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From: Willem <willem@toad.stack.nl>
Newsgroups: comp.lang.java.programmer,comp.programming,comp.lang.java.databases
Subject: Re: Storing large strings for future equality checks
Date: Wed, 8 Jun 2011 17:28:44 +0000 (UTC)
Organization: Stack Usenet News Service
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markspace wrote:
) On 6/8/2011 9:35 AM, Abu Yahya wrote:
)> I considered using an SHA-512 hash of these strings and storing them in
)> the database. However, while these will save on storage space, it will
)> take time to do the hashing before comparing an incoming string. So I'm
)> still wasting time. (Collisions due to hashing will not be a problem,
)> since an occasional false positive will not be fatal for my application).
)
) You have to store the whole string.  Even if the SHA-512 hash codes are 
) equal, it could be that the strings are different.  You'll have to 
) eventually compare the raw string, even if the SHA is used as a 
) quick-out case.

No he doesn't.  Read again.  Especially the last bit between parentheses.


SaSW, Willem
-- 
Disclaimer: I am in no way responsible for any of the statements
            made in the above text. For all I know I might be
            drugged or something..
            No I'm not paranoid. You all think I'm paranoid, don't you !
#EOT