my $sub_attrs = { %$attrs };
# extra selectors do not go in the subquery and there is no point of ordering it
- delete $sub_attrs->{$_} for qw/collapse prefetch_select select as order_by/;
+ delete $sub_attrs->{$_} for qw/collapse select _prefetch_select as order_by/;
# if we prefetch, we group_by primary keys only as this is what we would get out of the rs via ->next/->all
# clobber old group_by regardless
$attrs->{group_by} = [ $attrs->{group_by} ];
}
+ # generate the distinct induced group_by early, as prefetch will be carried via a
+ # subquery (since a group_by is present)
+ if (delete $attrs->{distinct}) {
+ $attrs->{group_by} ||= [ grep { !ref($_) || (ref($_) ne 'HASH') } @{$attrs->{select}} ];
+ }
+
$attrs->{collapse} ||= {};
if ( my $prefetch = delete $attrs->{prefetch} ) {
$prefetch = $self->_merge_attr( {}, $prefetch );
my @prefetch =
$source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
- $attrs->{prefetch_select} = [ map { $_->[0] } @prefetch ];
- push @{ $attrs->{select} }, @{$attrs->{prefetch_select}};
+ # we need to somehow mark which columns came from prefetch
+ $attrs->{_prefetch_select} = [ map { $_->[0] } @prefetch ];
+
+ push @{ $attrs->{select} }, @{$attrs->{_prefetch_select}};
push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
push( @{$attrs->{order_by}}, @$prefetch_ordering );
$attrs->{_collapse_order_by} = \@$prefetch_ordering;
}
-
- if (delete $attrs->{distinct}) {
- $attrs->{group_by} ||= [ grep { !ref($_) || (ref($_) ne 'HASH') } @{$attrs->{select}} ];
- }
-
# if both page and offset are specified, produce a combined offset
# even though it doesn't make much sense, this is what pre 081xx has
# been doing
for my $j (@$fromspec) {
next if ref $j ne 'ARRAY';
- next if $j->[0]{-relation_chain_depth} < $cur_depth;
+ next if ($j->[0]{-relation_chain_depth} || 0) < $cur_depth;
my $jpath = $j->[0]{-join_path};
If you specify a condition on a prefetched relationship, ONLY those
rows that match the prefetched condition will be fetched into that relationship.
This means that adding prefetch to a search() B<may alter> what is returned by
-traversing a relationship. So, if you have C<Artist->has_many(CDs)> and you do
+traversing a relationship. So, if you have C<< Artist->has_many(CDs) >> and you do
my $artist_rs = $schema->resultset('Artist')->search({
'cds.year' => 2008,