MySQL

Percona Server 5.7.10-1 first RC available

Percona is glad to announce the first release candidate of Percona Server 5.7.10-1 on December 14, 2015. Download the latest version from the Percona web site or from the Percona Software Repositories.
This release contains all the bug fixes from latest Percona Server 5.6 release (currently Percona Server 5.6.27-76.0).
New Features:

Percona Server 5.7.10-1 is not available on RHEL 5 […]

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rows_examined_per_scan, rows_produced_per_join: EXPLAIN FORMAT=JSON answers on question “What number of filtered rows mean?”

At the end of my talk LinuxPiter conference, a user asked me a question: “What does the EXPLAIN ‘filtered’ field mean, and how do I use it?” I explained that this is the percentage of rows that were actually needed, against the equal or bigger number of resolved rows. While the user was happy with the answer, […]

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attached_condition: How EXPLAIN FORMAT=JSON can spell-check your queries

When you work with complicated queries, especially ones which contain subqueries, it is easy to make a typo or misinterpret column name. While in many cases you will receive a 
column not found error, sometimes you can get strange results instead.
Like finding 4079 countries in Antarctica:

MySQL

mysql> select count(*) from City where CountryCode in (select CountryCode from Country […]

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Percona Server 5.6.27-76.0 is now available

Percona is glad to announce the release of Percona Server 5.6.27-76.0 on December 4, 2015. Download the latest version from the Percona web site or from the Percona Software Repositories.
Based on MySQL 5.6.27, including all the bug fixes in it, Percona Server 5.6.27-76.0 is the current GA release in the Percona Server 5.6 series. Percona Server is open-source […]

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Percona Server 5.5.46-37.6 is now available

Percona is glad to announce the release of Percona Server 5.5.46-37.6 on December 4, 2015. Based on MySQL 5.5.46, including all the bug fixes in it, Percona Server 5.5.46-37.6 is now the current stable release in the 5.5 series.
Percona Server is open-source and free. Details of the release can be found in the 5.5.46-37.6 […]

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