=head1 OVERLOADING
If a resultset is used in a numeric context it returns the L</count>.
-However, if it is used in a booleand context it is always true. So if
+However, if it is used in a boolean context it is always true. So if
you want to check if a resultset has any results use C<if $rs != 0>.
C<if $rs> will always be true.
$rows = $self->get_cache;
}
+ # reset the selector list
+ if (List::Util::first { exists $attrs->{$_} } qw{columns select as}) {
+ delete @{$our_attrs}{qw{select as columns +select +as +columns include_columns}};
+ }
+
my $new_attrs = { %{$our_attrs}, %{$attrs} };
# merge new attrs into inherited
- foreach my $key (qw/join prefetch +select +as bind/) {
+ foreach my $key (qw/join prefetch +select +as +columns include_columns bind/) {
next unless exists $attrs->{$key};
$new_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key});
}
- if (List::Util::first { exists $new_attrs->{$_} } qw{select as columns}) {
- delete $new_attrs->{$_} for (qw{+select +as +columns});
- }
-
my $cond = (@_
? (
(@_ == 1 || ref $_[0] eq "HASH")
# in ::Relationship::Base::search_related (the row method), and furthermore
# the relationship is of the 'single' type. This means that the condition
# provided by the relationship (already attached to $self) is sufficient,
- # as there can be only one row in the databse that would satisfy the
+ # as there can be only one row in the database that would satisfy the
# relationship
}
else {
=head2 search_related_rs
This method works exactly the same as search_related, except that
-it guarantees a restultset, even in list context.
+it guarantees a resultset, even in list context.
=cut
=item B<Note>
-As of 0.08100, this method enforces the assumption that the preceeding
+As of 0.08100, this method enforces the assumption that the preceding
query returns only one row. If more than one row is returned, you will receive
a warning:
],
},
{ artistid => 5, name => 'Angsty-Whiny Girl', cds => [
- { title => 'My parents sold me to a record company' ,year => 2005 },
+ { title => 'My parents sold me to a record company', year => 2005 },
{ title => 'Why Am I So Ugly?', year => 2006 },
{ title => 'I Got Surgery and am now Popular', year => 2007 }
],
[qw/artistid name/],
[100, 'A Formally Unknown Singer'],
[101, 'A singer that jumped the shark two albums ago'],
- [102, 'An actually cool singer.'],
+ [102, 'An actually cool singer'],
]);
Please note an important effect on your data when choosing between void and
B<keyed on the relationship name>. If the relationship is of type C<multi>
(L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
The process will correctly identify columns holding foreign keys, and will
-transparrently populate them from the keys of the corresponding relation.
+transparently populate them from the keys of the corresponding relation.
This can be applied recursively, and will work correctly for a structure
with an arbitrary depth and width, as long as the relationships actually
exists and the correct column data has been supplied.
return !!$self->{attrs}{page};
}
+=head2 is_ordered
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: true, if the resultset has been ordered with C<order_by>.
+
+=back
+
+=cut
+
+sub is_ordered {
+ my ($self) = @_;
+ return scalar $self->result_source->storage->_parse_order_by($self->{attrs}{order_by});
+}
+
=head2 related_resultset
=over 4
return ($self->{attrs} || {})->{alias} || 'me';
}
+=head2 as_subselect_rs
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: $resultset
+
+=back
+
+Act as a barrier to SQL symbols. The resultset provided will be made into a
+"virtual view" by including it as a subquery within the from clause. From this
+point on, any joined tables are inaccessible to ->search on the resultset (as if
+it were simply where-filtered without joins). For example:
+
+ my $rs = $schema->resultset('Bar')->search({'x.name' => 'abc'},{ join => 'x' });
+
+ # 'x' now pollutes the query namespace
+
+ # So the following works as expected
+ my $ok_rs = $rs->search({'x.other' => 1});
+
+ # But this doesn't: instead of finding a 'Bar' related to two x rows (abc and
+ # def) we look for one row with contradictory terms and join in another table
+ # (aliased 'x_2') which we never use
+ my $broken_rs = $rs->search({'x.name' => 'def'});
+
+ my $rs2 = $rs->as_subselect_rs;
+
+ # doesn't work - 'x' is no longer accessible in $rs2, having been sealed away
+ my $not_joined_rs = $rs2->search({'x.other' => 1});
+
+ # works as expected: finds a 'table' row related to two x rows (abc and def)
+ my $correctly_joined_rs = $rs2->search({'x.name' => 'def'});
+
+Another example of when one might use this would be to select a subset of
+columns in a group by clause:
+
+ my $rs = $schema->resultset('Bar')->search(undef, {
+ group_by => [qw{ id foo_id baz_id }],
+ })->as_subselect_rs->search(undef, {
+ columns => [qw{ id foo_id }]
+ });
+
+In the above example normally columns would have to be equal to the group by,
+but because we isolated the group by into a subselect the above works.
+
+=cut
+
+sub as_subselect_rs {
+ my $self = shift;
+
+ return $self->result_source->resultset->search( undef, {
+ alias => $self->current_source_alias,
+ from => [{
+ $self->current_source_alias => $self->as_query,
+ -alias => $self->current_source_alias,
+ -source_handle => $self->result_source->handle,
+ }]
+ });
+}
+
# This code is called by search_related, and makes sure there
# is clear separation between the joins before, during, and
# after the relationship. This information is needed later
will fail miserably.
To get around this limitation, you can supply literal SQL to your
-C<select> attibute that contains the C<AS alias> text, eg:
+C<select> attribute that contains the C<AS alias> text, e.g.
select => [\'myfield AS alias']
C<prefetch> can be used with the following relationship types: C<belongs_to>,
C<has_one> (or if you're using C<add_relationship>, any relationship declared
with an accessor type of 'single' or 'filter'). A more complex example that
-prefetches an artists cds, the tracks on those cds, and the tags associted
+prefetches an artists cds, the tracks on those cds, and the tags associated
with that artist is given below (assuming many-to-many from artists to tags):
my $rs = $schema->resultset('Artist')->search(
=back
-Specifes the maximum number of rows for direct retrieval or the number of
+Specifies the maximum number of rows for direct retrieval or the number of
rows per page if the page attribute or method is used.
=head2 offset