Comments on Shreeni's Tech Log: Conditional MySQL statements: Lifesaver on occasio...

@Shreeni - So you take advantage of the fact that ...

2011-03-08T16:56:06.657-08:00

@Shreeni - So you take advantage of the fact that you are most surely to get hits on the page? Or do you've a combination of the cron as well as the conditional updates on the DB?

Anyways, my point was that if the traffic isn't high and the counter solely relies on the conditional update, we might have incorrect results.

@Gokul A: Haven't I written about the cron job...

2011-03-07T23:52:48.765-08:00

@Gokul A: Haven't I written about the cron job you would have to run each night? Wouldn't that update both the cases you are mentioning? This solution is deployed on a very high traffic site with millions of users and it works, so if the conditions you mention are definitely handled - it is a different matter that I might be missing a step in this blog entry (though I don't see what it is when I am reading it presently.)

The solution doesn't handle the count cleanly ...

2011-03-07T21:45:12.387-08:00

The solution doesn't handle the count cleanly from midnight - till the first page view occurs.

Case 1 - What happens when a particular page doesn't receive a hit till late evening. You'll be showing wrong values.
Case 2 - A page doesn't receive clicks for an entire day. The calculations will be plain wrong.

You can do the same by "Insert ... on duplica...

2010-01-18T05:45:54.693-08:00

You can do the same by "Insert ... on duplicate update" construct in mysql (http://dev.mysql.com/doc/refman/5.0/en/insert-on-duplicate.html)

-Shanky