1 package DBIx::Class::ResultSet;
9 use Carp::Clan qw/^DBIx::Class/;
10 use DBIx::Class::Exception;
13 use DBIx::Class::ResultSetColumn;
14 use DBIx::Class::ResultSourceHandle;
17 use base qw/DBIx::Class/;
19 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class _source_handle/);
23 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
27 my $users_rs = $schema->resultset('User');
28 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
29 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
33 A ResultSet is an object which stores a set of conditions representing
34 a query. It is the backbone of DBIx::Class (i.e. the really
35 important/useful bit).
37 No SQL is executed on the database when a ResultSet is created, it
38 just stores all the conditions needed to create the query.
40 A basic ResultSet representing the data of an entire table is returned
41 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
42 L<Source|DBIx::Class::Manual::Glossary/Source> name.
44 my $users_rs = $schema->resultset('User');
46 A new ResultSet is returned from calling L</search> on an existing
47 ResultSet. The new one will contain all the conditions of the
48 original, plus any new conditions added in the C<search> call.
50 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
51 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
54 The query that the ResultSet represents is B<only> executed against
55 the database when these methods are called:
56 L</find> L</next> L</all> L</first> L</single> L</count>
60 =head2 Chaining resultsets
62 Let's say you've got a query that needs to be run to return some data
63 to the user. But, you have an authorization system in place that
64 prevents certain users from seeing certain information. So, you want
65 to construct the basic query in one method, but add constraints to it in
70 my $request = $self->get_request; # Get a request object somehow.
71 my $schema = $self->get_schema; # Get the DBIC schema object somehow.
73 my $cd_rs = $schema->resultset('CD')->search({
74 title => $request->param('title'),
75 year => $request->param('year'),
78 $self->apply_security_policy( $cd_rs );
83 sub apply_security_policy {
92 =head3 Resolving conditions and attributes
94 When a resultset is chained from another resultset, conditions and
95 attributes with the same keys need resolving.
97 L</join>, L</prefetch>, L</+select>, L</+as> attributes are merged
98 into the existing ones from the original resultset.
100 The L</where>, L</having> attribute, and any search conditions are
101 merged with an SQL C<AND> to the existing condition from the original
104 All other attributes are overridden by any new ones supplied in the
107 =head2 Multiple queries
109 Since a resultset just defines a query, you can do all sorts of
110 things with it with the same object.
112 # Don't hit the DB yet.
113 my $cd_rs = $schema->resultset('CD')->search({
114 title => 'something',
118 # Each of these hits the DB individually.
119 my $count = $cd_rs->count;
120 my $most_recent = $cd_rs->get_column('date_released')->max();
121 my @records = $cd_rs->all;
123 And it's not just limited to SELECT statements.
129 $cd_rs->create({ artist => 'Fred' });
131 Which is the same as:
133 $schema->resultset('CD')->create({
134 title => 'something',
139 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
143 If a resultset is used in a numeric context it returns the L</count>.
144 However, if it is used in a booleand context it is always true. So if
145 you want to check if a resultset has any results use C<if $rs != 0>.
146 C<if $rs> will always be true.
154 =item Arguments: $source, \%$attrs
156 =item Return Value: $rs
160 The resultset constructor. Takes a source object (usually a
161 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
162 L</ATTRIBUTES> below). Does not perform any queries -- these are
163 executed as needed by the other methods.
165 Generally you won't need to construct a resultset manually. You'll
166 automatically get one from e.g. a L</search> called in scalar context:
168 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
170 IMPORTANT: If called on an object, proxies to new_result instead so
172 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
174 will return a CD object, not a ResultSet.
180 return $class->new_result(@_) if ref $class;
182 my ($source, $attrs) = @_;
183 $source = $source->handle
184 unless $source->isa('DBIx::Class::ResultSourceHandle');
185 $attrs = { %{$attrs||{}} };
187 if ($attrs->{page}) {
188 $attrs->{rows} ||= 10;
191 $attrs->{alias} ||= 'me';
193 # Creation of {} and bless separated to mitigate RH perl bug
194 # see https://bugzilla.redhat.com/show_bug.cgi?id=196836
196 _source_handle => $source,
197 cond => $attrs->{where},
206 $attrs->{result_class} || $source->resolve->result_class
216 =item Arguments: $cond, \%attrs?
218 =item Return Value: $resultset (scalar context), @row_objs (list context)
222 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
223 my $new_rs = $cd_rs->search({ year => 2005 });
225 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
226 # year = 2005 OR year = 2004
228 If you need to pass in additional attributes but no additional condition,
229 call it as C<search(undef, \%attrs)>.
231 # "SELECT name, artistid FROM $artist_table"
232 my @all_artists = $schema->resultset('Artist')->search(undef, {
233 columns => [qw/name artistid/],
236 For a list of attributes that can be passed to C<search>, see
237 L</ATTRIBUTES>. For more examples of using this function, see
238 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
239 documentation for the first argument, see L<SQL::Abstract>.
241 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
247 my $rs = $self->search_rs( @_ );
248 return (wantarray ? $rs->all : $rs);
255 =item Arguments: $cond, \%attrs?
257 =item Return Value: $resultset
261 This method does the same exact thing as search() except it will
262 always return a resultset, even in list context.
269 # Special-case handling for (undef, undef).
270 if ( @_ == 2 && !defined $_[1] && !defined $_[0] ) {
275 $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
276 my $our_attrs = { %{$self->{attrs}} };
277 my $having = delete $our_attrs->{having};
278 my $where = delete $our_attrs->{where};
282 my %safe = (alias => 1, cache => 1);
285 (@_ && defined($_[0])) # @_ == () or (undef)
287 (keys %$attrs # empty attrs or only 'safe' attrs
288 && List::Util::first { !$safe{$_} } keys %$attrs)
290 # no search, effectively just a clone
291 $rows = $self->get_cache;
294 # 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 databse 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 (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 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 restultset, 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 = $schema->resultset('CD')->single({ year => 2001 });
687 Inflates the first result without creating a cursor if the resultset has
688 any records in it; if not returns nothing. Used by L</find> as a lean version of
691 While this method can take an optional search condition (just like L</search>)
692 being a fast-code-path it does not recognize search attributes. If you need to
693 add extra joins or similar, call L</search> and then chain-call L</single> on the
694 L<DBIx::Class::ResultSet> returned.
700 As of 0.08100, this method enforces the assumption that the preceeding
701 query returns only one row. If more than one row is returned, you will receive
704 Query returned more than one row
706 In this case, you should be using L</next> or L</find> instead, or if you really
707 know what you are doing, use the L</rows> attribute to explicitly limit the size
710 This method will also throw an exception if it is called on a resultset prefetching
711 has_many, as such a prefetch implies fetching multiple rows from the database in
712 order to assemble the resulting object.
719 my ($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} = $where;
744 # XXX: Disabled since it doesn't infer uniqueness in all cases
745 # unless ($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 = keys %{ $self->{_attrs}{collapse} || {} };
1006 my @row = @$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);
1116 $self->_result_class;
1123 =item Arguments: $cond, \%attrs??
