Sync MySQL Servers with ProxySQL Cluster

In the two previous blog posts about ProxySQL Cluster we described how to setup a Cluster, how to add users/rules and propagate them across the Cluster, how to provision new nodes, how to re-sync nodes after they have been out of the Cluster, and some features in the roadmap, especially around the concept of core nodes vs satellite nodes.
We also mention that there are 4 modules/tables that currently ProxySQL Cluster is able to sync:

• mysql_query_rules
• mysql_servers
• mysql_users
• proxysql_servers

We covered 3 of these, and the last one missing is how to sync mysql_servers, related to MySQL …

Notes/errata/updates for Chapter 3:
See the official book errata at http://tahaghoghi.com/LearningMySQL/errata.php – Chapter 3 includes pages 95 – 106.

On p. 96 – 97, there is an example of what you will see with SHOW DATABASES; You will likely also see sys, INFORMATION_SCHEMA and PERFORMANCE_SCHEMA databases.

On p. 97, it says “There are some restrictions on what characters and words you can use in your database, table and other names.” These days, it is possible to escape characters and reserved words, but it is still not recommended.

On p. 101-102, there are examples of how to run the MySQL monitor in “batch mode”. It says you can use either “SOURCE” or the redirection operator on commandline (

As continue of the previous blog posted on Aug 17, 2017, please find below a list conferences & events where you can find MySQL Community team or MySQL experts during the period of second half of September till end of December. The ones which are new are marked below. Please be aware that the list does not have to be final and during the time more events could be added or some of them removed. 

NA&LAD

• Madison PHP, Madison, US, Sep 22-23, 2017​

  • MySQL Community team is supporting this PHP conference as Community partner.
• Oracle Open …

A MySQL replication topology can be very complex (never underestimate a DBA’s creativity). But it’s very frequent to use an asynchronous slave from your primary database to run reporting or logical backup… or any kind of read workload you need. It can also be used as delay slave for data restore purpose.

Once you decided to provide HA to your primary database by migrating to MySQL InnoDB Cluster, you can of course still need and use one or more asynchronous slaves.

You have then an architecture that looks like this :

So as you can notice, your asynchronous slave needs to pick one of the members of the cluster as master. However when this node that act as master crashes (or is stopped for maintenance) what’s happening ?

…

Hello again! On August 16, we delivered a webinar on MySQL backups. As always, we’ve had a number of interesting questions. Some of them we’ve answered on the webinar, but we’d like to share some of them here in writing.

What is the best way to maintain daily full backups, but selective restores omitting certain archive tables?

There are several ways this can be done, listed below (though not necessarily limited to the following):

1. Using logical dumps (i.e., mydumper, mysqlpump, mysqldump). This allows you to dump per table and thus be able to selectively restore.
2. Backup the important tables and archive tables separately, allowing to restore separately as well. This is a better …

Welcome to another post in our series of interview blogs for the upcoming Percona Live Europe 2017 in Dublin. This series highlights a number of talks that will be at the conference and gives a short preview of what attendees can expect to learn from the presenter.

This blog post is with Bernd Erk, CEO of Icinga. His talk is titled Monitoring Open Source Databases with Icinga. Icinga is a popular open source successor of Nagios that checks hosts and services, and notifies you of their statuses. But you also need metrics for performance and growth to deal with your scaling needs. Adding conditional behaviors …

I published a new CTE blog here.

Welcome to another post in our series of interview blogs for the upcoming Percona Live Europe 2017 in Dublin. This series highlights a number of talks that will be at the conference and gives a short preview of what attendees can expect to learn from the presenter.

This blog post is with Daniel Lee, a software developer at Grafana. His tutorial is Visualize Your Data With Grafana. This presentation teaches you how to create dashboards and graphs in Grafana and how to use them to gain insight into the behavior of your systems. In our conversation, we discussed how data visualization could benefit your database …

In this blog, I’ll look at how to use ClickHouse for parallel log processing.

Percona is seen primarily for our expertise in MySQL and MongoDB (at this time), but neither is quite suitable to perform heavy analytical workloads. There is a need to analyze data sets, and a very popular task is crunching log files. Below I’ll show how ClickHouse can be used to efficiently perform this task. ClickHouse is attractive because it has multi-core parallel query processing, and it can even execute a single query using multiple CPUs in the background.

I am going to check how ClickHouse utilizes multiple CPU cores and threads. I will use a server with two sockets, equipped with “Intel(R) Xeon(R) CPU E5-2683 v3 @ 2.00GHz” in each. That gives a total of 28 CPU cores / 56 CPU threads.

To analyze workload, I’ll use an Apache log file from one of Percona’s servers. …

In this post, we will discuss how to search code with the help of cscope. Let’s begin by checking its description and capabilities (quoting directly from http://cscope.sourceforge.net/):

Cscope is a developer’s tool for browsing source code.

• Allows searching code for:
  • all references to a symbol
  • global definitions
  • functions called by a function
  • functions calling a function
  • text string
  • regular expression pattern
  • a file
  • files including a file
• Curses based (text screen)
• An …