=head1 DESCRIPTION
-DBIx::Class is faster than older ORMs like Class::DBI but it still isn't
+DBIx::Class is faster than older ORMs like Class::DBI but it still isn't
designed primarily for speed. Sometimes you need to quickly retrieve the data
from a massive resultset, while skipping the creation of fancy row objects.
Specifying this class as a C<result_class> for a resultset will change C<< $rs->next >>
#
# Generally people use this to gain as much speed as possible. If a new &mk_hash is
# implemented, it should be benchmarked using the maint/benchmark_hashrefinflator.pl
-# script (in addition to passing all tests of course :). Additional instructions are
-# provided in the script itself.
-#
+# script (in addition to passing all tests of course :)
# This coderef is a simple recursive function
-# Arguments: ($me, $prefetch) from inflate_result() below
+# Arguments: ($me, $prefetch, $is_root) from inflate_result() below
my $mk_hash;
$mk_hash = sub {
- if (ref $_[0] eq 'ARRAY') { # multi relationship
- return [ map { $mk_hash->(@$_) || () } (@_) ];
- }
- else {
- my $hash = {
- # the main hash could be an undef if we are processing a skipped-over join
- $_[0] ? %{$_[0]} : (),
-
- # the second arg is a hash of arrays for each prefetched relation
- map
- { $_ => $mk_hash->( @{$_[1]->{$_}} ) }
- ( $_[1] ? (keys %{$_[1]}) : () )
- };
-
- # if there is at least one defined column consider the resultset real
- # (and not an emtpy has_many rel containing one empty hashref)
- # an empty arrayref is an empty multi-sub-prefetch - don't consider
- # those either
- for (values %$hash) {
- if (ref $_ eq 'ARRAY') {
- return $hash if @$_;
- }
- elsif (defined $_) {
- return $hash;
- }
- }
-
- return undef;
- }
+
+ my $hash = {
+ # the main hash could be an undef if we are processing a skipped-over join
+ $_[0] ? %{$_[0]} : (),
+
+ # the second arg is a hash of arrays for each prefetched relation
+ map {
+ ref $_[1]->{$_}[0] eq 'ARRAY' # multi rel or not?
+ ? ( $_ => [ map
+ { $mk_hash->(@$_) || () }
+ @{$_[1]->{$_}}
+ ] )
+ : ( $_ => $mk_hash->( @{$_[1]->{$_}} ) )
+
+ } ( $_[1] ? ( keys %{$_[1]} ) : () )
+ };
+
+ # if there is at least one defined column *OR* we are at the root of
+ # the resultset - consider the result real (and not an emtpy has_many
+ # rel containing one empty hashref)
+ # an empty arrayref is an empty multi-sub-prefetch - don't consider
+ # those either
+ return $hash if $_[2];
+
+ for (values %$hash) {
+ return $hash if (
+ defined $_
+ and
+ (ref $_ ne 'ARRAY' or scalar @$_)
+ );
+ }
+
+ return undef;
};
=head1 METHODS
# inflate_result is invoked as:
# HRI->inflate_result ($resultsource_instance, $main_data_hashref, $prefetch_data_hashref)
sub inflate_result {
- return $mk_hash->($_[2], $_[3]);
+ return $mk_hash->($_[2], $_[3], 'is_root');
}
my $cds = $artist->cds;
$cds->result_class('DBIx::Class::ResultClass::HashRefInflator');
- my $first = $cds->first;
+ my $first = $cds->first;
-C<$first> will B<not> be a hashref, it will be a normal CD row since
+C<$first> will B<not> be a hashref, it will be a normal CD row since
HashRefInflator only affects resultsets at inflation time, and prefetch causes
relations to be inflated when the master C<$artist> row is inflated.