Unique text field in MySQL and php

Posted by Jonathan on Stack Overflow See other posts from Stack Overflow or by Jonathan
Published on 2010-04-07T16:50:36Z Indexed on 2010/04/07 16:53 UTC
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salt

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unique

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mysql

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php

I've created a salt using; md5(rand(0,10000000)); (there is probably a better way?)

There doesn't seem to be possible to make a text field unique in MYSQL. So how do I check if the salt has already been used for a previous user?

Or should I generate the salt based on the current date/time? as it is impossible for 2 users to register at exactly the same time correct?

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