
2544 # source you need to know what alias it's -going- to have for things
2545 # to work sanely (e.g. RestrictWithObject wants to be able to add
2546 # extra query restrictions, and these may need to be $alias.)
2548 my $rel_attrs = $rel_source->resultset_attributes;
2549 local $rel_attrs->{alias} = $alias;
2551 $rel_source->resultset
2555 where => $attrs->{where},
2558 $new->set_cache($new_cache) if $new_cache;
2563 =head2 current_source_alias
2567 =item Arguments: none
2569 =item Return Value: $source_alias
2573 Returns the current table alias for the result source this resultset is built
2574 on, that will be used in the SQL query. Usually it is C<me>.
2576 Currently the source alias that refers to the result set returned by a
2577 L</search>/L</find> family method depends on how you got to the resultset: it's
2578 C<me> by default, but eg. L</search_related> aliases it to the related result
2579 source name (and keeps C<me> referring to the original result set). The long
2580 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
2581 (and make this method unnecessary).
2583 Thus it's currently necessary to use this method in predefined queries (see
2584 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
2585 source alias of the current result set:
2587 # in a result set class
2589 my ($self, $user) = @_;
2591 my $me = $self->current_source_alias;
2593 return $self->search(
2594 "$me.modified" => $user->id,
2600 sub current_source_alias {
2603 return ($self->{attrs} || {})->{alias} || 'me';
2606 # This code is called by search_related, and makes sure there
2607 # is clear separation between the joins before, during, and
2608 # after the relationship. This information is needed later
2609 # in order to properly resolve prefetch aliases (any alias
2610 # with a relation_chain_depth less than the depth of the
2611 # current prefetch is not considered)
2613 # The increments happen twice per join. An even number means a
2614 # relationship specified via a search_related, whereas an odd
2615 # number indicates a join/prefetch added via attributes
2617 # Also this code will wrap the current resultset (the one we
2618 # chain to) in a subselect IFF it contains limiting attributes
2619 sub _chain_relationship {
2620 my ($self, $rel) = @_;
2621 my $source = $self->result_source;
2622 my $attrs = { %{$self->{attrs}||{}} };
2624 # we need to take the prefetch the attrs into account before we
2625 # ->_resolve_join as otherwise they get lost - captainL
2626 my $join = $self->_merge_attr( $attrs->{join}, $attrs->{prefetch} );
2628 delete @{$attrs}{qw/join prefetch collapse select as columns +select +as +columns/};
2630 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
2633 my @force_subq_attrs = qw/offset rows group_by having/;
2636 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
2638 $self->_has_resolved_attr (@force_subq_attrs)
2641 -source_handle => $source->handle,
2642 -alias => $attrs->{alias},
2643 $attrs->{alias} => $self->as_query,
2645 delete @{$attrs}{@force_subq_attrs, 'where'};
2646 $seen->{-relation_chain_depth} = 0;
2648 elsif ($attrs->{from}) { #shallow copy suffices
2649 $from = [ @{$attrs->{from}} ];
2653 -source_handle => $source->handle,
2654 -alias => $attrs->{alias},
2655 $attrs->{alias} => $source->from,
2659 my $jpath = ($seen->{-relation_chain_depth})
2660 ? $from->[-1][0]{-join_path}
2663 my @requested_joins = $source->_resolve_join(
2670 push @$from, @requested_joins;
2672 $seen->{-relation_chain_depth}++;
2674 # if $self already had a join/prefetch specified on it, the requested
2675 # $rel might very well be already included. What we do in this case
2676 # is effectively a no-op (except that we bump up the chain_depth on
2677 # the join in question so we could tell it *is* the search_related)
