Re: Inserting at Extreme Volumes

[Jonathan Stephens]

Just so there's no misunderstanding - it's possible to use HOUR() as a partitioning function, but (unlike TO_DAYS() and YEAR()) it's not optimised at this time.

Part of the problem is that HOUR() is not strictly increasing or strictly decreasing, and changing its behaviour in this regard would likely break existing apps. We'd have to add a TO_HOURS() function that returns the number of hours since the Unix Epoch (and so would be strictly increasing). You might want to check the bugs system to see if someone's filed a feature request for this, and if they haven't, file one. (Note that MySQL 5.1 is now in beta which means "no new features", so this couldn't be added before 5.2.)

Jon Stephens
MySQL Documentation Team @ Oracle

MySQL Dev Zone
MySQL Server Documentation
Oracle