This caching can be useful in some applications, but it can also cause problems and should be used with care. If the cached "$sth" being returned is active (i.e., is a "SELECT" that may still have data to be fetched) then a warning will be generated and "finish" will be called for you. The warning can be suppressed by setting "$allow_active" to true. The cache can be accessed (and cleared) via the the CachedKids entry elsewhere in this