Easiest timestamp type to use when grabbing rows from a certain period?
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I have a column in a table which I want to update automatically whenever the rows changes or when I first insert it. I had set it to using the `UNIX_TIMESTAMP` function as I found this the easiest when I wanted to get all rows that are at least a week old or is there an easier/better method.

I could use the `datetime` or `timestamp` types but I wasn't sure how to retrieve the rows that are 7 days old or older.

I understand I just set the `DEFAULT` setting to the respective function such as `UNIX_TIMESTAMP` to update it automatically!?

Thanks!