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Search Results for: myisam pack indexes

Ultimate MySQL variable and status reference list

I am constantly referring to the amazing MySQL manual, especially the option and variable reference table. But just as frequently, I want to look up blog posts on variables, or look for content in the …


Avoiding Fragmentation with Fractal Trees

Summary B-trees suffer from fragmentation. Fragmentation causes headaches — in query performance and space used. Solutions, like dump and reload or OPTIMIZE TABLE are a pain and not always effective. Fractal trees don’t fragment. So …


How Percona does a MySQL Performance Audit

Our customers or prospective customers often ask us how we do a performance audit (it’s our most popular service). I thought I should write a blog post that will both answer their question, so I …


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 …


Innodb Performance Optimization Basics

Note: There is an updated post on this topic here. Interviewing people for our Job Openings I like to ask them a basic question – if you have a server with 16GB of RAM which …


Using CHAR keys for joins, how much is the overhead ?

I prefer to use Integers for joins whenever possible and today I worked with client which used character keys, in my opinion without a big need. I told them this is suboptimal but was challenged …


Trying Archive Storage Engine

Today I noticed one of server used for web request profiling stats logging is taking about 2GB per day for logs, which are written in MyISAM table without indexes. So I thought it is great …


Why MySQL could be slow with large tables ?

If you’ve been reading enough database related forums, mailing lists or blogs you probably heard complains about MySQL being unable to handle more than 1.000.000 (or select any other number) rows by some of the …


Descending indexing and loose index scan

Comments to my previous posts, especially this one by Gokhan inspired me to write a bit about descending indexes and about loose index scan, or what Gokhan calls “better range” support. None of these are …


My Innodb Feature wishes

At Users Conference Heikki did good presentation about Innodb planned features. I did not see some of big and tiny wishes listed so I was making notes. Here is what I’d like to see Packed …