2681 # we consider the last one thus reverse
2682 for my $j (reverse @requested_joins) {
2683 if ($rel eq $j->[0]{-join_path}[-1]) {
2684 $j->[0]{-relation_chain_depth}++;
2690 # alternative way to scan the entire chain - not backwards compatible
2691 # for my $j (reverse @$from) {
2692 # next unless ref $j eq 'ARRAY';
2693 # if ($j->[0]{-join_path} && $j->[0]{-join_path}[-1] eq $rel) {
2694 # $j->[0]{-relation_chain_depth}++;
2695 # $already_joined++;
2700 unless ($already_joined) {
2701 push @$from, $source->_resolve_join(
2709 $seen->{-relation_chain_depth}++;
2711 return {%$attrs, from => $from, seen_join => $seen};
2714 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
2715 sub _resolved_attrs_copy {
2717 return { %{$self->_resolved_attrs (@_)} };
2720 sub _resolved_attrs {
2722 return $self->{_attrs} if $self->{_attrs};
2724 my $attrs = { %{ $self->{attrs} || {} } };
2725 my $source = $self->result_source;
2726 my $alias = $attrs->{alias};
2728 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
2731 # build columns (as long as select isn't set) into a set of as/select hashes
2732 unless ( $attrs->{select} ) {
2734 my @cols = ( ref($attrs->{columns}) eq 'ARRAY' )
2735 ? @{ delete $attrs->{columns}}
2737 ( delete $attrs->{columns} )
2744 ( ref($_) eq 'HASH' )
2748 /^\Q${alias}.\E(.+)$/
2762 # add the additional columns on
2763 foreach ( 'include_columns', '+columns' ) {
2764 push @colbits, map {
2765 ( ref($_) eq 'HASH' )
2767 : { ( split( /\./, $_ ) )[-1] => ( /\./ ? $_ : "${alias}.$_" ) }
2768 } ( ref($attrs->{$_}) eq 'ARRAY' ) ? @{ delete $attrs->{$_} } : delete $attrs->{$_} if ( $attrs->{$_} );
2771 # start with initial select items
2772 if ( $attrs->{select} ) {
2774 ( ref $attrs->{select} eq 'ARRAY' )
2775 ? [ @{ $attrs->{select} } ]
2776 : [ $attrs->{select} ];
2780 ref $attrs->{as} eq 'ARRAY'
2781 ? [ @{ $attrs->{as} } ]
2784 : [ map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{ $attrs->{select} } ]
2789 # otherwise we intialise select & as to empty
2790 $attrs->{select} = [];
2794 # now add colbits to select/as
2795 push( @{ $attrs->{select} }, map { values( %{$_} ) } @colbits );
2796 push( @{ $attrs->{as} }, map { keys( %{$_} ) } @colbits );
2799 if ( $adds = delete $attrs->{'+select'} ) {
2800 $adds = [$adds] unless ref $adds eq 'ARRAY';
2802 @{ $attrs->{select} },
2803 map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds
2806 if ( $adds = delete $attrs->{'+as'} ) {
2807 $adds = [$adds] unless ref $adds eq 'ARRAY';
2808 push( @{ $attrs->{as} }, @$adds );
2811 $attrs->{from} ||= [ {
2812 -source_handle => $source->handle,
2813 -alias => $self->{attrs}{alias},
2814 $self->{attrs}{alias} => $source->from,
2817 if ( $attrs->{join} || $attrs->{prefetch} ) {
2819 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
2820 if ref $attrs->{from} ne 'ARRAY';
2822 my $join = delete $attrs->{join} || {};
2824 if ( defined $attrs->{prefetch} ) {
2825 $join = $self->_merge_attr( $join, $attrs->{prefetch} );
2828 $attrs->{from} = # have to copy here to avoid corrupting the original
2830 @{ $attrs->{from} },
2831 $source->_resolve_join(
2834 { %{ $attrs->{seen_join} || {} } },
2835 ($attrs->{seen_join} && keys %{$attrs->{seen_join}})
2836 ? $attrs->{from}[-1][0]{-join_path}
2843 if ( defined $attrs->{order_by} ) {
2844 $attrs->{order_by} = (
2845 ref( $attrs->{order_by} ) eq 'ARRAY'
2846 ? [ @{ $attrs->{order_by} } ]
2847 : [ $attrs->{order_by} || () ]
2851 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
2852 $attrs->{group_by} = [ $attrs->{group_by} ];
2855 # generate the distinct induced group_by early, as prefetch will be carried via a
2856 # subquery (since a group_by is present)
2857 if (delete $attrs->{distinct}) {
2858 if ($attrs->{group_by}) {
2859 carp ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
2862 $attrs->{group_by} = [ grep { !ref($_) || (ref($_) ne 'HASH') } @{$attrs->{select}} ];
2864 # add any order_by parts that are not already present in the group_by
2865 # we need to be careful not to add any named functions/aggregates
2866 # i.e. select => [ ... { count => 'foo', -as 'foocount' } ... ]
2867 my %already_grouped = map { $_ => 1 } (@{$attrs->{group_by}});
2869 my $storage = $self->result_source->schema->storage;
2870 my $rs_column_list = $storage->_resolve_column_info ($attrs->{from});
2871 my @chunks = $storage->sql_maker->_order_by_chunks ($attrs->{order_by});
2873 for my $chunk (map { ref $_ ? @$_ : $_ } (@chunks) ) {
2874 $chunk =~ s/\s+ (?: ASC|DESC ) \s* $//ix;
2875 if ($rs_column_list->{$chunk} && not $already_grouped{$chunk}++) {
2876 push @{$attrs->{group_by}}, $chunk;
2882 $attrs->{collapse} ||= {};
2883 if ( my $prefetch = delete $attrs->{prefetch} ) {
2884 $prefetch = $self->_merge_attr( {}, $prefetch );
2886 my $prefetch_ordering = [];
2888 my $join_map = $self->_joinpath_aliases ($attrs->{from}, $attrs->{seen_join});
2891 $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
2893 # we need to somehow mark which columns came from prefetch
2894 $attrs->{_prefetch_select} = [ map { $_->[0] } @prefetch ];
2896 push @{ $attrs->{select} }, @{$attrs->{_prefetch_select}};
2897 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
2899 push( @{$attrs->{order_by}}, @$prefetch_ordering );
2900 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
2903 # if both page and offset are specified, produce a combined offset
2904 # even though it doesn't make much sense, this is what pre 081xx has
2906 if (my $page = delete $attrs->{page}) {
2908 ($attrs->{rows} * ($page - 1))
2910 ($attrs->{offset} || 0)
2914 return $self->{_attrs} = $attrs;
2917 sub _joinpath_aliases {
2918 my ($self, $fromspec, $seen) = @_;
2921 return $paths unless ref $fromspec eq 'ARRAY';
2923 my $cur_depth = $seen->{-relation_chain_depth} || 0;
2925 if ($cur_depth % 2) {
2926 $self->throw_exception ("-relation_chain_depth is not even, something went horribly wrong ($cur_depth)");
2929 for my $j (@$fromspec) {
2931 next if ref $j ne 'ARRAY';
2932 next if ($j->[0]{-relation_chain_depth} || 0) < $cur_depth;
2934 my $jpath = $j->[0]{-join_path};
2937 $p = $p->{$_} ||= {} for @{$jpath}[$cur_depth/2 .. $#$jpath]; #only even depths are actual jpath boundaries
2938 push @{$p->{-join_aliases} }, $j->[0]{-alias};
2945 my ($self, $attr) = @_;
2947 if (ref $attr eq 'HASH') {
2948 return $self->_rollout_hash($attr);
2949 } elsif (ref $attr eq 'ARRAY') {
2950 return $self->_rollout_array($attr);
2956 sub _rollout_array {
2957 my ($self, $attr) = @_;
2960 foreach my $element (@{$attr}) {
2961 if (ref $element eq 'HASH') {
2962 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
2963 } elsif (ref $element eq 'ARRAY') {
2964 # XXX - should probably recurse here
2965 push( @rolled_array, @{$self->_rollout_array($element)} );
2967 push( @rolled_array, $element );
2970 return \@rolled_array;
2974 my ($self, $attr) = @_;
2977 foreach my $key (keys %{$attr}) {
2978 push( @rolled_array, { $key => $attr->{$key} } );
2980 return \@rolled_array;
2983 sub _calculate_score {
2984 my ($self, $a, $b) = @_;
2986 if (defined $a xor defined $b) {
2989 elsif (not defined $a) {
2993 if (ref $b eq 'HASH') {
2994 my ($b_key) = keys %{$b};
2995 if (ref $a eq 'HASH') {
2996 my ($a_key) = keys %{$a};
2997 if ($a_key eq $b_key) {
2998 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3003 return ($a eq $b_key) ? 1 : 0;
3006 if (ref $a eq 'HASH') {
3007 my ($a_key) = keys %{$a};
3008 return ($b eq $a_key) ? 1 : 0;
3010 return ($b eq $a) ? 1 : 0;
3016 my ($self, $orig, $import) = @_;
3018 return $import unless defined($orig);
3019 return $orig unless defined($import);
3021 $orig = $self->_rollout_attr($orig);
3022 $import = $self->_rollout_attr($import);
3025 foreach my $import_element ( @{$import} ) {
3026 # find best candidate from $orig to merge $b_element into
3027 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3028 foreach my $orig_element ( @{$orig} ) {
3029 my $score = $self->_calculate_score( $orig_element, $import_element );
3030 if ($score > $best_candidate->{score}) {
3031 $best_candidate->{position} = $position;
3032 $best_candidate->{score} = $score;
3036 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3038 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3039 push( @{$orig}, $import_element );
3041 my $orig_best = $orig->[$best_candidate->{position}];
3042 # merge orig_best and b_element together and replace original with merged
3043 if (ref $orig_best ne 'HASH') {
3044 $orig->[$best_candidate->{position}] = $import_element;
3045 } elsif (ref $import_element eq 'HASH') {
3046 my ($key) = keys %{$orig_best};
3047 $orig->[$best_candidate->{position}] = { $key => $self->_merge_attr($orig_best->{$key}, $import_element->{$key}) };
3050 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3060 $self->_source_handle($_[0]->handle);
3062 $self->_source_handle->resolve;
3066 =head2 throw_exception
3068 See L<DBIx::Class::Schema/throw_exception> for details.
3072 sub throw_exception {
3075 if (ref $self && $self->_source_handle->schema) {
3076 $self->_source_handle->schema->throw_exception(@_)
3079 DBIx::Class::Exception->throw(@_);
3083 # XXX: FIXME: Attributes docs need clearing up
3087 Attributes are used to refine a ResultSet in various ways when
3088 searching for data. They can be passed to any method which takes an
3089 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3092 These are in no particular order:
3098 =item Value: ( $order_by | \@order_by | \%order_by )
3102 Which column(s) to order the results by.
3104 [The full list of suitable values is documented in
3105 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3108 If a single column name, or an arrayref of names is supplied, the
3109 argument is passed through directly to SQL. The hashref syntax allows
3110 for connection-agnostic specification of ordering direction:
3112 For descending order:
3114 order_by => { -desc => [qw/col1 col2 col3/] }
3116 For explicit ascending order:
3118 order_by => { -asc => 'col' }
3120 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3121 supported, although you are strongly encouraged to use the hashref
3122 syntax as outlined above.
3128 =item Value: \@columns
3132 Shortcut to request a particular set of columns to be retrieved. Each
3133 column spec may be a string (a table column name), or a hash (in which
3134 case the key is the C<as> value, and the value is used as the C<select>
3135 expression). Adds C<me.> onto the start of any column without a C<.> in
3136 it and sets C<select> from that, then auto-populates C<as> from
3137 C<select> as normal. (You may also use the C<cols> attribute, as in
3138 earlier versions of DBIC.)
3144 =item Value: \@columns
3148 Indicates additional columns to be selected from storage. Works the same
3149 as L</columns> but adds columns to the selection. (You may also use the
3150 C<include_columns> attribute, as in earlier versions of DBIC). For
3153 $schema->resultset('CD')->search(undef, {
3154 '+columns' => ['artist.name'],
3158 would return all CDs and include a 'name' column to the information
3159 passed to object inflation. Note that the 'artist' is the name of the
3160 column (or relationship) accessor, and 'name' is the name of the column
3161 accessor in the related table.
3163 =head2 include_columns
3167 =item Value: \@columns
3171 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3177 =item Value: \@select_columns
3181 Indicates which columns should be selected from the storage. You can use
3182 column names, or in the case of RDBMS back ends, function or stored procedure
3185 $rs = $schema->resultset('Employee')->search(undef, {
3188 { count => 'employeeid' },
3193 When you use function/stored procedure names and do not supply an C<as>
3194 attribute, the column names returned are storage-dependent. E.g. MySQL would
3195 return a column named C<count(employeeid)> in the above example.
3197 B<NOTE:> You will almost always need a corresponding 'as' entry when you use
3204 Indicates additional columns to be selected from storage. Works the same as
3205 L</select> but adds columns to the selection.
3213 Indicates additional column names for those added via L</+select>. See L</as>.
3221 =item Value: \@inflation_names
3225 Indicates column names for object inflation. That is, C<as>
3226 indicates the name that the column can be accessed as via the
3227 C<get_column> method (or via the object accessor, B<if one already
3228 exists>). It has nothing to do with the SQL code C<SELECT foo AS bar>.
3230 The C<as> attribute is used in conjunction with C<select>,
3231 usually when C<select> contains one or more function or stored
3234 $rs = $schema->resultset('Employee')->search(undef, {
3237 { count => 'employeeid' }
3239 as => ['name', 'employee_count'],
3242 my $employee = $rs->first(); # get the first Employee
3244 If the object against which the search is performed already has an accessor
3245 matching a column name specified in C<as>, the value can be retrieved using
3246 the accessor as normal:
3248 my $name = $employee->name();
3250 If on the other hand an accessor does not exist in the object, you need to
3251 use C<get_column> instead:
3253 my $employee_count = $employee->get_column('employee_count');
3255 You can create your own accessors if required - see
3256 L<DBIx::Class::Manual::Cookbook> for details.
3258 Please note: This will NOT insert an C<AS employee_count> into the SQL
3259 statement produced, it is used for internal access only. Thus
3260 attempting to use the accessor in an C<order_by> clause or similar
3261 will fail miserably.
3263 To get around this limitation, you can supply literal SQL to your
3264 C<select> attibute that contains the C<AS alias> text, eg:
3266 select => [\'myfield AS alias']
3272 =item Value: ($rel_name | \@rel_names | \%rel_names)
3276 Contains a list of relationships that should be joined for this query. For
3279 # Get CDs by Nine Inch Nails
3280 my $rs = $schema->resultset('CD')->search(
3281 { 'artist.name' => 'Nine Inch Nails' },
3282 { join => 'artist' }
3285 Can also contain a hash reference to refer to the other relation's relations.
3288 package MyApp::Schema::Track;
3289 use base qw/DBIx::Class/;
3290 __PACKAGE__->table('track');
3291 __PACKAGE__->add_columns(qw/trackid cd position title/);
3292 __PACKAGE__->set_primary_key('trackid');
3293 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3296 # In your application
3297 my $rs = $schema->resultset('Artist')->search(
3298 { 'track.title' => 'Teardrop' },
3300 join => { cd => 'track' },
3301 order_by => 'artist.name',
3305 You need to use the relationship (not the table) name in conditions,
3306 because they are aliased as such. The current table is aliased as "me", so
3307 you need to use me.column_name in order to avoid ambiguity. For example:
3309 # Get CDs from 1984 with a 'Foo' track
3310 my $rs = $schema->resultset('CD')->search(
3313 'tracks.name' => 'Foo'
3315 { join => 'tracks' }
3318 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3319 similarly for a third time). For e.g.
3321 my $rs = $schema->resultset('Artist')->search({
3322 'cds.title' => 'Down to Earth',
3323 'cds_2.title' => 'Popular',
3325 join => [ qw/cds cds/ ],
3328 will return a set of all artists that have both a cd with title 'Down
3329 to Earth' and a cd with title 'Popular'.
