Search Results for: index lock

Multiple column index vs multiple indexes

(There is an updated version of the content in this post by Percona’s Stephane Combaudon available here.) After my previous post there were questions raised about Index Merge on Multiple Indexes vs Two Column Index efficiency. I mentioned in most cases when query can use both of the ways using multiple column index would be […]

Looking deeper into InnoDB’s problem with many row versions

A few days ago I wrote about MySQL performance implications of InnoDB isolation modes and I touched briefly upon the bizarre performance regression I found with InnoDB handling a large amount of versions for a single row. Today I wanted to look a bit deeper into the problem, which I also filed as a bug. First […]

Looking for InnoDB/XtraDB hacker

We are happy to see that Percona Server/XtraDB and XtraBackup are raising popularity and to keep excitement we want to have more features and more performance fixes! If you are experienced software engineer and feel strong enough to hack InnoDB/XtraDB code we invite you to join our development team to work on the following (but […]

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 5.7. The latest MySQL 5.7.6 release candidate (RC) is out and is packed with nice features. Here’s a list of […]

Optimizer hints in MySQL 5.7.7 – The missed manual

In version MySQL 5.7.7 Oracle presented a new promising feature: optimizer hints. However it did not publish any documentation about the hints. The only note which I found in the user manual about the hints is: It is now possible to provide hints to the optimizer by including /*+ … */ comments following the SELECT, […]

Generated (Virtual) Columns in MySQL 5.7 (labs)

About 2 weeks ago Oracle published the MySQL 5.7.7-labs-json version which includes a very interesting feature called “Generated columns” (also know as Virtual or Computed columns). MariaDB has a similar feature as well: Virtual (Computed) Columns. The idea is very simple: if we store a column

in our table we may want to filter or group […]

Deep dive into MySQL’s innochecksum tool

One of our Percona Support customers recently reported that Percona XtraBackup failed with a page corruption error on an InnoDB table. The customer thought it was a problem or bug in the Percona XtraBackup tool. After investigation we found that an InnoDB page was actually corrupted and a Percona XtraBackup tool caught the error as […]

Percona XtraDB Cluster 5.6.22-25.8 is now available

Percona is glad to announce the new release of Percona XtraDB Cluster 5.6 on March 5th 2015. Binaries are available from downloads area or from our software repositories. Based on Percona Server 5.6.22-72.0 including all the bug fixes in it, Galera Replicator 3.9, and on Codership wsrep API 25.8, Percona XtraDB Cluster 5.6.22-25.8 is now […]