Gregory Stark <[EMAIL PROTECTED]> writes: > "Heikki Linnakangas" <[EMAIL PROTECTED]> writes: >> Return type of hash* functions is just 32 bits. I wonder if that's wide >> enough >> to avoid accidental collisions? Depends on the application of course...
> Oh, I missed that you were suggesting a UNIQUE index. That seems unsafe to me > even for md5 or its ilk. But that would depend on the application too. md5 is designed to be a signature, remember? If there weren't a very high probability of its output being different for different inputs, it wouldn't be good for anything. The built-in hash functions definitely cannot be relied on to not have collisions, though. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly