September 2, 2014

Avoiding auto-increment holes on InnoDB with INSERT IGNORE

Are you using InnoDB tables on MySQL version 5.1.22 or newer? If so, you probably have gaps in your auto-increment columns. A simple INSERT IGNORE query creates gaps for every ignored insert, but this is undocumented behaviour. This documentation bug is already submitted. Firstly, we will start with a simple question. Why do we have […]

Innodb usability and ease of use.

It always surprised me how little Innodb team seems to think about product usability/ease of use, when it comes to settings, performance management etc. I could understand many things 5 years ago, like a lot of information being available only in hard to parse SHOW INNODB STATUS output or even uglier hacks with creating tables […]

InnoDB auto-inc scalability fixed

There was long played scalability issue with InnoDB auto-increment field. For details check Bug 16979. In short words the problem is in case of insert into table with auto-increment column the special AUTO_INC table level lock is obtained, instead of usual row-level locks. With many concurrent inserted threads this causes serious scalability problems, and in […]