script termination due to memory_limit

Hi, Thanks for the responses to my earlier question. However the suggestions haven't solved the problem. I think I've finally narrowed the problem down to this : The script executes perfectly well as many times as needed, till I run a rather large query when the memory limit gets exceeded. After this, no query howsoever small will execute -- the 'memory limit exceeded' error keeps appearing each time. What I would like to know is : What is the cleanup procedure in case of a script termination due to memory_limit being exceeded ? Does the memory being consumed by the script get released? Warm regards Gunjan