my $query;
if (ref $vals[0] eq 'HASH') {
- $query = $vals[0];
+ $query = { %{$vals[0]} };
} elsif (@cols == @vals) {
$query = {};
@{$query}{@cols} = @vals;
} else {
$query = {@vals};
}
+ foreach (keys %$query) {
+ next if m/\./;
+ $query->{$self->{attrs}{alias}.'.'.$_} = delete $query->{$_};
+ }
#warn Dumper($query);
return $self->search($query)->next;
}
with to find the number of elements. If passed arguments, does a search
on the resultset and counts the results of that.
+Note: When using C<count> with C<group_by>, L<DBIX::Class> emulates C<GROUP BY>
+using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do
+not support C<DISTINCT> with multiple columns. If you are using such a
+database, you should only use columns from the main table in your C<group_by>
+clause.
+
=cut
sub count {
my $self = shift;
return $self->search(@_)->count if @_ && defined $_[0];
- $self->throw_exception(
- "Unable to ->count with a GROUP BY"
- ) if defined $self->{attrs}{group_by};
unless (defined $self->{count}) {
+ my $group_by;
+ my $select = { 'count' => '*' };
+ if( $group_by = delete $self->{attrs}{group_by} ) {
+ my @distinct = @$group_by;
+ # todo: try CONCAT for multi-column pk
+ my @pk = $self->result_source->primary_columns;
+ if( scalar(@pk) == 1 ) {
+ my $pk = shift(@pk);
+ my $alias = $self->{attrs}{alias};
+ my $re = qr/^($alias\.)?$pk$/;
+ foreach my $column ( @$group_by ) {
+ if( $column =~ $re ) {
+ @distinct = ( $column );
+ last;
+ }
+ }
+ }
+
+ $select = { count => { 'distinct' => \@distinct } };
+ #use Data::Dumper; die Dumper $select;
+ }
+
my $attrs = { %{ $self->{attrs} },
- select => { 'count' => '*' },
+ select => $select,
as => [ 'count' ] };
# offset, order by and page are not needed to count. record_filter is cdbi
delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/;
($self->{count}) = (ref $self)->new($self->result_source, $attrs)->cursor->next;
+ $self->{attrs}{group_by} = $group_by;
}
return 0 unless $self->{count};
my $count = $self->{count};
=head2 group_by (arrayref)
-A arrayref of columns to group by. Can include columns of joined tables. Note
-note that L</count> doesn't work on grouped resultsets.
+A arrayref of columns to group by. Can include columns of joined tables.
group_by => [qw/ column1 column2 ... /]