1 package DBIx::Class::ResultSet;
5 use base qw/DBIx::Class/;
6 use Carp::Clan qw/^DBIx::Class/;
7 use DBIx::Class::Exception;
10 use DBIx::Class::ResultSetColumn;
11 use DBIx::Class::ResultSourceHandle;
13 use Scalar::Util qw/blessed weaken/;
22 __PACKAGE__->mk_group_accessors('simple' => qw/_result_class _source_handle/);
26 DBIx::Class::ResultSet - Represents a query used for fetching a set of results.
30 my $users_rs = $schema->resultset('User');
31 while( $user = $users_rs->next) {
32 print $user->username;
35 my $registered_users_rs = $schema->resultset('User')->search({ registered => 1 });
36 my @cds_in_2005 = $schema->resultset('CD')->search({ year => 2005 })->all();
40 A ResultSet is an object which stores a set of conditions representing
41 a query. It is the backbone of DBIx::Class (i.e. the really
42 important/useful bit).
44 No SQL is executed on the database when a ResultSet is created, it
45 just stores all the conditions needed to create the query.
47 A basic ResultSet representing the data of an entire table is returned
48 by calling C<resultset> on a L<DBIx::Class::Schema> and passing in a
49 L<Source|DBIx::Class::Manual::Glossary/Source> name.
51 my $users_rs = $schema->resultset('User');
53 A new ResultSet is returned from calling L</search> on an existing
54 ResultSet. The new one will contain all the conditions of the
55 original, plus any new conditions added in the C<search> call.
57 A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
58 can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
61 The query that the ResultSet represents is B<only> executed against
62 the database when these methods are called:
63 L</find>, L</next>, L</all>, L</first>, L</single>, L</count>.
65 If a resultset is used in a numeric context it returns the L</count>.
66 However, if it is used in a boolean context it is B<always> true. So if
67 you want to check if a resultset has any results, you must use C<if $rs
72 =head2 Chaining resultsets
74 Let's say you've got a query that needs to be run to return some data
75 to the user. But, you have an authorization system in place that
76 prevents certain users from seeing certain information. So, you want
77 to construct the basic query in one method, but add constraints to it in
82 my $request = $self->get_request; # Get a request object somehow.
83 my $schema = $self->get_schema; # Get the DBIC schema object somehow.
85 my $cd_rs = $schema->resultset('CD')->search({
86 title => $request->param('title'),
87 year => $request->param('year'),
90 $self->apply_security_policy( $cd_rs );
95 sub apply_security_policy {
104 =head3 Resolving conditions and attributes
106 When a resultset is chained from another resultset, conditions and
107 attributes with the same keys need resolving.
109 L</join>, L</prefetch>, L</+select>, L</+as> attributes are merged
110 into the existing ones from the original resultset.
112 The L</where> and L</having> attributes, and any search conditions, are
113 merged with an SQL C<AND> to the existing condition from the original
116 All other attributes are overridden by any new ones supplied in the
119 =head2 Multiple queries
121 Since a resultset just defines a query, you can do all sorts of
122 things with it with the same object.
124 # Don't hit the DB yet.
125 my $cd_rs = $schema->resultset('CD')->search({
126 title => 'something',
130 # Each of these hits the DB individually.
131 my $count = $cd_rs->count;
132 my $most_recent = $cd_rs->get_column('date_released')->max();
133 my @records = $cd_rs->all;
135 And it's not just limited to SELECT statements.
141 $cd_rs->create({ artist => 'Fred' });
143 Which is the same as:
145 $schema->resultset('CD')->create({
146 title => 'something',
151 See: L</search>, L</count>, L</get_column>, L</all>, L</create>.
159 =item Arguments: $source, \%$attrs
161 =item Return Value: $rs
165 The resultset constructor. Takes a source object (usually a
166 L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
167 L</ATTRIBUTES> below). Does not perform any queries -- these are
168 executed as needed by the other methods.
170 Generally you won't need to construct a resultset manually. You'll
171 automatically get one from e.g. a L</search> called in scalar context:
173 my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
175 IMPORTANT: If called on an object, proxies to new_result instead so
177 my $cd = $schema->resultset('CD')->new({ title => 'Spoon' });
179 will return a CD object, not a ResultSet.
185 return $class->new_result(@_) if ref $class;
187 my ($source, $attrs) = @_;
188 $source = $source->handle
189 unless $source->isa('DBIx::Class::ResultSourceHandle');
190 $attrs = { %{$attrs||{}} };
192 if ($attrs->{page}) {
193 $attrs->{rows} ||= 10;
196 $attrs->{alias} ||= 'me';
198 # Creation of {} and bless separated to mitigate RH perl bug
199 # see https://bugzilla.redhat.com/show_bug.cgi?id=196836
201 _source_handle => $source,
202 cond => $attrs->{where},
210 $attrs->{result_class} || $source->resolve->result_class
220 =item Arguments: $cond, \%attrs?
222 =item Return Value: $resultset (scalar context), @row_objs (list context)
226 my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001"
227 my $new_rs = $cd_rs->search({ year => 2005 });
229 my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]);
230 # year = 2005 OR year = 2004
232 If you need to pass in additional attributes but no additional condition,
233 call it as C<search(undef, \%attrs)>.
235 # "SELECT name, artistid FROM $artist_table"
236 my @all_artists = $schema->resultset('Artist')->search(undef, {
237 columns => [qw/name artistid/],
240 For a list of attributes that can be passed to C<search>, see
241 L</ATTRIBUTES>. For more examples of using this function, see
242 L<Searching|DBIx::Class::Manual::Cookbook/Searching>. For a complete
243 documentation for the first argument, see L<SQL::Abstract>.
245 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
251 my $rs = $self->search_rs( @_ );
252 return (wantarray ? $rs->all : $rs);
259 =item Arguments: $cond, \%attrs?
261 =item Return Value: $resultset
265 This method does the same exact thing as search() except it will
266 always return a resultset, even in list context.
273 # Special-case handling for (undef, undef).
274 if ( @_ == 2 && !defined $_[1] && !defined $_[0] ) {
279 $call_attrs = pop(@_) if @_ > 1 and ref $_[-1] eq 'HASH';
281 # see if we can keep the cache (no $rs changes)
283 my %safe = (alias => 1, cache => 1);
284 if ( ! List::Util::first { !$safe{$_} } keys %$call_attrs and (
287 ref $_[0] eq 'HASH' && ! keys %{$_[0]}
289 ref $_[0] eq 'ARRAY' && ! @{$_[0]}
291 $cache = $self->get_cache;
294 my $old_attrs = { %{$self->{attrs}} };
295 my $old_having = delete $old_attrs->{having};
296 my $old_where = delete $old_attrs->{where};
298 # reset the selector list
299 if (List::Util::first { exists $call_attrs->{$_} } qw{columns select as}) {
300 delete @{$old_attrs}{qw{select as columns +select +as +columns include_columns}};
303 my $new_attrs = { %{$old_attrs}, %{$call_attrs} };
305 # merge new attrs into inherited
306 foreach my $key (qw/join prefetch +select +as +columns include_columns bind/) {
307 next unless exists $call_attrs->{$key};
308 $new_attrs->{$key} = $self->_merge_attr($old_attrs->{$key}, $call_attrs->{$key});
311 # rip apart the rest of @_, parse a condition
314 if (ref $_[0] eq 'HASH') {
315 (keys %{$_[0]}) ? $_[0] : undef
321 $self->throw_exception('Odd number of arguments to search')
329 for ($old_where, $call_cond) {
331 $new_attrs->{where} = $self->_stack_cond (
332 $_, $new_attrs->{where}
337 if (defined $old_having) {
338 $new_attrs->{having} = $self->_stack_cond (
339 $old_having, $new_attrs->{having}
343 my $rs = (ref $self)->new($self->result_source, $new_attrs);
345 $rs->set_cache($cache) if ($cache);
351 my ($self, $left, $right) = @_;
352 if (defined $left xor defined $right) {
353 return defined $left ? $left : $right;
355 elsif (defined $left) {
356 return { -and => [ map
357 { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
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: \%columns_values | @pk_values, \%attrs?
413 =item Return Value: $row_object | undef
417 Finds and returns a single row based on supplied criteria. Takes either a
418 hashref with the same format as L</create> (including inference of foreign
419 keys from related objects), or a list of primary key values in the same
420 order as the L<primary columns|DBIx::Class::ResultSource/primary_columns>
421 declaration on the L</result_source>.
423 In either case an attempt is made to combine conditions already existing on
424 the resultset with the condition passed to this method.
426 To aid with preparing the correct query for the storage you may supply the
427 C<key> attribute, which is the name of a
428 L<unique constraint|DBIx::Class::ResultSource/add_unique_constraint> (the
429 unique constraint corresponding to the
430 L<primary columns|DBIx::Class::ResultSource/primary_columns> is always named
431 C<primary>). If the C<key> attribute has been supplied, and DBIC is unable
432 to construct a query that satisfies the named unique constraint fully (
433 non-NULL values for each column member of the constraint) an exception is
436 If no C<key> is specified, the search is carried over all unique constraints
437 which are fully defined by the available condition.
439 If no such constraint is found, C<find> currently defaults to a simple
440 C<< search->(\%column_values) >> which may or may not do what you expect.
441 Note that this fallback behavior may be deprecated in further versions. If
442 you need to search with arbitrary conditions - use L</search>.
444 In addition to C<key>, L</find> recognizes and applies standard
445 L<resultset attributes|/ATTRIBUTES> in the same way as L</search> does.
447 If the resulting query produces more than one row, a warning to the effect is
448 issued, though only the first row is constructed and returned as C<$row_object>
450 Note that if you have extra concerns about the correctness of the resulting
451 query you need to specify the C<key> attribute and supply the entire condition
452 as an argument to find (since it is not always possible to perform the
453 combination of the resultset condition with the supplied one, especially if
454 the resultset condition contains literal sql).
456 For example, to find a row by its primary key:
458 my $cd = $schema->resultset('CD')->find(5);
460 You can also find a row by a specific unique constraint:
462 my $cd = $schema->resultset('CD')->find(
464 artist => 'Massive Attack',
465 title => 'Mezzanine',
467 { key => 'cd_artist_title' }
470 See also L</find_or_create> and L</update_or_create>.
476 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
478 my $rsrc = $self->result_source;
480 # Parse out the condition from input
482 if (ref $_[0] eq 'HASH') {
483 $call_cond = { %{$_[0]} };
486 my $constraint = exists $attrs->{key} ? $attrs->{key} : 'primary';
487 my @c_cols = $rsrc->unique_constraint_columns($constraint);
489 $self->throw_exception(
490 "No constraint columns, maybe a malformed '$constraint' constraint?"
493 $self->throw_exception (
494 'find() expects either a column/value hashref, or a list of values '
495 . "corresponding to the columns of the specified unique constraint '$constraint'"
496 ) unless @c_cols == @_;
499 @{$call_cond}{@c_cols} = @_;
503 for my $key (keys %$call_cond) {
505 my $keyref = ref($call_cond->{$key})
507 my $relinfo = $rsrc->relationship_info($key)
509 my $val = delete $call_cond->{$key};
511 next if $keyref eq 'ARRAY'; # has_many for multi_create
513 my $rel_q = $rsrc->_resolve_condition(
514 $relinfo->{cond}, $val, $key
516 die "Can't handle complex relationship conditions in find" if ref($rel_q) ne 'HASH';
517 @related{keys %$rel_q} = values %$rel_q;
521 # relationship conditions take precedence (?)
