How to insert data only if data doesn't already exist?

Posted by Lost_in_code on Stack Overflow See other posts from Stack Overflow or by Lost_in_code
Published on 2010-06-03T10:01:14Z Indexed on 2010/06/03 10:04 UTC
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sql

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mysql

This is what I'm doing right now:

Execute a query and check if the date to be inserted already exists in a table.

If date doesn't exist:

Another query will insert the date into the table.

How can these two query be combined?

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