With MySQL 8.0, engineers improved the visibility of data locking. Usually it was not that easy to deal with the output of SHOW ENGINE INNODB STATUS and mixing Information_Schema tables like INNODB_LOCKS and INNODB_LOCK_WAITS.

So in MySQL 8.0 we instrument data locks in Performance_Schema and we changed the SYS Schema view related to the InnoDB Locks Wait too.

This means that when a transaction A is locking row R, and transaction B is waiting on this very same row, B is effectively blocked by A. What we added is extra instrumentation to expose which data is locked (R), who owns the lock (A), and who is waiting for the data (B).

Testing

Let’s have a look at this simple scenario in MySQL 5.7.21 and 8.0.4 to compare:

2 clients starting a …

Some regulations required that the password is renewed in a timely and appropriate manner (e.g. every 90 days). In this article, 2nd of the MySQL 5.7 Security series, we will see how to to establish a policy for password expiration with MySQL 5.7 Password Management.

Security is one of the hottest topics lately, and in this blog post, I will walk you through what needs to be configured to have a working three-node Percona XtraDB Cluster running with InnoDB Tablespace Encryption enabled.

This article will not cover the basics of setting up a cluster nor will it cover how to create SSL certs and keys since both of these topics have been well explained here and here.

Just to give you a brief history, InnoDB tablespace encryption was introduced in MySQL 5.7.11, and starting from …

For many programming languages, it's pretty easy to figure out which Connector to use. Java has Connector/J, if you're using C# or ASP you'll opt for Connector/.NET: the clue is in the name.

For PHP however, things aren't quite so straightforward. If you want to write a PHP application that communicates with a MySQL database, you have a choice of PHP extensions that you can use: mysql, mysqli, and PDO_MySQL.

We can simplify that list right away by discounting the mysql extension. This is old and was intended for use with MySQL versions before 4.1. It does not support many of the things that you can take for granted with the other two, such as improved MySQL authentication protocols or the ability to create prepared statements to prevent against SQL injection. It was dropped from PHP 7. In fact, you would have to jump through a couple of hoops just to get it to work with a later version of MySQL. So don't bother!

The mysql …

Percona announces the release of Percona Monitoring and Management 1.8.1. PMM (Percona Monitoring and Management) is a free and open-source platform for managing and monitoring MySQL and MongoDB performance. You can run PMM in your own environment for maximum security and reliability. It provides thorough time-based analysis for MySQL and MongoDB servers to ensure that your data works as efficiently as possible.

This release contains bug fixes only and supersedes Percona Monitoring and Management 1.8.0.

Improvements

• PMM-2051: The ProxySQL Overview dashboard enables selecting more than one host group in the Hostgroup field.
• PMM-2163: Dashboards based on the …

Please join Percona Technical Account Manager Tim Sharp, as he presents How Percona Maintains Optimal Customer Health on Thursday, March 8, 2018 at 11:00 am PST (UTC -8) / 2:00 pm EST (UTC -5).

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How do you guarantee optimal database performance for your critical applications and services? Proactive monitoring and intervention is one way.

Percona Technical Account Managers (TAM) are expert DBAs that provide proactive assistance to our Managed Service customers – helping to guarantee performance, …

Changes as compared to Monyog MySQL Monitor v8.4.1 include:

This release fixes a few minor bugs only and implements a number of user requests.

Features:

• Monyog can now analyze MariaDB and MySQL enterprise Audit log.
• Added support for LDAP with StartTLS and SSL.
• The default path for MONyog.log can be changed using the parameter “MONyogLogPath” from the MONyog.ini file.

Bug Fixes:

• Monyog logged bogus SQLite errors on fresh installation.
• Monyog displayed console error if LDAP group name contained inverted comma.
• Changed alert condition for “Seconds behind master” monitor to consider “NULL” as an alertable condition. It considered the value “NULL” stable condition earlier.
• On upgrading, Monyog filled the mail alert field for sniffer with the bogus email id “admin@mydomain.com”.
• On selecting a …

As you may already know, MySQL 8.0 is coming with SQL Roles . I’ve already quoted them before in some posts (here and here). Giuseppe Maxia is doing a great job testing and promoting them (thank you for that!). Of course he also made some remarks on …

Prior to MySQL 8.0, MySQL was missing a very well know feature in other RDBMS: optimizer histograms.

The Optimizer Team implemented this feature as more and more MySQL DBAs were requesting it.

Definition

But what are histograms ? For wikipedia, a histogram is an accurate representation of the distribution of numerical data. For RDBMS, a histogram is an approximation of the data distribution within a specific column.

So in MySQL, histograms help the optimizer to find the most efficient Query Plan.

Example

To illustrate how histograms  influence the optimizer, I will use data from dbt3.

My query is simple: …

In this post I’ll look at some of our recent work for benchmark enthusiasts: a TPCC-like workload for Sysbench (version 1.0 or later).

Despite being 25 years old, the TPC-C benchmark can still provide an interesting intensive workload for a database in my opinion. It runs multi-statement transactions and is write-heavy. We also decided to use Sysbench 1.0, which allows much more flexible LUA scripting that allows us to implement TPCC-like workload.

For a long time, we used the tpcc-mysql (https://github.com/Percona-Lab/tpcc-mysql) tool for performance evaluations of MySQL and Percona Server for MySQL, but we recognize that the tool is far from being intuitive and simple to use. So we hope the adaptation for Sysbench will …