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MySQL Indexing Best Practices: Webinar Questions Followup

I had a lot of questions on my MySQL Indexing: Best Practices Webinar (both recording and slides are available now) We had lots of questions. I did not have time to answer some and others …


Multi Column indexes vs Index Merge

The mistake I commonly see among MySQL users is how indexes are created. Quite commonly people just index individual columns as they are referenced in where clause thinking this is the optimal indexing strategy. For …


Illustrating Primary Key models in InnoDB and their impact on disk usage

On a recent engagement I worked with a customer who makes extensive use of UUID() values for their Primary Key and stores it as char(36), and their row count on this example table has grown to …


MySQL Partitioning – can save you or kill you

I wanted for a while to write about using MySQL Partitioning for Performance Optimization and I just got a relevant customer case to illustrate it. First you need to understand how partitions work internally. Partitions …


Recovering Innodb table Corruption

Assume you’re running MySQL with Innodb tables and you’ve got crappy hardware, driver bug, kernel bug, unlucky power failure or some rare MySQL bug and some pages in Innodb tablespace got corrupted. In such cases …


Heikki Tuuri Innodb answers – Part I

Its almost a month since I promised Heikki Tuuri to answer Innodb Questions. Heikki is a busy man so I got answers to only some of the questions but as people still poking me about …


Working with large data sets in MySQL

What does working with large data sets in mySQL teach you ? Of course you have to learn a lot about query optimization, art of building summary tables and tricks of executing queries exactly as …


Predicting how long data load would take

I had this question asked many times during last week, and there is really no easy answer. There are just way too many variables to consider especially while loading large schemas with a lot of …


To UUID or not to UUID ?

Brian recently posted an article comparing UUID and auto_increment primary keys, basically advertising to use UUID instead of primary keys. I wanted to clarify this a bit as I’ve seen it being problems in so …


Long PRIMARY KEY for Innodb tables

I’ve written and spoke a lot about using short PRIMARY KEYs with Innodb tables due to the fact all other key will refer to the rows by primary key. I also recommended to use sequential …