* While this should be rare, this does occur in the dm-is-list specs when testing against the yaml/in_memory adapters. * Possible optimization in the future might be to add #valid? methods to each gt/gte/lt/lte Comparison operator that returns false if the expected value is nil. This will cause the query to never execute, saving the comparison operator from being called when in an invalid state. The object may still need to handle invalid states when called stand-alone through.