OTN appreciation day: The Performance Schema of MySQL 5.6+

To focus on just one point for OTN appreciation day on October 11 2016 and to the benefit of all users of MySQL is to consider the extremely convenient and rich value of information available in the MySQL Performance Schema to understand what SQL queries are running in a MySQL instance now. The MySQL Performance Schema in MySQL 5.6 is enabled by default, (performance_schema=on).

The following one off SQL statement will enable the instrumentation of SQL statements in the most detailed level of assessment.

The following query will show you the longest running queries in your database at this present time.

This ease of accessing what is running in a MySQL instance replaces many different and creative techniques as I describe in Improving MySQL Performance with Better Indexes in versions of MySQL before version 5.6.

If your organization does not have dedicated performance experts reviewing new functionality consistently and monitoring your production systems regularly for database optimization, the cost of having the MySQL performance schema available and with a large number of different forms of instrumentation out ways any reason not to.

One of the best presentations at Percona Live Amsterdam last week in the last time slot of the event (before beer and food) was Performance schema and sys schema by Mark Leith . I hope to provide a review of this presentation soon and my interest to explore the new MySQL 5.7 and 8.0 performance schema instruments. A few of my live tweets included:

MySQL 5.7 & 8.0 Performance Schema

Tagged with: MySQL

Producing IQR and Outlier statistics with SQL

The interquartile range (IQR) measures the spread of the middle 50% of a distribution — the distance between the first quartile (Q1) and the third quartile (Q3). Combined with Tukey’s 1.

Producing Mode statistics with SQL

The mode is the value or values that appear most frequently in a dataset. Unlike the mean or median, it applies naturally to categorical and ordinal data — star ratings, product codes, survey responses — and reveals what is most common, not what is average.

Extending MySQL Capabilies with UDFs, Plugins and Components - Part 2

MySQL offers three different approaches to extending the SQL capabilities with the default product you download and install. These are: User Defined Function (UDF) MySQL Manual MySQL Plugin MySQL Manual MySQL Component MySQL Manual In my prior post I provided a new uuidv function that accepted a numeric argument to return a string of the version of UUID specified.