Timestamp comapriosn
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I am trying to make a clocking system so that people I make websites for can see what I have done when. I have two time stamps in a SQL database.

I want to find out how many hours are between them as I am paid by the hour.
When I query my table, i get the time stamps and assing them to variables

    $clock_in;
    $clock_out;

And i want to find the hours/mins between them.
Thanks