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);
517 my @unique_queries = $self->_unique_queries($input_query, $attrs);
518 $query = @unique_queries
519 ? [ map { $self->_add_alias($_, $alias) } @unique_queries ]
520 : $self->_add_alias($input_query, $alias);
525 my $rs = $self->search($query, $attrs);
526 if (keys %{$rs->_resolved_attrs->{collapse}}) {
528 carp "Query returned more than one row" if $rs->next;
536 if (keys %{$self->_resolved_attrs->{collapse}}) {
537 my $rs = $self->search($query);
539 carp "Query returned more than one row" if $rs->next;
543 return $self->single($query);
550 # Add the specified alias to the specified query hash. A copy is made so the
551 # original query is not modified.
554 my ($self, $query, $alias) = @_;
556 my %aliased = %$query;
557 foreach my $col (grep { ! m/\./ } keys %aliased) {
558 $aliased{"$alias.$col"} = delete $aliased{$col};
566 # Build a list of queries which satisfy unique constraints.
568 sub _unique_queries {
569 my ($self, $query, $attrs) = @_;
571 my @constraint_names = exists $attrs->{key}
573 : $self->result_source->unique_constraint_names;
575 my $where = $self->_collapse_cond($self->{attrs}{where} || {});
576 my $num_where = scalar keys %$where;
579 foreach my $name (@constraint_names) {
580 my @unique_cols = $self->result_source->unique_constraint_columns($name);
581 my $unique_query = $self->_build_unique_query($query, \@unique_cols);
583 my $num_cols = scalar @unique_cols;
584 my $num_query = scalar keys %$unique_query;
586 my $total = $num_query + $num_where;
587 if ($num_query && ($num_query == $num_cols || $total == $num_cols)) {
588 # The query is either unique on its own or is unique in combination with
589 # the existing where clause
590 push @unique_queries, $unique_query;
594 return @unique_queries;
597 # _build_unique_query
599 # Constrain the specified query hash based on the specified column names.
601 sub _build_unique_query {
602 my ($self, $query, $unique_cols) = @_;
605 map { $_ => $query->{$_} }
606 grep { exists $query->{$_} }
611 =head2 search_related
615 =item Arguments: $rel, $cond, \%attrs?
617 =item Return Value: $new_resultset
621 $new_rs = $cd_rs->search_related('artist', {
625 Searches the specified relationship, optionally specifying a condition and
626 attributes for matching records. See L</ATTRIBUTES> for more information.
631 return shift->related_resultset(shift)->search(@_);
634 =head2 search_related_rs
636 This method works exactly the same as search_related, except that
637 it guarantees a restultset, even in list context.
641 sub search_related_rs {
642 return shift->related_resultset(shift)->search_rs(@_);
649 =item Arguments: none
651 =item Return Value: $cursor
655 Returns a storage-driven cursor to the given resultset. See
656 L<DBIx::Class::Cursor> for more information.
663 my $attrs = $self->_resolved_attrs_copy;
664 $attrs->{_virtual_order_by} = $self->_gen_virtual_order;
666 return $self->{cursor}
667 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
668 $attrs->{where},$attrs);
675 =item Arguments: $cond?
677 =item Return Value: $row_object?
681 my $cd = $schema->resultset('CD')->single({ year => 2001 });
683 Inflates the first result without creating a cursor if the resultset has
684 any records in it; if not returns nothing. Used by L</find> as a lean version of
687 While this method can take an optional search condition (just like L</search>)
688 being a fast-code-path it does not recognize search attributes. If you need to
689 add extra joins or similar, call L</search> and then chain-call L</single> on the
690 L<DBIx::Class::ResultSet> returned.
696 As of 0.08100, this method enforces the assumption that the preceeding
697 query returns only one row. If more than one row is returned, you will receive
700 Query returned more than one row
702 In this case, you should be using L</first> or L</find> instead, or if you really
703 know what you are doing, use the L</rows> attribute to explicitly limit the size
711 my ($self, $where) = @_;
713 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
716 my $attrs = $self->_resolved_attrs_copy;
717 $attrs->{_virtual_order_by} = $self->_gen_virtual_order;
720 if (defined $attrs->{where}) {
723 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
724 $where, delete $attrs->{where} ]
727 $attrs->{where} = $where;
731 # XXX: Disabled since it doesn't infer uniqueness in all cases
732 # unless ($self->_is_unique_query($attrs->{where})) {
733 # carp "Query not guaranteed to return a single row"
734 # . "; please declare your unique constraints or use search instead";
737 my @data = $self->result_source->storage->select_single(
738 $attrs->{from}, $attrs->{select},
739 $attrs->{where}, $attrs
742 return (@data ? ($self->_construct_object(@data))[0] : undef);
747 # This is a horrble hack, but seems like the best we can do at this point
748 # Some limit emulations (Top) require an ordered resultset in order to
749 # function at all. So supply a PK order if such a condition is detected
751 sub _gen_virtual_order {
753 my $attrs = $self->_resolved_attrs_copy;
755 if ($attrs->{rows} or $attrs->{offset} ) {
757 # This check requires ensure_connected, so probably cheaper to just calculate all the time
759 # my $sm = $self->result_source->storage->_sql_maker;
761 # if ($sm->_default_limit_syntax eq 'Top' and not @{$sm->_resolve_order ($attrs->{order_by}) }) {
763 return [ $self->result_source->primary_columns ];
773 # Try to determine if the specified query is guaranteed to be unique, based on
774 # the declared unique constraints.
776 sub _is_unique_query {
777 my ($self, $query) = @_;
779 my $collapsed = $self->_collapse_query($query);
780 my $alias = $self->{attrs}{alias};
782 foreach my $name ($self->result_source->unique_constraint_names) {
783 my @unique_cols = map {
785 } $self->result_source->unique_constraint_columns($name);
787 # Count the values for each unique column
788 my %seen = map { $_ => 0 } @unique_cols;
790 foreach my $key (keys %$collapsed) {
791 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
792 next unless exists $seen{$aliased}; # Additional constraints are okay
793 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
796 # If we get 0 or more than 1 value for a column, it's not necessarily unique
797 return 1 unless grep { $_ != 1 } values %seen;
805 # Recursively collapse the query, accumulating values for each column.
807 sub _collapse_query {
808 my ($self, $query, $collapsed) = @_;
812 if (ref $query eq 'ARRAY') {
813 foreach my $subquery (@$query) {
814 next unless ref $subquery; # -or
815 $collapsed = $self->_collapse_query($subquery, $collapsed);
818 elsif (ref $query eq 'HASH') {
819 if (keys %$query and (keys %$query)[0] eq '-and') {
820 foreach my $subquery (@{$query->{-and}}) {
821 $collapsed = $self->_collapse_query($subquery, $collapsed);
825 foreach my $col (keys %$query) {
826 my $value = $query->{$col};
827 $collapsed->{$col}{$value}++;
839 =item Arguments: $cond?
841 =item Return Value: $resultsetcolumn
845 my $max_length = $rs->get_column('length')->max;
847 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
852 my ($self, $column) = @_;
853 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
861 =item Arguments: $cond, \%attrs?
863 =item Return Value: $resultset (scalar context), @row_objs (list context)
867 # WHERE title LIKE '%blue%'
868 $cd_rs = $rs->search_like({ title => '%blue%'});
870 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
871 that this is simply a convenience method retained for ex Class::DBI users.
872 You most likely want to use L</search> with specific operators.
874 For more information, see L<DBIx::Class::Manual::Cookbook>.
876 This method is deprecated and will be removed in 0.09. Use L</search()>
877 instead. An example conversion is:
879 ->search_like({ foo => 'bar' });
883 ->search({ foo => { like => 'bar' } });
890 'search_like() is deprecated and will be removed in DBIC version 0.09.'
891 .' Instead use ->search({ x => { -like => "y%" } })'
892 .' (note the outer pair of {}s - they are important!)'
894 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
895 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
896 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
897 return $class->search($query, { %$attrs });
904 =item Arguments: $first, $last
906 =item Return Value: $resultset (scalar context), @row_objs (list context)
910 Returns a resultset or object list representing a subset of elements from the
911 resultset slice is called on. Indexes are from 0, i.e., to get the first
914 my ($one, $two, $three) = $rs->slice(0, 2);
919 my ($self, $min, $max) = @_;
920 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
921 $attrs->{offset} = $self->{attrs}{offset} || 0;
922 $attrs->{offset} += $min;
923 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
924 return $self->search(undef(), $attrs);
925 #my $slice = (ref $self)->new($self->result_source, $attrs);
926 #return (wantarray ? $slice->all : $slice);
933 =item Arguments: none
935 =item Return Value: $result?
939 Returns the next element in the resultset (C<undef> is there is none).
941 Can be used to efficiently iterate over records in the resultset:
943 my $rs = $schema->resultset('CD')->search;
944 while (my $cd = $rs->next) {
948 Note that you need to store the resultset object, and call C<next> on it.
949 Calling C<< resultset('Table')->next >> repeatedly will always return the
950 first record from the resultset.
956 if (my $cache = $self->get_cache) {
957 $self->{all_cache_position} ||= 0;
958 return $cache->[$self->{all_cache_position}++];
960 if ($self->{attrs}{cache}) {
961 $self->{all_cache_position} = 1;
962 return ($self->all)[0];
964 if ($self->{stashed_objects}) {
965 my $obj = shift(@{$self->{stashed_objects}});
966 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
970 exists $self->{stashed_row}
971 ? @{delete $self->{stashed_row}}
972 : $self->cursor->next
974 return undef unless (@row);
975 my ($row, @more) = $self->_construct_object(@row);
976 $self->{stashed_objects} = \@more if @more;
980 sub _construct_object {
981 my ($self, @row) = @_;
982 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row);
983 my @new = $self->result_class->inflate_result($self->result_source, @$info);
984 @new = $self->{_attrs}{record_filter}->(@new)
985 if exists $self->{_attrs}{record_filter};
989 sub _collapse_result {
990 my ($self, $as_proto, $row) = @_;
994 # 'foo' => [ undef, 'foo' ]
995 # 'foo.bar' => [ 'foo', 'bar' ]
996 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
998 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
1000 my %collapse = %{$self->{_attrs}{collapse}||{}};
1004 # if we're doing collapsing (has_many prefetch) we need to grab records
1005 # until the PK changes, so fill @pri_index. if not, we leave it empty so
1006 # we know we don't have to bother.
1008 # the reason for not using the collapse stuff directly is because if you
1009 # had for e.g. two artists in a row with no cds, the collapse info for
1010 # both would be NULL (undef) so you'd lose the second artist
1012 # store just the index so we can check the array positions from the row
1013 # without having to contruct the full hash
1015 if (keys %collapse) {
1016 my %pri = map { ($_ => 1) } $self->result_source->primary_columns;
1017 foreach my $i (0 .. $#construct_as) {
1018 next if defined($construct_as[$i][0]); # only self table
1019 if (delete $pri{$construct_as[$i][1]}) {
1020 push(@pri_index, $i);
1022 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
1026 # no need to do an if, it'll be empty if @pri_index is empty anyway
1028 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
1032 do { # no need to check anything at the front, we always want the first row
1036 foreach my $this_as (@construct_as) {
1037 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
1040 push(@const_rows, \%const);
1042 } until ( # no pri_index => no collapse => drop straight out
1045 do { # get another row, stash it, drop out if different PK
1047 @copy = $self->cursor->next;
1048 $self->{stashed_row} = \@copy;
1050 # last thing in do block, counts as true if anything doesn't match
1052 # check xor defined first for NULL vs. NOT NULL then if one is
1053 # defined the other must be so check string equality
1056 (defined $pri_vals{$_} ^ defined $copy[$_])
1057 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
1062 my $alias = $self->{attrs}{alias};
1069 foreach my $const (@const_rows) {
1070 scalar @const_keys or do {
1071 @const_keys = sort { length($a) <=> length($b) } keys %$const;
1073 foreach my $key (@const_keys) {
1076 my @parts = split(/\./, $key);
1078 my $data = $const->{$key};
1079 foreach my $p (@parts) {
1080 $target = $target->[1]->{$p} ||= [];
1082 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
1083 # collapsing at this point and on final part
1084 my $pos = $collapse_pos{$cur};
1085 CK: foreach my $ck (@ckey) {
1086 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
1087 $collapse_pos{$cur} = $data;
1088 delete @collapse_pos{ # clear all positioning for sub-entries
1089 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
1096 if (exists $collapse{$cur}) {
1097 $target = $target->[-1];
1100 $target->[0] = $data;
1102 $info->[0] = $const->{$key};
1110 =head2 result_source
1114 =item Arguments: $result_source?
1116 =item Return Value: $result_source
1120 An accessor for the primary ResultSource object from which this ResultSet
1127 =item Arguments: $result_class?
1129 =item Return Value: $result_class
1133 An accessor for the class to use when creating row objects. Defaults to
1134 C<< result_source->result_class >> - which in most cases is the name of the
1135 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1137 Note that changing the result_class will also remove any components
1138 that were originally loaded in the source class via
1139 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1140 in the original source class will not run.
1145 my ($self, $result_class) = @_;
1146 if ($result_class) {
1147 $self->ensure_class_loaded($result_class);
1148 $self->_result_class($result_class);
1150 $self->_result_class;
1157 =item Arguments: $cond, \%attrs??
1159 =item Return Value: $count
1163 Performs an SQL C<COUNT> with the same query as the resultset was built
1164 with to find the number of elements. Passing arguments is equivalent to
1165 C<< $rs->search ($cond, \%attrs)->count >>
1171 return $self->search(@_)->count if @_ and defined $_[0];
1172 return scalar @{ $self->get_cache } if $self->get_cache;
1174 my @grouped_subq_attrs = qw/prefetch collapse distinct group_by having/;
1175 my @subq_attrs = ();
1177 my $attrs = $self->_resolved_attrs;
1178 # if we are not paged - we are simply asking for a limit
1179 if (not $attrs->{page} and not $attrs->{software_limit}) {
1180 push @subq_attrs, qw/rows offset/;
1183 my $need_subq = $self->_has_attr (@subq_attrs);
1184 my $need_group_subq = $self->_has_attr (@grouped_subq_attrs);
1186 return ($need_subq || $need_group_subq)
1187 ? $self->_count_subq ($need_group_subq)
1188 : $self->_count_simple
1192 my ($self, $add_group_by) = @_;
1194 my $attrs = $self->_resolved_attrs_copy;
1196 # copy for the subquery, we need to do some adjustments to it too
1197 my $sub_attrs = { %$attrs };
1199 # these can not go in the subquery, and there is no point of ordering it
1200 delete $sub_attrs->{$_} for qw/prefetch collapse select +select as +as columns +columns order_by/;
1202 # if needed force a group_by and the same set of columns (most databases require this)
1203 if ($add_group_by) {
1205 # if we prefetch, we group_by primary keys only as this is what we would get out of the rs via ->next/->all
1206 # simply deleting group_by suffices, as the code below will re-fill it
1207 # Note: we check $attrs, as $sub_attrs has collapse deleted
1208 if (ref $attrs->{collapse} and keys %{$attrs->{collapse}} ) {
1209 delete $sub_attrs->{group_by};
1212 $sub_attrs->{columns} = $sub_attrs->{group_by} ||= [ map { "$attrs->{alias}.$_" } ($self->result_source->primary_columns) ];
1216 count_subq => (ref $self)->new ($self->result_source, $sub_attrs )->as_query
1219 # the subquery replaces this
1220 delete $attrs->{$_} for qw/where bind prefetch collapse distinct group_by having having_bind/;
1222 return $self->__count ($attrs);
1228 my $count = $self->__count;
1229 return 0 unless $count;
1231 # need to take offset from resolved attrs
1233 my $attrs = $self->_resolved_attrs;
1235 $count -= $attrs->{offset} if $attrs->{offset};
1236 $count = $attrs->{rows} if $attrs->{rows} and $attrs->{rows} < $count;
1237 $count = 0 if ($count < 0);
1242 my ($self, $attrs) = @_;
1244 $attrs ||= $self->_resolved_attrs_copy;
1246 # take off any column specs, any pagers, record_filter is cdbi, and no point of ordering a count
1247 delete $attrs->{$_} for (qw/columns +columns select +select as +as rows offset page pager order_by record_filter/);
1249 $attrs->{select} = { count => '*' };
1250 $attrs->{as} = [qw/count/];
1252 my $tmp_rs = (ref $self)->new($self->result_source, $attrs);
1253 my ($count) = $tmp_rs->cursor->next;
1262 =head2 count_literal
1266 =item Arguments: $sql_fragment, @bind_values
1268 =item Return Value: $count
1272 Counts the results in a literal query. Equivalent to calling L</search_literal>
1273 with the passed arguments, then L</count>.
1277 sub count_literal { shift->search_literal(@_)->count; }
1283 =item Arguments: none
1285 =item Return Value: @objects
1289 Returns all elements in the resultset. Called implicitly if the resultset
1290 is returned in list context.
1297 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1300 return @{ $self->get_cache } if $self->get_cache;
1304 # TODO: don't call resolve here
1305 if (keys %{$self->_resolved_attrs->{collapse}}) {
1306 # if ($self->{attrs}{prefetch}) {
1307 # Using $self->cursor->all is really just an optimisation.
1308 # If we're collapsing has_many prefetches it probably makes
1309 # very little difference, and this is cleaner than hacking
1310 # _construct_object to survive the approach
1311 my @row = $self->cursor->next;
1313 push(@obj, $self->_construct_object(@row));
1314 @row = (exists $self->{stashed_row}
1315 ? @{delete $self->{stashed_row}}
1316 : $self->cursor->next);
1319 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1322 $self->set_cache(\@obj) if $self->{attrs}{cache};
1330 =item Arguments: none
1332 =item Return Value: $self
1336 Resets the resultset's cursor, so you can iterate through the elements again.
1342 delete $self->{_attrs} if exists $self->{_attrs};
1343 $self->{all_cache_position} = 0;
1344 $self->cursor->reset;
1352 =item Arguments: none
1354 =item Return Value: $object?
1358 Resets the resultset and returns an object for the first result (if the
1359 resultset returns anything).
1364 return $_[0]->reset->next;
1370 # Determines whether and what type of subquery is required for the $rs operation.
1371 # If grouping is necessary either supplies its own, or verifies the current one
1372 # After all is done delegates to the proper storage method.
1374 sub _rs_update_delete {
1375 my ($self, $op, $values) = @_;
1377 my $rsrc = $self->result_source;
1379 my $needs_group_by_subq = $self->_has_attr (qw/prefetch distinct join seen_join group_by/);
1380 my $needs_subq = $self->_has_attr (qw/row offset page/);
1382 if ($needs_group_by_subq or $needs_subq) {
1384 # make a new $rs selecting only the PKs (that's all we really need)
1385 my $attrs = $self->_resolved_attrs_copy;
1387 delete $attrs->{$_} for qw/prefetch collapse select +select as +as columns +columns/;
1388 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->primary_columns) ];
1390 if ($needs_group_by_subq) {
1391 # make sure no group_by was supplied, or if there is one - make sure it matches
1392 # the columns compiled above perfectly. Anything else can not be sanely executed
1393 # on most databases so croak right then and there
1395 if (my $g = $attrs->{group_by}) {
1396 my @current_group_by = map
1397 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1398 (ref $g eq 'ARRAY' ? @$g : $g );
1401 join ("\x00", sort @current_group_by)
1403 join ("\x00", sort @{$attrs->{columns}} )
1405 $self->throw_exception (
1406 "You have just attempted a $op operation on a resultset which does group_by"
1407 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1408 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1409 . ' kind of queries. Please retry the operation with a modified group_by or'
1410 . ' without using one at all.'
1415 $attrs->{group_by} = $attrs->{columns};
1419 my $subrs = (ref $self)->new($rsrc, $attrs);
1421 return $self->result_source->storage->subq_update_delete($subrs, $op, $values);
1424 return $rsrc->storage->$op(
1426 $op eq 'update' ? $values : (),
1427 $self->_cond_for_update_delete,
1433 # _cond_for_update_delete
1435 # update/delete require the condition to be modified to handle
1436 # the differing SQL syntax available. This transforms the $self->{cond}
1437 # appropriately, returning the new condition.
1439 sub _cond_for_update_delete {
1440 my ($self, $full_cond) = @_;
1443 $full_cond ||= $self->{cond};
1444 # No-op. No condition, we're updating/deleting everything
1445 return $cond unless ref $full_cond;
1447 if (ref $full_cond eq 'ARRAY') {
1451 foreach my $key (keys %{$_}) {
1453 $hash{$1} = $_->{$key};
1459 elsif (ref $full_cond eq 'HASH') {
1460 if ((keys %{$full_cond})[0] eq '-and') {
1462 my @cond = @{$full_cond->{-and}};
1463 for (my $i = 0; $i < @cond; $i++) {
1464 my $entry = $cond[$i];
1466 if (ref $entry eq 'HASH') {
1467 $hash = $self->_cond_for_update_delete($entry);
1470 $entry =~ /([^.]+)$/;
1471 $hash->{$1} = $cond[++$i];
1473 push @{$cond->{-and}}, $hash;
1477 foreach my $key (keys %{$full_cond}) {
1479 $cond->{$1} = $full_cond->{$key};
1484 $self->throw_exception("Can't update/delete on resultset with condition unless hash or array");
1495 =item Arguments: \%values
1497 =item Return Value: $storage_rv
1501 Sets the specified columns in the resultset to the supplied values in a
1502 single query. Return value will be true if the update succeeded or false
1503 if no records were updated; exact type of success value is storage-dependent.
1508 my ($self, $values) = @_;
1509 $self->throw_exception('Values for update must be a hash')
1510 unless ref $values eq 'HASH';
1512 return $self->_rs_update_delete ('update', $values);
1519 =item Arguments: \%values
1521 =item Return Value: 1
1525 Fetches all objects and updates them one at a time. Note that C<update_all>
1526 will run DBIC cascade triggers, while L</update> will not.
1531 my ($self, $values) = @_;
1532 $self->throw_exception('Values for update_all must be a hash')
1533 unless ref $values eq 'HASH';
1534 foreach my $obj ($self->all) {
1535 $obj->set_columns($values)->update;
1544 =item Arguments: none
1546 =item Return Value: 1
1550 Deletes the contents of the resultset from its result source. Note that this
1551 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1552 to run. See also L<DBIx::Class::Row/delete>.
1554 delete may not generate correct SQL for a query with joins or a resultset
1555 chained from a related resultset. In this case it will generate a warning:-
1557 In these cases you may find that delete_all is more appropriate, or you
1558 need to respecify your query in a way that can be expressed without a join.
1564 $self->throw_exception('delete does not accept any arguments')
1567 return $self->_rs_update_delete ('delete');
1574 =item Arguments: none
1576 =item Return Value: 1
1580 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1581 will run DBIC cascade triggers, while L</delete> will not.
1587 $self->throw_exception('delete_all does not accept any arguments')
1590 $_->delete for $self->all;
1598 =item Arguments: \@data;
1602 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1603 For the arrayref of hashrefs style each hashref should be a structure suitable
1604 forsubmitting to a $resultset->create(...) method.
1606 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1607 to insert the data, as this is a faster method.
1609 Otherwise, each set of data is inserted into the database using
1610 L<DBIx::Class::ResultSet/create>, and a arrayref of the resulting row
1611 objects is returned.
1613 Example: Assuming an Artist Class that has many CDs Classes relating:
1615 my $Artist_rs = $schema->resultset("Artist");
1617 ## Void Context Example
1618 $Artist_rs->populate([
1619 { artistid => 4, name => 'Manufactured Crap', cds => [
1620 { title => 'My First CD', year => 2006 },
1621 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1624 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1625 { title => 'My parents sold me to a record company' ,year => 2005 },
1626 { title => 'Why Am I So Ugly?', year => 2006 },
1627 { title => 'I Got Surgery and am now Popular', year => 2007 }
1632 ## Array Context Example
1633 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1634 { name => "Artist One"},
1635 { name => "Artist Two"},
1636 { name => "Artist Three", cds=> [
1637 { title => "First CD", year => 2007},
1638 { title => "Second CD", year => 2008},
1642 print $ArtistOne->name; ## response is 'Artist One'
1643 print $ArtistThree->cds->count ## reponse is '2'
1645 For the arrayref of arrayrefs style, the first element should be a list of the
1646 fieldsnames to which the remaining elements are rows being inserted. For
1649 $Arstist_rs->populate([
1650 [qw/artistid name/],
1651 [100, 'A Formally Unknown Singer'],
1652 [101, 'A singer that jumped the shark two albums ago'],
1653 [102, 'An actually cool singer.'],
1656 Please note an important effect on your data when choosing between void and
1657 wantarray context. Since void context goes straight to C<insert_bulk> in
1658 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
1659 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
1660 create primary keys for you, you will find that your PKs are empty. In this
1661 case you will have to use the wantarray context in order to create those
1667 my $self = shift @_;
1668 my $data = ref $_[0][0] eq 'HASH'
1669 ? $_[0] : ref $_[0][0] eq 'ARRAY' ? $self->_normalize_populate_args($_[0]) :
1670 $self->throw_exception('Populate expects an arrayref of hashes or arrayref of arrayrefs');
1672 if(defined wantarray) {
1674 foreach my $item (@$data) {
1675 push(@created, $self->create($item));
1679 my ($first, @rest) = @$data;
1681 my @names = grep {!ref $first->{$_}} keys %$first;
1682 my @rels = grep { $self->result_source->has_relationship($_) } keys %$first;
1683 my @pks = $self->result_source->primary_columns;
1685 ## do the belongs_to relationships
1686 foreach my $index (0..$#$data) {
1687 if( grep { !defined $data->[$index]->{$_} } @pks ) {
1688 my @ret = $self->populate($data);
1692 foreach my $rel (@rels) {
1693 next unless $data->[$index]->{$rel} && ref $data->[$index]->{$rel} eq "HASH";
1694 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1695 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1696 my $related = $result->result_source->_resolve_condition(
1697 $result->result_source->relationship_info($reverse)->{cond},
1702 delete $data->[$index]->{$rel};
1703 $data->[$index] = {%{$data->[$index]}, %$related};
1705 push @names, keys %$related if $index == 0;
1709 ## do bulk insert on current row
1710 my @values = map { [ @$_{@names} ] } @$data;
1712 $self->result_source->storage->insert_bulk(
1713 $self->result_source,
1718 ## do the has_many relationships
1719 foreach my $item (@$data) {
1721 foreach my $rel (@rels) {
1722 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1724 my $parent = $self->find(map {{$_=>$item->{$_}} } @pks)
1725 || $self->throw_exception('Cannot find the relating object.');
1727 my $child = $parent->$rel;
1729 my $related = $child->result_source->_resolve_condition(
1730 $parent->result_source->relationship_info($rel)->{cond},
1735 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1736 my @populate = map { {%$_, %$related} } @rows_to_add;
1738 $child->populate( \@populate );
1744 =head2 _normalize_populate_args ($args)
1746 Private method used by L</populate> to normalize its incoming arguments. Factored
1747 out in case you want to subclass and accept new argument structures to the
1748 L</populate> method.
1752 sub _normalize_populate_args {
1753 my ($self, $data) = @_;
1754 my @names = @{shift(@$data)};
1755 my @results_to_create;
1756 foreach my $datum (@$data) {
1757 my %result_to_create;
1758 foreach my $index (0..$#names) {
1759 $result_to_create{$names[$index]} = $$datum[$index];
1761 push @results_to_create, \%result_to_create;
1763 return \@results_to_create;
1770 =item Arguments: none
1772 =item Return Value: $pager
1776 Return Value a L<Data::Page> object for the current resultset. Only makes
1777 sense for queries with a C<page> attribute.
1779 To get the full count of entries for a paged resultset, call
1780 C<total_entries> on the L<Data::Page> object.
1787 return $self->{pager} if $self->{pager};
1789 my $attrs = $self->{attrs};
1790 $self->throw_exception("Can't create pager for non-paged rs")
1791 unless $self->{attrs}{page};
1792 $attrs->{rows} ||= 10;
1794 # throw away the paging flags and re-run the count (possibly
1795 # with a subselect) to get the real total count
1796 my $count_attrs = { %$attrs };
1797 delete $count_attrs->{$_} for qw/rows offset page pager/;
1798 my $total_count = (ref $self)->new($self->result_source, $count_attrs)->count;
1800 return $self->{pager} = Data::Page->new(
1803 $self->{attrs}{page}
1811 =item Arguments: $page_number
1813 =item Return Value: $rs
1817 Returns a resultset for the $page_number page of the resultset on which page
1818 is called, where each page contains a number of rows equal to the 'rows'
1819 attribute set on the resultset (10 by default).
1824 my ($self, $page) = @_;
1825 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1832 =item Arguments: \%vals
1834 =item Return Value: $rowobject
1838 Creates a new row object in the resultset's result class and returns
1839 it. The row is not inserted into the database at this point, call
1840 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
1841 will tell you whether the row object has been inserted or not.
1843 Passes the hashref of input on to L<DBIx::Class::Row/new>.
1848 my ($self, $values) = @_;
1849 $self->throw_exception( "new_result needs a hash" )
1850 unless (ref $values eq 'HASH');
1853 my $alias = $self->{attrs}{alias};
1856 defined $self->{cond}
1857 && $self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION
1859 %new = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
1860 $new{-from_resultset} = [ keys %new ] if keys %new;
1862 $self->throw_exception(
1863 "Can't abstract implicit construct, condition not a hash"
1864 ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
1866 my $collapsed_cond = (
1868 ? $self->_collapse_cond($self->{cond})
1872 # precendence must be given to passed values over values inherited from
1873 # the cond, so the order here is important.
1874 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
1875 while( my($col,$value) = each %implied ){
1876 if(ref($value) eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '='){
1877 $new{$col} = $value->{'='};
1880 $new{$col} = $value if $self->_is_deterministic_value($value);
1886 %{ $self->_remove_alias($values, $alias) },
1887 -source_handle => $self->_source_handle,
1888 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
1891 return $self->result_class->new(\%new);
1894 # _is_deterministic_value
1896 # Make an effor to strip non-deterministic values from the condition,
1897 # to make sure new_result chokes less
1899 sub _is_deterministic_value {
1902 my $ref_type = ref $value;
1903 return 1 if $ref_type eq '' || $ref_type eq 'SCALAR';
1904 return 1 if Scalar::Util::blessed($value);
1910 # determines if the resultset defines at least one
1911 # of the attributes supplied
1913 # used to determine if a subquery is neccessary
1916 my ($self, @attr_names) = @_;
1918 my $attrs = $self->_resolved_attrs;
1922 for my $n (@attr_names) {
1923 ++$join_check_req if $n =~ /join/;
1925 my $attr = $attrs->{$n};
1927 next if not defined $attr;
1929 if (ref $attr eq 'HASH') {
1930 return 1 if keys %$attr;
1932 elsif (ref $attr eq 'ARRAY') {
1940 # a join can be expressed as a multi-level from
1944 ref $attrs->{from} eq 'ARRAY'
1946 @{$attrs->{from}} > 1
1954 # Recursively collapse the condition.
1956 sub _collapse_cond {
1957 my ($self, $cond, $collapsed) = @_;
1961 if (ref $cond eq 'ARRAY') {
1962 foreach my $subcond (@$cond) {
1963 next unless ref $subcond; # -or
1964 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1967 elsif (ref $cond eq 'HASH') {
1968 if (keys %$cond and (keys %$cond)[0] eq '-and') {
1969 foreach my $subcond (@{$cond->{-and}}) {
1970 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1974 foreach my $col (keys %$cond) {
1975 my $value = $cond->{$col};
1976 $collapsed->{$col} = $value;
1986 # Remove the specified alias from the specified query hash. A copy is made so
1987 # the original query is not modified.
1990 my ($self, $query, $alias) = @_;
1992 my %orig = %{ $query || {} };
1995 foreach my $key (keys %orig) {
1997 $unaliased{$key} = $orig{$key};
2000 $unaliased{$1} = $orig{$key}
2001 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2007 =head2 as_query (EXPERIMENTAL)
2011 =item Arguments: none
2013 =item Return Value: \[ $sql, @bind ]
2017 Returns the SQL query and bind vars associated with the invocant.
2019 This is generally used as the RHS for a subquery.
2021 B<NOTE>: This feature is still experimental.
2025 sub as_query { return shift->cursor->as_query(@_) }
2031 =item Arguments: \%vals, \%attrs?
2033 =item Return Value: $rowobject
2037 my $artist = $schema->resultset('Artist')->find_or_new(
2038 { artist => 'fred' }, { key => 'artists' });
2040 $cd->cd_to_producer->find_or_new({ producer => $producer },
2041 { key => 'primary });
2043 Find an existing record from this resultset, based on its primary
2044 key, or a unique constraint. If none exists, instantiate a new result
2045 object and return it. The object will not be saved into your storage
2046 until you call L<DBIx::Class::Row/insert> on it.
2048 You most likely want this method when looking for existing rows using
2049 a unique constraint that is not the primary key, or looking for
2052 If you want objects to be saved immediately, use L</find_or_create> instead.
2054 B<Note>: C<find_or_new> is probably not what you want when creating a
2055 new row in a table that uses primary keys supplied by the
2056 database. Passing in a primary key column with a value of I<undef>
2057 will cause L</find> to attempt to search for a row with a value of
2064 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2065 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2066 my $exists = $self->find($hash, $attrs);
2067 return defined $exists ? $exists : $self->new_result($hash);
2074 =item Arguments: \%vals
2076 =item Return Value: a L<DBIx::Class::Row> $object
2080 Attempt to create a single new row or a row with multiple related rows
2081 in the table represented by the resultset (and related tables). This
2082 will not check for duplicate rows before inserting, use
2083 L</find_or_create> to do that.
2085 To create one row for this resultset, pass a hashref of key/value
2086 pairs representing the columns of the table and the values you wish to
2087 store. If the appropriate relationships are set up, foreign key fields
2088 can also be passed an object representing the foreign row, and the
2089 value will be set to its primary key.
2091 To create related objects, pass a hashref for the value if the related
2092 item is a foreign key relationship (L<DBIx::Class::Relationship/belongs_to>),
2093 and use the name of the relationship as the key. (NOT the name of the field,
2094 necessarily). For C<has_many> and C<has_one> relationships, pass an arrayref
2095 of hashrefs containing the data for each of the rows to create in the foreign
2096 tables, again using the relationship name as the key.
2098 Instead of hashrefs of plain related data (key/value pairs), you may
2099 also pass new or inserted objects. New objects (not inserted yet, see
2100 L</new>), will be inserted into their appropriate tables.
2102 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2104 Example of creating a new row.
2106 $person_rs->create({
2107 name=>"Some Person",
2108 email=>"somebody@someplace.com"
2111 Example of creating a new row and also creating rows in a related C<has_many>
2112 or C<has_one> resultset. Note Arrayref.
2115 { artistid => 4, name => 'Manufactured Crap', cds => [
2116 { title => 'My First CD', year => 2006 },
2117 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2122 Example of creating a new row and also creating a row in a related
2123 C<belongs_to>resultset. Note Hashref.
2126 title=>"Music for Silly Walks",
2129 name=>"Silly Musician",
2136 my ($self, $attrs) = @_;
2137 $self->throw_exception( "create needs a hashref" )
2138 unless ref $attrs eq 'HASH';
2139 return $self->new_result($attrs)->insert;
2142 =head2 find_or_create
2146 =item Arguments: \%vals, \%attrs?
2148 =item Return Value: $rowobject
2152 $cd->cd_to_producer->find_or_create({ producer => $producer },
2153 { key => 'primary });
2155 Tries to find a record based on its primary key or unique constraints; if none
2156 is found, creates one and returns that instead.
2158 my $cd = $schema->resultset('CD')->find_or_create({
2160 artist => 'Massive Attack',
2161 title => 'Mezzanine',
2165 Also takes an optional C<key> attribute, to search by a specific key or unique
2166 constraint. For example:
2168 my $cd = $schema->resultset('CD')->find_or_create(
2170 artist => 'Massive Attack',
2171 title => 'Mezzanine',
2173 { key => 'cd_artist_title' }
2176 B<Note>: Because find_or_create() reads from the database and then
2177 possibly inserts based on the result, this method is subject to a race
2178 condition. Another process could create a record in the table after
2179 the find has completed and before the create has started. To avoid
2180 this problem, use find_or_create() inside a transaction.
2182 B<Note>: C<find_or_create> is probably not what you want when creating
2183 a new row in a table that uses primary keys supplied by the
2184 database. Passing in a primary key column with a value of I<undef>
2185 will cause L</find> to attempt to search for a row with a value of
2188 See also L</find> and L</update_or_create>. For information on how to declare
2189 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2193 sub find_or_create {
2195 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2196 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2197 my $exists = $self->find($hash, $attrs);
2198 return defined $exists ? $exists : $self->create($hash);
2201 =head2 update_or_create
2205 =item Arguments: \%col_values, { key => $unique_constraint }?
2207 =item Return Value: $rowobject
2211 $resultset->update_or_create({ col => $val, ... });
2213 First, searches for an existing row matching one of the unique constraints
2214 (including the primary key) on the source of this resultset. If a row is
2215 found, updates it with the other given column values. Otherwise, creates a new
2218 Takes an optional C<key> attribute to search on a specific unique constraint.
2221 # In your application
2222 my $cd = $schema->resultset('CD')->update_or_create(
2224 artist => 'Massive Attack',
2225 title => 'Mezzanine',
2228 { key => 'cd_artist_title' }
2231 $cd->cd_to_producer->update_or_create({
2232 producer => $producer,
2239 If no C<key> is specified, it searches on all unique constraints defined on the
2240 source, including the primary key.
2242 If the C<key> is specified as C<primary>, it searches only on the primary key.
2244 See also L</find> and L</find_or_create>. For information on how to declare
2245 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2247 B<Note>: C<update_or_create> is probably not what you want when
2248 looking for a row in a table that uses primary keys supplied by the
2249 database, unless you actually have a key value. Passing in a primary
2250 key column with a value of I<undef> will cause L</find> to attempt to
2251 search for a row with a value of I<NULL>.
2255 sub update_or_create {
2257 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2258 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2260 my $row = $self->find($cond, $attrs);
2262 $row->update($cond);
2266 return $self->create($cond);
2269 =head2 update_or_new
2273 =item Arguments: \%col_values, { key => $unique_constraint }?
2275 =item Return Value: $rowobject
2279 $resultset->update_or_new({ col => $val, ... });
2281 First, searches for an existing row matching one of the unique constraints
2282 (including the primary key) on the source of this resultset. If a row is
2283 found, updates it with the other given column values. Otherwise, instantiate
2284 a new result object and return it. The object will not be saved into your storage
2285 until you call L<DBIx::Class::Row/insert> on it.
2287 Takes an optional C<key> attribute to search on a specific unique constraint.
2290 # In your application
2291 my $cd = $schema->resultset('CD')->update_or_new(
2293 artist => 'Massive Attack',
2294 title => 'Mezzanine',
2297 { key => 'cd_artist_title' }
2300 if ($cd->in_storage) {
2301 # the cd was updated
2304 # the cd is not yet in the database, let's insert it
2308 See also L</find>, L</find_or_create> and L<find_or_new>.
2314 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2315 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2317 my $row = $self->find( $cond, $attrs );
2318 if ( defined $row ) {
2319 $row->update($cond);
2323 return $self->new_result($cond);
2330 =item Arguments: none
2332 =item Return Value: \@cache_objects?
2336 Gets the contents of the cache for the resultset, if the cache is set.
2338 The cache is populated either by using the L</prefetch> attribute to
2339 L</search> or by calling L</set_cache>.
2351 =item Arguments: \@cache_objects
2353 =item Return Value: \@cache_objects
2357 Sets the contents of the cache for the resultset. Expects an arrayref
2358 of objects of the same class as those produced by the resultset. Note that
2359 if the cache is set the resultset will return the cached objects rather
2360 than re-querying the database even if the cache attr is not set.
2362 The contents of the cache can also be populated by using the
2363 L</prefetch> attribute to L</search>.
2368 my ( $self, $data ) = @_;
2369 $self->throw_exception("set_cache requires an arrayref")
2370 if defined($data) && (ref $data ne 'ARRAY');
2371 $self->{all_cache} = $data;
2378 =item Arguments: none
2380 =item Return Value: []
2384 Clears the cache for the resultset.
2389 shift->set_cache(undef);
2392 =head2 related_resultset
2396 =item Arguments: $relationship_name
2398 =item Return Value: $resultset
2402 Returns a related resultset for the supplied relationship name.
2404 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2408 sub related_resultset {
2409 my ($self, $rel) = @_;
2411 $self->{related_resultsets} ||= {};
2412 return $self->{related_resultsets}{$rel} ||= do {
2413 my $rel_obj = $self->result_source->relationship_info($rel);
2415 $self->throw_exception(
2416 "search_related: result source '" . $self->result_source->source_name .
2417 "' has no such relationship $rel")
2420 my ($from,$seen) = $self->_resolve_from($rel);
2422 my $join_count = $seen->{$rel};
2423 my $alias = ($join_count > 1 ? join('_', $rel, $join_count) : $rel);
2425 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2426 my %attrs = %{$self->{attrs}||{}};
2427 delete @attrs{qw(result_class alias)};
2431 if (my $cache = $self->get_cache) {
2432 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2433 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
2438 my $rel_source = $self->result_source->related_source($rel);
2442 # The reason we do this now instead of passing the alias to the
2443 # search_rs below is that if you wrap/overload resultset on the
2444 # source you need to know what alias it's -going- to have for things
2445 # to work sanely (e.g. RestrictWithObject wants to be able to add
2446 # extra query restrictions, and these may need to be $alias.)
2448 my $attrs = $rel_source->resultset_attributes;
2449 local $attrs->{alias} = $alias;
2451 $rel_source->resultset
2459 where => $self->{cond},
2464 $new->set_cache($new_cache) if $new_cache;
2469 =head2 current_source_alias
2473 =item Arguments: none
2475 =item Return Value: $source_alias
2479 Returns the current table alias for the result source this resultset is built
2480 on, that will be used in the SQL query. Usually it is C<me>.
2482 Currently the source alias that refers to the result set returned by a
2483 L</search>/L</find> family method depends on how you got to the resultset: it's
2484 C<me> by default, but eg. L</search_related> aliases it to the related result
2485 source name (and keeps C<me> referring to the original result set). The long
2486 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
2487 (and make this method unnecessary).
2489 Thus it's currently necessary to use this method in predefined queries (see
2490 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
2491 source alias of the current result set:
2493 # in a result set class
2495 my ($self, $user) = @_;
2497 my $me = $self->current_source_alias;
2499 return $self->search(
2500 "$me.modified" => $user->id,
2506 sub current_source_alias {
2509 return ($self->{attrs} || {})->{alias} || 'me';
2512 # This code is called by search_related, and makes sure there
2513 # is clear separation between the joins before, during, and
2514 # after the relationship. This information is needed later
2515 # in order to properly resolve prefetch aliases (any alias
2516 # with a relation_chain_depth less than the depth of the
2517 # current prefetch is not considered)
2519 my ($self, $extra_join) = @_;
2520 my $source = $self->result_source;
2521 my $attrs = $self->{attrs};
2523 my $from = $attrs->{from}
2524 || [ { $attrs->{alias} => $source->from } ];
2526 my $seen = { %{$attrs->{seen_join}||{}} };
2528 # we need to take the prefetch the attrs into account before we
2529 # ->_resolve_join as otherwise they get lost - captainL
2530 my $merged = $self->_merge_attr( $attrs->{join}, $attrs->{prefetch} );
2532 push @$from, $source->_resolve_join($merged, $attrs->{alias}, $seen) if ($merged);
2534 ++$seen->{-relation_chain_depth};
2536 push @$from, $source->_resolve_join($extra_join, $attrs->{alias}, $seen);
2538 ++$seen->{-relation_chain_depth};
2540 return ($from,$seen);
2543 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
2544 sub _resolved_attrs_copy {
2546 return { %{$self->_resolved_attrs (@_)} };
2549 sub _resolved_attrs {
2551 return $self->{_attrs} if $self->{_attrs};
2553 my $attrs = { %{ $self->{attrs} || {} } };
2554 my $source = $self->result_source;
2555 my $alias = $attrs->{alias};
2557 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
2560 # build columns (as long as select isn't set) into a set of as/select hashes
2561 unless ( $attrs->{select} ) {
2563 ( ref($_) eq 'HASH' )
2567 /^\Q${alias}.\E(.+)$/
2578 } ( ref($attrs->{columns}) eq 'ARRAY' ) ? @{ delete $attrs->{columns}} : (delete $attrs->{columns} || $source->columns );
2580 # add the additional columns on
2581 foreach ( 'include_columns', '+columns' ) {
2582 push @colbits, map {
2583 ( ref($_) eq 'HASH' )
2585 : { ( split( /\./, $_ ) )[-1] => ( /\./ ? $_ : "${alias}.$_" ) }
2586 } ( ref($attrs->{$_}) eq 'ARRAY' ) ? @{ delete $attrs->{$_} } : delete $attrs->{$_} if ( $attrs->{$_} );
2589 # start with initial select items
2590 if ( $attrs->{select} ) {
2592 ( ref $attrs->{select} eq 'ARRAY' )
2593 ? [ @{ $attrs->{select} } ]
2594 : [ $attrs->{select} ];
2598 ref $attrs->{as} eq 'ARRAY'
2599 ? [ @{ $attrs->{as} } ]
2602 : [ map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{ $attrs->{select} } ]
2607 # otherwise we intialise select & as to empty
2608 $attrs->{select} = [];
2612 # now add colbits to select/as
2613 push( @{ $attrs->{select} }, map { values( %{$_} ) } @colbits );
2614 push( @{ $attrs->{as} }, map { keys( %{$_} ) } @colbits );
2617 if ( $adds = delete $attrs->{'+select'} ) {
2618 $adds = [$adds] unless ref $adds eq 'ARRAY';
2620 @{ $attrs->{select} },
2621 map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds
2624 if ( $adds = delete $attrs->{'+as'} ) {
2625 $adds = [$adds] unless ref $adds eq 'ARRAY';
2626 push( @{ $attrs->{as} }, @$adds );
2629 $attrs->{from} ||= [ { $self->{attrs}{alias} => $source->from } ];
2631 if ( exists $attrs->{join} || exists $attrs->{prefetch} ) {
2632 my $join = delete $attrs->{join} || {};
2634 if ( defined $attrs->{prefetch} ) {
2635 $join = $self->_merge_attr( $join, $attrs->{prefetch} );
2639 $attrs->{from} = # have to copy here to avoid corrupting the original
2641 @{ $attrs->{from} },
2642 $source->_resolve_join(
2643 $join, $alias, { %{ $attrs->{seen_join} || {} } }
2649 if ( $attrs->{order_by} ) {
2650 $attrs->{order_by} = (
2651 ref( $attrs->{order_by} ) eq 'ARRAY'
2652 ? [ @{ $attrs->{order_by} } ]
2653 : [ $attrs->{order_by} ]
2657 $attrs->{order_by} = [];
2660 my $collapse = $attrs->{collapse} || {};
2661 if ( my $prefetch = delete $attrs->{prefetch} ) {
2662 $prefetch = $self->_merge_attr( {}, $prefetch );
2664 foreach my $p ( ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch) ) {
2666 # bring joins back to level of current class
2667 my $join_map = $self->_joinpath_aliases ($attrs->{from}, $attrs->{seen_join});
2669 $source->_resolve_prefetch( $p, $alias, $join_map, \@pre_order, $collapse );
2670 push( @{ $attrs->{select} }, map { $_->[0] } @prefetch );
2671 push( @{ $attrs->{as} }, map { $_->[1] } @prefetch );
2673 push( @{ $attrs->{order_by} }, @pre_order );
2676 if (delete $attrs->{distinct}) {
2677 $attrs->{group_by} ||= [ grep { !ref($_) || (ref($_) ne 'HASH') } @{$attrs->{select}} ];
2680 $attrs->{collapse} = $collapse;
2682 if ( $attrs->{page} and not defined $attrs->{offset} ) {
2683 $attrs->{offset} = ( $attrs->{rows} * ( $attrs->{page} - 1 ) );
2686 return $self->{_attrs} = $attrs;
2689 sub _joinpath_aliases {
2690 my ($self, $fromspec, $seen) = @_;
2693 return $paths unless ref $fromspec eq 'ARRAY';
2695 for my $j (@$fromspec) {
2697 next if ref $j ne 'ARRAY';
2698 next if $j->[0]{-relation_chain_depth} < ( $seen->{-relation_chain_depth} || 0);
2701 $p = $p->{$_} ||= {} for @{$j->[0]{-join_path}};
2702 push @{$p->{-join_aliases} }, $j->[0]{-join_alias};
2709 my ($self, $attr) = @_;
2711 if (ref $attr eq 'HASH') {
2712 return $self->_rollout_hash($attr);
2713 } elsif (ref $attr eq 'ARRAY') {
2714 return $self->_rollout_array($attr);
2720 sub _rollout_array {
2721 my ($self, $attr) = @_;
2724 foreach my $element (@{$attr}) {
2725 if (ref $element eq 'HASH') {
2726 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
2727 } elsif (ref $element eq 'ARRAY') {
2728 # XXX - should probably recurse here
2729 push( @rolled_array, @{$self->_rollout_array($element)} );
2731 push( @rolled_array, $element );
2734 return \@rolled_array;
2738 my ($self, $attr) = @_;
2741 foreach my $key (keys %{$attr}) {
2742 push( @rolled_array, { $key => $attr->{$key} } );
2744 return \@rolled_array;
2747 sub _calculate_score {
2748 my ($self, $a, $b) = @_;
2750 if (ref $b eq 'HASH') {
2751 my ($b_key) = keys %{$b};
2752 if (ref $a eq 'HASH') {
2753 my ($a_key) = keys %{$a};
2754 if ($a_key eq $b_key) {
2755 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
2760 return ($a eq $b_key) ? 1 : 0;
2763 if (ref $a eq 'HASH') {
2764 my ($a_key) = keys %{$a};
2765 return ($b eq $a_key) ? 1 : 0;
2767 return ($b eq $a) ? 1 : 0;
2773 my ($self, $orig, $import) = @_;
2775 return $import unless defined($orig);
2776 return $orig unless defined($import);
2778 $orig = $self->_rollout_attr($orig);
2779 $import = $self->_rollout_attr($import);
2782 foreach my $import_element ( @{$import} ) {
2783 # find best candidate from $orig to merge $b_element into
2784 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
2785 foreach my $orig_element ( @{$orig} ) {
2786 my $score = $self->_calculate_score( $orig_element, $import_element );
2787 if ($score > $best_candidate->{score}) {
2788 $best_candidate->{position} = $position;
2789 $best_candidate->{score} = $score;
2793 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
2795 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
2796 push( @{$orig}, $import_element );
2798 my $orig_best = $orig->[$best_candidate->{position}];
2799 # merge orig_best and b_element together and replace original with merged
2800 if (ref $orig_best ne 'HASH') {
2801 $orig->[$best_candidate->{position}] = $import_element;
2802 } elsif (ref $import_element eq 'HASH') {
2803 my ($key) = keys %{$orig_best};
2804 $orig->[$best_candidate->{position}] = { $key => $self->_merge_attr($orig_best->{$key}, $import_element->{$key}) };
2807 $seen_keys->{$import_key} = 1; # don't merge the same key twice
2817 $self->_source_handle($_[0]->handle);
2819 $self->_source_handle->resolve;
2823 =head2 throw_exception
2825 See L<DBIx::Class::Schema/throw_exception> for details.
2829 sub throw_exception {
2831 if (ref $self && $self->_source_handle->schema) {
2832 $self->_source_handle->schema->throw_exception(@_)
2839 # XXX: FIXME: Attributes docs need clearing up
2843 Attributes are used to refine a ResultSet in various ways when
2844 searching for data. They can be passed to any method which takes an
2845 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
2848 These are in no particular order:
2854 =item Value: ( $order_by | \@order_by | \%order_by )
2858 Which column(s) to order the results by. If a single column name, or
2859 an arrayref of names is supplied, the argument is passed through
2860 directly to SQL. The hashref syntax allows for connection-agnostic
2861 specification of ordering direction:
2863 For descending order:
2865 order_by => { -desc => [qw/col1 col2 col3/] }
2867 For explicit ascending order:
2869 order_by => { -asc => 'col' }
2871 The old scalarref syntax (i.e. order_by => \'year DESC') is still
2872 supported, although you are strongly encouraged to use the hashref
2873 syntax as outlined above.
2879 =item Value: \@columns
2883 Shortcut to request a particular set of columns to be retrieved. Each
2884 column spec may be a string (a table column name), or a hash (in which
2885 case the key is the C<as> value, and the value is used as the C<select>
2886 expression). Adds C<me.> onto the start of any column without a C<.> in
2887 it and sets C<select> from that, then auto-populates C<as> from
2888 C<select> as normal. (You may also use the C<cols> attribute, as in
2889 earlier versions of DBIC.)
2895 =item Value: \@columns
2899 Indicates additional columns to be selected from storage. Works the same
2900 as L</columns> but adds columns to the selection. (You may also use the
2901 C<include_columns> attribute, as in earlier versions of DBIC). For
2904 $schema->resultset('CD')->search(undef, {
2905 '+columns' => ['artist.name'],
2909 would return all CDs and include a 'name' column to the information
2910 passed to object inflation. Note that the 'artist' is the name of the
2911 column (or relationship) accessor, and 'name' is the name of the column
2912 accessor in the related table.
2914 =head2 include_columns
2918 =item Value: \@columns
2922 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
2928 =item Value: \@select_columns
2932 Indicates which columns should be selected from the storage. You can use
2933 column names, or in the case of RDBMS back ends, function or stored procedure
2936 $rs = $schema->resultset('Employee')->search(undef, {
2939 { count => 'employeeid' },
2944 When you use function/stored procedure names and do not supply an C<as>
2945 attribute, the column names returned are storage-dependent. E.g. MySQL would
2946 return a column named C<count(employeeid)> in the above example.
2952 Indicates additional columns to be selected from storage. Works the same as
2953 L</select> but adds columns to the selection.
2961 Indicates additional column names for those added via L</+select>. See L</as>.
2969 =item Value: \@inflation_names
2973 Indicates column names for object inflation. That is, C<as>
2974 indicates the name that the column can be accessed as via the
2975 C<get_column> method (or via the object accessor, B<if one already
2976 exists>). It has nothing to do with the SQL code C<SELECT foo AS bar>.
2978 The C<as> attribute is used in conjunction with C<select>,
2979 usually when C<select> contains one or more function or stored
2982 $rs = $schema->resultset('Employee')->search(undef, {
2985 { count => 'employeeid' }
2987 as => ['name', 'employee_count'],
2990 my $employee = $rs->first(); # get the first Employee
2992 If the object against which the search is performed already has an accessor
2993 matching a column name specified in C<as>, the value can be retrieved using
2994 the accessor as normal:
2996 my $name = $employee->name();
2998 If on the other hand an accessor does not exist in the object, you need to
2999 use C<get_column> instead:
3001 my $employee_count = $employee->get_column('employee_count');
3003 You can create your own accessors if required - see
3004 L<DBIx::Class::Manual::Cookbook> for details.
3006 Please note: This will NOT insert an C<AS employee_count> into the SQL
3007 statement produced, it is used for internal access only. Thus
3008 attempting to use the accessor in an C<order_by> clause or similar
3009 will fail miserably.
3011 To get around this limitation, you can supply literal SQL to your
3012 C<select> attibute that contains the C<AS alias> text, eg:
3014 select => [\'myfield AS alias']
3020 =item Value: ($rel_name | \@rel_names | \%rel_names)
3024 Contains a list of relationships that should be joined for this query. For
3027 # Get CDs by Nine Inch Nails
3028 my $rs = $schema->resultset('CD')->search(
3029 { 'artist.name' => 'Nine Inch Nails' },
3030 { join => 'artist' }
3033 Can also contain a hash reference to refer to the other relation's relations.
3036 package MyApp::Schema::Track;
3037 use base qw/DBIx::Class/;
3038 __PACKAGE__->table('track');
3039 __PACKAGE__->add_columns(qw/trackid cd position title/);
3040 __PACKAGE__->set_primary_key('trackid');
3041 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3044 # In your application
3045 my $rs = $schema->resultset('Artist')->search(
3046 { 'track.title' => 'Teardrop' },
3048 join => { cd => 'track' },
3049 order_by => 'artist.name',
3053 You need to use the relationship (not the table) name in conditions,
3054 because they are aliased as such. The current table is aliased as "me", so
3055 you need to use me.column_name in order to avoid ambiguity. For example:
3057 # Get CDs from 1984 with a 'Foo' track
3058 my $rs = $schema->resultset('CD')->search(
3061 'tracks.name' => 'Foo'
3063 { join => 'tracks' }
3066 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3067 similarly for a third time). For e.g.
3069 my $rs = $schema->resultset('Artist')->search({
3070 'cds.title' => 'Down to Earth',
3071 'cds_2.title' => 'Popular',
3073 join => [ qw/cds cds/ ],
3076 will return a set of all artists that have both a cd with title 'Down
3077 to Earth' and a cd with title 'Popular'.
3079 If you want to fetch related objects from other tables as well, see C<prefetch>
3082 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3088 =item Value: ($rel_name | \@rel_names | \%rel_names)
3092 Contains one or more relationships that should be fetched along with
3093 the main query (when they are accessed afterwards the data will
3094 already be available, without extra queries to the database). This is
3095 useful for when you know you will need the related objects, because it
3096 saves at least one query:
3098 my $rs = $schema->resultset('Tag')->search(
3107 The initial search results in SQL like the following:
3109 SELECT tag.*, cd.*, artist.* FROM tag
3110 JOIN cd ON tag.cd = cd.cdid
3111 JOIN artist ON cd.artist = artist.artistid
3113 L<DBIx::Class> has no need to go back to the database when we access the
3114 C<cd> or C<artist> relationships, which saves us two SQL statements in this
3117 Simple prefetches will be joined automatically, so there is no need
3118 for a C<join> attribute in the above search.
3120 C<prefetch> can be used with the following relationship types: C<belongs_to>,
3121 C<has_one> (or if you're using C<add_relationship>, any relationship declared
3122 with an accessor type of 'single' or 'filter'). A more complex example that
3123 prefetches an artists cds, the tracks on those cds, and the tags associted
3124 with that artist is given below (assuming many-to-many from artists to tags):
3126 my $rs = $schema->resultset('Artist')->search(
3130 { cds => 'tracks' },
3131 { artist_tags => 'tags' }
3137 B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
3138 attributes will be ignored.
3148 Makes the resultset paged and specifies the page to retrieve. Effectively
3149 identical to creating a non-pages resultset and then calling ->page($page)
3152 If L<rows> attribute is not specified it defualts to 10 rows per page.
3154 When you have a paged resultset, L</count> will only return the number
3155 of rows in the page. To get the total, use the L</pager> and call
3156 C<total_entries> on it.
3166 Specifes the maximum number of rows for direct retrieval or the number of
3167 rows per page if the page attribute or method is used.
3173 =item Value: $offset
3177 Specifies the (zero-based) row number for the first row to be returned, or the
3178 of the first row of the first page if paging is used.
3184 =item Value: \@columns
3188 A arrayref of columns to group by. Can include columns of joined tables.
3190 group_by => [qw/ column1 column2 ... /]
3196 =item Value: $condition
3200 HAVING is a select statement attribute that is applied between GROUP BY and
3201 ORDER BY. It is applied to the after the grouping calculations have been
3204 having => { 'count(employee)' => { '>=', 100 } }
3210 =item Value: (0 | 1)
3214 Set to 1 to group by all columns.
3220 Adds to the WHERE clause.
3222 # only return rows WHERE deleted IS NULL for all searches
3223 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
3225 Can be overridden by passing C<{ where => undef }> as an attribute
3232 Set to 1 to cache search results. This prevents extra SQL queries if you
3233 revisit rows in your ResultSet:
3235 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
3237 while( my $artist = $resultset->next ) {
3241 $rs->first; # without cache, this would issue a query
3243 By default, searches are not cached.
3245 For more examples of using these attributes, see
3246 L<DBIx::Class::Manual::Cookbook>.
3252 =item Value: \@from_clause
3256 The C<from> attribute gives you manual control over the C<FROM> clause of SQL
3257 statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
3260 NOTE: Use this on your own risk. This allows you to shoot off your foot!
3262 C<join> will usually do what you need and it is strongly recommended that you
3263 avoid using C<from> unless you cannot achieve the desired result using C<join>.
3264 And we really do mean "cannot", not just tried and failed. Attempting to use
3265 this because you're having problems with C<join> is like trying to use x86
3266 ASM because you've got a syntax error in your C. Trust us on this.
3268 Now, if you're still really, really sure you need to use this (and if you're
3269 not 100% sure, ask the mailing list first), here's an explanation of how this
3272 The syntax is as follows -
3275 { <alias1> => <table1> },
3277 { <alias2> => <table2>, -join_type => 'inner|left|right' },
3278 [], # nested JOIN (optional)
3279 { <table1.column1> => <table2.column2>, ... (more conditions) },
3281 # More of the above [ ] may follow for additional joins
3288 ON <table1.column1> = <table2.column2>
3289 <more joins may follow>
3291 An easy way to follow the examples below is to remember the following:
3293 Anything inside "[]" is a JOIN
3294 Anything inside "{}" is a condition for the enclosing JOIN
3296 The following examples utilize a "person" table in a family tree application.
3297 In order to express parent->child relationships, this table is self-joined:
3299 # Person->belongs_to('father' => 'Person');
3300 # Person->belongs_to('mother' => 'Person');
3302 C<from> can be used to nest joins. Here we return all children with a father,
3303 then search against all mothers of those children:
3305 $rs = $schema->resultset('Person')->search(
3308 alias => 'mother', # alias columns in accordance with "from"
3310 { mother => 'person' },
3313 { child => 'person' },
3315 { father => 'person' },
3316 { 'father.person_id' => 'child.father_id' }
3319 { 'mother.person_id' => 'child.mother_id' }
3326 # SELECT mother.* FROM person mother
3329 # JOIN person father
3330 # ON ( father.person_id = child.father_id )
3332 # ON ( mother.person_id = child.mother_id )
3334 The type of any join can be controlled manually. To search against only people
3335 with a father in the person table, we could explicitly use C<INNER JOIN>:
3337 $rs = $schema->resultset('Person')->search(
3340 alias => 'child', # alias columns in accordance with "from"
3342 { child => 'person' },
3344 { father => 'person', -join_type => 'inner' },
3345 { 'father.id' => 'child.father_id' }
3352 # SELECT child.* FROM person child
3353 # INNER JOIN person father ON child.father_id = father.id
3355 If you need to express really complex joins or you need a subselect, you
3356 can supply literal SQL to C<from> via a scalar reference. In this case
3357 the contents of the scalar will replace the table name asscoiated with the
3360 WARNING: This technique might very well not work as expected on chained
3361 searches - you have been warned.
3363 # Assuming the Event resultsource is defined as:
3365 MySchema::Event->add_columns (
3368 is_auto_increment => 1,
3377 MySchema::Event->set_primary_key ('sequence');
3379 # This will get back the latest event for every location. The column
3380 # selector is still provided by DBIC, all we do is add a JOIN/WHERE
3381 # combo to limit the resultset
3383 $rs = $schema->resultset('Event');
3384 $table = $rs->result_source->name;
3385 $latest = $rs->search (
3388 (SELECT e1.* FROM $table e1
3390 ON e1.location = e2.location
3391 AND e1.sequence < e2.sequence
3392 WHERE e2.sequence is NULL
3397 # Equivalent SQL (with the DBIC chunks added):
3399 SELECT me.sequence, me.location, me.type FROM
3400 (SELECT e1.* FROM events e1
3402 ON e1.location = e2.location
3403 AND e1.sequence < e2.sequence
3404 WHERE e2.sequence is NULL
3411 =item Value: ( 'update' | 'shared' )
3415 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT