Thursday, December 20, 2012

Gluh on InnoDB extended secondary keys

Sergey Glukhov (Gluh) recently wrote an interesting blog about InnoDB secondary key improvements in MySQL 5.6. His blog isn't aggregated to but certainly deserves some attention. 

Here it is: InnoDB, extended secondary keys.

Monday, December 17, 2012

Favorite MySQL 5.6 features: an optimizer perspective

There are so many exciting new features in MySQL 5.6 that I almost don't know where to start. To mention a few, MySQL's multi-core scalability has been significantly improved to meet modern hardware, InnoDB has better index statistics, much better performance, and online ALTER, replication has multi-threaded slaves and global transaction identifiers, performance schema has added capabilities to provide a much more detailed view of what's bogging a server down, and more... much more.

However, my prime interest is the optimizer, which is why I've compiled a list of my favorite new optimizer features in 5.6. Here goes:

New ways to understand query plans:
The most common requests from DBAs is to get more information to understand how and why MySQL behaves like it does. You can come a very long way at squeezing performance out of MySQL if you can answer questions like "What Query Execution Plan (QEP) did the server decide to use?" and "Why was this QEP picked?". In this department, MySQL 5.6 delivers a bunch of new features.