522 @{$call_cond}{keys %related} = values %related;
524 my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias};
526 if (exists $attrs->{key}) {
527 $final_cond = $self->_qualify_cond_columns (
529 $self->_build_unique_cond (
537 elsif ($self->{attrs}{accessor} and $self->{attrs}{accessor} eq 'single') {
538 # This means that we got here after a merger of relationship conditions
539 # in ::Relationship::Base::search_related (the row method), and furthermore
540 # the relationship is of the 'single' type. This means that the condition
541 # provided by the relationship (already attached to $self) is sufficient,
542 # as there can be only one row in the database that would satisfy the
546 # no key was specified - fall down to heuristics mode:
547 # run through all unique queries registered on the resultset, and
548 # 'OR' all qualifying queries together
549 my (@unique_queries, %seen_column_combinations);
550 for my $c_name ($rsrc->unique_constraint_names) {
551 next if $seen_column_combinations{
552 join "\x00", sort $rsrc->unique_constraint_columns($c_name)
555 push @unique_queries, try {
556 $self->_build_unique_cond ($c_name, $call_cond)
560 $final_cond = @unique_queries
561 ? [ map { $self->_qualify_cond_columns($_, $alias) } @unique_queries ]
562 : $self->_qualify_cond_columns($call_cond, $alias)
566 # Run the query, passing the result_class since it should propagate for find
567 my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
568 if (keys %{$rs->_resolved_attrs->{collapse}}) {
570 carp "Query returned more than one row" if $rs->next;
578 sub _qualify_cond_columns {
579 my ($self, $cond, $alias) = @_;
581 my %aliased = %$cond;
582 for (keys %aliased) {
583 $aliased{"$alias.$_"} = delete $aliased{$_}
590 sub _build_unique_cond {
591 my ($self, $constraint_name, $extra_cond) = @_;
593 my @c_cols = $self->result_source->unique_constraint_columns($constraint_name);
595 # combination may fail if $self->{cond} is non-trivial
596 my ($final_cond) = try {
597 $self->_merge_with_rscond ($extra_cond)
602 # trim out everything not in $columns
603 $final_cond = { map { $_ => $final_cond->{$_} } @c_cols };
605 if (my @missing = grep { ! defined $final_cond->{$_} } (@c_cols) ) {
606 $self->throw_exception( sprintf ( "Unable to satisfy constraint '%s', no values for column(s): %s",
608 join (', ', map { "'$_'" } @missing),
615 =head2 search_related
619 =item Arguments: $rel, $cond, \%attrs?
621 =item Return Value: $new_resultset
625 $new_rs = $cd_rs->search_related('artist', {
629 Searches the specified relationship, optionally specifying a condition and
630 attributes for matching records. See L</ATTRIBUTES> for more information.
635 return shift->related_resultset(shift)->search(@_);
638 =head2 search_related_rs
640 This method works exactly the same as search_related, except that
641 it guarantees a resultset, even in list context.
645 sub search_related_rs {
646 return shift->related_resultset(shift)->search_rs(@_);
653 =item Arguments: none
655 =item Return Value: $cursor
659 Returns a storage-driven cursor to the given resultset. See
660 L<DBIx::Class::Cursor> for more information.
667 my $attrs = $self->_resolved_attrs_copy;
669 return $self->{cursor}
670 ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
671 $attrs->{where},$attrs);
678 =item Arguments: $cond?
680 =item Return Value: $row_object | undef
684 my $cd = $schema->resultset('CD')->single({ year => 2001 });
686 Inflates the first result without creating a cursor if the resultset has
687 any records in it; if not returns C<undef>. Used by L</find> as a lean version
690 While this method can take an optional search condition (just like L</search>)
691 being a fast-code-path it does not recognize search attributes. If you need to
692 add extra joins or similar, call L</search> and then chain-call L</single> on the
693 L<DBIx::Class::ResultSet> returned.
699 As of 0.08100, this method enforces the assumption that the preceding
700 query returns only one row. If more than one row is returned, you will receive
703 Query returned more than one row
705 In this case, you should be using L</next> or L</find> instead, or if you really
706 know what you are doing, use the L</rows> attribute to explicitly limit the size
709 This method will also throw an exception if it is called on a resultset prefetching
710 has_many, as such a prefetch implies fetching multiple rows from the database in
711 order to assemble the resulting object.
718 my ($self, $where) = @_;
720 $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
723 my $attrs = $self->_resolved_attrs_copy;
725 if (keys %{$attrs->{collapse}}) {
726 $self->throw_exception(
727 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
732 if (defined $attrs->{where}) {
735 [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
736 $where, delete $attrs->{where} ]
739 $attrs->{where} = $where;
743 my @data = $self->result_source->storage->select_single(
744 $attrs->{from}, $attrs->{select},
745 $attrs->{where}, $attrs
748 return (@data ? ($self->_construct_object(@data))[0] : undef);
754 # Recursively collapse the query, accumulating values for each column.
756 sub _collapse_query {
757 my ($self, $query, $collapsed) = @_;
761 if (ref $query eq 'ARRAY') {
762 foreach my $subquery (@$query) {
763 next unless ref $subquery; # -or
764 $collapsed = $self->_collapse_query($subquery, $collapsed);
767 elsif (ref $query eq 'HASH') {
768 if (keys %$query and (keys %$query)[0] eq '-and') {
769 foreach my $subquery (@{$query->{-and}}) {
770 $collapsed = $self->_collapse_query($subquery, $collapsed);
774 foreach my $col (keys %$query) {
775 my $value = $query->{$col};
776 $collapsed->{$col}{$value}++;
788 =item Arguments: $cond?
790 =item Return Value: $resultsetcolumn
794 my $max_length = $rs->get_column('length')->max;
796 Returns a L<DBIx::Class::ResultSetColumn> instance for a column of the ResultSet.
801 my ($self, $column) = @_;
802 my $new = DBIx::Class::ResultSetColumn->new($self, $column);
810 =item Arguments: $cond, \%attrs?
812 =item Return Value: $resultset (scalar context), @row_objs (list context)
816 # WHERE title LIKE '%blue%'
817 $cd_rs = $rs->search_like({ title => '%blue%'});
819 Performs a search, but uses C<LIKE> instead of C<=> as the condition. Note
820 that this is simply a convenience method retained for ex Class::DBI users.
821 You most likely want to use L</search> with specific operators.
823 For more information, see L<DBIx::Class::Manual::Cookbook>.
825 This method is deprecated and will be removed in 0.09. Use L</search()>
826 instead. An example conversion is:
828 ->search_like({ foo => 'bar' });
832 ->search({ foo => { like => 'bar' } });
839 'search_like() is deprecated and will be removed in DBIC version 0.09.'
840 .' Instead use ->search({ x => { -like => "y%" } })'
841 .' (note the outer pair of {}s - they are important!)'
843 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
844 my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
845 $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
846 return $class->search($query, { %$attrs });
853 =item Arguments: $first, $last
855 =item Return Value: $resultset (scalar context), @row_objs (list context)
859 Returns a resultset or object list representing a subset of elements from the
860 resultset slice is called on. Indexes are from 0, i.e., to get the first
863 my ($one, $two, $three) = $rs->slice(0, 2);
868 my ($self, $min, $max) = @_;
869 my $attrs = {}; # = { %{ $self->{attrs} || {} } };
870 $attrs->{offset} = $self->{attrs}{offset} || 0;
871 $attrs->{offset} += $min;
872 $attrs->{rows} = ($max ? ($max - $min + 1) : 1);
873 return $self->search(undef, $attrs);
874 #my $slice = (ref $self)->new($self->result_source, $attrs);
875 #return (wantarray ? $slice->all : $slice);
882 =item Arguments: none
884 =item Return Value: $result | undef
888 Returns the next element in the resultset (C<undef> is there is none).
890 Can be used to efficiently iterate over records in the resultset:
892 my $rs = $schema->resultset('CD')->search;
893 while (my $cd = $rs->next) {
897 Note that you need to store the resultset object, and call C<next> on it.
898 Calling C<< resultset('Table')->next >> repeatedly will always return the
899 first record from the resultset.
905 if (my $cache = $self->get_cache) {
906 $self->{all_cache_position} ||= 0;
907 return $cache->[$self->{all_cache_position}++];
909 if ($self->{attrs}{cache}) {
910 delete $self->{pager};
911 $self->{all_cache_position} = 1;
912 return ($self->all)[0];
914 if ($self->{stashed_objects}) {
915 my $obj = shift(@{$self->{stashed_objects}});
916 delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
920 exists $self->{stashed_row}
921 ? @{delete $self->{stashed_row}}
922 : $self->cursor->next
924 return undef unless (@row);
925 my ($row, @more) = $self->_construct_object(@row);
926 $self->{stashed_objects} = \@more if @more;
930 sub _construct_object {
931 my ($self, @row) = @_;
933 my $info = $self->_collapse_result($self->{_attrs}{as}, \@row)
935 my @new = $self->result_class->inflate_result($self->result_source, @$info);
936 @new = $self->{_attrs}{record_filter}->(@new)
937 if exists $self->{_attrs}{record_filter};
941 sub _collapse_result {
942 my ($self, $as_proto, $row) = @_;
946 # 'foo' => [ undef, 'foo' ]
947 # 'foo.bar' => [ 'foo', 'bar' ]
948 # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
950 my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
952 my %collapse = %{$self->{_attrs}{collapse}||{}};
956 # if we're doing collapsing (has_many prefetch) we need to grab records
957 # until the PK changes, so fill @pri_index. if not, we leave it empty so
958 # we know we don't have to bother.
960 # the reason for not using the collapse stuff directly is because if you
961 # had for e.g. two artists in a row with no cds, the collapse info for
962 # both would be NULL (undef) so you'd lose the second artist
964 # store just the index so we can check the array positions from the row
965 # without having to contruct the full hash
967 if (keys %collapse) {
968 my %pri = map { ($_ => 1) } $self->result_source->_pri_cols;
969 foreach my $i (0 .. $#construct_as) {
970 next if defined($construct_as[$i][0]); # only self table
971 if (delete $pri{$construct_as[$i][1]}) {
972 push(@pri_index, $i);
974 last unless keys %pri; # short circuit (Johnny Five Is Alive!)
978 # no need to do an if, it'll be empty if @pri_index is empty anyway
980 my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
984 do { # no need to check anything at the front, we always want the first row
988 foreach my $this_as (@construct_as) {
989 $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
992 push(@const_rows, \%const);
994 } until ( # no pri_index => no collapse => drop straight out
997 do { # get another row, stash it, drop out if different PK
999 @copy = $self->cursor->next;
1000 $self->{stashed_row} = \@copy;
1002 # last thing in do block, counts as true if anything doesn't match
1004 # check xor defined first for NULL vs. NOT NULL then if one is
1005 # defined the other must be so check string equality
1008 (defined $pri_vals{$_} ^ defined $copy[$_])
1009 || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
1014 my $alias = $self->{attrs}{alias};
1021 foreach my $const (@const_rows) {
1022 scalar @const_keys or do {
1023 @const_keys = sort { length($a) <=> length($b) } keys %$const;
1025 foreach my $key (@const_keys) {
1028 my @parts = split(/\./, $key);
1030 my $data = $const->{$key};
1031 foreach my $p (@parts) {
1032 $target = $target->[1]->{$p} ||= [];
1034 if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
1035 # collapsing at this point and on final part
1036 my $pos = $collapse_pos{$cur};
1037 CK: foreach my $ck (@ckey) {
1038 if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
1039 $collapse_pos{$cur} = $data;
1040 delete @collapse_pos{ # clear all positioning for sub-entries
1041 grep { m/^\Q${cur}.\E/ } keys %collapse_pos
1048 if (exists $collapse{$cur}) {
1049 $target = $target->[-1];
1052 $target->[0] = $data;
1054 $info->[0] = $const->{$key};
1062 =head2 result_source
1066 =item Arguments: $result_source?
1068 =item Return Value: $result_source
1072 An accessor for the primary ResultSource object from which this ResultSet
1079 =item Arguments: $result_class?
1081 =item Return Value: $result_class
1085 An accessor for the class to use when creating row objects. Defaults to
1086 C<< result_source->result_class >> - which in most cases is the name of the
1087 L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class.
1089 Note that changing the result_class will also remove any components
1090 that were originally loaded in the source class via
1091 L<DBIx::Class::ResultSource/load_components>. Any overloaded methods
1092 in the original source class will not run.
1097 my ($self, $result_class) = @_;
1098 if ($result_class) {
1099 unless (ref $result_class) { # don't fire this for an object
1100 $self->ensure_class_loaded($result_class);
1102 $self->_result_class($result_class);
1103 # THIS LINE WOULD BE A BUG - this accessor specifically exists to
1104 # permit the user to set result class on one result set only; it only
1105 # chains if provided to search()
1106 #$self->{attrs}{result_class} = $result_class if ref $self;
1108 $self->_result_class;
1115 =item Arguments: $cond, \%attrs??
1117 =item Return Value: $count
1121 Performs an SQL C<COUNT> with the same query as the resultset was built
1122 with to find the number of elements. Passing arguments is equivalent to
1123 C<< $rs->search ($cond, \%attrs)->count >>
1129 return $self->search(@_)->count if @_ and defined $_[0];
1130 return scalar @{ $self->get_cache } if $self->get_cache;
1132 my $attrs = $self->_resolved_attrs_copy;
1134 # this is a little optimization - it is faster to do the limit
1135 # adjustments in software, instead of a subquery
1136 my $rows = delete $attrs->{rows};
1137 my $offset = delete $attrs->{offset};
1140 if ($self->_has_resolved_attr (qw/collapse group_by/)) {
1141 $crs = $self->_count_subq_rs ($attrs);
1144 $crs = $self->_count_rs ($attrs);
1146 my $count = $crs->next;
1148 $count -= $offset if $offset;
1149 $count = $rows if $rows and $rows < $count;
1150 $count = 0 if ($count < 0);
1159 =item Arguments: $cond, \%attrs??
1161 =item Return Value: $count_rs
1165 Same as L</count> but returns a L<DBIx::Class::ResultSetColumn> object.
1166 This can be very handy for subqueries:
1168 ->search( { amount => $some_rs->count_rs->as_query } )
1170 As with regular resultsets the SQL query will be executed only after
1171 the resultset is accessed via L</next> or L</all>. That would return
1172 the same single value obtainable via L</count>.
1178 return $self->search(@_)->count_rs if @_;
1180 # this may look like a lack of abstraction (count() does about the same)
1181 # but in fact an _rs *must* use a subquery for the limits, as the
1182 # software based limiting can not be ported if this $rs is to be used
1183 # in a subquery itself (i.e. ->as_query)
1184 if ($self->_has_resolved_attr (qw/collapse group_by offset rows/)) {
1185 return $self->_count_subq_rs;
1188 return $self->_count_rs;
1193 # returns a ResultSetColumn object tied to the count query
1196 my ($self, $attrs) = @_;
1198 my $rsrc = $self->result_source;
1199 $attrs ||= $self->_resolved_attrs;
1201 my $tmp_attrs = { %$attrs };
1202 # take off any limits, record_filter is cdbi, and no point of ordering nor locking a count
1203 delete @{$tmp_attrs}{qw/rows offset order_by record_filter for/};
1205 # overwrite the selector (supplied by the storage)
1206 $tmp_attrs->{select} = $rsrc->storage->_count_select ($rsrc, $attrs);
1207 $tmp_attrs->{as} = 'count';
1209 my $tmp_rs = $rsrc->resultset_class->new($rsrc, $tmp_attrs)->get_column ('count');
1215 # same as above but uses a subquery
1217 sub _count_subq_rs {
1218 my ($self, $attrs) = @_;
1220 my $rsrc = $self->result_source;
1221 $attrs ||= $self->_resolved_attrs;
1223 my $sub_attrs = { %$attrs };
1224 # extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
1225 delete @{$sub_attrs}{qw/collapse select _prefetch_select as order_by for/};
1227 # if we multi-prefetch we group_by primary keys only as this is what we would
1228 # get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
1229 if ( keys %{$attrs->{collapse}} ) {
1230 $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } ($rsrc->_pri_cols) ]
1233 # Calculate subquery selector
1234 if (my $g = $sub_attrs->{group_by}) {
1236 my $sql_maker = $rsrc->storage->sql_maker;
1238 # necessary as the group_by may refer to aliased functions
1240 for my $sel (@{$attrs->{select}}) {
1241 $sel_index->{$sel->{-as}} = $sel
1242 if (ref $sel eq 'HASH' and $sel->{-as});
1245 for my $g_part (@$g) {
1246 my $colpiece = $sel_index->{$g_part} || $g_part;
1248 # disqualify join-based group_by's. Arcane but possible query
1249 # also horrible horrible hack to alias a column (not a func.)
1250 # (probably need to introduce SQLA syntax)
1251 if ($colpiece =~ /\./ && $colpiece !~ /^$attrs->{alias}\./) {
1254 $colpiece = \ sprintf ('%s AS %s', map { $sql_maker->_quote ($_) } ($colpiece, $as) );
1256 push @{$sub_attrs->{select}}, $colpiece;
1260 my @pcols = map { "$attrs->{alias}.$_" } ($rsrc->primary_columns);
1261 $sub_attrs->{select} = @pcols ? \@pcols : [ 1 ];
1264 return $rsrc->resultset_class
1265 ->new ($rsrc, $sub_attrs)
1267 ->search ({}, { columns => { count => $rsrc->storage->_count_select ($rsrc, $attrs) } })
1268 ->get_column ('count');
1275 =head2 count_literal
1279 =item Arguments: $sql_fragment, @bind_values
1281 =item Return Value: $count
1285 Counts the results in a literal query. Equivalent to calling L</search_literal>
1286 with the passed arguments, then L</count>.
1290 sub count_literal { shift->search_literal(@_)->count; }
1296 =item Arguments: none
1298 =item Return Value: @objects
1302 Returns all elements in the resultset. Called implicitly if the resultset
1303 is returned in list context.
1310 $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
1313 return @{ $self->get_cache } if $self->get_cache;
1317 if (keys %{$self->_resolved_attrs->{collapse}}) {
1318 # Using $self->cursor->all is really just an optimisation.
1319 # If we're collapsing has_many prefetches it probably makes
1320 # very little difference, and this is cleaner than hacking
1321 # _construct_object to survive the approach
1322 $self->cursor->reset;
1323 my @row = $self->cursor->next;
1325 push(@obj, $self->_construct_object(@row));
1326 @row = (exists $self->{stashed_row}
1327 ? @{delete $self->{stashed_row}}
1328 : $self->cursor->next);
1331 @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
1334 $self->set_cache(\@obj) if $self->{attrs}{cache};
1343 =item Arguments: none
1345 =item Return Value: $self
1349 Resets the resultset's cursor, so you can iterate through the elements again.
1350 Implicitly resets the storage cursor, so a subsequent L</next> will trigger
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 | undef
1373 Resets the resultset and returns an object for the first result (or C<undef>
1374 if the resultset is empty).
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 # if a condition exists we need to strip all table qualifiers
1395 # if this is not possible we'll force a subquery below
1396 my $cond = $rsrc->schema->storage->_strip_cond_qualifiers ($self->{cond});
1398 my $needs_group_by_subq = $self->_has_resolved_attr (qw/collapse group_by -join/);
1399 my $needs_subq = $needs_group_by_subq || (not defined $cond) || $self->_has_resolved_attr(qw/rows offset/);
1401 if ($needs_group_by_subq or $needs_subq) {
1403 # make a new $rs selecting only the PKs (that's all we really need)
1404 my $attrs = $self->_resolved_attrs_copy;
1407 delete $attrs->{$_} for qw/collapse _collapse_order_by select _prefetch_select as/;
1408 $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->_pri_cols) ];
1410 if ($needs_group_by_subq) {
1411 # make sure no group_by was supplied, or if there is one - make sure it matches
1412 # the columns compiled above perfectly. Anything else can not be sanely executed
1413 # on most databases so croak right then and there
1415 if (my $g = $attrs->{group_by}) {
1416 my @current_group_by = map
1417 { $_ =~ /\./ ? $_ : "$attrs->{alias}.$_" }
1422 join ("\x00", sort @current_group_by)
1424 join ("\x00", sort @{$attrs->{columns}} )
1426 $self->throw_exception (
1427 "You have just attempted a $op operation on a resultset which does group_by"
1428 . ' on columns other than the primary keys, while DBIC internally needs to retrieve'
1429 . ' the primary keys in a subselect. All sane RDBMS engines do not support this'
1430 . ' kind of queries. Please retry the operation with a modified group_by or'
1431 . ' without using one at all.'
1436 $attrs->{group_by} = $attrs->{columns};
1440 my $subrs = (ref $self)->new($rsrc, $attrs);
1441 return $self->result_source->storage->_subq_update_delete($subrs, $op, $values);
1444 return $rsrc->storage->$op(
1446 $op eq 'update' ? $values : (),
1456 =item Arguments: \%values
1458 =item Return Value: $storage_rv
1462 Sets the specified columns in the resultset to the supplied values in a
1463 single query. Note that this will not run any accessor/set_column/update
1464 triggers, nor will it update any row object instances derived from this
1465 resultset (this includes the contents of the L<resultset cache|/set_cache>
1466 if any). See L</update_all> if you need to execute any on-update
1467 triggers or cascades defined either by you or a
1468 L<result component|DBIx::Class::Manual::Component/WHAT_IS_A_COMPONENT>.
1470 The return value is a pass through of what the underlying
1471 storage backend returned, and may vary. See L<DBI/execute> for the most
1477 my ($self, $values) = @_;
1478 $self->throw_exception('Values for update must be a hash')
1479 unless ref $values eq 'HASH';
1481 return $self->_rs_update_delete ('update', $values);
1488 =item Arguments: \%values
1490 =item Return Value: 1
1494 Fetches all objects and updates them one at a time via
1495 L<DBIx::Class::Row/update>. Note that C<update_all> will run DBIC defined
1496 triggers, while L</update> will not.
1501 my ($self, $values) = @_;
1502 $self->throw_exception('Values for update_all must be a hash')
1503 unless ref $values eq 'HASH';
1505 my $guard = $self->result_source->schema->txn_scope_guard;
1506 $_->update($values) for $self->all;
1515 =item Arguments: none
1517 =item Return Value: $storage_rv
1521 Deletes the rows matching this resultset in a single query. Note that this
1522 will not run any delete triggers, nor will it alter the
1523 L<in_storage|DBIx::Class::Row/in_storage> status of any row object instances
1524 derived from this resultset (this includes the contents of the
1525 L<resultset cache|/set_cache> if any). See L</delete_all> if you need to
1526 execute any on-delete triggers or cascades defined either by you or a
1527 L<result component|DBIx::Class::Manual::Component/WHAT_IS_A_COMPONENT>.
1529 The return value is a pass through of what the underlying storage backend
1530 returned, and may vary. See L<DBI/execute> for the most common case.
1536 $self->throw_exception('delete does not accept any arguments')
1539 return $self->_rs_update_delete ('delete');
1546 =item Arguments: none
1548 =item Return Value: 1
1552 Fetches all objects and deletes them one at a time via
1553 L<DBIx::Class::Row/delete>. Note that C<delete_all> will run DBIC defined
1554 triggers, while L</delete> will not.
1560 $self->throw_exception('delete_all does not accept any arguments')
1563 my $guard = $self->result_source->schema->txn_scope_guard;
1564 $_->delete for $self->all;
1573 =item Arguments: \@data;
1577 Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs.
1578 For the arrayref of hashrefs style each hashref should be a structure suitable
1579 forsubmitting to a $resultset->create(...) method.
1581 In void context, C<insert_bulk> in L<DBIx::Class::Storage::DBI> is used
1582 to insert the data, as this is a faster method.
1584 Otherwise, each set of data is inserted into the database using
1585 L<DBIx::Class::ResultSet/create>, and the resulting objects are
1586 accumulated into an array. The array itself, or an array reference
1587 is returned depending on scalar or list context.
1589 Example: Assuming an Artist Class that has many CDs Classes relating:
1591 my $Artist_rs = $schema->resultset("Artist");
1593 ## Void Context Example
1594 $Artist_rs->populate([
1595 { artistid => 4, name => 'Manufactured Crap', cds => [
1596 { title => 'My First CD', year => 2006 },
1597 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
1600 { artistid => 5, name => 'Angsty-Whiny Girl', cds => [
1601 { title => 'My parents sold me to a record company', year => 2005 },
1602 { title => 'Why Am I So Ugly?', year => 2006 },
1603 { title => 'I Got Surgery and am now Popular', year => 2007 }
1608 ## Array Context Example
1609 my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([
1610 { name => "Artist One"},
1611 { name => "Artist Two"},
1612 { name => "Artist Three", cds=> [
1613 { title => "First CD", year => 2007},
1614 { title => "Second CD", year => 2008},
1618 print $ArtistOne->name; ## response is 'Artist One'
1619 print $ArtistThree->cds->count ## reponse is '2'
1621 For the arrayref of arrayrefs style, the first element should be a list of the
1622 fieldsnames to which the remaining elements are rows being inserted. For
1625 $Arstist_rs->populate([
1626 [qw/artistid name/],
1627 [100, 'A Formally Unknown Singer'],
1628 [101, 'A singer that jumped the shark two albums ago'],
1629 [102, 'An actually cool singer'],
1632 Please note an important effect on your data when choosing between void and
1633 wantarray context. Since void context goes straight to C<insert_bulk> in
1634 L<DBIx::Class::Storage::DBI> this will skip any component that is overriding
1635 C<insert>. So if you are using something like L<DBIx-Class-UUIDColumns> to
1636 create primary keys for you, you will find that your PKs are empty. In this
1637 case you will have to use the wantarray context in order to create those
1645 # cruft placed in standalone method
1646 my $data = $self->_normalize_populate_args(@_);
1648 if(defined wantarray) {
1650 foreach my $item (@$data) {
1651 push(@created, $self->create($item));
1653 return wantarray ? @created : \@created;
1655 my $first = $data->[0];
1657 # if a column is a registered relationship, and is a non-blessed hash/array, consider
1658 # it relationship data
1659 my (@rels, @columns);
1660 for (keys %$first) {
1661 my $ref = ref $first->{$_};
1662 $self->result_source->has_relationship($_) && ($ref eq 'ARRAY' or $ref eq 'HASH')
1668 my @pks = $self->result_source->primary_columns;
1670 ## do the belongs_to relationships
1671 foreach my $index (0..$#$data) {
1673 # delegate to create() for any dataset without primary keys with specified relationships
1674 if (grep { !defined $data->[$index]->{$_} } @pks ) {
1676 if (grep { ref $data->[$index]{$r} eq $_ } qw/HASH ARRAY/) { # a related set must be a HASH or AoH
1677 my @ret = $self->populate($data);
1683 foreach my $rel (@rels) {
1684 next unless ref $data->[$index]->{$rel} eq "HASH";
1685 my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel});
1686 my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)};
1687 my $related = $result->result_source->_resolve_condition(
1688 $result->result_source->relationship_info($reverse)->{cond},
1693 delete $data->[$index]->{$rel};
1694 $data->[$index] = {%{$data->[$index]}, %$related};
1696 push @columns, keys %$related if $index == 0;
1700 ## inherit the data locked in the conditions of the resultset
1701 my ($rs_data) = $self->_merge_with_rscond({});
1702 delete @{$rs_data}{@columns};
1703 my @inherit_cols = keys %$rs_data;
1704 my @inherit_data = values %$rs_data;
1706 ## do bulk insert on current row
1707 $self->result_source->storage->insert_bulk(
1708 $self->result_source,
1709 [@columns, @inherit_cols],
1710 [ map { [ @$_{@columns}, @inherit_data ] } @$data ],
1713 ## do the has_many relationships
1714 foreach my $item (@$data) {
1716 foreach my $rel (@rels) {
1717 next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY";
1719 my $parent = $self->find({map { $_ => $item->{$_} } @pks})
1720 || $self->throw_exception('Cannot find the relating object.');
1722 my $child = $parent->$rel;
1724 my $related = $child->result_source->_resolve_condition(
1725 $parent->result_source->relationship_info($rel)->{cond},
1730 my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel});
1731 my @populate = map { {%$_, %$related} } @rows_to_add;
1733 $child->populate( \@populate );
1740 # populate() argumnets went over several incarnations
1741 # What we ultimately support is AoH
1742 sub _normalize_populate_args {
1743 my ($self, $arg) = @_;
1745 if (ref $arg eq 'ARRAY') {
1746 if (ref $arg->[0] eq 'HASH') {
1749 elsif (ref $arg->[0] eq 'ARRAY') {
1751 my @colnames = @{$arg->[0]};
1752 foreach my $values (@{$arg}[1 .. $#$arg]) {
1753 push @ret, { map { $colnames[$_] => $values->[$_] } (0 .. $#colnames) };
1759 $self->throw_exception('Populate expects an arrayref of hashrefs or arrayref of arrayrefs');
1766 =item Arguments: none
1768 =item Return Value: $pager
1772 Return Value a L<Data::Page> object for the current resultset. Only makes
1773 sense for queries with a C<page> attribute.
1775 To get the full count of entries for a paged resultset, call
1776 C<total_entries> on the L<Data::Page> object.
1780 # make a wizard good for both a scalar and a hashref
1781 my $mk_lazy_count_wizard = sub {
1782 require Variable::Magic;
1784 my $stash = { total_rs => shift };
1785 my $slot = shift; # only used by the hashref magic
1787 my $magic = Variable::Magic::wizard (
1788 data => sub { $stash },
1794 # set value lazily, and dispell for good
1795 ${$_[0]} = $_[1]{total_rs}->count;
1796 Variable::Magic::dispell (${$_[0]}, $_[1]{magic_selfref});
1800 # an explicit set implies dispell as well
1801 # the unless() is to work around "fun and giggles" below
1802 Variable::Magic::dispell (${$_[0]}, $_[1]{magic_selfref})
1803 unless (caller(2))[3] eq 'DBIx::Class::ResultSet::pager';
1810 if ($_[2] eq $slot and !$_[1]{inactive}) {
1811 my $cnt = $_[1]{total_rs}->count;
1812 $_[0]->{$slot} = $cnt;
1814 # attempting to dispell in a fetch handle (works in store), seems
1815 # to invariable segfault on 5.10, 5.12, 5.13 :(
1816 # so use an inactivator instead
1817 #Variable::Magic::dispell (%{$_[0]}, $_[1]{magic_selfref});
1823 if (! $_[1]{inactive} and $_[2] eq $slot) {
1824 #Variable::Magic::dispell (%{$_[0]}, $_[1]{magic_selfref});
1826 unless (caller(2))[3] eq 'DBIx::Class::ResultSet::pager';
1833 $stash->{magic_selfref} = $magic;
1834 weaken ($stash->{magic_selfref}); # this fails on 5.8.1
1839 # the tie class for 5.8.1
1841 package DBIx::Class::__DBIC_LAZY_RS_COUNT__;
1842 use base qw/Tie::Hash/;
1844 sub FIRSTKEY { my $dummy = scalar keys %{$_[0]{data}}; each %{$_[0]{data}} }
1845 sub NEXTKEY { each %{$_[0]{data}} }
1846 sub EXISTS { exists $_[0]{data}{$_[1]} }
1847 sub DELETE { delete $_[0]{data}{$_[1]} }
1848 sub CLEAR { %{$_[0]{data}} = () }
1849 sub SCALAR { scalar %{$_[0]{data}} }
1852 $_[1]{data} = {%{$_[1]{selfref}}};
1853 %{$_[1]{selfref}} = ();
1854 Scalar::Util::weaken ($_[1]{selfref});
1855 return bless ($_[1], $_[0]);
1859 if ($_[1] eq $_[0]{slot}) {
1860 my $cnt = $_[0]{data}{$_[1]} = $_[0]{total_rs}->count;
1861 untie %{$_[0]{selfref}};
1862 %{$_[0]{selfref}} = %{$_[0]{data}};
1871 $_[0]{data}{$_[1]} = $_[2];
1872 if ($_[1] eq $_[0]{slot}) {
1873 untie %{$_[0]{selfref}};
1874 %{$_[0]{selfref}} = %{$_[0]{data}};
1883 return $self->{pager} if $self->{pager};
1885 if ($self->get_cache) {
1886 $self->throw_exception ('Pagers on cached resultsets are not supported');
1889 my $attrs = $self->{attrs};
1890 $self->throw_exception("Can't create pager for non-paged rs")
1891 unless $self->{attrs}{page};
1892 $attrs->{rows} ||= 10;
1894 # throw away the paging flags and re-run the count (possibly
1895 # with a subselect) to get the real total count
1896 my $count_attrs = { %$attrs };
1897 delete $count_attrs->{$_} for qw/rows offset page pager/;
1898 my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
1901 ### the following may seem awkward and dirty, but it's a thought-experiment
1902 ### necessary for future development of DBIx::DS. Do *NOT* change this code
1903 ### before talking to ribasushi/mst
1905 my $pager = Data::Page->new(
1906 0, #start with an empty set
1908 $self->{attrs}{page},
1911 my $data_slot = 'total_entries';
1913 # Since we are interested in a cached value (once it's set - it's set), every
1914 # technique will detach from the magic-host once the time comes to fire the
1915 # ->count (or in the segfaulting case of >= 5.10 it will deactivate itself)
1917 if ($] < 5.008003) {
1918 # 5.8.1 throws 'Modification of a read-only value attempted' when one tries
1919 # to weakref the magic container :(
1921 tie (%$pager, 'DBIx::Class::__DBIC_LAZY_RS_COUNT__',
1922 { slot => $data_slot, total_rs => $total_rs, selfref => $pager }
1925 elsif ($] < 5.010) {
1926 # We can use magic on the hash value slot. It's interesting that the magic is
1927 # attached to the hash-slot, and does *not* stop working once I do the dummy
1928 # assignments after the cast()
1929 # tested on 5.8.3 and 5.8.9
1930 my $magic = $mk_lazy_count_wizard->($total_rs);
1931 Variable::Magic::cast ( $pager->{$data_slot}, $magic );
1933 # this is for fun and giggles
1934 $pager->{$data_slot} = -1;
1935 $pager->{$data_slot} = 0;
1937 # this does not work for scalars, but works with
1939 #my %vals = %$pager;
1944 # And the uvar magic
1945 # works on 5.10.1, 5.12.1 and 5.13.4 in its current form,
1946 # however see the wizard maker for more notes
1947 my $magic = $mk_lazy_count_wizard->($total_rs, $data_slot);
1948 Variable::Magic::cast ( %$pager, $magic );
1951 $pager->{$data_slot} = -1;
1952 $pager->{$data_slot} = 0;
1960 return $self->{pager} = $pager;
1967 =item Arguments: $page_number
1969 =item Return Value: $rs
1973 Returns a resultset for the $page_number page of the resultset on which page
1974 is called, where each page contains a number of rows equal to the 'rows'
1975 attribute set on the resultset (10 by default).
1980 my ($self, $page) = @_;
1981 return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page });
1988 =item Arguments: \%vals
1990 =item Return Value: $rowobject
1994 Creates a new row object in the resultset's result class and returns
1995 it. The row is not inserted into the database at this point, call
1996 L<DBIx::Class::Row/insert> to do that. Calling L<DBIx::Class::Row/in_storage>
1997 will tell you whether the row object has been inserted or not.
1999 Passes the hashref of input on to L<DBIx::Class::Row/new>.
2004 my ($self, $values) = @_;
2005 $self->throw_exception( "new_result needs a hash" )
2006 unless (ref $values eq 'HASH');
2008 my ($merged_cond, $cols_from_relations) = $self->_merge_with_rscond($values);
2012 @$cols_from_relations
2013 ? (-cols_from_relations => $cols_from_relations)
2015 -source_handle => $self->_source_handle,
2016 -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED
2019 return $self->result_class->new(\%new);
2022 # _merge_with_rscond
2024 # Takes a simple hash of K/V data and returns its copy merged with the
2025 # condition already present on the resultset. Additionally returns an
2026 # arrayref of value/condition names, which were inferred from related
2027 # objects (this is needed for in-memory related objects)
2028 sub _merge_with_rscond {
2029 my ($self, $data) = @_;
2031 my (%new_data, @cols_from_relations);
2033 my $alias = $self->{attrs}{alias};
2035 if (! defined $self->{cond}) {
2036 # just massage $data below
2038 elsif ($self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
2039 %new_data = %{ $self->{attrs}{related_objects} || {} }; # nothing might have been inserted yet
2040 @cols_from_relations = keys %new_data;
2042 elsif (ref $self->{cond} ne 'HASH') {
2043 $self->throw_exception(
2044 "Can't abstract implicit construct, resultset condition not a hash"
2048 # precendence must be given to passed values over values inherited from
2049 # the cond, so the order here is important.
2050 my $collapsed_cond = $self->_collapse_cond($self->{cond});
2051 my %implied = %{$self->_remove_alias($collapsed_cond, $alias)};
2053 while ( my($col, $value) = each %implied ) {
2054 my $vref = ref $value;
2055 if ($vref eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '=') {
2056 $new_data{$col} = $value->{'='};
2058 elsif( !$vref or $vref eq 'SCALAR' or blessed($value) ) {
2059 $new_data{$col} = $value;
2066 %{ $self->_remove_alias($data, $alias) },
2069 return (\%new_data, \@cols_from_relations);
2072 # _has_resolved_attr
2074 # determines if the resultset defines at least one
2075 # of the attributes supplied
2077 # used to determine if a subquery is neccessary
2079 # supports some virtual attributes:
2081 # This will scan for any joins being present on the resultset.
2082 # It is not a mere key-search but a deep inspection of {from}
2085 sub _has_resolved_attr {
2086 my ($self, @attr_names) = @_;
2088 my $attrs = $self->_resolved_attrs;
2092 for my $n (@attr_names) {
2093 if (grep { $n eq $_ } (qw/-join/) ) {
2094 $extra_checks{$n}++;
2098 my $attr = $attrs->{$n};
2100 next if not defined $attr;
2102 if (ref $attr eq 'HASH') {
2103 return 1 if keys %$attr;
2105 elsif (ref $attr eq 'ARRAY') {
2113 # a resolved join is expressed as a multi-level from
2115 $extra_checks{-join}
2117 ref $attrs->{from} eq 'ARRAY'
2119 @{$attrs->{from}} > 1
2127 # Recursively collapse the condition.
2129 sub _collapse_cond {
2130 my ($self, $cond, $collapsed) = @_;
2134 if (ref $cond eq 'ARRAY') {
2135 foreach my $subcond (@$cond) {
2136 next unless ref $subcond; # -or
2137 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2140 elsif (ref $cond eq 'HASH') {
2141 if (keys %$cond and (keys %$cond)[0] eq '-and') {
2142 foreach my $subcond (@{$cond->{-and}}) {
2143 $collapsed = $self->_collapse_cond($subcond, $collapsed);
2147 foreach my $col (keys %$cond) {
2148 my $value = $cond->{$col};
2149 $collapsed->{$col} = $value;
2159 # Remove the specified alias from the specified query hash. A copy is made so
2160 # the original query is not modified.
2163 my ($self, $query, $alias) = @_;
2165 my %orig = %{ $query || {} };
2168 foreach my $key (keys %orig) {
2170 $unaliased{$key} = $orig{$key};
2173 $unaliased{$1} = $orig{$key}
2174 if $key =~ m/^(?:\Q$alias\E\.)?([^.]+)$/;
2184 =item Arguments: none
2186 =item Return Value: \[ $sql, @bind ]
2190 Returns the SQL query and bind vars associated with the invocant.
2192 This is generally used as the RHS for a subquery.
2199 my $attrs = $self->_resolved_attrs_copy;
2204 # my ($sql, \@bind, \%dbi_bind_attrs) = _select_args_to_query (...)
2205 # $sql also has no wrapping parenthesis in list ctx
2207 my $sqlbind = $self->result_source->storage
2208 ->_select_args_to_query ($attrs->{from}, $attrs->{select}, $attrs->{where}, $attrs);
2217 =item Arguments: \%vals, \%attrs?
2219 =item Return Value: $rowobject
2223 my $artist = $schema->resultset('Artist')->find_or_new(
2224 { artist => 'fred' }, { key => 'artists' });
2226 $cd->cd_to_producer->find_or_new({ producer => $producer },
2227 { key => 'primary });
2229 Find an existing record from this resultset using L</find>. if none exists,
2230 instantiate a new result object and return it. The object will not be saved
2231 into your storage until you call L<DBIx::Class::Row/insert> on it.
2233 You most likely want this method when looking for existing rows using a unique
2234 constraint that is not the primary key, or looking for related rows.
2236 If you want objects to be saved immediately, use L</find_or_create> instead.
2238 B<Note>: Make sure to read the documentation of L</find> and understand the
2239 significance of the C<key> attribute, as its lack may skew your search, and
2240 subsequently result in spurious new objects.
2242 B<Note>: Take care when using C<find_or_new> with a table having
2243 columns with default values that you intend to be automatically
2244 supplied by the database (e.g. an auto_increment primary key column).
2245 In normal usage, the value of such columns should NOT be included at
2246 all in the call to C<find_or_new>, even when set to C<undef>.
2252 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2253 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2254 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2257 return $self->new_result($hash);
2264 =item Arguments: \%vals
2266 =item Return Value: a L<DBIx::Class::Row> $object
2270 Attempt to create a single new row or a row with multiple related rows
2271 in the table represented by the resultset (and related tables). This
2272 will not check for duplicate rows before inserting, use
2273 L</find_or_create> to do that.
2275 To create one row for this resultset, pass a hashref of key/value
2276 pairs representing the columns of the table and the values you wish to
2277 store. If the appropriate relationships are set up, foreign key fields
2278 can also be passed an object representing the foreign row, and the
2279 value will be set to its primary key.
2281 To create related objects, pass a hashref of related-object column values
2282 B<keyed on the relationship name>. If the relationship is of type C<multi>
2283 (L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
2284 The process will correctly identify columns holding foreign keys, and will
2285 transparently populate them from the keys of the corresponding relation.
2286 This can be applied recursively, and will work correctly for a structure
2287 with an arbitrary depth and width, as long as the relationships actually
2288 exists and the correct column data has been supplied.
2291 Instead of hashrefs of plain related data (key/value pairs), you may
2292 also pass new or inserted objects. New objects (not inserted yet, see
2293 L</new>), will be inserted into their appropriate tables.
2295 Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
2297 Example of creating a new row.
2299 $person_rs->create({
2300 name=>"Some Person",
2301 email=>"somebody@someplace.com"
2304 Example of creating a new row and also creating rows in a related C<has_many>
2305 or C<has_one> resultset. Note Arrayref.
2308 { artistid => 4, name => 'Manufactured Crap', cds => [
2309 { title => 'My First CD', year => 2006 },
2310 { title => 'Yet More Tweeny-Pop crap', year => 2007 },
2315 Example of creating a new row and also creating a row in a related
2316 C<belongs_to> resultset. Note Hashref.
2319 title=>"Music for Silly Walks",
2322 name=>"Silly Musician",
2330 When subclassing ResultSet never attempt to override this method. Since
2331 it is a simple shortcut for C<< $self->new_result($attrs)->insert >>, a
2332 lot of the internals simply never call it, so your override will be
2333 bypassed more often than not. Override either L<new|DBIx::Class::Row/new>
2334 or L<insert|DBIx::Class::Row/insert> depending on how early in the
2335 L</create> process you need to intervene.
2342 my ($self, $attrs) = @_;
2343 $self->throw_exception( "create needs a hashref" )
2344 unless ref $attrs eq 'HASH';
2345 return $self->new_result($attrs)->insert;
2348 =head2 find_or_create
2352 =item Arguments: \%vals, \%attrs?
2354 =item Return Value: $rowobject
2358 $cd->cd_to_producer->find_or_create({ producer => $producer },
2359 { key => 'primary' });
2361 Tries to find a record based on its primary key or unique constraints; if none
2362 is found, creates one and returns that instead.
2364 my $cd = $schema->resultset('CD')->find_or_create({
2366 artist => 'Massive Attack',
2367 title => 'Mezzanine',
2371 Also takes an optional C<key> attribute, to search by a specific key or unique
2372 constraint. For example:
2374 my $cd = $schema->resultset('CD')->find_or_create(
2376 artist => 'Massive Attack',
2377 title => 'Mezzanine',
2379 { key => 'cd_artist_title' }
2382 B<Note>: Make sure to read the documentation of L</find> and understand the
2383 significance of the C<key> attribute, as its lack may skew your search, and
2384 subsequently result in spurious row creation.
2386 B<Note>: Because find_or_create() reads from the database and then
2387 possibly inserts based on the result, this method is subject to a race
2388 condition. Another process could create a record in the table after
2389 the find has completed and before the create has started. To avoid
2390 this problem, use find_or_create() inside a transaction.
2392 B<Note>: Take care when using C<find_or_create> with a table having
2393 columns with default values that you intend to be automatically
2394 supplied by the database (e.g. an auto_increment primary key column).
2395 In normal usage, the value of such columns should NOT be included at
2396 all in the call to C<find_or_create>, even when set to C<undef>.
2398 See also L</find> and L</update_or_create>. For information on how to declare
2399 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2403 sub find_or_create {
2405 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2406 my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
2407 if (keys %$hash and my $row = $self->find($hash, $attrs) ) {
2410 return $self->create($hash);
2413 =head2 update_or_create
2417 =item Arguments: \%col_values, { key => $unique_constraint }?
2419 =item Return Value: $row_object
2423 $resultset->update_or_create({ col => $val, ... });
2425 Like L</find_or_create>, but if a row is found it is immediately updated via
2426 C<< $found_row->update (\%col_values) >>.
2429 Takes an optional C<key> attribute to search on a specific unique constraint.
2432 # In your application
2433 my $cd = $schema->resultset('CD')->update_or_create(
2435 artist => 'Massive Attack',
2436 title => 'Mezzanine',
2439 { key => 'cd_artist_title' }
2442 $cd->cd_to_producer->update_or_create({
2443 producer => $producer,
2449 B<Note>: Make sure to read the documentation of L</find> and understand the
2450 significance of the C<key> attribute, as its lack may skew your search, and
2451 subsequently result in spurious row creation.
2453 B<Note>: Take care when using C<update_or_create> with a table having
2454 columns with default values that you intend to be automatically
2455 supplied by the database (e.g. an auto_increment primary key column).
2456 In normal usage, the value of such columns should NOT be included at
2457 all in the call to C<update_or_create>, even when set to C<undef>.
2459 See also L</find> and L</find_or_create>. For information on how to declare
2460 unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
2464 sub update_or_create {
2466 my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
2467 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2469 my $row = $self->find($cond, $attrs);
2471 $row->update($cond);
2475 return $self->create($cond);
2478 =head2 update_or_new
2482 =item Arguments: \%col_values, { key => $unique_constraint }?
2484 =item Return Value: $rowobject
2488 $resultset->update_or_new({ col => $val, ... });
2490 Like L</find_or_new> but if a row is found it is immediately updated via
2491 C<< $found_row->update (\%col_values) >>.
2495 # In your application
2496 my $cd = $schema->resultset('CD')->update_or_new(
2498 artist => 'Massive Attack',
2499 title => 'Mezzanine',
2502 { key => 'cd_artist_title' }
2505 if ($cd->in_storage) {
2506 # the cd was updated
2509 # the cd is not yet in the database, let's insert it
2513 B<Note>: Make sure to read the documentation of L</find> and understand the
2514 significance of the C<key> attribute, as its lack may skew your search, and
2515 subsequently result in spurious new objects.
2517 B<Note>: Take care when using C<update_or_new> with a table having
2518 columns with default values that you intend to be automatically
2519 supplied by the database (e.g. an auto_increment primary key column).
2520 In normal usage, the value of such columns should NOT be included at
2521 all in the call to C<update_or_new>, even when set to C<undef>.
2523 See also L</find>, L</find_or_create> and L</find_or_new>.
2529 my $attrs = ( @_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {} );
2530 my $cond = ref $_[0] eq 'HASH' ? shift : {@_};
2532 my $row = $self->find( $cond, $attrs );
2533 if ( defined $row ) {
2534 $row->update($cond);
2538 return $self->new_result($cond);
2545 =item Arguments: none
2547 =item Return Value: \@cache_objects | undef
2551 Gets the contents of the cache for the resultset, if the cache is set.
2553 The cache is populated either by using the L</prefetch> attribute to
2554 L</search> or by calling L</set_cache>.
2566 =item Arguments: \@cache_objects
2568 =item Return Value: \@cache_objects
2572 Sets the contents of the cache for the resultset. Expects an arrayref
2573 of objects of the same class as those produced by the resultset. Note that
2574 if the cache is set the resultset will return the cached objects rather
2575 than re-querying the database even if the cache attr is not set.
2577 The contents of the cache can also be populated by using the
2578 L</prefetch> attribute to L</search>.
2583 my ( $self, $data ) = @_;
2584 $self->throw_exception("set_cache requires an arrayref")
2585 if defined($data) && (ref $data ne 'ARRAY');
2586 $self->{all_cache} = $data;
2593 =item Arguments: none
2595 =item Return Value: undef
2599 Clears the cache for the resultset.
2604 shift->set_cache(undef);
2611 =item Arguments: none
2613 =item Return Value: true, if the resultset has been paginated
2621 return !!$self->{attrs}{page};
2628 =item Arguments: none
2630 =item Return Value: true, if the resultset has been ordered with C<order_by>.
2638 return scalar $self->result_source->storage->_extract_order_columns($self->{attrs}{order_by});
2641 =head2 related_resultset
2645 =item Arguments: $relationship_name
2647 =item Return Value: $resultset
2651 Returns a related resultset for the supplied relationship name.
2653 $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
2657 sub related_resultset {
2658 my ($self, $rel) = @_;
2660 $self->{related_resultsets} ||= {};
2661 return $self->{related_resultsets}{$rel} ||= do {
2662 my $rsrc = $self->result_source;
2663 my $rel_info = $rsrc->relationship_info($rel);
2665 $self->throw_exception(
2666 "search_related: result source '" . $rsrc->source_name .
2667 "' has no such relationship $rel")
2670 my $attrs = $self->_chain_relationship($rel);
2672 my $join_count = $attrs->{seen_join}{$rel};
2674 my $alias = $self->result_source->storage
2675 ->relname_to_table_alias($rel, $join_count);
2677 # since this is search_related, and we already slid the select window inwards
2678 # (the select/as attrs were deleted in the beginning), we need to flip all
2679 # left joins to inner, so we get the expected results
2680 # read the comment on top of the actual function to see what this does
2681 $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
2684 #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
2685 delete @{$attrs}{qw(result_class alias)};
2689 if (my $cache = $self->get_cache) {
2690 if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
2691 $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
2696 my $rel_source = $rsrc->related_source($rel);
2700 # The reason we do this now instead of passing the alias to the
2701 # search_rs below is that if you wrap/overload resultset on the
2702 # source you need to know what alias it's -going- to have for things
2703 # to work sanely (e.g. RestrictWithObject wants to be able to add
2704 # extra query restrictions, and these may need to be $alias.)
2706 my $rel_attrs = $rel_source->resultset_attributes;
2707 local $rel_attrs->{alias} = $alias;
2709 $rel_source->resultset
2713 where => $attrs->{where},
2716 $new->set_cache($new_cache) if $new_cache;
2721 =head2 current_source_alias
2725 =item Arguments: none
2727 =item Return Value: $source_alias
2731 Returns the current table alias for the result source this resultset is built
2732 on, that will be used in the SQL query. Usually it is C<me>.
2734 Currently the source alias that refers to the result set returned by a
2735 L</search>/L</find> family method depends on how you got to the resultset: it's
2736 C<me> by default, but eg. L</search_related> aliases it to the related result
2737 source name (and keeps C<me> referring to the original result set). The long
2738 term goal is to make L<DBIx::Class> always alias the current resultset as C<me>
2739 (and make this method unnecessary).
2741 Thus it's currently necessary to use this method in predefined queries (see
2742 L<DBIx::Class::Manual::Cookbook/Predefined searches>) when referring to the
2743 source alias of the current result set:
2745 # in a result set class
2747 my ($self, $user) = @_;
2749 my $me = $self->current_source_alias;
2751 return $self->search(
2752 "$me.modified" => $user->id,
2758 sub current_source_alias {
2761 return ($self->{attrs} || {})->{alias} || 'me';
2764 =head2 as_subselect_rs
2768 =item Arguments: none
2770 =item Return Value: $resultset
2774 Act as a barrier to SQL symbols. The resultset provided will be made into a
2775 "virtual view" by including it as a subquery within the from clause. From this
2776 point on, any joined tables are inaccessible to ->search on the resultset (as if
2777 it were simply where-filtered without joins). For example:
2779 my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
2781 # 'x' now pollutes the query namespace
2783 # So the following works as expected
2784 my $ok_rs = $rs->search({'x.other' => 1});
2786 # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
2787 # def) we look for one row with contradictory terms and join in another table
2788 # (aliased 'x_2') which we never use
2789 my $broken_rs = $rs->search({'x.name' => 'def'});
2791 my $rs2 = $rs->as_subselect_rs;
2793 # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
2794 my $not_joined_rs = $rs2->search({'x.other' => 1});
2796 # works as expected: finds a 'table' row related to two x rows (abc and def)
2797 my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
2799 Another example of when one might use this would be to select a subset of
2800 columns in a group by clause:
2802 my $rs = $schema->resultset('Bar')->search(undef, {
2803 group_by => [qw{ id foo_id baz_id }],
2804 })->as_subselect_rs->search(undef, {
2805 columns => [qw{ id foo_id }]
2808 In the above example normally columns would have to be equal to the group by,
2809 but because we isolated the group by into a subselect the above works.
2813 sub as_subselect_rs {
2816 my $attrs = $self->_resolved_attrs;
2818 my $fresh_rs = (ref $self)->new (
2819 $self->result_source
2822 # these pieces will be locked in the subquery
2823 delete $fresh_rs->{cond};
2824 delete @{$fresh_rs->{attrs}}{qw/where bind/};
2826 return $fresh_rs->search( {}, {
2828 $attrs->{alias} => $self->as_query,
2829 -alias => $attrs->{alias},
2830 -source_handle => $self->result_source->handle,
2832 alias => $attrs->{alias},
2836 # This code is called by search_related, and makes sure there
2837 # is clear separation between the joins before, during, and
2838 # after the relationship. This information is needed later
2839 # in order to properly resolve prefetch aliases (any alias
2840 # with a relation_chain_depth less than the depth of the
2841 # current prefetch is not considered)
2843 # The increments happen twice per join. An even number means a
2844 # relationship specified via a search_related, whereas an odd
2845 # number indicates a join/prefetch added via attributes
2847 # Also this code will wrap the current resultset (the one we
2848 # chain to) in a subselect IFF it contains limiting attributes
2849 sub _chain_relationship {
2850 my ($self, $rel) = @_;
2851 my $source = $self->result_source;
2852 my $attrs = { %{$self->{attrs}||{}} };
2854 # we need to take the prefetch the attrs into account before we
2855 # ->_resolve_join as otherwise they get lost - captainL
2856 my $join = $self->_merge_attr( $attrs->{join}, $attrs->{prefetch} );
2858 delete @{$attrs}{qw/join prefetch collapse group_by distinct select as columns +select +as +columns/};
2860 my $seen = { %{ (delete $attrs->{seen_join}) || {} } };
2863 my @force_subq_attrs = qw/offset rows group_by having/;
2866 ($attrs->{from} && ref $attrs->{from} ne 'ARRAY')
2868 $self->_has_resolved_attr (@force_subq_attrs)
2870 # Nuke the prefetch (if any) before the new $rs attrs
2871 # are resolved (prefetch is useless - we are wrapping
2872 # a subquery anyway).
2873 my $rs_copy = $self->search;
2874 $rs_copy->{attrs}{join} = $self->_merge_attr (
2875 $rs_copy->{attrs}{join},
2876 delete $rs_copy->{attrs}{prefetch},
2880 -source_handle => $source->handle,
2881 -alias => $attrs->{alias},
2882 $attrs->{alias} => $rs_copy->as_query,
2884 delete @{$attrs}{@force_subq_attrs, qw/where bind/};
2885 $seen->{-relation_chain_depth} = 0;
2887 elsif ($attrs->{from}) { #shallow copy suffices
2888 $from = [ @{$attrs->{from}} ];
2892 -source_handle => $source->handle,
2893 -alias => $attrs->{alias},
2894 $attrs->{alias} => $source->from,
2898 my $jpath = ($seen->{-relation_chain_depth})
2899 ? $from->[-1][0]{-join_path}
2902 my @requested_joins = $source->_resolve_join(
2909 push @$from, @requested_joins;
2911 $seen->{-relation_chain_depth}++;
2913 # if $self already had a join/prefetch specified on it, the requested
2914 # $rel might very well be already included. What we do in this case
2915 # is effectively a no-op (except that we bump up the chain_depth on
2916 # the join in question so we could tell it *is* the search_related)
2919 # we consider the last one thus reverse
2920 for my $j (reverse @requested_joins) {
2921 my ($last_j) = keys %{$j->[0]{-join_path}[-1]};
2922 if ($rel eq $last_j) {
2923 $j->[0]{-relation_chain_depth}++;
2929 unless ($already_joined) {
2930 push @$from, $source->_resolve_join(
2938 $seen->{-relation_chain_depth}++;
2940 return {%$attrs, from => $from, seen_join => $seen};
2943 # too many times we have to do $attrs = { %{$self->_resolved_attrs} }
2944 sub _resolved_attrs_copy {
2946 return { %{$self->_resolved_attrs (@_)} };
2949 sub _resolved_attrs {
2951 return $self->{_attrs} if $self->{_attrs};
2953 my $attrs = { %{ $self->{attrs} || {} } };
2954 my $source = $self->result_source;
2955 my $alias = $attrs->{alias};
2957 $attrs->{columns} ||= delete $attrs->{cols} if exists $attrs->{cols};
2960 # build columns (as long as select isn't set) into a set of as/select hashes
2961 unless ( $attrs->{select} ) {
2964 if ( ref $attrs->{columns} eq 'ARRAY' ) {
2965 @cols = @{ delete $attrs->{columns}}
2966 } elsif ( defined $attrs->{columns} ) {
2967 @cols = delete $attrs->{columns}
2969 @cols = $source->columns
2973 if ( ref $_ eq 'HASH' ) {
2976 my $key = /^\Q${alias}.\E(.+)$/
2982 push @colbits, { $key => $value };
2987 # add the additional columns on
2988 foreach (qw{include_columns +columns}) {
2989 if ( $attrs->{$_} ) {
2990 my @list = ( ref($attrs->{$_}) eq 'ARRAY' )
2991 ? @{ delete $attrs->{$_} }
2992 : delete $attrs->{$_};
2994 if ( ref($_) eq 'HASH' ) {
2997 my $key = ( split /\./, $_ )[-1];
2998 my $value = ( /\./ ? $_ : "$alias.$_" );
2999 push @colbits, { $key => $value };
3005 # start with initial select items
3006 if ( $attrs->{select} ) {
3008 ( ref $attrs->{select} eq 'ARRAY' )
3009 ? [ @{ $attrs->{select} } ]
3010 : [ $attrs->{select} ];
3012 if ( $attrs->{as} ) {
3015 ref $attrs->{as} eq 'ARRAY'
3016 ? [ @{ $attrs->{as} } ]
3020 $attrs->{as} = [ map {
3021 m/^\Q${alias}.\E(.+)$/
3024 } @{ $attrs->{select} }
3030 # otherwise we intialise select & as to empty
3031 $attrs->{select} = [];
3035 # now add colbits to select/as
3036 push @{ $attrs->{select} }, map values %{$_}, @colbits;
3037 push @{ $attrs->{as} }, map keys %{$_}, @colbits;
3039 if ( my $adds = delete $attrs->{'+select'} ) {
3040 $adds = [$adds] unless ref $adds eq 'ARRAY';
3041 push @{ $attrs->{select} },
3042 map { /\./ || ref $_ ? $_ : "$alias.$_" } @$adds;
3044 if ( my $adds = delete $attrs->{'+as'} ) {
3045 $adds = [$adds] unless ref $adds eq 'ARRAY';
3046 push @{ $attrs->{as} }, @$adds;
3049 $attrs->{from} ||= [{
3050 -source_handle => $source->handle,
3051 -alias => $self->{attrs}{alias},
3052 $self->{attrs}{alias} => $source->from,
3055 if ( $attrs->{join} || $attrs->{prefetch} ) {
3057 $self->throw_exception ('join/prefetch can not be used with a custom {from}')
3058 if ref $attrs->{from} ne 'ARRAY';
3060 my $join = delete $attrs->{join} || {};
3062 if ( defined $attrs->{prefetch} ) {
3063 $join = $self->_merge_attr( $join, $attrs->{prefetch} );
3066 $attrs->{from} = # have to copy here to avoid corrupting the original
3068 @{ $attrs->{from} },
3069 $source->_resolve_join(
3072 { %{ $attrs->{seen_join} || {} } },
3073 ( $attrs->{seen_join} && keys %{$attrs->{seen_join}})
3074 ? $attrs->{from}[-1][0]{-join_path}
3081 if ( defined $attrs->{order_by} ) {
3082 $attrs->{order_by} = (
3083 ref( $attrs->{order_by} ) eq 'ARRAY'
3084 ? [ @{ $attrs->{order_by} } ]
3085 : [ $attrs->{order_by} || () ]
3089 if ($attrs->{group_by} and ref $attrs->{group_by} ne 'ARRAY') {
3090 $attrs->{group_by} = [ $attrs->{group_by} ];
3093 # generate the distinct induced group_by early, as prefetch will be carried via a
3094 # subquery (since a group_by is present)
3095 if (delete $attrs->{distinct}) {
3096 if ($attrs->{group_by}) {
3097 carp ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
3100 my $storage = $self->result_source->schema->storage;
3101 my $rs_column_list = $storage->_resolve_column_info ($attrs->{from});
3103 my $group_spec = $attrs->{group_by} = [];
3106 for (@{$attrs->{select}}) {
3107 if (! ref($_) or ref ($_) ne 'HASH' ) {
3108 push @$group_spec, $_;
3110 if ($rs_column_list->{$_} and $_ !~ /\./ ) {
3111 # add a fully qualified version as well
3112 $group_index{"$rs_column_list->{$_}{-source_alias}.$_"}++;
3116 # add any order_by parts that are not already present in the group_by
3117 # we need to be careful not to add any named functions/aggregates
3118 # i.e. select => [ ... { count => 'foo', -as 'foocount' } ... ]
3119 for my $chunk ($storage->_extract_order_columns($attrs->{order_by})) {
3121 # only consider real columns (for functions the user got to do an explicit group_by)
3122 my $colinfo = $rs_column_list->{$chunk}
3125 $chunk = "$colinfo->{-source_alias}.$chunk" if $chunk !~ /\./;
3126 push @$group_spec, $chunk unless $group_index{$chunk}++;
3131 $attrs->{collapse} ||= {};
3132 if ( my $prefetch = delete $attrs->{prefetch} ) {
3133 $prefetch = $self->_merge_attr( {}, $prefetch );
3135 my $prefetch_ordering = [];
3137 # this is a separate structure (we don't look in {from} directly)
3138 # as the resolver needs to shift things off the lists to work
3139 # properly (identical-prefetches on different branches)
3141 if (ref $attrs->{from} eq 'ARRAY') {
3143 my $start_depth = $attrs->{seen_join}{-relation_chain_depth} || 0;
3145 for my $j ( @{$attrs->{from}}[1 .. $#{$attrs->{from}} ] ) {
3146 next unless $j->[0]{-alias};
3147 next unless $j->[0]{-join_path};
3148 next if ($j->[0]{-relation_chain_depth} || 0) < $start_depth;
3150 my @jpath = map { keys %$_ } @{$j->[0]{-join_path}};
3153 $p = $p->{$_} ||= {} for @jpath[ ($start_depth/2) .. $#jpath]; #only even depths are actual jpath boundaries
3154 push @{$p->{-join_aliases} }, $j->[0]{-alias};
3159 $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
3161 # we need to somehow mark which columns came from prefetch
3162 $attrs->{_prefetch_select} = [ map { $_->[0] } @prefetch ];
3164 push @{ $attrs->{select} }, @{$attrs->{_prefetch_select}};
3165 push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
3167 push( @{$attrs->{order_by}}, @$prefetch_ordering );
3168 $attrs->{_collapse_order_by} = \@$prefetch_ordering;
3171 # if both page and offset are specified, produce a combined offset
3172 # even though it doesn't make much sense, this is what pre 081xx has
3174 if (my $page = delete $attrs->{page}) {
3176 ($attrs->{rows} * ($page - 1))
3178 ($attrs->{offset} || 0)
3182 return $self->{_attrs} = $attrs;
3186 my ($self, $attr) = @_;
3188 if (ref $attr eq 'HASH') {
3189 return $self->_rollout_hash($attr);
3190 } elsif (ref $attr eq 'ARRAY') {
3191 return $self->_rollout_array($attr);
3197 sub _rollout_array {
3198 my ($self, $attr) = @_;
3201 foreach my $element (@{$attr}) {
3202 if (ref $element eq 'HASH') {
3203 push( @rolled_array, @{ $self->_rollout_hash( $element ) } );
3204 } elsif (ref $element eq 'ARRAY') {
3205 # XXX - should probably recurse here
3206 push( @rolled_array, @{$self->_rollout_array($element)} );
3208 push( @rolled_array, $element );
3211 return \@rolled_array;
3215 my ($self, $attr) = @_;
3218 foreach my $key (keys %{$attr}) {
3219 push( @rolled_array, { $key => $attr->{$key} } );
3221 return \@rolled_array;
3224 sub _calculate_score {
3225 my ($self, $a, $b) = @_;
3227 if (defined $a xor defined $b) {
3230 elsif (not defined $a) {
3234 if (ref $b eq 'HASH') {
3235 my ($b_key) = keys %{$b};
3236 if (ref $a eq 'HASH') {
3237 my ($a_key) = keys %{$a};
3238 if ($a_key eq $b_key) {
3239 return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} ));
3244 return ($a eq $b_key) ? 1 : 0;
3247 if (ref $a eq 'HASH') {
3248 my ($a_key) = keys %{$a};
3249 return ($b eq $a_key) ? 1 : 0;
3251 return ($b eq $a) ? 1 : 0;
3257 my ($self, $orig, $import) = @_;
3259 return $import unless defined($orig);
3260 return $orig unless defined($import);
3262 $orig = $self->_rollout_attr($orig);
3263 $import = $self->_rollout_attr($import);
3266 foreach my $import_element ( @{$import} ) {
3267 # find best candidate from $orig to merge $b_element into
3268 my $best_candidate = { position => undef, score => 0 }; my $position = 0;
3269 foreach my $orig_element ( @{$orig} ) {
3270 my $score = $self->_calculate_score( $orig_element, $import_element );
3271 if ($score > $best_candidate->{score}) {
3272 $best_candidate->{position} = $position;
3273 $best_candidate->{score} = $score;
3277 my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element);
3279 if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) {
3280 push( @{$orig}, $import_element );
3282 my $orig_best = $orig->[$best_candidate->{position}];
3283 # merge orig_best and b_element together and replace original with merged
3284 if (ref $orig_best ne 'HASH') {
3285 $orig->[$best_candidate->{position}] = $import_element;
3286 } elsif (ref $import_element eq 'HASH') {
3287 my ($key) = keys %{$orig_best};
3288 $orig->[$best_candidate->{position}] = { $key => $self->_merge_attr($orig_best->{$key}, $import_element->{$key}) };
3291 $seen_keys->{$import_key} = 1; # don't merge the same key twice
3301 $self->_source_handle($_[0]->handle);
3303 $self->_source_handle->resolve;
3307 =head2 throw_exception
3309 See L<DBIx::Class::Schema/throw_exception> for details.
3313 sub throw_exception {
3316 if (ref $self && $self->_source_handle->schema) {
3317 $self->_source_handle->schema->throw_exception(@_)
3320 DBIx::Class::Exception->throw(@_);
3324 # XXX: FIXME: Attributes docs need clearing up
3328 Attributes are used to refine a ResultSet in various ways when
3329 searching for data. They can be passed to any method which takes an
3330 C<\%attrs> argument. See L</search>, L</search_rs>, L</find>,
3333 These are in no particular order:
3339 =item Value: ( $order_by | \@order_by | \%order_by )
3343 Which column(s) to order the results by.
3345 [The full list of suitable values is documented in
3346 L<SQL::Abstract/"ORDER BY CLAUSES">; the following is a summary of
3349 If a single column name, or an arrayref of names is supplied, the
3350 argument is passed through directly to SQL. The hashref syntax allows
3351 for connection-agnostic specification of ordering direction:
3353 For descending order:
3355 order_by => { -desc => [qw/col1 col2 col3/] }
3357 For explicit ascending order:
3359 order_by => { -asc => 'col' }
3361 The old scalarref syntax (i.e. order_by => \'year DESC') is still
3362 supported, although you are strongly encouraged to use the hashref
3363 syntax as outlined above.
3369 =item Value: \@columns
3373 Shortcut to request a particular set of columns to be retrieved. Each
3374 column spec may be a string (a table column name), or a hash (in which
3375 case the key is the C<as> value, and the value is used as the C<select>
3376 expression). Adds C<me.> onto the start of any column without a C<.> in
3377 it and sets C<select> from that, then auto-populates C<as> from
3378 C<select> as normal. (You may also use the C<cols> attribute, as in
3379 earlier versions of DBIC.)
3381 Essentially C<columns> does the same as L</select> and L</as>.
3383 columns => [ 'foo', { bar => 'baz' } ]
3387 select => [qw/foo baz/],
3394 =item Value: \@columns
3398 Indicates additional columns to be selected from storage. Works the same
3399 as L</columns> but adds columns to the selection. (You may also use the
3400 C<include_columns> attribute, as in earlier versions of DBIC). For
3403 $schema->resultset('CD')->search(undef, {
3404 '+columns' => ['artist.name'],
3408 would return all CDs and include a 'name' column to the information
3409 passed to object inflation. Note that the 'artist' is the name of the
3410 column (or relationship) accessor, and 'name' is the name of the column
3411 accessor in the related table.
3413 =head2 include_columns
3417 =item Value: \@columns
3421 Deprecated. Acts as a synonym for L</+columns> for backward compatibility.
3427 =item Value: \@select_columns
3431 Indicates which columns should be selected from the storage. You can use
3432 column names, or in the case of RDBMS back ends, function or stored procedure
3435 $rs = $schema->resultset('Employee')->search(undef, {
3438 { count => 'employeeid' },
3439 { max => { length => 'name' }, -as => 'longest_name' }
3444 SELECT name, COUNT( employeeid ), MAX( LENGTH( name ) ) AS longest_name FROM employee
3446 B<NOTE:> You will almost always need a corresponding L</as> attribute when you
3447 use L</select>, to instruct DBIx::Class how to store the result of the column.
3448 Also note that the L</as> attribute has nothing to do with the SQL-side 'AS'
3449 identifier aliasing. You can however alias a function, so you can use it in
3450 e.g. an C<ORDER BY> clause. This is done via the C<-as> B<select function
3451 attribute> supplied as shown in the example above.
3457 Indicates additional columns to be selected from storage. Works the same as
3458 L</select> but adds columns to the default selection, instead of specifying
3467 Indicates additional column names for those added via L</+select>. See L</as>.
3475 =item Value: \@inflation_names
3479 Indicates column names for object inflation. That is L</as> indicates the
3480 slot name in which the column value will be stored within the
3481 L<Row|DBIx::Class::Row> object. The value will then be accessible via this
3482 identifier by the C<get_column> method (or via the object accessor B<if one
3483 with the same name already exists>) as shown below. The L</as> attribute has
3484 B<nothing to do> with the SQL-side C<AS>. See L</select> for details.
3486 $rs = $schema->resultset('Employee')->search(undef, {
3489 { count => 'employeeid' },
3490 { max => { length => 'name' }, -as => 'longest_name' }
3499 If the object against which the search is performed already has an accessor
3500 matching a column name specified in C<as>, the value can be retrieved using
3501 the accessor as normal:
3503 my $name = $employee->name();
3505 If on the other hand an accessor does not exist in the object, you need to
3506 use C<get_column> instead:
3508 my $employee_count = $employee->get_column('employee_count');
3510 You can create your own accessors if required - see
3511 L<DBIx::Class::Manual::Cookbook> for details.
3517 =item Value: ($rel_name | \@rel_names | \%rel_names)
3521 Contains a list of relationships that should be joined for this query. For
3524 # Get CDs by Nine Inch Nails
3525 my $rs = $schema->resultset('CD')->search(
3526 { 'artist.name' => 'Nine Inch Nails' },
3527 { join => 'artist' }
3530 Can also contain a hash reference to refer to the other relation's relations.
3533 package MyApp::Schema::Track;
3534 use base qw/DBIx::Class/;
3535 __PACKAGE__->table('track');
3536 __PACKAGE__->add_columns(qw/trackid cd position title/);
3537 __PACKAGE__->set_primary_key('trackid');
3538 __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
3541 # In your application
3542 my $rs = $schema->resultset('Artist')->search(
3543 { 'track.title' => 'Teardrop' },
3545 join => { cd => 'track' },
3546 order_by => 'artist.name',
3550 You need to use the relationship (not the table) name in conditions,
3551 because they are aliased as such. The current table is aliased as "me", so
3552 you need to use me.column_name in order to avoid ambiguity. For example:
3554 # Get CDs from 1984 with a 'Foo' track
3555 my $rs = $schema->resultset('CD')->search(
3558 'tracks.name' => 'Foo'
3560 { join => 'tracks' }
3563 If the same join is supplied twice, it will be aliased to <rel>_2 (and
3564 similarly for a third time). For e.g.
3566 my $rs = $schema->resultset('Artist')->search({
3567 'cds.title' => 'Down to Earth',
3568 'cds_2.title' => 'Popular',
3570 join => [ qw/cds cds/ ],
3573 will return a set of all artists that have both a cd with title 'Down
3574 to Earth' and a cd with title 'Popular'.
3576 If you want to fetch related objects from other tables as well, see C<prefetch>
3579 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
3585 =item Value: ($rel_name | \@rel_names | \%rel_names)
3589 Contains one or more relationships that should be fetched along with
3590 the main query (when they are accessed afterwards the data will
3591 already be available, without extra queries to the database). This is
3592 useful for when you know you will need the related objects, because it
3593 saves at least one query:
3595 my $rs = $schema->resultset('Tag')->search(
3604 The initial search results in SQL like the following:
3606 SELECT tag.*, cd.*, artist.* FROM tag
3607 JOIN cd ON tag.cd = cd.cdid
3608 JOIN artist ON cd.artist = artist.artistid
3610 L<DBIx::Class> has no need to go back to the database when we access the
3611 C<cd> or C<artist> relationships, which saves us two SQL statements in this
3614 Simple prefetches will be joined automatically, so there is no need
3615 for a C<join> attribute in the above search.
3617 C<prefetch> can be used with the following relationship types: C<belongs_to>,
3618 C<has_one> (or if you're using C<add_relationship>, any relationship declared
3619 with an accessor type of 'single' or 'filter'). A more complex example that
3620 prefetches an artists cds, the tracks on those cds, and the tags associated
3621 with that artist is given below (assuming many-to-many from artists to tags):
3623 my $rs = $schema->resultset('Artist')->search(
3627 { cds => 'tracks' },
3628 { artist_tags => 'tags' }
3634 B<NOTE:> If you specify a C<prefetch> attribute, the C<join> and C<select>
3635 attributes will be ignored.
3637 B<CAVEATs>: Prefetch does a lot of deep magic. As such, it may not behave
3638 exactly as you might expect.
3644 Prefetch uses the L</cache> to populate the prefetched relationships. This
3645 may or may not be what you want.
3649 If you specify a condition on a prefetched relationship, ONLY those
3650 rows that match the prefetched condition will be fetched into that relationship.
3651 This means that adding prefetch to a search() B<may alter> what is returned by
3652 traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
3654 my $artist_rs = $schema->resultset('Artist')->search({
3660 my $count = $artist_rs->first->cds->count;
3662 my $artist_rs_prefetch = $artist_rs->search( {}, { prefetch => 'cds' } );
3664 my $prefetch_count = $artist_rs_prefetch->first->cds->count;
3666 cmp_ok( $count, '==', $prefetch_count, "Counts should be the same" );
3668 that cmp_ok() may or may not pass depending on the datasets involved. This
3669 behavior may or may not survive the 0.09 transition.
3681 Makes the resultset paged and specifies the page to retrieve. Effectively
3682 identical to creating a non-pages resultset and then calling ->page($page)
3685 If L<rows> attribute is not specified it defaults to 10 rows per page.
3687 When you have a paged resultset, L</count> will only return the number
3688 of rows in the page. To get the total, use the L</pager> and call
3689 C<total_entries> on it.
3699 Specifies the maximum number of rows for direct retrieval or the number of
3700 rows per page if the page attribute or method is used.
3706 =item Value: $offset
3710 Specifies the (zero-based) row number for the first row to be returned, or the
3711 of the first row of the first page if paging is used.
3717 =item Value: \@columns
3721 A arrayref of columns to group by. Can include columns of joined tables.
3723 group_by => [qw/ column1 column2 ... /]
3729 =item Value: $condition
3733 HAVING is a select statement attribute that is applied between GROUP BY and
3734 ORDER BY. It is applied to the after the grouping calculations have been
3737 having => { 'count(employee)' => { '>=', 100 } }
3743 =item Value: (0 | 1)
3747 Set to 1 to group by all columns. If the resultset already has a group_by
3748 attribute, this setting is ignored and an appropriate warning is issued.
3754 Adds to the WHERE clause.
3756 # only return rows WHERE deleted IS NULL for all searches
3757 __PACKAGE__->resultset_attributes({ where => { deleted => undef } }); )
3759 Can be overridden by passing C<< { where => undef } >> as an attribute
3766 Set to 1 to cache search results. This prevents extra SQL queries if you
3767 revisit rows in your ResultSet:
3769 my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
3771 while( my $artist = $resultset->next ) {
3775 $rs->first; # without cache, this would issue a query
3777 By default, searches are not cached.
3779 For more examples of using these attributes, see
3780 L<DBIx::Class::Manual::Cookbook>.
3786 =item Value: ( 'update' | 'shared' )
3790 Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT