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;
665 return $self->{cursor}
666 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
667 $attrs->{where},$attrs);
674 =item Arguments: $cond?
676 =item Return Value: $row_object?
680 my $cd = $schema->resultset('CD')->single({ year => 2001 });
682 Inflates the first result without creating a cursor if the resultset has
683 any records in it; if not returns nothing. Used by L</find> as a lean version of
686 While this method can take an optional search condition (just like L</search>)
687 being a fast-code-path it does not recognize search attributes. If you need to
688 add extra joins or similar, call L</search> and then chain-call L</single> on the
689 L<DBIx::Class::ResultSet> returned.
695 As of 0.08100, this method enforces the assumption that the preceeding
696 query returns only one row. If more than one row is returned, you will receive
699 Query returned more than one row
701 In this case, you should be using L</next> or L</find> instead, or if you really
702 know what you are doing, use the L</rows> attribute to explicitly limit the size
705 This method will also throw an exception if it is called on a resultset prefetching
706 has_many, as such a prefetch implies fetching multiple rows from the database in
707 order to assemble the resulting object.
714 my ($self, $where) = @_;
716 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
719 my $attrs = $self->_resolved_attrs_copy;
721 if (keys %{$attrs->{collapse}}) {
722 $self->throw_exception(
723 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
728 if (defined $attrs->{where}) {
731 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
732 $where, delete $attrs->{where} ]
735 $attrs->{where} = $where;
739 # XXX: Disabled since it doesn't infer uniqueness in all cases
740 # unless ($self->_is_unique_query($attrs->{where})) {
741 # carp "Query not guaranteed to return a single row"
742 # . "; please declare your unique constraints or use search instead";
745 my @data = $self->result_source->storage->select_single(
746 $attrs->{from}, $attrs->{select},
747 $attrs->{where}, $attrs
750 return (@data ? ($self->_construct_object(@data))[0] : undef);
756 # Try to determine if the specified query is guaranteed to be unique, based on
757 # the declared unique constraints.
759 sub _is_unique_query {
760 my ($self, $query) = @_;
762 my $collapsed = $self->_collapse_query($query);
763 my $alias = $self->{attrs}{alias};
765 foreach my $name ($self->result_source->unique_constraint_names) {
766 my @unique_cols = map {
768 } $self->result_source->unique_constraint_columns($name);
770 # Count the values for each unique column
771 my %seen = map { $_ => 0 } @unique_cols;
773 foreach my $key (keys %$collapsed) {
774 my $aliased = $key =~ /\./ ? $key : "$alias.$key";
775 next unless exists $seen{$aliased}; # Additional constraints are okay
776 $seen{$aliased} = scalar keys %{ $collapsed->{$key} };
779 # If we get 0 or more than 1 value for a column, it's not necessarily unique
780 return 1 unless grep { $_ != 1 } values %seen;
788 # Recursively collapse the query, accumulating values for each column.
790 sub _collapse_query {
791 my ($self, $query, $collapsed) = @_;
795 if (ref $query eq 'ARRAY') {
796 foreach my $subquery (@$query) {
797 next unless ref $subquery; # -or
798 $collapsed = $self->_collapse_query($subquery, $collapsed);
801 elsif (ref $query eq 'HASH') {
802 if (keys %$query and (keys %$query)[0] eq '-and') {
803 foreach my $subquery (@{$query->{-and}}) {
804 $collapsed = $self->_collapse_query($subquery, $collapsed);
808 foreach my $col (keys %$query) {
809 my $value = $query->{$col};
810 $collapsed->{$col}{$value}++;
822 =item Arguments: $cond?
824 =item Return Value: $resultsetcolumn
828 my $max_length = $rs->get_column('length')->max;
830 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
835 my ($self, $column) = @_;
836 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
844 =item Arguments: $cond, \%attrs?
846 =item Return Value: $resultset (scalar context), @row_objs (list context)
850 # WHERE title LIKE '%blue%'
851 $cd_rs = $rs->search_like({ title => '%blue%'});
853 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
854 that this is simply a convenience method retained for ex Class::DBI users.
855 You most likely want to use L</search> with specific operators.
857 For more information, see L<DBIx::Class::Manual::Cookbook>.
859 This method is deprecated and will be removed in 0.09. Use L</search()>
860 instead. An example conversion is:
862 ->search_like({ foo => 'bar' });
866 ->search({ foo => { like => 'bar' } });
873 'search_like() is deprecated and will be removed in DBIC version 0.09.'
874 .' Instead use ->search({ x => { -like => "y%" } })'
875 .' (note the outer pair of {}s - they are important!)'
877 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
878 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
879 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
880 return $class->search($query, { %$attrs });
887 =item Arguments: $first, $last
889 =item Return Value: $resultset (scalar context), @row_objs (list context)
893 Returns a resultset or object list representing a subset of elements from the
894 resultset slice is called on. Indexes are from 0, i.e., to get the first
897 my ($one, $two, $three) = $rs->slice(0, 2);
902 my ($self, $min, $max) = @_;
903 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
904 $attrs->{offset} = $self->{attrs}{offset} || 0;
905 $attrs->{offset} += $min;
906 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
907 return $self->search(undef(), $attrs);
908 #my $slice = (ref $self)->new($self->result_source, $attrs);
909 #return (wantarray ? $slice->all : $slice);
916 =item Arguments: none
918 =item Return Value: $result?
922 Returns the next element in the resultset (C<undef> is there is none).
924 Can be used to efficiently iterate over records in the resultset:
926 my $rs = $schema->resultset('CD')->search;
927 while (my $cd = $rs->next) {
931 Note that you need to store the resultset object, and call C<next> on it.
932 Calling C<< resultset('Table')->next >> repeatedly will always return the
933 first record from the resultset.
939 if (my $cache = $self->get_cache) {
940 $self->{all_cache_position} ||= 0;
941 return $cache->[$self->{all_cache_position}++];
943 if ($self->{attrs}{cache}) {
944 $self->{all_cache_position} = 1;
945 return ($self->all)[0];
947 if ($self->{stashed_objects}) {
948 my $obj = shift(@{$self->{stashed_objects}});
949 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
953 exists $self->{stashed_row}
954 ? @{delete $self->{stashed_row}}
955 : $self->cursor->next
957 return undef unless (@row);
958 my ($row, @more) = $self->_construct_object(@row);
959 $self->{stashed_objects} = \@more if @more;
963 sub _construct_object {
964 my ($self, @row) = @_;
965 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row);
966 my @new = $self->result_class->inflate_result($self->result_source, @$info);
967 @new = $self->{_attrs}{record_filter}->(@new)
968 if exists $self->{_attrs}{record_filter};
972 sub _collapse_result {
973 my ($self, $as_proto, $row) = @_;
977 # 'foo' => [ undef, 'foo' ]
978 # 'foo.bar' => [ 'foo', 'bar' ]
979 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
981 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
983 my %collapse = %{$self->{_attrs}{collapse}||{}};
987 # if we're doing collapsing (has_many prefetch) we need to grab records
988 # until the PK changes, so fill @pri_index. if not, we leave it empty so
989 # we know we don't have to bother.
991 # the reason for not using the collapse stuff directly is because if you
992 # had for e.g. two artists in a row with no cds, the collapse info for
993 # both would be NULL (undef) so you'd lose the second artist
995 # store just the index so we can check the array positions from the row
996 # without having to contruct the full hash
998 if (keys %collapse) {
999 my %pri = map { ($_ => 1) } $self->result_source->primary_columns;
1000 foreach my $i (0 .. $#construct_as) {
1001 next if defined($construct_as[$i][0]); # only self table
1002 if (delete $pri{$construct_as[$i][1]}) {
1003 push(@pri_index, $i);
1005 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
1009 # no need to do an if, it'll be empty if @pri_index is empty anyway
1011 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
1015 do { # no need to check anything at the front, we always want the first row
1019 foreach my $this_as (@construct_as) {
1020 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
1023 push(@const_rows, \%const);
1025 } until ( # no pri_index => no collapse => drop straight out
1028 do { # get another row, stash it, drop out if different PK
1030 @copy = $self->cursor->next;
1031 $self->{stashed_row} = \@copy;
1033 # last thing in do block, counts as true if anything doesn't match
1035 # check xor defined first for NULL vs. NOT NULL then if one is
1036 # defined the other must be so check string equality
1039 (defined $pri_vals{$_} ^ defined $copy[$_])
1040 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
1045 my $alias = $self->{attrs}{alias};
1052 foreach my $const (@const_rows) {
1053 scalar @const_keys or do {
1054 @const_keys = sort { length($a) <=> length($b) } keys %$const;
1056 foreach my $key (@const_keys) {
1059 my @parts = split(/\./, $key);
1061 my $data = $const->{$key};
1062 foreach my $p (@parts) {
1063 $target = $target->[1]->{$p} ||= [];
1065 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
1066 # collapsing at this point and on final part
1067 my $pos = $collapse_pos{$cur};
1068 CK: foreach my $ck (@ckey) {
1069 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
1070 $collapse_pos{$cur} = $data;
1071 delete @collapse_pos{ # clear all positioning for sub-entries
1072 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
1079 if (exists $collapse{$cur}) {
1080 $target = $target->[-1];
1083 $target->[0] = $data;
1085 $info->[0] = $const->{$key};
1093 =head2 result_source
1097 =item Arguments: $result_source?
1099 =item Return Value: $result_source
1103 An accessor for the primary ResultSource object from which this ResultSet
1110 =item Arguments: $result_class?
1112 =item Return Value: $result_class
1116 An accessor for the class to use when creating row objects. Defaults to
1117 C<< result_source->result_class >> - which in most cases is the name of the
1118 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1120 Note that changing the result_class will also remove any components
1121 that were originally loaded in the source class via
1122 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1123 in the original source class will not run.
1128 my ($self, $result_class) = @_;
1129 if ($result_class) {
1130 $self->ensure_class_loaded($result_class);
1131 $self->_result_class($result_class);
1133 $self->_result_class;
1140 =item Arguments: $cond, \%attrs??
1142 =item Return Value: $count
1146 Performs an SQL C<COUNT> with the same query as the resultset was built
1147 with to find the number of elements. Passing arguments is equivalent to
1148 C<< $rs->search ($cond, \%attrs)->count >>
1154 return $self->search(@_)->count if @_ and defined $_[0];
1155 return scalar @{ $self->get_cache } if $self->get_cache;
1157 my $attrs = $self->_resolved_attrs_copy;
1159 # this is a little optimization - it is faster to do the limit
1160 # adjustments in software, instead of a subquery
1161 my $rows = delete $attrs->{rows};
1162 my $offset = delete $attrs->{offset};
1165 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1166 $crs = $self->_count_subq_rs ($attrs);
1169 $crs = $self->_count_rs ($attrs);
1171 my $count = $crs->next;
1173 $count -= $offset if $offset;
1174 $count = $rows if $rows and $rows < $count;
1175 $count = 0 if ($count < 0);
1184 =item Arguments: $cond, \%attrs??
1186 =item Return Value: $count_rs
1190 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1191 This can be very handy for subqueries:
1193 ->search( { amount => $some_rs->count_rs->as_query } )
1195 As with regular resultsets the SQL query will be executed only after
1196 the resultset is accessed via L</next> or L</all>. That would return
1197 the same single value obtainable via L</count>.
1203 return $self->search(@_)->count_rs if @_;
1205 # this may look like a lack of abstraction (count() does about the same)
1206 # but in fact an _rs *must* use a subquery for the limits, as the
1207 # software based limiting can not be ported if this $rs is to be used
1208 # in a subquery itself (i.e. ->as_query)
1209 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1210 return $self->_count_subq_rs;
1213 return $self->_count_rs;
1218 # returns a ResultSetColumn object tied to the count query
1221 my ($self, $attrs) = @_;
1223 my $rsrc = $self->result_source;
1224 $attrs ||= $self->_resolved_attrs;
1226 my $tmp_attrs = { %$attrs };
1228 # take off any limits, record_filter is cdbi, and no point of ordering a count
1229 delete $tmp_attrs->{$_} for (qw/select as rows offset order_by record_filter/);
1231 # overwrite the selector (supplied by the storage)
1232 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $tmp_attrs);
1233 $tmp_attrs->{as} = 'count';
1235 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1241 # same as above but uses a subquery
1243 sub _count_subq_rs {
1244 my ($self, $attrs) = @_;
1246 my $rsrc = $self->result_source;
1247 $attrs ||= $self->_resolved_attrs_copy;
1249 my $sub_attrs = { %$attrs };
1251 # these can not go in the subquery, and there is no point of ordering it
1252 delete $sub_attrs->{$_} for qw/collapse select as order_by/;
1254 # if we prefetch, we group_by primary keys only as this is what we would get out of the rs via ->next/->all
1255 # clobber old group_by regardless
1256 if ( keys %{$attrs->{collapse}} ) {
1257 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } ($rsrc->primary_columns) ]
1260 $sub_attrs->{select} = $rsrc->storage->_subq_count_select ($rsrc, $sub_attrs);
1263 count_subq => $rsrc->resultset_class->new ($rsrc, $sub_attrs )->as_query
1266 # the subquery replaces this
1267 delete $attrs->{$_} for qw/where bind collapse group_by having having_bind rows offset/;
1269 return $self->_count_rs ($attrs);
1277 =head2 count_literal
1281 =item Arguments: $sql_fragment, @bind_values
1283 =item Return Value: $count
1287 Counts the results in a literal query. Equivalent to calling L</search_literal>
1288 with the passed arguments, then L</count>.
1292 sub count_literal { shift->search_literal(@_)->count; }
1298 =item Arguments: none
1300 =item Return Value: @objects
1304 Returns all elements in the resultset. Called implicitly if the resultset
1305 is returned in list context.
1312 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1315 return @{ $self->get_cache } if $self->get_cache;
1319 # TODO: don't call resolve here
1320 if (keys %{$self->_resolved_attrs->{collapse}}) {
1321 # if ($self->{attrs}{prefetch}) {
1322 # Using $self->cursor->all is really just an optimisation.
1323 # If we're collapsing has_many prefetches it probably makes
1324 # very little difference, and this is cleaner than hacking
1325 # _construct_object to survive the approach
1326 my @row = $self->cursor->next;
1328 push(@obj, $self->_construct_object(@row));
1329 @row = (exists $self->{stashed_row}
1330 ? @{delete $self->{stashed_row}}
1331 : $self->cursor->next);
1334 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1337 $self->set_cache(\@obj) if $self->{attrs}{cache};
1345 =item Arguments: none
1347 =item Return Value: $self
1351 Resets the resultset's cursor, so you can iterate through the elements again.
1357 delete $self->{_attrs} if exists $self->{_attrs};
1358 $self->{all_cache_position} = 0;
1359 $self->cursor->reset;
1367 =item Arguments: none
1369 =item Return Value: $object?
1373 Resets the resultset and returns an object for the first result (if the
1374 resultset returns anything).
1379 return $_[0]->reset->next;
1385 # Determines whether and what type of subquery is required for the $rs operation.
1386 # If grouping is necessary either supplies its own, or verifies the current one
1387 # After all is done delegates to the proper storage method.
1389 sub _rs_update_delete {
1390 my ($self, $op, $values) = @_;
1392 my $rsrc = $self->result_source;
1394 my $needs_group_by_subq = $self->_has_resolved_attr (qw/collapse group_by -join/);
1395 my $needs_subq = $self->_has_resolved_attr (qw/row offset/);
1397 if ($needs_group_by_subq or $needs_subq) {
1399 # make a new $rs selecting only the PKs (that's all we really need)
1400 my $attrs = $self->_resolved_attrs_copy;
1402 delete $attrs->{$_} for qw/collapse select as/;
1403 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->primary_columns) ];
1405 if ($needs_group_by_subq) {
1406 # make sure no group_by was supplied, or if there is one - make sure it matches
1407 # the columns compiled above perfectly. Anything else can not be sanely executed
1408 # on most databases so croak right then and there
1410 if (my $g = $attrs->{group_by}) {
1411 my @current_group_by = map
1412 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1413 (ref $g eq 'ARRAY' ? @$g : $g );
1416 join ("\x00", sort @current_group_by)
1418 join ("\x00", sort @{$attrs->{columns}} )
1420 $self->throw_exception (
1421 "You have just attempted a $op operation on a resultset which does group_by"
1422 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1423 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1424 . ' kind of queries. Please retry the operation with a modified group_by or'
1425 . ' without using one at all.'
1430 $attrs->{group_by} = $attrs->{columns};
1434 my $subrs = (ref $self)->new($rsrc, $attrs);
1436 return $self->result_source->storage->_subq_update_delete($subrs, $op, $values);
1439 return $rsrc->storage->$op(
1441 $op eq 'update' ? $values : (),
1442 $self->_cond_for_update_delete,
1448 # _cond_for_update_delete
1450 # update/delete require the condition to be modified to handle
1451 # the differing SQL syntax available. This transforms the $self->{cond}
1452 # appropriately, returning the new condition.
1454 sub _cond_for_update_delete {
1455 my ($self, $full_cond) = @_;
1458 $full_cond ||= $self->{cond};
1459 # No-op. No condition, we're updating/deleting everything
1460 return $cond unless ref $full_cond;
1462 if (ref $full_cond eq 'ARRAY') {
1466 foreach my $key (keys %{$_}) {
1468 $hash{$1} = $_->{$key};
1474 elsif (ref $full_cond eq 'HASH') {
1475 if ((keys %{$full_cond})[0] eq '-and') {
1477 my @cond = @{$full_cond->{-and}};
1478 for (my $i = 0; $i < @cond; $i++) {
1479 my $entry = $cond[$i];
1481 if (ref $entry eq 'HASH') {
1482 $hash = $self->_cond_for_update_delete($entry);
1485 $entry =~ /([^.]+)$/;
1486 $hash->{$1} = $cond[++$i];
1488 push @{$cond->{-and}}, $hash;
1492 foreach my $key (keys %{$full_cond}) {
1494 $cond->{$1} = $full_cond->{$key};
1499 $self->throw_exception("Can't update/delete on resultset with condition unless hash or array");
1510 =item Arguments: \%values
1512 =item Return Value: $storage_rv
1516 Sets the specified columns in the resultset to the supplied values in a
1517 single query. Return value will be true if the update succeeded or false
1518 if no records were updated; exact type of success value is storage-dependent.
1523 my ($self, $values) = @_;
1524 $self->throw_exception('Values for update must be a hash')
1525 unless ref $values eq 'HASH';
1527 return $self->_rs_update_delete ('update', $values);
1534 =item Arguments: \%values
1536 =item Return Value: 1
1540 Fetches all objects and updates them one at a time. Note that C<update_all>
1541 will run DBIC cascade triggers, while L</update> will not.
1546 my ($self, $values) = @_;
1547 $self->throw_exception('Values for update_all must be a hash')
1548 unless ref $values eq 'HASH';
1549 foreach my $obj ($self->all) {
1550 $obj->set_columns($values)->update;
1559 =item Arguments: none
1561 =item Return Value: $storage_rv
1565 Deletes the contents of the resultset from its result source. Note that this
1566 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
1567 to run. See also L<DBIx::Class::Row/delete>.
1569 Return value will be the amount of rows deleted; exact type of return value
1570 is storage-dependent.
1576 $self->throw_exception('delete does not accept any arguments')
1579 return $self->_rs_update_delete ('delete');
1586 =item Arguments: none
1588 =item Return Value: 1
1592 Fetches all objects and deletes them one at a time. Note that C<delete_all>
1593 will run DBIC cascade triggers, while L</delete> will not.
1599 $self->throw_exception('delete_all does not accept any arguments')
1602 $_->delete for $self->all;
1610 =item Arguments: \@data;
1614 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1615 For the arrayref of hashrefs style each hashref should be a structure suitable
1616 forsubmitting to a $resultset->create(...) method.
1618 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1619 to insert the data, as this is a faster method.
1621 Otherwise, each set of data is inserted into the database using
1622 L<DBIx::Class::ResultSet/create>, and a arrayref of the resulting row
1623 objects is returned.
1625 Example: Assuming an Artist Class that has many CDs Classes relating:
1627 my $Artist_rs = $schema->resultset("Artist");
1629 ## Void Context Example
1630 $Artist_rs->populate([
1631 { artistid => 4, name => 'Manufactured Crap', cds => [
1632 { title => 'My First CD', year => 2006 },
1633 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1636 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1637 { title => 'My parents sold me to a record company' ,year => 2005 },
1638 { title => 'Why Am I So Ugly?', year => 2006 },
1639 { title => 'I Got Surgery and am now Popular', year => 2007 }
1644 ## Array Context Example
1645 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1646 { name => "Artist One"},
1647 { name => "Artist Two"},
1648 { name => "Artist Three", cds=> [
1649 { title => "First CD", year => 2007},
1650 { title => "Second CD", year => 2008},
1654 print $ArtistOne->name; ## response is 'Artist One'
1655 print $ArtistThree->cds->count ## reponse is '2'
1657 For the arrayref of arrayrefs style, the first element should be a list of the
1658 fieldsnames to which the remaining elements are rows being inserted. For
1661 $Arstist_rs->populate([
1662 [qw/artistid name/],
1663 [100, 'A Formally Unknown Singer'],
1664 [101, 'A singer that jumped the shark two albums ago'],
1665 [102, 'An actually cool singer.'],
1668 Please note an important effect on your data when choosing between void and
1669 wantarray context. Since void context goes straight to C<insert_bulk> in
1670 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
1671 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
1672 create primary keys for you, you will find that your PKs are empty. In this
1673 case you will have to use the wantarray context in order to create those
1679 my $self = shift @_;
1680 my $data = ref $_[0][0] eq 'HASH'
1681 ? $_[0] : ref $_[0][0] eq 'ARRAY' ? $self->_normalize_populate_args($_[0]) :
1682 $self->throw_exception('Populate expects an arrayref of hashes or arrayref of arrayrefs');
1684 if(defined wantarray) {
1686 foreach my $item (@$data) {
1687 push(@created, $self->create($item));
1691 my ($first, @rest) = @$data;
1693 my @names = grep {!ref $first->{$_}} keys %$first;
1694 my @rels = grep { $self->result_source->has_relationship($_) } keys %$first;
1695 my @pks = $self->result_source->primary_columns;
1697 ## do the belongs_to relationships
1698 foreach my $index (0..$#$data) {
1700 # delegate to create() for any dataset without primary keys with specified relationships
1701 if (grep { !defined $data->[$index]->{$_} } @pks ) {
1703 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
1704 my @ret = $self->populate($data);
1710 foreach my $rel (@rels) {
1711 next unless ref $data->[$index]->{$rel} eq "HASH";
1712 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1713 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1714 my $related = $result->result_source->_resolve_condition(
1715 $result->result_source->relationship_info($reverse)->{cond},
1720 delete $data->[$index]->{$rel};
1721 $data->[$index] = {%{$data->[$index]}, %$related};
1723 push @names, keys %$related if $index == 0;
1727 ## do bulk insert on current row
1728 my @values = map { [ @$_{@names} ] } @$data;
1730 $self->result_source->storage->insert_bulk(
1731 $self->result_source,
1736 ## do the has_many relationships
1737 foreach my $item (@$data) {
1739 foreach my $rel (@rels) {
1740 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1742 my $parent = $self->find(map {{$_=>$item->{$_}} } @pks)
1743 || $self->throw_exception('Cannot find the relating object.');
1745 my $child = $parent->$rel;
1747 my $related = $child->result_source->_resolve_condition(
1748 $parent->result_source->relationship_info($rel)->{cond},
1753 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1754 my @populate = map { {%$_, %$related} } @rows_to_add;
1756 $child->populate( \@populate );
1762 =head2 _normalize_populate_args ($args)
1764 Private method used by L</populate> to normalize its incoming arguments. Factored
1765 out in case you want to subclass and accept new argument structures to the
1766 L</populate> method.
1770 sub _normalize_populate_args {
1771 my ($self, $data) = @_;
1772 my @names = @{shift(@$data)};
1773 my @results_to_create;
1774 foreach my $datum (@$data) {
1775 my %result_to_create;
1776 foreach my $index (0..$#names) {
1777 $result_to_create{$names[$index]} = $$datum[$index];
1779 push @results_to_create, \%result_to_create;
1781 return \@results_to_create;
1788 =item Arguments: none
1790 =item Return Value: $pager
1794 Return Value a L<Data::Page> object for the current resultset. Only makes
1795 sense for queries with a C<page> attribute.
1797 To get the full count of entries for a paged resultset, call
1798 C<total_entries> on the L<Data::Page> object.
1805 return $self->{pager} if $self->{pager};
1807 my $attrs = $self->{attrs};
1808 $self->throw_exception("Can't create pager for non-paged rs")
1809 unless $self->{attrs}{page};
1810 $attrs->{rows} ||= 10;
1812 # throw away the paging flags and re-run the count (possibly
1813 # with a subselect) to get the real total count
1814 my $count_attrs = { %$attrs };
1815 delete $count_attrs->{$_} for qw/rows offset page pager/;
1816 my $total_count = (ref $self)->new($self->result_source, $count_attrs)->count;
1818 return $self->{pager} = Data::Page->new(
1821 $self->{attrs}{page}
1829 =item Arguments: $page_number
1831 =item Return Value: $rs
1835 Returns a resultset for the $page_number page of the resultset on which page
1836 is called, where each page contains a number of rows equal to the 'rows'
1837 attribute set on the resultset (10 by default).
1842 my ($self, $page) = @_;
1843 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1850 =item Arguments: \%vals
1852 =item Return Value: $rowobject
1856 Creates a new row object in the resultset's result class and returns
1857 it. The row is not inserted into the database at this point, call
1858 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
1859 will tell you whether the row object has been inserted or not.
1861 Passes the hashref of input on to L<DBIx::Class::Row/new>.
1866 my ($self, $values) = @_;
1867 $self->throw_exception( "new_result needs a hash" )
1868 unless (ref $values eq 'HASH');
1871 my $alias = $self->{attrs}{alias};
1874 defined $self->{cond}
1875 && $self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION
1877 %new = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
1878 $new{-from_resultset} = [ keys %new ] if keys %new;
1880 $self->throw_exception(
1881 "Can't abstract implicit construct, condition not a hash"
1882 ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
1884 my $collapsed_cond = (
1886 ? $self->_collapse_cond($self->{cond})
1890 # precendence must be given to passed values over values inherited from
1891 # the cond, so the order here is important.
1892 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
1893 while( my($col,$value) = each %implied ){
1894 if(ref($value) eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '='){
1895 $new{$col} = $value->{'='};
1898 $new{$col} = $value if $self->_is_deterministic_value($value);
1904 %{ $self->_remove_alias($values, $alias) },
1905 -source_handle => $self->_source_handle,
1906 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
1909 return $self->result_class->new(\%new);
1912 # _is_deterministic_value
1914 # Make an effor to strip non-deterministic values from the condition,
1915 # to make sure new_result chokes less
1917 sub _is_deterministic_value {
1920 my $ref_type = ref $value;
1921 return 1 if $ref_type eq '' || $ref_type eq 'SCALAR';
1922 return 1 if Scalar::Util::blessed($value);
1926 # _has_resolved_attr
1928 # determines if the resultset defines at least one
1929 # of the attributes supplied
1931 # used to determine if a subquery is neccessary
1933 sub _has_resolved_attr {
1934 my ($self, @attr_names) = @_;
1936 my $attrs = $self->_resolved_attrs;
1940 for my $n (@attr_names) {
1941 ++$join_check_req if $n eq '-join';
1943 my $attr = $attrs->{$n};
1945 next if not defined $attr;
1947 if (ref $attr eq 'HASH') {
1948 return 1 if keys %$attr;
1950 elsif (ref $attr eq 'ARRAY') {
1958 # a resolved join is expressed as a multi-level from
1962 ref $attrs->{from} eq 'ARRAY'
1964 @{$attrs->{from}} > 1
1972 # Recursively collapse the condition.
1974 sub _collapse_cond {
1975 my ($self, $cond, $collapsed) = @_;
1979 if (ref $cond eq 'ARRAY') {
1980 foreach my $subcond (@$cond) {
1981 next unless ref $subcond; # -or
1982 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1985 elsif (ref $cond eq 'HASH') {
1986 if (keys %$cond and (keys %$cond)[0] eq '-and') {
1987 foreach my $subcond (@{$cond->{-and}}) {
1988 $collapsed = $self->_collapse_cond($subcond, $collapsed);
1992 foreach my $col (keys %$cond) {
1993 my $value = $cond->{$col};
1994 $collapsed->{$col} = $value;
2004 # Remove the specified alias from the specified query hash. A copy is made so
2005 # the original query is not modified.
2008 my ($self, $query, $alias) = @_;
2010 my %orig = %{ $query || {} };
2013 foreach my $key (keys %orig) {
2015 $unaliased{$key} = $orig{$key};
2018 $unaliased{$1} = $orig{$key}
2019 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2025 =head2 as_query (EXPERIMENTAL)
2029 =item Arguments: none
2031 =item Return Value: \[ $sql, @bind ]
2035 Returns the SQL query and bind vars associated with the invocant.
2037 This is generally used as the RHS for a subquery.
2039 B<NOTE>: This feature is still experimental.
2046 my $attrs = $self->_resolved_attrs_copy;
2051 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2052 # $sql also has no wrapping parenthesis in list ctx
2054 my $sqlbind = $self->result_source->storage
2055 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2064 =item Arguments: \%vals, \%attrs?
2066 =item Return Value: $rowobject
2070 my $artist = $schema->resultset('Artist')->find_or_new(
2071 { artist => 'fred' }, { key => 'artists' });
2073 $cd->cd_to_producer->find_or_new({ producer => $producer },
2074 { key => 'primary });
2076 Find an existing record from this resultset, based on its primary
2077 key, or a unique constraint. If none exists, instantiate a new result
2078 object and return it. The object will not be saved into your storage
2079 until you call L<DBIx::Class::Row/insert> on it.
2081 You most likely want this method when looking for existing rows using
2082 a unique constraint that is not the primary key, or looking for
2085 If you want objects to be saved immediately, use L</find_or_create> instead.
2087 B<Note>: C<find_or_new> is probably not what you want when creating a
2088 new row in a table that uses primary keys supplied by the
2089 database. Passing in a primary key column with a value of I<undef>
2090 will cause L</find> to attempt to search for a row with a value of
2097 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2098 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2099 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2102 return $self->new_result($hash);
2109 =item Arguments: \%vals
2111 =item Return Value: a L<DBIx::Class::Row> $object
2115 Attempt to create a single new row or a row with multiple related rows
2116 in the table represented by the resultset (and related tables). This
2117 will not check for duplicate rows before inserting, use
2118 L</find_or_create> to do that.
2120 To create one row for this resultset, pass a hashref of key/value
2121 pairs representing the columns of the table and the values you wish to
2122 store. If the appropriate relationships are set up, foreign key fields
2123 can also be passed an object representing the foreign row, and the
2124 value will be set to its primary key.
2126 To create related objects, pass a hashref for the value if the related
2127 item is a foreign key relationship (L<DBIx::Class::Relationship/belongs_to>),
2128 and use the name of the relationship as the key. (NOT the name of the field,
2129 necessarily). For C<has_many> and C<has_one> relationships, pass an arrayref
2130 of hashrefs containing the data for each of the rows to create in the foreign
2131 tables, again using the relationship name as the key.
2133 Instead of hashrefs of plain related data (key/value pairs), you may
2134 also pass new or inserted objects. New objects (not inserted yet, see
2135 L</new>), will be inserted into their appropriate tables.
2137 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2139 Example of creating a new row.
2141 $person_rs->create({
2142 name=>"Some Person",
2143 email=>"somebody@someplace.com"
2146 Example of creating a new row and also creating rows in a related C<has_many>
2147 or C<has_one> resultset. Note Arrayref.
2150 { artistid => 4, name => 'Manufactured Crap', cds => [
2151 { title => 'My First CD', year => 2006 },
2152 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2157 Example of creating a new row and also creating a row in a related
2158 C<belongs_to>resultset. Note Hashref.
2161 title=>"Music for Silly Walks",
2164 name=>"Silly Musician",
2171 my ($self, $attrs) = @_;
2172 $self->throw_exception( "create needs a hashref" )
2173 unless ref $attrs eq 'HASH';
2174 return $self->new_result($attrs)->insert;
2177 =head2 find_or_create
2181 =item Arguments: \%vals, \%attrs?
2183 =item Return Value: $rowobject
2187 $cd->cd_to_producer->find_or_create({ producer => $producer },
2188 { key => 'primary });
2190 Tries to find a record based on its primary key or unique constraints; if none
2191 is found, creates one and returns that instead.
2193 my $cd = $schema->resultset('CD')->find_or_create({
2195 artist => 'Massive Attack',
2196 title => 'Mezzanine',
2200 Also takes an optional C<key> attribute, to search by a specific key or unique
2201 constraint. For example:
2203 my $cd = $schema->resultset('CD')->find_or_create(
2205 artist => 'Massive Attack',
2206 title => 'Mezzanine',
2208 { key => 'cd_artist_title' }
2211 B<Note>: Because find_or_create() reads from the database and then
2212 possibly inserts based on the result, this method is subject to a race
2213 condition. Another process could create a record in the table after
2214 the find has completed and before the create has started. To avoid
2215 this problem, use find_or_create() inside a transaction.
2217 B<Note>: C<find_or_create> is probably not what you want when creating
2218 a new row in a table that uses primary keys supplied by the
2219 database. Passing in a primary key column with a value of I<undef>
2220 will cause L</find> to attempt to search for a row with a value of
2223 See also L</find> and L</update_or_create>. For information on how to declare
2224 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2228 sub find_or_create {
2230 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2231 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2232 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2235 return $self->create($hash);
2238 =head2 update_or_create
2242 =item Arguments: \%col_values, { key => $unique_constraint }?
2244 =item Return Value: $rowobject
2248 $resultset->update_or_create({ col => $val, ... });
2250 First, searches for an existing row matching one of the unique constraints
2251 (including the primary key) on the source of this resultset. If a row is
2252 found, updates it with the other given column values. Otherwise, creates a new
2255 Takes an optional C<key> attribute to search on a specific unique constraint.
2258 # In your application
2259 my $cd = $schema->resultset('CD')->update_or_create(
2261 artist => 'Massive Attack',
2262 title => 'Mezzanine',
2265 { key => 'cd_artist_title' }
2268 $cd->cd_to_producer->update_or_create({
2269 producer => $producer,
2276 If no C<key> is specified, it searches on all unique constraints defined on the
2277 source, including the primary key.
2279 If the C<key> is specified as C<primary>, it searches only on the primary key.
2281 See also L</find> and L</find_or_create>. For information on how to declare
2282 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2284 B<Note>: C<update_or_create> is probably not what you want when
2285 looking for a row in a table that uses primary keys supplied by the
2286 database, unless you actually have a key value. Passing in a primary
2287 key column with a value of I<undef> will cause L</find> to attempt to
2288 search for a row with a value of I<NULL>.
2292 sub update_or_create {
2294 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2295 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2297 my $row = $self->find($cond, $attrs);
2299 $row->update($cond);
2303 return $self->create($cond);
2306 =head2 update_or_new
2310 =item Arguments: \%col_values, { key => $unique_constraint }?
2312 =item Return Value: $rowobject
2316 $resultset->update_or_new({ col => $val, ... });
2318 First, searches for an existing row matching one of the unique constraints
2319 (including the primary key) on the source of this resultset. If a row is
2320 found, updates it with the other given column values. Otherwise, instantiate
2321 a new result object and return it. The object will not be saved into your storage
2322 until you call L<DBIx::Class::Row/insert> on it.
2324 Takes an optional C<key> attribute to search on a specific unique constraint.
2327 # In your application
2328 my $cd = $schema->resultset('CD')->update_or_new(
2330 artist => 'Massive Attack',
2331 title => 'Mezzanine',
2334 { key => 'cd_artist_title' }
2337 if ($cd->in_storage) {
2338 # the cd was updated
2341 # the cd is not yet in the database, let's insert it
2345 See also L</find>, L</find_or_create> and L<find_or_new>.
2351 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2352 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2354 my $row = $self->find( $cond, $attrs );
2355 if ( defined $row ) {
2356 $row->update($cond);
2360 return $self->new_result($cond);
2367 =item Arguments: none
2369 =item Return Value: \@cache_objects?
2373 Gets the contents of the cache for the resultset, if the cache is set.
2375 The cache is populated either by using the L</prefetch> attribute to
2376 L</search> or by calling L</set_cache>.
2388 =item Arguments: \@cache_objects
2390 =item Return Value: \@cache_objects
2394 Sets the contents of the cache for the resultset. Expects an arrayref
2395 of objects of the same class as those produced by the resultset. Note that
2396 if the cache is set the resultset will return the cached objects rather
2397 than re-querying the database even if the cache attr is not set.
2399 The contents of the cache can also be populated by using the
2400 L</prefetch> attribute to L</search>.
2405 my ( $self, $data ) = @_;
2406 $self->throw_exception("set_cache requires an arrayref")
2407 if defined($data) && (ref $data ne 'ARRAY');
2408 $self->{all_cache} = $data;
2415 =item Arguments: none
2417 =item Return Value: []
2421 Clears the cache for the resultset.
2426 shift->set_cache(undef);
2429 =head2 related_resultset
2433 =item Arguments: $relationship_name
2435 =item Return Value: $resultset
2439 Returns a related resultset for the supplied relationship name.
2441 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2445 sub related_resultset {
2446 my ($self, $rel) = @_;
2448 $self->{related_resultsets} ||= {};
2449 return $self->{related_resultsets}{$rel} ||= do {
2450 my $rel_obj = $self->result_source->relationship_info($rel);
2452 $self->throw_exception(
2453 "search_related: result source '" . $self->result_source->source_name .
2454 "' has no such relationship $rel")
2457 my ($from,$seen) = $self->_resolve_from($rel);
2459 my $join_count = $seen->{$rel};
2460 my $alias = ($join_count > 1 ? join('_', $rel, $join_count) : $rel);
2462 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2463 my %attrs = %{$self->{attrs}||{}};
2464 delete @attrs{qw(result_class alias)};
2468 if (my $cache = $self->get_cache) {
2469 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2470 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
2475 my $rel_source = $self->result_source->related_source($rel);
2479 # The reason we do this now instead of passing the alias to the
2480 # search_rs below is that if you wrap/overload resultset on the
2481 # source you need to know what alias it's -going- to have for things
2482 # to work sanely (e.g. RestrictWithObject wants to be able to add
2483 # extra query restrictions, and these may need to be $alias.)
2485 my $attrs = $rel_source->resultset_attributes;
2486 local $attrs->{alias} = $alias;
2488 $rel_source->resultset
2496 where => $self->{cond},
2501 $new->set_cache($new_cache) if $new_cache;
2506 =head2 current_source_alias
2510 =item Arguments: none
2512 =item Return Value: $source_alias
2516 Returns the current table alias for the result source this resultset is built
2517 on, that will be used in the SQL query. Usually it is C<me>.
2519 Currently the source alias that refers to the result set returned by a
2520 L</search>/L</find> family method depends on how you got to the resultset: it's
2521 C<me> by default, but eg. L</search_related> aliases it to the related result
2522 source name (and keeps C<me> referring to the original result set). The long
2523 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
2524 (and make this method unnecessary).
2526 Thus it's currently necessary to use this method in predefined queries (see
2527 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
2528 source alias of the current result set:
2530 # in a result set class
2532 my ($self, $user) = @_;
2534 my $me = $self->current_source_alias;
2536 return $self->search(
2537 "$me.modified" => $user->id,
2543 sub current_source_alias {
2546 return ($self->{attrs} || {})->{alias} || 'me';
2549 # This code is called by search_related, and makes sure there
2550 # is clear separation between the joins before, during, and
2551 # after the relationship. This information is needed later
2552 # in order to properly resolve prefetch aliases (any alias
2553 # with a relation_chain_depth less than the depth of the
2554 # current prefetch is not considered)
2556 my ($self, $extra_join) = @_;
2557 my $source = $self->result_source;
2558 my $attrs = $self->{attrs};
2564 -source_handle => $source->handle,
2565 -alias => $attrs->{alias},
2566 $attrs->{alias} => $source->from,
2570 my $seen = { %{$attrs->{seen_join} || {} } };
2572 # we need to take the prefetch the attrs into account before we
2573 # ->_resolve_join as otherwise they get lost - captainL
2574 my $merged = $self->_merge_attr( $attrs->{join}, $attrs->{prefetch} );
2576 push @$from, $source->_resolve_join($merged, $attrs->{alias}, $seen) if ($merged);
2578 ++$seen->{-relation_chain_depth};
2580 push @$from, $source->_resolve_join($extra_join, $attrs->{alias}, $seen);
2582 ++$seen->{-relation_chain_depth};
2584 return ($from,$seen);
2587 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
2588 sub _resolved_attrs_copy {
2590 return { %{$self->_resolved_attrs (@_)} };
2593 sub _resolved_attrs {
2595 return $self->{_attrs} if $self->{_attrs};
2597 my $attrs = { %{ $self->{attrs} || {} } };
2598 my $source = $self->result_source;
2599 my $alias = $attrs->{alias};
2601 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
2604 # build columns (as long as select isn't set) into a set of as/select hashes
2605 unless ( $attrs->{select} ) {
2607 ( ref($_) eq 'HASH' )
2611 /^\Q${alias}.\E(.+)$/
2622 } ( ref($attrs->{columns}) eq 'ARRAY' ) ? @{ delete $attrs->{columns}} : (delete $attrs->{columns} || $source->columns );
2624 # add the additional columns on
2625 foreach ( 'include_columns', '+columns' ) {
2626 push @colbits, map {
2627 ( ref($_) eq 'HASH' )
2629 : { ( split( /\./, $_ ) )[-1] => ( /\./ ? $_ : "${alias}.$_" ) }
2630 } ( ref($attrs->{$_}) eq 'ARRAY' ) ? @{ delete $attrs->{$_} } : delete $attrs->{$_} if ( $attrs->{$_} );
2633 # start with initial select items
2634 if ( $attrs->{select} ) {
2636 ( ref $attrs->{select} eq 'ARRAY' )
2637 ? [ @{ $attrs->{select} } ]
2638 : [ $attrs->{select} ];
2642 ref $attrs->{as} eq 'ARRAY'
2643 ? [ @{ $attrs->{as} } ]
2646 : [ map { m/^\Q${alias}.\E(.+)$/ ? $1 : $_ } @{ $attrs->{select} } ]
2651 # otherwise we intialise select & as to empty
2652 $attrs->{select} = [];
2656 # now add colbits to select/as
2657 push( @{ $attrs->{select} }, map { values( %{$_} ) } @colbits );
2658 push( @{ $attrs->{as} }, map { keys( %{$_} ) } @colbits );
2661 if ( $adds = delete $attrs->{'+select'} ) {
2662 $adds = [$adds] unless ref $adds eq 'ARRAY';
2664 @{ $attrs->{select} },
2665 map { /\./ || ref $_ ? $_ : "${alias}.$_" } @$adds
2668 if ( $adds = delete $attrs->{'+as'} ) {
2669 $adds = [$adds] unless ref $adds eq 'ARRAY';
2670 push( @{ $attrs->{as} }, @$adds );
2673 $attrs->{from} ||= [ {
2674 -source_handle => $source->handle,
2675 -alias => $self->{attrs}{alias},
2676 $self->{attrs}{alias} => $source->from,
2679 if ( $attrs->{join} || $attrs->{prefetch} ) {
2681 $self->throw_exception ('join/prefetch can not be used with a literal scalarref {from}')
2682 if ref $attrs->{from} ne 'ARRAY';
2684 my $join = delete $attrs->{join} || {};
2686 if ( defined $attrs->{prefetch} ) {
2687 $join = $self->_merge_attr( $join, $attrs->{prefetch} );
2690 $attrs->{from} = # have to copy here to avoid corrupting the original
2692 @{ $attrs->{from} },
2693 $source->_resolve_join(
2694 $join, $alias, { %{ $attrs->{seen_join} || {} } }
2699 if ( $attrs->{order_by} ) {
2700 $attrs->{order_by} = (
2701 ref( $attrs->{order_by} ) eq 'ARRAY'
2702 ? [ @{ $attrs->{order_by} } ]
2703 : [ $attrs->{order_by} ]
2707 $attrs->{order_by} = [];
2710 # If the order_by is otherwise empty - we will use this for TOP limit
2711 # emulation and the like.
2712 # Although this is needed only if the order_by is not defined, it is
2713 # actually cheaper to just populate this rather than properly examining
2714 # order_by (stuf like [ {} ] and the like)
2715 $attrs->{_virtual_order_by} = [ $self->result_source->primary_columns ];
2718 $attrs->{collapse} ||= {};
2719 if ( my $prefetch = delete $attrs->{prefetch} ) {
2720 $prefetch = $self->_merge_attr( {}, $prefetch );
2722 my $prefetch_ordering = [];
2724 my $join_map = $self->_joinpath_aliases ($attrs->{from}, $attrs->{seen_join});
2727 $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
2729 push( @{ $attrs->{select} }, map { $_->[0] } @prefetch );
2730 push( @{ $attrs->{as} }, map { $_->[1] } @prefetch );
2732 push( @{ $attrs->{order_by} }, @$prefetch_ordering );
2733 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
2737 if (delete $attrs->{distinct}) {
2738 $attrs->{group_by} ||= [ grep { !ref($_) || (ref($_) ne 'HASH') } @{$attrs->{select}} ];
2741 # if both page and offset are specified, produce a combined offset
2742 # even though it doesn't make much sense, this is what pre 081xx has
2744 if (my $page = delete $attrs->{page}) {
2745 $attrs->{offset} = ($attrs->{rows} * ($page - 1)) +
2746 ($attrs->{offset} || 0);
2749 return $self->{_attrs} = $attrs;
2752 sub _joinpath_aliases {
2753 my ($self, $fromspec, $seen) = @_;
2756 return $paths unless ref $fromspec eq 'ARRAY';
2758 for my $j (@$fromspec) {
2760 next if ref $j ne 'ARRAY';
2761 next if $j->[0]{-relation_chain_depth} < ( $seen->{-relation_chain_depth} || 0);
2764 $p = $p->{$_} ||= {} for @{$j->[0]{-join_path}};
2765 push @{$p->{-join_aliases} }, $j->[0]{-alias};
2772 my ($self, $attr) = @_;
2774 if (ref $attr eq 'HASH') {
2775 return $self->_rollout_hash($attr);
2776 } elsif (ref $attr eq 'ARRAY') {
2777 return $self->_rollout_array($attr);
2783 sub _rollout_array {
2784 my ($self, $attr) = @_;
2787 foreach my $element (@{$attr}) {
2788 if (ref $element eq 'HASH') {
2789 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
2790 } elsif (ref $element eq 'ARRAY') {
2791 # XXX - should probably recurse here
2792 push( @rolled_array, @{$self->_rollout_array($element)} );
2794 push( @rolled_array, $element );
2797 return \@rolled_array;
2801 my ($self, $attr) = @_;
2804 foreach my $key (keys %{$attr}) {
2805 push( @rolled_array, { $key => $attr->{$key} } );
2807 return \@rolled_array;
2810 sub _calculate_score {
2811 my ($self, $a, $b) = @_;
2813 if (ref $b eq 'HASH') {
2814 my ($b_key) = keys %{$b};
2815 if (ref $a eq 'HASH') {
2816 my ($a_key) = keys %{$a};
2817 if ($a_key eq $b_key) {
2818 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
2823 return ($a eq $b_key) ? 1 : 0;
2826 if (ref $a eq 'HASH') {
2827 my ($a_key) = keys %{$a};
2828 return ($b eq $a_key) ? 1 : 0;
2830 return ($b eq $a) ? 1 : 0;
2836 my ($self, $orig, $import) = @_;
2838 return $import unless defined($orig);
2839 return $orig unless defined($import);
2841 $orig = $self->_rollout_attr($orig);
2842 $import = $self->_rollout_attr($import);
2845 foreach my $import_element ( @{$import} ) {
2846 # find best candidate from $orig to merge $b_element into
2847 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
2848 foreach my $orig_element ( @{$orig} ) {
2849 my $score = $self->_calculate_score( $orig_element, $import_element );
2850 if ($score > $best_candidate->{score}) {
2851 $best_candidate->{position} = $position;
2852 $best_candidate->{score} = $score;
2856 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
2858 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
2859 push( @{$orig}, $import_element );
2861 my $orig_best = $orig->[$best_candidate->{position}];
2862 # merge orig_best and b_element together and replace original with merged
2863 if (ref $orig_best ne 'HASH') {
2864 $orig->[$best_candidate->{position}] = $import_element;
2865 } elsif (ref $import_element eq 'HASH') {
2866 my ($key) = keys %{$orig_best};
2867 $orig->[$best_candidate->{position}] = { $key => $self->_merge_attr($orig_best->{$key}, $import_element->{$key}) };
2870 $seen_keys->{$import_key} = 1; # don't merge the same key twice
2880 $self->_source_handle($_[0]->handle);
2882 $self->_source_handle->resolve;
2886 =head2 throw_exception
2888 See L<DBIx::Class::Schema/throw_exception> for details.
2892 sub throw_exception {
2894 if (ref $self && $self->_source_handle->schema) {
2895 $self->_source_handle->schema->throw_exception(@_)
2902 # XXX: FIXME: Attributes docs need clearing up
2906 Attributes are used to refine a ResultSet in various ways when
2907 searching for data. They can be passed to any method which takes an
2908 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
2911 These are in no particular order:
2917 =item Value: ( $order_by | \@order_by | \%order_by )
2921 Which column(s) to order the results by. If a single column name, or
2922 an arrayref of names is supplied, the argument is passed through
2923 directly to SQL. The hashref syntax allows for connection-agnostic
2924 specification of ordering direction:
2926 For descending order:
2928 order_by => { -desc => [qw/col1 col2 col3/] }
2930 For explicit ascending order:
2932 order_by => { -asc => 'col' }
2934 The old scalarref syntax (i.e. order_by => \'year DESC') is still
2935 supported, although you are strongly encouraged to use the hashref
2936 syntax as outlined above.
2942 =item Value: \@columns
2946 Shortcut to request a particular set of columns to be retrieved. Each
2947 column spec may be a string (a table column name), or a hash (in which
2948 case the key is the C<as> value, and the value is used as the C<select>
2949 expression). Adds C<me.> onto the start of any column without a C<.> in
2950 it and sets C<select> from that, then auto-populates C<as> from
2951 C<select> as normal. (You may also use the C<cols> attribute, as in
2952 earlier versions of DBIC.)
2958 =item Value: \@columns
2962 Indicates additional columns to be selected from storage. Works the same
2963 as L</columns> but adds columns to the selection. (You may also use the
2964 C<include_columns> attribute, as in earlier versions of DBIC). For
2967 $schema->resultset('CD')->search(undef, {
2968 '+columns' => ['artist.name'],
2972 would return all CDs and include a 'name' column to the information
2973 passed to object inflation. Note that the 'artist' is the name of the
2974 column (or relationship) accessor, and 'name' is the name of the column
2975 accessor in the related table.
2977 =head2 include_columns
2981 =item Value: \@columns
2985 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
2991 =item Value: \@select_columns
2995 Indicates which columns should be selected from the storage. You can use
2996 column names, or in the case of RDBMS back ends, function or stored procedure
2999 $rs = $schema->resultset('Employee')->search(undef, {
3002 { count => 'employeeid' },
3007 When you use function/stored procedure names and do not supply an C<as>
3008 attribute, the column names returned are storage-dependent. E.g. MySQL would
3009 return a column named C<count(employeeid)> in the above example.
3015 Indicates additional columns to be selected from storage. Works the same as
3016 L</select> but adds columns to the selection.
3024 Indicates additional column names for those added via L</+select>. See L</as>.
3032 =item Value: \@inflation_names
3036 Indicates column names for object inflation. That is, C<as>
3037 indicates the name that the column can be accessed as via the
3038 C<get_column> method (or via the object accessor, B<if one already
3039 exists>). It has nothing to do with the SQL code C<SELECT foo AS bar>.
3041 The C<as> attribute is used in conjunction with C<select>,
3042 usually when C<select> contains one or more function or stored
3045 $rs = $schema->resultset('Employee')->search(undef, {
3048 { count => 'employeeid' }
3050 as => ['name', 'employee_count'],
3053 my $employee = $rs->first(); # get the first Employee
3055 If the object against which the search is performed already has an accessor
3056 matching a column name specified in C<as>, the value can be retrieved using
3057 the accessor as normal:
3059 my $name = $employee->name();
3061 If on the other hand an accessor does not exist in the object, you need to
3062 use C<get_column> instead:
3064 my $employee_count = $employee->get_column('employee_count');
3066 You can create your own accessors if required - see
3067 L<DBIx::Class::Manual::Cookbook> for details.
3069 Please note: This will NOT insert an C<AS employee_count> into the SQL
3070 statement produced, it is used for internal access only. Thus
3071 attempting to use the accessor in an C<order_by> clause or similar
3072 will fail miserably.
3074 To get around this limitation, you can supply literal SQL to your
3075 C<select> attibute that contains the C<AS alias> text, eg:
3077 select => [\'myfield AS alias']
3083 =item Value: ($rel_name | \@rel_names | \%rel_names)
3087 Contains a list of relationships that should be joined for this query. For
3090 # Get CDs by Nine Inch Nails
3091 my $rs = $schema->resultset('CD')->search(
3092 { 'artist.name' => 'Nine Inch Nails' },
3093 { join => 'artist' }
3096 Can also contain a hash reference to refer to the other relation's relations.
3099 package MyApp::Schema::Track;
3100 use base qw/DBIx::Class/;
3101 __PACKAGE__->table('track');
3102 __PACKAGE__->add_columns(qw/trackid cd position title/);
3103 __PACKAGE__->set_primary_key('trackid');
3104 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3107 # In your application
3108 my $rs = $schema->resultset('Artist')->search(
3109 { 'track.title' => 'Teardrop' },
3111 join => { cd => 'track' },
3112 order_by => 'artist.name',
3116 You need to use the relationship (not the table) name in conditions,
3117 because they are aliased as such. The current table is aliased as "me", so
3118 you need to use me.column_name in order to avoid ambiguity. For example:
3120 # Get CDs from 1984 with a 'Foo' track
3121 my $rs = $schema->resultset('CD')->search(
3124 'tracks.name' => 'Foo'
3126 { join => 'tracks' }
3129 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3130 similarly for a third time). For e.g.
3132 my $rs = $schema->resultset('Artist')->search({
3133 'cds.title' => 'Down to Earth',
3134 'cds_2.title' => 'Popular',
3136 join => [ qw/cds cds/ ],
3139 will return a set of all artists that have both a cd with title 'Down
3140 to Earth' and a cd with title 'Popular'.
3142 If you want to fetch related objects from other tables as well, see C<prefetch>
3145 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3151 =item Value: ($rel_name | \@rel_names | \%rel_names)
3155 Contains one or more relationships that should be fetched along with
3156 the main query (when they are accessed afterwards the data will
3157 already be available, without extra queries to the database). This is
3158 useful for when you know you will need the related objects, because it
3159 saves at least one query:
3161 my $rs = $schema->resultset('Tag')->search(
3170 The initial search results in SQL like the following:
3172 SELECT tag.*, cd.*, artist.* FROM tag
3173 JOIN cd ON tag.cd = cd.cdid
3174 JOIN artist ON cd.artist = artist.artistid
3176 L<DBIx::Class> has no need to go back to the database when we access the
3177 C<cd> or C<artist> relationships, which saves us two SQL statements in this
3180 Simple prefetches will be joined automatically, so there is no need
3181 for a C<join> attribute in the above search.
3183 C<prefetch> can be used with the following relationship types: C<belongs_to>,
3184 C<has_one> (or if you're using C<add_relationship>, any relationship declared
3185 with an accessor type of 'single' or 'filter'). A more complex example that
3186 prefetches an artists cds, the tracks on those cds, and the tags associted
3187 with that artist is given below (assuming many-to-many from artists to tags):
3189 my $rs = $schema->resultset('Artist')->search(
3193 { cds => 'tracks' },
3194 { artist_tags => 'tags' }
3200 B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
3201 attributes will be ignored.
3211 Makes the resultset paged and specifies the page to retrieve. Effectively
3212 identical to creating a non-pages resultset and then calling ->page($page)
3215 If L<rows> attribute is not specified it defualts to 10 rows per page.
3217 When you have a paged resultset, L</count> will only return the number
3218 of rows in the page. To get the total, use the L</pager> and call
3219 C<total_entries> on it.
3229 Specifes the maximum number of rows for direct retrieval or the number of
3230 rows per page if the page attribute or method is used.
3236 =item Value: $offset
3240 Specifies the (zero-based) row number for the first row to be returned, or the
3241 of the first row of the first page if paging is used.
3247 =item Value: \@columns
3251 A arrayref of columns to group by. Can include columns of joined tables.
3253 group_by => [qw/ column1 column2 ... /]
3259 =item Value: $condition
3263 HAVING is a select statement attribute that is applied between GROUP BY and
3264 ORDER BY. It is applied to the after the grouping calculations have been
3267 having => { 'count(employee)' => { '>=', 100 } }
3273 =item Value: (0 | 1)
3277 Set to 1 to group by all columns.
3283 Adds to the WHERE clause.
3285 # only return rows WHERE deleted IS NULL for all searches
3286 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
3288 Can be overridden by passing C<{ where => undef }> as an attribute
3295 Set to 1 to cache search results. This prevents extra SQL queries if you
3296 revisit rows in your ResultSet:
3298 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
3300 while( my $artist = $resultset->next ) {
3304 $rs->first; # without cache, this would issue a query
3306 By default, searches are not cached.
3308 For more examples of using these attributes, see
3309 L<DBIx::Class::Manual::Cookbook>.
3315 =item Value: \@from_clause
3319 The C<from> attribute gives you manual control over the C<FROM> clause of SQL
3320 statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
3323 NOTE: Use this on your own risk. This allows you to shoot off your foot!
3325 C<join> will usually do what you need and it is strongly recommended that you
3326 avoid using C<from> unless you cannot achieve the desired result using C<join>.
3327 And we really do mean "cannot", not just tried and failed. Attempting to use
3328 this because you're having problems with C<join> is like trying to use x86
3329 ASM because you've got a syntax error in your C. Trust us on this.
3331 Now, if you're still really, really sure you need to use this (and if you're
3332 not 100% sure, ask the mailing list first), here's an explanation of how this
3335 The syntax is as follows -
3338 { <alias1> => <table1> },
3340 { <alias2> => <table2>, -join_type => 'inner|left|right' },
3341 [], # nested JOIN (optional)
3342 { <table1.column1> => <table2.column2>, ... (more conditions) },
3344 # More of the above [ ] may follow for additional joins
3351 ON <table1.column1> = <table2.column2>
3352 <more joins may follow>
3354 An easy way to follow the examples below is to remember the following:
3356 Anything inside "[]" is a JOIN
3357 Anything inside "{}" is a condition for the enclosing JOIN
3359 The following examples utilize a "person" table in a family tree application.
3360 In order to express parent->child relationships, this table is self-joined:
3362 # Person->belongs_to('father' => 'Person');
3363 # Person->belongs_to('mother' => 'Person');
3365 C<from> can be used to nest joins. Here we return all children with a father,
3366 then search against all mothers of those children:
3368 $rs = $schema->resultset('Person')->search(
3371 alias => 'mother', # alias columns in accordance with "from"
3373 { mother => 'person' },
3376 { child => 'person' },
3378 { father => 'person' },
3379 { 'father.person_id' => 'child.father_id' }
3382 { 'mother.person_id' => 'child.mother_id' }
3389 # SELECT mother.* FROM person mother
3392 # JOIN person father
3393 # ON ( father.person_id = child.father_id )
3395 # ON ( mother.person_id = child.mother_id )
3397 The type of any join can be controlled manually. To search against only people
3398 with a father in the person table, we could explicitly use C<INNER JOIN>:
3400 $rs = $schema->resultset('Person')->search(
3403 alias => 'child', # alias columns in accordance with "from"
3405 { child => 'person' },
3407 { father => 'person', -join_type => 'inner' },
3408 { 'father.id' => 'child.father_id' }
3415 # SELECT child.* FROM person child
3416 # INNER JOIN person father ON child.father_id = father.id
3418 You can select from a subquery by passing a resultset to from as follows.
3420 $schema->resultset('Artist')->search(
3422 { alias => 'artist2',
3423 from => [ { artist2 => $artist_rs->as_query } ],
3426 # and you'll get sql like this..
3427 # SELECT artist2.artistid, artist2.name, artist2.rank, artist2.charfield FROM
3428 # ( SELECT me.artistid, me.name, me.rank, me.charfield FROM artists me ) artist2
3430 If you need to express really complex joins, you
3431 can supply literal SQL to C<from> via a scalar reference. In this case
3432 the contents of the scalar will replace the table name associated with the
3435 WARNING: This technique might very well not work as expected on chained
3436 searches - you have been warned.
3438 # Assuming the Event resultsource is defined as:
3440 MySchema::Event->add_columns (
3443 is_auto_increment => 1,
3452 MySchema::Event->set_primary_key ('sequence');
3454 # This will get back the latest event for every location. The column
3455 # selector is still provided by DBIC, all we do is add a JOIN/WHERE
3456 # combo to limit the resultset
3458 $rs = $schema->resultset('Event');
3459 $table = $rs->result_source->name;
3460 $latest = $rs->search (
3463 (SELECT e1.* FROM $table e1
3465 ON e1.location = e2.location
3466 AND e1.sequence < e2.sequence
3467 WHERE e2.sequence is NULL
3472 # Equivalent SQL (with the DBIC chunks added):
3474 SELECT me.sequence, me.location, me.type FROM
3475 (SELECT e1.* FROM events e1
3477 ON e1.location = e2.location
3478 AND e1.sequence < e2.sequence
3479 WHERE e2.sequence is NULL
3486 =item Value: ( 'update' | 'shared' )
3490 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT