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Django with time zone support and MySQL

This is yet another story of Django web-framework with time zone support and pain dealing with python datetimes and MySQL on the backend. In other words, offset-naive vs offset-aware datetimes. Shortly, more about the problem. …

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How a set of queries can be killed in MySQL using Percona Toolkit’s pt-kill

You might have encountered situations where you had to kill some specific select queries that were running for long periods and choking the database. This post will go into more detail with an example of report …

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High Availability with mysqlnd_ms on Percona XtraDB Cluster

This is the second part of my series on High Availability with mysqlnd_ms. In my first post, “Simple MySQL Master HA with mysqlnd_ms,” I showed a simple HA solution using asynchronous MySQL replication. This time we …

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Database auditing alternatives for MySQL

Database auditing is the monitoring of selected actions of database users. It doesn’t protect the database in case privileges are set incorrectly, but it can help the administrator detect mistakes. Audits are needed for security. …

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Using Apache Hadoop and Impala together with MySQL for data analysis

Apache Hadoop is commonly used for data analysis. It is fast for data loads and scalable. In a previous post I showed how to integrate MySQL with Hadoop. In this post I will show how …

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Creating GEO-enabled applications with MySQL 5.6

In my previous post I’ve showed some new MySQL 5.6 features which can be very helpful when creating geo-enabled applications. In this post I will show how we can obtain open-source GIS data, convert it to …

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How to log slow queries on Slave in MySQL 5.0 with pt-query-digest

Working as a Percona Support Engineer, every day we are seeing lots of issues related to MySQL replication. One very common issue is slave lagging. There are many reasons for slave lag but one common reason …

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Tools and tips for analysis of MySQL’s Slow Query Log

MySQL has a nice feature, slow query log, which allows you to log all queries that exceed a predefined about of time to execute. Peter Zaitsev first wrote about this back in 2006 – there …

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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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Using the new spatial functions in MySQL 5.6 for geo-enabled applications

Geo-enabled (or location enabled) applications are very common nowadays and many of them use MySQL. The common tasks for such applications are: Find all points of interests (i.e. coffee shops) around (i.e. a 10 mile …

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