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Search Results for: myisam join queries

Innodb Table Locks

Innodb uses row level locks right ? So if you see locked tables reported in SHOW ENGINE INNODB STATUS you might be confused and rightfully so as Innodb table locking is a bit more complicated …

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How FLUSH TABLES WITH READ LOCK works with Innodb Tables

Many backup tools including Percona Xtrabackup, MyLVMBackup and others use FLUSH TABLES WITH READ LOCK to temporary make MySQL read only. In many cases the period for which server has to be made read only …

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Troubleshooting MySQL Upgrade Performance Regressions

So lets say you upgraded from MySQL 5.1 to Percona Server 5.5 and instead of expected performance improvement you see your performance being worse. What should you do ? First if you followed MySQL upgrade …

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Shard-Query turbo charges Infobright community edition (ICE)

Shard-Query is an open source tool kit which helps improve the performance of queries against a MySQL database by distributing the work over multiple machines and/or multiple cores. This is similar to the divide and …

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TokuDB FAQ

by:

Links to the FAQ Sections can be found here: General Information Open Source Technical Details Best Practices and Tools General Information ANY CHARACTER HERE 1.    What is TokuDB? TokuDB is an ACID compliant storage engine for …

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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 …

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How fast is FLUSH TABLES WITH READ LOCK?

A week or so ago at the MySQL conference, I visited one of the backup vendors in the Expo Hall. I started to chat with them about their MySQL backup product. One of the representatives …

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New OLAP Wikistat benchmark: Introduction and call for feedbacks

I’ve seen my posts on Ontime Air traffic and Star Schema Benchmark got a lot of interest (links: https://www.percona.com/blog/2010/01/07/star-schema-bechmark-infobright-infinidb-and-luciddb/ https://www.percona.com/blog/2009/10/02/analyzing-air-traffic-performance-with-infobright-and-monetdb/ https://www.percona.com/blog/2009/10/26/air-traffic-queries-in-luciddb/ https://www.percona.com/blog/2009/11/02/air-traffic-queries-in-infinidb-early-alpha/ ). However benchmarks by itself did not cover all cases I would want, …

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Analyzing air traffic performance with InfoBright and MonetDB

Accidentally me and Baron played with InfoBright (see https://www.percona.com/blog/2009/09/29/quick-comparison-of-myisam-infobright-and-monetdb/) this week. And following Baron’s example I also run the same load against MonetDB. Reading comments to Baron’s post I tied to load the same data …

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Guidance for MySQL Optimizer Developers

I spend large portion of my life working on MySQL Performance Optimization and so MySQL Optimizer is quite important to me. For probably last 10 years I chased first Monty and later Igor with Optimizer …

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