Many good suggestions concerning unique.

Another technique is available for checking whether a given value appears in a column, without any needing to fetch any data from your backend, and that is: 

  select 1 from mytable where mycol='foo'

[download]

You'll either get a row back, or nothing. In the general case, this is about as cheap as it gets.

--
g r i n d e r

In reply to Re: Checking for Dupes in MySQL by grinder
in thread Checking for Dupes in MySQL by bagelesque

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