Search Results for: where

Where to get a BZR tree of the latest MySQL releases

I just posted this to the MySQL Internals mailing list: Hi all, Like many of you, I’m disappointed that the bzr trees for MySQL are out of sync with the tarball source and binary releases from Oracle. Since Oracle has been silent on this, and this is a recurring problem, I’ve decided to attempt to […]

Where Percona software goes before it’s released

Where does software go while it’s waiting for release? The answer is: our experimental repository! For anywhere from a few days to a week before we release them, we stage our software releases in the TESTING download area and in separate software repositories for Debian/Ubuntu and CentOS/RHEL. This is so that we can co-ordinate things such […]

Where does HandlerSocket really save you time?

HandlerSocket has really generated a lot of interest because of the dual promises of ease-of-use and blazing-fast performance. The performance comes from eliminating CPU consumption. Akira Higuchi’s HandlerSocket presentation from a couple of months back had some really good profile results for libmysql versus libhsclient (starting at slide 15). Somebody in the audience at Percona […]

Is there a performance difference between JOIN and WHERE?

I’ve heard this question a lot, but never thought to blog about the answer. “Is there a performance difference between putting the JOIN conditions in the ON clause or the WHERE clause in MySQL?” No, there’s no difference. The following queries are algebraically equivalent inside MySQL and will have the same execution plan.

Personally, […]

Where to get recent MySQL version ?

As you might noticed there are no recent MySQL Community versions available for download from MySQL Download Area This applies both to binaries (which is expected with new polices) but also to the source files which were promised to be available. So what is if you would like to use recent MySQL code while staying […]

Store UUID in an optimized way

A few years ago Peter Zaitsev, in a post titled “To UUID or not to UUID,” wrote: “There is timestamp based part in UUID which has similar properties to auto_increment and which could be used to have values generated at same point in time physically local in BTREE index.” For this post I’ve rearranged the timestamp part […]

InnoDB’s multi-versioning handling can be Achilles’ heel

I believe InnoDB storage engine architecture is great for a lot of online workloads, however, there are no silver bullets in technology and all design choices have their trade offs. In this blog post I’m going to talk about one important InnoDB limitation that you should consider. InnoDB is a multiversion concurrency control (MVCC) storage […]