Search Results for: partition index

Indexing 101: Optimizing MySQL queries on a single table

I have recently seen several cases when performance for MySQL queries on a single table was terrible. The reason was simple: the wrong indexes were added and so the execution plan was poor. Here are guidelines to help you optimize various kinds of single-table queries. Disclaimer: I will be presenting general guidelines and I do […]

Find unused indexes

I wrote one week ago about how to find duplicate indexes. This time we’ll learn how to find unused indexes to continue improving our schema and the overall performance. There are different possibilites and we’ll explore the two most common here. User Statistics from Percona Server and pt-index-usage. User Statistics User Statistics is an improvement […]

MySQL Partitioning – can save you or kill you

I wanted for a while to write about using MySQL Partitioning for Performance Optimization and I just got a relevant customer case to illustrate it. First you need to understand how partitions work internally. Partitions are on the low level are separate table. This means when you’re doing lookup by partitioned key you will look […]

Sharding and Time Base Partitioning

For large number of online applications once you implemented proper sharding you can consider your scaling problems solved – by getting more and more hardware you can grow. As I recently wrote it however does not mean it is the most optimal way by itself to do things. The “classical” sharding involves partitioning by user_id,site_id […]

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 help us a lot in our day-to-day tasks. One good example is the blog post that Aurimas wrote about a […]

Percona XtraDB Cluster: Quorum and Availability of the cluster

Percona XtraDB Cluster (PXC) has become a popular option to provide high availability for MySQL servers. However many people are still having a hard time understanding what will happen to the cluster when one or several nodes leave the cluster (gracefully or ungracefully). This is what we will clarify in this post. Nodes leaving gracefully […]

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 […]