1125 =item Return Value: $count
1129 Performs an SQL C<COUNT> with the same query as the resultset was built
1130 with to find the number of elements. Passing arguments is equivalent to
1131 C<< $rs->search ($cond, \%attrs)->count >>
1137 return $self->search(@_)->count if @_ and defined $_[0];
1138 return scalar @{ $self->get_cache } if $self->get_cache;
1140 my $attrs = $self->_resolved_attrs_copy;
1142 # this is a little optimization - it is faster to do the limit
1143 # adjustments in software, instead of a subquery
1144 my $rows = delete $attrs->{rows};
1145 my $offset = delete $attrs->{offset};
1148 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1149 $crs = $self->_count_subq_rs ($attrs);
1152 $crs = $self->_count_rs ($attrs);
1154 my $count = $crs->next;
1156 $count -= $offset if $offset;
1157 $count = $rows if $rows and $rows < $count;
1158 $count = 0 if ($count < 0);
1167 =item Arguments: $cond, \%attrs??
1169 =item Return Value: $count_rs
1173 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1174 This can be very handy for subqueries:
1176 ->search( { amount => $some_rs->count_rs->as_query } )
1178 As with regular resultsets the SQL query will be executed only after
1179 the resultset is accessed via L</next> or L</all>. That would return
1180 the same single value obtainable via L</count>.
1186 return $self->search(@_)->count_rs if @_;
1188 # this may look like a lack of abstraction (count() does about the same)
1189 # but in fact an _rs *must* use a subquery for the limits, as the
1190 # software based limiting can not be ported if this $rs is to be used
1191 # in a subquery itself (i.e. ->as_query)
1192 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1193 return $self->_count_subq_rs;
1196 return $self->_count_rs;
1201 # returns a ResultSetColumn object tied to the count query
1204 my ($self, $attrs) = @_;
1206 my $rsrc = $self->result_source;
1207 $attrs ||= $self->_resolved_attrs;
1209 my $tmp_attrs = { %$attrs };
1211 # take off any limits, record_filter is cdbi, and no point of ordering a count
1212 delete $tmp_attrs->{$_} for (qw/select as rows offset order_by record_filter/);
1214 # overwrite the selector (supplied by the storage)
1215 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $tmp_attrs);
1216 $tmp_attrs->{as} = 'count';
1218 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1224 # same as above but uses a subquery
1226 sub _count_subq_rs {
1227 my ($self, $attrs) = @_;
1229 my $rsrc = $self->result_source;
1230 $attrs ||= $self->_resolved_attrs_copy;
1232 my $sub_attrs = { %$attrs };
1234 # extra selectors do not go in the subquery and there is no point of ordering it
1235 delete $sub_attrs->{$_} for qw/collapse select _prefetch_select as order_by/;
1237 # if we multi-prefetch we group_by primary keys only as this is what we would
1238 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1239 if ( keys %{$attrs->{collapse}} ) {
1240 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } ($rsrc->primary_columns) ]
1243 $sub_attrs->{select} = $rsrc->storage->_subq_count_select ($rsrc, $sub_attrs);
1245 # this is so that the query can be simplified e.g.
1246 # * ordering can be thrown away in things like Top limit
1247 $sub_attrs->{-for_count_only} = 1;
1249 my $sub_rs = $rsrc->resultset_class->new ($rsrc, $sub_attrs);
1252 -alias => 'count_subq',
1253 -source_handle => $rsrc->handle,
1254 count_subq => $sub_rs->as_query,
1257 # the subquery replaces this
1258 delete $attrs->{$_} for qw/where bind collapse group_by having having_bind rows offset/;
1260 return $self->_count_rs ($attrs);
1267 =head2 count_literal
1271 =item Arguments: $sql_fragment, @bind_values
1273 =item Return Value: $count
1277 Counts the results in a literal query. Equivalent to calling L</search_literal>
1278 with the passed arguments, then L</count>.
1282 sub count_literal { shift->search_literal(@_)->count; }
1288 =item Arguments: none
1290 =item Return Value: @objects
1294 Returns all elements in the resultset. Called implicitly if the resultset
1295 is returned in list context.
1302 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1305 return @{ $self->get_cache } if $self->get_cache;
1309 if (keys %{$self->_resolved_attrs->{collapse}}) {
1310 # Using $self->cursor->all is really just an optimisation.
1311 # If we're collapsing has_many prefetches it probably makes
1312 # very little difference, and this is cleaner than hacking
1313 # _construct_object to survive the approach
1314 $self->cursor->reset;
1315 my @row = $self->cursor->next;
1317 push(@obj, $self->_construct_object(@row));
1318 @row = (exists $self->{stashed_row}
1319 ? @{delete $self->{stashed_row}}
1320 : $self->cursor->next);
1323 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1326 $self->set_cache(\@obj) if $self->{attrs}{cache};
1335 =item Arguments: none
1337 =item Return Value: $self
1341 Resets the resultset's cursor, so you can iterate through the elements again.
1342 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1349 delete $self->{_attrs} if exists $self->{_attrs};
1350 $self->{all_cache_position} = 0;
1351 $self->cursor->reset;
1359 =item Arguments: none
1361 =item Return Value: $object?
1365 Resets the resultset and returns an object for the first result (if the
1366 resultset returns anything).
1371 return $_[0]->reset->next;
1377 # Determines whether and what type of subquery is required for the $rs operation.
1378 # If grouping is necessary either supplies its own, or verifies the current one
1379 # After all is done delegates to the proper storage method.
1381 sub _rs_update_delete {
1382 my ($self, $op, $values) = @_;
1384 my $rsrc = $self->result_source;
1386 # if a condition exists we need to strip all table qualifiers
1387 # if this is not possible we'll force a subquery below
1388 my $cond = $rsrc->schema->storage->_strip_cond_qualifiers ($self->{cond});
1390 my $needs_group_by_subq = $self->_has_resolved_attr (qw/collapse group_by -join/);
1391 my $needs_subq = $needs_group_by_subq || (not defined $cond) || $self->_has_resolved_attr(qw/row offset/);
1393 if ($needs_group_by_subq or $needs_subq) {
1395 # make a new $rs selecting only the PKs (that's all we really need)
1396 my $attrs = $self->_resolved_attrs_copy;
1398 delete $attrs->{$_} for qw/collapse select as/;
1399 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->primary_columns) ];
1401 if ($needs_group_by_subq) {
1402 # make sure no group_by was supplied, or if there is one - make sure it matches
1403 # the columns compiled above perfectly. Anything else can not be sanely executed
1404 # on most databases so croak right then and there
1406 if (my $g = $attrs->{group_by}) {
1407 my @current_group_by = map
1408 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1413 join ("\x00", sort @current_group_by)
1415 join ("\x00", sort @{$attrs->{columns}} )
1417 $self->throw_exception (
1418 "You have just attempted a $op operation on a resultset which does group_by"
1419 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1420 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1421 . ' kind of queries. Please retry the operation with a modified group_by or'
1422 . ' without using one at all.'
1427 $attrs->{group_by} = $attrs->{columns};
1431 my $subrs = (ref $self)->new($rsrc, $attrs);
1433 return $self->result_source->storage->_subq_update_delete($subrs, $op, $values);
1436 return $rsrc->storage->$op(
1438 $op eq 'update' ? $values : (),
1448 =item Arguments: \%values
1450 =item Return Value: $storage_rv
1454 Sets the specified columns in the resultset to the supplied values in a
1455 single query. Return value will be true if the update succeeded or false
1456 if no records were updated; exact type of success value is storage-dependent.
1461 my ($self, $values) = @_;
1462 $self->throw_exception('Values for update must be a hash')
1463 unless ref $values eq 'HASH';
1465 return $self->_rs_update_delete ('update', $values);
1472 =item Arguments: \%values
1474 =item Return Value: 1
1478 Fetches all objects and updates them one at a time. Note that C<update_all>
1479 will run DBIC cascade triggers, while L</update> will not.
1484 my ($self, $values) = @_;
1485 $self->throw_exception('Values for update_all must be a hash')
1486 unless ref $values eq 'HASH';
1487 foreach my $obj ($self->all) {
1488 $obj->set_columns($values)->update;
1497 =item Arguments: none
1499 =item Return Value: $storage_rv
1503 Deletes the contents of the resultset from its result source. Note that this
1504 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1505 to run. See also L<DBIx::Class::Row/delete>.
1507 Return value will be the amount of rows deleted; exact type of return value
1508 is storage-dependent.
1514 $self->throw_exception('delete does not accept any arguments')
1517 return $self->_rs_update_delete ('delete');
1524 =item Arguments: none
1526 =item Return Value: 1
1530 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1531 will run DBIC cascade triggers, while L</delete> will not.
1537 $self->throw_exception('delete_all does not accept any arguments')
1540 $_->delete for $self->all;
1548 =item Arguments: \@data;
1552 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1553 For the arrayref of hashrefs style each hashref should be a structure suitable
1554 forsubmitting to a $resultset->create(...) method.
1556 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1557 to insert the data, as this is a faster method.
1559 Otherwise, each set of data is inserted into the database using
1560 L<DBIx::Class::ResultSet/create>, and the resulting objects are
1561 accumulated into an array. The array itself, or an array reference
1562 is returned depending on scalar or list context.
1564 Example: Assuming an Artist Class that has many CDs Classes relating:
1566 my $Artist_rs = $schema->resultset("Artist");
1568 ## Void Context Example
1569 $Artist_rs->populate([
1570 { artistid => 4, name => 'Manufactured Crap', cds => [
1571 { title => 'My First CD', year => 2006 },
1572 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1575 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1576 { title => 'My parents sold me to a record company' ,year => 2005 },
1577 { title => 'Why Am I So Ugly?', year => 2006 },
1578 { title => 'I Got Surgery and am now Popular', year => 2007 }
1583 ## Array Context Example
1584 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1585 { name => "Artist One"},
1586 { name => "Artist Two"},
1587 { name => "Artist Three", cds=> [
1588 { title => "First CD", year => 2007},
1589 { title => "Second CD", year => 2008},
1593 print $ArtistOne->name; ## response is 'Artist One'
1594 print $ArtistThree->cds->count ## reponse is '2'
1596 For the arrayref of arrayrefs style, the first element should be a list of the
1597 fieldsnames to which the remaining elements are rows being inserted. For
1600 $Arstist_rs->populate([
1601 [qw/artistid name/],
1602 [100, 'A Formally Unknown Singer'],
1603 [101, 'A singer that jumped the shark two albums ago'],
1604 [102, 'An actually cool singer.'],
1607 Please note an important effect on your data when choosing between void and
1608 wantarray context. Since void context goes straight to C<insert_bulk> in
1609 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
1610 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
1611 create primary keys for you, you will find that your PKs are empty. In this
1612 case you will have to use the wantarray context in order to create those
1620 # cruft placed in standalone method
1621 my $data = $self->_normalize_populate_args(@_);
1623 if(defined wantarray) {
1625 foreach my $item (@$data) {
1626 push(@created, $self->create($item));
1628 return wantarray ? @created : \@created;
1630 my $first = $data->[0];
1632 # if a column is a registered relationship, and is a non-blessed hash/array, consider
1633 # it relationship data
1634 my (@rels, @columns);
1635 for (keys %$first) {
1636 my $ref = ref $first->{$_};
1637 $self->result_source->has_relationship($_) && ($ref eq 'ARRAY' or $ref eq 'HASH')
1643 my @pks = $self->result_source->primary_columns;
1645 ## do the belongs_to relationships
1646 foreach my $index (0..$#$data) {
1648 # delegate to create() for any dataset without primary keys with specified relationships
1649 if (grep { !defined $data->[$index]->{$_} } @pks ) {
1651 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
1652 my @ret = $self->populate($data);
1658 foreach my $rel (@rels) {
1659 next unless ref $data->[$index]->{$rel} eq "HASH";
1660 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1661 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1662 my $related = $result->result_source->_resolve_condition(
1663 $result->result_source->relationship_info($reverse)->{cond},
1668 delete $data->[$index]->{$rel};
1669 $data->[$index] = {%{$data->[$index]}, %$related};
1671 push @columns, keys %$related if $index == 0;
1675 ## inherit the data locked in the conditions of the resultset
1676 my ($rs_data) = $self->_merge_cond_with_data({});
1677 delete @{$rs_data}{@columns};
1678 my @inherit_cols = keys %$rs_data;
1679 my @inherit_data = values %$rs_data;
1681 ## do bulk insert on current row
1682 $self->result_source->storage->insert_bulk(
1683 $self->result_source,
1684 [@columns, @inherit_cols],
1685 [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
1688 ## do the has_many relationships
1689 foreach my $item (@$data) {
1691 foreach my $rel (@rels) {
1692 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1694 my $parent = $self->find({map { $_ => $item->{$_} } @pks})
1695 || $self->throw_exception('Cannot find the relating object.');
1697 my $child = $parent->$rel;
1699 my $related = $child->result_source->_resolve_condition(
1700 $parent->result_source->relationship_info($rel)->{cond},
1705 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1706 my @populate = map { {%$_, %$related} } @rows_to_add;
1708 $child->populate( \@populate );
1715 # populate() argumnets went over several incarnations
1716 # What we ultimately support is AoH
1717 sub _normalize_populate_args {
1718 my ($self, $arg) = @_;
1720 if (ref $arg eq 'ARRAY') {
1721 if (ref $arg->[0] eq 'HASH') {
1724 elsif (ref $arg->[0] eq 'ARRAY') {
1726 my @colnames = @{$arg->[0]};
1727 foreach my $values (@{$arg}[1 .. $#$arg]) {
1728 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
1734 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
1741 =item Arguments: none
1743 =item Return Value: $pager
1747 Return Value a L<Data::Page> object for the current resultset. Only makes
1748 sense for queries with a C<page> attribute.
1750 To get the full count of entries for a paged resultset, call
1751 C<total_entries> on the L<Data::Page> object.
1758 return $self->{pager} if $self->{pager};
1760 my $attrs = $self->{attrs};
1761 $self->throw_exception("Can't create pager for non-paged rs")
1762 unless $self->{attrs}{page};
1763 $attrs->{rows} ||= 10;
1765 # throw away the paging flags and re-run the count (possibly
1766 # with a subselect) to get the real total count
1767 my $count_attrs = { %$attrs };
1768 delete $count_attrs->{$_} for qw/rows offset page pager/;
1769 my $total_count = (ref $self)->new($self->result_source, $count_attrs)->count;
1771 return $self->{pager} = Data::Page->new(
1774 $self->{attrs}{page}
1782 =item Arguments: $page_number
1784 =item Return Value: $rs
1788 Returns a resultset for the $page_number page of the resultset on which page
1789 is called, where each page contains a number of rows equal to the 'rows'
1790 attribute set on the resultset (10 by default).
1795 my ($self, $page) = @_;
1796 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1803 =item Arguments: \%vals
1805 =item Return Value: $rowobject
1809 Creates a new row object in the resultset's result class and returns
1810 it. The row is not inserted into the database at this point, call
1811 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
1812 will tell you whether the row object has been inserted or not.
1814 Passes the hashref of input on to L<DBIx::Class::Row/new>.
1819 my ($self, $values) = @_;
1820 $self->throw_exception( "new_result needs a hash" )
1821 unless (ref $values eq 'HASH');
1823 my ($merged_cond, $cols_from_relations) = $self->_merge_cond_with_data($values);
1827 @$cols_from_relations
1828 ? (-cols_from_relations => $cols_from_relations)
1830 -source_handle => $self->_source_handle,
1831 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
1834 return $self->result_class->new(\%new);
1837 # _merge_cond_with_data
1839 # Takes a simple hash of K/V data and returns its copy merged with the
1840 # condition already present on the resultset. Additionally returns an
1841 # arrayref of value/condition names, which were inferred from related
1842 # objects (this is needed for in-memory related objects)
1843 sub _merge_cond_with_data {
1844 my ($self, $data) = @_;
1846 my (%new_data, @cols_from_relations);
1848 my $alias = $self->{attrs}{alias};
1850 if (! defined $self->{cond}) {
1851 # just massage $data below
1853 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
1854 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
1855 @cols_from_relations = keys %new_data;
1857 elsif (ref $self->{cond} ne 'HASH') {
1858 $self->throw_exception(
1859 "Can't abstract implicit construct, resultset condition not a hash"
1863 # precendence must be given to passed values over values inherited from
1864 # the cond, so the order here is important.
1865 my $collapsed_cond = $self->_collapse_cond($self->{cond});
1866 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
1868 while ( my($col, $value) = each %implied ) {
1869 if (ref($value) eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '=') {
1870 $new_data{$col} = $value->{'='};
1873 $new_data{$col} = $value if $self->_is_deterministic_value($value);
1879 %{ $self->_remove_alias($data, $alias) },
1882 return (\%new_data, \@cols_from_relations);
1885 # _is_deterministic_value
1887 # Make an effor to strip non-deterministic values from the condition,
1888 # to make sure new_result chokes less
1890 sub _is_deterministic_value {
1893 my $ref_type = ref $value;
1894 return 1 if $ref_type eq '' || $ref_type eq 'SCALAR';
1895 return 1 if Scalar::Util::blessed($value);
1899 # _has_resolved_attr
1901 # determines if the resultset defines at least one
1902 # of the attributes supplied
1904 # used to determine if a subquery is neccessary
1906 # supports some virtual attributes:
1908 # This will scan for any joins being present on the resultset.
1909 # It is not a mere key-search but a deep inspection of {from}
1912 sub _has_resolved_attr {
1913 my ($self, @attr_names) = @_;
1915 my $attrs = $self->_resolved_attrs;
1919 for my $n (@attr_names) {
1920 if (grep { $n eq $_ } (qw/-join/) ) {
1921 $extra_checks{$n}++;
1925 my $attr = $attrs->{$n};
1927 next if not defined $attr;
1929 if (ref $attr eq 'HASH') {
1930 return 1 if keys %$attr;
1932 elsif (ref $attr eq 'ARRAY') {
1940 # a resolved join is expressed as a multi-level from
1942 $extra_checks{-join}
1944 ref $attrs->{from} eq 'ARRAY'
1946 @{$attrs->{from}} > 1
1954 # Recursively collapse the condition.
1956 sub _collapse_cond {
1957 my ($self, $cond, $collapsed) = @_;
1961 if (ref $cond eq 'ARRAY') {
1962 foreach my $subcond (@$cond) {
1963 next unless ref $subcond; # -or
1964 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1967 elsif (ref $cond eq 'HASH') {
1968 if (keys %$cond and (keys %$cond)[0] eq '-and') {
1969 foreach my $subcond (@{$cond->{-and}}) {
1970 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1974 foreach my $col (keys %$cond) {
1975 my $value = $cond->{$col};
1976 $collapsed->{$col} = $value;
1986 # Remove the specified alias from the specified query hash. A copy is made so
1987 # the original query is not modified.
1990 my ($self, $query, $alias) = @_;
1992 my %orig = %{ $query || {} };
1995 foreach my $key (keys %orig) {
1997 $unaliased{$key} = $orig{$key};
2000 $unaliased{$1} = $orig{$key}
2001 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2011 =item Arguments: none
2013 =item Return Value: \[ $sql, @bind ]
2017 Returns the SQL query and bind vars associated with the invocant.
2019 This is generally used as the RHS for a subquery.
2026 my $attrs = $self->_resolved_attrs_copy;
2031 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2032 # $sql also has no wrapping parenthesis in list ctx
2034 my $sqlbind = $self->result_source->storage
2035 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2044 =item Arguments: \%vals, \%attrs?
2046 =item Return Value: $rowobject
2050 my $artist = $schema->resultset('Artist')->find_or_new(
2051 { artist => 'fred' }, { key => 'artists' });
2053 $cd->cd_to_producer->find_or_new({ producer => $producer },
2054 { key => 'primary });
2056 Find an existing record from this resultset, based on its primary
2057 key, or a unique constraint. If none exists, instantiate a new result
2058 object and return it. The object will not be saved into your storage
2059 until you call L<DBIx::Class::Row/insert> on it.
2061 You most likely want this method when looking for existing rows using
2062 a unique constraint that is not the primary key, or looking for
2065 If you want objects to be saved immediately, use L</find_or_create>
2068 B<Note>: Take care when using C<find_or_new> with a table having
2069 columns with default values that you intend to be automatically
2070 supplied by the database (e.g. an auto_increment primary key column).
2071 In normal usage, the value of such columns should NOT be included at
2072 all in the call to C<find_or_new>, even when set to C<undef>.
2078 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2079 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2080 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2083 return $self->new_result($hash);
2090 =item Arguments: \%vals
2092 =item Return Value: a L<DBIx::Class::Row> $object
2096 Attempt to create a single new row or a row with multiple related rows
2097 in the table represented by the resultset (and related tables). This
2098 will not check for duplicate rows before inserting, use
2099 L</find_or_create> to do that.
2101 To create one row for this resultset, pass a hashref of key/value
2102 pairs representing the columns of the table and the values you wish to
2103 store. If the appropriate relationships are set up, foreign key fields
2104 can also be passed an object representing the foreign row, and the
2105 value will be set to its primary key.
2107 To create related objects, pass a hashref of related-object column values
2108 B<keyed on the relationship name>. If the relationship is of type C<multi>
2109 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2110 The process will correctly identify columns holding foreign keys, and will
2111 transparrently populate them from the keys of the corresponding relation.
2112 This can be applied recursively, and will work correctly for a structure
2113 with an arbitrary depth and width, as long as the relationships actually
2114 exists and the correct column data has been supplied.
2117 Instead of hashrefs of plain related data (key/value pairs), you may
2118 also pass new or inserted objects. New objects (not inserted yet, see
2119 L</new>), will be inserted into their appropriate tables.
2121 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2123 Example of creating a new row.
2125 $person_rs->create({
2126 name=>"Some Person",
2127 email=>"somebody@someplace.com"
2130 Example of creating a new row and also creating rows in a related C<has_many>
2131 or C<has_one> resultset. Note Arrayref.
2134 { artistid => 4, name => 'Manufactured Crap', cds => [
2135 { title => 'My First CD', year => 2006 },
2136 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2141 Example of creating a new row and also creating a row in a related
2142 C<belongs_to>resultset. Note Hashref.
2145 title=>"Music for Silly Walks",
2148 name=>"Silly Musician",
2156 When subclassing ResultSet never attempt to override this method. Since
2157 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2158 lot of the internals simply never call it, so your override will be
2159 bypassed more often than not. Override either L<new|DBIx::Class::Row/new>
2160 or L<insert|DBIx::Class::Row/insert> depending on how early in the
2161 L</create> process you need to intervene.
2168 my ($self, $attrs) = @_;
2169 $self->throw_exception( "create needs a hashref" )
2170 unless ref $attrs eq 'HASH';
2171 return $self->new_result($attrs)->insert;
2174 =head2 find_or_create
2178 =item Arguments: \%vals, \%attrs?
2180 =item Return Value: $rowobject
2184 $cd->cd_to_producer->find_or_create({ producer => $producer },
2185 { key => 'primary' });
2187 Tries to find a record based on its primary key or unique constraints; if none
2188 is found, creates one and returns that instead.
2190 my $cd = $schema->resultset('CD')->find_or_create({
2192 artist => 'Massive Attack',
2193 title => 'Mezzanine',
2197 Also takes an optional C<key> attribute, to search by a specific key or unique
2198 constraint. For example:
2200 my $cd = $schema->resultset('CD')->find_or_create(
2202 artist => 'Massive Attack',
2203 title => 'Mezzanine',
2205 { key => 'cd_artist_title' }
2208 B<Note>: Because find_or_create() reads from the database and then
2209 possibly inserts based on the result, this method is subject to a race
2210 condition. Another process could create a record in the table after
2211 the find has completed and before the create has started. To avoid
2212 this problem, use find_or_create() inside a transaction.
2214 B<Note>: Take care when using C<find_or_create> with a table having
2215 columns with default values that you intend to be automatically
2216 supplied by the database (e.g. an auto_increment primary key column).
2217 In normal usage, the value of such columns should NOT be included at
2218 all in the call to C<find_or_create>, even when set to C<undef>.
2220 See also L</find> and L</update_or_create>. For information on how to declare
2221 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2225 sub find_or_create {
2227 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2228 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2229 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2232 return $self->create($hash);
2235 =head2 update_or_create
2239 =item Arguments: \%col_values, { key => $unique_constraint }?
2241 =item Return Value: $rowobject
2245 $resultset->update_or_create({ col => $val, ... });
2247 First, searches for an existing row matching one of the unique constraints
2248 (including the primary key) on the source of this resultset. If a row is
2249 found, updates it with the other given column values. Otherwise, creates a new
2252 Takes an optional C<key> attribute to search on a specific unique constraint.
2255 # In your application
2256 my $cd = $schema->resultset('CD')->update_or_create(
2258 artist => 'Massive Attack',
2259 title => 'Mezzanine',
2262 { key => 'cd_artist_title' }
2265 $cd->cd_to_producer->update_or_create({
2266 producer => $producer,
2273 If no C<key> is specified, it searches on all unique constraints defined on the
2274 source, including the primary key.
2276 If the C<key> is specified as C<primary>, it searches only on the primary key.
2278 See also L</find> and L</find_or_create>. For information on how to declare
2279 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2281 B<Note>: Take care when using C<update_or_create> with a table having
2282 columns with default values that you intend to be automatically
2283 supplied by the database (e.g. an auto_increment primary key column).
2284 In normal usage, the value of such columns should NOT be included at
2285 all in the call to C<update_or_create>, even when set to C<undef>.
2289 sub update_or_create {
2291 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2292 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2294 my $row = $self->find($cond, $attrs);
2296 $row->update($cond);
2300 return $self->create($cond);
2303 =head2 update_or_new
2307 =item Arguments: \%col_values, { key => $unique_constraint }?
2309 =item Return Value: $rowobject
2313 $resultset->update_or_new({ col => $val, ... });
2315 First, searches for an existing row matching one of the unique constraints
2316 (including the primary key) on the source of this resultset. If a row is
2317 found, updates it with the other given column values. Otherwise, instantiate
2318 a new result object and return it. The object will not be saved into your storage
2319 until you call L<DBIx::Class::Row/insert> on it.
2321 Takes an optional C<key> attribute to search on a specific unique constraint.
2324 # In your application
2325 my $cd = $schema->resultset('CD')->update_or_new(
2327 artist => 'Massive Attack',
2328 title => 'Mezzanine',
2331 { key => 'cd_artist_title' }
2334 if ($cd->in_storage) {
2335 # the cd was updated
2338 # the cd is not yet in the database, let's insert it
2342 B<Note>: Take care when using C<update_or_new> with a table having
2343 columns with default values that you intend to be automatically
2344 supplied by the database (e.g. an auto_increment primary key column).
2345 In normal usage, the value of such columns should NOT be included at
2346 all in the call to C<update_or_new>, even when set to C<undef>.
2348 See also L</find>, L</find_or_create> and L</find_or_new>.
2354 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2355 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2357 my $row = $self->find( $cond, $attrs );
2358 if ( defined $row ) {
2359 $row->update($cond);
2363 return $self->new_result($cond);
2370 =item Arguments: none
2372 =item Return Value: \@cache_objects?
2376 Gets the contents of the cache for the resultset, if the cache is set.
2378 The cache is populated either by using the L</prefetch> attribute to
2379 L</search> or by calling L</set_cache>.
2391 =item Arguments: \@cache_objects
2393 =item Return Value: \@cache_objects
2397 Sets the contents of the cache for the resultset. Expects an arrayref
2398 of objects of the same class as those produced by the resultset. Note that
2399 if the cache is set the resultset will return the cached objects rather
2400 than re-querying the database even if the cache attr is not set.
2402 The contents of the cache can also be populated by using the
2403 L</prefetch> attribute to L</search>.
2408 my ( $self, $data ) = @_;
2409 $self->throw_exception("set_cache requires an arrayref")
2410 if defined($data) && (ref $data ne 'ARRAY');
2411 $self->{all_cache} = $data;
2418 =item Arguments: none
2420 =item Return Value: []
2424 Clears the cache for the resultset.
2429 shift->set_cache(undef);
2436 =item Arguments: none
2438 =item Return Value: true, if the resultset has been paginated
2446 return !!$self->{attrs}{page};
2453 =item Arguments: none
2455 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2463 return scalar $self->result_source->storage->_parse_order_by($self->{attrs}{order_by});
2466 =head2 related_resultset
2470 =item Arguments: $relationship_name
2472 =item Return Value: $resultset
2476 Returns a related resultset for the supplied relationship name.
2478 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2482 sub related_resultset {
2483 my ($self, $rel) = @_;
2485 $self->{related_resultsets} ||= {};
2486 return $self->{related_resultsets}{$rel} ||= do {
2487 my $rsrc = $self->result_source;
2488 my $rel_info = $rsrc->relationship_info($rel);
2490 $self->throw_exception(
2491 "search_related: result source '" . $rsrc->source_name .
2492 "' has no such relationship $rel")
2495 my $attrs = $self->_chain_relationship($rel);
2497 my $join_count = $attrs->{seen_join}{$rel};
2499 my $alias = $self->result_source->storage
2500 ->relname_to_table_alias($rel, $join_count);
2502 # since this is search_related, and we already slid the select window inwards
2503 # (the select/as attrs were deleted in the beginning), we need to flip all
2504 # left joins to inner, so we get the expected results
2505 # read the comment on top of the actual function to see what this does
2506 $attrs->{from} = $rsrc->schema->storage->_straight_join_to_node ($attrs->{from}, $alias);
2509 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2510 delete @{$attrs}{qw(result_class alias)};
2514 if (my $cache = $self->get_cache) {
2515 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2516 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
2521 my $rel_source = $rsrc->related_source($rel);
2525 # The reason we do this now instead of passing the alias to the
2526 # search_rs below is that if you wrap/overload resultset on the
2527 # source you need to know what alias it's -going- to have for things
2528 # to work sanely (e.g. RestrictWithObject wants to be able to add
2529 # extra query restrictions, and these may need to be $alias.)
2531 my $rel_attrs = $rel_source->resultset_attributes;
2532 local $rel_attrs->{alias} = $alias;
2534 $rel_source->resultset
2538 where => $attrs->{where},
2541 $new->set_cache($new_cache) if $new_cache;
2546 =head2 current_source_alias
2550 =item Arguments: none
2552 =item Return Value: $source_alias
2556 Returns the current table alias for the result source this resultset is built
2557 on, that will be used in the SQL query. Usually it is C<me>.
2559 Currently the source alias that refers to the result set returned by a
2560 L</search>/L</find> family method depends on how you got to the resultset: it's
2561 C<me> by default, but eg. L</search_related> aliases it to the related result
2562 source name (and keeps C<me> referring to the original result set). The long
2563 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
2564 (and make this method unnecessary).
2566 Thus it's currently necessary to use this method in predefined queries (see
2567 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
2568 source alias of the current result set:
2570 # in a result set class
2572 my ($self, $user) = @_;
2574 my $me = $self->current_source_alias;
2576 return $self->search(
2577 "$me.modified" => $user->id,
2583 sub current_source_alias {
2586 return ($self->{attrs} || {})->{alias} || 'me';
2589 =head2 as_subselect_rs
2593 =item Arguments: none
2595 =item Return Value: $resultset
2599 Act as a barrier to SQL symbols. The resultset provided will be made into a
2600 "virtual view" by including it as a subquery within the from clause. From this
2601 point on, any joined tables are inaccessible to ->search on the resultset (as if
2602 it were simply where-filtered without joins). For example:
2604 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
2606 # 'x' now pollutes the query namespace
2608 # So the following works as expected
2609 my $ok_rs = $rs->search({'x.other' => 1});
2611 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
2612 # def) we look for one row with contradictory terms and join in another table
2613 # (aliased 'x_2') which we never use
2614 my $broken_rs = $rs->search({'x.name' => 'def'});
2616 my $rs2 = $rs->as_subselect_rs;
2618 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
2619 my $not_joined_rs = $rs2->search({'x.other' => 1});
2621 # works as expected: finds a 'table' row related to two x rows (abc and def)
2622 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
2624 Another example of when one might use this would be to select a subset of
2625 columns in a group by clause:
2627 my $rs = $schema->resultset('Bar')->search(undef, {
2628 group_by => [qw{ id foo_id baz_id }],
2629 })->as_subselect_rs->search(undef, {
2630 columns => [qw{ id foo_id }]
2633 In the above example normally columns would have to be equal to the group by,
2634 but because we isolated the group by into a subselect the above works.
2638 sub as_subselect_rs {
2641 return $self->result_source->resultset->search( undef, {
2642 alias => $self->current_source_alias,
2644 $self->current_source_alias => $self->as_query,
2645 -alias => $self->current_source_alias,
2646 -source_handle => $self->result_source->handle,
2651 # This code is called by search_related, and makes sure there
2652 # is clear separation between the joins before, during, and
2653 # after the relationship. This information is needed later
2654 # in order to properly resolve prefetch aliases (any alias
2655 # with a relation_chain_depth less than the depth of the
2656 # current prefetch is not considered)
2658 # The increments happen twice per join. An even number means a
2659 # relationship specified via a search_related, whereas an odd
2660 # number indicates a join/prefetch added via attributes
2662 # Also this code will wrap the current resultset (the one we
2663 # chain to) in a subselect IFF it contains limiting attributes
2664 sub _chain_relationship {
2665 my ($self, $rel) = @_;
2666 my $source = $self->result_source;
2667 my $attrs = { %{$self->{attrs}||{}} };
2669 # we need to take the prefetch the attrs into account before we
2670 # ->_resolve_join as otherwise they get lost - captainL
2671 my $join = $self->_merge_attr( $attrs->{join}, $attrs->{prefetch} );
2673 delete @{$attrs}{qw/join prefetch collapse distinct select as columns +select +as +columns/};
2675 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
2678 my @force_subq_attrs = qw/offset rows group_by having/;
2681 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
2683 $self->_has_resolved_attr (@force_subq_attrs)
2685 # Nuke the prefetch (if any) before the new $rs attrs
2686 # are resolved (prefetch is useless - we are wrapping
2687 # a subquery anyway).
2688 my $rs_copy = $self->search;
2689 $rs_copy->{attrs}{join} = $self->_merge_attr (
2690 $rs_copy->{attrs}{join},
2691 delete $rs_copy->{attrs}{prefetch},
2695 -source_handle => $source->handle,
2696 -alias => $attrs->{alias},
2697 $attrs->{alias} => $rs_copy->as_query,
2699 delete @{$attrs}{@force_subq_attrs, 'where'};
2700 $seen->{-relation_chain_depth} = 0;
2702 elsif ($attrs->{from}) { #shallow copy suffices
2703 $from = [ @{$attrs->{from}} ];
2707 -source_handle => $source->handle,
2708 -alias => $attrs->{alias},
2709 $attrs->{alias} => $source->from,
2713 my $jpath = ($seen->{-relation_chain_depth})
2714 ? $from->[-1][0]{-join_path}
2717 my @requested_joins = $source->_resolve_join(
2724 push @$from, @requested_joins;
2726 $seen->{-relation_chain_depth}++;
2728 # if $self already had a join/prefetch specified on it, the requested
2729 # $rel might very well be already included. What we do in this case
2730 # is effectively a no-op (except that we bump up the chain_depth on
2731 # the join in question so we could tell it *is* the search_related)
2734 # we consider the last one thus reverse
2735 for my $j (reverse @requested_joins) {
2736 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
2737 if ($rel eq $last_j) {
2738 $j->[0]{-relation_chain_depth}++;
2744 unless ($already_joined) {
2745 push @$from, $source->_resolve_join(
2753 $seen->{-relation_chain_depth}++;
2755 return {%$attrs, from => $from, seen_join => $seen};
2758 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
2759 sub _resolved_attrs_copy {
2761 return { %{$self->_resolved_attrs (@_)} };
2764 sub _resolved_attrs {
2766 return $self->{_attrs} if $self->{_attrs};
2768 my $attrs = { %{ $self->{attrs} || {} } };
2769 my $source = $self->result_source;
2770 my $alias = $attrs->{alias};
2772 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
2775 # build columns (as long as select isn't set) into a set of as/select hashes
2776 unless ( $attrs->{select} ) {
2779 if ( ref $attrs->{columns} eq 'ARRAY' ) {
2780 @cols = @{ delete $attrs->{columns}}
2781 } elsif ( defined $attrs->{columns} ) {
2782 @cols = delete $attrs->{columns}
2784 @cols = $source->columns
2788 if ( ref $_ eq 'HASH' ) {
2791 my $key = /^\Q${alias}.\E(.+)$/
2797 push @colbits, { $key => $value };
2802 # add the additional columns on
2803 foreach (qw{include_columns +columns}) {
2804 if ( $attrs->{$_} ) {
2805 my @list = ( ref($attrs->{$_}) eq 'ARRAY' )
2806 ? @{ delete $attrs->{$_} }
2807 : delete $attrs->{$_};
2809 if ( ref($_) eq 'HASH' ) {
2812 my $key = ( split /\./, $_ )[-1];
2813 my $value = ( /\./ ? $_ : "$alias.$_" );
2814 push @colbits, { $key => $value };
2820 # start with initial select items
2821 if ( $attrs->{select} ) {
2823 ( ref $attrs->{select} eq 'ARRAY' )
2824 ? [ @{ $attrs->{select} } ]
2825 : [ $attrs->{select} ];
2827 if ( $attrs->{as} ) {
2830 ref $attrs->{as} eq 'ARRAY'
2831 ? [ @{ $attrs->{as} } ]
2835 $attrs->{as} = [ map {
2836 m/^\Q${alias}.\E(.+)$/
2839 } @{ $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 $attrs->{collapse} ||= {};
2935 if ( my $prefetch = delete $attrs->{prefetch} ) {
2936 $prefetch = $self->_merge_attr( {}, $prefetch );
2938 my $prefetch_ordering = [];
2940 # this is a separate structure (we don't look in {from} directly)
2941 # as the resolver needs to shift things off the lists to work
2942 # properly (identical-prefetches on different branches)
2944 if (ref $attrs->{from} eq 'ARRAY') {
2946 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
2948 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
2949 next unless $j->[0]{-alias};
2950 next unless $j->[0]{-join_path};
2951 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
2953 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
2956 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
2957 push @{$p->{-join_aliases} }, $j->[0]{-alias};
2962 $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
2964 # we need to somehow mark which columns came from prefetch
2965 $attrs->{_prefetch_select} = [ map { $_->[0] } @prefetch ];
2967 push @{ $attrs->{select} }, @{$attrs->{_prefetch_select}};
2968 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
2970 push( @{$attrs->{order_by}}, @$prefetch_ordering );
2971 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
2974 # if both page and offset are specified, produce a combined offset
2975 # even though it doesn't make much sense, this is what pre 081xx has
2977 if (my $page = delete $attrs->{page}) {
2979 ($attrs->{rows} * ($page - 1))
2981 ($attrs->{offset} || 0)
2985 return $self->{_attrs} = $attrs;
2989 my ($self, $attr) = @_;
2991 if (ref $attr eq 'HASH') {
2992 return $self->_rollout_hash($attr);
2993 } elsif (ref $attr eq 'ARRAY') {
2994 return $self->_rollout_array($attr);
3000 sub _rollout_array {
3001 my ($self, $attr) = @_;
3004 foreach my $element (@{$attr}) {
3005 if (ref $element eq 'HASH') {
3006 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3007 } elsif (ref $element eq 'ARRAY') {
3008 # XXX - should probably recurse here
3009 push( @rolled_array, @{$self->_rollout_array($element)} );
3011 push( @rolled_array, $element );
3014 return \@rolled_array;
3018 my ($self, $attr) = @_;
3021 foreach my $key (keys %{$attr}) {
3022 push( @rolled_array, { $key => $attr->{$key} } );
3024 return \@rolled_array;
3027 sub _calculate_score {
3028 my ($self, $a, $b) = @_;
3030 if (defined $a xor defined $b) {
3033 elsif (not defined $a) {
3037 if (ref $b eq 'HASH') {
3038 my ($b_key) = keys %{$b};
3039 if (ref $a eq 'HASH') {
3040 my ($a_key) = keys %{$a};
3041 if ($a_key eq $b_key) {
3042 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3047 return ($a eq $b_key) ? 1 : 0;
3050 if (ref $a eq 'HASH') {
3051 my ($a_key) = keys %{$a};
3052 return ($b eq $a_key) ? 1 : 0;
3054 return ($b eq $a) ? 1 : 0;
3060 my ($self, $orig, $import) = @_;
3062 return $import unless defined($orig);
3063 return $orig unless defined($import);
3065 $orig = $self->_rollout_attr($orig);
3066 $import = $self->_rollout_attr($import);
3069 foreach my $import_element ( @{$import} ) {
3070 # find best candidate from $orig to merge $b_element into
3071 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3072 foreach my $orig_element ( @{$orig} ) {
3073 my $score = $self->_calculate_score( $orig_element, $import_element );
3074 if ($score > $best_candidate->{score}) {
3075 $best_candidate->{position} = $position;
3076 $best_candidate->{score} = $score;
3080 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3082 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3083 push( @{$orig}, $import_element );
3085 my $orig_best = $orig->[$best_candidate->{position}];
3086 # merge orig_best and b_element together and replace original with merged
3087 if (ref $orig_best ne 'HASH') {
3088 $orig->[$best_candidate->{position}] = $import_element;
3089 } elsif (ref $import_element eq 'HASH') {
3090 my ($key) = keys %{$orig_best};
3091 $orig->[$best_candidate->{position}] = { $key => $self->_merge_attr($orig_best->{$key}, $import_element->{$key}) };
3094 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3104 $self->_source_handle($_[0]->handle);
3106 $self->_source_handle->resolve;
3110 =head2 throw_exception
3112 See L<DBIx::Class::Schema/throw_exception> for details.
3116 sub throw_exception {
3119 if (ref $self && $self->_source_handle->schema) {
3120 $self->_source_handle->schema->throw_exception(@_)
3123 DBIx::Class::Exception->throw(@_);
3127 # XXX: FIXME: Attributes docs need clearing up
3131 Attributes are used to refine a ResultSet in various ways when
3132 searching for data. They can be passed to any method which takes an
3133 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3136 These are in no particular order:
3142 =item Value: ( $order_by | \@order_by | \%order_by )
3146 Which column(s) to order the results by.
3148 [The full list of suitable values is documented in
3149 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3152 If a single column name, or an arrayref of names is supplied, the
3153 argument is passed through directly to SQL. The hashref syntax allows
3154 for connection-agnostic specification of ordering direction:
3156 For descending order:
3158 order_by => { -desc => [qw/col1 col2 col3/] }
3160 For explicit ascending order:
3162 order_by => { -asc => 'col' }
3164 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3165 supported, although you are strongly encouraged to use the hashref
3166 syntax as outlined above.
3172 =item Value: \@columns
3176 Shortcut to request a particular set of columns to be retrieved. Each
3177 column spec may be a string (a table column name), or a hash (in which
3178 case the key is the C<as> value, and the value is used as the C<select>
3179 expression). Adds C<me.> onto the start of any column without a C<.> in
3180 it and sets C<select> from that, then auto-populates C<as> from
3181 C<select> as normal. (You may also use the C<cols> attribute, as in
3182 earlier versions of DBIC.)
3188 =item Value: \@columns
3192 Indicates additional columns to be selected from storage. Works the same
3193 as L</columns> but adds columns to the selection. (You may also use the
3194 C<include_columns> attribute, as in earlier versions of DBIC). For
3197 $schema->resultset('CD')->search(undef, {
3198 '+columns' => ['artist.name'],
3202 would return all CDs and include a 'name' column to the information
3203 passed to object inflation. Note that the 'artist' is the name of the
3204 column (or relationship) accessor, and 'name' is the name of the column
3205 accessor in the related table.
3207 =head2 include_columns
3211 =item Value: \@columns
3215 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3221 =item Value: \@select_columns
3225 Indicates which columns should be selected from the storage. You can use
3226 column names, or in the case of RDBMS back ends, function or stored procedure
3229 $rs = $schema->resultset('Employee')->search(undef, {
3232 { count => 'employeeid' },
3237 When you use function/stored procedure names and do not supply an C<as>
3238 attribute, the column names returned are storage-dependent. E.g. MySQL would
3239 return a column named C<count(employeeid)> in the above example.
3241 B<NOTE:> You will almost always need a corresponding 'as' entry when you use
3248 Indicates additional columns to be selected from storage. Works the same as
3249 L</select> but adds columns to the selection.
3257 Indicates additional column names for those added via L</+select>. See L</as>.
3265 =item Value: \@inflation_names
3269 Indicates column names for object inflation. That is, C<as>
3270 indicates the name that the column can be accessed as via the
3271 C<get_column> method (or via the object accessor, B<if one already
3272 exists>). It has nothing to do with the SQL code C<SELECT foo AS bar>.
3274 The C<as> attribute is used in conjunction with C<select>,
3275 usually when C<select> contains one or more function or stored
3278 $rs = $schema->resultset('Employee')->search(undef, {
3281 { count => 'employeeid' }
3283 as => ['name', 'employee_count'],
3286 my $employee = $rs->first(); # get the first Employee
3288 If the object against which the search is performed already has an accessor
3289 matching a column name specified in C<as>, the value can be retrieved using
3290 the accessor as normal:
3292 my $name = $employee->name();
3294 If on the other hand an accessor does not exist in the object, you need to
3295 use C<get_column> instead:
3297 my $employee_count = $employee->get_column('employee_count');
3299 You can create your own accessors if required - see
3300 L<DBIx::Class::Manual::Cookbook> for details.
3302 Please note: This will NOT insert an C<AS employee_count> into the SQL
3303 statement produced, it is used for internal access only. Thus
3304 attempting to use the accessor in an C<order_by> clause or similar
3305 will fail miserably.
3307 To get around this limitation, you can supply literal SQL to your
3308 C<select> attibute that contains the C<AS alias> text, eg:
3310 select => [\'myfield AS alias']
3316 =item Value: ($rel_name | \@rel_names | \%rel_names)
3320 Contains a list of relationships that should be joined for this query. For
3323 # Get CDs by Nine Inch Nails
3324 my $rs = $schema->resultset('CD')->search(
3325 { 'artist.name' => 'Nine Inch Nails' },
3326 { join => 'artist' }
3329 Can also contain a hash reference to refer to the other relation's relations.
3332 package MyApp::Schema::Track;
3333 use base qw/DBIx::Class/;
3334 __PACKAGE__->table('track');
3335 __PACKAGE__->add_columns(qw/trackid cd position title/);
3336 __PACKAGE__->set_primary_key('trackid');
3337 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3340 # In your application
3341 my $rs = $schema->resultset('Artist')->search(
3342 { 'track.title' => 'Teardrop' },
3344 join => { cd => 'track' },
3345 order_by => 'artist.name',
3349 You need to use the relationship (not the table) name in conditions,
3350 because they are aliased as such. The current table is aliased as "me", so
3351 you need to use me.column_name in order to avoid ambiguity. For example:
3353 # Get CDs from 1984 with a 'Foo' track
3354 my $rs = $schema->resultset('CD')->search(
3357 'tracks.name' => 'Foo'
3359 { join => 'tracks' }
3362 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3363 similarly for a third time). For e.g.
3365 my $rs = $schema->resultset('Artist')->search({
3366 'cds.title' => 'Down to Earth',
3367 'cds_2.title' => 'Popular',
3369 join => [ qw/cds cds/ ],
3372 will return a set of all artists that have both a cd with title 'Down
3373 to Earth' and a cd with title 'Popular'.
3375 If you want to fetch related objects from other tables as well, see C<prefetch>
3378 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3384 =item Value: ($rel_name | \@rel_names | \%rel_names)
3388 Contains one or more relationships that should be fetched along with
3389 the main query (when they are accessed afterwards the data will
3390 already be available, without extra queries to the database). This is
3391 useful for when you know you will need the related objects, because it
3392 saves at least one query:
3394 my $rs = $schema->resultset('Tag')->search(
3403 The initial search results in SQL like the following:
3405 SELECT tag.*, cd.*, artist.* FROM tag
3406 JOIN cd ON tag.cd = cd.cdid
3407 JOIN artist ON cd.artist = artist.artistid
3409 L<DBIx::Class> has no need to go back to the database when we access the
3410 C<cd> or C<artist> relationships, which saves us two SQL statements in this
3413 Simple prefetches will be joined automatically, so there is no need
3414 for a C<join> attribute in the above search.
3416 C<prefetch> can be used with the following relationship types: C<belongs_to>,
3417 C<has_one> (or if you're using C<add_relationship>, any relationship declared
3418 with an accessor type of 'single' or 'filter'). A more complex example that
3419 prefetches an artists cds, the tracks on those cds, and the tags associted
3420 with that artist is given below (assuming many-to-many from artists to tags):
3422 my $rs = $schema->resultset('Artist')->search(
3426 { cds => 'tracks' },
3427 { artist_tags => 'tags' }
3433 B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
3434 attributes will be ignored.
3436 B<CAVEATs>: Prefetch does a lot of deep magic. As such, it may not behave
3437 exactly as you might expect.
3443 Prefetch uses the L</cache> to populate the prefetched relationships. This
3444 may or may not be what you want.
3448 If you specify a condition on a prefetched relationship, ONLY those
3449 rows that match the prefetched condition will be fetched into that relationship.
3450 This means that adding prefetch to a search() B<may alter> what is returned by
3451 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
3453 my $artist_rs = $schema->resultset('Artist')->search({
3459 my $count = $artist_rs->first->cds->count;
3461 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
3463 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
3465 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
3467 that cmp_ok() may or may not pass depending on the datasets involved. This
3468 behavior may or may not survive the 0.09 transition.
3480 Makes the resultset paged and specifies the page to retrieve. Effectively
3481 identical to creating a non-pages resultset and then calling ->page($page)
3484 If L<rows> attribute is not specified it defaults to 10 rows per page.
3486 When you have a paged resultset, L</count> will only return the number
3487 of rows in the page. To get the total, use the L</pager> and call
3488 C<total_entries> on it.
3498 Specifes the maximum number of rows for direct retrieval or the number of
3499 rows per page if the page attribute or method is used.
3505 =item Value: $offset
3509 Specifies the (zero-based) row number for the first row to be returned, or the
3510 of the first row of the first page if paging is used.
3516 =item Value: \@columns
3520 A arrayref of columns to group by. Can include columns of joined tables.
3522 group_by => [qw/ column1 column2 ... /]
3528 =item Value: $condition
3532 HAVING is a select statement attribute that is applied between GROUP BY and
3533 ORDER BY. It is applied to the after the grouping calculations have been
3536 having => { 'count(employee)' => { '>=', 100 } }
3542 =item Value: (0 | 1)
3546 Set to 1 to group by all columns. If the resultset already has a group_by
3547 attribute, this setting is ignored and an appropriate warning is issued.
3553 Adds to the WHERE clause.
3555 # only return rows WHERE deleted IS NULL for all searches
3556 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
3558 Can be overridden by passing C<< { where => undef } >> as an attribute
3565 Set to 1 to cache search results. This prevents extra SQL queries if you
3566 revisit rows in your ResultSet:
3568 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
3570 while( my $artist = $resultset->next ) {
3574 $rs->first; # without cache, this would issue a query
3576 By default, searches are not cached.
3578 For more examples of using these attributes, see
3579 L<DBIx::Class::Manual::Cookbook>.
3585 =item Value: ( 'update' | 'shared' )
3589 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT