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 qw/blessed weaken/;
22 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class _source_handle/);
26 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
30 my $users_rs = $schema->resultset('User');
31 while( $user = $users_rs->next) {
32 print $user->username;
35 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
36 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
40 A ResultSet is an object which stores a set of conditions representing
41 a query. It is the backbone of DBIx::Class (i.e. the really
42 important/useful bit).
44 No SQL is executed on the database when a ResultSet is created, it
45 just stores all the conditions needed to create the query.
47 A basic ResultSet representing the data of an entire table is returned
48 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
49 L<Source|DBIx::Class::Manual::Glossary/Source> name.
51 my $users_rs = $schema->resultset('User');
53 A new ResultSet is returned from calling L</search> on an existing
54 ResultSet. The new one will contain all the conditions of the
55 original, plus any new conditions added in the C<search> call.
57 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
58 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
61 The query that the ResultSet represents is B<only> executed against
62 the database when these methods are called:
63 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
65 If a resultset is used in a numeric context it returns the L</count>.
66 However, if it is used in a boolean context it is B<always> true. So if
67 you want to check if a resultset has any results, you must use C<if $rs
72 =head2 Chaining resultsets
74 Let's say you've got a query that needs to be run to return some data
75 to the user. But, you have an authorization system in place that
76 prevents certain users from seeing certain information. So, you want
77 to construct the basic query in one method, but add constraints to it in
82 my $request = $self->get_request; # Get a request object somehow.
83 my $schema = $self->get_schema; # Get the DBIC schema object somehow.
85 my $cd_rs = $schema->resultset('CD')->search({
86 title => $request->param('title'),
87 year => $request->param('year'),
90 $self->apply_security_policy( $cd_rs );
95 sub apply_security_policy {
104 =head3 Resolving conditions and attributes
106 When a resultset is chained from another resultset, conditions and
107 attributes with the same keys need resolving.
109 L</join>, L</prefetch>, L</+select>, L</+as> attributes are merged
110 into the existing ones from the original resultset.
112 The L</where> and L</having> attributes, and any search conditions, are
113 merged with an SQL C<AND> to the existing condition from the original
116 All other attributes are overridden by any new ones supplied in the
119 =head2 Multiple queries
121 Since a resultset just defines a query, you can do all sorts of
122 things with it with the same object.
124 # Don't hit the DB yet.
125 my $cd_rs = $schema->resultset('CD')->search({
126 title => 'something',
130 # Each of these hits the DB individually.
131 my $count = $cd_rs->count;
132 my $most_recent = $cd_rs->get_column('date_released')->max();
133 my @records = $cd_rs->all;
135 And it's not just limited to SELECT statements.
141 $cd_rs->create({ artist => 'Fred' });
143 Which is the same as:
145 $schema->resultset('CD')->create({
146 title => 'something',
151 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
159 =item Arguments: $source, \%$attrs
161 =item Return Value: $rs
165 The resultset constructor. Takes a source object (usually a
166 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
167 L</ATTRIBUTES> below). Does not perform any queries -- these are
168 executed as needed by the other methods.
170 Generally you won't need to construct a resultset manually. You'll
171 automatically get one from e.g. a L</search> called in scalar context:
173 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
175 IMPORTANT: If called on an object, proxies to new_result instead so
177 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
179 will return a CD object, not a ResultSet.
185 return $class->new_result(@_) if ref $class;
187 my ($source, $attrs) = @_;
188 $source = $source->handle
189 unless $source->isa('DBIx::Class::ResultSourceHandle');
190 $attrs = { %{$attrs||{}} };
192 if ($attrs->{page}) {
193 $attrs->{rows} ||= 10;
196 $attrs->{alias} ||= 'me';
198 # Creation of {} and bless separated to mitigate RH perl bug
199 # see https://bugzilla.redhat.com/show_bug.cgi?id=196836
201 _source_handle => $source,
202 cond => $attrs->{where},
210 $attrs->{result_class} || $source->resolve->result_class
220 =item Arguments: $cond, \%attrs?
222 =item Return Value: $resultset (scalar context), @row_objs (list context)
226 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
227 my $new_rs = $cd_rs->search({ year => 2005 });
229 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
230 # year = 2005 OR year = 2004
232 If you need to pass in additional attributes but no additional condition,
233 call it as C<search(undef, \%attrs)>.
235 # "SELECT name, artistid FROM $artist_table"
236 my @all_artists = $schema->resultset('Artist')->search(undef, {
237 columns => [qw/name artistid/],
240 For a list of attributes that can be passed to C<search>, see
241 L</ATTRIBUTES>. For more examples of using this function, see
242 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
243 documentation for the first argument, see L<SQL::Abstract>.
245 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
251 my $rs = $self->search_rs( @_ );
252 return (wantarray ? $rs->all : $rs);
259 =item Arguments: $cond, \%attrs?
261 =item Return Value: $resultset
265 This method does the same exact thing as search() except it will
266 always return a resultset, even in list context.
273 # Special-case handling for (undef, undef).
274 if ( @_ == 2 && !defined $_[1] && !defined $_[0] ) {
279 $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
280 my $our_attrs = { %{$self->{attrs}} };
281 my $having = delete $our_attrs->{having};
282 my $where = delete $our_attrs->{where};
286 my %safe = (alias => 1, cache => 1);
289 (@_ && defined($_[0])) # @_ == () or (undef)
291 (keys %$attrs # empty attrs or only 'safe' attrs
292 && List::Util::first { !$safe{$_} } keys %$attrs)
294 # no search, effectively just a clone
295 $rows = $self->get_cache;
298 # reset the selector list
299 if (List::Util::first { exists $attrs->{$_} } qw{columns select as}) {
300 delete @{$our_attrs}{qw{select as columns +select +as +columns include_columns}};
303 my $new_attrs = { %{$our_attrs}, %{$attrs} };
305 # merge new attrs into inherited
306 foreach my $key (qw/join prefetch +select +as +columns include_columns bind/) {
307 next unless exists $attrs->{$key};
308 $new_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key});
313 (@_ == 1 || ref $_[0] eq "HASH")
315 (ref $_[0] eq 'HASH')
317 (keys %{ $_[0] } > 0)
325 ? $self->throw_exception("Odd number of arguments to search")
332 if (defined $where) {
333 $new_attrs->{where} = (
334 defined $new_attrs->{where}
337 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
338 } $where, $new_attrs->{where}
345 $new_attrs->{where} = (
346 defined $new_attrs->{where}
349 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
350 } $cond, $new_attrs->{where}
356 if (defined $having) {
357 $new_attrs->{having} = (
358 defined $new_attrs->{having}
361 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
362 } $having, $new_attrs->{having}
368 my $rs = (ref $self)->new($self->result_source, $new_attrs);
370 $rs->set_cache($rows) if ($rows);
375 =head2 search_literal
379 =item Arguments: $sql_fragment, @bind_values
381 =item Return Value: $resultset (scalar context), @row_objs (list context)
385 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
386 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
388 Pass a literal chunk of SQL to be added to the conditional part of the
391 CAVEAT: C<search_literal> is provided for Class::DBI compatibility and should
392 only be used in that context. C<search_literal> is a convenience method.
393 It is equivalent to calling $schema->search(\[]), but if you want to ensure
394 columns are bound correctly, use C<search>.
396 Example of how to use C<search> instead of C<search_literal>
398 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
399 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
402 See L<DBIx::Class::Manual::Cookbook/Searching> and
403 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
404 require C<search_literal>.
409 my ($self, $sql, @bind) = @_;
411 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
414 return $self->search(\[ $sql, map [ __DUMMY__ => $_ ], @bind ], ($attr || () ));
421 =item Arguments: @values | \%cols, \%attrs?
423 =item Return Value: $row_object | undef
427 Finds a row based on its primary key or unique constraint. For example, to find
428 a row by its primary key:
430 my $cd = $schema->resultset('CD')->find(5);
432 You can also find a row by a specific unique constraint using the C<key>
433 attribute. For example:
435 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
436 key => 'cd_artist_title'
439 Additionally, you can specify the columns explicitly by name:
441 my $cd = $schema->resultset('CD')->find(
443 artist => 'Massive Attack',
444 title => 'Mezzanine',
446 { key => 'cd_artist_title' }
449 If the C<key> is specified as C<primary>, it searches only on the primary key.
451 If no C<key> is specified, it searches on all unique constraints defined on the
452 source for which column data is provided, including the primary key.
454 If your table does not have a primary key, you B<must> provide a value for the
455 C<key> attribute matching one of the unique constraints on the source.
457 In addition to C<key>, L</find> recognizes and applies standard
458 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
460 Note: If your query does not return only one row, a warning is generated:
462 Query returned more than one row
464 See also L</find_or_create> and L</update_or_create>. For information on how to
465 declare unique constraints, see
466 L<DBIx::Class::ResultSource/add_unique_constraint>.
472 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
474 # Default to the primary key, but allow a specific key
475 my @cols = exists $attrs->{key}
476 ? $self->result_source->unique_constraint_columns($attrs->{key})
477 : $self->result_source->primary_columns;
478 $self->throw_exception(
479 "Can't find unless a primary key is defined or unique constraint is specified"
482 # Parse out a hashref from input
484 if (ref $_[0] eq 'HASH') {
485 $input_query = { %{$_[0]} };
487 elsif (@_ == @cols) {
489 @{$input_query}{@cols} = @_;
492 # Compatibility: Allow e.g. find(id => $value)
493 carp "Find by key => value deprecated; please use a hashref instead";
497 my (%related, $info);
499 KEY: foreach my $key (keys %$input_query) {
500 if (ref($input_query->{$key})
501 && ($info = $self->result_source->relationship_info($key))) {
502 my $val = delete $input_query->{$key};
503 next KEY if (ref($val) eq 'ARRAY'); # has_many for multi_create
504 my $rel_q = $self->result_source->_resolve_condition(
505 $info->{cond}, $val, $key
507 die "Can't handle OR join condition in find" if ref($rel_q) eq 'ARRAY';
508 @related{keys %$rel_q} = values %$rel_q;
511 if (my @keys = keys %related) {
512 @{$input_query}{@keys} = values %related;
516 # Build the final query: Default to the disjunction of the unique queries,
517 # but allow the input query in case the ResultSet defines the query or the
518 # user is abusing find
519 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
521 if (exists $attrs->{key}) {
522 my @unique_cols = $self->result_source->unique_constraint_columns($attrs->{key});
523 my $unique_query = $self->_build_unique_query($input_query, \@unique_cols);
524 $query = $self->_add_alias($unique_query, $alias);
526 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
527 # This means that we got here after a merger of relationship conditions
528 # in ::Relationship::Base::search_related (the row method), and furthermore
529 # the relationship is of the 'single' type. This means that the condition
530 # provided by the relationship (already attached to $self) is sufficient,
531 # as there can be only one row in the database that would satisfy the
535 my @unique_queries = $self->_unique_queries($input_query, $attrs);
536 $query = @unique_queries
537 ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
538 : $self->_add_alias($input_query, $alias);
541 # Run the query, passing the result_class since it should propagate for find
542 my $rs = $self->search ($query, {result_class => $self->result_class, %$attrs});
543 if (keys %{$rs->_resolved_attrs->{collapse}}) {
545 carp "Query returned more than one row" if $rs->next;
555 # Add the specified alias to the specified query hash. A copy is made so the
556 # original query is not modified.
559 my ($self, $query, $alias) = @_;
561 my %aliased = %$query;
562 foreach my $col (grep { ! m/\./ } keys %aliased) {
563 $aliased{"$alias.$col"} = delete $aliased{$col};
571 # Build a list of queries which satisfy unique constraints.
573 sub _unique_queries {
574 my ($self, $query, $attrs) = @_;
576 my @constraint_names = exists $attrs->{key}
578 : $self->result_source->unique_constraint_names;
580 my $where = $self->_collapse_cond($self->{attrs}{where} || {});
581 my $num_where = scalar keys %$where;
583 my (@unique_queries, %seen_column_combinations);
584 foreach my $name (@constraint_names) {
585 my @constraint_cols = $self->result_source->unique_constraint_columns($name);
587 my $constraint_sig = join "\x00", sort @constraint_cols;
588 next if $seen_column_combinations{$constraint_sig}++;
590 my $unique_query = $self->_build_unique_query($query, \@constraint_cols);
592 my $num_cols = scalar @constraint_cols;
593 my $num_query = scalar keys %$unique_query;
595 my $total = $num_query + $num_where;
596 if ($num_query && ($num_query == $num_cols || $total == $num_cols)) {
597 # The query is either unique on its own or is unique in combination with
598 # the existing where clause
599 push @unique_queries, $unique_query;
603 return @unique_queries;
606 # _build_unique_query
608 # Constrain the specified query hash based on the specified column names.
610 sub _build_unique_query {
611 my ($self, $query, $unique_cols) = @_;
614 map { $_ => $query->{$_} }
615 grep { exists $query->{$_} }
620 =head2 search_related
624 =item Arguments: $rel, $cond, \%attrs?
626 =item Return Value: $new_resultset
630 $new_rs = $cd_rs->search_related('artist', {
634 Searches the specified relationship, optionally specifying a condition and
635 attributes for matching records. See L</ATTRIBUTES> for more information.
640 return shift->related_resultset(shift)->search(@_);
643 =head2 search_related_rs
645 This method works exactly the same as search_related, except that
646 it guarantees a resultset, even in list context.
650 sub search_related_rs {
651 return shift->related_resultset(shift)->search_rs(@_);
658 =item Arguments: none
660 =item Return Value: $cursor
664 Returns a storage-driven cursor to the given resultset. See
665 L<DBIx::Class::Cursor> for more information.
672 my $attrs = $self->_resolved_attrs_copy;
674 return $self->{cursor}
675 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
676 $attrs->{where},$attrs);
683 =item Arguments: $cond?
685 =item Return Value: $row_object | undef
689 my $cd = $schema->resultset('CD')->single({ year => 2001 });
691 Inflates the first result without creating a cursor if the resultset has
692 any records in it; if not returns C<undef>. Used by L</find> as a lean version
695 While this method can take an optional search condition (just like L</search>)
696 being a fast-code-path it does not recognize search attributes. If you need to
697 add extra joins or similar, call L</search> and then chain-call L</single> on the
698 L<DBIx::Class::ResultSet> returned.
704 As of 0.08100, this method enforces the assumption that the preceding
705 query returns only one row. If more than one row is returned, you will receive
708 Query returned more than one row
710 In this case, you should be using L</next> or L</find> instead, or if you really
711 know what you are doing, use the L</rows> attribute to explicitly limit the size
714 This method will also throw an exception if it is called on a resultset prefetching
715 has_many, as such a prefetch implies fetching multiple rows from the database in
716 order to assemble the resulting object.
723 my ($self, $where) = @_;
725 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
728 my $attrs = $self->_resolved_attrs_copy;
730 if (keys %{$attrs->{collapse}}) {
731 $self->throw_exception(
732 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
737 if (defined $attrs->{where}) {
740 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
741 $where, delete $attrs->{where} ]
744 $attrs->{where} = $where;
748 # XXX: Disabled since it doesn't infer uniqueness in all cases
749 # unless ($self->_is_unique_query($attrs->{where})) {
750 # carp "Query not guaranteed to return a single row"
751 # . "; please declare your unique constraints or use search instead";
754 my @data = $self->result_source->storage->select_single(
755 $attrs->{from}, $attrs->{select},
756 $attrs->{where}, $attrs
759 return (@data ? ($self->_construct_object(@data))[0] : undef);
765 # Try to determine if the specified query is guaranteed to be unique, based on
766 # the declared unique constraints.
768 sub _is_unique_query {
769 my ($self, $query) = @_;
771 my $collapsed = $self->_collapse_query($query);
772 my $alias = $self->{attrs}{alias};
774 foreach my $name ($self->result_source->unique_constraint_names) {
775 my @unique_cols = map {
777 } $self->result_source->unique_constraint_columns($name);
779 # Count the values for each unique column
780 my %seen = map { $_ => 0 } @unique_cols;
782 foreach my $key (keys %$collapsed) {
783 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
784 next unless exists $seen{$aliased}; # Additional constraints are okay
785 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
788 # If we get 0 or more than 1 value for a column, it's not necessarily unique
789 return 1 unless grep { $_ != 1 } values %seen;
797 # Recursively collapse the query, accumulating values for each column.
799 sub _collapse_query {
800 my ($self, $query, $collapsed) = @_;
804 if (ref $query eq 'ARRAY') {
805 foreach my $subquery (@$query) {
806 next unless ref $subquery; # -or
807 $collapsed = $self->_collapse_query($subquery, $collapsed);
810 elsif (ref $query eq 'HASH') {
811 if (keys %$query and (keys %$query)[0] eq '-and') {
812 foreach my $subquery (@{$query->{-and}}) {
813 $collapsed = $self->_collapse_query($subquery, $collapsed);
817 foreach my $col (keys %$query) {
818 my $value = $query->{$col};
819 $collapsed->{$col}{$value}++;
831 =item Arguments: $cond?
833 =item Return Value: $resultsetcolumn
837 my $max_length = $rs->get_column('length')->max;
839 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
844 my ($self, $column) = @_;
845 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
853 =item Arguments: $cond, \%attrs?
855 =item Return Value: $resultset (scalar context), @row_objs (list context)
859 # WHERE title LIKE '%blue%'
860 $cd_rs = $rs->search_like({ title => '%blue%'});
862 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
863 that this is simply a convenience method retained for ex Class::DBI users.
864 You most likely want to use L</search> with specific operators.
866 For more information, see L<DBIx::Class::Manual::Cookbook>.
868 This method is deprecated and will be removed in 0.09. Use L</search()>
869 instead. An example conversion is:
871 ->search_like({ foo => 'bar' });
875 ->search({ foo => { like => 'bar' } });
882 'search_like() is deprecated and will be removed in DBIC version 0.09.'
883 .' Instead use ->search({ x => { -like => "y%" } })'
884 .' (note the outer pair of {}s - they are important!)'
886 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
887 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
888 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
889 return $class->search($query, { %$attrs });
896 =item Arguments: $first, $last
898 =item Return Value: $resultset (scalar context), @row_objs (list context)
902 Returns a resultset or object list representing a subset of elements from the
903 resultset slice is called on. Indexes are from 0, i.e., to get the first
906 my ($one, $two, $three) = $rs->slice(0, 2);
911 my ($self, $min, $max) = @_;
912 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
913 $attrs->{offset} = $self->{attrs}{offset} || 0;
914 $attrs->{offset} += $min;
915 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
916 return $self->search(undef, $attrs);
917 #my $slice = (ref $self)->new($self->result_source, $attrs);
918 #return (wantarray ? $slice->all : $slice);
925 =item Arguments: none
927 =item Return Value: $result | undef
931 Returns the next element in the resultset (C<undef> is there is none).
933 Can be used to efficiently iterate over records in the resultset:
935 my $rs = $schema->resultset('CD')->search;
936 while (my $cd = $rs->next) {
940 Note that you need to store the resultset object, and call C<next> on it.
941 Calling C<< resultset('Table')->next >> repeatedly will always return the
942 first record from the resultset.
948 if (my $cache = $self->get_cache) {
949 $self->{all_cache_position} ||= 0;
950 return $cache->[$self->{all_cache_position}++];
952 if ($self->{attrs}{cache}) {
953 delete $self->{pager};
954 $self->{all_cache_position} = 1;
955 return ($self->all)[0];
957 if ($self->{stashed_objects}) {
958 my $obj = shift(@{$self->{stashed_objects}});
959 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
963 exists $self->{stashed_row}
964 ? @{delete $self->{stashed_row}}
965 : $self->cursor->next
967 return undef unless (@row);
968 my ($row, @more) = $self->_construct_object(@row);
969 $self->{stashed_objects} = \@more if @more;
973 sub _construct_object {
974 my ($self, @row) = @_;
976 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row)
978 my @new = $self->result_class->inflate_result($self->result_source, @$info);
979 @new = $self->{_attrs}{record_filter}->(@new)
980 if exists $self->{_attrs}{record_filter};
984 sub _collapse_result {
985 my ($self, $as_proto, $row) = @_;
989 # 'foo' => [ undef, 'foo' ]
990 # 'foo.bar' => [ 'foo', 'bar' ]
991 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
993 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
995 my %collapse = %{$self->{_attrs}{collapse}||{}};
999 # if we're doing collapsing (has_many prefetch) we need to grab records
1000 # until the PK changes, so fill @pri_index. if not, we leave it empty so
1001 # we know we don't have to bother.
1003 # the reason for not using the collapse stuff directly is because if you
1004 # had for e.g. two artists in a row with no cds, the collapse info for
1005 # both would be NULL (undef) so you'd lose the second artist
1007 # store just the index so we can check the array positions from the row
1008 # without having to contruct the full hash
1010 if (keys %collapse) {
1011 my %pri = map { ($_ => 1) } $self->result_source->_pri_cols;
1012 foreach my $i (0 .. $#construct_as) {
1013 next if defined($construct_as[$i][0]); # only self table
1014 if (delete $pri{$construct_as[$i][1]}) {
1015 push(@pri_index, $i);
1017 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
1021 # no need to do an if, it'll be empty if @pri_index is empty anyway
1023 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
1027 do { # no need to check anything at the front, we always want the first row
1031 foreach my $this_as (@construct_as) {
1032 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
1035 push(@const_rows, \%const);
1037 } until ( # no pri_index => no collapse => drop straight out
1040 do { # get another row, stash it, drop out if different PK
1042 @copy = $self->cursor->next;
1043 $self->{stashed_row} = \@copy;
1045 # last thing in do block, counts as true if anything doesn't match
1047 # check xor defined first for NULL vs. NOT NULL then if one is
1048 # defined the other must be so check string equality
1051 (defined $pri_vals{$_} ^ defined $copy[$_])
1052 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
1057 my $alias = $self->{attrs}{alias};
1064 foreach my $const (@const_rows) {
1065 scalar @const_keys or do {
1066 @const_keys = sort { length($a) <=> length($b) } keys %$const;
1068 foreach my $key (@const_keys) {
1071 my @parts = split(/\./, $key);
1073 my $data = $const->{$key};
1074 foreach my $p (@parts) {
1075 $target = $target->[1]->{$p} ||= [];
1077 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
1078 # collapsing at this point and on final part
1079 my $pos = $collapse_pos{$cur};
1080 CK: foreach my $ck (@ckey) {
1081 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
1082 $collapse_pos{$cur} = $data;
1083 delete @collapse_pos{ # clear all positioning for sub-entries
1084 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
1091 if (exists $collapse{$cur}) {
1092 $target = $target->[-1];
1095 $target->[0] = $data;
1097 $info->[0] = $const->{$key};
1105 =head2 result_source
1109 =item Arguments: $result_source?
1111 =item Return Value: $result_source
1115 An accessor for the primary ResultSource object from which this ResultSet
1122 =item Arguments: $result_class?
1124 =item Return Value: $result_class
1128 An accessor for the class to use when creating row objects. Defaults to
1129 C<< result_source->result_class >> - which in most cases is the name of the
1130 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1132 Note that changing the result_class will also remove any components
1133 that were originally loaded in the source class via
1134 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1135 in the original source class will not run.
1140 my ($self, $result_class) = @_;
1141 if ($result_class) {
1142 unless (ref $result_class) { # don't fire this for an object
1143 $self->ensure_class_loaded($result_class);
1145 $self->_result_class($result_class);
1146 # THIS LINE WOULD BE A BUG - this accessor specifically exists to
1147 # permit the user to set result class on one result set only; it only
1148 # chains if provided to search()
1149 #$self->{attrs}{result_class} = $result_class if ref $self;
1151 $self->_result_class;
1158 =item Arguments: $cond, \%attrs??
1160 =item Return Value: $count
1164 Performs an SQL C<COUNT> with the same query as the resultset was built
1165 with to find the number of elements. Passing arguments is equivalent to
1166 C<< $rs->search ($cond, \%attrs)->count >>
1172 return $self->search(@_)->count if @_ and defined $_[0];
1173 return scalar @{ $self->get_cache } if $self->get_cache;
1175 my $attrs = $self->_resolved_attrs_copy;
1177 # this is a little optimization - it is faster to do the limit
1178 # adjustments in software, instead of a subquery
1179 my $rows = delete $attrs->{rows};
1180 my $offset = delete $attrs->{offset};
1183 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1184 $crs = $self->_count_subq_rs ($attrs);
1187 $crs = $self->_count_rs ($attrs);
1189 my $count = $crs->next;
1191 $count -= $offset if $offset;
1192 $count = $rows if $rows and $rows < $count;
1193 $count = 0 if ($count < 0);
1202 =item Arguments: $cond, \%attrs??
1204 =item Return Value: $count_rs
1208 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1209 This can be very handy for subqueries:
1211 ->search( { amount => $some_rs->count_rs->as_query } )
1213 As with regular resultsets the SQL query will be executed only after
1214 the resultset is accessed via L</next> or L</all>. That would return
1215 the same single value obtainable via L</count>.
1221 return $self->search(@_)->count_rs if @_;
1223 # this may look like a lack of abstraction (count() does about the same)
1224 # but in fact an _rs *must* use a subquery for the limits, as the
1225 # software based limiting can not be ported if this $rs is to be used
1226 # in a subquery itself (i.e. ->as_query)
1227 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1228 return $self->_count_subq_rs;
1231 return $self->_count_rs;
1236 # returns a ResultSetColumn object tied to the count query
1239 my ($self, $attrs) = @_;
1241 my $rsrc = $self->result_source;
1242 $attrs ||= $self->_resolved_attrs;
1244 my $tmp_attrs = { %$attrs };
1245 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1246 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1248 # overwrite the selector (supplied by the storage)
1249 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $attrs);
1250 $tmp_attrs->{as} = 'count';
1252 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1258 # same as above but uses a subquery
1260 sub _count_subq_rs {
1261 my ($self, $attrs) = @_;
1263 my $rsrc = $self->result_source;
1264 $attrs ||= $self->_resolved_attrs;
1266 my $sub_attrs = { %$attrs };
1267 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1268 delete @{$sub_attrs}{qw/collapse select _prefetch_select as order_by for/};
1270 # if we multi-prefetch we group_by primary keys only as this is what we would
1271 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1272 if ( keys %{$attrs->{collapse}} ) {
1273 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } ($rsrc->_pri_cols) ]
1276 # Calculate subquery selector
1277 if (my $g = $sub_attrs->{group_by}) {
1279 my $sql_maker = $rsrc->storage->sql_maker;
1281 # necessary as the group_by may refer to aliased functions
1283 for my $sel (@{$attrs->{select}}) {
1284 $sel_index->{$sel->{-as}} = $sel
1285 if (ref $sel eq 'HASH' and $sel->{-as});
1288 for my $g_part (@$g) {
1289 my $colpiece = $sel_index->{$g_part} || $g_part;
1291 # disqualify join-based group_by's. Arcane but possible query
1292 # also horrible horrible hack to alias a column (not a func.)
1293 # (probably need to introduce SQLA syntax)
1294 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1297 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1299 push @{$sub_attrs->{select}}, $colpiece;
1303 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1304 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1307 return $rsrc->resultset_class
1308 ->new ($rsrc, $sub_attrs)
1310 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1311 ->get_column ('count');
1318 =head2 count_literal
1322 =item Arguments: $sql_fragment, @bind_values
1324 =item Return Value: $count
1328 Counts the results in a literal query. Equivalent to calling L</search_literal>
1329 with the passed arguments, then L</count>.
1333 sub count_literal { shift->search_literal(@_)->count; }
1339 =item Arguments: none
1341 =item Return Value: @objects
1345 Returns all elements in the resultset. Called implicitly if the resultset
1346 is returned in list context.
1353 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1356 return @{ $self->get_cache } if $self->get_cache;
1360 if (keys %{$self->_resolved_attrs->{collapse}}) {
1361 # Using $self->cursor->all is really just an optimisation.
1362 # If we're collapsing has_many prefetches it probably makes
1363 # very little difference, and this is cleaner than hacking
1364 # _construct_object to survive the approach
1365 $self->cursor->reset;
1366 my @row = $self->cursor->next;
1368 push(@obj, $self->_construct_object(@row));
1369 @row = (exists $self->{stashed_row}
1370 ? @{delete $self->{stashed_row}}
1371 : $self->cursor->next);
1374 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1377 $self->set_cache(\@obj) if $self->{attrs}{cache};
1386 =item Arguments: none
1388 =item Return Value: $self
1392 Resets the resultset's cursor, so you can iterate through the elements again.
1393 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1400 delete $self->{_attrs} if exists $self->{_attrs};
1401 $self->{all_cache_position} = 0;
1402 $self->cursor->reset;
1410 =item Arguments: none
1412 =item Return Value: $object | undef
1416 Resets the resultset and returns an object for the first result (or C<undef>
1417 if the resultset is empty).
1422 return $_[0]->reset->next;
1428 # Determines whether and what type of subquery is required for the $rs operation.
1429 # If grouping is necessary either supplies its own, or verifies the current one
1430 # After all is done delegates to the proper storage method.
1432 sub _rs_update_delete {
1433 my ($self, $op, $values) = @_;
1435 my $rsrc = $self->result_source;
1437 # if a condition exists we need to strip all table qualifiers
1438 # if this is not possible we'll force a subquery below
1439 my $cond = $rsrc->schema->storage->_strip_cond_qualifiers ($self->{cond});
1441 my $needs_group_by_subq = $self->_has_resolved_attr (qw/collapse group_by -join/);
1442 my $needs_subq = $needs_group_by_subq || (not defined $cond) || $self->_has_resolved_attr(qw/rows offset/);
1444 if ($needs_group_by_subq or $needs_subq) {
1446 # make a new $rs selecting only the PKs (that's all we really need)
1447 my $attrs = $self->_resolved_attrs_copy;
1450 delete $attrs->{$_} for qw/collapse _collapse_order_by select _prefetch_select as/;
1451 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->_pri_cols) ];
1453 if ($needs_group_by_subq) {
1454 # make sure no group_by was supplied, or if there is one - make sure it matches
1455 # the columns compiled above perfectly. Anything else can not be sanely executed
1456 # on most databases so croak right then and there
1458 if (my $g = $attrs->{group_by}) {
1459 my @current_group_by = map
1460 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1465 join ("\x00", sort @current_group_by)
1467 join ("\x00", sort @{$attrs->{columns}} )
1469 $self->throw_exception (
1470 "You have just attempted a $op operation on a resultset which does group_by"
1471 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1472 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1473 . ' kind of queries. Please retry the operation with a modified group_by or'
1474 . ' without using one at all.'
1479 $attrs->{group_by} = $attrs->{columns};
1483 my $subrs = (ref $self)->new($rsrc, $attrs);
1484 return $self->result_source->storage->_subq_update_delete($subrs, $op, $values);
1487 return $rsrc->storage->$op(
1489 $op eq 'update' ? $values : (),
1499 =item Arguments: \%values
1501 =item Return Value: $storage_rv
1505 Sets the specified columns in the resultset to the supplied values in a
1506 single query. Return value will be true if the update succeeded or false
1507 if no records were updated; exact type of success value is storage-dependent.
1512 my ($self, $values) = @_;
1513 $self->throw_exception('Values for update must be a hash')
1514 unless ref $values eq 'HASH';
1516 return $self->_rs_update_delete ('update', $values);
1523 =item Arguments: \%values
1525 =item Return Value: 1
1529 Fetches all objects and updates them one at a time. Note that C<update_all>
1530 will run DBIC cascade triggers, while L</update> will not.
1535 my ($self, $values) = @_;
1536 $self->throw_exception('Values for update_all must be a hash')
1537 unless ref $values eq 'HASH';
1539 my $guard = $self->result_source->schema->txn_scope_guard;
1540 $_->update($values) for $self->all;
1549 =item Arguments: none
1551 =item Return Value: $storage_rv
1555 Deletes the contents of the resultset from its result source. Note that this
1556 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1557 to run. See also L<DBIx::Class::Row/delete>.
1559 Return value will be the number of rows deleted; exact type of return value
1560 is storage-dependent.
1566 $self->throw_exception('delete does not accept any arguments')
1569 return $self->_rs_update_delete ('delete');
1576 =item Arguments: none
1578 =item Return Value: 1
1582 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1583 will run DBIC cascade triggers, while L</delete> will not.
1589 $self->throw_exception('delete_all does not accept any arguments')
1592 my $guard = $self->result_source->schema->txn_scope_guard;
1593 $_->delete for $self->all;
1602 =item Arguments: \@data;
1606 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1607 For the arrayref of hashrefs style each hashref should be a structure suitable
1608 forsubmitting to a $resultset->create(...) method.
1610 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1611 to insert the data, as this is a faster method.
1613 Otherwise, each set of data is inserted into the database using
1614 L<DBIx::Class::ResultSet/create>, and the resulting objects are
1615 accumulated into an array. The array itself, or an array reference
1616 is returned depending on scalar or list context.
1618 Example: Assuming an Artist Class that has many CDs Classes relating:
1620 my $Artist_rs = $schema->resultset("Artist");
1622 ## Void Context Example
1623 $Artist_rs->populate([
1624 { artistid => 4, name => 'Manufactured Crap', cds => [
1625 { title => 'My First CD', year => 2006 },
1626 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1629 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1630 { title => 'My parents sold me to a record company', year => 2005 },
1631 { title => 'Why Am I So Ugly?', year => 2006 },
1632 { title => 'I Got Surgery and am now Popular', year => 2007 }
1637 ## Array Context Example
1638 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1639 { name => "Artist One"},
1640 { name => "Artist Two"},
1641 { name => "Artist Three", cds=> [
1642 { title => "First CD", year => 2007},
1643 { title => "Second CD", year => 2008},
1647 print $ArtistOne->name; ## response is 'Artist One'
1648 print $ArtistThree->cds->count ## reponse is '2'
1650 For the arrayref of arrayrefs style, the first element should be a list of the
1651 fieldsnames to which the remaining elements are rows being inserted. For
1654 $Arstist_rs->populate([
1655 [qw/artistid name/],
1656 [100, 'A Formally Unknown Singer'],
1657 [101, 'A singer that jumped the shark two albums ago'],
1658 [102, 'An actually cool singer'],
1661 Please note an important effect on your data when choosing between void and
1662 wantarray context. Since void context goes straight to C<insert_bulk> in
1663 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
1664 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
1665 create primary keys for you, you will find that your PKs are empty. In this
1666 case you will have to use the wantarray context in order to create those
1674 # cruft placed in standalone method
1675 my $data = $self->_normalize_populate_args(@_);
1677 if(defined wantarray) {
1679 foreach my $item (@$data) {
1680 push(@created, $self->create($item));
1682 return wantarray ? @created : \@created;
1684 my $first = $data->[0];
1686 # if a column is a registered relationship, and is a non-blessed hash/array, consider
1687 # it relationship data
1688 my (@rels, @columns);
1689 for (keys %$first) {
1690 my $ref = ref $first->{$_};
1691 $self->result_source->has_relationship($_) && ($ref eq 'ARRAY' or $ref eq 'HASH')
1697 my @pks = $self->result_source->primary_columns;
1699 ## do the belongs_to relationships
1700 foreach my $index (0..$#$data) {
1702 # delegate to create() for any dataset without primary keys with specified relationships
1703 if (grep { !defined $data->[$index]->{$_} } @pks ) {
1705 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
1706 my @ret = $self->populate($data);
1712 foreach my $rel (@rels) {
1713 next unless ref $data->[$index]->{$rel} eq "HASH";
1714 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1715 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1716 my $related = $result->result_source->_resolve_condition(
1717 $result->result_source->relationship_info($reverse)->{cond},
1722 delete $data->[$index]->{$rel};
1723 $data->[$index] = {%{$data->[$index]}, %$related};
1725 push @columns, keys %$related if $index == 0;
1729 ## inherit the data locked in the conditions of the resultset
1730 my ($rs_data) = $self->_merge_cond_with_data({});
1731 delete @{$rs_data}{@columns};
1732 my @inherit_cols = keys %$rs_data;
1733 my @inherit_data = values %$rs_data;
1735 ## do bulk insert on current row
1736 $self->result_source->storage->insert_bulk(
1737 $self->result_source,
1738 [@columns, @inherit_cols],
1739 [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
1742 ## do the has_many relationships
1743 foreach my $item (@$data) {
1745 foreach my $rel (@rels) {
1746 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1748 my $parent = $self->find({map { $_ => $item->{$_} } @pks})
1749 || $self->throw_exception('Cannot find the relating object.');
1751 my $child = $parent->$rel;
1753 my $related = $child->result_source->_resolve_condition(
1754 $parent->result_source->relationship_info($rel)->{cond},
1759 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1760 my @populate = map { {%$_, %$related} } @rows_to_add;
1762 $child->populate( \@populate );
1769 # populate() argumnets went over several incarnations
1770 # What we ultimately support is AoH
1771 sub _normalize_populate_args {
1772 my ($self, $arg) = @_;
1774 if (ref $arg eq 'ARRAY') {
1775 if (ref $arg->[0] eq 'HASH') {
1778 elsif (ref $arg->[0] eq 'ARRAY') {
1780 my @colnames = @{$arg->[0]};
1781 foreach my $values (@{$arg}[1 .. $#$arg]) {
1782 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
1788 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
1795 =item Arguments: none
1797 =item Return Value: $pager
1801 Return Value a L<Data::Page> object for the current resultset. Only makes
1802 sense for queries with a C<page> attribute.
1804 To get the full count of entries for a paged resultset, call
1805 C<total_entries> on the L<Data::Page> object.
1809 # make a wizard good for both a scalar and a hashref
1810 my $mk_lazy_count_wizard = sub {
1811 require Variable::Magic;
1813 my $stash = { total_rs => shift };
1814 my $slot = shift; # only used by the hashref magic
1816 my $magic = Variable::Magic::wizard (
1817 data => sub { $stash },
1823 # set value lazily, and dispell for good
1824 ${$_[0]} = $_[1]{total_rs}->count;
1825 Variable::Magic::dispell (${$_[0]}, $_[1]{magic_selfref});
1829 # an explicit set implies dispell as well
1830 # the unless() is to work around "fun and giggles" below
1831 Variable::Magic::dispell (${$_[0]}, $_[1]{magic_selfref})
1832 unless (caller(2))[3] eq 'DBIx::Class::ResultSet::pager';
1839 if ($_[2] eq $slot and !$_[1]{inactive}) {
1840 my $cnt = $_[1]{total_rs}->count;
1841 $_[0]->{$slot} = $cnt;
1843 # attempting to dispell in a fetch handle (works in store), seems
1844 # to invariable segfault on 5.10, 5.12, 5.13 :(
1845 # so use an inactivator instead
1846 #Variable::Magic::dispell (%{$_[0]}, $_[1]{magic_selfref});
1852 if (! $_[1]{inactive} and $_[2] eq $slot) {
1853 #Variable::Magic::dispell (%{$_[0]}, $_[1]{magic_selfref});
1855 unless (caller(2))[3] eq 'DBIx::Class::ResultSet::pager';
1862 $stash->{magic_selfref} = $magic;
1863 weaken ($stash->{magic_selfref}); # this fails on 5.8.1
1868 # the tie class for 5.8.1
1870 package DBIx::Class::__DBIC_LAZY_RS_COUNT__;
1871 use base qw/Tie::Hash/;
1873 sub FIRSTKEY { my $dummy = scalar keys %{$_[0]{data}}; each %{$_[0]{data}} }
1874 sub NEXTKEY { each %{$_[0]{data}} }
1875 sub EXISTS { exists $_[0]{data}{$_[1]} }
1876 sub DELETE { delete $_[0]{data}{$_[1]} }
1877 sub CLEAR { %{$_[0]{data}} = () }
1878 sub SCALAR { scalar %{$_[0]{data}} }
1881 $_[1]{data} = {%{$_[1]{selfref}}};
1882 %{$_[1]{selfref}} = ();
1883 Scalar::Util::weaken ($_[1]{selfref});
1884 return bless ($_[1], $_[0]);
1888 if ($_[1] eq $_[0]{slot}) {
1889 my $cnt = $_[0]{data}{$_[1]} = $_[0]{total_rs}->count;
1890 untie %{$_[0]{selfref}};
1891 %{$_[0]{selfref}} = %{$_[0]{data}};
1900 $_[0]{data}{$_[1]} = $_[2];
1901 if ($_[1] eq $_[0]{slot}) {
1902 untie %{$_[0]{selfref}};
1903 %{$_[0]{selfref}} = %{$_[0]{data}};
1912 return $self->{pager} if $self->{pager};
1914 if ($self->get_cache) {
1915 $self->throw_exception ('Pagers on cached resultsets are not supported');
1918 my $attrs = $self->{attrs};
1919 $self->throw_exception("Can't create pager for non-paged rs")
1920 unless $self->{attrs}{page};
1921 $attrs->{rows} ||= 10;
1923 # throw away the paging flags and re-run the count (possibly
1924 # with a subselect) to get the real total count
1925 my $count_attrs = { %$attrs };
1926 delete $count_attrs->{$_} for qw/rows offset page pager/;
1927 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
1930 ### the following may seem awkward and dirty, but it's a thought-experiment
1931 ### necessary for future development of DBIx::DS. Do *NOT* change this code
1932 ### before talking to ribasushi/mst
1934 my $pager = Data::Page->new(
1935 0, #start with an empty set
1937 $self->{attrs}{page},
1940 my $data_slot = 'total_entries';
1942 # Since we are interested in a cached value (once it's set - it's set), every
1943 # technique will detach from the magic-host once the time comes to fire the
1944 # ->count (or in the segfaulting case of >= 5.10 it will deactivate itself)
1946 if ($] < 5.008003) {
1947 # 5.8.1 throws 'Modification of a read-only value attempted' when one tries
1948 # to weakref the magic container :(
1950 tie (%$pager, 'DBIx::Class::__DBIC_LAZY_RS_COUNT__',
1951 { slot => $data_slot, total_rs => $total_rs, selfref => $pager }
1954 elsif ($] < 5.010) {
1955 # We can use magic on the hash value slot. It's interesting that the magic is
1956 # attached to the hash-slot, and does *not* stop working once I do the dummy
1957 # assignments after the cast()
1958 # tested on 5.8.3 and 5.8.9
1959 my $magic = $mk_lazy_count_wizard->($total_rs);
1960 Variable::Magic::cast ( $pager->{$data_slot}, $magic );
1962 # this is for fun and giggles
1963 $pager->{$data_slot} = -1;
1964 $pager->{$data_slot} = 0;
1966 # this does not work for scalars, but works with
1968 #my %vals = %$pager;
1973 # And the uvar magic
1974 # works on 5.10.1, 5.12.1 and 5.13.4 in its current form,
1975 # however see the wizard maker for more notes
1976 my $magic = $mk_lazy_count_wizard->($total_rs, $data_slot);
1977 Variable::Magic::cast ( %$pager, $magic );
1980 $pager->{$data_slot} = -1;
1981 $pager->{$data_slot} = 0;
1989 return $self->{pager} = $pager;
1996 =item Arguments: $page_number
1998 =item Return Value: $rs
2002 Returns a resultset for the $page_number page of the resultset on which page
2003 is called, where each page contains a number of rows equal to the 'rows'
2004 attribute set on the resultset (10 by default).
2009 my ($self, $page) = @_;
2010 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
2017 =item Arguments: \%vals
2019 =item Return Value: $rowobject
2023 Creates a new row object in the resultset's result class and returns
2024 it. The row is not inserted into the database at this point, call
2025 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
2026 will tell you whether the row object has been inserted or not.
2028 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2033 my ($self, $values) = @_;
2034 $self->throw_exception( "new_result needs a hash" )
2035 unless (ref $values eq 'HASH');
2037 my ($merged_cond, $cols_from_relations) = $self->_merge_cond_with_data($values);
2041 @$cols_from_relations
2042 ? (-cols_from_relations => $cols_from_relations)
2044 -source_handle => $self->_source_handle,
2045 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2048 return $self->result_class->new(\%new);
2051 # _merge_cond_with_data
2053 # Takes a simple hash of K/V data and returns its copy merged with the
2054 # condition already present on the resultset. Additionally returns an
2055 # arrayref of value/condition names, which were inferred from related
2056 # objects (this is needed for in-memory related objects)
2057 sub _merge_cond_with_data {
2058 my ($self, $data) = @_;
2060 my (%new_data, @cols_from_relations);
2062 my $alias = $self->{attrs}{alias};
2064 if (! defined $self->{cond}) {
2065 # just massage $data below
2067 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
2068 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
2069 @cols_from_relations = keys %new_data;
2071 elsif (ref $self->{cond} ne 'HASH') {
2072 $self->throw_exception(
2073 "Can't abstract implicit construct, resultset condition not a hash"
2077 # precendence must be given to passed values over values inherited from
2078 # the cond, so the order here is important.
2079 my $collapsed_cond = $self->_collapse_cond($self->{cond});
2080 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
2082 while ( my($col, $value) = each %implied ) {
2083 if (ref($value) eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '=') {
2084 $new_data{$col} = $value->{'='};
2087 $new_data{$col} = $value if $self->_is_deterministic_value($value);
2093 %{ $self->_remove_alias($data, $alias) },
2096 return (\%new_data, \@cols_from_relations);
2099 # _is_deterministic_value
2101 # Make an effor to strip non-deterministic values from the condition,
2102 # to make sure new_result chokes less
2104 sub _is_deterministic_value {
2107 my $ref_type = ref $value;
2108 return 1 if $ref_type eq '' || $ref_type eq 'SCALAR';
2109 return 1 if blessed $value;
2113 # _has_resolved_attr
2115 # determines if the resultset defines at least one
2116 # of the attributes supplied
2118 # used to determine if a subquery is neccessary
2120 # supports some virtual attributes:
2122 # This will scan for any joins being present on the resultset.
2123 # It is not a mere key-search but a deep inspection of {from}
2126 sub _has_resolved_attr {
2127 my ($self, @attr_names) = @_;
2129 my $attrs = $self->_resolved_attrs;
2133 for my $n (@attr_names) {
2134 if (grep { $n eq $_ } (qw/-join/) ) {
2135 $extra_checks{$n}++;
2139 my $attr = $attrs->{$n};
2141 next if not defined $attr;
2143 if (ref $attr eq 'HASH') {
2144 return 1 if keys %$attr;
2146 elsif (ref $attr eq 'ARRAY') {
2154 # a resolved join is expressed as a multi-level from
2156 $extra_checks{-join}
2158 ref $attrs->{from} eq 'ARRAY'
2160 @{$attrs->{from}} > 1
2168 # Recursively collapse the condition.
2170 sub _collapse_cond {
2171 my ($self, $cond, $collapsed) = @_;
2175 if (ref $cond eq 'ARRAY') {
2176 foreach my $subcond (@$cond) {
2177 next unless ref $subcond; # -or
2178 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2181 elsif (ref $cond eq 'HASH') {
2182 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2183 foreach my $subcond (@{$cond->{-and}}) {
2184 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2188 foreach my $col (keys %$cond) {
2189 my $value = $cond->{$col};
2190 $collapsed->{$col} = $value;
2200 # Remove the specified alias from the specified query hash. A copy is made so
2201 # the original query is not modified.
2204 my ($self, $query, $alias) = @_;
2206 my %orig = %{ $query || {} };
2209 foreach my $key (keys %orig) {
2211 $unaliased{$key} = $orig{$key};
2214 $unaliased{$1} = $orig{$key}
2215 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2225 =item Arguments: none
2227 =item Return Value: \[ $sql, @bind ]
2231 Returns the SQL query and bind vars associated with the invocant.
2233 This is generally used as the RHS for a subquery.
2240 my $attrs = $self->_resolved_attrs_copy;
2245 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2246 # $sql also has no wrapping parenthesis in list ctx
2248 my $sqlbind = $self->result_source->storage
2249 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2258 =item Arguments: \%vals, \%attrs?
2260 =item Return Value: $rowobject
2264 my $artist = $schema->resultset('Artist')->find_or_new(
2265 { artist => 'fred' }, { key => 'artists' });
2267 $cd->cd_to_producer->find_or_new({ producer => $producer },
2268 { key => 'primary });
2270 Find an existing record from this resultset, based on its primary
2271 key, or a unique constraint. If none exists, instantiate a new result
2272 object and return it. The object will not be saved into your storage
2273 until you call L<DBIx::Class::Row/insert> on it.
2275 You most likely want this method when looking for existing rows using
2276 a unique constraint that is not the primary key, or looking for
2279 If you want objects to be saved immediately, use L</find_or_create>
2282 B<Note>: Take care when using C<find_or_new> with a table having
2283 columns with default values that you intend to be automatically
2284 supplied by the database (e.g. an auto_increment primary key column).
2285 In normal usage, the value of such columns should NOT be included at
2286 all in the call to C<find_or_new>, even when set to C<undef>.
2292 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2293 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2294 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2297 return $self->new_result($hash);
2304 =item Arguments: \%vals
2306 =item Return Value: a L<DBIx::Class::Row> $object
2310 Attempt to create a single new row or a row with multiple related rows
2311 in the table represented by the resultset (and related tables). This
2312 will not check for duplicate rows before inserting, use
2313 L</find_or_create> to do that.
2315 To create one row for this resultset, pass a hashref of key/value
2316 pairs representing the columns of the table and the values you wish to
2317 store. If the appropriate relationships are set up, foreign key fields
2318 can also be passed an object representing the foreign row, and the
2319 value will be set to its primary key.
2321 To create related objects, pass a hashref of related-object column values
2322 B<keyed on the relationship name>. If the relationship is of type C<multi>
2323 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2324 The process will correctly identify columns holding foreign keys, and will
2325 transparently populate them from the keys of the corresponding relation.
2326 This can be applied recursively, and will work correctly for a structure
2327 with an arbitrary depth and width, as long as the relationships actually
2328 exists and the correct column data has been supplied.
2331 Instead of hashrefs of plain related data (key/value pairs), you may
2332 also pass new or inserted objects. New objects (not inserted yet, see
2333 L</new>), will be inserted into their appropriate tables.
2335 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2337 Example of creating a new row.
2339 $person_rs->create({
2340 name=>"Some Person",
2341 email=>"somebody@someplace.com"
2344 Example of creating a new row and also creating rows in a related C<has_many>
2345 or C<has_one> resultset. Note Arrayref.
2348 { artistid => 4, name => 'Manufactured Crap', cds => [
2349 { title => 'My First CD', year => 2006 },
2350 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2355 Example of creating a new row and also creating a row in a related
2356 C<belongs_to> resultset. Note Hashref.
2359 title=>"Music for Silly Walks",
2362 name=>"Silly Musician",
2370 When subclassing ResultSet never attempt to override this method. Since
2371 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2372 lot of the internals simply never call it, so your override will be
2373 bypassed more often than not. Override either L<new|DBIx::Class::Row/new>
2374 or L<insert|DBIx::Class::Row/insert> depending on how early in the
2375 L</create> process you need to intervene.
2382 my ($self, $attrs) = @_;
2383 $self->throw_exception( "create needs a hashref" )
2384 unless ref $attrs eq 'HASH';
2385 return $self->new_result($attrs)->insert;
2388 =head2 find_or_create
2392 =item Arguments: \%vals, \%attrs?
2394 =item Return Value: $rowobject
2398 $cd->cd_to_producer->find_or_create({ producer => $producer },
2399 { key => 'primary' });
2401 Tries to find a record based on its primary key or unique constraints; if none
2402 is found, creates one and returns that instead.
2404 my $cd = $schema->resultset('CD')->find_or_create({
2406 artist => 'Massive Attack',
2407 title => 'Mezzanine',
2411 Also takes an optional C<key> attribute, to search by a specific key or unique
2412 constraint. For example:
2414 my $cd = $schema->resultset('CD')->find_or_create(
2416 artist => 'Massive Attack',
2417 title => 'Mezzanine',
2419 { key => 'cd_artist_title' }
2422 B<Note>: Because find_or_create() reads from the database and then
2423 possibly inserts based on the result, this method is subject to a race
2424 condition. Another process could create a record in the table after
2425 the find has completed and before the create has started. To avoid
2426 this problem, use find_or_create() inside a transaction.
2428 B<Note>: Take care when using C<find_or_create> with a table having
2429 columns with default values that you intend to be automatically
2430 supplied by the database (e.g. an auto_increment primary key column).
2431 In normal usage, the value of such columns should NOT be included at
2432 all in the call to C<find_or_create>, even when set to C<undef>.
2434 See also L</find> and L</update_or_create>. For information on how to declare
2435 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2439 sub find_or_create {
2441 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2442 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2443 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2446 return $self->create($hash);
2449 =head2 update_or_create
2453 =item Arguments: \%col_values, { key => $unique_constraint }?
2455 =item Return Value: $rowobject
2459 $resultset->update_or_create({ col => $val, ... });
2461 First, searches for an existing row matching one of the unique constraints
2462 (including the primary key) on the source of this resultset. If a row is
2463 found, updates it with the other given column values. Otherwise, creates a new
2466 Takes an optional C<key> attribute to search on a specific unique constraint.
2469 # In your application
2470 my $cd = $schema->resultset('CD')->update_or_create(
2472 artist => 'Massive Attack',
2473 title => 'Mezzanine',
2476 { key => 'cd_artist_title' }
2479 $cd->cd_to_producer->update_or_create({
2480 producer => $producer,
2487 If no C<key> is specified, it searches on all unique constraints defined on the
2488 source, including the primary key.
2490 If the C<key> is specified as C<primary>, it searches only on the primary key.
2492 See also L</find> and L</find_or_create>. For information on how to declare
2493 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2495 B<Note>: Take care when using C<update_or_create> with a table having
2496 columns with default values that you intend to be automatically
2497 supplied by the database (e.g. an auto_increment primary key column).
2498 In normal usage, the value of such columns should NOT be included at
2499 all in the call to C<update_or_create>, even when set to C<undef>.
2503 sub update_or_create {
2505 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2506 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2508 my $row = $self->find($cond, $attrs);
2510 $row->update($cond);
2514 return $self->create($cond);
2517 =head2 update_or_new
2521 =item Arguments: \%col_values, { key => $unique_constraint }?
2523 =item Return Value: $rowobject
2527 $resultset->update_or_new({ col => $val, ... });
2529 First, searches for an existing row matching one of the unique constraints
2530 (including the primary key) on the source of this resultset. If a row is
2531 found, updates it with the other given column values. Otherwise, instantiate
2532 a new result object and return it. The object will not be saved into your storage
2533 until you call L<DBIx::Class::Row/insert> on it.
2535 Takes an optional C<key> attribute to search on a specific unique constraint.
2538 # In your application
2539 my $cd = $schema->resultset('CD')->update_or_new(
2541 artist => 'Massive Attack',
2542 title => 'Mezzanine',
2545 { key => 'cd_artist_title' }
2548 if ($cd->in_storage) {
2549 # the cd was updated
2552 # the cd is not yet in the database, let's insert it
2556 B<Note>: Take care when using C<update_or_new> with a table having
2557 columns with default values that you intend to be automatically
2558 supplied by the database (e.g. an auto_increment primary key column).
2559 In normal usage, the value of such columns should NOT be included at
2560 all in the call to C<update_or_new>, even when set to C<undef>.
2562 See also L</find>, L</find_or_create> and L</find_or_new>.
2568 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2569 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2571 my $row = $self->find( $cond, $attrs );
2572 if ( defined $row ) {
2573 $row->update($cond);
2577 return $self->new_result($cond);
2584 =item Arguments: none
2586 =item Return Value: \@cache_objects | undef
2590 Gets the contents of the cache for the resultset, if the cache is set.
2592 The cache is populated either by using the L</prefetch> attribute to
2593 L</search> or by calling L</set_cache>.
2605 =item Arguments: \@cache_objects
2607 =item Return Value: \@cache_objects
2611 Sets the contents of the cache for the resultset. Expects an arrayref
2612 of objects of the same class as those produced by the resultset. Note that
2613 if the cache is set the resultset will return the cached objects rather
2614 than re-querying the database even if the cache attr is not set.
2616 The contents of the cache can also be populated by using the
2617 L</prefetch> attribute to L</search>.
2622 my ( $self, $data ) = @_;
2623 $self->throw_exception("set_cache requires an arrayref")
2624 if defined($data) && (ref $data ne 'ARRAY');
2625 $self->{all_cache} = $data;
2632 =item Arguments: none
2634 =item Return Value: undef
2638 Clears the cache for the resultset.
2643 shift->set_cache(undef);
2650 =item Arguments: none
2652 =item Return Value: true, if the resultset has been paginated
2660 return !!$self->{attrs}{page};
2667 =item Arguments: none
2669 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2677 return scalar $self->result_source->storage->_extract_order_columns($self->{attrs}{order_by});
2680 =head2 related_resultset
2684 =item Arguments: $relationship_name
2686 =item Return Value: $resultset
2690 Returns a related resultset for the supplied relationship name.
2692 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2696 sub related_resultset {
2697 my ($self, $rel) = @_;
2699 $self->{related_resultsets} ||= {};
2700 return $self->{related_resultsets}{$rel} ||= do {
2701 my $rsrc = $self->result_source;
2702 my $rel_info = $rsrc->relationship_info($rel);
2704 $self->throw_exception(
2705 "search_related: result source '" . $rsrc->source_name .
2706 "' has no such relationship $rel")
2709 my $attrs = $self->_chain_relationship($rel);
2711 my $join_count = $attrs->{seen_join}{$rel};
2713 my $alias = $self->result_source->storage
2714 ->relname_to_table_alias($rel, $join_count);
2716 # since this is search_related, and we already slid the select window inwards
2717 # (the select/as attrs were deleted in the beginning), we need to flip all
2718 # left joins to inner, so we get the expected results
2719 # read the comment on top of the actual function to see what this does
2720 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
2723 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2724 delete @{$attrs}{qw(result_class alias)};
2728 if (my $cache = $self->get_cache) {
2729 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2730 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
2735 my $rel_source = $rsrc->related_source($rel);
2739 # The reason we do this now instead of passing the alias to the
2740 # search_rs below is that if you wrap/overload resultset on the
2741 # source you need to know what alias it's -going- to have for things
2742 # to work sanely (e.g. RestrictWithObject wants to be able to add
2743 # extra query restrictions, and these may need to be $alias.)
2745 my $rel_attrs = $rel_source->resultset_attributes;
2746 local $rel_attrs->{alias} = $alias;
2748 $rel_source->resultset
2752 where => $attrs->{where},
2755 $new->set_cache($new_cache) if $new_cache;
2760 =head2 current_source_alias
2764 =item Arguments: none
2766 =item Return Value: $source_alias
2770 Returns the current table alias for the result source this resultset is built
2771 on, that will be used in the SQL query. Usually it is C<me>.
2773 Currently the source alias that refers to the result set returned by a
2774 L</search>/L</find> family method depends on how you got to the resultset: it's
2775 C<me> by default, but eg. L</search_related> aliases it to the related result
2776 source name (and keeps C<me> referring to the original result set). The long
2777 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
2778 (and make this method unnecessary).
2780 Thus it's currently necessary to use this method in predefined queries (see
2781 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
2782 source alias of the current result set:
2784 # in a result set class
2786 my ($self, $user) = @_;
2788 my $me = $self->current_source_alias;
2790 return $self->search(
2791 "$me.modified" => $user->id,
2797 sub current_source_alias {
2800 return ($self->{attrs} || {})->{alias} || 'me';
2803 =head2 as_subselect_rs
2807 =item Arguments: none
2809 =item Return Value: $resultset
2813 Act as a barrier to SQL symbols. The resultset provided will be made into a
2814 "virtual view" by including it as a subquery within the from clause. From this
2815 point on, any joined tables are inaccessible to ->search on the resultset (as if
2816 it were simply where-filtered without joins). For example:
2818 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
2820 # 'x' now pollutes the query namespace
2822 # So the following works as expected
2823 my $ok_rs = $rs->search({'x.other' => 1});
2825 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
2826 # def) we look for one row with contradictory terms and join in another table
2827 # (aliased 'x_2') which we never use
2828 my $broken_rs = $rs->search({'x.name' => 'def'});
2830 my $rs2 = $rs->as_subselect_rs;
2832 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
2833 my $not_joined_rs = $rs2->search({'x.other' => 1});
2835 # works as expected: finds a 'table' row related to two x rows (abc and def)
2836 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
2838 Another example of when one might use this would be to select a subset of
2839 columns in a group by clause:
2841 my $rs = $schema->resultset('Bar')->search(undef, {
2842 group_by => [qw{ id foo_id baz_id }],
2843 })->as_subselect_rs->search(undef, {
2844 columns => [qw{ id foo_id }]
2847 In the above example normally columns would have to be equal to the group by,
2848 but because we isolated the group by into a subselect the above works.
2852 sub as_subselect_rs {
2855 my $attrs = $self->_resolved_attrs;
2857 my $fresh_rs = (ref $self)->new (
2858 $self->result_source
2861 # these pieces will be locked in the subquery
2862 delete $fresh_rs->{cond};
2863 delete @{$fresh_rs->{attrs}}{qw/where bind/};
2865 return $fresh_rs->search( {}, {
2867 $attrs->{alias} => $self->as_query,
2868 -alias => $attrs->{alias},
2869 -source_handle => $self->result_source->handle,
2871 alias => $attrs->{alias},
2875 # This code is called by search_related, and makes sure there
2876 # is clear separation between the joins before, during, and
2877 # after the relationship. This information is needed later
2878 # in order to properly resolve prefetch aliases (any alias
2879 # with a relation_chain_depth less than the depth of the
2880 # current prefetch is not considered)
2882 # The increments happen twice per join. An even number means a
2883 # relationship specified via a search_related, whereas an odd
2884 # number indicates a join/prefetch added via attributes
2886 # Also this code will wrap the current resultset (the one we
2887 # chain to) in a subselect IFF it contains limiting attributes
2888 sub _chain_relationship {
2889 my ($self, $rel) = @_;
2890 my $source = $self->result_source;
2891 my $attrs = { %{$self->{attrs}||{}} };
2893 # we need to take the prefetch the attrs into account before we
2894 # ->_resolve_join as otherwise they get lost - captainL
2895 my $join = $self->_merge_attr( $attrs->{join}, $attrs->{prefetch} );
2897 delete @{$attrs}{qw/join prefetch collapse group_by distinct select as columns +select +as +columns/};
2899 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
2902 my @force_subq_attrs = qw/offset rows group_by having/;
2905 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
2907 $self->_has_resolved_attr (@force_subq_attrs)
2909 # Nuke the prefetch (if any) before the new $rs attrs
2910 # are resolved (prefetch is useless - we are wrapping
2911 # a subquery anyway).
2912 my $rs_copy = $self->search;
2913 $rs_copy->{attrs}{join} = $self->_merge_attr (
2914 $rs_copy->{attrs}{join},
2915 delete $rs_copy->{attrs}{prefetch},
2919 -source_handle => $source->handle,
2920 -alias => $attrs->{alias},
2921 $attrs->{alias} => $rs_copy->as_query,
2923 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
2924 $seen->{-relation_chain_depth} = 0;
2926 elsif ($attrs->{from}) { #shallow copy suffices
2927 $from = [ @{$attrs->{from}} ];
2931 -source_handle => $source->handle,
2932 -alias => $attrs->{alias},
2933 $attrs->{alias} => $source->from,
2937 my $jpath = ($seen->{-relation_chain_depth})
2938 ? $from->[-1][0]{-join_path}
2941 my @requested_joins = $source->_resolve_join(
2948 push @$from, @requested_joins;
2950 $seen->{-relation_chain_depth}++;
2952 # if $self already had a join/prefetch specified on it, the requested
2953 # $rel might very well be already included. What we do in this case
2954 # is effectively a no-op (except that we bump up the chain_depth on
2955 # the join in question so we could tell it *is* the search_related)
2958 # we consider the last one thus reverse
2959 for my $j (reverse @requested_joins) {
2960 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
2961 if ($rel eq $last_j) {
2962 $j->[0]{-relation_chain_depth}++;
2968 unless ($already_joined) {
2969 push @$from, $source->_resolve_join(
2977 $seen->{-relation_chain_depth}++;
2979 return {%$attrs, from => $from, seen_join => $seen};
2982 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
2983 sub _resolved_attrs_copy {
2985 return { %{$self->_resolved_attrs (@_)} };
2988 sub _resolved_attrs {
2990 return $self->{_attrs} if $self->{_attrs};
2992 my $attrs = { %{ $self->{attrs} || {} } };
2993 my $source = $self->result_source;
2994 my $alias = $attrs->{alias};
2996 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
2999 # build columns (as long as select isn't set) into a set of as/select hashes
3000 unless ( $attrs->{select} ) {
3003 if ( ref $attrs->{columns} eq 'ARRAY' ) {
3004 @cols = @{ delete $attrs->{columns}}
3005 } elsif ( defined $attrs->{columns} ) {
3006 @cols = delete $attrs->{columns}
3008 @cols = $source->columns
3012 if ( ref $_ eq 'HASH' ) {
3015 my $key = /^\Q${alias}.\E(.+)$/
3021 push @colbits, { $key => $value };
3026 # add the additional columns on
3027 foreach (qw{include_columns +columns}) {
3028 if ( $attrs->{$_} ) {
3029 my @list = ( ref($attrs->{$_}) eq 'ARRAY' )
3030 ? @{ delete $attrs->{$_} }
3031 : delete $attrs->{$_};
3033 if ( ref($_) eq 'HASH' ) {
3036 my $key = ( split /\./, $_ )[-1];
3037 my $value = ( /\./ ? $_ : "$alias.$_" );
3038 push @colbits, { $key => $value };
3044 # start with initial select items
3045 if ( $attrs->{select} ) {
3047 ( ref $attrs->{select} eq 'ARRAY' )
3048 ? [ @{ $attrs->{select} } ]
3049 : [ $attrs->{select} ];
3051 if ( $attrs->{as} ) {
3054 ref $attrs->{as} eq 'ARRAY'
3055 ? [ @{ $attrs->{as} } ]
3059 $attrs->{as} = [ map {
3060 m/^\Q${alias}.\E(.+)$/
3063 } @{ $attrs->{select} }
3069 # otherwise we intialise select & as to empty
3070 $attrs->{select} = [];
3074 # now add colbits to select/as
3075 push @{ $attrs->{select} }, map values %{$_}, @colbits;
3076 push @{ $attrs->{as} }, map keys %{$_}, @colbits;
3078 if ( my $adds = delete $attrs->{'+select'} ) {
3079 $adds = [$adds] unless ref $adds eq 'ARRAY';
3080 push @{ $attrs->{select} },
3081 map { /\./ || ref $_ ? $_ : "$alias.$_" } @$adds;
3083 if ( my $adds = delete $attrs->{'+as'} ) {
3084 $adds = [$adds] unless ref $adds eq 'ARRAY';
3085 push @{ $attrs->{as} }, @$adds;
3088 $attrs->{from} ||= [{
3089 -source_handle => $source->handle,
3090 -alias => $self->{attrs}{alias},
3091 $self->{attrs}{alias} => $source->from,
3094 if ( $attrs->{join} || $attrs->{prefetch} ) {
3096 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3097 if ref $attrs->{from} ne 'ARRAY';
3099 my $join = delete $attrs->{join} || {};
3101 if ( defined $attrs->{prefetch} ) {
3102 $join = $self->_merge_attr( $join, $attrs->{prefetch} );
3105 $attrs->{from} = # have to copy here to avoid corrupting the original
3107 @{ $attrs->{from} },
3108 $source->_resolve_join(
3111 { %{ $attrs->{seen_join} || {} } },
3112 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3113 ? $attrs->{from}[-1][0]{-join_path}
3120 if ( defined $attrs->{order_by} ) {
3121 $attrs->{order_by} = (
3122 ref( $attrs->{order_by} ) eq 'ARRAY'
3123 ? [ @{ $attrs->{order_by} } ]
3124 : [ $attrs->{order_by} || () ]
3128 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3129 $attrs->{group_by} = [ $attrs->{group_by} ];
3132 # generate the distinct induced group_by early, as prefetch will be carried via a
3133 # subquery (since a group_by is present)
3134 if (delete $attrs->{distinct}) {
3135 if ($attrs->{group_by}) {
3136 carp ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3139 my $storage = $self->result_source->schema->storage;
3140 my $rs_column_list = $storage->_resolve_column_info ($attrs->{from});
3142 my $group_spec = $attrs->{group_by} = [];
3145 for (@{$attrs->{select}}) {
3146 if (! ref($_) or ref ($_) ne 'HASH' ) {
3147 push @$group_spec, $_;
3149 if ($rs_column_list->{$_} and $_ !~ /\./ ) {
3150 # add a fully qualified version as well
3151 $group_index{"$rs_column_list->{$_}{-source_alias}.$_"}++;
3155 # add any order_by parts that are not already present in the group_by
3156 # we need to be careful not to add any named functions/aggregates
3157 # i.e. select => [ ... { count => 'foo', -as 'foocount' } ... ]
3158 for my $chunk ($storage->_extract_order_columns($attrs->{order_by})) {
3160 # only consider real columns (for functions the user got to do an explicit group_by)
3161 my $colinfo = $rs_column_list->{$chunk}
3164 $chunk = "$colinfo->{-source_alias}.$chunk" if $chunk !~ /\./;
3165 push @$group_spec, $chunk unless $group_index{$chunk}++;
3170 $attrs->{collapse} ||= {};
3171 if ( my $prefetch = delete $attrs->{prefetch} ) {
3172 $prefetch = $self->_merge_attr( {}, $prefetch );
3174 my $prefetch_ordering = [];
3176 # this is a separate structure (we don't look in {from} directly)
3177 # as the resolver needs to shift things off the lists to work
3178 # properly (identical-prefetches on different branches)
3180 if (ref $attrs->{from} eq 'ARRAY') {
3182 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3184 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3185 next unless $j->[0]{-alias};
3186 next unless $j->[0]{-join_path};
3187 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3189 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3192 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3193 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3198 $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
3200 # we need to somehow mark which columns came from prefetch
3201 $attrs->{_prefetch_select} = [ map { $_->[0] } @prefetch ];
3203 push @{ $attrs->{select} }, @{$attrs->{_prefetch_select}};
3204 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
3206 push( @{$attrs->{order_by}}, @$prefetch_ordering );
3207 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
3210 # if both page and offset are specified, produce a combined offset
3211 # even though it doesn't make much sense, this is what pre 081xx has
3213 if (my $page = delete $attrs->{page}) {
3215 ($attrs->{rows} * ($page - 1))
3217 ($attrs->{offset} || 0)
3221 return $self->{_attrs} = $attrs;
3225 my ($self, $attr) = @_;
3227 if (ref $attr eq 'HASH') {
3228 return $self->_rollout_hash($attr);
3229 } elsif (ref $attr eq 'ARRAY') {
3230 return $self->_rollout_array($attr);
3236 sub _rollout_array {
3237 my ($self, $attr) = @_;
3240 foreach my $element (@{$attr}) {
3241 if (ref $element eq 'HASH') {
3242 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3243 } elsif (ref $element eq 'ARRAY') {
3244 # XXX - should probably recurse here
3245 push( @rolled_array, @{$self->_rollout_array($element)} );
3247 push( @rolled_array, $element );
3250 return \@rolled_array;
3254 my ($self, $attr) = @_;
3257 foreach my $key (keys %{$attr}) {
3258 push( @rolled_array, { $key => $attr->{$key} } );
3260 return \@rolled_array;
3263 sub _calculate_score {
3264 my ($self, $a, $b) = @_;
3266 if (defined $a xor defined $b) {
3269 elsif (not defined $a) {
3273 if (ref $b eq 'HASH') {
3274 my ($b_key) = keys %{$b};
3275 if (ref $a eq 'HASH') {
3276 my ($a_key) = keys %{$a};
3277 if ($a_key eq $b_key) {
3278 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3283 return ($a eq $b_key) ? 1 : 0;
3286 if (ref $a eq 'HASH') {
3287 my ($a_key) = keys %{$a};
3288 return ($b eq $a_key) ? 1 : 0;
3290 return ($b eq $a) ? 1 : 0;
3296 my ($self, $orig, $import) = @_;
3298 return $import unless defined($orig);
3299 return $orig unless defined($import);
3301 $orig = $self->_rollout_attr($orig);
3302 $import = $self->_rollout_attr($import);
3305 foreach my $import_element ( @{$import} ) {
3306 # find best candidate from $orig to merge $b_element into
3307 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3308 foreach my $orig_element ( @{$orig} ) {
3309 my $score = $self->_calculate_score( $orig_element, $import_element );
3310 if ($score > $best_candidate->{score}) {
3311 $best_candidate->{position} = $position;
3312 $best_candidate->{score} = $score;
3316 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3318 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3319 push( @{$orig}, $import_element );
3321 my $orig_best = $orig->[$best_candidate->{position}];
3322 # merge orig_best and b_element together and replace original with merged
3323 if (ref $orig_best ne 'HASH') {
3324 $orig->[$best_candidate->{position}] = $import_element;
3325 } elsif (ref $import_element eq 'HASH') {
3326 my ($key) = keys %{$orig_best};
3327 $orig->[$best_candidate->{position}] = { $key => $self->_merge_attr($orig_best->{$key}, $import_element->{$key}) };
3330 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3340 $self->_source_handle($_[0]->handle);
3342 $self->_source_handle->resolve;
3346 =head2 throw_exception
3348 See L<DBIx::Class::Schema/throw_exception> for details.
3352 sub throw_exception {
3355 if (ref $self && $self->_source_handle->schema) {
3356 $self->_source_handle->schema->throw_exception(@_)
3359 DBIx::Class::Exception->throw(@_);
3363 # XXX: FIXME: Attributes docs need clearing up
3367 Attributes are used to refine a ResultSet in various ways when
3368 searching for data. They can be passed to any method which takes an
3369 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3372 These are in no particular order:
3378 =item Value: ( $order_by | \@order_by | \%order_by )
3382 Which column(s) to order the results by.
3384 [The full list of suitable values is documented in
3385 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3388 If a single column name, or an arrayref of names is supplied, the
3389 argument is passed through directly to SQL. The hashref syntax allows
3390 for connection-agnostic specification of ordering direction:
3392 For descending order:
3394 order_by => { -desc => [qw/col1 col2 col3/] }
3396 For explicit ascending order:
3398 order_by => { -asc => 'col' }
3400 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3401 supported, although you are strongly encouraged to use the hashref
3402 syntax as outlined above.
3408 =item Value: \@columns
3412 Shortcut to request a particular set of columns to be retrieved. Each
3413 column spec may be a string (a table column name), or a hash (in which
3414 case the key is the C<as> value, and the value is used as the C<select>
3415 expression). Adds C<me.> onto the start of any column without a C<.> in
3416 it and sets C<select> from that, then auto-populates C<as> from
3417 C<select> as normal. (You may also use the C<cols> attribute, as in
3418 earlier versions of DBIC.)
3420 Essentially C<columns> does the same as L</select> and L</as>.
3422 columns => [ 'foo', { bar => 'baz' } ]
3426 select => [qw/foo baz/],
3433 =item Value: \@columns
3437 Indicates additional columns to be selected from storage. Works the same
3438 as L</columns> but adds columns to the selection. (You may also use the
3439 C<include_columns> attribute, as in earlier versions of DBIC). For
3442 $schema->resultset('CD')->search(undef, {
3443 '+columns' => ['artist.name'],
3447 would return all CDs and include a 'name' column to the information
3448 passed to object inflation. Note that the 'artist' is the name of the
3449 column (or relationship) accessor, and 'name' is the name of the column
3450 accessor in the related table.
3452 =head2 include_columns
3456 =item Value: \@columns
3460 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3466 =item Value: \@select_columns
3470 Indicates which columns should be selected from the storage. You can use
3471 column names, or in the case of RDBMS back ends, function or stored procedure
3474 $rs = $schema->resultset('Employee')->search(undef, {
3477 { count => 'employeeid' },
3478 { max => { length => 'name' }, -as => 'longest_name' }
3483 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
3485 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
3486 use L</select>, to instruct DBIx::Class how to store the result of the column.
3487 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
3488 identifier aliasing. You can however alias a function, so you can use it in
3489 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
3490 attribute> supplied as shown in the example above.
3496 Indicates additional columns to be selected from storage. Works the same as
3497 L</select> but adds columns to the default selection, instead of specifying
3506 Indicates additional column names for those added via L</+select>. See L</as>.
3514 =item Value: \@inflation_names
3518 Indicates column names for object inflation. That is L</as> indicates the
3519 slot name in which the column value will be stored within the
3520 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
3521 identifier by the C<get_column> method (or via the object accessor B<if one
3522 with the same name already exists>) as shown below. The L</as> attribute has
3523 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
3525 $rs = $schema->resultset('Employee')->search(undef, {
3528 { count => 'employeeid' },
3529 { max => { length => 'name' }, -as => 'longest_name' }
3538 If the object against which the search is performed already has an accessor
3539 matching a column name specified in C<as>, the value can be retrieved using
3540 the accessor as normal:
3542 my $name = $employee->name();
3544 If on the other hand an accessor does not exist in the object, you need to
3545 use C<get_column> instead:
3547 my $employee_count = $employee->get_column('employee_count');
3549 You can create your own accessors if required - see
3550 L<DBIx::Class::Manual::Cookbook> for details.
3556 =item Value: ($rel_name | \@rel_names | \%rel_names)
3560 Contains a list of relationships that should be joined for this query. For
3563 # Get CDs by Nine Inch Nails
3564 my $rs = $schema->resultset('CD')->search(
3565 { 'artist.name' => 'Nine Inch Nails' },
3566 { join => 'artist' }
3569 Can also contain a hash reference to refer to the other relation's relations.
3572 package MyApp::Schema::Track;
3573 use base qw/DBIx::Class/;
3574 __PACKAGE__->table('track');
3575 __PACKAGE__->add_columns(qw/trackid cd position title/);
3576 __PACKAGE__->set_primary_key('trackid');
3577 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3580 # In your application
3581 my $rs = $schema->resultset('Artist')->search(
3582 { 'track.title' => 'Teardrop' },
3584 join => { cd => 'track' },
3585 order_by => 'artist.name',
3589 You need to use the relationship (not the table) name in conditions,
3590 because they are aliased as such. The current table is aliased as "me", so
3591 you need to use me.column_name in order to avoid ambiguity. For example:
3593 # Get CDs from 1984 with a 'Foo' track
3594 my $rs = $schema->resultset('CD')->search(
3597 'tracks.name' => 'Foo'
3599 { join => 'tracks' }
3602 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3603 similarly for a third time). For e.g.
3605 my $rs = $schema->resultset('Artist')->search({
3606 'cds.title' => 'Down to Earth',
3607 'cds_2.title' => 'Popular',
3609 join => [ qw/cds cds/ ],
3612 will return a set of all artists that have both a cd with title 'Down
3613 to Earth' and a cd with title 'Popular'.
3615 If you want to fetch related objects from other tables as well, see C<prefetch>
3618 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3624 =item Value: ($rel_name | \@rel_names | \%rel_names)
3628 Contains one or more relationships that should be fetched along with
3629 the main query (when they are accessed afterwards the data will
3630 already be available, without extra queries to the database). This is
3631 useful for when you know you will need the related objects, because it
3632 saves at least one query:
3634 my $rs = $schema->resultset('Tag')->search(
3643 The initial search results in SQL like the following:
3645 SELECT tag.*, cd.*, artist.* FROM tag
3646 JOIN cd ON tag.cd = cd.cdid
3647 JOIN artist ON cd.artist = artist.artistid
3649 L<DBIx::Class> has no need to go back to the database when we access the
3650 C<cd> or C<artist> relationships, which saves us two SQL statements in this
3653 Simple prefetches will be joined automatically, so there is no need
3654 for a C<join> attribute in the above search.
3656 C<prefetch> can be used with the following relationship types: C<belongs_to>,
3657 C<has_one> (or if you're using C<add_relationship>, any relationship declared
3658 with an accessor type of 'single' or 'filter'). A more complex example that
3659 prefetches an artists cds, the tracks on those cds, and the tags associated
3660 with that artist is given below (assuming many-to-many from artists to tags):
3662 my $rs = $schema->resultset('Artist')->search(
3666 { cds => 'tracks' },
3667 { artist_tags => 'tags' }
3673 B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
3674 attributes will be ignored.
3676 B<CAVEATs>: Prefetch does a lot of deep magic. As such, it may not behave
3677 exactly as you might expect.
3683 Prefetch uses the L</cache> to populate the prefetched relationships. This
3684 may or may not be what you want.
3688 If you specify a condition on a prefetched relationship, ONLY those
3689 rows that match the prefetched condition will be fetched into that relationship.
3690 This means that adding prefetch to a search() B<may alter> what is returned by
3691 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
3693 my $artist_rs = $schema->resultset('Artist')->search({
3699 my $count = $artist_rs->first->cds->count;
3701 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
3703 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
3705 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
3707 that cmp_ok() may or may not pass depending on the datasets involved. This
3708 behavior may or may not survive the 0.09 transition.
3720 Makes the resultset paged and specifies the page to retrieve. Effectively
3721 identical to creating a non-pages resultset and then calling ->page($page)
3724 If L<rows> attribute is not specified it defaults to 10 rows per page.
3726 When you have a paged resultset, L</count> will only return the number
3727 of rows in the page. To get the total, use the L</pager> and call
3728 C<total_entries> on it.
3738 Specifies the maximum number of rows for direct retrieval or the number of
3739 rows per page if the page attribute or method is used.
3745 =item Value: $offset
3749 Specifies the (zero-based) row number for the first row to be returned, or the
3750 of the first row of the first page if paging is used.
3756 =item Value: \@columns
3760 A arrayref of columns to group by. Can include columns of joined tables.
3762 group_by => [qw/ column1 column2 ... /]
3768 =item Value: $condition
3772 HAVING is a select statement attribute that is applied between GROUP BY and
3773 ORDER BY. It is applied to the after the grouping calculations have been
3776 having => { 'count(employee)' => { '>=', 100 } }
3782 =item Value: (0 | 1)
3786 Set to 1 to group by all columns. If the resultset already has a group_by
3787 attribute, this setting is ignored and an appropriate warning is issued.
3793 Adds to the WHERE clause.
3795 # only return rows WHERE deleted IS NULL for all searches
3796 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
3798 Can be overridden by passing C<< { where => undef } >> as an attribute
3805 Set to 1 to cache search results. This prevents extra SQL queries if you
3806 revisit rows in your ResultSet:
3808 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
3810 while( my $artist = $resultset->next ) {
3814 $rs->first; # without cache, this would issue a query
3816 By default, searches are not cached.
3818 For more examples of using these attributes, see
3819 L<DBIx::Class::Manual::Cookbook>.
3825 =item Value: ( 'update' | 'shared' )
3829 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT