July 24, 2014

Derived Tables and Views Performance

Starting MySQL 4.1, MySQL had support for what is called derived tables, inline views or basically subselects in the from clause. In MySQL 5.0 support for views was added. These features are quite related to each other but how do they compare in terms of performance ?

MySQL wins C’T Database Contest

Today MySQL published the press release with results of Database Contest (results on German available here http://www.mysql.de/ct-dbcontest). Peter and me spent quite some time working on this project while being employed by MySQL and it is great to see results finally publicly available. The story began about year ago when C’T magazine had called for […]

Watch out for Marketing benchmarks

Whenever I see benchmark results I try to understand if it is technical benchmark – made by people seeking the truth or it is done by Marketing department to wash your brains. Watch out. Whenever you treat marketing benchmarks as technical ones, you make make wrong decision. Take a look at MySQL 5.0 Benchmarks Whitepaper […]

Using LVM for MySQL Backup and Replication Setup

If someone asks me about MySQL Backup advice my first question would be if they have LVM installed or have some systems with similar features set for other operation systems. Veritas File System can do it for Solaris. Most SAN systems would work as well. What is really needed is ability to create atomic snapshot […]

MySQL Performance Forum: Hot Topics

As I already announced last week I started MySQL Performance Forums project focusing on MySQL Performance discussions as it names says. I spend planty of time replying questions and thought it would be good idea to provide weekly overviews of most interesting topic discussed. Here is the list for last week: Ways to perform full […]

SysBench – benchmark tool

Sysbench is benchmark developed by Alexey Kopytov (software engineer @ MySQL AB) – http://sysbench.sourceforge.net/ and I want to write a short intro about this tool as sysbench is one of software for my everyday use. For example, SUN published their Solaris vs RedHat stuff based on sysbench’s results (Peter and me provided performance consutling for […]

Duplicate indexes and redundant indexes

About every second application I look at has some tables which have redundant or duplicate indexes so its the time to speak about these a bit. So what is duplicate index ? This is when table has multiple indexes defined on the same columns. Sometimes it is indexes with different names, sometimes it is different […]

MySQL: Followup on UNION for query optimization, Query profiling

Few days ago I wrote an article about using UNION to implement loose index scan. First I should mention double IN also works same way so you do not have to use the union. So changing query to:

So as you see there are really different types of ranges in MySQL. IN range allows […]

Database problems in MySQL/PHP Applications

Article about database design problems is being discussed by Kristian. Both article itself and responce cause mixed feellings so I decided it is worth commenting: 1. Using mysql_* functions directly This is probably bad but I do not like solutions proposed by original article ether. PEAR is slow as well as other complex conectors. I […]

MySQL Server Upgrade

Today I’ve upgraded MySQL Server on the host running MySQL Performance Blog. MySQL 4.1.12 was running here for well over a year before that. Why Have not I upgraded before ? Well because it just worked fine. Yes I know there were some security fixes but I have dedicated server with remote MySQL access closed […]