A few days ago, I stepped into a trap !  This made me lose time for fixing things (and even more for writing this post...).  In the hope that you will avoid my mistake, I am sharing this war story.  I also obviously opened a bug, more about this below.

TL&DR: be careful when using CHANGE MASTER TO MASTER_DELAY = N: it might wipe your relay logs !

As written in the TL&DR, running CHANGE MASTER 

We know that MySQL query cache is deprecated as of MySQL 5.7.20 and removed in MySQL 8.0 and It has been recommended to use ProxySQL (or other) external query cache instead.

In this blog post, we’ll present the ProxySQL query cache functionality and how does it help us.

How to setup ProxySQL between client and database servers is out of the scope of this article.

If you are looking for other articles on ProxySQL Series :

• MySQL replication Read-Write Split up
• Replication Switchover using Proxysql And …

Releasing Excellent Strategies to Begin a University or college Essay Make certain your strategy includes a launch, mid and bottom line. In accordance with the system which you will need to obtain, there exist unique problems on how to write a effect cardstock to a documentary you should make. In the carry on piece, you may also check the documentary with other individuals around the specified variety or issue so that you can get paid audience have greater understanding of the report. Your visitor would desire to know just how the making has effects on them-and regardless of if the studying will at the mercy of them most definitely Correct right away, it is best to painting a photograph within the particular person or scenario and display the activity transpiring. Evidently, it’s not possible to obtain all the deserving thoughts with the txt in 20 min, but which can be the length of time it entails to build your appearance and select even if you …

Aiven Blog: Read about the 2019 launch of Aiven for MySQL, a popular database engine for better handling of back-ups in cloud environments.

MySQL is the next database engine to be launched on Aiven.

Since 5.7.12 MySQL includes what is called the X plugin, but also it includes X protocol and X DevApi. But what is all this and how does it work? Let me share a personal short story on how I found myself investigating this feature. In a previous post I wrote about the MySQL Router tool, and our colleague Mr. Lefred pointed out that I was wrong about X protocol, because I mentioned it was created to be used with JSON docs. Given this input, I wanted to investigate in a little bit more depth about what all this “X” means and how it can be used in our day to day operations.

First problem I found is that the documentation is pretty extensive in the how’s but it was really hard to find the what’s. This is a bit strange, because for people trying to research about …

The MariaDB Foundation is pleased to announce the availability of MariaDB 10.3.12, the latest stable release in the MariaDB 10.3 series, as well as MariaDB Connector/ODBC 3.0.8, the latest stable release in the MariaDB Connector/ODBC series. See the release notes and changelogs for details. Download MariaDB 10.3.12 Release Notes Changelog What is MariaDB 10.3? MariaDB […]

The post MariaDB 10.3.12 and MariaDB Connector/C 3.0.8 now available appeared first on MariaDB.org.

1.0. Introduction:

MySQL 8.0 was released with awesome features. One of its most prominent features is CTE (Common Table Expression).

The Common Table Expression can be used to construct complex queries in a more readable manner. In this blog, I have described how the CTE works with some useful examples.

1.1 What is CTE?

A Common Table Expression (CTE) is the result set of the query, which exists temporarily and uses only within the context of a larger query.

The CTE provides better readability and performance in comparison with a derived table.

In a normal query the temporary result set that exists only within the execution scope of a single SQL statement.

Example:

select …

As you know, MySQL uses some keywords and some of them are also reserved.

Let’s have a look how to deal with that:

mysql> create table WRITE (id int auto_increment primary key, varying varchar(10), than int);
 ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your 
MySQL server version for the right syntax to use near 'WRITE (id int auto_increment primary key, 
varying varchar(10), than int)' at line 1

OK, it seems WRITE is a keyword I cannot use as table name. I’ve then two choices:

• rename the table to something else like WRITE_TBL
• use back-ticks (`) around the table like `WRITE`

Let’s use the first option:

mysql> create table WRITE_TBL (id int auto_increment primary key, varying varchar(10), than …

MySQL is extensive and has lots of areas to optimize and tweak for the desired performance. Some changes can be performed dynamically, others require a server restart. It is pretty common to find a MySQL installation with a default configuration, although the latter may not be appropriate per se from your workload and setup.

Here are the key areas in MySQL which I have taken from different expert sources in the MySQL world, as well as our own experiences here at Severalnines. This blog would serve as your cheat sheet to tune performance and make your MySQL great again :-)

Let’s take a look on these by outlining the key areas in …