3331 If you want to fetch related objects from other tables as well, see C<prefetch>
3334 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3340 =item Value: ($rel_name | \@rel_names | \%rel_names)
3344 Contains one or more relationships that should be fetched along with
3345 the main query (when they are accessed afterwards the data will
3346 already be available, without extra queries to the database). This is
3347 useful for when you know you will need the related objects, because it
3348 saves at least one query:
3350 my $rs = $schema->resultset('Tag')->search(
3359 The initial search results in SQL like the following:
3361 SELECT tag.*, cd.*, artist.* FROM tag
3362 JOIN cd ON tag.cd = cd.cdid
3363 JOIN artist ON cd.artist = artist.artistid
3365 L<DBIx::Class> has no need to go back to the database when we access the
3366 C<cd> or C<artist> relationships, which saves us two SQL statements in this
3369 Simple prefetches will be joined automatically, so there is no need
3370 for a C<join> attribute in the above search.
3372 C<prefetch> can be used with the following relationship types: C<belongs_to>,
3373 C<has_one> (or if you're using C<add_relationship>, any relationship declared
3374 with an accessor type of 'single' or 'filter'). A more complex example that
3375 prefetches an artists cds, the tracks on those cds, and the tags associted
3376 with that artist is given below (assuming many-to-many from artists to tags):
3378 my $rs = $schema->resultset('Artist')->search(
3382 { cds => 'tracks' },
3383 { artist_tags => 'tags' }
3389 B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
3390 attributes will be ignored.
3392 B<CAVEATs>: Prefetch does a lot of deep magic. As such, it may not behave
3393 exactly as you might expect.
3399 Prefetch uses the L</cache> to populate the prefetched relationships. This
3400 may or may not be what you want.
3404 If you specify a condition on a prefetched relationship, ONLY those
3405 rows that match the prefetched condition will be fetched into that relationship.
3406 This means that adding prefetch to a search() B<may alter> what is returned by
3407 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
3409 my $artist_rs = $schema->resultset('Artist')->search({
3415 my $count = $artist_rs->first->cds->count;
3417 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
3419 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
3421 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
3423 that cmp_ok() may or may not pass depending on the datasets involved. This
3424 behavior may or may not survive the 0.09 transition.
3436 Makes the resultset paged and specifies the page to retrieve. Effectively
3437 identical to creating a non-pages resultset and then calling ->page($page)
3440 If L<rows> attribute is not specified it defaults to 10 rows per page.
3442 When you have a paged resultset, L</count> will only return the number
3443 of rows in the page. To get the total, use the L</pager> and call
3444 C<total_entries> on it.
3454 Specifes the maximum number of rows for direct retrieval or the number of
3455 rows per page if the page attribute or method is used.
3461 =item Value: $offset
3465 Specifies the (zero-based) row number for the first row to be returned, or the
3466 of the first row of the first page if paging is used.
3472 =item Value: \@columns
3476 A arrayref of columns to group by. Can include columns of joined tables.
3478 group_by => [qw/ column1 column2 ... /]
3484 =item Value: $condition
3488 HAVING is a select statement attribute that is applied between GROUP BY and
3489 ORDER BY. It is applied to the after the grouping calculations have been
3492 having => { 'count(employee)' => { '>=', 100 } }
3498 =item Value: (0 | 1)
3502 Set to 1 to group by all columns. If the resultset already has a group_by
3503 attribute, this setting is ignored and an appropriate warning is issued.
3509 Adds to the WHERE clause.
3511 # only return rows WHERE deleted IS NULL for all searches
3512 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
3514 Can be overridden by passing C<< { where => undef } >> as an attribute
3521 Set to 1 to cache search results. This prevents extra SQL queries if you
3522 revisit rows in your ResultSet:
3524 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
3526 while( my $artist = $resultset->next ) {
3530 $rs->first; # without cache, this would issue a query
3532 By default, searches are not cached.
3534 For more examples of using these attributes, see
3535 L<DBIx::Class::Manual::Cookbook>.
3541 =item Value: ( 'update' | 'shared' )
3545 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT