In this post I’m going to talk about how TokuDB’s implementation of auto increment works, and contrast it to the behavior of MyISAM and InnoDB. We feel that the TokuDB behavior is easier to understand, more standard-compliant and offers higher performance (especially when implemented with Fractal Tree indexes).

In TokuDB, each table can have an auto-increment column. That column can be used as any part of a key, but it doesn’t have to be part of any key. The value produced by auto incrementing is always greater than the previous maximum value for that column. There are some cases where auto-incremented values are skipped, such as when a transaction aborts, which “uses up” auto-incremented values.

This behavior is close to that required for SQL:2003 (see SQL:2003 at wikipedia), which specifies that each table provides one unnamed sequence which behaves essentially in the way we implemented auto increment. The …

On April 9-10 the National Science Foundation hosted the Workshop on the Science of Power Management (SciPM 2009), where I gave an invited talk. Here I give a brief summary of my talk along with a pointer to the slides.

The talk describes how MySQL with TokuDB can provide a path to more energy-efficient database implementations. It’s a theoretical talk. That is, rather than presenting results from an existing implementation, it provides food for thought about future possibilities.

Here’s an executive summary of the talk.

Disks use a substantial fraction of the computing power in a typical database application. Although different workloads and configurations can give very different values, somewhere around 1/3 to 2/3 of the total energy consumed by the computing unit seems like a good …