The value you get by taking the difference of two timestamps is not a timestamp, but an intervall - and that intervall cannot be inserted as just hours - a timestamp is a defined moment in time, not an intervall - as I mentioned here you are simply using the wrong type for that column.

Please stop spamming the monastery with your rubbish postings - read

• Welcome to the Monastery! Make yourself at home.
• How (Not) To Ask A Question

and please above all, read the documentation for the tools you use, namely MySQL in this case, and try to understand the problem you are about to solve before you come up with solutions that aren't likely to work because you don't understand the problem at hand - that seems to be the case here.

I'm a bit fed up with your behaviour here - posting, multiple times, without content, in the wrong sections, creating new accounts to make the same mistakes again - you are misusing a wonderful place, and with that you are taking away from yourself the opportunity to learn something from all the wonderful, helpful poeple here - kind of sad...

---

---

• Are you posting in the right place? Check out Where do I post X? to know for sure.
• Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:

  <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>

• Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
• Want more info? How to link or How to display code and escape characters are good places to start.