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Search Results for: mysql explain plan

Advanced Query Tuning in MySQL 5.6 and MySQL 5.7 Webinar: Q&A

Thank you for attending my July 22 webinar titled “Advanced Query Tuning in MySQL 5.6 and 5.7” (my slides and a replay available here). As promised here is the list of questions and my answers …

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Getting EXPLAIN information from already running queries in MySQL 5.7

When a new version of MySQL is about to be released we read a lot of blog posts about the performance and scalability improvements. That’s good but sometimes we miss some small features that can …

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Speed up GROUP BY queries with subselects in MySQL

We usually try to avoid subselects because sometimes they force the use of a temporary table and limits the use of indexes. But, when is good to use a subselect? This example was tested over …

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MySQL 5.7 key features

The other day I was discussing new features of MySQL 5.7 with a Percona Support customer. After that conversation, I thought it would be a good idea to compile list of important features of MySQL …

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MySQL indexing 101: a challenging single-table query

We discussed in an earlier post how to design indexes for many types of queries using a single table. Here is a real-world example of the challenges you will face when trying to optimize queries: …

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How small changes impact complex systems – MySQL example

If you’ve been studying complex systems you know what minor changes might cause consequences of much greater proportions, sometimes causing some effects that are not easily explained at first. I recently ran across a great …

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MySQL and OpenStack deep dive: Dec. 10 webinar

Fact: MySQL is the most commonly used database in OpenStack deployments. Of course that includes a number of MySQL variants – standard MySQL by Oracle, MariaDB, Percona Server, MySQL Galera, Percona XtraDB Cluster, etc. However, …

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MySQL & OpenStack: How to overcome issues as your dataset grows

MySQL is the database of choice for most OpenStack components (Ceilometer is a notable exception). If you start with a small deployment, it will probably run like a charm. But as soon as the dataset …

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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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