$self->simplify_joins( \%simplifiedResult, $joinSpec, \%requiredSetOfRelations || undef);

Take all data in $joinSpec (which can be anything DBIC will accept, which includes hashes and arrays) and eliminate any relation not mentioned in \%requiredSetOfRelations. If %requiredSetOfRelations is undef, no relations are eliminated.

This function converts things like [ { a => b }, { a => { b => c } }, a, a => [ d, f ], ] into { a => { b => { c => {}, }, d => {}, f => {} } } resulting in a minimum of joined tables.

This routine would be a little nicer if the output were { a => [ { b => c }, d, f ] } but that would be a lot of work, and nothing to gain.

Note that for DBIC, regardless of nesting, the relations must each have unique names, which is why %requiredSetOfRelations is a one-level hash rather than a tree of hashes. However, the joins must be specified to DBIC as a tree.

unless (ref($item)) {
	$hash->{$item} = 1;
	return $hash;
}

if (ref($item) eq 'HASH') {
	foreach my $i (keys %$item, values %$item) {
		$self->addToFlatHashref($hash,$i);
	}
	return $hash;
}

if (ref($item) eq 'ARRAY') {
	foreach my $i (@$item) {
		$self->addToFlatHashref($hash,$i);
	}
	return $hash;
}

return $hash;
}