1 package DBIx::Class::ResultSet;
9 use Carp::Clan qw/^DBIx::Class/;
12 use DBIx::Class::ResultSetColumn;
13 use DBIx::Class::ResultSourceHandle;
16 use base qw/DBIx::Class/;
18 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class _source_handle/);
22 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
26 my $users_rs = $schema->resultset('User');
27 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
28 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
32 A ResultSet is an object which stores a set of conditions representing
33 a query. It is the backbone of DBIx::Class (i.e. the really
34 important/useful bit).
36 No SQL is executed on the database when a ResultSet is created, it
37 just stores all the conditions needed to create the query.
39 A basic ResultSet representing the data of an entire table is returned
40 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
41 L<Source|DBIx::Class::Manual::Glossary/Source> name.
43 my $users_rs = $schema->resultset('User');
45 A new ResultSet is returned from calling L</search> on an existing
46 ResultSet. The new one will contain all the conditions of the
47 original, plus any new conditions added in the C<search> call.
49 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
50 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
53 The query that the ResultSet represents is B<only> executed against
54 the database when these methods are called:
55 L</find> L</next> L</all> L</first> L</single> L</count>
59 =head2 Chaining resultsets
61 Let's say you've got a query that needs to be run to return some data
62 to the user. But, you have an authorization system in place that
63 prevents certain users from seeing certain information. So, you want
64 to construct the basic query in one method, but add constraints to it in
69 my $request = $self->get_request; # Get a request object somehow.
70 my $schema = $self->get_schema; # Get the DBIC schema object somehow.
72 my $cd_rs = $schema->resultset('CD')->search({
73 title => $request->param('title'),
74 year => $request->param('year'),
77 $self->apply_security_policy( $cd_rs );
82 sub apply_security_policy {
91 =head3 Resolving conditions and attributes
93 When a resultset is chained from another resultset, conditions and
94 attributes with the same keys need resolving.
96 L</join>, L</prefetch>, L</+select>, L</+as> attributes are merged
97 into the existing ones from the original resultset.
99 The L</where>, L</having> attribute, and any search conditions are
100 merged with an SQL C<AND> to the existing condition from the original
103 All other attributes are overridden by any new ones supplied in the
106 =head2 Multiple queries
108 Since a resultset just defines a query, you can do all sorts of
109 things with it with the same object.
111 # Don't hit the DB yet.
112 my $cd_rs = $schema->resultset('CD')->search({
113 title => 'something',
117 # Each of these hits the DB individually.
118 my $count = $cd_rs->count;
119 my $most_recent = $cd_rs->get_column('date_released')->max();
120 my @records = $cd_rs->all;
122 And it's not just limited to SELECT statements.
128 $cd_rs->create({ artist => 'Fred' });
130 Which is the same as:
132 $schema->resultset('CD')->create({
133 title => 'something',
138 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
142 If a resultset is used in a numeric context it returns the L</count>.
143 However, if it is used in a booleand context it is always true. So if
144 you want to check if a resultset has any results use C<if $rs != 0>.
145 C<if $rs> will always be true.
153 =item Arguments: $source, \%$attrs
155 =item Return Value: $rs
159 The resultset constructor. Takes a source object (usually a
160 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
161 L</ATTRIBUTES> below). Does not perform any queries -- these are
162 executed as needed by the other methods.
164 Generally you won't need to construct a resultset manually. You'll
165 automatically get one from e.g. a L</search> called in scalar context:
167 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
169 IMPORTANT: If called on an object, proxies to new_result instead so
171 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
173 will return a CD object, not a ResultSet.
179 return $class->new_result(@_) if ref $class;
181 my ($source, $attrs) = @_;
182 $source = $source->handle
183 unless $source->isa('DBIx::Class::ResultSourceHandle');
184 $attrs = { %{$attrs||{}} };
186 if ($attrs->{page}) {
187 $attrs->{rows} ||= 10;
190 $attrs->{alias} ||= 'me';
192 # Creation of {} and bless separated to mitigate RH perl bug
193 # see https://bugzilla.redhat.com/show_bug.cgi?id=196836
195 _source_handle => $source,
196 cond => $attrs->{where},
205 $attrs->{result_class} || $source->resolve->result_class
215 =item Arguments: $cond, \%attrs?
217 =item Return Value: $resultset (scalar context), @row_objs (list context)
221 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
222 my $new_rs = $cd_rs->search({ year => 2005 });
224 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
225 # year = 2005 OR year = 2004
227 If you need to pass in additional attributes but no additional condition,
228 call it as C<search(undef, \%attrs)>.
230 # "SELECT name, artistid FROM $artist_table"
231 my @all_artists = $schema->resultset('Artist')->search(undef, {
232 columns => [qw/name artistid/],
235 For a list of attributes that can be passed to C<search>, see
236 L</ATTRIBUTES>. For more examples of using this function, see
237 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
238 documentation for the first argument, see L<SQL::Abstract>.
240 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
246 my $rs = $self->search_rs( @_ );
247 return (wantarray ? $rs->all : $rs);
254 =item Arguments: $cond, \%attrs?
256 =item Return Value: $resultset
260 This method does the same exact thing as search() except it will
261 always return a resultset, even in list context.
268 # Special-case handling for (undef, undef).
269 if ( @_ == 2 && !defined $_[1] && !defined $_[0] ) {
274 $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH';
275 my $our_attrs = { %{$self->{attrs}} };
276 my $having = delete $our_attrs->{having};
277 my $where = delete $our_attrs->{where};
281 my %safe = (alias => 1, cache => 1);
284 (@_ && defined($_[0])) # @_ == () or (undef)
286 (keys %$attrs # empty attrs or only 'safe' attrs
287 && List::Util::first { !$safe{$_} } keys %$attrs)
289 # no search, effectively just a clone
290 $rows = $self->get_cache;
293 my $new_attrs = { %{$our_attrs}, %{$attrs} };
295 # merge new attrs into inherited
296 foreach my $key (qw/join prefetch +select +as bind/) {
297 next unless exists $attrs->{$key};
298 $new_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key});
303 (@_ == 1 || ref $_[0] eq "HASH")
305 (ref $_[0] eq 'HASH')
307 (keys %{ $_[0] } > 0)
315 ? $self->throw_exception("Odd number of arguments to search")
322 if (defined $where) {
323 $new_attrs->{where} = (
324 defined $new_attrs->{where}
327 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
328 } $where, $new_attrs->{where}
335 $new_attrs->{where} = (
336 defined $new_attrs->{where}
339 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
340 } $cond, $new_attrs->{where}
346 if (defined $having) {
347 $new_attrs->{having} = (
348 defined $new_attrs->{having}
351 ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_
352 } $having, $new_attrs->{having}
358 my $rs = (ref $self)->new($self->result_source, $new_attrs);
360 $rs->set_cache($rows);
365 =head2 search_literal
369 =item Arguments: $sql_fragment, @bind_values
371 =item Return Value: $resultset (scalar context), @row_objs (list context)
375 my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/);
376 my $newrs = $artist_rs->search_literal('name = ?', 'Metallica');
378 Pass a literal chunk of SQL to be added to the conditional part of the
381 CAVEAT: C<search_literal> is provided for Class::DBI compatibility and should
382 only be used in that context. C<search_literal> is a convenience method.
383 It is equivalent to calling $schema->search(\[]), but if you want to ensure
384 columns are bound correctly, use C<search>.
386 Example of how to use C<search> instead of C<search_literal>
388 my @cds = $cd_rs->search_literal('cdid = ? AND (artist = ? OR artist = ?)', (2, 1, 2));
389 my @cds = $cd_rs->search(\[ 'cdid = ? AND (artist = ? OR artist = ?)', [ 'cdid', 2 ], [ 'artist', 1 ], [ 'artist', 2 ] ]);
392 See L<DBIx::Class::Manual::Cookbook/Searching> and
393 L<DBIx::Class::Manual::FAQ/Searching> for searching techniques that do not
394 require C<search_literal>.
399 my ($self, $sql, @bind) = @_;
401 if ( @bind && ref($bind[-1]) eq 'HASH' ) {
404 return $self->search(\[ $sql, map [ __DUMMY__ => $_ ], @bind ], ($attr || () ));
411 =item Arguments: @values | \%cols, \%attrs?
413 =item Return Value: $row_object | undef
417 Finds a row based on its primary key or unique constraint. For example, to find
418 a row by its primary key:
420 my $cd = $schema->resultset('CD')->find(5);
422 You can also find a row by a specific unique constraint using the C<key>
423 attribute. For example:
425 my $cd = $schema->resultset('CD')->find('Massive Attack', 'Mezzanine', {
426 key => 'cd_artist_title'
429 Additionally, you can specify the columns explicitly by name:
431 my $cd = $schema->resultset('CD')->find(
433 artist => 'Massive Attack',
434 title => 'Mezzanine',
436 { key => 'cd_artist_title' }
439 If the C<key> is specified as C<primary>, it searches only on the primary key.
441 If no C<key> is specified, it searches on all unique constraints defined on the
442 source for which column data is provided, including the primary key.
444 If your table does not have a primary key, you B<must> provide a value for the
445 C<key> attribute matching one of the unique constraints on the source.
447 In addition to C<key>, L</find> recognizes and applies standard
448 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
450 Note: If your query does not return only one row, a warning is generated:
452 Query returned more than one row
454 See also L</find_or_create> and L</update_or_create>. For information on how to
455 declare unique constraints, see
456 L<DBIx::Class::ResultSource/add_unique_constraint>.
462 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
464 # Default to the primary key, but allow a specific key
465 my @cols = exists $attrs->{key}
466 ? $self->result_source->unique_constraint_columns($attrs->{key})
467 : $self->result_source->primary_columns;
468 $self->throw_exception(
469 "Can't find unless a primary key is defined or unique constraint is specified"
472 # Parse out a hashref from input
474 if (ref $_[0] eq 'HASH') {
475 $input_query = { %{$_[0]} };
477 elsif (@_ == @cols) {
479 @{$input_query}{@cols} = @_;
482 # Compatibility: Allow e.g. find(id => $value)
483 carp "Find by key => value deprecated; please use a hashref instead";
487 my (%related, $info);
489 KEY: foreach my $key (keys %$input_query) {
490 if (ref($input_query->{$key})
491 && ($info = $self->result_source->relationship_info($key))) {
492 my $val = delete $input_query->{$key};
493 next KEY if (ref($val) eq 'ARRAY'); # has_many for multi_create
494 my $rel_q = $self->result_source->_resolve_condition(
495 $info->{cond}, $val, $key
497 die "Can't handle OR join condition in find" if ref($rel_q) eq 'ARRAY';
498 @related{keys %$rel_q} = values %$rel_q;
501 if (my @keys = keys %related) {
502 @{$input_query}{@keys} = values %related;
506 # Build the final query: Default to the disjunction of the unique queries,
507 # but allow the input query in case the ResultSet defines the query or the
508 # user is abusing find
509 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
511 if (exists $attrs->{key}) {
512 my @unique_cols = $self->result_source->unique_constraint_columns($attrs->{key});
513 my $unique_query = $self->_build_unique_query($input_query, \@unique_cols);
514 $query = $self->_add_alias($unique_query, $alias);
516 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
517 # This means that we got here after a merger of relationship conditions
518 # in ::Relationship::Base::search_related (the row method), and furthermore
519 # the relationship is of the 'single' type. This means that the condition
520 # provided by the relationship (already attached to $self) is sufficient,
521 # as there can be only one row in the databse that would satisfy the
525 my @unique_queries = $self->_unique_queries($input_query, $attrs);
526 $query = @unique_queries
527 ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
528 : $self->_add_alias($input_query, $alias);
532 my $rs = $self->search ($query, $attrs);
533 if (keys %{$rs->_resolved_attrs->{collapse}}) {
535 carp "Query returned more than one row" if $rs->next;
545 # Add the specified alias to the specified query hash. A copy is made so the
546 # original query is not modified.
549 my ($self, $query, $alias) = @_;
551 my %aliased = %$query;
552 foreach my $col (grep { ! m/\./ } keys %aliased) {
553 $aliased{"$alias.$col"} = delete $aliased{$col};
561 # Build a list of queries which satisfy unique constraints.
563 sub _unique_queries {
564 my ($self, $query, $attrs) = @_;
566 my @constraint_names = exists $attrs->{key}
568 : $self->result_source->unique_constraint_names;
570 my $where = $self->_collapse_cond($self->{attrs}{where} || {});
571 my $num_where = scalar keys %$where;
574 foreach my $name (@constraint_names) {
575 my @unique_cols = $self->result_source->unique_constraint_columns($name);
576 my $unique_query = $self->_build_unique_query($query, \@unique_cols);
578 my $num_cols = scalar @unique_cols;
579 my $num_query = scalar keys %$unique_query;
581 my $total = $num_query + $num_where;
582 if ($num_query && ($num_query == $num_cols || $total == $num_cols)) {
583 # The query is either unique on its own or is unique in combination with
584 # the existing where clause
585 push @unique_queries, $unique_query;
589 return @unique_queries;
592 # _build_unique_query
594 # Constrain the specified query hash based on the specified column names.
596 sub _build_unique_query {
597 my ($self, $query, $unique_cols) = @_;
600 map { $_ => $query->{$_} }
601 grep { exists $query->{$_} }
606 =head2 search_related
610 =item Arguments: $rel, $cond, \%attrs?
612 =item Return Value: $new_resultset
616 $new_rs = $cd_rs->search_related('artist', {
620 Searches the specified relationship, optionally specifying a condition and
621 attributes for matching records. See L</ATTRIBUTES> for more information.
626 return shift->related_resultset(shift)->search(@_);
629 =head2 search_related_rs
631 This method works exactly the same as search_related, except that
632 it guarantees a restultset, even in list context.
636 sub search_related_rs {
637 return shift->related_resultset(shift)->search_rs(@_);
644 =item Arguments: none
646 =item Return Value: $cursor
650 Returns a storage-driven cursor to the given resultset. See
651 L<DBIx::Class::Cursor> for more information.
658 my $attrs = $self->_resolved_attrs_copy;
660 return $self->{cursor}
661 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
662 $attrs->{where},$attrs);
669 =item Arguments: $cond?
671 =item Return Value: $row_object?
675 my $cd = $schema->resultset('CD')->single({ year => 2001 });
677 Inflates the first result without creating a cursor if the resultset has
678 any records in it; if not returns nothing. Used by L</find> as a lean version of
681 While this method can take an optional search condition (just like L</search>)
682 being a fast-code-path it does not recognize search attributes. If you need to
683 add extra joins or similar, call L</search> and then chain-call L</single> on the
684 L<DBIx::Class::ResultSet> returned.
690 As of 0.08100, this method enforces the assumption that the preceeding
691 query returns only one row. If more than one row is returned, you will receive
694 Query returned more than one row
696 In this case, you should be using L</next> or L</find> instead, or if you really
697 know what you are doing, use the L</rows> attribute to explicitly limit the size
700 This method will also throw an exception if it is called on a resultset prefetching
701 has_many, as such a prefetch implies fetching multiple rows from the database in
702 order to assemble the resulting object.
709 my ($self, $where) = @_;
711 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
714 my $attrs = $self->_resolved_attrs_copy;
716 if (keys %{$attrs->{collapse}}) {
717 $self->throw_exception(
718 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
723 if (defined $attrs->{where}) {
726 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
727 $where, delete $attrs->{where} ]
730 $attrs->{where} = $where;
734 # XXX: Disabled since it doesn't infer uniqueness in all cases
735 # unless ($self->_is_unique_query($attrs->{where})) {
736 # carp "Query not guaranteed to return a single row"
737 # . "; please declare your unique constraints or use search instead";
740 my @data = $self->result_source->storage->select_single(
741 $attrs->{from}, $attrs->{select},
742 $attrs->{where}, $attrs
745 return (@data ? ($self->_construct_object(@data))[0] : undef);
751 # Try to determine if the specified query is guaranteed to be unique, based on
752 # the declared unique constraints.
754 sub _is_unique_query {
755 my ($self, $query) = @_;
757 my $collapsed = $self->_collapse_query($query);
758 my $alias = $self->{attrs}{alias};
760 foreach my $name ($self->result_source->unique_constraint_names) {
761 my @unique_cols = map {
763 } $self->result_source->unique_constraint_columns($name);
765 # Count the values for each unique column
766 my %seen = map { $_ => 0 } @unique_cols;
768 foreach my $key (keys %$collapsed) {
769 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
770 next unless exists $seen{$aliased}; # Additional constraints are okay
771 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
774 # If we get 0 or more than 1 value for a column, it's not necessarily unique
775 return 1 unless grep { $_ != 1 } values %seen;
783 # Recursively collapse the query, accumulating values for each column.
785 sub _collapse_query {
786 my ($self, $query, $collapsed) = @_;
790 if (ref $query eq 'ARRAY') {
791 foreach my $subquery (@$query) {
792 next unless ref $subquery; # -or
793 $collapsed = $self->_collapse_query($subquery, $collapsed);
796 elsif (ref $query eq 'HASH') {
797 if (keys %$query and (keys %$query)[0] eq '-and') {
798 foreach my $subquery (@{$query->{-and}}) {
799 $collapsed = $self->_collapse_query($subquery, $collapsed);
803 foreach my $col (keys %$query) {
804 my $value = $query->{$col};
805 $collapsed->{$col}{$value}++;
817 =item Arguments: $cond?
819 =item Return Value: $resultsetcolumn
823 my $max_length = $rs->get_column('length')->max;
825 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
830 my ($self, $column) = @_;
831 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
839 =item Arguments: $cond, \%attrs?
841 =item Return Value: $resultset (scalar context), @row_objs (list context)
845 # WHERE title LIKE '%blue%'
846 $cd_rs = $rs->search_like({ title => '%blue%'});
848 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
849 that this is simply a convenience method retained for ex Class::DBI users.
850 You most likely want to use L</search> with specific operators.
852 For more information, see L<DBIx::Class::Manual::Cookbook>.
854 This method is deprecated and will be removed in 0.09. Use L</search()>
855 instead. An example conversion is:
857 ->search_like({ foo => 'bar' });
861 ->search({ foo => { like => 'bar' } });
868 'search_like() is deprecated and will be removed in DBIC version 0.09.'
869 .' Instead use ->search({ x => { -like => "y%" } })'
870 .' (note the outer pair of {}s - they are important!)'
872 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
873 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
874 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
875 return $class->search($query, { %$attrs });
882 =item Arguments: $first, $last
884 =item Return Value: $resultset (scalar context), @row_objs (list context)
888 Returns a resultset or object list representing a subset of elements from the
889 resultset slice is called on. Indexes are from 0, i.e., to get the first
892 my ($one, $two, $three) = $rs->slice(0, 2);
897 my ($self, $min, $max) = @_;
898 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
899 $attrs->{offset} = $self->{attrs}{offset} || 0;
900 $attrs->{offset} += $min;
901 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
902 return $self->search(undef(), $attrs);
903 #my $slice = (ref $self)->new($self->result_source, $attrs);
904 #return (wantarray ? $slice->all : $slice);
911 =item Arguments: none
913 =item Return Value: $result?
917 Returns the next element in the resultset (C<undef> is there is none).
919 Can be used to efficiently iterate over records in the resultset:
921 my $rs = $schema->resultset('CD')->search;
922 while (my $cd = $rs->next) {
926 Note that you need to store the resultset object, and call C<next> on it.
927 Calling C<< resultset('Table')->next >> repeatedly will always return the
928 first record from the resultset.
934 if (my $cache = $self->get_cache) {
935 $self->{all_cache_position} ||= 0;
936 return $cache->[$self->{all_cache_position}++];
938 if ($self->{attrs}{cache}) {
939 $self->{all_cache_position} = 1;
940 return ($self->all)[0];
942 if ($self->{stashed_objects}) {
943 my $obj = shift(@{$self->{stashed_objects}});
944 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
948 exists $self->{stashed_row}
949 ? @{delete $self->{stashed_row}}
950 : $self->cursor->next
952 return undef unless (@row);
953 my ($row, @more) = $self->_construct_object(@row);
954 $self->{stashed_objects} = \@more if @more;
958 sub _construct_object {
959 my ($self, @row) = @_;
960 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row);
961 my @new = $self->result_class->inflate_result($self->result_source, @$info);
962 @new = $self->{_attrs}{record_filter}->(@new)
963 if exists $self->{_attrs}{record_filter};
967 sub _collapse_result {
968 my ($self, $as_proto, $row) = @_;
972 # 'foo' => [ undef, 'foo' ]
973 # 'foo.bar' => [ 'foo', 'bar' ]
974 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
976 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
978 my %collapse = %{$self->{_attrs}{collapse}||{}};
982 # if we're doing collapsing (has_many prefetch) we need to grab records
983 # until the PK changes, so fill @pri_index. if not, we leave it empty so
984 # we know we don't have to bother.
986 # the reason for not using the collapse stuff directly is because if you
987 # had for e.g. two artists in a row with no cds, the collapse info for
988 # both would be NULL (undef) so you'd lose the second artist
990 # store just the index so we can check the array positions from the row
991 # without having to contruct the full hash
993 if (keys %collapse) {
994 my %pri = map { ($_ => 1) } $self->result_source->primary_columns;
995 foreach my $i (0 .. $#construct_as) {
996 next if defined($construct_as[$i][0]); # only self table
997 if (delete $pri{$construct_as[$i][1]}) {
998 push(@pri_index, $i);
1000 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
1004 # no need to do an if, it'll be empty if @pri_index is empty anyway
1006 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
1010 do { # no need to check anything at the front, we always want the first row
1014 foreach my $this_as (@construct_as) {
1015 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
1018 push(@const_rows, \%const);
1020 } until ( # no pri_index => no collapse => drop straight out
1023 do { # get another row, stash it, drop out if different PK
1025 @copy = $self->cursor->next;
1026 $self->{stashed_row} = \@copy;
1028 # last thing in do block, counts as true if anything doesn't match
1030 # check xor defined first for NULL vs. NOT NULL then if one is
1031 # defined the other must be so check string equality
1034 (defined $pri_vals{$_} ^ defined $copy[$_])
1035 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
1040 my $alias = $self->{attrs}{alias};
1047 foreach my $const (@const_rows) {
1048 scalar @const_keys or do {
1049 @const_keys = sort { length($a) <=> length($b) } keys %$const;
1051 foreach my $key (@const_keys) {
1054 my @parts = split(/\./, $key);
1056 my $data = $const->{$key};
1057 foreach my $p (@parts) {
1058 $target = $target->[1]->{$p} ||= [];
1060 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
1061 # collapsing at this point and on final part
1062 my $pos = $collapse_pos{$cur};
1063 CK: foreach my $ck (@ckey) {
1064 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
1065 $collapse_pos{$cur} = $data;
1066 delete @collapse_pos{ # clear all positioning for sub-entries
1067 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
1074 if (exists $collapse{$cur}) {
1075 $target = $target->[-1];
1078 $target->[0] = $data;
1080 $info->[0] = $const->{$key};
1088 =head2 result_source
1092 =item Arguments: $result_source?
1094 =item Return Value: $result_source
1098 An accessor for the primary ResultSource object from which this ResultSet
1105 =item Arguments: $result_class?
1107 =item Return Value: $result_class
1111 An accessor for the class to use when creating row objects. Defaults to
1112 C<< result_source->result_class >> - which in most cases is the name of the
1113 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1115 Note that changing the result_class will also remove any components
1116 that were originally loaded in the source class via
1117 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1118 in the original source class will not run.
1123 my ($self, $result_class) = @_;
1124 if ($result_class) {
1125 $self->ensure_class_loaded($result_class);
1126 $self->_result_class($result_class);
1128 $self->_result_class;
1135 =item Arguments: $cond, \%attrs??
1137 =item Return Value: $count
1141 Performs an SQL C<COUNT> with the same query as the resultset was built
1142 with to find the number of elements. Passing arguments is equivalent to
1143 C<< $rs->search ($cond, \%attrs)->count >>
1149 return $self->search(@_)->count if @_ and defined $_[0];
1150 return scalar @{ $self->get_cache } if $self->get_cache;
1152 my $attrs = $self->_resolved_attrs_copy;
1154 # this is a little optimization - it is faster to do the limit
1155 # adjustments in software, instead of a subquery
1156 my $rows = delete $attrs->{rows};
1157 my $offset = delete $attrs->{offset};
1160 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1161 $crs = $self->_count_subq_rs ($attrs);
1164 $crs = $self->_count_rs ($attrs);
1166 my $count = $crs->next;
1168 $count -= $offset if $offset;
1169 $count = $rows if $rows and $rows < $count;
1170 $count = 0 if ($count < 0);
1179 =item Arguments: $cond, \%attrs??
1181 =item Return Value: $count_rs
1185 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1186 This can be very handy for subqueries:
1188 ->search( { amount => $some_rs->count_rs->as_query } )
1190 As with regular resultsets the SQL query will be executed only after
1191 the resultset is accessed via L</next> or L</all>. That would return
1192 the same single value obtainable via L</count>.
1198 return $self->search(@_)->count_rs if @_;
1200 # this may look like a lack of abstraction (count() does about the same)
1201 # but in fact an _rs *must* use a subquery for the limits, as the
1202 # software based limiting can not be ported if this $rs is to be used
1203 # in a subquery itself (i.e. ->as_query)
1204 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1205 return $self->_count_subq_rs;
1208 return $self->_count_rs;
1213 # returns a ResultSetColumn object tied to the count query
1216 my ($self, $attrs) = @_;
1218 my $rsrc = $self->result_source;
1219 $attrs ||= $self->_resolved_attrs;
1221 my $tmp_attrs = { %$attrs };
1223 # take off any limits, record_filter is cdbi, and no point of ordering a count
1224 delete $tmp_attrs->{$_} for (qw/select as rows offset order_by record_filter/);
1226 # overwrite the selector (supplied by the storage)
1227 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $tmp_attrs);
1228 $tmp_attrs->{as} = 'count';
1230 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1236 # same as above but uses a subquery
1238 sub _count_subq_rs {
1239 my ($self, $attrs) = @_;
1241 my $rsrc = $self->result_source;
1242 $attrs ||= $self->_resolved_attrs_copy;
1244 my $sub_attrs = { %$attrs };
1246 # these can not go in the subquery, and there is no point of ordering it
1247 delete $sub_attrs->{$_} for qw/collapse select as order_by/;
1249 # if we prefetch, we group_by primary keys only as this is what we would get out of the rs via ->next/->all
1250 # clobber old group_by regardless
1251 if ( keys %{$attrs->{collapse}} ) {
1252 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } ($rsrc->primary_columns) ]
1255 $sub_attrs->{select} = $rsrc->storage->_subq_count_select ($rsrc, $sub_attrs);
1258 count_subq => $rsrc->resultset_class->new ($rsrc, $sub_attrs )->as_query
1261 # the subquery replaces this
1262 delete $attrs->{$_} for qw/where bind collapse group_by having having_bind rows offset/;
1264 return $self->_count_rs ($attrs);
1272 =head2 count_literal
1276 =item Arguments: $sql_fragment, @bind_values
1278 =item Return Value: $count
1282 Counts the results in a literal query. Equivalent to calling L</search_literal>
1283 with the passed arguments, then L</count>.
1287 sub count_literal { shift->search_literal(@_)->count; }
1293 =item Arguments: none
1295 =item Return Value: @objects
1299 Returns all elements in the resultset. Called implicitly if the resultset
1300 is returned in list context.
1307 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1310 return @{ $self->get_cache } if $self->get_cache;
1314 # TODO: don't call resolve here
1315 if (keys %{$self->_resolved_attrs->{collapse}}) {
1316 # if ($self->{attrs}{prefetch}) {
1317 # Using $self->cursor->all is really just an optimisation.
1318 # If we're collapsing has_many prefetches it probably makes
1319 # very little difference, and this is cleaner than hacking
1320 # _construct_object to survive the approach
1321 my @row = $self->cursor->next;
1323 push(@obj, $self->_construct_object(@row));
1324 @row = (exists $self->{stashed_row}
1325 ? @{delete $self->{stashed_row}}
1326 : $self->cursor->next);
1329 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1332 $self->set_cache(\@obj) if $self->{attrs}{cache};
1340 =item Arguments: none
1342 =item Return Value: $self
1346 Resets the resultset's cursor, so you can iterate through the elements again.
1352 delete $self->{_attrs} if exists $self->{_attrs};
1353 $self->{all_cache_position} = 0;
1354 $self->cursor->reset;
1362 =item Arguments: none
1364 =item Return Value: $object?
1368 Resets the resultset and returns an object for the first result (if the
1369 resultset returns anything).
1374 return $_[0]->reset->next;
1380 # Determines whether and what type of subquery is required for the $rs operation.
1381 # If grouping is necessary either supplies its own, or verifies the current one
1382 # After all is done delegates to the proper storage method.
1384 sub _rs_update_delete {
1385 my ($self, $op, $values) = @_;
1387 my $rsrc = $self->result_source;
1389 my $needs_group_by_subq = $self->_has_resolved_attr (qw/collapse group_by -join/);
1390 my $needs_subq = $self->_has_resolved_attr (qw/row offset/);
1392 if ($needs_group_by_subq or $needs_subq) {
1394 # make a new $rs selecting only the PKs (that's all we really need)
1395 my $attrs = $self->_resolved_attrs_copy;
1397 delete $attrs->{$_} for qw/collapse select as/;
1398 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->primary_columns) ];
1400 if ($needs_group_by_subq) {
1401 # make sure no group_by was supplied, or if there is one - make sure it matches
1402 # the columns compiled above perfectly. Anything else can not be sanely executed
1403 # on most databases so croak right then and there
1405 if (my $g = $attrs->{group_by}) {
1406 my @current_group_by = map
1407 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1408 (ref $g eq 'ARRAY' ? @$g : $g );
1411 join ("\x00", sort @current_group_by)
1413 join ("\x00", sort @{$attrs->{columns}} )
1415 $self->throw_exception (
1416 "You have just attempted a $op operation on a resultset which does group_by"
1417 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1418 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1419 . ' kind of queries. Please retry the operation with a modified group_by or'
1420 . ' without using one at all.'
1425 $attrs->{group_by} = $attrs->{columns};
1429 my $subrs = (ref $self)->new($rsrc, $attrs);
1431 return $self->result_source->storage->_subq_update_delete($subrs, $op, $values);
1434 return $rsrc->storage->$op(
1436 $op eq 'update' ? $values : (),
1437 $self->_cond_for_update_delete,
1443 # _cond_for_update_delete
1445 # update/delete require the condition to be modified to handle
1446 # the differing SQL syntax available. This transforms the $self->{cond}
1447 # appropriately, returning the new condition.
1449 sub _cond_for_update_delete {
1450 my ($self, $full_cond) = @_;
1453 $full_cond ||= $self->{cond};
1454 # No-op. No condition, we're updating/deleting everything
1455 return $cond unless ref $full_cond;
1457 if (ref $full_cond eq 'ARRAY') {
1461 foreach my $key (keys %{$_}) {
1463 $hash{$1} = $_->{$key};
1469 elsif (ref $full_cond eq 'HASH') {
1470 if ((keys %{$full_cond})[0] eq '-and') {
1472 my @cond = @{$full_cond->{-and}};
1473 for (my $i = 0; $i < @cond; $i++) {
1474 my $entry = $cond[$i];
1476 if (ref $entry eq 'HASH') {
1477 $hash = $self->_cond_for_update_delete($entry);
1480 $entry =~ /([^.]+)$/;
1481 $hash->{$1} = $cond[++$i];
1483 push @{$cond->{-and}}, $hash;
1487 foreach my $key (keys %{$full_cond}) {
1489 $cond->{$1} = $full_cond->{$key};
1494 $self->throw_exception("Can't update/delete on resultset with condition unless hash or array");
1505 =item Arguments: \%values
1507 =item Return Value: $storage_rv
1511 Sets the specified columns in the resultset to the supplied values in a
1512 single query. Return value will be true if the update succeeded or false
1513 if no records were updated; exact type of success value is storage-dependent.
1518 my ($self, $values) = @_;
1519 $self->throw_exception('Values for update must be a hash')
1520 unless ref $values eq 'HASH';
1522 return $self->_rs_update_delete ('update', $values);
1529 =item Arguments: \%values
1531 =item Return Value: 1
1535 Fetches all objects and updates them one at a time. Note that C<update_all>
1536 will run DBIC cascade triggers, while L</update> will not.
1541 my ($self, $values) = @_;
1542 $self->throw_exception('Values for update_all must be a hash')
1543 unless ref $values eq 'HASH';
1544 foreach my $obj ($self->all) {
1545 $obj->set_columns($values)->update;
1554 =item Arguments: none
1556 =item Return Value: $storage_rv
1560 Deletes the contents of the resultset from its result source. Note that this
1561 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1562 to run. See also L<DBIx::Class::Row/delete>.
1564 Return value will be the amount of rows deleted; exact type of return value
1565 is storage-dependent.
1571 $self->throw_exception('delete does not accept any arguments')
1574 return $self->_rs_update_delete ('delete');
1581 =item Arguments: none
1583 =item Return Value: 1
1587 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1588 will run DBIC cascade triggers, while L</delete> will not.
1594 $self->throw_exception('delete_all does not accept any arguments')
1597 $_->delete for $self->all;
1605 =item Arguments: \@data;
1609 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1610 For the arrayref of hashrefs style each hashref should be a structure suitable
1611 forsubmitting to a $resultset->create(...) method.
1613 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1614 to insert the data, as this is a faster method.
1616 Otherwise, each set of data is inserted into the database using
1617 L<DBIx::Class::ResultSet/create>, and the resulting objects are
1618 accumulated into an array. The array itself, or an array reference
1619 is returned depending on scalar or list context.
1621 Example: Assuming an Artist Class that has many CDs Classes relating:
1623 my $Artist_rs = $schema->resultset("Artist");
1625 ## Void Context Example
1626 $Artist_rs->populate([
1627 { artistid => 4, name => 'Manufactured Crap', cds => [
1628 { title => 'My First CD', year => 2006 },
1629 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1632 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1633 { title => 'My parents sold me to a record company' ,year => 2005 },
1634 { title => 'Why Am I So Ugly?', year => 2006 },
1635 { title => 'I Got Surgery and am now Popular', year => 2007 }
1640 ## Array Context Example
1641 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1642 { name => "Artist One"},
1643 { name => "Artist Two"},
1644 { name => "Artist Three", cds=> [
1645 { title => "First CD", year => 2007},
1646 { title => "Second CD", year => 2008},
1650 print $ArtistOne->name; ## response is 'Artist One'
1651 print $ArtistThree->cds->count ## reponse is '2'
1653 For the arrayref of arrayrefs style, the first element should be a list of the
1654 fieldsnames to which the remaining elements are rows being inserted. For
1657 $Arstist_rs->populate([
1658 [qw/artistid name/],
1659 [100, 'A Formally Unknown Singer'],
1660 [101, 'A singer that jumped the shark two albums ago'],
1661 [102, 'An actually cool singer.'],
1664 Please note an important effect on your data when choosing between void and
1665 wantarray context. Since void context goes straight to C<insert_bulk> in
1666 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
1667 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
1668 create primary keys for you, you will find that your PKs are empty. In this
1669 case you will have to use the wantarray context in order to create those
1675 my $self = shift @_;
1676 my $data = ref $_[0][0] eq 'HASH'
1677 ? $_[0] : ref $_[0][0] eq 'ARRAY' ? $self->_normalize_populate_args($_[0]) :
1678 $self->throw_exception('Populate expects an arrayref of hashes or arrayref of arrayrefs');
1680 if(defined wantarray) {
1682 foreach my $item (@$data) {
1683 push(@created, $self->create($item));
1685 return wantarray ? @created : \@created;
1687 my ($first, @rest) = @$data;
1689 my @names = grep {!ref $first->{$_}} keys %$first;
1690 my @rels = grep { $self->result_source->has_relationship($_) } keys %$first;
1691 my @pks = $self->result_source->primary_columns;
1693 ## do the belongs_to relationships
1694 foreach my $index (0..$#$data) {
1696 # delegate to create() for any dataset without primary keys with specified relationships
1697 if (grep { !defined $data->[$index]->{$_} } @pks ) {
1699 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
1700 my @ret = $self->populate($data);
1706 foreach my $rel (@rels) {
1707 next unless ref $data->[$index]->{$rel} eq "HASH";
1708 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1709 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1710 my $related = $result->result_source->_resolve_condition(
1711 $result->result_source->relationship_info($reverse)->{cond},
1716 delete $data->[$index]->{$rel};
1717 $data->[$index] = {%{$data->[$index]}, %$related};
1719 push @names, keys %$related if $index == 0;
1723 ## do bulk insert on current row
1724 my @values = map { [ @$_{@names} ] } @$data;
1726 $self->result_source->storage->insert_bulk(
1727 $self->result_source,
1732 ## do the has_many relationships
1733 foreach my $item (@$data) {
1735 foreach my $rel (@rels) {
1736 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1738 my $parent = $self->find(map {{$_=>$item->{$_}} } @pks)
1739 || $self->throw_exception('Cannot find the relating object.');
1741 my $child = $parent->$rel;
1743 my $related = $child->result_source->_resolve_condition(
1744 $parent->result_source->relationship_info($rel)->{cond},
1749 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1750 my @populate = map { {%$_, %$related} } @rows_to_add;
1752 $child->populate( \@populate );
1758 =head2 _normalize_populate_args ($args)
1760 Private method used by L</populate> to normalize its incoming arguments. Factored
1761 out in case you want to subclass and accept new argument structures to the
1762 L</populate> method.
1766 sub _normalize_populate_args {
1767 my ($self, $data) = @_;
1768 my @names = @{shift(@$data)};
1769 my @results_to_create;
1770 foreach my $datum (@$data) {
1771 my %result_to_create;
1772 foreach my $index (0..$#names) {
1773 $result_to_create{$names[$index]} = $$datum[$index];
1775 push @results_to_create, \%result_to_create;
1777 return \@results_to_create;
1784 =item Arguments: none
1786 =item Return Value: $pager
1790 Return Value a L<Data::Page> object for the current resultset. Only makes
1791 sense for queries with a C<page> attribute.
1793 To get the full count of entries for a paged resultset, call
1794 C<total_entries> on the L<Data::Page> object.
1801 return $self->{pager} if $self->{pager};
1803 my $attrs = $self->{attrs};
1804 $self->throw_exception("Can't create pager for non-paged rs")
1805 unless $self->{attrs}{page};
1806 $attrs->{rows} ||= 10;
1808 # throw away the paging flags and re-run the count (possibly
1809 # with a subselect) to get the real total count
1810 my $count_attrs = { %$attrs };
1811 delete $count_attrs->{$_} for qw/rows offset page pager/;
1812 my $total_count = (ref $self)->new($self->result_source, $count_attrs)->count;
1814 return $self->{pager} = Data::Page->new(
1817 $self->{attrs}{page}
1825 =item Arguments: $page_number
1827 =item Return Value: $rs
1831 Returns a resultset for the $page_number page of the resultset on which page
1832 is called, where each page contains a number of rows equal to the 'rows'
1833 attribute set on the resultset (10 by default).
1838 my ($self, $page) = @_;
1839 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1846 =item Arguments: \%vals
1848 =item Return Value: $rowobject
1852 Creates a new row object in the resultset's result class and returns
1853 it. The row is not inserted into the database at this point, call
1854 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
1855 will tell you whether the row object has been inserted or not.
1857 Passes the hashref of input on to L<DBIx::Class::Row/new>.
1862 my ($self, $values) = @_;
1863 $self->throw_exception( "new_result needs a hash" )
1864 unless (ref $values eq 'HASH');
1867 my $alias = $self->{attrs}{alias};
1870 defined $self->{cond}
1871 && $self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION
1873 %new = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
1874 $new{-from_resultset} = [ keys %new ] if keys %new;
1876 $self->throw_exception(
1877 "Can't abstract implicit construct, condition not a hash"
1878 ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
1880 my $collapsed_cond = (
1882 ? $self->_collapse_cond($self->{cond})
1886 # precendence must be given to passed values over values inherited from
1887 # the cond, so the order here is important.
1888 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
1889 while( my($col,$value) = each %implied ){
1890 if(ref($value) eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '='){
1891 $new{$col} = $value->{'='};
1894 $new{$col} = $value if $self->_is_deterministic_value($value);
1900 %{ $self->_remove_alias($values, $alias) },
1901 -source_handle => $self->_source_handle,
1902 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
1905 return $self->result_class->new(\%new);
1908 # _is_deterministic_value
1910 # Make an effor to strip non-deterministic values from the condition,
1911 # to make sure new_result chokes less
1913 sub _is_deterministic_value {
1916 my $ref_type = ref $value;
1917 return 1 if $ref_type eq '' || $ref_type eq 'SCALAR';
1918 return 1 if Scalar::Util::blessed($value);
1922 # _has_resolved_attr
1924 # determines if the resultset defines at least one
1925 # of the attributes supplied
1927 # used to determine if a subquery is neccessary
1929 sub _has_resolved_attr {
1930 my ($self, @attr_names) = @_;
1932 my $attrs = $self->_resolved_attrs;
1936 for my $n (@attr_names) {
1937 ++$join_check_req if $n eq '-join';
1939 my $attr = $attrs->{$n};
1941 next if not defined $attr;
1943 if (ref $attr eq 'HASH') {
1944 return 1 if keys %$attr;
1946 elsif (ref $attr eq 'ARRAY') {
1954 # a resolved join is expressed as a multi-level from
1958 ref $attrs->{from} eq 'ARRAY'
1960 @{$attrs->{from}} > 1
1968 # Recursively collapse the condition.
1970 sub _collapse_cond {
1971 my ($self, $cond, $collapsed) = @_;
1975 if (ref $cond eq 'ARRAY') {
1976 foreach my $subcond (@$cond) {
1977 next unless ref $subcond; # -or
1978 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1981 elsif (ref $cond eq 'HASH') {
1982 if (keys %$cond and (keys %$cond)[0] eq '-and') {
1983 foreach my $subcond (@{$cond->{-and}}) {
1984 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1988 foreach my $col (keys %$cond) {
1989 my $value = $cond->{$col};
1990 $collapsed->{$col} = $value;
2000 # Remove the specified alias from the specified query hash. A copy is made so
2001 # the original query is not modified.
2004 my ($self, $query, $alias) = @_;
2006 my %orig = %{ $query || {} };
2009 foreach my $key (keys %orig) {
2011 $unaliased{$key} = $orig{$key};
2014 $unaliased{$1} = $orig{$key}
2015 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2021 =head2 as_query (EXPERIMENTAL)
2025 =item Arguments: none
2027 =item Return Value: \[ $sql, @bind ]
2031 Returns the SQL query and bind vars associated with the invocant.
2033 This is generally used as the RHS for a subquery.
2035 B<NOTE>: This feature is still experimental.
2042 my $attrs = $self->_resolved_attrs_copy;
2047 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2048 # $sql also has no wrapping parenthesis in list ctx
2050 my $sqlbind = $self->result_source->storage
2051 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2060 =item Arguments: \%vals, \%attrs?
2062 =item Return Value: $rowobject
2066 my $artist = $schema->resultset('Artist')->find_or_new(
2067 { artist => 'fred' }, { key => 'artists' });
2069 $cd->cd_to_producer->find_or_new({ producer => $producer },
2070 { key => 'primary });
2072 Find an existing record from this resultset, based on its primary
2073 key, or a unique constraint. If none exists, instantiate a new result
2074 object and return it. The object will not be saved into your storage
2075 until you call L<DBIx::Class::Row/insert> on it.
2077 You most likely want this method when looking for existing rows using
2078 a unique constraint that is not the primary key, or looking for
2081 If you want objects to be saved immediately, use L</find_or_create> instead.
2083 B<Note>: C<find_or_new> is probably not what you want when creating a
2084 new row in a table that uses primary keys supplied by the
2085 database. Passing in a primary key column with a value of I<undef>
2086 will cause L</find> to attempt to search for a row with a value of
2093 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2094 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2095 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2098 return $self->new_result($hash);
2105 =item Arguments: \%vals
2107 =item Return Value: a L<DBIx::Class::Row> $object
2111 Attempt to create a single new row or a row with multiple related rows
2112 in the table represented by the resultset (and related tables). This
2113 will not check for duplicate rows before inserting, use
2114 L</find_or_create> to do that.
2116 To create one row for this resultset, pass a hashref of key/value
2117 pairs representing the columns of the table and the values you wish to
2118 store. If the appropriate relationships are set up, foreign key fields
2119 can also be passed an object representing the foreign row, and the
2120 value will be set to its primary key.
2122 To create related objects, pass a hashref for the value if the related
2123 item is a foreign key relationship (L<DBIx::Class::Relationship/belongs_to>),
2124 and use the name of the relationship as the key. (NOT the name of the field,
2125 necessarily). For C<has_many> and C<has_one> relationships, pass an arrayref
2126 of hashrefs containing the data for each of the rows to create in the foreign
2127 tables, again using the relationship name as the key.
2129 Instead of hashrefs of plain related data (key/value pairs), you may
2130 also pass new or inserted objects. New objects (not inserted yet, see
2131 L</new>), will be inserted into their appropriate tables.
2133 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2135 Example of creating a new row.
2137 $person_rs->create({
2138 name=>"Some Person",
2139 email=>"somebody@someplace.com"
2142 Example of creating a new row and also creating rows in a related C<has_many>
2143 or C<has_one> resultset. Note Arrayref.
2146 { artistid => 4, name => 'Manufactured Crap', cds => [
2147 { title => 'My First CD', year => 2006 },
2148 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2153 Example of creating a new row and also creating a row in a related
2154 C<belongs_to>resultset. Note Hashref.
2157 title=>"Music for Silly Walks",
2160 name=>"Silly Musician",
2167 my ($self, $attrs) = @_;
2168 $self->throw_exception( "create needs a hashref" )
2169 unless ref $attrs eq 'HASH';
2170 return $self->new_result($attrs)->insert;
2173 =head2 find_or_create
2177 =item Arguments: \%vals, \%attrs?
2179 =item Return Value: $rowobject
2183 $cd->cd_to_producer->find_or_create({ producer => $producer },
2184 { key => 'primary' });
2186 Tries to find a record based on its primary key or unique constraints; if none
2187 is found, creates one and returns that instead.
2189 my $cd = $schema->resultset('CD')->find_or_create({
2191 artist => 'Massive Attack',
2192 title => 'Mezzanine',
2196 Also takes an optional C<key> attribute, to search by a specific key or unique
2197 constraint. For example:
2199 my $cd = $schema->resultset('CD')->find_or_create(
2201 artist => 'Massive Attack',
2202 title => 'Mezzanine',
2204 { key => 'cd_artist_title' }
2207 B<Note>: Because find_or_create() reads from the database and then
2208 possibly inserts based on the result, this method is subject to a race
2209 condition. Another process could create a record in the table after
2210 the find has completed and before the create has started. To avoid
2211 this problem, use find_or_create() inside a transaction.
2213 B<Note>: C<find_or_create> is probably not what you want when creating
2214 a new row in a table that uses primary keys supplied by the
2215 database. Passing in a primary key column with a value of I<undef>
2216 will cause L</find> to attempt to search for a row with a value of
2219 See also L</find> and L</update_or_create>. For information on how to declare
2220 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2224 sub find_or_create {
2226 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2227 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2228 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2231 return $self->create($hash);
2234 =head2 update_or_create
2238 =item Arguments: \%col_values, { key => $unique_constraint }?
2240 =item Return Value: $rowobject
2244 $resultset->update_or_create({ col => $val, ... });
2246 First, searches for an existing row matching one of the unique constraints
2247 (including the primary key) on the source of this resultset. If a row is
2248 found, updates it with the other given column values. Otherwise, creates a new
2251 Takes an optional C<key> attribute to search on a specific unique constraint.
2254 # In your application
2255 my $cd = $schema->resultset('CD')->update_or_create(
2257 artist => 'Massive Attack',
2258 title => 'Mezzanine',
2261 { key => 'cd_artist_title' }
2264 $cd->cd_to_producer->update_or_create({
2265 producer => $producer,
2272 If no C<key> is specified, it searches on all unique constraints defined on the
2273 source, including the primary key.
2275 If the C<key> is specified as C<primary>, it searches only on the primary key.
2277 See also L</find> and L</find_or_create>. For information on how to declare
2278 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2280 B<Note>: C<update_or_create> is probably not what you want when
2281 looking for a row in a table that uses primary keys supplied by the
2282 database, unless you actually have a key value. Passing in a primary
2283 key column with a value of I<undef> will cause L</find> to attempt to
2284 search for a row with a value of I<NULL>.
2288 sub update_or_create {
2290 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2291 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2293 my $row = $self->find($cond, $attrs);
2295 $row->update($cond);
2299 return $self->create($cond);
2302 =head2 update_or_new
2306 =item Arguments: \%col_values, { key => $unique_constraint }?
2308 =item Return Value: $rowobject
2312 $resultset->update_or_new({ col => $val, ... });
2314 First, searches for an existing row matching one of the unique constraints
2315 (including the primary key) on the source of this resultset. If a row is
2316 found, updates it with the other given column values. Otherwise, instantiate
2317 a new result object and return it. The object will not be saved into your storage
2318 until you call L<DBIx::Class::Row/insert> on it.
2320 Takes an optional C<key> attribute to search on a specific unique constraint.
2323 # In your application
2324 my $cd = $schema->resultset('CD')->update_or_new(
2326 artist => 'Massive Attack',
2327 title => 'Mezzanine',
2330 { key => 'cd_artist_title' }
2333 if ($cd->in_storage) {
2334 # the cd was updated
2337 # the cd is not yet in the database, let's insert it
2341 See also L</find>, L</find_or_create> and L<find_or_new>.
2347 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2348 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2350 my $row = $self->find( $cond, $attrs );
2351 if ( defined $row ) {
2352 $row->update($cond);
2356 return $self->new_result($cond);
2363 =item Arguments: none
2365 =item Return Value: \@cache_objects?
2369 Gets the contents of the cache for the resultset, if the cache is set.
2371 The cache is populated either by using the L</prefetch> attribute to
2372 L</search> or by calling L</set_cache>.
2384 =item Arguments: \@cache_objects
2386 =item Return Value: \@cache_objects
2390 Sets the contents of the cache for the resultset. Expects an arrayref
2391 of objects of the same class as those produced by the resultset. Note that
2392 if the cache is set the resultset will return the cached objects rather
2393 than re-querying the database even if the cache attr is not set.
2395 The contents of the cache can also be populated by using the
2396 L</prefetch> attribute to L</search>.
2401 my ( $self, $data ) = @_;
2402 $self->throw_exception("set_cache requires an arrayref")
2403 if defined($data) && (ref $data ne 'ARRAY');
2404 $self->{all_cache} = $data;
2411 =item Arguments: none
2413 =item Return Value: []
2417 Clears the cache for the resultset.
2422 shift->set_cache(undef);
2425 =head2 related_resultset
2429 =item Arguments: $relationship_name
2431 =item Return Value: $resultset
2435 Returns a related resultset for the supplied relationship name.
2437 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2441 sub related_resultset {
2442 my ($self, $rel) = @_;
2444 $self->{related_resultsets} ||= {};
2445 return $self->{related_resultsets}{$rel} ||= do {
2446 my $rel_info = $self->result_source->relationship_info($rel);
2448 $self->throw_exception(
2449 "search_related: result source '" . $self->result_source->source_name .
2450 "' has no such relationship $rel")
2453 my ($from,$seen) = $self->_resolve_from($rel);
2455 my $join_count = $seen->{$rel};
2456 my $alias = ($join_count > 1 ? join('_', $rel, $join_count) : $rel);
2458 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2459 my %attrs = %{$self->{attrs}||{}};
2460 delete @attrs{qw(result_class alias)};
2464 if (my $cache = $self->get_cache) {
2465 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2466 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
2471 my $rel_source = $self->result_source->related_source($rel);
2475 # The reason we do this now instead of passing the alias to the
2476 # search_rs below is that if you wrap/overload resultset on the
2477 # source you need to know what alias it's -going- to have for things
2478 # to work sanely (e.g. RestrictWithObject wants to be able to add
2479 # extra query restrictions, and these may need to be $alias.)
2481 my $attrs = $rel_source->resultset_attributes;
2482 local $attrs->{alias} = $alias;
2484 $rel_source->resultset
2492 where => $self->{cond},
2497 $new->set_cache($new_cache) if $new_cache;
2502 =head2 current_source_alias
2506 =item Arguments: none
2508 =item Return Value: $source_alias
2512 Returns the current table alias for the result source this resultset is built
2513 on, that will be used in the SQL query. Usually it is C<me>.
2515 Currently the source alias that refers to the result set returned by a
2516 L</search>/L</find> family method depends on how you got to the resultset: it's
2517 C<me> by default, but eg. L</search_related> aliases it to the related result
2518 source name (and keeps C<me> referring to the original result set). The long
2519 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
2520 (and make this method unnecessary).
2522 Thus it's currently necessary to use this method in predefined queries (see
2523 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
2524 source alias of the current result set:
2526 # in a result set class
2528 my ($self, $user) = @_;
2530 my $me = $self->current_source_alias;
2532 return $self->search(
2533 "$me.modified" => $user->id,
2539 sub current_source_alias {
2542 return ($self->{attrs} || {})->{alias} || 'me';
2545 # This code is called by search_related, and makes sure there
2546 # is clear separation between the joins before, during, and
2547 # after the relationship. This information is needed later
2548 # in order to properly resolve prefetch aliases (any alias
2549 # with a relation_chain_depth less than the depth of the
2550 # current prefetch is not considered)
2552 my ($self, $rel) = @_;
2553 my $source = $self->result_source;
2554 my $attrs = $self->{attrs};
2560 -source_handle => $source->handle,
2561 -alias => $attrs->{alias},
2562 $attrs->{alias} => $source->from,
2566 my $seen = { %{$attrs->{seen_join} || {} } };
2568 # we need to take the prefetch the attrs into account before we
2569 # ->_resolve_join as otherwise they get lost - captainL
2570 my $merged = $self->_merge_attr( $attrs->{join}, $attrs->{prefetch} );
2572 push @$from, $source->_resolve_join($merged, $attrs->{alias}, $seen) if ($merged);
2574 ++$seen->{-relation_chain_depth};
2576 push @$from, $source->_resolve_join($rel, $attrs->{alias}, $seen);
2578 ++$seen->{-relation_chain_depth};
2580 return ($from,$seen);
2583 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
2584 sub _resolved_attrs_copy {
2586 return { %{$self->_resolved_attrs (@_)} };
2589 sub _resolved_attrs {
2591 return $self->{_attrs} if $self->{_attrs};
2593 my $attrs = { %{ $self->{attrs} || {} } };
2594 my $source = $self->result_source;
2595 my $alias = $attrs->{alias};
2597 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
2600 # build columns (as long as select isn't set) into a set of as/select hashes
2601 unless ( $attrs->{select} ) {
2603 ( ref($_) eq 'HASH' )
2607 /^\Q${alias}.\E(.+)$/
2618 } ( ref($attrs->{columns}) eq 'ARRAY' ) ? @{ delete $attrs->{columns}} : (delete $attrs->{columns} || $source->columns );
2620 # add the additional columns on
2621 foreach ( 'include_columns', '+columns' ) {
2622 push @colbits, map {
2623 ( ref($_) eq 'HASH' )
2625 : { ( split( /\./, $_ ) )[-1] => ( /\./ ? $_ : "${alias}.$_" ) }
2626 } ( ref($attrs->{$_}) eq 'ARRAY' ) ? @{ delete $attrs->{$_} } : delete $attrs->{$_} if ( $attrs->{$_} );
2629 # start with initial select items
2630 if ( $attrs->{select} ) {
2632 ( ref $attrs->{select} eq 'ARRAY' )
2633 ? [ @{ $attrs->{select} } ]
2634 : [ $attrs->{select} ];
2638 ref $attrs->{as} eq 'ARRAY'
2639 ? [ @{ $attrs->{as} } ]
2642 : [ map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{ $attrs->{select} } ]
2647 # otherwise we intialise select & as to empty
2648 $attrs->{select} = [];
2652 # now add colbits to select/as
2653 push( @{ $attrs->{select} }, map { values( %{$_} ) } @colbits );
2654 push( @{ $attrs->{as} }, map { keys( %{$_} ) } @colbits );
2657 if ( $adds = delete $attrs->{'+select'} ) {
2658 $adds = [$adds] unless ref $adds eq 'ARRAY';
2660 @{ $attrs->{select} },
2661 map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds
2664 if ( $adds = delete $attrs->{'+as'} ) {
2665 $adds = [$adds] unless ref $adds eq 'ARRAY';
2666 push( @{ $attrs->{as} }, @$adds );
2669 $attrs->{from} ||= [ {
2670 -source_handle => $source->handle,
2671 -alias => $self->{attrs}{alias},
2672 $self->{attrs}{alias} => $source->from,
2675 if ( $attrs->{join} || $attrs->{prefetch} ) {
2677 $self->throw_exception ('join/prefetch can not be used with a literal scalarref {from}')
2678 if ref $attrs->{from} ne 'ARRAY';
2680 my $join = delete $attrs->{join} || {};
2682 if ( defined $attrs->{prefetch} ) {
2683 $join = $self->_merge_attr( $join, $attrs->{prefetch} );
2686 $attrs->{from} = # have to copy here to avoid corrupting the original
2688 @{ $attrs->{from} },
2689 $source->_resolve_join(
2690 $join, $alias, { %{ $attrs->{seen_join} || {} } }
2695 if ( $attrs->{order_by} ) {
2696 $attrs->{order_by} = (
2697 ref( $attrs->{order_by} ) eq 'ARRAY'
2698 ? [ @{ $attrs->{order_by} } ]
2699 : [ $attrs->{order_by} ]
2703 $attrs->{order_by} = [];
2706 # If the order_by is otherwise empty - we will use this for TOP limit
2707 # emulation and the like.
2708 # Although this is needed only if the order_by is not defined, it is
2709 # actually cheaper to just populate this rather than properly examining
2710 # order_by (stuf like [ {} ] and the like)
2711 $attrs->{_virtual_order_by} = [ $self->result_source->primary_columns ];
2714 $attrs->{collapse} ||= {};
2715 if ( my $prefetch = delete $attrs->{prefetch} ) {
2716 $prefetch = $self->_merge_attr( {}, $prefetch );
2718 my $prefetch_ordering = [];
2720 my $join_map = $self->_joinpath_aliases ($attrs->{from}, $attrs->{seen_join});
2723 $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
2725 push( @{ $attrs->{select} }, map { $_->[0] } @prefetch );
2726 push( @{ $attrs->{as} }, map { $_->[1] } @prefetch );
2728 push( @{ $attrs->{order_by} }, @$prefetch_ordering );
2729 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
2733 if (delete $attrs->{distinct}) {
2734 $attrs->{group_by} ||= [ grep { !ref($_) || (ref($_) ne 'HASH') } @{$attrs->{select}} ];
2737 # if both page and offset are specified, produce a combined offset
2738 # even though it doesn't make much sense, this is what pre 081xx has
2740 if (my $page = delete $attrs->{page}) {
2741 $attrs->{offset} = ($attrs->{rows} * ($page - 1)) +
2742 ($attrs->{offset} || 0);
2745 return $self->{_attrs} = $attrs;
2748 sub _joinpath_aliases {
2749 my ($self, $fromspec, $seen) = @_;
2752 return $paths unless ref $fromspec eq 'ARRAY';
2754 for my $j (@$fromspec) {
2756 next if ref $j ne 'ARRAY';
2757 next if $j->[0]{-relation_chain_depth} < ( $seen->{-relation_chain_depth} || 0);
2760 $p = $p->{$_} ||= {} for @{$j->[0]{-join_path}};
2761 push @{$p->{-join_aliases} }, $j->[0]{-alias};
2768 my ($self, $attr) = @_;
2770 if (ref $attr eq 'HASH') {
2771 return $self->_rollout_hash($attr);
2772 } elsif (ref $attr eq 'ARRAY') {
2773 return $self->_rollout_array($attr);
2779 sub _rollout_array {
2780 my ($self, $attr) = @_;
2783 foreach my $element (@{$attr}) {
2784 if (ref $element eq 'HASH') {
2785 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
2786 } elsif (ref $element eq 'ARRAY') {
2787 # XXX - should probably recurse here
2788 push( @rolled_array, @{$self->_rollout_array($element)} );
2790 push( @rolled_array, $element );
2793 return \@rolled_array;
2797 my ($self, $attr) = @_;
2800 foreach my $key (keys %{$attr}) {
2801 push( @rolled_array, { $key => $attr->{$key} } );
2803 return \@rolled_array;
2806 sub _calculate_score {
2807 my ($self, $a, $b) = @_;
2809 if (ref $b eq 'HASH') {
2810 my ($b_key) = keys %{$b};
2811 if (ref $a eq 'HASH') {
2812 my ($a_key) = keys %{$a};
2813 if ($a_key eq $b_key) {
2814 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
2819 return ($a eq $b_key) ? 1 : 0;
2822 if (ref $a eq 'HASH') {
2823 my ($a_key) = keys %{$a};
2824 return ($b eq $a_key) ? 1 : 0;
2826 return ($b eq $a) ? 1 : 0;
2832 my ($self, $orig, $import) = @_;
2834 return $import unless defined($orig);
2835 return $orig unless defined($import);
2837 $orig = $self->_rollout_attr($orig);
2838 $import = $self->_rollout_attr($import);
2841 foreach my $import_element ( @{$import} ) {
2842 # find best candidate from $orig to merge $b_element into
2843 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
2844 foreach my $orig_element ( @{$orig} ) {
2845 my $score = $self->_calculate_score( $orig_element, $import_element );
2846 if ($score > $best_candidate->{score}) {
2847 $best_candidate->{position} = $position;
2848 $best_candidate->{score} = $score;
2852 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
2854 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
2855 push( @{$orig}, $import_element );
2857 my $orig_best = $orig->[$best_candidate->{position}];
2858 # merge orig_best and b_element together and replace original with merged
2859 if (ref $orig_best ne 'HASH') {
2860 $orig->[$best_candidate->{position}] = $import_element;
2861 } elsif (ref $import_element eq 'HASH') {
2862 my ($key) = keys %{$orig_best};
2863 $orig->[$best_candidate->{position}] = { $key => $self->_merge_attr($orig_best->{$key}, $import_element->{$key}) };
2866 $seen_keys->{$import_key} = 1; # don't merge the same key twice
2876 $self->_source_handle($_[0]->handle);
2878 $self->_source_handle->resolve;
2882 =head2 throw_exception
2884 See L<DBIx::Class::Schema/throw_exception> for details.
2888 sub throw_exception {
2890 if (ref $self && $self->_source_handle->schema) {
2891 $self->_source_handle->schema->throw_exception(@_)
2898 # XXX: FIXME: Attributes docs need clearing up
2902 Attributes are used to refine a ResultSet in various ways when
2903 searching for data. They can be passed to any method which takes an
2904 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
2907 These are in no particular order:
2913 =item Value: ( $order_by | \@order_by | \%order_by )
2917 Which column(s) to order the results by. If a single column name, or
2918 an arrayref of names is supplied, the argument is passed through
2919 directly to SQL. The hashref syntax allows for connection-agnostic
2920 specification of ordering direction:
2922 For descending order:
2924 order_by => { -desc => [qw/col1 col2 col3/] }
2926 For explicit ascending order:
2928 order_by => { -asc => 'col' }
2930 The old scalarref syntax (i.e. order_by => \'year DESC') is still
2931 supported, although you are strongly encouraged to use the hashref
2932 syntax as outlined above.
2938 =item Value: \@columns
2942 Shortcut to request a particular set of columns to be retrieved. Each
2943 column spec may be a string (a table column name), or a hash (in which
2944 case the key is the C<as> value, and the value is used as the C<select>
2945 expression). Adds C<me.> onto the start of any column without a C<.> in
2946 it and sets C<select> from that, then auto-populates C<as> from
2947 C<select> as normal. (You may also use the C<cols> attribute, as in
2948 earlier versions of DBIC.)
2954 =item Value: \@columns
2958 Indicates additional columns to be selected from storage. Works the same
2959 as L</columns> but adds columns to the selection. (You may also use the
2960 C<include_columns> attribute, as in earlier versions of DBIC). For
2963 $schema->resultset('CD')->search(undef, {
2964 '+columns' => ['artist.name'],
2968 would return all CDs and include a 'name' column to the information
2969 passed to object inflation. Note that the 'artist' is the name of the
2970 column (or relationship) accessor, and 'name' is the name of the column
2971 accessor in the related table.
2973 =head2 include_columns
2977 =item Value: \@columns
2981 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
2987 =item Value: \@select_columns
2991 Indicates which columns should be selected from the storage. You can use
2992 column names, or in the case of RDBMS back ends, function or stored procedure
2995 $rs = $schema->resultset('Employee')->search(undef, {
2998 { count => 'employeeid' },
3003 When you use function/stored procedure names and do not supply an C<as>
3004 attribute, the column names returned are storage-dependent. E.g. MySQL would
3005 return a column named C<count(employeeid)> in the above example.
3011 Indicates additional columns to be selected from storage. Works the same as
3012 L</select> but adds columns to the selection.
3020 Indicates additional column names for those added via L</+select>. See L</as>.
3028 =item Value: \@inflation_names
3032 Indicates column names for object inflation. That is, C<as>
3033 indicates the name that the column can be accessed as via the
3034 C<get_column> method (or via the object accessor, B<if one already
3035 exists>). It has nothing to do with the SQL code C<SELECT foo AS bar>.
3037 The C<as> attribute is used in conjunction with C<select>,
3038 usually when C<select> contains one or more function or stored
3041 $rs = $schema->resultset('Employee')->search(undef, {
3044 { count => 'employeeid' }
3046 as => ['name', 'employee_count'],
3049 my $employee = $rs->first(); # get the first Employee
3051 If the object against which the search is performed already has an accessor
3052 matching a column name specified in C<as>, the value can be retrieved using
3053 the accessor as normal:
3055 my $name = $employee->name();
3057 If on the other hand an accessor does not exist in the object, you need to
3058 use C<get_column> instead:
3060 my $employee_count = $employee->get_column('employee_count');
3062 You can create your own accessors if required - see
3063 L<DBIx::Class::Manual::Cookbook> for details.
3065 Please note: This will NOT insert an C<AS employee_count> into the SQL
3066 statement produced, it is used for internal access only. Thus
3067 attempting to use the accessor in an C<order_by> clause or similar
3068 will fail miserably.
3070 To get around this limitation, you can supply literal SQL to your
3071 C<select> attibute that contains the C<AS alias> text, eg:
3073 select => [\'myfield AS alias']
3079 =item Value: ($rel_name | \@rel_names | \%rel_names)
3083 Contains a list of relationships that should be joined for this query. For
3086 # Get CDs by Nine Inch Nails
3087 my $rs = $schema->resultset('CD')->search(
3088 { 'artist.name' => 'Nine Inch Nails' },
3089 { join => 'artist' }
3092 Can also contain a hash reference to refer to the other relation's relations.
3095 package MyApp::Schema::Track;
3096 use base qw/DBIx::Class/;
3097 __PACKAGE__->table('track');
3098 __PACKAGE__->add_columns(qw/trackid cd position title/);
3099 __PACKAGE__->set_primary_key('trackid');
3100 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3103 # In your application
3104 my $rs = $schema->resultset('Artist')->search(
3105 { 'track.title' => 'Teardrop' },
3107 join => { cd => 'track' },
3108 order_by => 'artist.name',
3112 You need to use the relationship (not the table) name in conditions,
3113 because they are aliased as such. The current table is aliased as "me", so
3114 you need to use me.column_name in order to avoid ambiguity. For example:
3116 # Get CDs from 1984 with a 'Foo' track
3117 my $rs = $schema->resultset('CD')->search(
3120 'tracks.name' => 'Foo'
3122 { join => 'tracks' }
3125 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3126 similarly for a third time). For e.g.
3128 my $rs = $schema->resultset('Artist')->search({
3129 'cds.title' => 'Down to Earth',
3130 'cds_2.title' => 'Popular',
3132 join => [ qw/cds cds/ ],
3135 will return a set of all artists that have both a cd with title 'Down
3136 to Earth' and a cd with title 'Popular'.
3138 If you want to fetch related objects from other tables as well, see C<prefetch>
3141 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3147 =item Value: ($rel_name | \@rel_names | \%rel_names)
3151 Contains one or more relationships that should be fetched along with
3152 the main query (when they are accessed afterwards the data will
3153 already be available, without extra queries to the database). This is
3154 useful for when you know you will need the related objects, because it
3155 saves at least one query:
3157 my $rs = $schema->resultset('Tag')->search(
3166 The initial search results in SQL like the following:
3168 SELECT tag.*, cd.*, artist.* FROM tag
3169 JOIN cd ON tag.cd = cd.cdid
3170 JOIN artist ON cd.artist = artist.artistid
3172 L<DBIx::Class> has no need to go back to the database when we access the
3173 C<cd> or C<artist> relationships, which saves us two SQL statements in this
3176 Simple prefetches will be joined automatically, so there is no need
3177 for a C<join> attribute in the above search.
3179 C<prefetch> can be used with the following relationship types: C<belongs_to>,
3180 C<has_one> (or if you're using C<add_relationship>, any relationship declared
3181 with an accessor type of 'single' or 'filter'). A more complex example that
3182 prefetches an artists cds, the tracks on those cds, and the tags associted
3183 with that artist is given below (assuming many-to-many from artists to tags):
3185 my $rs = $schema->resultset('Artist')->search(
3189 { cds => 'tracks' },
3190 { artist_tags => 'tags' }
3196 B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
3197 attributes will be ignored.
3207 Makes the resultset paged and specifies the page to retrieve. Effectively
3208 identical to creating a non-pages resultset and then calling ->page($page)
3211 If L<rows> attribute is not specified it defualts to 10 rows per page.
3213 When you have a paged resultset, L</count> will only return the number
3214 of rows in the page. To get the total, use the L</pager> and call
3215 C<total_entries> on it.
3225 Specifes the maximum number of rows for direct retrieval or the number of
3226 rows per page if the page attribute or method is used.
3232 =item Value: $offset
3236 Specifies the (zero-based) row number for the first row to be returned, or the
3237 of the first row of the first page if paging is used.
3243 =item Value: \@columns
3247 A arrayref of columns to group by. Can include columns of joined tables.
3249 group_by => [qw/ column1 column2 ... /]
3255 =item Value: $condition
3259 HAVING is a select statement attribute that is applied between GROUP BY and
3260 ORDER BY. It is applied to the after the grouping calculations have been
3263 having => { 'count(employee)' => { '>=', 100 } }
3269 =item Value: (0 | 1)
3273 Set to 1 to group by all columns.
3279 Adds to the WHERE clause.
3281 # only return rows WHERE deleted IS NULL for all searches
3282 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
3284 Can be overridden by passing C<{ where => undef }> as an attribute
3291 Set to 1 to cache search results. This prevents extra SQL queries if you
3292 revisit rows in your ResultSet:
3294 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
3296 while( my $artist = $resultset->next ) {
3300 $rs->first; # without cache, this would issue a query
3302 By default, searches are not cached.
3304 For more examples of using these attributes, see
3305 L<DBIx::Class::Manual::Cookbook>.
3311 =item Value: \@from_clause
3315 The C<from> attribute gives you manual control over the C<FROM> clause of SQL
3316 statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
3319 NOTE: Use this on your own risk. This allows you to shoot off your foot!
3321 C<join> will usually do what you need and it is strongly recommended that you
3322 avoid using C<from> unless you cannot achieve the desired result using C<join>.
3323 And we really do mean "cannot", not just tried and failed. Attempting to use
3324 this because you're having problems with C<join> is like trying to use x86
3325 ASM because you've got a syntax error in your C. Trust us on this.
3327 Now, if you're still really, really sure you need to use this (and if you're
3328 not 100% sure, ask the mailing list first), here's an explanation of how this
3331 The syntax is as follows -
3334 { <alias1> => <table1> },
3336 { <alias2> => <table2>, -join_type => 'inner|left|right' },
3337 [], # nested JOIN (optional)
3338 { <table1.column1> => <table2.column2>, ... (more conditions) },
3340 # More of the above [ ] may follow for additional joins
3347 ON <table1.column1> = <table2.column2>
3348 <more joins may follow>
3350 An easy way to follow the examples below is to remember the following:
3352 Anything inside "[]" is a JOIN
3353 Anything inside "{}" is a condition for the enclosing JOIN
3355 The following examples utilize a "person" table in a family tree application.
3356 In order to express parent->child relationships, this table is self-joined:
3358 # Person->belongs_to('father' => 'Person');
3359 # Person->belongs_to('mother' => 'Person');
3361 C<from> can be used to nest joins. Here we return all children with a father,
3362 then search against all mothers of those children:
3364 $rs = $schema->resultset('Person')->search(
3367 alias => 'mother', # alias columns in accordance with "from"
3369 { mother => 'person' },
3372 { child => 'person' },
3374 { father => 'person' },
3375 { 'father.person_id' => 'child.father_id' }
3378 { 'mother.person_id' => 'child.mother_id' }
3385 # SELECT mother.* FROM person mother
3388 # JOIN person father
3389 # ON ( father.person_id = child.father_id )
3391 # ON ( mother.person_id = child.mother_id )
3393 The type of any join can be controlled manually. To search against only people
3394 with a father in the person table, we could explicitly use C<INNER JOIN>:
3396 $rs = $schema->resultset('Person')->search(
3399 alias => 'child', # alias columns in accordance with "from"
3401 { child => 'person' },
3403 { father => 'person', -join_type => 'inner' },
3404 { 'father.id' => 'child.father_id' }
3411 # SELECT child.* FROM person child
3412 # INNER JOIN person father ON child.father_id = father.id
3414 You can select from a subquery by passing a resultset to from as follows.
3416 $schema->resultset('Artist')->search(
3418 { alias => 'artist2',
3419 from => [ { artist2 => $artist_rs->as_query } ],
3422 # and you'll get sql like this..
3423 # SELECT artist2.artistid, artist2.name, artist2.rank, artist2.charfield FROM
3424 # ( SELECT me.artistid, me.name, me.rank, me.charfield FROM artists me ) artist2
3426 If you need to express really complex joins, you
3427 can supply literal SQL to C<from> via a scalar reference. In this case
3428 the contents of the scalar will replace the table name associated with the
3431 WARNING: This technique might very well not work as expected on chained
3432 searches - you have been warned.
3434 # Assuming the Event resultsource is defined as:
3436 MySchema::Event->add_columns (
3439 is_auto_increment => 1,
3448 MySchema::Event->set_primary_key ('sequence');
3450 # This will get back the latest event for every location. The column
3451 # selector is still provided by DBIC, all we do is add a JOIN/WHERE
3452 # combo to limit the resultset
3454 $rs = $schema->resultset('Event');
3455 $table = $rs->result_source->name;
3456 $latest = $rs->search (
3459 (SELECT e1.* FROM $table e1
3461 ON e1.location = e2.location
3462 AND e1.sequence < e2.sequence
3463 WHERE e2.sequence is NULL
3468 # Equivalent SQL (with the DBIC chunks added):
3470 SELECT me.sequence, me.location, me.type FROM
3471 (SELECT e1.* FROM events e1
3473 ON e1.location = e2.location
3474 AND e1.sequence < e2.sequence
3475 WHERE e2.sequence is NULL
3482 =item Value: ( 'update' | 'shared' )
3486 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT