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    Why do you want that in the first place? Let the database do what it's meant for. Commented Oct 31, 2011 at 13:57
  • @SLaks: It may be me having picked some old wives tales up about databases but I thought that if you were trying to look up a 50 character string that it would be slower than looking up an int based on that string. Thinking about it you are probably right that if I index the column that it will do what I want and then some. I am still interested in if there is an answer though since getting a checksum or similar I would have thought was a generaly useful thing to do. Commented Oct 31, 2011 at 14:12
  • @Chris, “getting a checksum or similar” is not a generally useful, it's useful for some specific situations. And in each situation you have different requirements for the checksum/hashcode, so you should probably use different algorithm. Commented Oct 31, 2011 at 21:49
  • It is not possible to get a "shorthand" for a long string by computing any sort of "code" (short of literally compressing it). Where would the missing data go? A 32-bit int, for example, will be able to distinguish 2-32 different strings. A 32 character string can come in at least 36^32 different varieties -- and that's for a short string! Commented Oct 31, 2011 at 21:59
  • @KirkWoll: Yup. I wasn't looking for compression, just a hashing algorithm but one that doesn't potentially vary by architecture, etc so I am expecting collisions. I think I was just mistakenly trying to implement a kind of hashbucket system myself which I have now had thoroughly pointed out is wrong. ;-) Commented Nov 1, 2011 at 9:14