zendframework/zf2 — pull request #991 by rsandrea (2012-04-01 04:17:13+00:00)
Title: $left and $right on Sql\Predicate\Operator.php should compare to null

$left and $right should be compared to null while validating, because if you try to create a sentence like : where field = 0, $right will be equal to 0 which will make line 80 evaluate to false, never calling $this->setRight($right)