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Search Results for: optimize access select in query

Profiling MySQL queries from Performance Schema

When optimizing queries and investigating performance issues, MySQL comes with built in support for profiling queries aka SET profiling = 1; . This is already awesome and simple to use, but why the PERFORMANCE_SCHEMA alternative? Because profiling will be …

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TokuDB Table Optimization Improvements

Section I: Fractal Tree and Optimization Overview Tokutek’s Fractal Tree® technology provides fast performance by injecting small messages into buffers inside the Fractal Tree index. This allows writes to be batched, thus eliminating I/O that is …

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MySQL 5.6 Transportable Tablespaces best practices

In MySQL 5.6 Oracle introduced a Transportable Tablespace feature (copying tablespaces to another server) and Percona Server adopted it for partial backups which means you can now take individual database or table backups and your …

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MySQL upgrade best practices

MySQL upgrades are necessary tasks and we field a variety of questions here at Percona Support regarding MySQL upgrade best practices. This post highlights recommended ways to upgrade MySQL in different scenarios. Why are MySQL …

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Q&A: Common (but deadly) MySQL Development Mistakes

On Wednesday I gave a presentation on “How to Avoid Common (but Deadly) MySQL Development Mistakes” for Percona MySQL Webinars. If you missed it, you can still register to view the recording and my slides. Thanks to …

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How rows_sent can be more than rows_examined?

When looking at queries that are candidates for optimization I often recommend that people look at rows_sent and rows_examined values as available in the slow query log (as well as some other places). If rows_examined …

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8 common (but deadly) MySQL operations mistakes and how to avoid them

January 22 I gave a presentation on “How to Avoid Common (but Deadly) MySQL Operations Mistakes” for Percona MySQL Webinars. If you missed it, you can still register to view the recording and my slides. …

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Generating test data for MySQL tables

One of the common tasks requested by our support customers is to optimize slow queries. We normally ask for the table structure(s), the problematic query and sample data to be able to reproduce the problem …

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Multiple column index vs multiple indexes with MySQL 5.6

A question often comes when talking about indexing: should we use multiple column indexes or multiple indexes on single columns? Peter Zaitsev wrote about it back in 2008 and the conclusion then was that a multiple …

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Lock Diagnostics and Index Usage Statistics in TokuMX v1.2.1

TokuMX v1.2.1 introduces two simple new features to help you understand the performance characteristics of your database: lock diagnostics and index usage statistics. We’d like to take you through a few examples of what these …

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