1 package DBIx::Class::ResultSet;
9 use Carp::Clan qw/^DBIx::Class/;
10 use DBIx::Class::Exception;
13 use DBIx::Class::ResultSetColumn;
14 use DBIx::Class::ResultSourceHandle;
17 use base qw/DBIx::Class/;
19 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class _source_handle/);
23 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
27 my $users_rs = $schema->resultset('User');
28 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
29 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
33 A ResultSet is an object which stores a set of conditions representing
34 a query. It is the backbone of DBIx::Class (i.e. the really
35 important/useful bit).
37 No SQL is executed on the database when a ResultSet is created, it
38 just stores all the conditions needed to create the query.
40 A basic ResultSet representing the data of an entire table is returned
41 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
42 L<Source|DBIx::Class::Manual::Glossary/Source> name.
44 my $users_rs = $schema->resultset('User');
46 A new ResultSet is returned from calling L</search> on an existing
47 ResultSet. The new one will contain all the conditions of the
48 original, plus any new conditions added in the C<search> call.
50 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
51 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
54 The query that the ResultSet represents is B<only> executed against
55 the database when these methods are called:
56 L</find> L</next> L</all> L</first> L</single> L</count>
60 =head2 Chaining resultsets
62 Let's say you've got a query that needs to be run to return some data
63 to the user. But, you have an authorization system in place that
64 prevents certain users from seeing certain information. So, you want
65 to construct the basic query in one method, but add constraints to it in
70 my $request = $self->get_request; # Get a request object somehow.
71 my $schema = $self->get_schema; # Get the DBIC schema object somehow.
73 my $cd_rs = $schema->resultset('CD')->search({
74 title => $request->param('title'),
75 year => $request->param('year'),
78 $self->apply_security_policy( $cd_rs );
83 sub apply_security_policy {
92 =head3 Resolving conditions and attributes
94 When a resultset is chained from another resultset, conditions and
95 attributes with the same keys need resolving.
97 L</join>, L</prefetch>, L</+select>, L</+as> attributes are merged
98 into the existing ones from the original resultset.
100 The L</where>, L</having> attribute, and any search conditions are
101 merged with an SQL C<AND> to the existing condition from the original
104 All other attributes are overridden by any new ones supplied in the
107 =head2 Multiple queries
109 Since a resultset just defines a query, you can do all sorts of
110 things with it with the same object.
112 # Don't hit the DB yet.
113 my $cd_rs = $schema->resultset('CD')->search({
114 title => 'something',
118 # Each of these hits the DB individually.
119 my $count = $cd_rs->count;
120 my $most_recent = $cd_rs->get_column('date_released')->max();
121 my @records = $cd_rs->all;
123 And it's not just limited to SELECT statements.
129 $cd_rs->create({ artist => 'Fred' });
131 Which is the same as:
133 $schema->resultset('CD')->create({
134 title => 'something',
139 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
143 If a resultset is used in a numeric context it returns the L</count>.
144 However, if it is used in a boolean context it is always true. So if
145 you want to check if a resultset has any results use C<if $rs != 0>.
146 C<if $rs> will always be true.
154 =item Arguments: $source, \%$attrs
156 =item Return Value: $rs
160 The resultset constructor. Takes a source object (usually a
161 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
162 L</ATTRIBUTES> below). Does not perform any queries -- these are
163 executed as needed by the other methods.
165 Generally you won't need to construct a resultset manually. You'll
166 automatically get one from e.g. a L</search> called in scalar context:
168 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
170 IMPORTANT: If called on an object, proxies to new_result instead so
172 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
174 will return a CD object, not a ResultSet.
180 return $class->new_result(@_) if ref $class;
182 my ($source, $attrs) = @_;
183 $source = $source->handle
184 unless $source->isa('DBIx::Class::ResultSourceHandle');
185 $attrs = { %{$attrs||{}} };
187 if ($attrs->{page}) {
188 $attrs->{rows} ||= 10;
191 $attrs->{alias} ||= 'me';
193 # Creation of {} and bless separated to mitigate RH perl bug
194 # see https://bugzilla.redhat.com/show_bug.cgi?id=196836
196 _source_handle => $source,
197 cond => $attrs->{where},
206 $attrs->{result_class} || $source->resolve->result_class
216 =item Arguments: $cond, \%attrs?
218 =item Return Value: $resultset (scalar context), @row_objs (list context)
222 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
223 my $new_rs = $cd_rs->search({ year => 2005 });
225 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
226 # year = 2005 OR year = 2004
228 If you need to pass in additional attributes but no additional condition,
229 call it as C<search(undef, \%attrs)>.
231 # "SELECT name, artistid FROM $artist_table"
232 my @all_artists = $schema->resultset('Artist')->search(undef, {
233 columns => [qw/name artistid/],
236 For a list of attributes that can be passed to C<search>, see
237 L</ATTRIBUTES>. For more examples of using this function, see
238 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
239 documentation for the first argument, see L<SQL::Abstract>.
241 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
247 my $rs = $self->search_rs( @_ );
248 return (wantarray ? $rs->all : $rs);
255 =item Arguments: $cond, \%attrs?
257 =item Return Value: $resultset
261 This method does the same exact thing as search() except it will
262 always return a resultset, even in list context.
269 # Special-case handling for (undef, undef).
270 if ( @_ == 2 && !defined $_[1] && !defined $_[0] ) {
275 $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
276 my $our_attrs = { %{$self->{attrs}} };
277 my $having = delete $our_attrs->{having};
278 my $where = delete $our_attrs->{where};
282 my %safe = (alias => 1, cache => 1);
285 (@_ && defined($_[0])) # @_ == () or (undef)
287 (keys %$attrs # empty attrs or only 'safe' attrs
288 && List::Util::first { !$safe{$_} } keys %$attrs)
290 # no search, effectively just a clone
291 $rows = $self->get_cache;
294 # reset the selector list
295 if (List::Util::first { exists $attrs->{$_} } qw{columns select as}) {
296 delete @{$our_attrs}{qw{select as columns +select +as +columns include_columns}};
299 my $new_attrs = { %{$our_attrs}, %{$attrs} };
301 # merge new attrs into inherited
302 foreach my $key (qw/join prefetch +select +as +columns include_columns bind/) {
303 next unless exists $attrs->{$key};
304 $new_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key});
309 (@_ == 1 || ref $_[0] eq "HASH")
311 (ref $_[0] eq 'HASH')
313 (keys %{ $_[0] } > 0)
321 ? $self->throw_exception("Odd number of arguments to search")
328 if (defined $where) {
329 $new_attrs->{where} = (
330 defined $new_attrs->{where}
333 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
334 } $where, $new_attrs->{where}
341 $new_attrs->{where} = (
342 defined $new_attrs->{where}
345 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
346 } $cond, $new_attrs->{where}
352 if (defined $having) {
353 $new_attrs->{having} = (
354 defined $new_attrs->{having}
357 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
358 } $having, $new_attrs->{having}
364 my $rs = (ref $self)->new($self->result_source, $new_attrs);
366 $rs->set_cache($rows) if ($rows);
371 =head2 search_literal
375 =item Arguments: $sql_fragment, @bind_values
377 =item Return Value: $resultset (scalar context), @row_objs (list context)
381 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
382 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
384 Pass a literal chunk of SQL to be added to the conditional part of the
387 CAVEAT: C<search_literal> is provided for Class::DBI compatibility and should
388 only be used in that context. C<search_literal> is a convenience method.
389 It is equivalent to calling $schema->search(\[]), but if you want to ensure
390 columns are bound correctly, use C<search>.
392 Example of how to use C<search> instead of C<search_literal>
394 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
395 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
398 See L<DBIx::Class::Manual::Cookbook/Searching> and
399 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
400 require C<search_literal>.
405 my ($self, $sql, @bind) = @_;
407 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
410 return $self->search(\[ $sql, map [ __DUMMY__ => $_ ], @bind ], ($attr || () ));
417 =item Arguments: @values | \%cols, \%attrs?
419 =item Return Value: $row_object | undef
423 Finds a row based on its primary key or unique constraint. For example, to find
424 a row by its primary key:
426 my $cd = $schema->resultset('CD')->find(5);
428 You can also find a row by a specific unique constraint using the C<key>
429 attribute. For example:
431 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
432 key => 'cd_artist_title'
435 Additionally, you can specify the columns explicitly by name:
437 my $cd = $schema->resultset('CD')->find(
439 artist => 'Massive Attack',
440 title => 'Mezzanine',
442 { key => 'cd_artist_title' }
445 If the C<key> is specified as C<primary>, it searches only on the primary key.
447 If no C<key> is specified, it searches on all unique constraints defined on the
448 source for which column data is provided, including the primary key.
450 If your table does not have a primary key, you B<must> provide a value for the
451 C<key> attribute matching one of the unique constraints on the source.
453 In addition to C<key>, L</find> recognizes and applies standard
454 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
456 Note: If your query does not return only one row, a warning is generated:
458 Query returned more than one row
460 See also L</find_or_create> and L</update_or_create>. For information on how to
461 declare unique constraints, see
462 L<DBIx::Class::ResultSource/add_unique_constraint>.
468 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
470 # Default to the primary key, but allow a specific key
471 my @cols = exists $attrs->{key}
472 ? $self->result_source->unique_constraint_columns($attrs->{key})
473 : $self->result_source->primary_columns;
474 $self->throw_exception(
475 "Can't find unless a primary key is defined or unique constraint is specified"
478 # Parse out a hashref from input
480 if (ref $_[0] eq 'HASH') {
481 $input_query = { %{$_[0]} };
483 elsif (@_ == @cols) {
485 @{$input_query}{@cols} = @_;
488 # Compatibility: Allow e.g. find(id => $value)
489 carp "Find by key => value deprecated; please use a hashref instead";
493 my (%related, $info);
495 KEY: foreach my $key (keys %$input_query) {
496 if (ref($input_query->{$key})
497 && ($info = $self->result_source->relationship_info($key))) {
498 my $val = delete $input_query->{$key};
499 next KEY if (ref($val) eq 'ARRAY'); # has_many for multi_create
500 my $rel_q = $self->result_source->_resolve_condition(
501 $info->{cond}, $val, $key
503 die "Can't handle OR join condition in find" if ref($rel_q) eq 'ARRAY';
504 @related{keys %$rel_q} = values %$rel_q;
507 if (my @keys = keys %related) {
508 @{$input_query}{@keys} = values %related;
512 # Build the final query: Default to the disjunction of the unique queries,
513 # but allow the input query in case the ResultSet defines the query or the
514 # user is abusing find
515 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
517 if (exists $attrs->{key}) {
518 my @unique_cols = $self->result_source->unique_constraint_columns($attrs->{key});
519 my $unique_query = $self->_build_unique_query($input_query, \@unique_cols);
520 $query = $self->_add_alias($unique_query, $alias);
522 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
523 # This means that we got here after a merger of relationship conditions
524 # in ::Relationship::Base::search_related (the row method), and furthermore
525 # the relationship is of the 'single' type. This means that the condition
526 # provided by the relationship (already attached to $self) is sufficient,
527 # as there can be only one row in the database that would satisfy the
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);
538 my $rs = $self->search ($query, {result_class => $self->result_class, %$attrs});
539 if ($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 unique constraints.
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?
685 my $cd = $schema->resultset('CD')->single({ year => 2001 });
687 Inflates the first result without creating a cursor if the resultset has
688 any records in it; if not returns nothing. Used by L</find> as a lean version of
691 While this method can take an optional search condition (just like L</search>)
692 being a fast-code-path it does not recognize search attributes. If you need to
693 add extra joins or similar, call L</search> and then chain-call L</single> on the
694 L<DBIx::Class::ResultSet> returned.
700 As of 0.08100, this method enforces the assumption that the preceding
701 query returns only one row. If more than one row is returned, you will receive
704 Query returned more than one row
706 In this case, you should be using L</next> or L</find> instead, or if you really
707 know what you are doing, use the L</rows> attribute to explicitly limit the size
710 This method will also throw an exception if it is called on a resultset prefetching
711 has_many, as such a prefetch implies fetching multiple rows from the database in
712 order to assemble the resulting object.
719 my ($self, $where) = @_;
721 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
724 my $attrs = $self->_resolved_attrs_copy;
726 if ($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} = $where;
744 # XXX: Disabled since it doesn't infer uniqueness in all cases
745 # unless ($self->_is_unique_query($attrs->{where})) {
746 # carp "Query not guaranteed to return a single row"
747 # . "; please declare your unique constraints or use search instead";
750 my @data = $self->result_source->storage->select_single(
751 $attrs->{from}, $attrs->{select},
752 $attrs->{where}, $attrs
755 return (@data ? ($self->_construct_object(@data))[0] : undef);
761 # Try to determine if the specified query is guaranteed to be unique, based on
762 # the declared unique constraints.
764 sub _is_unique_query {
765 my ($self, $query) = @_;
767 my $collapsed = $self->_collapse_query($query);
768 my $alias = $self->{attrs}{alias};
770 foreach my $name ($self->result_source->unique_constraint_names) {
771 my @unique_cols = map {
773 } $self->result_source->unique_constraint_columns($name);
775 # Count the values for each unique column
776 my %seen = map { $_ => 0 } @unique_cols;
778 foreach my $key (keys %$collapsed) {
779 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
780 next unless exists $seen{$aliased}; # Additional constraints are okay
781 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
784 # If we get 0 or more than 1 value for a column, it's not necessarily unique
785 return 1 unless grep { $_ != 1 } values %seen;
793 # Recursively collapse the query, accumulating values for each column.
795 sub _collapse_query {
796 my ($self, $query, $collapsed) = @_;
800 if (ref $query eq 'ARRAY') {
801 foreach my $subquery (@$query) {
802 next unless ref $subquery; # -or
803 $collapsed = $self->_collapse_query($subquery, $collapsed);
806 elsif (ref $query eq 'HASH') {
807 if (keys %$query and (keys %$query)[0] eq '-and') {
808 foreach my $subquery (@{$query->{-and}}) {
809 $collapsed = $self->_collapse_query($subquery, $collapsed);
813 foreach my $col (keys %$query) {
814 my $value = $query->{$col};
815 $collapsed->{$col}{$value}++;
827 =item Arguments: $cond?
829 =item Return Value: $resultsetcolumn
833 my $max_length = $rs->get_column('length')->max;
835 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
840 my ($self, $column) = @_;
841 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
849 =item Arguments: $cond, \%attrs?
851 =item Return Value: $resultset (scalar context), @row_objs (list context)
855 # WHERE title LIKE '%blue%'
856 $cd_rs = $rs->search_like({ title => '%blue%'});
858 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
859 that this is simply a convenience method retained for ex Class::DBI users.
860 You most likely want to use L</search> with specific operators.
862 For more information, see L<DBIx::Class::Manual::Cookbook>.
864 This method is deprecated and will be removed in 0.09. Use L</search()>
865 instead. An example conversion is:
867 ->search_like({ foo => 'bar' });
871 ->search({ foo => { like => 'bar' } });
878 'search_like() is deprecated and will be removed in DBIC version 0.09.'
879 .' Instead use ->search({ x => { -like => "y%" } })'
880 .' (note the outer pair of {}s - they are important!)'
882 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
883 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
884 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
885 return $class->search($query, { %$attrs });
892 =item Arguments: $first, $last
894 =item Return Value: $resultset (scalar context), @row_objs (list context)
898 Returns a resultset or object list representing a subset of elements from the
899 resultset slice is called on. Indexes are from 0, i.e., to get the first
902 my ($one, $two, $three) = $rs->slice(0, 2);
907 my ($self, $min, $max) = @_;
908 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
909 $attrs->{offset} = $self->{attrs}{offset} || 0;
910 $attrs->{offset} += $min;
911 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
912 return $self->search(undef(), $attrs);
913 #my $slice = (ref $self)->new($self->result_source, $attrs);
914 #return (wantarray ? $slice->all : $slice);
921 =item Arguments: none
923 =item Return Value: $result?
927 Returns the next element in the resultset (C<undef> is there is none).
929 Can be used to efficiently iterate over records in the resultset:
931 my $rs = $schema->resultset('CD')->search;
932 while (my $cd = $rs->next) {
936 Note that you need to store the resultset object, and call C<next> on it.
937 Calling C<< resultset('Table')->next >> repeatedly will always return the
938 first record from the resultset.
944 if (my $cache = $self->get_cache) {
945 $self->{all_cache_position} ||= 0;
946 return $cache->[$self->{all_cache_position}++];
948 if ($self->{attrs}{cache}) {
949 $self->{all_cache_position} = 1;
950 return ($self->all)[0];
952 if ($self->{stashed_objects}) {
953 my $obj = shift(@{$self->{stashed_objects}});
954 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
958 exists $self->{stashed_row}
959 ? @{delete $self->{stashed_row}}
960 : $self->cursor->next
962 return undef unless (@row);
963 my ($row, @more) = $self->_construct_object(@row);
964 $self->{stashed_objects} = \@more if @more;
968 sub _construct_object {
969 my ($self, @row) = @_;
971 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row)
973 my @new = $self->result_class->inflate_result($self->result_source, @$info);
974 @new = $self->{_attrs}{record_filter}->(@new)
975 if exists $self->{_attrs}{record_filter};
979 # two arguments: $as_proto is an arrayref of column names,
980 # $row_ref is an arrayref of the data. If none of the row data
981 # is defined we return undef (that's copied from the old
982 # _collapse_result). Next we decide whether we need to collapse
983 # the resultset (i.e. we prefetch something) or not. $collapse
984 # indicates that. The do-while loop will run once if we do not need
985 # to collapse the result and will run as long as _merge_result returns
986 # a true value. It will return undef if the current added row does not
987 # match the previous row. A bit of stashing and cursor magic is
988 # required so that the cursor is not mixed up.
990 # "$rows" is a bit misleading. In the end, there should only be one
991 # element in this arrayref.
993 sub _collapse_result {
994 my ( $self, $as_proto, $row_ref ) = @_;
1002 return undef unless $has_def;
1004 my $collapse = $self->_resolved_attrs->{collapse};
1006 my @row = @$row_ref;
1009 my $row = { map { $_ => $row[ $i++ ] } @$as_proto };
1010 $row = $self->result_source->_parse_row($row, $collapse);
1011 unless ( scalar @$rows ) {
1012 push( @$rows, $row );
1014 $collapse = undef unless ( $self->_merge_result( $rows, $row ) );
1017 && do { @row = $self->cursor->next; $self->{stashed_row} = \@row if @row; }
1024 # _merge_result accepts an arrayref of rows objects (again, an arrayref of two elements)
1025 # and a row object which should be merged into the first object.
1026 # First we try to find out whether $row is already in $rows. If this is the case
1027 # we try to merge them by iteration through their relationship data. We call
1028 # _merge_result again on them, so they get merged.
1030 # If we don't find the $row in $rows, we append it to $rows and return undef.
1031 # _merge_result returns 1 otherwise (i.e. $row has been found in $rows).
1034 my ( $self, $rows, $row ) = @_;
1035 my ( $columns, $rels ) = @$row;
1037 foreach my $seen (@$rows) {
1039 foreach my $column ( keys %$columns ) {
1040 if ( defined $seen->[0]->{$column} ^ defined $columns->{$column}
1041 or defined $columns->{$column}
1042 && $seen->[0]->{$column} ne $columns->{$column} )
1055 foreach my $rel ( keys %$rels ) {
1056 my $old_rows = $found->[1]->{$rel};
1057 $self->_merge_result(
1058 ref $found->[1]->{$rel}->[0] eq 'HASH' ? [ $found->[1]->{$rel} ]
1059 : $found->[1]->{$rel},
1060 ref $rels->{$rel}->[0] eq 'HASH' ? [ $rels->{$rel}->[0], $rels->{$rel}->[1] ]
1061 : $rels->{$rel}->[0]
1068 push( @$rows, $row );
1076 =head2 result_source
1080 =item Arguments: $result_source?
1082 =item Return Value: $result_source
1086 An accessor for the primary ResultSource object from which this ResultSet
1093 =item Arguments: $result_class?
1095 =item Return Value: $result_class
1099 An accessor for the class to use when creating row objects. Defaults to
1100 C<< result_source->result_class >> - which in most cases is the name of the
1101 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1103 Note that changing the result_class will also remove any components
1104 that were originally loaded in the source class via
1105 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1106 in the original source class will not run.
1111 my ($self, $result_class) = @_;
1112 if ($result_class) {
1113 $self->ensure_class_loaded($result_class);
1114 $self->_result_class($result_class);
1115 $self->{attrs}{result_class} = $result_class if ref $self;
1117 $self->_result_class;
1124 =item Arguments: $cond, \%attrs??
1126 =item Return Value: $count
1130 Performs an SQL C<COUNT> with the same query as the resultset was built
1131 with to find the number of elements. Passing arguments is equivalent to
1132 C<< $rs->search ($cond, \%attrs)->count >>
1138 return $self->search(@_)->count if @_ and defined $_[0];
1139 return scalar @{ $self->get_cache } if $self->get_cache;
1141 my $attrs = $self->_resolved_attrs_copy;
1143 # this is a little optimization - it is faster to do the limit
1144 # adjustments in software, instead of a subquery
1145 my $rows = delete $attrs->{rows};
1146 my $offset = delete $attrs->{offset};
1149 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1150 $crs = $self->_count_subq_rs ($attrs);
1153 $crs = $self->_count_rs ($attrs);
1155 my $count = $crs->next;
1157 $count -= $offset if $offset;
1158 $count = $rows if $rows and $rows < $count;
1159 $count = 0 if ($count < 0);
1168 =item Arguments: $cond, \%attrs??
1170 =item Return Value: $count_rs
1174 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1175 This can be very handy for subqueries:
1177 ->search( { amount => $some_rs->count_rs->as_query } )
1179 As with regular resultsets the SQL query will be executed only after
1180 the resultset is accessed via L</next> or L</all>. That would return
1181 the same single value obtainable via L</count>.
1187 return $self->search(@_)->count_rs if @_;
1189 # this may look like a lack of abstraction (count() does about the same)
1190 # but in fact an _rs *must* use a subquery for the limits, as the
1191 # software based limiting can not be ported if this $rs is to be used
1192 # in a subquery itself (i.e. ->as_query)
1193 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1194 return $self->_count_subq_rs;
1197 return $self->_count_rs;
1202 # returns a ResultSetColumn object tied to the count query
1205 my ($self, $attrs) = @_;
1207 my $rsrc = $self->result_source;
1208 $attrs ||= $self->_resolved_attrs;
1210 my $tmp_attrs = { %$attrs };
1212 # take off any limits, record_filter is cdbi, and no point of ordering a count
1213 delete $tmp_attrs->{$_} for (qw/select as rows offset order_by record_filter/);
1215 # overwrite the selector (supplied by the storage)
1216 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $tmp_attrs);
1217 $tmp_attrs->{as} = 'count';
1219 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1225 # same as above but uses a subquery
1227 sub _count_subq_rs {
1228 my ($self, $attrs) = @_;
1230 my $rsrc = $self->result_source;
1231 $attrs ||= $self->_resolved_attrs_copy;
1233 my $sub_attrs = { %$attrs };
1235 # extra selectors do not go in the subquery and there is no point of ordering it
1236 delete $sub_attrs->{$_} for qw/collapse select _prefetch_select as order_by/;
1238 # if we multi-prefetch we group_by primary keys only as this is what we would
1239 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1240 if ( $attrs->{collapse} ) {
1241 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } ($rsrc->_pri_cols) ]
1244 $sub_attrs->{select} = $rsrc->storage->_subq_count_select ($rsrc, $attrs);
1246 # this is so that the query can be simplified e.g.
1247 # * ordering can be thrown away in things like Top limit
1248 $sub_attrs->{-for_count_only} = 1;
1250 my $sub_rs = $rsrc->resultset_class->new ($rsrc, $sub_attrs);
1253 -alias => 'count_subq',
1254 -source_handle => $rsrc->handle,
1255 count_subq => $sub_rs->as_query,
1258 # the subquery replaces this
1259 delete $attrs->{$_} for qw/where bind collapse group_by having having_bind rows offset/;
1261 return $self->_count_rs ($attrs);
1268 =head2 count_literal
1272 =item Arguments: $sql_fragment, @bind_values
1274 =item Return Value: $count
1278 Counts the results in a literal query. Equivalent to calling L</search_literal>
1279 with the passed arguments, then L</count>.
1283 sub count_literal { shift->search_literal(@_)->count; }
1289 =item Arguments: none
1291 =item Return Value: @objects
1295 Returns all elements in the resultset. Called implicitly if the resultset
1296 is returned in list context.
1303 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1306 return @{ $self->get_cache } if $self->get_cache;
1310 if ($self->_resolved_attrs->{collapse}) {
1311 # Using $self->cursor->all is really just an optimisation.
1312 # If we're collapsing has_many prefetches it probably makes
1313 # very little difference, and this is cleaner than hacking
1314 # _construct_object to survive the approach
1315 $self->cursor->reset;
1316 my @row = $self->cursor->next;
1318 push(@obj, $self->_construct_object(@row));
1319 @row = (exists $self->{stashed_row}
1320 ? @{delete $self->{stashed_row}}
1321 : $self->cursor->next);
1324 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1327 $self->set_cache(\@obj) if $self->{attrs}{cache};
1336 =item Arguments: none
1338 =item Return Value: $self
1342 Resets the resultset's cursor, so you can iterate through the elements again.
1343 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1350 delete $self->{_attrs} if exists $self->{_attrs};
1351 $self->{all_cache_position} = 0;
1352 $self->cursor->reset;
1360 =item Arguments: none
1362 =item Return Value: $object?
1366 Resets the resultset and returns an object for the first result (if the
1367 resultset returns anything).
1372 return $_[0]->reset->next;
1378 # Determines whether and what type of subquery is required for the $rs operation.
1379 # If grouping is necessary either supplies its own, or verifies the current one
1380 # After all is done delegates to the proper storage method.
1382 sub _rs_update_delete {
1383 my ($self, $op, $values) = @_;
1385 my $rsrc = $self->result_source;
1387 # if a condition exists we need to strip all table qualifiers
1388 # if this is not possible we'll force a subquery below
1389 my $cond = $rsrc->schema->storage->_strip_cond_qualifiers ($self->{cond});
1391 my $needs_group_by_subq = $self->_has_resolved_attr (qw/collapse group_by -join/);
1392 my $needs_subq = $needs_group_by_subq || (not defined $cond) || $self->_has_resolved_attr(qw/row offset/);
1394 if ($needs_group_by_subq or $needs_subq) {
1396 # make a new $rs selecting only the PKs (that's all we really need)
1397 my $attrs = $self->_resolved_attrs_copy;
1399 delete $attrs->{$_} for qw/collapse select as/;
1400 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->_pri_cols) ];
1402 if ($needs_group_by_subq) {
1403 # make sure no group_by was supplied, or if there is one - make sure it matches
1404 # the columns compiled above perfectly. Anything else can not be sanely executed
1405 # on most databases so croak right then and there
1407 if (my $g = $attrs->{group_by}) {
1408 my @current_group_by = map
1409 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1414 join ("\x00", sort @current_group_by)
1416 join ("\x00", sort @{$attrs->{columns}} )
1418 $self->throw_exception (
1419 "You have just attempted a $op operation on a resultset which does group_by"
1420 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1421 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1422 . ' kind of queries. Please retry the operation with a modified group_by or'
1423 . ' without using one at all.'
1428 $attrs->{group_by} = $attrs->{columns};
1432 my $subrs = (ref $self)->new($rsrc, $attrs);
1434 return $self->result_source->storage->_subq_update_delete($subrs, $op, $values);
1437 return $rsrc->storage->$op(
1439 $op eq 'update' ? $values : (),
1449 =item Arguments: \%values
1451 =item Return Value: $storage_rv
1455 Sets the specified columns in the resultset to the supplied values in a
1456 single query. Return value will be true if the update succeeded or false
1457 if no records were updated; exact type of success value is storage-dependent.
1462 my ($self, $values) = @_;
1463 $self->throw_exception('Values for update must be a hash')
1464 unless ref $values eq 'HASH';
1466 return $self->_rs_update_delete ('update', $values);
1473 =item Arguments: \%values
1475 =item Return Value: 1
1479 Fetches all objects and updates them one at a time. Note that C<update_all>
1480 will run DBIC cascade triggers, while L</update> will not.
1485 my ($self, $values) = @_;
1486 $self->throw_exception('Values for update_all must be a hash')
1487 unless ref $values eq 'HASH';
1488 foreach my $obj ($self->all) {
1489 $obj->set_columns($values)->update;
1498 =item Arguments: none
1500 =item Return Value: $storage_rv
1504 Deletes the contents of the resultset from its result source. Note that this
1505 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1506 to run. See also L<DBIx::Class::Row/delete>.
1508 Return value will be the amount of rows deleted; exact type of return value
1509 is storage-dependent.
1515 $self->throw_exception('delete does not accept any arguments')
1518 return $self->_rs_update_delete ('delete');
1525 =item Arguments: none
1527 =item Return Value: 1
1531 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1532 will run DBIC cascade triggers, while L</delete> will not.
1538 $self->throw_exception('delete_all does not accept any arguments')
1541 $_->delete for $self->all;
1549 =item Arguments: \@data;
1553 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1554 For the arrayref of hashrefs style each hashref should be a structure suitable
1555 forsubmitting to a $resultset->create(...) method.
1557 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1558 to insert the data, as this is a faster method.
1560 Otherwise, each set of data is inserted into the database using
1561 L<DBIx::Class::ResultSet/create>, and the resulting objects are
1562 accumulated into an array. The array itself, or an array reference
1563 is returned depending on scalar or list context.
1565 Example: Assuming an Artist Class that has many CDs Classes relating:
1567 my $Artist_rs = $schema->resultset("Artist");
1569 ## Void Context Example
1570 $Artist_rs->populate([
1571 { artistid => 4, name => 'Manufactured Crap', cds => [
1572 { title => 'My First CD', year => 2006 },
1573 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1576 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1577 { title => 'My parents sold me to a record company', year => 2005 },
1578 { title => 'Why Am I So Ugly?', year => 2006 },
1579 { title => 'I Got Surgery and am now Popular', year => 2007 }
1584 ## Array Context Example
1585 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1586 { name => "Artist One"},
1587 { name => "Artist Two"},
1588 { name => "Artist Three", cds=> [
1589 { title => "First CD", year => 2007},
1590 { title => "Second CD", year => 2008},
1594 print $ArtistOne->name; ## response is 'Artist One'
1595 print $ArtistThree->cds->count ## reponse is '2'
1597 For the arrayref of arrayrefs style, the first element should be a list of the
1598 fieldsnames to which the remaining elements are rows being inserted. For
1601 $Arstist_rs->populate([
1602 [qw/artistid name/],
1603 [100, 'A Formally Unknown Singer'],
1604 [101, 'A singer that jumped the shark two albums ago'],
1605 [102, 'An actually cool singer'],
1608 Please note an important effect on your data when choosing between void and
1609 wantarray context. Since void context goes straight to C<insert_bulk> in
1610 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
1611 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
1612 create primary keys for you, you will find that your PKs are empty. In this
1613 case you will have to use the wantarray context in order to create those
1621 # cruft placed in standalone method
1622 my $data = $self->_normalize_populate_args(@_);
1624 if(defined wantarray) {
1626 foreach my $item (@$data) {
1627 push(@created, $self->create($item));
1629 return wantarray ? @created : \@created;
1631 my $first = $data->[0];
1633 # if a column is a registered relationship, and is a non-blessed hash/array, consider
1634 # it relationship data
1635 my (@rels, @columns);
1636 for (keys %$first) {
1637 my $ref = ref $first->{$_};
1638 $self->result_source->has_relationship($_) && ($ref eq 'ARRAY' or $ref eq 'HASH')
1644 my @pks = $self->result_source->primary_columns;
1646 ## do the belongs_to relationships
1647 foreach my $index (0..$#$data) {
1649 # delegate to create() for any dataset without primary keys with specified relationships
1650 if (grep { !defined $data->[$index]->{$_} } @pks ) {
1652 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
1653 my @ret = $self->populate($data);
1659 foreach my $rel (@rels) {
1660 next unless ref $data->[$index]->{$rel} eq "HASH";
1661 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1662 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1663 my $related = $result->result_source->_resolve_condition(
1664 $result->result_source->relationship_info($reverse)->{cond},
1669 delete $data->[$index]->{$rel};
1670 $data->[$index] = {%{$data->[$index]}, %$related};
1672 push @columns, keys %$related if $index == 0;
1676 ## inherit the data locked in the conditions of the resultset
1677 my ($rs_data) = $self->_merge_cond_with_data({});
1678 delete @{$rs_data}{@columns};
1679 my @inherit_cols = keys %$rs_data;
1680 my @inherit_data = values %$rs_data;
1682 ## do bulk insert on current row
1683 $self->result_source->storage->insert_bulk(
1684 $self->result_source,
1685 [@columns, @inherit_cols],
1686 [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
1689 ## do the has_many relationships
1690 foreach my $item (@$data) {
1692 foreach my $rel (@rels) {
1693 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1695 my $parent = $self->find({map { $_ => $item->{$_} } @pks})
1696 || $self->throw_exception('Cannot find the relating object.');
1698 my $child = $parent->$rel;
1700 my $related = $child->result_source->_resolve_condition(
1701 $parent->result_source->relationship_info($rel)->{cond},
1706 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1707 my @populate = map { {%$_, %$related} } @rows_to_add;
1709 $child->populate( \@populate );
1716 # populate() argumnets went over several incarnations
1717 # What we ultimately support is AoH
1718 sub _normalize_populate_args {
1719 my ($self, $arg) = @_;
1721 if (ref $arg eq 'ARRAY') {
1722 if (ref $arg->[0] eq 'HASH') {
1725 elsif (ref $arg->[0] eq 'ARRAY') {
1727 my @colnames = @{$arg->[0]};
1728 foreach my $values (@{$arg}[1 .. $#$arg]) {
1729 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
1735 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
1742 =item Arguments: none
1744 =item Return Value: $pager
1748 Return Value a L<Data::Page> object for the current resultset. Only makes
1749 sense for queries with a C<page> attribute.
1751 To get the full count of entries for a paged resultset, call
1752 C<total_entries> on the L<Data::Page> object.
1759 return $self->{pager} if $self->{pager};
1761 my $attrs = $self->{attrs};
1762 $self->throw_exception("Can't create pager for non-paged rs")
1763 unless $self->{attrs}{page};
1764 $attrs->{rows} ||= 10;
1766 # throw away the paging flags and re-run the count (possibly
1767 # with a subselect) to get the real total count
1768 my $count_attrs = { %$attrs };
1769 delete $count_attrs->{$_} for qw/rows offset page pager/;
1770 my $total_count = (ref $self)->new($self->result_source, $count_attrs)->count;
1772 return $self->{pager} = Data::Page->new(
1775 $self->{attrs}{page}
1783 =item Arguments: $page_number
1785 =item Return Value: $rs
1789 Returns a resultset for the $page_number page of the resultset on which page
1790 is called, where each page contains a number of rows equal to the 'rows'
1791 attribute set on the resultset (10 by default).
1796 my ($self, $page) = @_;
1797 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1804 =item Arguments: \%vals
1806 =item Return Value: $rowobject
1810 Creates a new row object in the resultset's result class and returns
1811 it. The row is not inserted into the database at this point, call
1812 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
1813 will tell you whether the row object has been inserted or not.
1815 Passes the hashref of input on to L<DBIx::Class::Row/new>.
1820 my ($self, $values) = @_;
1821 $self->throw_exception( "new_result needs a hash" )
1822 unless (ref $values eq 'HASH');
1824 my ($merged_cond, $cols_from_relations) = $self->_merge_cond_with_data($values);
1828 @$cols_from_relations
1829 ? (-cols_from_relations => $cols_from_relations)
1831 -source_handle => $self->_source_handle,
1832 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
1835 return $self->result_class->new(\%new);
1838 # _merge_cond_with_data
1840 # Takes a simple hash of K/V data and returns its copy merged with the
1841 # condition already present on the resultset. Additionally returns an
1842 # arrayref of value/condition names, which were inferred from related
1843 # objects (this is needed for in-memory related objects)
1844 sub _merge_cond_with_data {
1845 my ($self, $data) = @_;
1847 my (%new_data, @cols_from_relations);
1849 my $alias = $self->{attrs}{alias};
1851 if (! defined $self->{cond}) {
1852 # just massage $data below
1854 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
1855 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
1856 @cols_from_relations = keys %new_data;
1858 elsif (ref $self->{cond} ne 'HASH') {
1859 $self->throw_exception(
1860 "Can't abstract implicit construct, resultset condition not a hash"
1864 # precendence must be given to passed values over values inherited from
1865 # the cond, so the order here is important.
1866 my $collapsed_cond = $self->_collapse_cond($self->{cond});
1867 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
1869 while ( my($col, $value) = each %implied ) {
1870 if (ref($value) eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '=') {
1871 $new_data{$col} = $value->{'='};
1874 $new_data{$col} = $value if $self->_is_deterministic_value($value);
1880 %{ $self->_remove_alias($data, $alias) },
1883 return (\%new_data, \@cols_from_relations);
1886 # _is_deterministic_value
1888 # Make an effor to strip non-deterministic values from the condition,
1889 # to make sure new_result chokes less
1891 sub _is_deterministic_value {
1894 my $ref_type = ref $value;
1895 return 1 if $ref_type eq '' || $ref_type eq 'SCALAR';
1896 return 1 if Scalar::Util::blessed($value);
1900 # _has_resolved_attr
1902 # determines if the resultset defines at least one
1903 # of the attributes supplied
1905 # used to determine if a subquery is neccessary
1907 # supports some virtual attributes:
1909 # This will scan for any joins being present on the resultset.
1910 # It is not a mere key-search but a deep inspection of {from}
1913 sub _has_resolved_attr {
1914 my ($self, @attr_names) = @_;
1916 my $attrs = $self->_resolved_attrs;
1920 for my $n (@attr_names) {
1921 if (grep { $n eq $_ } (qw/-join/) ) {
1922 $extra_checks{$n}++;
1926 my $attr = $attrs->{$n};
1928 next if not defined $attr;
1930 if (ref $attr eq 'HASH') {
1931 return 1 if keys %$attr;
1933 elsif (ref $attr eq 'ARRAY') {
1941 # a resolved join is expressed as a multi-level from
1943 $extra_checks{-join}
1945 ref $attrs->{from} eq 'ARRAY'
1947 @{$attrs->{from}} > 1
1955 # Recursively collapse the condition.
1957 sub _collapse_cond {
1958 my ($self, $cond, $collapsed) = @_;
1962 if (ref $cond eq 'ARRAY') {
1963 foreach my $subcond (@$cond) {
1964 next unless ref $subcond; # -or
1965 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1968 elsif (ref $cond eq 'HASH') {
1969 if (keys %$cond and (keys %$cond)[0] eq '-and') {
1970 foreach my $subcond (@{$cond->{-and}}) {
1971 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1975 foreach my $col (keys %$cond) {
1976 my $value = $cond->{$col};
1977 $collapsed->{$col} = $value;
1987 # Remove the specified alias from the specified query hash. A copy is made so
1988 # the original query is not modified.
1991 my ($self, $query, $alias) = @_;
1993 my %orig = %{ $query || {} };
1996 foreach my $key (keys %orig) {
1998 $unaliased{$key} = $orig{$key};
2001 $unaliased{$1} = $orig{$key}
2002 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2012 =item Arguments: none
2014 =item Return Value: \[ $sql, @bind ]
2018 Returns the SQL query and bind vars associated with the invocant.
2020 This is generally used as the RHS for a subquery.
2027 my $attrs = $self->_resolved_attrs_copy;
2032 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2033 # $sql also has no wrapping parenthesis in list ctx
2035 my $sqlbind = $self->result_source->storage
2036 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2045 =item Arguments: \%vals, \%attrs?
2047 =item Return Value: $rowobject
2051 my $artist = $schema->resultset('Artist')->find_or_new(
2052 { artist => 'fred' }, { key => 'artists' });
2054 $cd->cd_to_producer->find_or_new({ producer => $producer },
2055 { key => 'primary });
2057 Find an existing record from this resultset, based on its primary
2058 key, or a unique constraint. If none exists, instantiate a new result
2059 object and return it. The object will not be saved into your storage
2060 until you call L<DBIx::Class::Row/insert> on it.
2062 You most likely want this method when looking for existing rows using
2063 a unique constraint that is not the primary key, or looking for
2066 If you want objects to be saved immediately, use L</find_or_create>
2069 B<Note>: Take care when using C<find_or_new> with a table having
2070 columns with default values that you intend to be automatically
2071 supplied by the database (e.g. an auto_increment primary key column).
2072 In normal usage, the value of such columns should NOT be included at
2073 all in the call to C<find_or_new>, even when set to C<undef>.
2079 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2080 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2081 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2084 return $self->new_result($hash);
2091 =item Arguments: \%vals
2093 =item Return Value: a L<DBIx::Class::Row> $object
2097 Attempt to create a single new row or a row with multiple related rows
2098 in the table represented by the resultset (and related tables). This
2099 will not check for duplicate rows before inserting, use
2100 L</find_or_create> to do that.
2102 To create one row for this resultset, pass a hashref of key/value
2103 pairs representing the columns of the table and the values you wish to
2104 store. If the appropriate relationships are set up, foreign key fields
2105 can also be passed an object representing the foreign row, and the
2106 value will be set to its primary key.
2108 To create related objects, pass a hashref of related-object column values
2109 B<keyed on the relationship name>. If the relationship is of type C<multi>
2110 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2111 The process will correctly identify columns holding foreign keys, and will
2112 transparently populate them from the keys of the corresponding relation.
2113 This can be applied recursively, and will work correctly for a structure
2114 with an arbitrary depth and width, as long as the relationships actually
2115 exists and the correct column data has been supplied.
2118 Instead of hashrefs of plain related data (key/value pairs), you may
2119 also pass new or inserted objects. New objects (not inserted yet, see
2120 L</new>), will be inserted into their appropriate tables.
2122 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2124 Example of creating a new row.
2126 $person_rs->create({
2127 name=>"Some Person",
2128 email=>"somebody@someplace.com"
2131 Example of creating a new row and also creating rows in a related C<has_many>
2132 or C<has_one> resultset. Note Arrayref.
2135 { artistid => 4, name => 'Manufactured Crap', cds => [
2136 { title => 'My First CD', year => 2006 },
2137 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2142 Example of creating a new row and also creating a row in a related
2143 C<belongs_to>resultset. Note Hashref.
2146 title=>"Music for Silly Walks",
2149 name=>"Silly Musician",
2157 When subclassing ResultSet never attempt to override this method. Since
2158 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2159 lot of the internals simply never call it, so your override will be
2160 bypassed more often than not. Override either L<new|DBIx::Class::Row/new>
2161 or L<insert|DBIx::Class::Row/insert> depending on how early in the
2162 L</create> process you need to intervene.
2169 my ($self, $attrs) = @_;
2170 $self->throw_exception( "create needs a hashref" )
2171 unless ref $attrs eq 'HASH';
2172 return $self->new_result($attrs)->insert;
2175 =head2 find_or_create
2179 =item Arguments: \%vals, \%attrs?
2181 =item Return Value: $rowobject
2185 $cd->cd_to_producer->find_or_create({ producer => $producer },
2186 { key => 'primary' });
2188 Tries to find a record based on its primary key or unique constraints; if none
2189 is found, creates one and returns that instead.
2191 my $cd = $schema->resultset('CD')->find_or_create({
2193 artist => 'Massive Attack',
2194 title => 'Mezzanine',
2198 Also takes an optional C<key> attribute, to search by a specific key or unique
2199 constraint. For example:
2201 my $cd = $schema->resultset('CD')->find_or_create(
2203 artist => 'Massive Attack',
2204 title => 'Mezzanine',
2206 { key => 'cd_artist_title' }
2209 B<Note>: Because find_or_create() reads from the database and then
2210 possibly inserts based on the result, this method is subject to a race
2211 condition. Another process could create a record in the table after
2212 the find has completed and before the create has started. To avoid
2213 this problem, use find_or_create() inside a transaction.
2215 B<Note>: Take care when using C<find_or_create> with a table having
2216 columns with default values that you intend to be automatically
2217 supplied by the database (e.g. an auto_increment primary key column).
2218 In normal usage, the value of such columns should NOT be included at
2219 all in the call to C<find_or_create>, even when set to C<undef>.
2221 See also L</find> and L</update_or_create>. For information on how to declare
2222 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2226 sub find_or_create {
2228 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2229 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2230 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2233 return $self->create($hash);
2236 =head2 update_or_create
2240 =item Arguments: \%col_values, { key => $unique_constraint }?
2242 =item Return Value: $rowobject
2246 $resultset->update_or_create({ col => $val, ... });
2248 First, searches for an existing row matching one of the unique constraints
2249 (including the primary key) on the source of this resultset. If a row is
2250 found, updates it with the other given column values. Otherwise, creates a new
2253 Takes an optional C<key> attribute to search on a specific unique constraint.
2256 # In your application
2257 my $cd = $schema->resultset('CD')->update_or_create(
2259 artist => 'Massive Attack',
2260 title => 'Mezzanine',
2263 { key => 'cd_artist_title' }
2266 $cd->cd_to_producer->update_or_create({
2267 producer => $producer,
2274 If no C<key> is specified, it searches on all unique constraints defined on the
2275 source, including the primary key.
2277 If the C<key> is specified as C<primary>, it searches only on the primary key.
2279 See also L</find> and L</find_or_create>. For information on how to declare
2280 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2282 B<Note>: Take care when using C<update_or_create> with a table having
2283 columns with default values that you intend to be automatically
2284 supplied by the database (e.g. an auto_increment primary key column).
2285 In normal usage, the value of such columns should NOT be included at
2286 all in the call to C<update_or_create>, even when set to C<undef>.
2290 sub update_or_create {
2292 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2293 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2295 my $row = $self->find($cond, $attrs);
2297 $row->update($cond);
2301 return $self->create($cond);
2304 =head2 update_or_new
2308 =item Arguments: \%col_values, { key => $unique_constraint }?
2310 =item Return Value: $rowobject
2314 $resultset->update_or_new({ col => $val, ... });
2316 First, searches for an existing row matching one of the unique constraints
2317 (including the primary key) on the source of this resultset. If a row is
2318 found, updates it with the other given column values. Otherwise, instantiate
2319 a new result object and return it. The object will not be saved into your storage
2320 until you call L<DBIx::Class::Row/insert> on it.
2322 Takes an optional C<key> attribute to search on a specific unique constraint.
2325 # In your application
2326 my $cd = $schema->resultset('CD')->update_or_new(
2328 artist => 'Massive Attack',
2329 title => 'Mezzanine',
2332 { key => 'cd_artist_title' }
2335 if ($cd->in_storage) {
2336 # the cd was updated
2339 # the cd is not yet in the database, let's insert it
2343 B<Note>: Take care when using C<update_or_new> with a table having
2344 columns with default values that you intend to be automatically
2345 supplied by the database (e.g. an auto_increment primary key column).
2346 In normal usage, the value of such columns should NOT be included at
2347 all in the call to C<update_or_new>, even when set to C<undef>.
2349 See also L</find>, L</find_or_create> and L</find_or_new>.
2355 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2356 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2358 my $row = $self->find( $cond, $attrs );
2359 if ( defined $row ) {
2360 $row->update($cond);
2364 return $self->new_result($cond);
2371 =item Arguments: none
2373 =item Return Value: \@cache_objects?
2377 Gets the contents of the cache for the resultset, if the cache is set.
2379 The cache is populated either by using the L</prefetch> attribute to
2380 L</search> or by calling L</set_cache>.
2392 =item Arguments: \@cache_objects
2394 =item Return Value: \@cache_objects
2398 Sets the contents of the cache for the resultset. Expects an arrayref
2399 of objects of the same class as those produced by the resultset. Note that
2400 if the cache is set the resultset will return the cached objects rather
2401 than re-querying the database even if the cache attr is not set.
2403 The contents of the cache can also be populated by using the
2404 L</prefetch> attribute to L</search>.
2409 my ( $self, $data ) = @_;
2410 $self->throw_exception("set_cache requires an arrayref")
2411 if defined($data) && (ref $data ne 'ARRAY');
2412 $self->{all_cache} = $data;
2419 =item Arguments: none
2421 =item Return Value: []
2425 Clears the cache for the resultset.
2430 shift->set_cache(undef);
2437 =item Arguments: none
2439 =item Return Value: true, if the resultset has been paginated
2447 return !!$self->{attrs}{page};
2454 =item Arguments: none
2456 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2464 return scalar $self->result_source->storage->_parse_order_by($self->{attrs}{order_by});
2467 =head2 related_resultset
2471 =item Arguments: $relationship_name
2473 =item Return Value: $resultset
2477 Returns a related resultset for the supplied relationship name.
2479 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2483 sub related_resultset {
2484 my ($self, $rel) = @_;
2486 $self->{related_resultsets} ||= {};
2487 return $self->{related_resultsets}{$rel} ||= do {
2488 my $rsrc = $self->result_source;
2489 my $rel_info = $rsrc->relationship_info($rel);
2491 $self->throw_exception(
2492 "search_related: result source '" . $rsrc->source_name .
2493 "' has no such relationship $rel")
2496 my $attrs = $self->_chain_relationship($rel);
2498 my $join_count = $attrs->{seen_join}{$rel};
2500 my $alias = $self->result_source->storage
2501 ->relname_to_table_alias($rel, $join_count);
2503 # since this is search_related, and we already slid the select window inwards
2504 # (the select/as attrs were deleted in the beginning), we need to flip all
2505 # left joins to inner, so we get the expected results
2506 # read the comment on top of the actual function to see what this does
2507 $attrs->{from} = $rsrc->schema->storage->_straight_join_to_node ($attrs->{from}, $alias);
2510 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2511 delete @{$attrs}{qw(result_class alias)};
2515 if (my $cache = $self->get_cache) {
2516 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2517 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
2522 my $rel_source = $rsrc->related_source($rel);
2526 # The reason we do this now instead of passing the alias to the
2527 # search_rs below is that if you wrap/overload resultset on the
2528 # source you need to know what alias it's -going- to have for things
2529 # to work sanely (e.g. RestrictWithObject wants to be able to add
2530 # extra query restrictions, and these may need to be $alias.)
2532 my $rel_attrs = $rel_source->resultset_attributes;
2533 local $rel_attrs->{alias} = $alias;
2535 $rel_source->resultset
2539 where => $attrs->{where},
2542 $new->set_cache($new_cache) if $new_cache;
2547 =head2 current_source_alias
2551 =item Arguments: none
2553 =item Return Value: $source_alias
2557 Returns the current table alias for the result source this resultset is built
2558 on, that will be used in the SQL query. Usually it is C<me>.
2560 Currently the source alias that refers to the result set returned by a
2561 L</search>/L</find> family method depends on how you got to the resultset: it's
2562 C<me> by default, but eg. L</search_related> aliases it to the related result
2563 source name (and keeps C<me> referring to the original result set). The long
2564 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
2565 (and make this method unnecessary).
2567 Thus it's currently necessary to use this method in predefined queries (see
2568 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
2569 source alias of the current result set:
2571 # in a result set class
2573 my ($self, $user) = @_;
2575 my $me = $self->current_source_alias;
2577 return $self->search(
2578 "$me.modified" => $user->id,
2584 sub current_source_alias {
2587 return ($self->{attrs} || {})->{alias} || 'me';
2590 =head2 as_subselect_rs
2594 =item Arguments: none
2596 =item Return Value: $resultset
2600 Act as a barrier to SQL symbols. The resultset provided will be made into a
2601 "virtual view" by including it as a subquery within the from clause. From this
2602 point on, any joined tables are inaccessible to ->search on the resultset (as if
2603 it were simply where-filtered without joins). For example:
2605 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
2607 # 'x' now pollutes the query namespace
2609 # So the following works as expected
2610 my $ok_rs = $rs->search({'x.other' => 1});
2612 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
2613 # def) we look for one row with contradictory terms and join in another table
2614 # (aliased 'x_2') which we never use
2615 my $broken_rs = $rs->search({'x.name' => 'def'});
2617 my $rs2 = $rs->as_subselect_rs;
2619 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
2620 my $not_joined_rs = $rs2->search({'x.other' => 1});
2622 # works as expected: finds a 'table' row related to two x rows (abc and def)
2623 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
2625 Another example of when one might use this would be to select a subset of
2626 columns in a group by clause:
2628 my $rs = $schema->resultset('Bar')->search(undef, {
2629 group_by => [qw{ id foo_id baz_id }],
2630 })->as_subselect_rs->search(undef, {
2631 columns => [qw{ id foo_id }]
2634 In the above example normally columns would have to be equal to the group by,
2635 but because we isolated the group by into a subselect the above works.
2639 sub as_subselect_rs {
2642 return $self->result_source->resultset->search( undef, {
2643 alias => $self->current_source_alias,
2645 $self->current_source_alias => $self->as_query,
2646 -alias => $self->current_source_alias,
2647 -source_handle => $self->result_source->handle,
2652 # This code is called by search_related, and makes sure there
2653 # is clear separation between the joins before, during, and
2654 # after the relationship. This information is needed later
2655 # in order to properly resolve prefetch aliases (any alias
2656 # with a relation_chain_depth less than the depth of the
2657 # current prefetch is not considered)
2659 # The increments happen twice per join. An even number means a
2660 # relationship specified via a search_related, whereas an odd
2661 # number indicates a join/prefetch added via attributes
2663 # Also this code will wrap the current resultset (the one we
2664 # chain to) in a subselect IFF it contains limiting attributes
2665 sub _chain_relationship {
2666 my ($self, $rel) = @_;
2667 my $source = $self->result_source;
2668 my $attrs = { %{$self->{attrs}||{}} };
2670 # we need to take the prefetch the attrs into account before we
2671 # ->_resolve_join as otherwise they get lost - captainL
2672 my $join = $self->_merge_attr( $attrs->{join}, $attrs->{prefetch} );
2674 delete @{$attrs}{qw/join prefetch collapse distinct select as columns +select +as +columns/};
2676 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
2679 my @force_subq_attrs = qw/offset rows group_by having/;
2682 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
2684 $self->_has_resolved_attr (@force_subq_attrs)
2686 # Nuke the prefetch (if any) before the new $rs attrs
2687 # are resolved (prefetch is useless - we are wrapping
2688 # a subquery anyway).
2689 my $rs_copy = $self->search;
2690 $rs_copy->{attrs}{join} = $self->_merge_attr (
2691 $rs_copy->{attrs}{join},
2692 delete $rs_copy->{attrs}{prefetch},
2696 -source_handle => $source->handle,
2697 -alias => $attrs->{alias},
2698 $attrs->{alias} => $rs_copy->as_query,
2700 delete @{$attrs}{@force_subq_attrs, 'where'};
2701 $seen->{-relation_chain_depth} = 0;
2703 elsif ($attrs->{from}) { #shallow copy suffices
2704 $from = [ @{$attrs->{from}} ];
2708 -source_handle => $source->handle,
2709 -alias => $attrs->{alias},
2710 $attrs->{alias} => $source->from,
2714 my $jpath = ($seen->{-relation_chain_depth})
2715 ? $from->[-1][0]{-join_path}
2718 my @requested_joins = $source->_resolve_join(
2725 push @$from, @requested_joins;
2727 $seen->{-relation_chain_depth}++;
2729 # if $self already had a join/prefetch specified on it, the requested
2730 # $rel might very well be already included. What we do in this case
2731 # is effectively a no-op (except that we bump up the chain_depth on
2732 # the join in question so we could tell it *is* the search_related)
2735 # we consider the last one thus reverse
2736 for my $j (reverse @requested_joins) {
2737 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
2738 if ($rel eq $last_j) {
2739 $j->[0]{-relation_chain_depth}++;
2745 unless ($already_joined) {
2746 push @$from, $source->_resolve_join(
2754 $seen->{-relation_chain_depth}++;
2756 return {%$attrs, from => $from, seen_join => $seen};
2759 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
2760 sub _resolved_attrs_copy {
2762 return { %{$self->_resolved_attrs (@_)} };
2765 sub _resolved_attrs {
2767 return $self->{_attrs} if $self->{_attrs};
2769 my $attrs = { %{ $self->{attrs} || {} } };
2770 my $source = $self->result_source;
2771 my $alias = $attrs->{alias};
2773 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
2776 # build columns (as long as select isn't set) into a set of as/select hashes
2777 unless ( $attrs->{select} ) {
2780 if ( ref $attrs->{columns} eq 'ARRAY' ) {
2781 @cols = @{ delete $attrs->{columns}}
2782 } elsif ( defined $attrs->{columns} ) {
2783 @cols = delete $attrs->{columns}
2785 @cols = $source->columns
2789 if ( ref $_ eq 'HASH' ) {
2792 my $key = /^\Q${alias}.\E(.+)$/
2798 push @colbits, { $key => $value };
2803 # add the additional columns on
2804 foreach (qw{include_columns +columns}) {
2805 if ( $attrs->{$_} ) {
2806 my @list = ( ref($attrs->{$_}) eq 'ARRAY' )
2807 ? @{ delete $attrs->{$_} }
2808 : delete $attrs->{$_};
2810 if ( ref($_) eq 'HASH' ) {
2813 my $key = ( split /\./, $_ )[-1];
2814 my $value = ( /\./ ? $_ : "$alias.$_" );
2815 push @colbits, { $key => $value };
2821 # start with initial select items
2822 if ( $attrs->{select} ) {
2824 ( ref $attrs->{select} eq 'ARRAY' )
2825 ? [ @{ $attrs->{select} } ]
2826 : [ $attrs->{select} ];
2828 if ( $attrs->{as} ) {
2831 ref $attrs->{as} eq 'ARRAY'
2832 ? [ @{ $attrs->{as} } ]
2836 $attrs->{as} = [ map {
2837 m/^\Q${alias}.\E(.+)$/
2840 } @{ $attrs->{select} }
2845 # otherwise we intialise select & as to empty
2846 $attrs->{select} = [];
2850 # now add colbits to select/as
2851 push @{ $attrs->{select} }, map values %{$_}, @colbits;
2852 push @{ $attrs->{as} }, map keys %{$_}, @colbits;
2854 if ( my $adds = delete $attrs->{'+select'} ) {
2855 $adds = [$adds] unless ref $adds eq 'ARRAY';
2856 push @{ $attrs->{select} },
2857 map { /\./ || ref $_ ? $_ : "$alias.$_" } @$adds;
2859 if ( my $adds = delete $attrs->{'+as'} ) {
2860 $adds = [$adds] unless ref $adds eq 'ARRAY';
2861 push @{ $attrs->{as} }, @$adds;
2864 $attrs->{from} ||= [{
2865 -source_handle => $source->handle,
2866 -alias => $self->{attrs}{alias},
2867 $self->{attrs}{alias} => $source->from,
2870 if ( $attrs->{join} || $attrs->{prefetch} ) {
2872 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
2873 if ref $attrs->{from} ne 'ARRAY';
2875 my $join = delete $attrs->{join} || {};
2877 if ( defined $attrs->{prefetch} ) {
2878 $join = $self->_merge_attr( $join, $attrs->{prefetch} );
2881 $attrs->{from} = # have to copy here to avoid corrupting the original
2883 @{ $attrs->{from} },
2884 $source->_resolve_join(
2887 { %{ $attrs->{seen_join} || {} } },
2888 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
2889 ? $attrs->{from}[-1][0]{-join_path}
2896 if ( defined $attrs->{order_by} ) {
2897 $attrs->{order_by} = (
2898 ref( $attrs->{order_by} ) eq 'ARRAY'
2899 ? [ @{ $attrs->{order_by} } ]
2900 : [ $attrs->{order_by} || () ]
2904 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
2905 $attrs->{group_by} = [ $attrs->{group_by} ];
2908 # generate the distinct induced group_by early, as prefetch will be carried via a
2909 # subquery (since a group_by is present)
2910 if (delete $attrs->{distinct}) {
2911 if ($attrs->{group_by}) {
2912 carp ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
2915 $attrs->{group_by} = [ grep { !ref($_) || (ref($_) ne 'HASH') } @{$attrs->{select}} ];
2917 # add any order_by parts that are not already present in the group_by
2918 # we need to be careful not to add any named functions/aggregates
2919 # i.e. select => [ ... { count => 'foo', -as 'foocount' } ... ]
2920 my %already_grouped = map { $_ => 1 } (@{$attrs->{group_by}});
2922 my $storage = $self->result_source->schema->storage;
2924 my $rs_column_list = $storage->_resolve_column_info ($attrs->{from});
2926 for my $chunk ($storage->_parse_order_by($attrs->{order_by})) {
2927 if ($rs_column_list->{$chunk} && not $already_grouped{$chunk}++) {
2928 push @{$attrs->{group_by}}, $chunk;
2934 if ( my $prefetch = delete $attrs->{prefetch} ) {
2935 $attrs->{collapse} = 1;
2937 my $prefetch_ordering = [];
2939 # this is a separate structure (we don't look in {from} directly)
2940 # as the resolver needs to shift things off the lists to work
2941 # properly (identical-prefetches on different branches)
2943 if (ref $attrs->{from} eq 'ARRAY') {
2945 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
2947 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
2948 next unless $j->[0]{-alias};
2949 next unless $j->[0]{-join_path};
2950 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
2952 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
2955 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
2956 push @{$p->{-join_aliases} }, $j->[0]{-alias};
2960 my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering );
2962 # we need to somehow mark which columns came from prefetch
2963 $attrs->{_prefetch_select} = [ map { $_->[0] } @prefetch ];
2965 push @{ $attrs->{select} }, @{$attrs->{_prefetch_select}};
2966 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
2968 push( @{$attrs->{order_by}}, @$prefetch_ordering );
2969 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
2972 # run through the resulting joinstructure (starting from our current slot)
2973 # and unset collapse if proven unnesessary
2974 if ($attrs->{collapse} && ref $attrs->{from} eq 'ARRAY') {
2976 if (@{$attrs->{from}} > 1) {
2978 # find where our table-spec starts and consider only things after us
2979 my @fromlist = @{$attrs->{from}};
2981 my $t = shift @fromlist;
2982 $t = $t->[0] if ref $t eq 'ARRAY'; #me vs join from-spec mismatch
2983 last if ($t->{-alias} && $t->{-alias} eq $alias);
2987 $attrs->{collapse} = scalar grep { ! $_->[0]{-is_single} } (@fromlist);
2991 # no joins - no collapse
2992 $attrs->{collapse} = 0;
2996 # if both page and offset are specified, produce a combined offset
2997 # even though it doesn't make much sense, this is what pre 081xx has
2999 if (my $page = delete $attrs->{page}) {
3001 ($attrs->{rows} * ($page - 1))
3003 ($attrs->{offset} || 0)
3007 return $self->{_attrs} = $attrs;
3011 my ($self, $attr) = @_;
3013 if (ref $attr eq 'HASH') {
3014 return $self->_rollout_hash($attr);
3015 } elsif (ref $attr eq 'ARRAY') {
3016 return $self->_rollout_array($attr);
3022 sub _rollout_array {
3023 my ($self, $attr) = @_;
3026 foreach my $element (@{$attr}) {
3027 if (ref $element eq 'HASH') {
3028 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3029 } elsif (ref $element eq 'ARRAY') {
3030 # XXX - should probably recurse here
3031 push( @rolled_array, @{$self->_rollout_array($element)} );
3033 push( @rolled_array, $element );
3036 return \@rolled_array;
3040 my ($self, $attr) = @_;
3043 foreach my $key (keys %{$attr}) {
3044 push( @rolled_array, { $key => $attr->{$key} } );
3046 return \@rolled_array;
3049 sub _calculate_score {
3050 my ($self, $a, $b) = @_;
3052 if (defined $a xor defined $b) {
3055 elsif (not defined $a) {
3059 if (ref $b eq 'HASH') {
3060 my ($b_key) = keys %{$b};
3061 if (ref $a eq 'HASH') {
3062 my ($a_key) = keys %{$a};
3063 if ($a_key eq $b_key) {
3064 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3069 return ($a eq $b_key) ? 1 : 0;
3072 if (ref $a eq 'HASH') {
3073 my ($a_key) = keys %{$a};
3074 return ($b eq $a_key) ? 1 : 0;
3076 return ($b eq $a) ? 1 : 0;
3082 my ($self, $orig, $import) = @_;
3084 return $import unless defined($orig);
3085 return $orig unless defined($import);
3087 $orig = $self->_rollout_attr($orig);
3088 $import = $self->_rollout_attr($import);
3091 foreach my $import_element ( @{$import} ) {
3092 # find best candidate from $orig to merge $b_element into
3093 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3094 foreach my $orig_element ( @{$orig} ) {
3095 my $score = $self->_calculate_score( $orig_element, $import_element );
3096 if ($score > $best_candidate->{score}) {
3097 $best_candidate->{position} = $position;
3098 $best_candidate->{score} = $score;
3102 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3104 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3105 push( @{$orig}, $import_element );
3107 my $orig_best = $orig->[$best_candidate->{position}];
3108 # merge orig_best and b_element together and replace original with merged
3109 if (ref $orig_best ne 'HASH') {
3110 $orig->[$best_candidate->{position}] = $import_element;
3111 } elsif (ref $import_element eq 'HASH') {
3112 my ($key) = keys %{$orig_best};
3113 $orig->[$best_candidate->{position}] = { $key => $self->_merge_attr($orig_best->{$key}, $import_element->{$key}) };
3116 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3126 $self->_source_handle($_[0]->handle);
3128 $self->_source_handle->resolve;
3132 =head2 throw_exception
3134 See L<DBIx::Class::Schema/throw_exception> for details.
3138 sub throw_exception {
3141 if (ref $self && $self->_source_handle->schema) {
3142 $self->_source_handle->schema->throw_exception(@_)
3145 DBIx::Class::Exception->throw(@_);
3149 # XXX: FIXME: Attributes docs need clearing up
3153 Attributes are used to refine a ResultSet in various ways when
3154 searching for data. They can be passed to any method which takes an
3155 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3158 These are in no particular order:
3164 =item Value: ( $order_by | \@order_by | \%order_by )
3168 Which column(s) to order the results by.
3170 [The full list of suitable values is documented in
3171 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3174 If a single column name, or an arrayref of names is supplied, the
3175 argument is passed through directly to SQL. The hashref syntax allows
3176 for connection-agnostic specification of ordering direction:
3178 For descending order:
3180 order_by => { -desc => [qw/col1 col2 col3/] }
3182 For explicit ascending order:
3184 order_by => { -asc => 'col' }
3186 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3187 supported, although you are strongly encouraged to use the hashref
3188 syntax as outlined above.
3194 =item Value: \@columns
3198 Shortcut to request a particular set of columns to be retrieved. Each
3199 column spec may be a string (a table column name), or a hash (in which
3200 case the key is the C<as> value, and the value is used as the C<select>
3201 expression). Adds C<me.> onto the start of any column without a C<.> in
3202 it and sets C<select> from that, then auto-populates C<as> from
3203 C<select> as normal. (You may also use the C<cols> attribute, as in
3204 earlier versions of DBIC.)
3210 =item Value: \@columns
3214 Indicates additional columns to be selected from storage. Works the same
3215 as L</columns> but adds columns to the selection. (You may also use the
3216 C<include_columns> attribute, as in earlier versions of DBIC). For
3219 $schema->resultset('CD')->search(undef, {
3220 '+columns' => ['artist.name'],
3224 would return all CDs and include a 'name' column to the information
3225 passed to object inflation. Note that the 'artist' is the name of the
3226 column (or relationship) accessor, and 'name' is the name of the column
3227 accessor in the related table.
3229 =head2 include_columns
3233 =item Value: \@columns
3237 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3243 =item Value: \@select_columns
3247 Indicates which columns should be selected from the storage. You can use
3248 column names, or in the case of RDBMS back ends, function or stored procedure
3251 $rs = $schema->resultset('Employee')->search(undef, {
3254 { count => 'employeeid' },
3259 When you use function/stored procedure names and do not supply an C<as>
3260 attribute, the column names returned are storage-dependent. E.g. MySQL would
3261 return a column named C<count(employeeid)> in the above example.
3263 B<NOTE:> You will almost always need a corresponding 'as' entry when you use
3270 Indicates additional columns to be selected from storage. Works the same as
3271 L</select> but adds columns to the selection.
3279 Indicates additional column names for those added via L</+select>. See L</as>.
3287 =item Value: \@inflation_names
3291 Indicates column names for object inflation. That is, C<as>
3292 indicates the name that the column can be accessed as via the
3293 C<get_column> method (or via the object accessor, B<if one already
3294 exists>). It has nothing to do with the SQL code C<SELECT foo AS bar>.
3296 The C<as> attribute is used in conjunction with C<select>,
3297 usually when C<select> contains one or more function or stored
3300 $rs = $schema->resultset('Employee')->search(undef, {
3303 { count => 'employeeid' }
3305 as => ['name', 'employee_count'],
3308 my $employee = $rs->first(); # get the first Employee
3310 If the object against which the search is performed already has an accessor
3311 matching a column name specified in C<as>, the value can be retrieved using
3312 the accessor as normal:
3314 my $name = $employee->name();
3316 If on the other hand an accessor does not exist in the object, you need to
3317 use C<get_column> instead:
3319 my $employee_count = $employee->get_column('employee_count');
3321 You can create your own accessors if required - see
3322 L<DBIx::Class::Manual::Cookbook> for details.
3324 Please note: This will NOT insert an C<AS employee_count> into the SQL
3325 statement produced, it is used for internal access only. Thus
3326 attempting to use the accessor in an C<order_by> clause or similar
3327 will fail miserably.
3329 To get around this limitation, you can supply literal SQL to your
3330 C<select> attribute that contains the C<AS alias> text, e.g.
3332 select => [\'myfield AS alias']
3338 =item Value: ($rel_name | \@rel_names | \%rel_names)
3342 Contains a list of relationships that should be joined for this query. For
3345 # Get CDs by Nine Inch Nails
3346 my $rs = $schema->resultset('CD')->search(
3347 { 'artist.name' => 'Nine Inch Nails' },
3348 { join => 'artist' }
3351 Can also contain a hash reference to refer to the other relation's relations.
3354 package MyApp::Schema::Track;
3355 use base qw/DBIx::Class/;
3356 __PACKAGE__->table('track');
3357 __PACKAGE__->add_columns(qw/trackid cd position title/);
3358 __PACKAGE__->set_primary_key('trackid');
3359 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3362 # In your application
3363 my $rs = $schema->resultset('Artist')->search(
3364 { 'track.title' => 'Teardrop' },
3366 join => { cd => 'track' },
3367 order_by => 'artist.name',
3371 You need to use the relationship (not the table) name in conditions,
3372 because they are aliased as such. The current table is aliased as "me", so
3373 you need to use me.column_name in order to avoid ambiguity. For example:
3375 # Get CDs from 1984 with a 'Foo' track
3376 my $rs = $schema->resultset('CD')->search(
3379 'tracks.name' => 'Foo'
3381 { join => 'tracks' }
3384 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3385 similarly for a third time). For e.g.
3387 my $rs = $schema->resultset('Artist')->search({
3388 'cds.title' => 'Down to Earth',
3389 'cds_2.title' => 'Popular',
3391 join => [ qw/cds cds/ ],
3394 will return a set of all artists that have both a cd with title 'Down
3395 to Earth' and a cd with title 'Popular'.
3397 If you want to fetch related objects from other tables as well, see C<prefetch>
3400 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3406 =item Value: ($rel_name | \@rel_names | \%rel_names)
3410 Contains one or more relationships that should be fetched along with
3411 the main query (when they are accessed afterwards the data will
3412 already be available, without extra queries to the database). This is
3413 useful for when you know you will need the related objects, because it
3414 saves at least one query:
3416 my $rs = $schema->resultset('Tag')->search(
3425 The initial search results in SQL like the following:
3427 SELECT tag.*, cd.*, artist.* FROM tag
3428 JOIN cd ON tag.cd = cd.cdid
3429 JOIN artist ON cd.artist = artist.artistid
3431 L<DBIx::Class> has no need to go back to the database when we access the
3432 C<cd> or C<artist> relationships, which saves us two SQL statements in this
3435 Simple prefetches will be joined automatically, so there is no need
3436 for a C<join> attribute in the above search.
3438 C<prefetch> can be used with the following relationship types: C<belongs_to>,
3439 C<has_one> (or if you're using C<add_relationship>, any relationship declared
3440 with an accessor type of 'single' or 'filter'). A more complex example that
3441 prefetches an artists cds, the tracks on those cds, and the tags associated
3442 with that artist is given below (assuming many-to-many from artists to tags):
3444 my $rs = $schema->resultset('Artist')->search(
3448 { cds => 'tracks' },
3449 { artist_tags => 'tags' }
3455 B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
3456 attributes will be ignored.
3458 B<CAVEATs>: Prefetch does a lot of deep magic. As such, it may not behave
3459 exactly as you might expect.
3465 Prefetch uses the L</cache> to populate the prefetched relationships. This
3466 may or may not be what you want.
3470 If you specify a condition on a prefetched relationship, ONLY those
3471 rows that match the prefetched condition will be fetched into that relationship.
3472 This means that adding prefetch to a search() B<may alter> what is returned by
3473 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
3475 my $artist_rs = $schema->resultset('Artist')->search({
3481 my $count = $artist_rs->first->cds->count;
3483 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
3485 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
3487 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
3489 that cmp_ok() may or may not pass depending on the datasets involved. This
3490 behavior may or may not survive the 0.09 transition.
3502 Makes the resultset paged and specifies the page to retrieve. Effectively
3503 identical to creating a non-pages resultset and then calling ->page($page)
3506 If L<rows> attribute is not specified it defaults to 10 rows per page.
3508 When you have a paged resultset, L</count> will only return the number
3509 of rows in the page. To get the total, use the L</pager> and call
3510 C<total_entries> on it.
3520 Specifies the maximum number of rows for direct retrieval or the number of
3521 rows per page if the page attribute or method is used.
3527 =item Value: $offset
3531 Specifies the (zero-based) row number for the first row to be returned, or the
3532 of the first row of the first page if paging is used.
3538 =item Value: \@columns
3542 A arrayref of columns to group by. Can include columns of joined tables.
3544 group_by => [qw/ column1 column2 ... /]
3550 =item Value: $condition
3554 HAVING is a select statement attribute that is applied between GROUP BY and
3555 ORDER BY. It is applied to the after the grouping calculations have been
3558 having => { 'count(employee)' => { '>=', 100 } }
3564 =item Value: (0 | 1)
3568 Set to 1 to group by all columns. If the resultset already has a group_by
3569 attribute, this setting is ignored and an appropriate warning is issued.
3575 Adds to the WHERE clause.
3577 # only return rows WHERE deleted IS NULL for all searches
3578 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
3580 Can be overridden by passing C<< { where => undef } >> as an attribute
3587 Set to 1 to cache search results. This prevents extra SQL queries if you
3588 revisit rows in your ResultSet:
3590 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
3592 while( my $artist = $resultset->next ) {
3596 $rs->first; # without cache, this would issue a query
3598 By default, searches are not cached.
3600 For more examples of using these attributes, see
3601 L<DBIx::Class::Manual::Cookbook>.
3607 =item Value: ( 'update' | 'shared' )
3611 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT