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 # extra selectors do not go in the subquery and there is no point of ordering it
1247 delete $sub_attrs->{$_} for qw/collapse prefetch_select 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 $self->get_cache;
1314 if (keys %{$self->_resolved_attrs->{collapse}}) {
1315 # Using $self->cursor->all is really just an optimisation.
1316 # If we're collapsing has_many prefetches it probably makes
1317 # very little difference, and this is cleaner than hacking
1318 # _construct_object to survive the approach
1319 $self->cursor->reset;
1320 my @row = $self->cursor->next;
1322 push(@obj, $self->_construct_object(@row));
1323 @row = (exists $self->{stashed_row}
1324 ? @{delete $self->{stashed_row}}
1325 : $self->cursor->next);
1328 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1331 $self->set_cache(\@obj) if $self->{attrs}{cache};
1339 =item Arguments: none
1341 =item Return Value: $self
1345 Resets the resultset's cursor, so you can iterate through the elements again.
1346 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
1353 delete $self->{_attrs} if exists $self->{_attrs};
1354 $self->{all_cache_position} = 0;
1355 $self->cursor->reset;
1363 =item Arguments: none
1365 =item Return Value: $object?
1369 Resets the resultset and returns an object for the first result (if the
1370 resultset returns anything).
1375 return $_[0]->reset->next;
1381 # Determines whether and what type of subquery is required for the $rs operation.
1382 # If grouping is necessary either supplies its own, or verifies the current one
1383 # After all is done delegates to the proper storage method.
1385 sub _rs_update_delete {
1386 my ($self, $op, $values) = @_;
1388 my $rsrc = $self->result_source;
1390 my $needs_group_by_subq = $self->_has_resolved_attr (qw/collapse group_by -join/);
1391 my $needs_subq = $self->_has_resolved_attr (qw/row offset/);
1393 if ($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}.$_" }
1409 (ref $g eq 'ARRAY' ? @$g : $g );
1412 join ("\x00", sort @current_group_by)
1414 join ("\x00", sort @{$attrs->{columns}} )
1416 $self->throw_exception (
1417 "You have just attempted a $op operation on a resultset which does group_by"
1418 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1419 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1420 . ' kind of queries. Please retry the operation with a modified group_by or'
1421 . ' without using one at all.'
1426 $attrs->{group_by} = $attrs->{columns};
1430 my $subrs = (ref $self)->new($rsrc, $attrs);
1432 return $self->result_source->storage->_subq_update_delete($subrs, $op, $values);
1435 return $rsrc->storage->$op(
1437 $op eq 'update' ? $values : (),
1438 $self->_cond_for_update_delete,
1444 # _cond_for_update_delete
1446 # update/delete require the condition to be modified to handle
1447 # the differing SQL syntax available. This transforms the $self->{cond}
1448 # appropriately, returning the new condition.
1450 sub _cond_for_update_delete {
1451 my ($self, $full_cond) = @_;
1454 $full_cond ||= $self->{cond};
1455 # No-op. No condition, we're updating/deleting everything
1456 return $cond unless ref $full_cond;
1458 if (ref $full_cond eq 'ARRAY') {
1462 foreach my $key (keys %{$_}) {
1464 $hash{$1} = $_->{$key};
1470 elsif (ref $full_cond eq 'HASH') {
1471 if ((keys %{$full_cond})[0] eq '-and') {
1473 my @cond = @{$full_cond->{-and}};
1474 for (my $i = 0; $i < @cond; $i++) {
1475 my $entry = $cond[$i];
1477 if (ref $entry eq 'HASH') {
1478 $hash = $self->_cond_for_update_delete($entry);
1481 $entry =~ /([^.]+)$/;
1482 $hash->{$1} = $cond[++$i];
1484 push @{$cond->{-and}}, $hash;
1488 foreach my $key (keys %{$full_cond}) {
1490 $cond->{$1} = $full_cond->{$key};
1495 $self->throw_exception("Can't update/delete on resultset with condition unless hash or array");
1506 =item Arguments: \%values
1508 =item Return Value: $storage_rv
1512 Sets the specified columns in the resultset to the supplied values in a
1513 single query. Return value will be true if the update succeeded or false
1514 if no records were updated; exact type of success value is storage-dependent.
1519 my ($self, $values) = @_;
1520 $self->throw_exception('Values for update must be a hash')
1521 unless ref $values eq 'HASH';
1523 return $self->_rs_update_delete ('update', $values);
1530 =item Arguments: \%values
1532 =item Return Value: 1
1536 Fetches all objects and updates them one at a time. Note that C<update_all>
1537 will run DBIC cascade triggers, while L</update> will not.
1542 my ($self, $values) = @_;
1543 $self->throw_exception('Values for update_all must be a hash')
1544 unless ref $values eq 'HASH';
1545 foreach my $obj ($self->all) {
1546 $obj->set_columns($values)->update;
1555 =item Arguments: none
1557 =item Return Value: $storage_rv
1561 Deletes the contents of the resultset from its result source. Note that this
1562 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1563 to run. See also L<DBIx::Class::Row/delete>.
1565 Return value will be the amount of rows deleted; exact type of return value
1566 is storage-dependent.
1572 $self->throw_exception('delete does not accept any arguments')
1575 return $self->_rs_update_delete ('delete');
1582 =item Arguments: none
1584 =item Return Value: 1
1588 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1589 will run DBIC cascade triggers, while L</delete> will not.
1595 $self->throw_exception('delete_all does not accept any arguments')
1598 $_->delete for $self->all;
1606 =item Arguments: \@data;
1610 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1611 For the arrayref of hashrefs style each hashref should be a structure suitable
1612 forsubmitting to a $resultset->create(...) method.
1614 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1615 to insert the data, as this is a faster method.
1617 Otherwise, each set of data is inserted into the database using
1618 L<DBIx::Class::ResultSet/create>, and the resulting objects are
1619 accumulated into an array. The array itself, or an array reference
1620 is returned depending on scalar or list context.
1622 Example: Assuming an Artist Class that has many CDs Classes relating:
1624 my $Artist_rs = $schema->resultset("Artist");
1626 ## Void Context Example
1627 $Artist_rs->populate([
1628 { artistid => 4, name => 'Manufactured Crap', cds => [
1629 { title => 'My First CD', year => 2006 },
1630 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1633 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1634 { title => 'My parents sold me to a record company' ,year => 2005 },
1635 { title => 'Why Am I So Ugly?', year => 2006 },
1636 { title => 'I Got Surgery and am now Popular', year => 2007 }
1641 ## Array Context Example
1642 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1643 { name => "Artist One"},
1644 { name => "Artist Two"},
1645 { name => "Artist Three", cds=> [
1646 { title => "First CD", year => 2007},
1647 { title => "Second CD", year => 2008},
1651 print $ArtistOne->name; ## response is 'Artist One'
1652 print $ArtistThree->cds->count ## reponse is '2'
1654 For the arrayref of arrayrefs style, the first element should be a list of the
1655 fieldsnames to which the remaining elements are rows being inserted. For
1658 $Arstist_rs->populate([
1659 [qw/artistid name/],
1660 [100, 'A Formally Unknown Singer'],
1661 [101, 'A singer that jumped the shark two albums ago'],
1662 [102, 'An actually cool singer.'],
1665 Please note an important effect on your data when choosing between void and
1666 wantarray context. Since void context goes straight to C<insert_bulk> in
1667 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
1668 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
1669 create primary keys for you, you will find that your PKs are empty. In this
1670 case you will have to use the wantarray context in order to create those
1676 my $self = shift @_;
1677 my $data = ref $_[0][0] eq 'HASH'
1678 ? $_[0] : ref $_[0][0] eq 'ARRAY' ? $self->_normalize_populate_args($_[0]) :
1679 $self->throw_exception('Populate expects an arrayref of hashes or arrayref of arrayrefs');
1681 if(defined wantarray) {
1683 foreach my $item (@$data) {
1684 push(@created, $self->create($item));
1686 return wantarray ? @created : \@created;
1688 my ($first, @rest) = @$data;
1690 my @names = grep {!ref $first->{$_}} keys %$first;
1691 my @rels = grep { $self->result_source->has_relationship($_) } keys %$first;
1692 my @pks = $self->result_source->primary_columns;
1694 ## do the belongs_to relationships
1695 foreach my $index (0..$#$data) {
1697 # delegate to create() for any dataset without primary keys with specified relationships
1698 if (grep { !defined $data->[$index]->{$_} } @pks ) {
1700 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
1701 my @ret = $self->populate($data);
1707 foreach my $rel (@rels) {
1708 next unless ref $data->[$index]->{$rel} eq "HASH";
1709 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1710 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1711 my $related = $result->result_source->_resolve_condition(
1712 $result->result_source->relationship_info($reverse)->{cond},
1717 delete $data->[$index]->{$rel};
1718 $data->[$index] = {%{$data->[$index]}, %$related};
1720 push @names, keys %$related if $index == 0;
1724 ## do bulk insert on current row
1725 my @values = map { [ @$_{@names} ] } @$data;
1727 $self->result_source->storage->insert_bulk(
1728 $self->result_source,
1733 ## do the has_many relationships
1734 foreach my $item (@$data) {
1736 foreach my $rel (@rels) {
1737 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1739 my $parent = $self->find(map {{$_=>$item->{$_}} } @pks)
1740 || $self->throw_exception('Cannot find the relating object.');
1742 my $child = $parent->$rel;
1744 my $related = $child->result_source->_resolve_condition(
1745 $parent->result_source->relationship_info($rel)->{cond},
1750 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1751 my @populate = map { {%$_, %$related} } @rows_to_add;
1753 $child->populate( \@populate );
1759 =head2 _normalize_populate_args ($args)
1761 Private method used by L</populate> to normalize its incoming arguments. Factored
1762 out in case you want to subclass and accept new argument structures to the
1763 L</populate> method.
1767 sub _normalize_populate_args {
1768 my ($self, $data) = @_;
1769 my @names = @{shift(@$data)};
1770 my @results_to_create;
1771 foreach my $datum (@$data) {
1772 my %result_to_create;
1773 foreach my $index (0..$#names) {
1774 $result_to_create{$names[$index]} = $$datum[$index];
1776 push @results_to_create, \%result_to_create;
1778 return \@results_to_create;
1785 =item Arguments: none
1787 =item Return Value: $pager
1791 Return Value a L<Data::Page> object for the current resultset. Only makes
1792 sense for queries with a C<page> attribute.
1794 To get the full count of entries for a paged resultset, call
1795 C<total_entries> on the L<Data::Page> object.
1802 return $self->{pager} if $self->{pager};
1804 my $attrs = $self->{attrs};
1805 $self->throw_exception("Can't create pager for non-paged rs")
1806 unless $self->{attrs}{page};
1807 $attrs->{rows} ||= 10;
1809 # throw away the paging flags and re-run the count (possibly
1810 # with a subselect) to get the real total count
1811 my $count_attrs = { %$attrs };
1812 delete $count_attrs->{$_} for qw/rows offset page pager/;
1813 my $total_count = (ref $self)->new($self->result_source, $count_attrs)->count;
1815 return $self->{pager} = Data::Page->new(
1818 $self->{attrs}{page}
1826 =item Arguments: $page_number
1828 =item Return Value: $rs
1832 Returns a resultset for the $page_number page of the resultset on which page
1833 is called, where each page contains a number of rows equal to the 'rows'
1834 attribute set on the resultset (10 by default).
1839 my ($self, $page) = @_;
1840 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1847 =item Arguments: \%vals
1849 =item Return Value: $rowobject
1853 Creates a new row object in the resultset's result class and returns
1854 it. The row is not inserted into the database at this point, call
1855 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
1856 will tell you whether the row object has been inserted or not.
1858 Passes the hashref of input on to L<DBIx::Class::Row/new>.
1863 my ($self, $values) = @_;
1864 $self->throw_exception( "new_result needs a hash" )
1865 unless (ref $values eq 'HASH');
1868 my $alias = $self->{attrs}{alias};
1871 defined $self->{cond}
1872 && $self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION
1874 %new = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
1875 $new{-from_resultset} = [ keys %new ] if keys %new;
1877 $self->throw_exception(
1878 "Can't abstract implicit construct, condition not a hash"
1879 ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
1881 my $collapsed_cond = (
1883 ? $self->_collapse_cond($self->{cond})
1887 # precendence must be given to passed values over values inherited from
1888 # the cond, so the order here is important.
1889 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
1890 while( my($col,$value) = each %implied ){
1891 if(ref($value) eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '='){
1892 $new{$col} = $value->{'='};
1895 $new{$col} = $value if $self->_is_deterministic_value($value);
1901 %{ $self->_remove_alias($values, $alias) },
1902 -source_handle => $self->_source_handle,
1903 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
1906 return $self->result_class->new(\%new);
1909 # _is_deterministic_value
1911 # Make an effor to strip non-deterministic values from the condition,
1912 # to make sure new_result chokes less
1914 sub _is_deterministic_value {
1917 my $ref_type = ref $value;
1918 return 1 if $ref_type eq '' || $ref_type eq 'SCALAR';
1919 return 1 if Scalar::Util::blessed($value);
1923 # _has_resolved_attr
1925 # determines if the resultset defines at least one
1926 # of the attributes supplied
1928 # used to determine if a subquery is neccessary
1930 sub _has_resolved_attr {
1931 my ($self, @attr_names) = @_;
1933 my $attrs = $self->_resolved_attrs;
1937 for my $n (@attr_names) {
1938 ++$join_check_req if $n eq '-join';
1940 my $attr = $attrs->{$n};
1942 next if not defined $attr;
1944 if (ref $attr eq 'HASH') {
1945 return 1 if keys %$attr;
1947 elsif (ref $attr eq 'ARRAY') {
1955 # a resolved join is expressed as a multi-level from
1959 ref $attrs->{from} eq 'ARRAY'
1961 @{$attrs->{from}} > 1
1969 # Recursively collapse the condition.
1971 sub _collapse_cond {
1972 my ($self, $cond, $collapsed) = @_;
1976 if (ref $cond eq 'ARRAY') {
1977 foreach my $subcond (@$cond) {
1978 next unless ref $subcond; # -or
1979 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1982 elsif (ref $cond eq 'HASH') {
1983 if (keys %$cond and (keys %$cond)[0] eq '-and') {
1984 foreach my $subcond (@{$cond->{-and}}) {
1985 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1989 foreach my $col (keys %$cond) {
1990 my $value = $cond->{$col};
1991 $collapsed->{$col} = $value;
2001 # Remove the specified alias from the specified query hash. A copy is made so
2002 # the original query is not modified.
2005 my ($self, $query, $alias) = @_;
2007 my %orig = %{ $query || {} };
2010 foreach my $key (keys %orig) {
2012 $unaliased{$key} = $orig{$key};
2015 $unaliased{$1} = $orig{$key}
2016 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2022 =head2 as_query (EXPERIMENTAL)
2026 =item Arguments: none
2028 =item Return Value: \[ $sql, @bind ]
2032 Returns the SQL query and bind vars associated with the invocant.
2034 This is generally used as the RHS for a subquery.
2036 B<NOTE>: This feature is still experimental.
2043 my $attrs = $self->_resolved_attrs_copy;
2048 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2049 # $sql also has no wrapping parenthesis in list ctx
2051 my $sqlbind = $self->result_source->storage
2052 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2061 =item Arguments: \%vals, \%attrs?
2063 =item Return Value: $rowobject
2067 my $artist = $schema->resultset('Artist')->find_or_new(
2068 { artist => 'fred' }, { key => 'artists' });
2070 $cd->cd_to_producer->find_or_new({ producer => $producer },
2071 { key => 'primary });
2073 Find an existing record from this resultset, based on its primary
2074 key, or a unique constraint. If none exists, instantiate a new result
2075 object and return it. The object will not be saved into your storage
2076 until you call L<DBIx::Class::Row/insert> on it.
2078 You most likely want this method when looking for existing rows using
2079 a unique constraint that is not the primary key, or looking for
2082 If you want objects to be saved immediately, use L</find_or_create> instead.
2084 B<Note>: C<find_or_new> is probably not what you want when creating a
2085 new row in a table that uses primary keys supplied by the
2086 database. Passing in a primary key column with a value of I<undef>
2087 will cause L</find> to attempt to search for a row with a value of
2094 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2095 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2096 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2099 return $self->new_result($hash);
2106 =item Arguments: \%vals
2108 =item Return Value: a L<DBIx::Class::Row> $object
2112 Attempt to create a single new row or a row with multiple related rows
2113 in the table represented by the resultset (and related tables). This
2114 will not check for duplicate rows before inserting, use
2115 L</find_or_create> to do that.
2117 To create one row for this resultset, pass a hashref of key/value
2118 pairs representing the columns of the table and the values you wish to
2119 store. If the appropriate relationships are set up, foreign key fields
2120 can also be passed an object representing the foreign row, and the
2121 value will be set to its primary key.
2123 To create related objects, pass a hashref for the value if the related
2124 item is a foreign key relationship (L<DBIx::Class::Relationship/belongs_to>),
2125 and use the name of the relationship as the key. (NOT the name of the field,
2126 necessarily). For C<has_many> and C<has_one> relationships, pass an arrayref
2127 of hashrefs containing the data for each of the rows to create in the foreign
2128 tables, again using the relationship name as the key.
2130 Instead of hashrefs of plain related data (key/value pairs), you may
2131 also pass new or inserted objects. New objects (not inserted yet, see
2132 L</new>), will be inserted into their appropriate tables.
2134 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2136 Example of creating a new row.
2138 $person_rs->create({
2139 name=>"Some Person",
2140 email=>"somebody@someplace.com"
2143 Example of creating a new row and also creating rows in a related C<has_many>
2144 or C<has_one> resultset. Note Arrayref.
2147 { artistid => 4, name => 'Manufactured Crap', cds => [
2148 { title => 'My First CD', year => 2006 },
2149 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2154 Example of creating a new row and also creating a row in a related
2155 C<belongs_to>resultset. Note Hashref.
2158 title=>"Music for Silly Walks",
2161 name=>"Silly Musician",
2168 my ($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>: C<find_or_create> is probably not what you want when creating
2215 a new row in a table that uses primary keys supplied by the
2216 database. Passing in a primary key column with a value of I<undef>
2217 will cause L</find> to attempt to search for a row with a value of
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>: C<update_or_create> is probably not what you want when
2282 looking for a row in a table that uses primary keys supplied by the
2283 database, unless you actually have a key value. Passing in a primary
2284 key column with a value of I<undef> will cause L</find> to attempt to
2285 search for a row with a value of I<NULL>.
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 See also L</find>, L</find_or_create> and L<find_or_new>.
2348 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2349 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2351 my $row = $self->find( $cond, $attrs );
2352 if ( defined $row ) {
2353 $row->update($cond);
2357 return $self->new_result($cond);
2364 =item Arguments: none
2366 =item Return Value: \@cache_objects?
2370 Gets the contents of the cache for the resultset, if the cache is set.
2372 The cache is populated either by using the L</prefetch> attribute to
2373 L</search> or by calling L</set_cache>.
2385 =item Arguments: \@cache_objects
2387 =item Return Value: \@cache_objects
2391 Sets the contents of the cache for the resultset. Expects an arrayref
2392 of objects of the same class as those produced by the resultset. Note that
2393 if the cache is set the resultset will return the cached objects rather
2394 than re-querying the database even if the cache attr is not set.
2396 The contents of the cache can also be populated by using the
2397 L</prefetch> attribute to L</search>.
2402 my ( $self, $data ) = @_;
2403 $self->throw_exception("set_cache requires an arrayref")
2404 if defined($data) && (ref $data ne 'ARRAY');
2405 $self->{all_cache} = $data;
2412 =item Arguments: none
2414 =item Return Value: []
2418 Clears the cache for the resultset.
2423 shift->set_cache(undef);
2426 =head2 related_resultset
2430 =item Arguments: $relationship_name
2432 =item Return Value: $resultset
2436 Returns a related resultset for the supplied relationship name.
2438 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2442 sub related_resultset {
2443 my ($self, $rel) = @_;
2445 $self->{related_resultsets} ||= {};
2446 return $self->{related_resultsets}{$rel} ||= do {
2447 my $rel_info = $self->result_source->relationship_info($rel);
2449 $self->throw_exception(
2450 "search_related: result source '" . $self->result_source->source_name .
2451 "' has no such relationship $rel")
2454 my ($from,$seen) = $self->_chain_relationship($rel);
2456 my $join_count = $seen->{$rel};
2457 my $alias = ($join_count > 1 ? join('_', $rel, $join_count) : $rel);
2459 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2460 my %attrs = %{$self->{attrs}||{}};
2461 delete @attrs{qw(result_class alias)};
2465 if (my $cache = $self->get_cache) {
2466 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2467 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
2472 my $rel_source = $self->result_source->related_source($rel);
2476 # The reason we do this now instead of passing the alias to the
2477 # search_rs below is that if you wrap/overload resultset on the
2478 # source you need to know what alias it's -going- to have for things
2479 # to work sanely (e.g. RestrictWithObject wants to be able to add
2480 # extra query restrictions, and these may need to be $alias.)
2482 my $attrs = $rel_source->resultset_attributes;
2483 local $attrs->{alias} = $alias;
2485 $rel_source->resultset
2493 where => $self->{cond},
2498 $new->set_cache($new_cache) if $new_cache;
2503 =head2 current_source_alias
2507 =item Arguments: none
2509 =item Return Value: $source_alias
2513 Returns the current table alias for the result source this resultset is built
2514 on, that will be used in the SQL query. Usually it is C<me>.
2516 Currently the source alias that refers to the result set returned by a
2517 L</search>/L</find> family method depends on how you got to the resultset: it's
2518 C<me> by default, but eg. L</search_related> aliases it to the related result
2519 source name (and keeps C<me> referring to the original result set). The long
2520 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
2521 (and make this method unnecessary).
2523 Thus it's currently necessary to use this method in predefined queries (see
2524 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
2525 source alias of the current result set:
2527 # in a result set class
2529 my ($self, $user) = @_;
2531 my $me = $self->current_source_alias;
2533 return $self->search(
2534 "$me.modified" => $user->id,
2540 sub current_source_alias {
2543 return ($self->{attrs} || {})->{alias} || 'me';
2546 # This code is called by search_related, and makes sure there
2547 # is clear separation between the joins before, during, and
2548 # after the relationship. This information is needed later
2549 # in order to properly resolve prefetch aliases (any alias
2550 # with a relation_chain_depth less than the depth of the
2551 # current prefetch is not considered)
2552 sub _chain_relationship {
2553 my ($self, $rel) = @_;
2554 my $source = $self->result_source;
2555 my $attrs = $self->{attrs};
2561 -source_handle => $source->handle,
2562 -alias => $attrs->{alias},
2563 $attrs->{alias} => $source->from,
2567 my $seen = { %{$attrs->{seen_join} || {} } };
2569 # we need to take the prefetch the attrs into account before we
2570 # ->_resolve_join as otherwise they get lost - captainL
2571 my $merged = $self->_merge_attr( $attrs->{join}, $attrs->{prefetch} );
2573 my @requested_joins = $source->_resolve_join($merged, $attrs->{alias}, $seen);
2575 push @$from, @requested_joins;
2577 ++$seen->{-relation_chain_depth};
2579 # if $self already had a join/prefetch specified on it, the requested
2580 # $rel might very well be already included. What we do in this case
2581 # is effectively a no-op (except that we bump up the chain_depth on
2582 # the join in question so we could tell it *is* the search_related)
2585 # we consider the last one thus reverse
2586 for my $j (reverse @requested_joins) {
2587 if ($rel eq $j->[0]{-join_path}[-1]) {
2588 $j->[0]{-relation_chain_depth}++;
2593 unless ($already_joined) {
2594 push @$from, $source->_resolve_join($rel, $attrs->{alias}, $seen);
2597 ++$seen->{-relation_chain_depth};
2599 return ($from,$seen);
2602 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
2603 sub _resolved_attrs_copy {
2605 return { %{$self->_resolved_attrs (@_)} };
2608 sub _resolved_attrs {
2610 return $self->{_attrs} if $self->{_attrs};
2612 my $attrs = { %{ $self->{attrs} || {} } };
2613 my $source = $self->result_source;
2614 my $alias = $attrs->{alias};
2616 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
2619 # build columns (as long as select isn't set) into a set of as/select hashes
2620 unless ( $attrs->{select} ) {
2622 ( ref($_) eq 'HASH' )
2626 /^\Q${alias}.\E(.+)$/
2637 } ( ref($attrs->{columns}) eq 'ARRAY' ) ? @{ delete $attrs->{columns}} : (delete $attrs->{columns} || $source->columns );
2639 # add the additional columns on
2640 foreach ( 'include_columns', '+columns' ) {
2641 push @colbits, map {
2642 ( ref($_) eq 'HASH' )
2644 : { ( split( /\./, $_ ) )[-1] => ( /\./ ? $_ : "${alias}.$_" ) }
2645 } ( ref($attrs->{$_}) eq 'ARRAY' ) ? @{ delete $attrs->{$_} } : delete $attrs->{$_} if ( $attrs->{$_} );
2648 # start with initial select items
2649 if ( $attrs->{select} ) {
2651 ( ref $attrs->{select} eq 'ARRAY' )
2652 ? [ @{ $attrs->{select} } ]
2653 : [ $attrs->{select} ];
2657 ref $attrs->{as} eq 'ARRAY'
2658 ? [ @{ $attrs->{as} } ]
2661 : [ map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{ $attrs->{select} } ]
2666 # otherwise we intialise select & as to empty
2667 $attrs->{select} = [];
2671 # now add colbits to select/as
2672 push( @{ $attrs->{select} }, map { values( %{$_} ) } @colbits );
2673 push( @{ $attrs->{as} }, map { keys( %{$_} ) } @colbits );
2676 if ( $adds = delete $attrs->{'+select'} ) {
2677 $adds = [$adds] unless ref $adds eq 'ARRAY';
2679 @{ $attrs->{select} },
2680 map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds
2683 if ( $adds = delete $attrs->{'+as'} ) {
2684 $adds = [$adds] unless ref $adds eq 'ARRAY';
2685 push( @{ $attrs->{as} }, @$adds );
2688 $attrs->{from} ||= [ {
2689 -source_handle => $source->handle,
2690 -alias => $self->{attrs}{alias},
2691 $self->{attrs}{alias} => $source->from,
2694 if ( $attrs->{join} || $attrs->{prefetch} ) {
2696 $self->throw_exception ('join/prefetch can not be used with a literal scalarref {from}')
2697 if ref $attrs->{from} ne 'ARRAY';
2699 my $join = delete $attrs->{join} || {};
2701 if ( defined $attrs->{prefetch} ) {
2702 $join = $self->_merge_attr( $join, $attrs->{prefetch} );
2705 $attrs->{from} = # have to copy here to avoid corrupting the original
2707 @{ $attrs->{from} },
2708 $source->_resolve_join(
2709 $join, $alias, { %{ $attrs->{seen_join} || {} } }
2714 if ( $attrs->{order_by} ) {
2715 $attrs->{order_by} = (
2716 ref( $attrs->{order_by} ) eq 'ARRAY'
2717 ? [ @{ $attrs->{order_by} } ]
2718 : [ $attrs->{order_by} ]
2722 if ($attrs->{group_by} and ! ref $attrs->{group_by}) {
2723 $attrs->{group_by} = [ $attrs->{group_by} ];
2726 # If the order_by is otherwise empty - we will use this for TOP limit
2727 # emulation and the like.
2728 # Although this is needed only if the order_by is not defined, it is
2729 # actually cheaper to just populate this rather than properly examining
2730 # order_by (stuf like [ {} ] and the like)
2731 $attrs->{_virtual_order_by} = [ $self->result_source->primary_columns ];
2734 $attrs->{collapse} ||= {};
2735 if ( my $prefetch = delete $attrs->{prefetch} ) {
2736 $prefetch = $self->_merge_attr( {}, $prefetch );
2738 my $prefetch_ordering = [];
2740 my $join_map = $self->_joinpath_aliases ($attrs->{from}, $attrs->{seen_join});
2743 $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
2745 $attrs->{prefetch_select} = [ map { $_->[0] } @prefetch ];
2746 push @{ $attrs->{select} }, @{$attrs->{prefetch_select}};
2747 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
2749 push( @{ $attrs->{order_by} }, @$prefetch_ordering );
2750 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
2754 if (delete $attrs->{distinct}) {
2755 $attrs->{group_by} ||= [ grep { !ref($_) || (ref($_) ne 'HASH') } @{$attrs->{select}} ];
2758 # if both page and offset are specified, produce a combined offset
2759 # even though it doesn't make much sense, this is what pre 081xx has
2761 if (my $page = delete $attrs->{page}) {
2762 $attrs->{offset} = ($attrs->{rows} * ($page - 1)) +
2763 ($attrs->{offset} || 0);
2766 return $self->{_attrs} = $attrs;
2769 sub _joinpath_aliases {
2770 my ($self, $fromspec, $seen) = @_;
2773 return $paths unless ref $fromspec eq 'ARRAY';
2775 for my $j (@$fromspec) {
2777 next if ref $j ne 'ARRAY';
2778 next if $j->[0]{-relation_chain_depth} < ( $seen->{-relation_chain_depth} || 0);
2781 $p = $p->{$_} ||= {} for @{$j->[0]{-join_path}};
2782 push @{$p->{-join_aliases} }, $j->[0]{-alias};
2789 my ($self, $attr) = @_;
2791 if (ref $attr eq 'HASH') {
2792 return $self->_rollout_hash($attr);
2793 } elsif (ref $attr eq 'ARRAY') {
2794 return $self->_rollout_array($attr);
2800 sub _rollout_array {
2801 my ($self, $attr) = @_;
2804 foreach my $element (@{$attr}) {
2805 if (ref $element eq 'HASH') {
2806 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
2807 } elsif (ref $element eq 'ARRAY') {
2808 # XXX - should probably recurse here
2809 push( @rolled_array, @{$self->_rollout_array($element)} );
2811 push( @rolled_array, $element );
2814 return \@rolled_array;
2818 my ($self, $attr) = @_;
2821 foreach my $key (keys %{$attr}) {
2822 push( @rolled_array, { $key => $attr->{$key} } );
2824 return \@rolled_array;
2827 sub _calculate_score {
2828 my ($self, $a, $b) = @_;
2830 if (ref $b eq 'HASH') {
2831 my ($b_key) = keys %{$b};
2832 if (ref $a eq 'HASH') {
2833 my ($a_key) = keys %{$a};
2834 if ($a_key eq $b_key) {
2835 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
2840 return ($a eq $b_key) ? 1 : 0;
2843 if (ref $a eq 'HASH') {
2844 my ($a_key) = keys %{$a};
2845 return ($b eq $a_key) ? 1 : 0;
2847 return ($b eq $a) ? 1 : 0;
2853 my ($self, $orig, $import) = @_;
2855 return $import unless defined($orig);
2856 return $orig unless defined($import);
2858 $orig = $self->_rollout_attr($orig);
2859 $import = $self->_rollout_attr($import);
2862 foreach my $import_element ( @{$import} ) {
2863 # find best candidate from $orig to merge $b_element into
2864 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
2865 foreach my $orig_element ( @{$orig} ) {
2866 my $score = $self->_calculate_score( $orig_element, $import_element );
2867 if ($score > $best_candidate->{score}) {
2868 $best_candidate->{position} = $position;
2869 $best_candidate->{score} = $score;
2873 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
2875 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
2876 push( @{$orig}, $import_element );
2878 my $orig_best = $orig->[$best_candidate->{position}];
2879 # merge orig_best and b_element together and replace original with merged
2880 if (ref $orig_best ne 'HASH') {
2881 $orig->[$best_candidate->{position}] = $import_element;
2882 } elsif (ref $import_element eq 'HASH') {
2883 my ($key) = keys %{$orig_best};
2884 $orig->[$best_candidate->{position}] = { $key => $self->_merge_attr($orig_best->{$key}, $import_element->{$key}) };
2887 $seen_keys->{$import_key} = 1; # don't merge the same key twice
2897 $self->_source_handle($_[0]->handle);
2899 $self->_source_handle->resolve;
2903 =head2 throw_exception
2905 See L<DBIx::Class::Schema/throw_exception> for details.
2909 sub throw_exception {
2911 if (ref $self && $self->_source_handle->schema) {
2912 $self->_source_handle->schema->throw_exception(@_)
2919 # XXX: FIXME: Attributes docs need clearing up
2923 Attributes are used to refine a ResultSet in various ways when
2924 searching for data. They can be passed to any method which takes an
2925 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
2928 These are in no particular order:
2934 =item Value: ( $order_by | \@order_by | \%order_by )
2938 Which column(s) to order the results by. If a single column name, or
2939 an arrayref of names is supplied, the argument is passed through
2940 directly to SQL. The hashref syntax allows for connection-agnostic
2941 specification of ordering direction:
2943 For descending order:
2945 order_by => { -desc => [qw/col1 col2 col3/] }
2947 For explicit ascending order:
2949 order_by => { -asc => 'col' }
2951 The old scalarref syntax (i.e. order_by => \'year DESC') is still
2952 supported, although you are strongly encouraged to use the hashref
2953 syntax as outlined above.
2959 =item Value: \@columns
2963 Shortcut to request a particular set of columns to be retrieved. Each
2964 column spec may be a string (a table column name), or a hash (in which
2965 case the key is the C<as> value, and the value is used as the C<select>
2966 expression). Adds C<me.> onto the start of any column without a C<.> in
2967 it and sets C<select> from that, then auto-populates C<as> from
2968 C<select> as normal. (You may also use the C<cols> attribute, as in
2969 earlier versions of DBIC.)
2975 =item Value: \@columns
2979 Indicates additional columns to be selected from storage. Works the same
2980 as L</columns> but adds columns to the selection. (You may also use the
2981 C<include_columns> attribute, as in earlier versions of DBIC). For
2984 $schema->resultset('CD')->search(undef, {
2985 '+columns' => ['artist.name'],
2989 would return all CDs and include a 'name' column to the information
2990 passed to object inflation. Note that the 'artist' is the name of the
2991 column (or relationship) accessor, and 'name' is the name of the column
2992 accessor in the related table.
2994 =head2 include_columns
2998 =item Value: \@columns
3002 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3008 =item Value: \@select_columns
3012 Indicates which columns should be selected from the storage. You can use
3013 column names, or in the case of RDBMS back ends, function or stored procedure
3016 $rs = $schema->resultset('Employee')->search(undef, {
3019 { count => 'employeeid' },
3024 When you use function/stored procedure names and do not supply an C<as>
3025 attribute, the column names returned are storage-dependent. E.g. MySQL would
3026 return a column named C<count(employeeid)> in the above example.
3032 Indicates additional columns to be selected from storage. Works the same as
3033 L</select> but adds columns to the selection.
3041 Indicates additional column names for those added via L</+select>. See L</as>.
3049 =item Value: \@inflation_names
3053 Indicates column names for object inflation. That is, C<as>
3054 indicates the name that the column can be accessed as via the
3055 C<get_column> method (or via the object accessor, B<if one already
3056 exists>). It has nothing to do with the SQL code C<SELECT foo AS bar>.
3058 The C<as> attribute is used in conjunction with C<select>,
3059 usually when C<select> contains one or more function or stored
3062 $rs = $schema->resultset('Employee')->search(undef, {
3065 { count => 'employeeid' }
3067 as => ['name', 'employee_count'],
3070 my $employee = $rs->first(); # get the first Employee
3072 If the object against which the search is performed already has an accessor
3073 matching a column name specified in C<as>, the value can be retrieved using
3074 the accessor as normal:
3076 my $name = $employee->name();
3078 If on the other hand an accessor does not exist in the object, you need to
3079 use C<get_column> instead:
3081 my $employee_count = $employee->get_column('employee_count');
3083 You can create your own accessors if required - see
3084 L<DBIx::Class::Manual::Cookbook> for details.
3086 Please note: This will NOT insert an C<AS employee_count> into the SQL
3087 statement produced, it is used for internal access only. Thus
3088 attempting to use the accessor in an C<order_by> clause or similar
3089 will fail miserably.
3091 To get around this limitation, you can supply literal SQL to your
3092 C<select> attibute that contains the C<AS alias> text, eg:
3094 select => [\'myfield AS alias']
3100 =item Value: ($rel_name | \@rel_names | \%rel_names)
3104 Contains a list of relationships that should be joined for this query. For
3107 # Get CDs by Nine Inch Nails
3108 my $rs = $schema->resultset('CD')->search(
3109 { 'artist.name' => 'Nine Inch Nails' },
3110 { join => 'artist' }
3113 Can also contain a hash reference to refer to the other relation's relations.
3116 package MyApp::Schema::Track;
3117 use base qw/DBIx::Class/;
3118 __PACKAGE__->table('track');
3119 __PACKAGE__->add_columns(qw/trackid cd position title/);
3120 __PACKAGE__->set_primary_key('trackid');
3121 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3124 # In your application
3125 my $rs = $schema->resultset('Artist')->search(
3126 { 'track.title' => 'Teardrop' },
3128 join => { cd => 'track' },
3129 order_by => 'artist.name',
3133 You need to use the relationship (not the table) name in conditions,
3134 because they are aliased as such. The current table is aliased as "me", so
3135 you need to use me.column_name in order to avoid ambiguity. For example:
3137 # Get CDs from 1984 with a 'Foo' track
3138 my $rs = $schema->resultset('CD')->search(
3141 'tracks.name' => 'Foo'
3143 { join => 'tracks' }
3146 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3147 similarly for a third time). For e.g.
3149 my $rs = $schema->resultset('Artist')->search({
3150 'cds.title' => 'Down to Earth',
3151 'cds_2.title' => 'Popular',
3153 join => [ qw/cds cds/ ],
3156 will return a set of all artists that have both a cd with title 'Down
3157 to Earth' and a cd with title 'Popular'.
3159 If you want to fetch related objects from other tables as well, see C<prefetch>
3162 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3168 =item Value: ($rel_name | \@rel_names | \%rel_names)
3172 Contains one or more relationships that should be fetched along with
3173 the main query (when they are accessed afterwards the data will
3174 already be available, without extra queries to the database). This is
3175 useful for when you know you will need the related objects, because it
3176 saves at least one query:
3178 my $rs = $schema->resultset('Tag')->search(
3187 The initial search results in SQL like the following:
3189 SELECT tag.*, cd.*, artist.* FROM tag
3190 JOIN cd ON tag.cd = cd.cdid
3191 JOIN artist ON cd.artist = artist.artistid
3193 L<DBIx::Class> has no need to go back to the database when we access the
3194 C<cd> or C<artist> relationships, which saves us two SQL statements in this
3197 Simple prefetches will be joined automatically, so there is no need
3198 for a C<join> attribute in the above search.
3200 C<prefetch> can be used with the following relationship types: C<belongs_to>,
3201 C<has_one> (or if you're using C<add_relationship>, any relationship declared
3202 with an accessor type of 'single' or 'filter'). A more complex example that
3203 prefetches an artists cds, the tracks on those cds, and the tags associted
3204 with that artist is given below (assuming many-to-many from artists to tags):
3206 my $rs = $schema->resultset('Artist')->search(
3210 { cds => 'tracks' },
3211 { artist_tags => 'tags' }
3217 B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
3218 attributes will be ignored.
3228 Makes the resultset paged and specifies the page to retrieve. Effectively
3229 identical to creating a non-pages resultset and then calling ->page($page)
3232 If L<rows> attribute is not specified it defaults to 10 rows per page.
3234 When you have a paged resultset, L</count> will only return the number
3235 of rows in the page. To get the total, use the L</pager> and call
3236 C<total_entries> on it.
3246 Specifes the maximum number of rows for direct retrieval or the number of
3247 rows per page if the page attribute or method is used.
3253 =item Value: $offset
3257 Specifies the (zero-based) row number for the first row to be returned, or the
3258 of the first row of the first page if paging is used.
3264 =item Value: \@columns
3268 A arrayref of columns to group by. Can include columns of joined tables.
3270 group_by => [qw/ column1 column2 ... /]
3276 =item Value: $condition
3280 HAVING is a select statement attribute that is applied between GROUP BY and
3281 ORDER BY. It is applied to the after the grouping calculations have been
3284 having => { 'count(employee)' => { '>=', 100 } }
3290 =item Value: (0 | 1)
3294 Set to 1 to group by all columns.
3300 Adds to the WHERE clause.
3302 # only return rows WHERE deleted IS NULL for all searches
3303 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
3305 Can be overridden by passing C<{ where => undef }> as an attribute
3312 Set to 1 to cache search results. This prevents extra SQL queries if you
3313 revisit rows in your ResultSet:
3315 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
3317 while( my $artist = $resultset->next ) {
3321 $rs->first; # without cache, this would issue a query
3323 By default, searches are not cached.
3325 For more examples of using these attributes, see
3326 L<DBIx::Class::Manual::Cookbook>.
3332 =item Value: \@from_clause
3336 The C<from> attribute gives you manual control over the C<FROM> clause of SQL
3337 statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
3340 NOTE: Use this on your own risk. This allows you to shoot off your foot!
3342 C<join> will usually do what you need and it is strongly recommended that you
3343 avoid using C<from> unless you cannot achieve the desired result using C<join>.
3344 And we really do mean "cannot", not just tried and failed. Attempting to use
3345 this because you're having problems with C<join> is like trying to use x86
3346 ASM because you've got a syntax error in your C. Trust us on this.
3348 Now, if you're still really, really sure you need to use this (and if you're
3349 not 100% sure, ask the mailing list first), here's an explanation of how this
3352 The syntax is as follows -
3355 { <alias1> => <table1> },
3357 { <alias2> => <table2>, -join_type => 'inner|left|right' },
3358 [], # nested JOIN (optional)
3359 { <table1.column1> => <table2.column2>, ... (more conditions) },
3361 # More of the above [ ] may follow for additional joins
3368 ON <table1.column1> = <table2.column2>
3369 <more joins may follow>
3371 An easy way to follow the examples below is to remember the following:
3373 Anything inside "[]" is a JOIN
3374 Anything inside "{}" is a condition for the enclosing JOIN
3376 The following examples utilize a "person" table in a family tree application.
3377 In order to express parent->child relationships, this table is self-joined:
3379 # Person->belongs_to('father' => 'Person');
3380 # Person->belongs_to('mother' => 'Person');
3382 C<from> can be used to nest joins. Here we return all children with a father,
3383 then search against all mothers of those children:
3385 $rs = $schema->resultset('Person')->search(
3388 alias => 'mother', # alias columns in accordance with "from"
3390 { mother => 'person' },
3393 { child => 'person' },
3395 { father => 'person' },
3396 { 'father.person_id' => 'child.father_id' }
3399 { 'mother.person_id' => 'child.mother_id' }
3406 # SELECT mother.* FROM person mother
3409 # JOIN person father
3410 # ON ( father.person_id = child.father_id )
3412 # ON ( mother.person_id = child.mother_id )
3414 The type of any join can be controlled manually. To search against only people
3415 with a father in the person table, we could explicitly use C<INNER JOIN>:
3417 $rs = $schema->resultset('Person')->search(
3420 alias => 'child', # alias columns in accordance with "from"
3422 { child => 'person' },
3424 { father => 'person', -join_type => 'inner' },
3425 { 'father.id' => 'child.father_id' }
3432 # SELECT child.* FROM person child
3433 # INNER JOIN person father ON child.father_id = father.id
3435 You can select from a subquery by passing a resultset to from as follows.
3437 $schema->resultset('Artist')->search(
3439 { alias => 'artist2',
3440 from => [ { artist2 => $artist_rs->as_query } ],
3443 # and you'll get sql like this..
3444 # SELECT artist2.artistid, artist2.name, artist2.rank, artist2.charfield FROM
3445 # ( SELECT me.artistid, me.name, me.rank, me.charfield FROM artists me ) artist2
3447 If you need to express really complex joins, you
3448 can supply literal SQL to C<from> via a scalar reference. In this case
3449 the contents of the scalar will replace the table name associated with the
3452 WARNING: This technique might very well not work as expected on chained
3453 searches - you have been warned.
3455 # Assuming the Event resultsource is defined as:
3457 MySchema::Event->add_columns (
3460 is_auto_increment => 1,
3469 MySchema::Event->set_primary_key ('sequence');
3471 # This will get back the latest event for every location. The column
3472 # selector is still provided by DBIC, all we do is add a JOIN/WHERE
3473 # combo to limit the resultset
3475 $rs = $schema->resultset('Event');
3476 $table = $rs->result_source->name;
3477 $latest = $rs->search (
3480 (SELECT e1.* FROM $table e1
3482 ON e1.location = e2.location
3483 AND e1.sequence < e2.sequence
3484 WHERE e2.sequence is NULL
3489 # Equivalent SQL (with the DBIC chunks added):
3491 SELECT me.sequence, me.location, me.type FROM
3492 (SELECT e1.* FROM events e1
3494 ON e1.location = e2.location
3495 AND e1.sequence < e2.sequence
3496 WHERE e2.sequence is NULL
3503 =item Value: ( 'update' | 'shared' )
3507 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT