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 $call_attrs = pop(@_) if @_ > 1 and ref $_[-1] eq 'HASH';
281 # see if we can keep the cache (no $rs changes)
283 my %safe = (alias => 1, cache => 1);
284 if ( ! List::Util::first { !$safe{$_} } keys %$call_attrs and (
287 ref $_[0] eq 'HASH' && ! keys %{$_[0]}
289 ref $_[0] eq 'ARRAY' && ! @{$_[0]}
291 $cache = $self->get_cache;
294 my $old_attrs = { %{$self->{attrs}} };
295 my $old_having = delete $old_attrs->{having};
296 my $old_where = delete $old_attrs->{where};
298 # reset the selector list
299 if (List::Util::first { exists $call_attrs->{$_} } qw{columns select as}) {
300 delete @{$old_attrs}{qw{select as columns +select +as +columns include_columns}};
303 my $new_attrs = { %{$old_attrs}, %{$call_attrs} };
305 # merge new attrs into inherited
306 foreach my $key (qw/join prefetch +select +as +columns include_columns bind/) {
307 next unless exists $call_attrs->{$key};
308 $new_attrs->{$key} = $self->_merge_attr($old_attrs->{$key}, $call_attrs->{$key});
311 # rip apart the rest of @_, parse a condition
314 if (ref $_[0] eq 'HASH') {
315 (keys %{$_[0]}) ? $_[0] : undef
321 $self->throw_exception('Odd number of arguments to search')
329 for ($old_where, $call_cond) {
331 $new_attrs->{where} = $self->_stack_cond (
332 $_, $new_attrs->{where}
337 if (defined $old_having) {
338 $new_attrs->{having} = $self->_stack_cond (
339 $old_having, $new_attrs->{having}
343 my $rs = (ref $self)->new($self->result_source, $new_attrs);
345 $rs->set_cache($cache) if ($cache);
351 my ($self, $left, $right) = @_;
352 if (defined $left xor defined $right) {
353 return defined $left ? $left : $right;
355 elsif (defined $left) {
356 return { -and => [ map
357 { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
365 =head2 search_literal
369 =item Arguments: $sql_fragment, @bind_values
371 =item Return Value: $resultset (scalar context), @row_objs (list context)
375 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
376 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
378 Pass a literal chunk of SQL to be added to the conditional part of the
381 CAVEAT: C<search_literal> is provided for Class::DBI compatibility and should
382 only be used in that context. C<search_literal> is a convenience method.
383 It is equivalent to calling $schema->search(\[]), but if you want to ensure
384 columns are bound correctly, use C<search>.
386 Example of how to use C<search> instead of C<search_literal>
388 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
389 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
392 See L<DBIx::Class::Manual::Cookbook/Searching> and
393 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
394 require C<search_literal>.
399 my ($self, $sql, @bind) = @_;
401 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
404 return $self->search(\[ $sql, map [ __DUMMY__ => $_ ], @bind ], ($attr || () ));
411 =item Arguments: @values | \%cols, \%attrs?
413 =item Return Value: $row_object | undef
417 Finds a row based on its primary key or unique constraint. For example, to find
418 a row by its primary key:
420 my $cd = $schema->resultset('CD')->find(5);
422 You can also find a row by a specific unique constraint using the C<key>
423 attribute. For example:
425 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
426 key => 'cd_artist_title'
429 Additionally, you can specify the columns explicitly by name:
431 my $cd = $schema->resultset('CD')->find(
433 artist => 'Massive Attack',
434 title => 'Mezzanine',
436 { key => 'cd_artist_title' }
439 If the C<key> is specified as C<primary>, it searches only on the primary key.
441 If no C<key> is specified, it searches on all unique constraints defined on the
442 source for which column data is provided, including the primary key.
444 If your table does not have a primary key, you B<must> provide a value for the
445 C<key> attribute matching one of the unique constraints on the source.
447 In addition to C<key>, L</find> recognizes and applies standard
448 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
450 Note: If your query does not return only one row, a warning is generated:
452 Query returned more than one row
454 See also L</find_or_create> and L</update_or_create>. For information on how to
455 declare unique constraints, see
456 L<DBIx::Class::ResultSource/add_unique_constraint>.
462 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
464 # Parse out a query from input
466 if (ref $_[0] eq 'HASH') {
467 $input_query = { %{$_[0]} };
470 my $constraint = exists $attrs->{key} ? $attrs->{key} : 'primary';
471 my @c_cols = $self->result_source->unique_constraint_columns($constraint);
473 $self->throw_exception(
474 "No constraint columns, maybe a malformed '$constraint' constraint?"
477 $self->throw_exception (
478 'find() expects either a column/value hashref, or a list of values '
479 . "corresponding to the columns of the specified unique constraint '$constraint'"
480 ) unless @c_cols == @_;
483 @{$input_query}{@c_cols} = @_;
487 for my $key (keys %$input_query) {
489 my $keyref = ref($input_query->{$key})
491 my $relinfo = $self->result_source->relationship_info($key)
493 my $val = delete $input_query->{$key};
495 next if $keyref eq 'ARRAY'; # has_many for multi_create
497 my $rel_q = $self->result_source->_resolve_condition(
498 $relinfo->{cond}, $val, $key
500 die "Can't handle complex relationship conditions in find" if ref($rel_q) ne 'HASH';
501 @related{keys %$rel_q} = values %$rel_q;
505 # relationship conditions take precedence (?)
506 @{$input_query}{keys %related} = values %related;
508 # Build the final query: Default to the disjunction of the unique queries,
509 # but allow the input query in case the ResultSet defines the query or the
510 # user is abusing find
511 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
513 if (exists $attrs->{key}) {
514 my @unique_cols = $self->result_source->unique_constraint_columns($attrs->{key});
515 my $unique_query = $self->_build_unique_query($input_query, \@unique_cols);
516 $query = $self->_add_alias($unique_query, $alias);
518 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
519 # This means that we got here after a merger of relationship conditions
520 # in ::Relationship::Base::search_related (the row method), and furthermore
521 # the relationship is of the 'single' type. This means that the condition
522 # provided by the relationship (already attached to $self) is sufficient,
523 # as there can be only one row in the database that would satisfy the
527 # no key was specified - fall down to heuristics mode
528 # get all possible unique queries based on the combination of $query
529 # and the condition available in $self, and then run a search with
530 # each and every possible constraint (as long as it's completely specified)
531 my @unique_queries = $self->_unique_queries($input_query, $attrs);
532 $query = @unique_queries
533 ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
534 : $self->_add_alias($input_query, $alias);
537 # Run the query, passing the result_class since it should propagate for find
538 my $rs = $self->search ($query, {result_class => $self->result_class, %$attrs});
539 if (keys %{$rs->_resolved_attrs->{collapse}}) {
541 carp "Query returned more than one row" if $rs->next;
551 # Add the specified alias to the specified query hash. A copy is made so the
552 # original query is not modified.
555 my ($self, $query, $alias) = @_;
557 my %aliased = %$query;
558 foreach my $col (grep { ! m/\./ } keys %aliased) {
559 $aliased{"$alias.$col"} = delete $aliased{$col};
567 # Build a list of queries which satisfy the unique constraint(s) as per $attrs
569 sub _unique_queries {
570 my ($self, $query, $attrs) = @_;
572 my @constraint_names = exists $attrs->{key}
574 : $self->result_source->unique_constraint_names;
576 my $where = $self->_collapse_cond($self->{attrs}{where} || {});
577 my $num_where = scalar keys %$where;
579 my (@unique_queries, %seen_column_combinations);
580 foreach my $name (@constraint_names) {
581 my @constraint_cols = $self->result_source->unique_constraint_columns($name);
583 my $constraint_sig = join "\x00", sort @constraint_cols;
584 next if $seen_column_combinations{$constraint_sig}++;
586 my $unique_query = $self->_build_unique_query($query, \@constraint_cols);
588 my $num_cols = scalar @constraint_cols;
589 my $num_query = scalar keys %$unique_query;
591 my $total = $num_query + $num_where;
592 if ($num_query && ($num_query == $num_cols || $total == $num_cols)) {
593 # The query is either unique on its own or is unique in combination with
594 # the existing where clause
595 push @unique_queries, $unique_query;
599 return @unique_queries;
602 # _build_unique_query
604 # Constrain the specified query hash based on the specified column names.
606 sub _build_unique_query {
607 my ($self, $query, $unique_cols) = @_;
610 map { $_ => $query->{$_} }
611 grep { exists $query->{$_} }
616 =head2 search_related
620 =item Arguments: $rel, $cond, \%attrs?
622 =item Return Value: $new_resultset
626 $new_rs = $cd_rs->search_related('artist', {
630 Searches the specified relationship, optionally specifying a condition and
631 attributes for matching records. See L</ATTRIBUTES> for more information.
636 return shift->related_resultset(shift)->search(@_);
639 =head2 search_related_rs
641 This method works exactly the same as search_related, except that
642 it guarantees a resultset, even in list context.
646 sub search_related_rs {
647 return shift->related_resultset(shift)->search_rs(@_);
654 =item Arguments: none
656 =item Return Value: $cursor
660 Returns a storage-driven cursor to the given resultset. See
661 L<DBIx::Class::Cursor> for more information.
668 my $attrs = $self->_resolved_attrs_copy;
670 return $self->{cursor}
671 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
672 $attrs->{where},$attrs);
679 =item Arguments: $cond?
681 =item Return Value: $row_object | undef
685 my $cd = $schema->resultset('CD')->single({ year => 2001 });
687 Inflates the first result without creating a cursor if the resultset has
688 any records in it; if not returns C<undef>. Used by L</find> as a lean version
691 While this method can take an optional search condition (just like L</search>)
692 being a fast-code-path it does not recognize search attributes. If you need to
693 add extra joins or similar, call L</search> and then chain-call L</single> on the
694 L<DBIx::Class::ResultSet> returned.
700 As of 0.08100, this method enforces the assumption that the preceding
701 query returns only one row. If more than one row is returned, you will receive
704 Query returned more than one row
706 In this case, you should be using L</next> or L</find> instead, or if you really
707 know what you are doing, use the L</rows> attribute to explicitly limit the size
710 This method will also throw an exception if it is called on a resultset prefetching
711 has_many, as such a prefetch implies fetching multiple rows from the database in
712 order to assemble the resulting object.
719 my ($self, $where) = @_;
721 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
724 my $attrs = $self->_resolved_attrs_copy;
726 if (keys %{$attrs->{collapse}}) {
727 $self->throw_exception(
728 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
733 if (defined $attrs->{where}) {
736 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
737 $where, delete $attrs->{where} ]
740 $attrs->{where} = $where;
744 my @data = $self->result_source->storage->select_single(
745 $attrs->{from}, $attrs->{select},
746 $attrs->{where}, $attrs
749 return (@data ? ($self->_construct_object(@data))[0] : undef);
755 # Recursively collapse the query, accumulating values for each column.
757 sub _collapse_query {
758 my ($self, $query, $collapsed) = @_;
762 if (ref $query eq 'ARRAY') {
763 foreach my $subquery (@$query) {
764 next unless ref $subquery; # -or
765 $collapsed = $self->_collapse_query($subquery, $collapsed);
768 elsif (ref $query eq 'HASH') {
769 if (keys %$query and (keys %$query)[0] eq '-and') {
770 foreach my $subquery (@{$query->{-and}}) {
771 $collapsed = $self->_collapse_query($subquery, $collapsed);
775 foreach my $col (keys %$query) {
776 my $value = $query->{$col};
777 $collapsed->{$col}{$value}++;
789 =item Arguments: $cond?
791 =item Return Value: $resultsetcolumn
795 my $max_length = $rs->get_column('length')->max;
797 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
802 my ($self, $column) = @_;
803 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
811 =item Arguments: $cond, \%attrs?
813 =item Return Value: $resultset (scalar context), @row_objs (list context)
817 # WHERE title LIKE '%blue%'
818 $cd_rs = $rs->search_like({ title => '%blue%'});
820 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
821 that this is simply a convenience method retained for ex Class::DBI users.
822 You most likely want to use L</search> with specific operators.
824 For more information, see L<DBIx::Class::Manual::Cookbook>.
826 This method is deprecated and will be removed in 0.09. Use L</search()>
827 instead. An example conversion is:
829 ->search_like({ foo => 'bar' });
833 ->search({ foo => { like => 'bar' } });
840 'search_like() is deprecated and will be removed in DBIC version 0.09.'
841 .' Instead use ->search({ x => { -like => "y%" } })'
842 .' (note the outer pair of {}s - they are important!)'
844 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
845 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
846 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
847 return $class->search($query, { %$attrs });
854 =item Arguments: $first, $last
856 =item Return Value: $resultset (scalar context), @row_objs (list context)
860 Returns a resultset or object list representing a subset of elements from the
861 resultset slice is called on. Indexes are from 0, i.e., to get the first
864 my ($one, $two, $three) = $rs->slice(0, 2);
869 my ($self, $min, $max) = @_;
870 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
871 $attrs->{offset} = $self->{attrs}{offset} || 0;
872 $attrs->{offset} += $min;
873 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
874 return $self->search(undef, $attrs);
875 #my $slice = (ref $self)->new($self->result_source, $attrs);
876 #return (wantarray ? $slice->all : $slice);
883 =item Arguments: none
885 =item Return Value: $result | undef
889 Returns the next element in the resultset (C<undef> is there is none).
891 Can be used to efficiently iterate over records in the resultset:
893 my $rs = $schema->resultset('CD')->search;
894 while (my $cd = $rs->next) {
898 Note that you need to store the resultset object, and call C<next> on it.
899 Calling C<< resultset('Table')->next >> repeatedly will always return the
900 first record from the resultset.
906 if (my $cache = $self->get_cache) {
907 $self->{all_cache_position} ||= 0;
908 return $cache->[$self->{all_cache_position}++];
910 if ($self->{attrs}{cache}) {
911 delete $self->{pager};
912 $self->{all_cache_position} = 1;
913 return ($self->all)[0];
915 if ($self->{stashed_objects}) {
916 my $obj = shift(@{$self->{stashed_objects}});
917 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
921 exists $self->{stashed_row}
922 ? @{delete $self->{stashed_row}}
923 : $self->cursor->next
925 return undef unless (@row);
926 my ($row, @more) = $self->_construct_object(@row);
927 $self->{stashed_objects} = \@more if @more;
931 sub _construct_object {
932 my ($self, @row) = @_;
934 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row)
936 my @new = $self->result_class->inflate_result($self->result_source, @$info);
937 @new = $self->{_attrs}{record_filter}->(@new)
938 if exists $self->{_attrs}{record_filter};
942 sub _collapse_result {
943 my ($self, $as_proto, $row) = @_;
947 # 'foo' => [ undef, 'foo' ]
948 # 'foo.bar' => [ 'foo', 'bar' ]
949 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
951 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
953 my %collapse = %{$self->{_attrs}{collapse}||{}};
957 # if we're doing collapsing (has_many prefetch) we need to grab records
958 # until the PK changes, so fill @pri_index. if not, we leave it empty so
959 # we know we don't have to bother.
961 # the reason for not using the collapse stuff directly is because if you
962 # had for e.g. two artists in a row with no cds, the collapse info for
963 # both would be NULL (undef) so you'd lose the second artist
965 # store just the index so we can check the array positions from the row
966 # without having to contruct the full hash
968 if (keys %collapse) {
969 my %pri = map { ($_ => 1) } $self->result_source->_pri_cols;
970 foreach my $i (0 .. $#construct_as) {
971 next if defined($construct_as[$i][0]); # only self table
972 if (delete $pri{$construct_as[$i][1]}) {
973 push(@pri_index, $i);
975 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
979 # no need to do an if, it'll be empty if @pri_index is empty anyway
981 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
985 do { # no need to check anything at the front, we always want the first row
989 foreach my $this_as (@construct_as) {
990 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
993 push(@const_rows, \%const);
995 } until ( # no pri_index => no collapse => drop straight out
998 do { # get another row, stash it, drop out if different PK
1000 @copy = $self->cursor->next;
1001 $self->{stashed_row} = \@copy;
1003 # last thing in do block, counts as true if anything doesn't match
1005 # check xor defined first for NULL vs. NOT NULL then if one is
1006 # defined the other must be so check string equality
1009 (defined $pri_vals{$_} ^ defined $copy[$_])
1010 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
1015 my $alias = $self->{attrs}{alias};
1022 foreach my $const (@const_rows) {
1023 scalar @const_keys or do {
1024 @const_keys = sort { length($a) <=> length($b) } keys %$const;
1026 foreach my $key (@const_keys) {
1029 my @parts = split(/\./, $key);
1031 my $data = $const->{$key};
1032 foreach my $p (@parts) {
1033 $target = $target->[1]->{$p} ||= [];
1035 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
1036 # collapsing at this point and on final part
1037 my $pos = $collapse_pos{$cur};
1038 CK: foreach my $ck (@ckey) {
1039 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
1040 $collapse_pos{$cur} = $data;
1041 delete @collapse_pos{ # clear all positioning for sub-entries
1042 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
1049 if (exists $collapse{$cur}) {
1050 $target = $target->[-1];
1053 $target->[0] = $data;
1055 $info->[0] = $const->{$key};
1063 =head2 result_source
1067 =item Arguments: $result_source?
1069 =item Return Value: $result_source
1073 An accessor for the primary ResultSource object from which this ResultSet
1080 =item Arguments: $result_class?
1082 =item Return Value: $result_class
1086 An accessor for the class to use when creating row objects. Defaults to
1087 C<< result_source->result_class >> - which in most cases is the name of the
1088 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1090 Note that changing the result_class will also remove any components
1091 that were originally loaded in the source class via
1092 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1093 in the original source class will not run.
1098 my ($self, $result_class) = @_;
1099 if ($result_class) {
1100 unless (ref $result_class) { # don't fire this for an object
1101 $self->ensure_class_loaded($result_class);
1103 $self->_result_class($result_class);
1104 # THIS LINE WOULD BE A BUG - this accessor specifically exists to
1105 # permit the user to set result class on one result set only; it only
1106 # chains if provided to search()
1107 #$self->{attrs}{result_class} = $result_class if ref $self;
1109 $self->_result_class;
1116 =item Arguments: $cond, \%attrs??
1118 =item Return Value: $count
1122 Performs an SQL C<COUNT> with the same query as the resultset was built
1123 with to find the number of elements. Passing arguments is equivalent to
1124 C<< $rs->search ($cond, \%attrs)->count >>
1130 return $self->search(@_)->count if @_ and defined $_[0];
1131 return scalar @{ $self->get_cache } if $self->get_cache;
1133 my $attrs = $self->_resolved_attrs_copy;
1135 # this is a little optimization - it is faster to do the limit
1136 # adjustments in software, instead of a subquery
1137 my $rows = delete $attrs->{rows};
1138 my $offset = delete $attrs->{offset};
1141 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1142 $crs = $self->_count_subq_rs ($attrs);
1145 $crs = $self->_count_rs ($attrs);
1147 my $count = $crs->next;
1149 $count -= $offset if $offset;
1150 $count = $rows if $rows and $rows < $count;
1151 $count = 0 if ($count < 0);
1160 =item Arguments: $cond, \%attrs??
1162 =item Return Value: $count_rs
1166 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1167 This can be very handy for subqueries:
1169 ->search( { amount => $some_rs->count_rs->as_query } )
1171 As with regular resultsets the SQL query will be executed only after
1172 the resultset is accessed via L</next> or L</all>. That would return
1173 the same single value obtainable via L</count>.
1179 return $self->search(@_)->count_rs if @_;
1181 # this may look like a lack of abstraction (count() does about the same)
1182 # but in fact an _rs *must* use a subquery for the limits, as the
1183 # software based limiting can not be ported if this $rs is to be used
1184 # in a subquery itself (i.e. ->as_query)
1185 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1186 return $self->_count_subq_rs;
1189 return $self->_count_rs;
1194 # returns a ResultSetColumn object tied to the count query
1197 my ($self, $attrs) = @_;
1199 my $rsrc = $self->result_source;
1200 $attrs ||= $self->_resolved_attrs;
1202 my $tmp_attrs = { %$attrs };
1203 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1204 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1206 # overwrite the selector (supplied by the storage)
1207 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $attrs);
1208 $tmp_attrs->{as} = 'count';
1210 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1216 # same as above but uses a subquery
1218 sub _count_subq_rs {
1219 my ($self, $attrs) = @_;
1221 my $rsrc = $self->result_source;
1222 $attrs ||= $self->_resolved_attrs;
1224 my $sub_attrs = { %$attrs };
1225 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1226 delete @{$sub_attrs}{qw/collapse select _prefetch_select as order_by for/};
1228 # if we multi-prefetch we group_by primary keys only as this is what we would
1229 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1230 if ( keys %{$attrs->{collapse}} ) {
1231 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } ($rsrc->_pri_cols) ]
1234 # Calculate subquery selector
1235 if (my $g = $sub_attrs->{group_by}) {
1237 my $sql_maker = $rsrc->storage->sql_maker;
1239 # necessary as the group_by may refer to aliased functions
1241 for my $sel (@{$attrs->{select}}) {
1242 $sel_index->{$sel->{-as}} = $sel
1243 if (ref $sel eq 'HASH' and $sel->{-as});
1246 for my $g_part (@$g) {
1247 my $colpiece = $sel_index->{$g_part} || $g_part;
1249 # disqualify join-based group_by's. Arcane but possible query
1250 # also horrible horrible hack to alias a column (not a func.)
1251 # (probably need to introduce SQLA syntax)
1252 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1255 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1257 push @{$sub_attrs->{select}}, $colpiece;
1261 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1262 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1265 return $rsrc->resultset_class
1266 ->new ($rsrc, $sub_attrs)
1268 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1269 ->get_column ('count');
1276 =head2 count_literal
1280 =item Arguments: $sql_fragment, @bind_values
1282 =item Return Value: $count
1286 Counts the results in a literal query. Equivalent to calling L</search_literal>
1287 with the passed arguments, then L</count>.
1291 sub count_literal { shift->search_literal(@_)->count; }
1297 =item Arguments: none
1299 =item Return Value: @objects
1303 Returns all elements in the resultset. Called implicitly if the resultset
1304 is returned in list context.
1311 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1314 return @{ $self->get_cache } if $self->get_cache;
1318 if (keys %{$self->_resolved_attrs->{collapse}}) {
1319 # Using $self->cursor->all is really just an optimisation.
1320 # If we're collapsing has_many prefetches it probably makes
1321 # very little difference, and this is cleaner than hacking
1322 # _construct_object to survive the approach
1323 $self->cursor->reset;
1324 my @row = $self->cursor->next;
1326 push(@obj, $self->_construct_object(@row));
1327 @row = (exists $self->{stashed_row}
1328 ? @{delete $self->{stashed_row}}
1329 : $self->cursor->next);
1332 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1335 $self->set_cache(\@obj) if $self->{attrs}{cache};
1344 =item Arguments: none
1346 =item Return Value: $self
1350 Resets the resultset's cursor, so you can iterate through the elements again.
1351 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1358 delete $self->{_attrs} if exists $self->{_attrs};
1359 $self->{all_cache_position} = 0;
1360 $self->cursor->reset;
1368 =item Arguments: none
1370 =item Return Value: $object | undef
1374 Resets the resultset and returns an object for the first result (or C<undef>
1375 if the resultset is empty).
1380 return $_[0]->reset->next;
1386 # Determines whether and what type of subquery is required for the $rs operation.
1387 # If grouping is necessary either supplies its own, or verifies the current one
1388 # After all is done delegates to the proper storage method.
1390 sub _rs_update_delete {
1391 my ($self, $op, $values) = @_;
1393 my $rsrc = $self->result_source;
1395 # if a condition exists we need to strip all table qualifiers
1396 # if this is not possible we'll force a subquery below
1397 my $cond = $rsrc->schema->storage->_strip_cond_qualifiers ($self->{cond});
1399 my $needs_group_by_subq = $self->_has_resolved_attr (qw/collapse group_by -join/);
1400 my $needs_subq = $needs_group_by_subq || (not defined $cond) || $self->_has_resolved_attr(qw/rows offset/);
1402 if ($needs_group_by_subq or $needs_subq) {
1404 # make a new $rs selecting only the PKs (that's all we really need)
1405 my $attrs = $self->_resolved_attrs_copy;
1408 delete $attrs->{$_} for qw/collapse _collapse_order_by select _prefetch_select as/;
1409 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->_pri_cols) ];
1411 if ($needs_group_by_subq) {
1412 # make sure no group_by was supplied, or if there is one - make sure it matches
1413 # the columns compiled above perfectly. Anything else can not be sanely executed
1414 # on most databases so croak right then and there
1416 if (my $g = $attrs->{group_by}) {
1417 my @current_group_by = map
1418 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1423 join ("\x00", sort @current_group_by)
1425 join ("\x00", sort @{$attrs->{columns}} )
1427 $self->throw_exception (
1428 "You have just attempted a $op operation on a resultset which does group_by"
1429 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1430 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1431 . ' kind of queries. Please retry the operation with a modified group_by or'
1432 . ' without using one at all.'
1437 $attrs->{group_by} = $attrs->{columns};
1441 my $subrs = (ref $self)->new($rsrc, $attrs);
1442 return $self->result_source->storage->_subq_update_delete($subrs, $op, $values);
1445 return $rsrc->storage->$op(
1447 $op eq 'update' ? $values : (),
1457 =item Arguments: \%values
1459 =item Return Value: $storage_rv
1463 Sets the specified columns in the resultset to the supplied values in a
1464 single query. Note that this will not run any accessor/set_column/update
1465 triggers, nor will it update any row object instances derived from this
1466 resultset (this includes the contents of the L<resultset cache|/set_cache>
1467 if any). See L</update_all> if you need to execute any on-update
1468 triggers or cascades defined either by you or a
1469 L<result component|DBIx::Class::Manual::Component/WHAT_IS_A_COMPONENT>.
1471 The return value is a pass through of what the underlying
1472 storage backend returned, and may vary. See L<DBI/execute> for the most
1478 my ($self, $values) = @_;
1479 $self->throw_exception('Values for update must be a hash')
1480 unless ref $values eq 'HASH';
1482 return $self->_rs_update_delete ('update', $values);
1489 =item Arguments: \%values
1491 =item Return Value: 1
1495 Fetches all objects and updates them one at a time via
1496 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
1497 triggers, while L</update> will not.
1502 my ($self, $values) = @_;
1503 $self->throw_exception('Values for update_all must be a hash')
1504 unless ref $values eq 'HASH';
1506 my $guard = $self->result_source->schema->txn_scope_guard;
1507 $_->update($values) for $self->all;
1516 =item Arguments: none
1518 =item Return Value: $storage_rv
1522 Deletes the rows matching this resultset in a single query. Note that this
1523 will not run any delete triggers, nor will it alter the
1524 L<in_storage|DBIx::Class::Row/in_storage> status of any row object instances
1525 derived from this resultset (this includes the contents of the
1526 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
1527 execute any on-delete triggers or cascades defined either by you or a
1528 L<result component|DBIx::Class::Manual::Component/WHAT_IS_A_COMPONENT>.
1530 The return value is a pass through of what the underlying storage backend
1531 returned, and may vary. See L<DBI/execute> for the most common case.
1537 $self->throw_exception('delete does not accept any arguments')
1540 return $self->_rs_update_delete ('delete');
1547 =item Arguments: none
1549 =item Return Value: 1
1553 Fetches all objects and deletes them one at a time via
1554 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
1555 triggers, while L</delete> will not.
1561 $self->throw_exception('delete_all does not accept any arguments')
1564 my $guard = $self->result_source->schema->txn_scope_guard;
1565 $_->delete for $self->all;
1574 =item Arguments: \@data;
1578 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1579 For the arrayref of hashrefs style each hashref should be a structure suitable
1580 forsubmitting to a $resultset->create(...) method.
1582 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1583 to insert the data, as this is a faster method.
1585 Otherwise, each set of data is inserted into the database using
1586 L<DBIx::Class::ResultSet/create>, and the resulting objects are
1587 accumulated into an array. The array itself, or an array reference
1588 is returned depending on scalar or list context.
1590 Example: Assuming an Artist Class that has many CDs Classes relating:
1592 my $Artist_rs = $schema->resultset("Artist");
1594 ## Void Context Example
1595 $Artist_rs->populate([
1596 { artistid => 4, name => 'Manufactured Crap', cds => [
1597 { title => 'My First CD', year => 2006 },
1598 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1601 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1602 { title => 'My parents sold me to a record company', year => 2005 },
1603 { title => 'Why Am I So Ugly?', year => 2006 },
1604 { title => 'I Got Surgery and am now Popular', year => 2007 }
1609 ## Array Context Example
1610 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1611 { name => "Artist One"},
1612 { name => "Artist Two"},
1613 { name => "Artist Three", cds=> [
1614 { title => "First CD", year => 2007},
1615 { title => "Second CD", year => 2008},
1619 print $ArtistOne->name; ## response is 'Artist One'
1620 print $ArtistThree->cds->count ## reponse is '2'
1622 For the arrayref of arrayrefs style, the first element should be a list of the
1623 fieldsnames to which the remaining elements are rows being inserted. For
1626 $Arstist_rs->populate([
1627 [qw/artistid name/],
1628 [100, 'A Formally Unknown Singer'],
1629 [101, 'A singer that jumped the shark two albums ago'],
1630 [102, 'An actually cool singer'],
1633 Please note an important effect on your data when choosing between void and
1634 wantarray context. Since void context goes straight to C<insert_bulk> in
1635 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
1636 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
1637 create primary keys for you, you will find that your PKs are empty. In this
1638 case you will have to use the wantarray context in order to create those
1646 # cruft placed in standalone method
1647 my $data = $self->_normalize_populate_args(@_);
1649 if(defined wantarray) {
1651 foreach my $item (@$data) {
1652 push(@created, $self->create($item));
1654 return wantarray ? @created : \@created;
1656 my $first = $data->[0];
1658 # if a column is a registered relationship, and is a non-blessed hash/array, consider
1659 # it relationship data
1660 my (@rels, @columns);
1661 for (keys %$first) {
1662 my $ref = ref $first->{$_};
1663 $self->result_source->has_relationship($_) && ($ref eq 'ARRAY' or $ref eq 'HASH')
1669 my @pks = $self->result_source->primary_columns;
1671 ## do the belongs_to relationships
1672 foreach my $index (0..$#$data) {
1674 # delegate to create() for any dataset without primary keys with specified relationships
1675 if (grep { !defined $data->[$index]->{$_} } @pks ) {
1677 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
1678 my @ret = $self->populate($data);
1684 foreach my $rel (@rels) {
1685 next unless ref $data->[$index]->{$rel} eq "HASH";
1686 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1687 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1688 my $related = $result->result_source->_resolve_condition(
1689 $result->result_source->relationship_info($reverse)->{cond},
1694 delete $data->[$index]->{$rel};
1695 $data->[$index] = {%{$data->[$index]}, %$related};
1697 push @columns, keys %$related if $index == 0;
1701 ## inherit the data locked in the conditions of the resultset
1702 my ($rs_data) = $self->_merge_cond_with_data({});
1703 delete @{$rs_data}{@columns};
1704 my @inherit_cols = keys %$rs_data;
1705 my @inherit_data = values %$rs_data;
1707 ## do bulk insert on current row
1708 $self->result_source->storage->insert_bulk(
1709 $self->result_source,
1710 [@columns, @inherit_cols],
1711 [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
1714 ## do the has_many relationships
1715 foreach my $item (@$data) {
1717 foreach my $rel (@rels) {
1718 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1720 my $parent = $self->find({map { $_ => $item->{$_} } @pks})
1721 || $self->throw_exception('Cannot find the relating object.');
1723 my $child = $parent->$rel;
1725 my $related = $child->result_source->_resolve_condition(
1726 $parent->result_source->relationship_info($rel)->{cond},
1731 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1732 my @populate = map { {%$_, %$related} } @rows_to_add;
1734 $child->populate( \@populate );
1741 # populate() argumnets went over several incarnations
1742 # What we ultimately support is AoH
1743 sub _normalize_populate_args {
1744 my ($self, $arg) = @_;
1746 if (ref $arg eq 'ARRAY') {
1747 if (ref $arg->[0] eq 'HASH') {
1750 elsif (ref $arg->[0] eq 'ARRAY') {
1752 my @colnames = @{$arg->[0]};
1753 foreach my $values (@{$arg}[1 .. $#$arg]) {
1754 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
1760 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
1767 =item Arguments: none
1769 =item Return Value: $pager
1773 Return Value a L<Data::Page> object for the current resultset. Only makes
1774 sense for queries with a C<page> attribute.
1776 To get the full count of entries for a paged resultset, call
1777 C<total_entries> on the L<Data::Page> object.
1781 # make a wizard good for both a scalar and a hashref
1782 my $mk_lazy_count_wizard = sub {
1783 require Variable::Magic;
1785 my $stash = { total_rs => shift };
1786 my $slot = shift; # only used by the hashref magic
1788 my $magic = Variable::Magic::wizard (
1789 data => sub { $stash },
1795 # set value lazily, and dispell for good
1796 ${$_[0]} = $_[1]{total_rs}->count;
1797 Variable::Magic::dispell (${$_[0]}, $_[1]{magic_selfref});
1801 # an explicit set implies dispell as well
1802 # the unless() is to work around "fun and giggles" below
1803 Variable::Magic::dispell (${$_[0]}, $_[1]{magic_selfref})
1804 unless (caller(2))[3] eq 'DBIx::Class::ResultSet::pager';
1811 if ($_[2] eq $slot and !$_[1]{inactive}) {
1812 my $cnt = $_[1]{total_rs}->count;
1813 $_[0]->{$slot} = $cnt;
1815 # attempting to dispell in a fetch handle (works in store), seems
1816 # to invariable segfault on 5.10, 5.12, 5.13 :(
1817 # so use an inactivator instead
1818 #Variable::Magic::dispell (%{$_[0]}, $_[1]{magic_selfref});
1824 if (! $_[1]{inactive} and $_[2] eq $slot) {
1825 #Variable::Magic::dispell (%{$_[0]}, $_[1]{magic_selfref});
1827 unless (caller(2))[3] eq 'DBIx::Class::ResultSet::pager';
1834 $stash->{magic_selfref} = $magic;
1835 weaken ($stash->{magic_selfref}); # this fails on 5.8.1
1840 # the tie class for 5.8.1
1842 package DBIx::Class::__DBIC_LAZY_RS_COUNT__;
1843 use base qw/Tie::Hash/;
1845 sub FIRSTKEY { my $dummy = scalar keys %{$_[0]{data}}; each %{$_[0]{data}} }
1846 sub NEXTKEY { each %{$_[0]{data}} }
1847 sub EXISTS { exists $_[0]{data}{$_[1]} }
1848 sub DELETE { delete $_[0]{data}{$_[1]} }
1849 sub CLEAR { %{$_[0]{data}} = () }
1850 sub SCALAR { scalar %{$_[0]{data}} }
1853 $_[1]{data} = {%{$_[1]{selfref}}};
1854 %{$_[1]{selfref}} = ();
1855 Scalar::Util::weaken ($_[1]{selfref});
1856 return bless ($_[1], $_[0]);
1860 if ($_[1] eq $_[0]{slot}) {
1861 my $cnt = $_[0]{data}{$_[1]} = $_[0]{total_rs}->count;
1862 untie %{$_[0]{selfref}};
1863 %{$_[0]{selfref}} = %{$_[0]{data}};
1872 $_[0]{data}{$_[1]} = $_[2];
1873 if ($_[1] eq $_[0]{slot}) {
1874 untie %{$_[0]{selfref}};
1875 %{$_[0]{selfref}} = %{$_[0]{data}};
1884 return $self->{pager} if $self->{pager};
1886 if ($self->get_cache) {
1887 $self->throw_exception ('Pagers on cached resultsets are not supported');
1890 my $attrs = $self->{attrs};
1891 $self->throw_exception("Can't create pager for non-paged rs")
1892 unless $self->{attrs}{page};
1893 $attrs->{rows} ||= 10;
1895 # throw away the paging flags and re-run the count (possibly
1896 # with a subselect) to get the real total count
1897 my $count_attrs = { %$attrs };
1898 delete $count_attrs->{$_} for qw/rows offset page pager/;
1899 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
1902 ### the following may seem awkward and dirty, but it's a thought-experiment
1903 ### necessary for future development of DBIx::DS. Do *NOT* change this code
1904 ### before talking to ribasushi/mst
1906 my $pager = Data::Page->new(
1907 0, #start with an empty set
1909 $self->{attrs}{page},
1912 my $data_slot = 'total_entries';
1914 # Since we are interested in a cached value (once it's set - it's set), every
1915 # technique will detach from the magic-host once the time comes to fire the
1916 # ->count (or in the segfaulting case of >= 5.10 it will deactivate itself)
1918 if ($] < 5.008003) {
1919 # 5.8.1 throws 'Modification of a read-only value attempted' when one tries
1920 # to weakref the magic container :(
1922 tie (%$pager, 'DBIx::Class::__DBIC_LAZY_RS_COUNT__',
1923 { slot => $data_slot, total_rs => $total_rs, selfref => $pager }
1926 elsif ($] < 5.010) {
1927 # We can use magic on the hash value slot. It's interesting that the magic is
1928 # attached to the hash-slot, and does *not* stop working once I do the dummy
1929 # assignments after the cast()
1930 # tested on 5.8.3 and 5.8.9
1931 my $magic = $mk_lazy_count_wizard->($total_rs);
1932 Variable::Magic::cast ( $pager->{$data_slot}, $magic );
1934 # this is for fun and giggles
1935 $pager->{$data_slot} = -1;
1936 $pager->{$data_slot} = 0;
1938 # this does not work for scalars, but works with
1940 #my %vals = %$pager;
1945 # And the uvar magic
1946 # works on 5.10.1, 5.12.1 and 5.13.4 in its current form,
1947 # however see the wizard maker for more notes
1948 my $magic = $mk_lazy_count_wizard->($total_rs, $data_slot);
1949 Variable::Magic::cast ( %$pager, $magic );
1952 $pager->{$data_slot} = -1;
1953 $pager->{$data_slot} = 0;
1961 return $self->{pager} = $pager;
1968 =item Arguments: $page_number
1970 =item Return Value: $rs
1974 Returns a resultset for the $page_number page of the resultset on which page
1975 is called, where each page contains a number of rows equal to the 'rows'
1976 attribute set on the resultset (10 by default).
1981 my ($self, $page) = @_;
1982 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1989 =item Arguments: \%vals
1991 =item Return Value: $rowobject
1995 Creates a new row object in the resultset's result class and returns
1996 it. The row is not inserted into the database at this point, call
1997 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
1998 will tell you whether the row object has been inserted or not.
2000 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2005 my ($self, $values) = @_;
2006 $self->throw_exception( "new_result needs a hash" )
2007 unless (ref $values eq 'HASH');
2009 my ($merged_cond, $cols_from_relations) = $self->_merge_cond_with_data($values);
2013 @$cols_from_relations
2014 ? (-cols_from_relations => $cols_from_relations)
2016 -source_handle => $self->_source_handle,
2017 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2020 return $self->result_class->new(\%new);
2023 # _merge_cond_with_data
2025 # Takes a simple hash of K/V data and returns its copy merged with the
2026 # condition already present on the resultset. Additionally returns an
2027 # arrayref of value/condition names, which were inferred from related
2028 # objects (this is needed for in-memory related objects)
2029 sub _merge_cond_with_data {
2030 my ($self, $data) = @_;
2032 my (%new_data, @cols_from_relations);
2034 my $alias = $self->{attrs}{alias};
2036 if (! defined $self->{cond}) {
2037 # just massage $data below
2039 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
2040 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
2041 @cols_from_relations = keys %new_data;
2043 elsif (ref $self->{cond} ne 'HASH') {
2044 $self->throw_exception(
2045 "Can't abstract implicit construct, resultset condition not a hash"
2049 # precendence must be given to passed values over values inherited from
2050 # the cond, so the order here is important.
2051 my $collapsed_cond = $self->_collapse_cond($self->{cond});
2052 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
2054 while ( my($col, $value) = each %implied ) {
2055 if (ref($value) eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '=') {
2056 $new_data{$col} = $value->{'='};
2059 $new_data{$col} = $value if $self->_is_deterministic_value($value);
2065 %{ $self->_remove_alias($data, $alias) },
2068 return (\%new_data, \@cols_from_relations);
2071 # _is_deterministic_value
2073 # Make an effor to strip non-deterministic values from the condition,
2074 # to make sure new_result chokes less
2076 sub _is_deterministic_value {
2079 my $ref_type = ref $value;
2080 return 1 if $ref_type eq '' || $ref_type eq 'SCALAR';
2081 return 1 if blessed $value;
2085 # _has_resolved_attr
2087 # determines if the resultset defines at least one
2088 # of the attributes supplied
2090 # used to determine if a subquery is neccessary
2092 # supports some virtual attributes:
2094 # This will scan for any joins being present on the resultset.
2095 # It is not a mere key-search but a deep inspection of {from}
2098 sub _has_resolved_attr {
2099 my ($self, @attr_names) = @_;
2101 my $attrs = $self->_resolved_attrs;
2105 for my $n (@attr_names) {
2106 if (grep { $n eq $_ } (qw/-join/) ) {
2107 $extra_checks{$n}++;
2111 my $attr = $attrs->{$n};
2113 next if not defined $attr;
2115 if (ref $attr eq 'HASH') {
2116 return 1 if keys %$attr;
2118 elsif (ref $attr eq 'ARRAY') {
2126 # a resolved join is expressed as a multi-level from
2128 $extra_checks{-join}
2130 ref $attrs->{from} eq 'ARRAY'
2132 @{$attrs->{from}} > 1
2140 # Recursively collapse the condition.
2142 sub _collapse_cond {
2143 my ($self, $cond, $collapsed) = @_;
2147 if (ref $cond eq 'ARRAY') {
2148 foreach my $subcond (@$cond) {
2149 next unless ref $subcond; # -or
2150 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2153 elsif (ref $cond eq 'HASH') {
2154 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2155 foreach my $subcond (@{$cond->{-and}}) {
2156 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2160 foreach my $col (keys %$cond) {
2161 my $value = $cond->{$col};
2162 $collapsed->{$col} = $value;
2172 # Remove the specified alias from the specified query hash. A copy is made so
2173 # the original query is not modified.
2176 my ($self, $query, $alias) = @_;
2178 my %orig = %{ $query || {} };
2181 foreach my $key (keys %orig) {
2183 $unaliased{$key} = $orig{$key};
2186 $unaliased{$1} = $orig{$key}
2187 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2197 =item Arguments: none
2199 =item Return Value: \[ $sql, @bind ]
2203 Returns the SQL query and bind vars associated with the invocant.
2205 This is generally used as the RHS for a subquery.
2212 my $attrs = $self->_resolved_attrs_copy;
2217 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2218 # $sql also has no wrapping parenthesis in list ctx
2220 my $sqlbind = $self->result_source->storage
2221 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2230 =item Arguments: \%vals, \%attrs?
2232 =item Return Value: $rowobject
2236 my $artist = $schema->resultset('Artist')->find_or_new(
2237 { artist => 'fred' }, { key => 'artists' });
2239 $cd->cd_to_producer->find_or_new({ producer => $producer },
2240 { key => 'primary });
2242 Find an existing record from this resultset, based on its primary
2243 key, or a unique constraint. If none exists, instantiate a new result
2244 object and return it. The object will not be saved into your storage
2245 until you call L<DBIx::Class::Row/insert> on it.
2247 You most likely want this method when looking for existing rows using
2248 a unique constraint that is not the primary key, or looking for
2251 If you want objects to be saved immediately, use L</find_or_create>
2254 B<Note>: Take care when using C<find_or_new> with a table having
2255 columns with default values that you intend to be automatically
2256 supplied by the database (e.g. an auto_increment primary key column).
2257 In normal usage, the value of such columns should NOT be included at
2258 all in the call to C<find_or_new>, even when set to C<undef>.
2264 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2265 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2266 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2269 return $self->new_result($hash);
2276 =item Arguments: \%vals
2278 =item Return Value: a L<DBIx::Class::Row> $object
2282 Attempt to create a single new row or a row with multiple related rows
2283 in the table represented by the resultset (and related tables). This
2284 will not check for duplicate rows before inserting, use
2285 L</find_or_create> to do that.
2287 To create one row for this resultset, pass a hashref of key/value
2288 pairs representing the columns of the table and the values you wish to
2289 store. If the appropriate relationships are set up, foreign key fields
2290 can also be passed an object representing the foreign row, and the
2291 value will be set to its primary key.
2293 To create related objects, pass a hashref of related-object column values
2294 B<keyed on the relationship name>. If the relationship is of type C<multi>
2295 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2296 The process will correctly identify columns holding foreign keys, and will
2297 transparently populate them from the keys of the corresponding relation.
2298 This can be applied recursively, and will work correctly for a structure
2299 with an arbitrary depth and width, as long as the relationships actually
2300 exists and the correct column data has been supplied.
2303 Instead of hashrefs of plain related data (key/value pairs), you may
2304 also pass new or inserted objects. New objects (not inserted yet, see
2305 L</new>), will be inserted into their appropriate tables.
2307 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2309 Example of creating a new row.
2311 $person_rs->create({
2312 name=>"Some Person",
2313 email=>"somebody@someplace.com"
2316 Example of creating a new row and also creating rows in a related C<has_many>
2317 or C<has_one> resultset. Note Arrayref.
2320 { artistid => 4, name => 'Manufactured Crap', cds => [
2321 { title => 'My First CD', year => 2006 },
2322 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2327 Example of creating a new row and also creating a row in a related
2328 C<belongs_to> resultset. Note Hashref.
2331 title=>"Music for Silly Walks",
2334 name=>"Silly Musician",
2342 When subclassing ResultSet never attempt to override this method. Since
2343 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2344 lot of the internals simply never call it, so your override will be
2345 bypassed more often than not. Override either L<new|DBIx::Class::Row/new>
2346 or L<insert|DBIx::Class::Row/insert> depending on how early in the
2347 L</create> process you need to intervene.
2354 my ($self, $attrs) = @_;
2355 $self->throw_exception( "create needs a hashref" )
2356 unless ref $attrs eq 'HASH';
2357 return $self->new_result($attrs)->insert;
2360 =head2 find_or_create
2364 =item Arguments: \%vals, \%attrs?
2366 =item Return Value: $rowobject
2370 $cd->cd_to_producer->find_or_create({ producer => $producer },
2371 { key => 'primary' });
2373 Tries to find a record based on its primary key or unique constraints; if none
2374 is found, creates one and returns that instead.
2376 my $cd = $schema->resultset('CD')->find_or_create({
2378 artist => 'Massive Attack',
2379 title => 'Mezzanine',
2383 Also takes an optional C<key> attribute, to search by a specific key or unique
2384 constraint. For example:
2386 my $cd = $schema->resultset('CD')->find_or_create(
2388 artist => 'Massive Attack',
2389 title => 'Mezzanine',
2391 { key => 'cd_artist_title' }
2394 B<Note>: Because find_or_create() reads from the database and then
2395 possibly inserts based on the result, this method is subject to a race
2396 condition. Another process could create a record in the table after
2397 the find has completed and before the create has started. To avoid
2398 this problem, use find_or_create() inside a transaction.
2400 B<Note>: Take care when using C<find_or_create> with a table having
2401 columns with default values that you intend to be automatically
2402 supplied by the database (e.g. an auto_increment primary key column).
2403 In normal usage, the value of such columns should NOT be included at
2404 all in the call to C<find_or_create>, even when set to C<undef>.
2406 See also L</find> and L</update_or_create>. For information on how to declare
2407 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2411 sub find_or_create {
2413 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2414 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2415 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2418 return $self->create($hash);
2421 =head2 update_or_create
2425 =item Arguments: \%col_values, { key => $unique_constraint }?
2427 =item Return Value: $rowobject
2431 $resultset->update_or_create({ col => $val, ... });
2433 First, searches for an existing row matching one of the unique constraints
2434 (including the primary key) on the source of this resultset. If a row is
2435 found, updates it with the other given column values. Otherwise, creates a new
2438 Takes an optional C<key> attribute to search on a specific unique constraint.
2441 # In your application
2442 my $cd = $schema->resultset('CD')->update_or_create(
2444 artist => 'Massive Attack',
2445 title => 'Mezzanine',
2448 { key => 'cd_artist_title' }
2451 $cd->cd_to_producer->update_or_create({
2452 producer => $producer,
2459 If no C<key> is specified, it searches on all unique constraints defined on the
2460 source, including the primary key.
2462 If the C<key> is specified as C<primary>, it searches only on the primary key.
2464 See also L</find> and L</find_or_create>. For information on how to declare
2465 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2467 B<Note>: Take care when using C<update_or_create> with a table having
2468 columns with default values that you intend to be automatically
2469 supplied by the database (e.g. an auto_increment primary key column).
2470 In normal usage, the value of such columns should NOT be included at
2471 all in the call to C<update_or_create>, even when set to C<undef>.
2475 sub update_or_create {
2477 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2478 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2480 my $row = $self->find($cond, $attrs);
2482 $row->update($cond);
2486 return $self->create($cond);
2489 =head2 update_or_new
2493 =item Arguments: \%col_values, { key => $unique_constraint }?
2495 =item Return Value: $rowobject
2499 $resultset->update_or_new({ col => $val, ... });
2501 First, searches for an existing row matching one of the unique constraints
2502 (including the primary key) on the source of this resultset. If a row is
2503 found, updates it with the other given column values. Otherwise, instantiate
2504 a new result object and return it. The object will not be saved into your storage
2505 until you call L<DBIx::Class::Row/insert> on it.
2507 Takes an optional C<key> attribute to search on a specific unique constraint.
2510 # In your application
2511 my $cd = $schema->resultset('CD')->update_or_new(
2513 artist => 'Massive Attack',
2514 title => 'Mezzanine',
2517 { key => 'cd_artist_title' }
2520 if ($cd->in_storage) {
2521 # the cd was updated
2524 # the cd is not yet in the database, let's insert it
2528 B<Note>: Take care when using C<update_or_new> with a table having
2529 columns with default values that you intend to be automatically
2530 supplied by the database (e.g. an auto_increment primary key column).
2531 In normal usage, the value of such columns should NOT be included at
2532 all in the call to C<update_or_new>, even when set to C<undef>.
2534 See also L</find>, L</find_or_create> and L</find_or_new>.
2540 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2541 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2543 my $row = $self->find( $cond, $attrs );
2544 if ( defined $row ) {
2545 $row->update($cond);
2549 return $self->new_result($cond);
2556 =item Arguments: none
2558 =item Return Value: \@cache_objects | undef
2562 Gets the contents of the cache for the resultset, if the cache is set.
2564 The cache is populated either by using the L</prefetch> attribute to
2565 L</search> or by calling L</set_cache>.
2577 =item Arguments: \@cache_objects
2579 =item Return Value: \@cache_objects
2583 Sets the contents of the cache for the resultset. Expects an arrayref
2584 of objects of the same class as those produced by the resultset. Note that
2585 if the cache is set the resultset will return the cached objects rather
2586 than re-querying the database even if the cache attr is not set.
2588 The contents of the cache can also be populated by using the
2589 L</prefetch> attribute to L</search>.
2594 my ( $self, $data ) = @_;
2595 $self->throw_exception("set_cache requires an arrayref")
2596 if defined($data) && (ref $data ne 'ARRAY');
2597 $self->{all_cache} = $data;
2604 =item Arguments: none
2606 =item Return Value: undef
2610 Clears the cache for the resultset.
2615 shift->set_cache(undef);
2622 =item Arguments: none
2624 =item Return Value: true, if the resultset has been paginated
2632 return !!$self->{attrs}{page};
2639 =item Arguments: none
2641 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2649 return scalar $self->result_source->storage->_extract_order_columns($self->{attrs}{order_by});
2652 =head2 related_resultset
2656 =item Arguments: $relationship_name
2658 =item Return Value: $resultset
2662 Returns a related resultset for the supplied relationship name.
2664 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2668 sub related_resultset {
2669 my ($self, $rel) = @_;
2671 $self->{related_resultsets} ||= {};
2672 return $self->{related_resultsets}{$rel} ||= do {
2673 my $rsrc = $self->result_source;
2674 my $rel_info = $rsrc->relationship_info($rel);
2676 $self->throw_exception(
2677 "search_related: result source '" . $rsrc->source_name .
2678 "' has no such relationship $rel")
2681 my $attrs = $self->_chain_relationship($rel);
2683 my $join_count = $attrs->{seen_join}{$rel};
2685 my $alias = $self->result_source->storage
2686 ->relname_to_table_alias($rel, $join_count);
2688 # since this is search_related, and we already slid the select window inwards
2689 # (the select/as attrs were deleted in the beginning), we need to flip all
2690 # left joins to inner, so we get the expected results
2691 # read the comment on top of the actual function to see what this does
2692 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
2695 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2696 delete @{$attrs}{qw(result_class alias)};
2700 if (my $cache = $self->get_cache) {
2701 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2702 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
2707 my $rel_source = $rsrc->related_source($rel);
2711 # The reason we do this now instead of passing the alias to the
2712 # search_rs below is that if you wrap/overload resultset on the
2713 # source you need to know what alias it's -going- to have for things
2714 # to work sanely (e.g. RestrictWithObject wants to be able to add
2715 # extra query restrictions, and these may need to be $alias.)
2717 my $rel_attrs = $rel_source->resultset_attributes;
2718 local $rel_attrs->{alias} = $alias;
2720 $rel_source->resultset
2724 where => $attrs->{where},
2727 $new->set_cache($new_cache) if $new_cache;
2732 =head2 current_source_alias
2736 =item Arguments: none
2738 =item Return Value: $source_alias
2742 Returns the current table alias for the result source this resultset is built
2743 on, that will be used in the SQL query. Usually it is C<me>.
2745 Currently the source alias that refers to the result set returned by a
2746 L</search>/L</find> family method depends on how you got to the resultset: it's
2747 C<me> by default, but eg. L</search_related> aliases it to the related result
2748 source name (and keeps C<me> referring to the original result set). The long
2749 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
2750 (and make this method unnecessary).
2752 Thus it's currently necessary to use this method in predefined queries (see
2753 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
2754 source alias of the current result set:
2756 # in a result set class
2758 my ($self, $user) = @_;
2760 my $me = $self->current_source_alias;
2762 return $self->search(
2763 "$me.modified" => $user->id,
2769 sub current_source_alias {
2772 return ($self->{attrs} || {})->{alias} || 'me';
2775 =head2 as_subselect_rs
2779 =item Arguments: none
2781 =item Return Value: $resultset
2785 Act as a barrier to SQL symbols. The resultset provided will be made into a
2786 "virtual view" by including it as a subquery within the from clause. From this
2787 point on, any joined tables are inaccessible to ->search on the resultset (as if
2788 it were simply where-filtered without joins). For example:
2790 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
2792 # 'x' now pollutes the query namespace
2794 # So the following works as expected
2795 my $ok_rs = $rs->search({'x.other' => 1});
2797 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
2798 # def) we look for one row with contradictory terms and join in another table
2799 # (aliased 'x_2') which we never use
2800 my $broken_rs = $rs->search({'x.name' => 'def'});
2802 my $rs2 = $rs->as_subselect_rs;
2804 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
2805 my $not_joined_rs = $rs2->search({'x.other' => 1});
2807 # works as expected: finds a 'table' row related to two x rows (abc and def)
2808 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
2810 Another example of when one might use this would be to select a subset of
2811 columns in a group by clause:
2813 my $rs = $schema->resultset('Bar')->search(undef, {
2814 group_by => [qw{ id foo_id baz_id }],
2815 })->as_subselect_rs->search(undef, {
2816 columns => [qw{ id foo_id }]
2819 In the above example normally columns would have to be equal to the group by,
2820 but because we isolated the group by into a subselect the above works.
2824 sub as_subselect_rs {
2827 my $attrs = $self->_resolved_attrs;
2829 my $fresh_rs = (ref $self)->new (
2830 $self->result_source
2833 # these pieces will be locked in the subquery
2834 delete $fresh_rs->{cond};
2835 delete @{$fresh_rs->{attrs}}{qw/where bind/};
2837 return $fresh_rs->search( {}, {
2839 $attrs->{alias} => $self->as_query,
2840 -alias => $attrs->{alias},
2841 -source_handle => $self->result_source->handle,
2843 alias => $attrs->{alias},
2847 # This code is called by search_related, and makes sure there
2848 # is clear separation between the joins before, during, and
2849 # after the relationship. This information is needed later
2850 # in order to properly resolve prefetch aliases (any alias
2851 # with a relation_chain_depth less than the depth of the
2852 # current prefetch is not considered)
2854 # The increments happen twice per join. An even number means a
2855 # relationship specified via a search_related, whereas an odd
2856 # number indicates a join/prefetch added via attributes
2858 # Also this code will wrap the current resultset (the one we
2859 # chain to) in a subselect IFF it contains limiting attributes
2860 sub _chain_relationship {
2861 my ($self, $rel) = @_;
2862 my $source = $self->result_source;
2863 my $attrs = { %{$self->{attrs}||{}} };
2865 # we need to take the prefetch the attrs into account before we
2866 # ->_resolve_join as otherwise they get lost - captainL
2867 my $join = $self->_merge_attr( $attrs->{join}, $attrs->{prefetch} );
2869 delete @{$attrs}{qw/join prefetch collapse group_by distinct select as columns +select +as +columns/};
2871 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
2874 my @force_subq_attrs = qw/offset rows group_by having/;
2877 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
2879 $self->_has_resolved_attr (@force_subq_attrs)
2881 # Nuke the prefetch (if any) before the new $rs attrs
2882 # are resolved (prefetch is useless - we are wrapping
2883 # a subquery anyway).
2884 my $rs_copy = $self->search;
2885 $rs_copy->{attrs}{join} = $self->_merge_attr (
2886 $rs_copy->{attrs}{join},
2887 delete $rs_copy->{attrs}{prefetch},
2891 -source_handle => $source->handle,
2892 -alias => $attrs->{alias},
2893 $attrs->{alias} => $rs_copy->as_query,
2895 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
2896 $seen->{-relation_chain_depth} = 0;
2898 elsif ($attrs->{from}) { #shallow copy suffices
2899 $from = [ @{$attrs->{from}} ];
2903 -source_handle => $source->handle,
2904 -alias => $attrs->{alias},
2905 $attrs->{alias} => $source->from,
2909 my $jpath = ($seen->{-relation_chain_depth})
2910 ? $from->[-1][0]{-join_path}
2913 my @requested_joins = $source->_resolve_join(
2920 push @$from, @requested_joins;
2922 $seen->{-relation_chain_depth}++;
2924 # if $self already had a join/prefetch specified on it, the requested
2925 # $rel might very well be already included. What we do in this case
2926 # is effectively a no-op (except that we bump up the chain_depth on
2927 # the join in question so we could tell it *is* the search_related)
2930 # we consider the last one thus reverse
2931 for my $j (reverse @requested_joins) {
2932 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
2933 if ($rel eq $last_j) {
2934 $j->[0]{-relation_chain_depth}++;
2940 unless ($already_joined) {
2941 push @$from, $source->_resolve_join(
2949 $seen->{-relation_chain_depth}++;
2951 return {%$attrs, from => $from, seen_join => $seen};
2954 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
2955 sub _resolved_attrs_copy {
2957 return { %{$self->_resolved_attrs (@_)} };
2960 sub _resolved_attrs {
2962 return $self->{_attrs} if $self->{_attrs};
2964 my $attrs = { %{ $self->{attrs} || {} } };
2965 my $source = $self->result_source;
2966 my $alias = $attrs->{alias};
2968 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
2971 # build columns (as long as select isn't set) into a set of as/select hashes
2972 unless ( $attrs->{select} ) {
2975 if ( ref $attrs->{columns} eq 'ARRAY' ) {
2976 @cols = @{ delete $attrs->{columns}}
2977 } elsif ( defined $attrs->{columns} ) {
2978 @cols = delete $attrs->{columns}
2980 @cols = $source->columns
2984 if ( ref $_ eq 'HASH' ) {
2987 my $key = /^\Q${alias}.\E(.+)$/
2993 push @colbits, { $key => $value };
2998 # add the additional columns on
2999 foreach (qw{include_columns +columns}) {
3000 if ( $attrs->{$_} ) {
3001 my @list = ( ref($attrs->{$_}) eq 'ARRAY' )
3002 ? @{ delete $attrs->{$_} }
3003 : delete $attrs->{$_};
3005 if ( ref($_) eq 'HASH' ) {
3008 my $key = ( split /\./, $_ )[-1];
3009 my $value = ( /\./ ? $_ : "$alias.$_" );
3010 push @colbits, { $key => $value };
3016 # start with initial select items
3017 if ( $attrs->{select} ) {
3019 ( ref $attrs->{select} eq 'ARRAY' )
3020 ? [ @{ $attrs->{select} } ]
3021 : [ $attrs->{select} ];
3023 if ( $attrs->{as} ) {
3026 ref $attrs->{as} eq 'ARRAY'
3027 ? [ @{ $attrs->{as} } ]
3031 $attrs->{as} = [ map {
3032 m/^\Q${alias}.\E(.+)$/
3035 } @{ $attrs->{select} }
3041 # otherwise we intialise select & as to empty
3042 $attrs->{select} = [];
3046 # now add colbits to select/as
3047 push @{ $attrs->{select} }, map values %{$_}, @colbits;
3048 push @{ $attrs->{as} }, map keys %{$_}, @colbits;
3050 if ( my $adds = delete $attrs->{'+select'} ) {
3051 $adds = [$adds] unless ref $adds eq 'ARRAY';
3052 push @{ $attrs->{select} },
3053 map { /\./ || ref $_ ? $_ : "$alias.$_" } @$adds;
3055 if ( my $adds = delete $attrs->{'+as'} ) {
3056 $adds = [$adds] unless ref $adds eq 'ARRAY';
3057 push @{ $attrs->{as} }, @$adds;
3060 $attrs->{from} ||= [{
3061 -source_handle => $source->handle,
3062 -alias => $self->{attrs}{alias},
3063 $self->{attrs}{alias} => $source->from,
3066 if ( $attrs->{join} || $attrs->{prefetch} ) {
3068 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3069 if ref $attrs->{from} ne 'ARRAY';
3071 my $join = delete $attrs->{join} || {};
3073 if ( defined $attrs->{prefetch} ) {
3074 $join = $self->_merge_attr( $join, $attrs->{prefetch} );
3077 $attrs->{from} = # have to copy here to avoid corrupting the original
3079 @{ $attrs->{from} },
3080 $source->_resolve_join(
3083 { %{ $attrs->{seen_join} || {} } },
3084 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3085 ? $attrs->{from}[-1][0]{-join_path}
3092 if ( defined $attrs->{order_by} ) {
3093 $attrs->{order_by} = (
3094 ref( $attrs->{order_by} ) eq 'ARRAY'
3095 ? [ @{ $attrs->{order_by} } ]
3096 : [ $attrs->{order_by} || () ]
3100 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3101 $attrs->{group_by} = [ $attrs->{group_by} ];
3104 # generate the distinct induced group_by early, as prefetch will be carried via a
3105 # subquery (since a group_by is present)
3106 if (delete $attrs->{distinct}) {
3107 if ($attrs->{group_by}) {
3108 carp ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3111 my $storage = $self->result_source->schema->storage;
3112 my $rs_column_list = $storage->_resolve_column_info ($attrs->{from});
3114 my $group_spec = $attrs->{group_by} = [];
3117 for (@{$attrs->{select}}) {
3118 if (! ref($_) or ref ($_) ne 'HASH' ) {
3119 push @$group_spec, $_;
3121 if ($rs_column_list->{$_} and $_ !~ /\./ ) {
3122 # add a fully qualified version as well
3123 $group_index{"$rs_column_list->{$_}{-source_alias}.$_"}++;
3127 # add any order_by parts that are not already present in the group_by
3128 # we need to be careful not to add any named functions/aggregates
3129 # i.e. select => [ ... { count => 'foo', -as 'foocount' } ... ]
3130 for my $chunk ($storage->_extract_order_columns($attrs->{order_by})) {
3132 # only consider real columns (for functions the user got to do an explicit group_by)
3133 my $colinfo = $rs_column_list->{$chunk}
3136 $chunk = "$colinfo->{-source_alias}.$chunk" if $chunk !~ /\./;
3137 push @$group_spec, $chunk unless $group_index{$chunk}++;
3142 $attrs->{collapse} ||= {};
3143 if ( my $prefetch = delete $attrs->{prefetch} ) {
3144 $prefetch = $self->_merge_attr( {}, $prefetch );
3146 my $prefetch_ordering = [];
3148 # this is a separate structure (we don't look in {from} directly)
3149 # as the resolver needs to shift things off the lists to work
3150 # properly (identical-prefetches on different branches)
3152 if (ref $attrs->{from} eq 'ARRAY') {
3154 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3156 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3157 next unless $j->[0]{-alias};
3158 next unless $j->[0]{-join_path};
3159 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3161 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3164 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3165 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3170 $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
3172 # we need to somehow mark which columns came from prefetch
3173 $attrs->{_prefetch_select} = [ map { $_->[0] } @prefetch ];
3175 push @{ $attrs->{select} }, @{$attrs->{_prefetch_select}};
3176 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
3178 push( @{$attrs->{order_by}}, @$prefetch_ordering );
3179 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
3182 # if both page and offset are specified, produce a combined offset
3183 # even though it doesn't make much sense, this is what pre 081xx has
3185 if (my $page = delete $attrs->{page}) {
3187 ($attrs->{rows} * ($page - 1))
3189 ($attrs->{offset} || 0)
3193 return $self->{_attrs} = $attrs;
3197 my ($self, $attr) = @_;
3199 if (ref $attr eq 'HASH') {
3200 return $self->_rollout_hash($attr);
3201 } elsif (ref $attr eq 'ARRAY') {
3202 return $self->_rollout_array($attr);
3208 sub _rollout_array {
3209 my ($self, $attr) = @_;
3212 foreach my $element (@{$attr}) {
3213 if (ref $element eq 'HASH') {
3214 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3215 } elsif (ref $element eq 'ARRAY') {
3216 # XXX - should probably recurse here
3217 push( @rolled_array, @{$self->_rollout_array($element)} );
3219 push( @rolled_array, $element );
3222 return \@rolled_array;
3226 my ($self, $attr) = @_;
3229 foreach my $key (keys %{$attr}) {
3230 push( @rolled_array, { $key => $attr->{$key} } );
3232 return \@rolled_array;
3235 sub _calculate_score {
3236 my ($self, $a, $b) = @_;
3238 if (defined $a xor defined $b) {
3241 elsif (not defined $a) {
3245 if (ref $b eq 'HASH') {
3246 my ($b_key) = keys %{$b};
3247 if (ref $a eq 'HASH') {
3248 my ($a_key) = keys %{$a};
3249 if ($a_key eq $b_key) {
3250 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3255 return ($a eq $b_key) ? 1 : 0;
3258 if (ref $a eq 'HASH') {
3259 my ($a_key) = keys %{$a};
3260 return ($b eq $a_key) ? 1 : 0;
3262 return ($b eq $a) ? 1 : 0;
3268 my ($self, $orig, $import) = @_;
3270 return $import unless defined($orig);
3271 return $orig unless defined($import);
3273 $orig = $self->_rollout_attr($orig);
3274 $import = $self->_rollout_attr($import);
3277 foreach my $import_element ( @{$import} ) {
3278 # find best candidate from $orig to merge $b_element into
3279 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3280 foreach my $orig_element ( @{$orig} ) {
3281 my $score = $self->_calculate_score( $orig_element, $import_element );
3282 if ($score > $best_candidate->{score}) {
3283 $best_candidate->{position} = $position;
3284 $best_candidate->{score} = $score;
3288 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3290 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3291 push( @{$orig}, $import_element );
3293 my $orig_best = $orig->[$best_candidate->{position}];
3294 # merge orig_best and b_element together and replace original with merged
3295 if (ref $orig_best ne 'HASH') {
3296 $orig->[$best_candidate->{position}] = $import_element;
3297 } elsif (ref $import_element eq 'HASH') {
3298 my ($key) = keys %{$orig_best};
3299 $orig->[$best_candidate->{position}] = { $key => $self->_merge_attr($orig_best->{$key}, $import_element->{$key}) };
3302 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3312 $self->_source_handle($_[0]->handle);
3314 $self->_source_handle->resolve;
3318 =head2 throw_exception
3320 See L<DBIx::Class::Schema/throw_exception> for details.
3324 sub throw_exception {
3327 if (ref $self && $self->_source_handle->schema) {
3328 $self->_source_handle->schema->throw_exception(@_)
3331 DBIx::Class::Exception->throw(@_);
3335 # XXX: FIXME: Attributes docs need clearing up
3339 Attributes are used to refine a ResultSet in various ways when
3340 searching for data. They can be passed to any method which takes an
3341 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3344 These are in no particular order:
3350 =item Value: ( $order_by | \@order_by | \%order_by )
3354 Which column(s) to order the results by.
3356 [The full list of suitable values is documented in
3357 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3360 If a single column name, or an arrayref of names is supplied, the
3361 argument is passed through directly to SQL. The hashref syntax allows
3362 for connection-agnostic specification of ordering direction:
3364 For descending order:
3366 order_by => { -desc => [qw/col1 col2 col3/] }
3368 For explicit ascending order:
3370 order_by => { -asc => 'col' }
3372 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3373 supported, although you are strongly encouraged to use the hashref
3374 syntax as outlined above.
3380 =item Value: \@columns
3384 Shortcut to request a particular set of columns to be retrieved. Each
3385 column spec may be a string (a table column name), or a hash (in which
3386 case the key is the C<as> value, and the value is used as the C<select>
3387 expression). Adds C<me.> onto the start of any column without a C<.> in
3388 it and sets C<select> from that, then auto-populates C<as> from
3389 C<select> as normal. (You may also use the C<cols> attribute, as in
3390 earlier versions of DBIC.)
3392 Essentially C<columns> does the same as L</select> and L</as>.
3394 columns => [ 'foo', { bar => 'baz' } ]
3398 select => [qw/foo baz/],
3405 =item Value: \@columns
3409 Indicates additional columns to be selected from storage. Works the same
3410 as L</columns> but adds columns to the selection. (You may also use the
3411 C<include_columns> attribute, as in earlier versions of DBIC). For
3414 $schema->resultset('CD')->search(undef, {
3415 '+columns' => ['artist.name'],
3419 would return all CDs and include a 'name' column to the information
3420 passed to object inflation. Note that the 'artist' is the name of the
3421 column (or relationship) accessor, and 'name' is the name of the column
3422 accessor in the related table.
3424 =head2 include_columns
3428 =item Value: \@columns
3432 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3438 =item Value: \@select_columns
3442 Indicates which columns should be selected from the storage. You can use
3443 column names, or in the case of RDBMS back ends, function or stored procedure
3446 $rs = $schema->resultset('Employee')->search(undef, {
3449 { count => 'employeeid' },
3450 { max => { length => 'name' }, -as => 'longest_name' }
3455 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
3457 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
3458 use L</select>, to instruct DBIx::Class how to store the result of the column.
3459 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
3460 identifier aliasing. You can however alias a function, so you can use it in
3461 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
3462 attribute> supplied as shown in the example above.
3468 Indicates additional columns to be selected from storage. Works the same as
3469 L</select> but adds columns to the default selection, instead of specifying
3478 Indicates additional column names for those added via L</+select>. See L</as>.
3486 =item Value: \@inflation_names
3490 Indicates column names for object inflation. That is L</as> indicates the
3491 slot name in which the column value will be stored within the
3492 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
3493 identifier by the C<get_column> method (or via the object accessor B<if one
3494 with the same name already exists>) as shown below. The L</as> attribute has
3495 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
3497 $rs = $schema->resultset('Employee')->search(undef, {
3500 { count => 'employeeid' },
3501 { max => { length => 'name' }, -as => 'longest_name' }
3510 If the object against which the search is performed already has an accessor
3511 matching a column name specified in C<as>, the value can be retrieved using
3512 the accessor as normal:
3514 my $name = $employee->name();
3516 If on the other hand an accessor does not exist in the object, you need to
3517 use C<get_column> instead:
3519 my $employee_count = $employee->get_column('employee_count');
3521 You can create your own accessors if required - see
3522 L<DBIx::Class::Manual::Cookbook> for details.
3528 =item Value: ($rel_name | \@rel_names | \%rel_names)
3532 Contains a list of relationships that should be joined for this query. For
3535 # Get CDs by Nine Inch Nails
3536 my $rs = $schema->resultset('CD')->search(
3537 { 'artist.name' => 'Nine Inch Nails' },
3538 { join => 'artist' }
3541 Can also contain a hash reference to refer to the other relation's relations.
3544 package MyApp::Schema::Track;
3545 use base qw/DBIx::Class/;
3546 __PACKAGE__->table('track');
3547 __PACKAGE__->add_columns(qw/trackid cd position title/);
3548 __PACKAGE__->set_primary_key('trackid');
3549 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3552 # In your application
3553 my $rs = $schema->resultset('Artist')->search(
3554 { 'track.title' => 'Teardrop' },
3556 join => { cd => 'track' },
3557 order_by => 'artist.name',
3561 You need to use the relationship (not the table) name in conditions,
3562 because they are aliased as such. The current table is aliased as "me", so
3563 you need to use me.column_name in order to avoid ambiguity. For example:
3565 # Get CDs from 1984 with a 'Foo' track
3566 my $rs = $schema->resultset('CD')->search(
3569 'tracks.name' => 'Foo'
3571 { join => 'tracks' }
3574 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3575 similarly for a third time). For e.g.
3577 my $rs = $schema->resultset('Artist')->search({
3578 'cds.title' => 'Down to Earth',
3579 'cds_2.title' => 'Popular',
3581 join => [ qw/cds cds/ ],
3584 will return a set of all artists that have both a cd with title 'Down
3585 to Earth' and a cd with title 'Popular'.
3587 If you want to fetch related objects from other tables as well, see C<prefetch>
3590 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3596 =item Value: ($rel_name | \@rel_names | \%rel_names)
3600 Contains one or more relationships that should be fetched along with
3601 the main query (when they are accessed afterwards the data will
3602 already be available, without extra queries to the database). This is
3603 useful for when you know you will need the related objects, because it
3604 saves at least one query:
3606 my $rs = $schema->resultset('Tag')->search(
3615 The initial search results in SQL like the following:
3617 SELECT tag.*, cd.*, artist.* FROM tag
3618 JOIN cd ON tag.cd = cd.cdid
3619 JOIN artist ON cd.artist = artist.artistid
3621 L<DBIx::Class> has no need to go back to the database when we access the
3622 C<cd> or C<artist> relationships, which saves us two SQL statements in this
3625 Simple prefetches will be joined automatically, so there is no need
3626 for a C<join> attribute in the above search.
3628 C<prefetch> can be used with the following relationship types: C<belongs_to>,
3629 C<has_one> (or if you're using C<add_relationship>, any relationship declared
3630 with an accessor type of 'single' or 'filter'). A more complex example that
3631 prefetches an artists cds, the tracks on those cds, and the tags associated
3632 with that artist is given below (assuming many-to-many from artists to tags):
3634 my $rs = $schema->resultset('Artist')->search(
3638 { cds => 'tracks' },
3639 { artist_tags => 'tags' }
3645 B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
3646 attributes will be ignored.
3648 B<CAVEATs>: Prefetch does a lot of deep magic. As such, it may not behave
3649 exactly as you might expect.
3655 Prefetch uses the L</cache> to populate the prefetched relationships. This
3656 may or may not be what you want.
3660 If you specify a condition on a prefetched relationship, ONLY those
3661 rows that match the prefetched condition will be fetched into that relationship.
3662 This means that adding prefetch to a search() B<may alter> what is returned by
3663 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
3665 my $artist_rs = $schema->resultset('Artist')->search({
3671 my $count = $artist_rs->first->cds->count;
3673 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
3675 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
3677 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
3679 that cmp_ok() may or may not pass depending on the datasets involved. This
3680 behavior may or may not survive the 0.09 transition.
3692 Makes the resultset paged and specifies the page to retrieve. Effectively
3693 identical to creating a non-pages resultset and then calling ->page($page)
3696 If L<rows> attribute is not specified it defaults to 10 rows per page.
3698 When you have a paged resultset, L</count> will only return the number
3699 of rows in the page. To get the total, use the L</pager> and call
3700 C<total_entries> on it.
3710 Specifies the maximum number of rows for direct retrieval or the number of
3711 rows per page if the page attribute or method is used.
3717 =item Value: $offset
3721 Specifies the (zero-based) row number for the first row to be returned, or the
3722 of the first row of the first page if paging is used.
3728 =item Value: \@columns
3732 A arrayref of columns to group by. Can include columns of joined tables.
3734 group_by => [qw/ column1 column2 ... /]
3740 =item Value: $condition
3744 HAVING is a select statement attribute that is applied between GROUP BY and
3745 ORDER BY. It is applied to the after the grouping calculations have been
3748 having => { 'count(employee)' => { '>=', 100 } }
3754 =item Value: (0 | 1)
3758 Set to 1 to group by all columns. If the resultset already has a group_by
3759 attribute, this setting is ignored and an appropriate warning is issued.
3765 Adds to the WHERE clause.
3767 # only return rows WHERE deleted IS NULL for all searches
3768 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
3770 Can be overridden by passing C<< { where => undef } >> as an attribute
3777 Set to 1 to cache search results. This prevents extra SQL queries if you
3778 revisit rows in your ResultSet:
3780 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
3782 while( my $artist = $resultset->next ) {
3786 $rs->first; # without cache, this would issue a query
3788 By default, searches are not cached.
3790 For more examples of using these attributes, see
3791 L<DBIx::Class::Manual::Cookbook>.
3797 =item Value: ( 'update' | 'shared' )
3801 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT