using the difference between two dates in a WHERE clause
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I'm trying to filter a SELECT query between NOW() and NOW - interval 10 minute(?), but i can't seem to get this to work, and it's given me a few questions on the topic.

I've looked through some documentation online, and alot of questions on stackoverflow but non of the solutions give me what i need. Looking at the TIMEDIFF and TIMESTAMPDIFF documentation, i only see it used like this;

    SELECT TIMESTAMPDIFF(SECOND,'2007-12-30 12:01:01','2007-12-31 10:02:00'); 

However i don't want to just select the time difference, i want to use it in a query as a WHERE clause, something like;

    SELECT * FROM tableName WHERE (the time difference betweeen NOW() and the stored timestamp is less than x minutes);

Is there a particular data type i need to set my column to?
How can i use the TIMEDIFF / TIMESTAMPDIFF correctly, and if these are not the correct methods i should be using, what is?