The story of Steven Mapes, an experienced software developer who has been using SQLyog MySQL GUI since 2002.

We were so thrilled to speak with Steven Mapes for two simple reasons. One, he is an ardent user of SQLyog. Two, he has been using the tool since 2002 (we had released the GA version of SQLyog in 2002). And, it is users like Steven who make the product successful with their constant support and feedback that keeps us going.

We go down memory lane and learn some interesting facts about SQLyog that made Steven stick with the tool for more than a decade.

Steven Mapes is a self-employed software solutions provider who develops web-based polyglot solutions for clients often hosted within the cloud since 2012. Before it, he was the Head of IT for Moko Social Media in the UK. When asked about how he came across SQLyog and the need to use the tool, Steven says,”My first exposure to SQLyog was back in 2002 when the …

In this blog post, I’ll look at how ProxySQL Admin behaves in some unusual and unexpected ways from a MySQL perspective.

ProxySQL allows you to connect to its admin interface using the MySQL protocol and use familiar tools, like the MySQL command line client, to manage its configuration as a set of configuration tables. This ability may trick you into thinking that you’re working with a stripped-down MySQL server – and expect it to behave like MySQL. 

It would be a mistake to think this! In fact, ProxySQL embeds the SQLite database to store its configuration. As such, it behaves much closer to SQLite!

Below, I’ll show you a few things that confused me at first. All of these are as of ProxySQL 1.3.6 (in case behavior changes in the future).

Fake support for Use command

On a recent consulting engagement, the PSCE team were charged with what can be considered a fairly common task of synchronising tables between master and slave in MySQL Replication. On this occasion the  schema contained both foreign key constraints and triggers, this post describes how we avoided the potential problems related to such an operation.

The process to synchronise tables in MySQL is to first identify the differences between tables and then execute queries which bring those tables into a consistent state. The first part of the process can be handled by the pt-table-checksum tool, which steps through the table analysing sets of rows (chunks) and recording a checksum value. Then taking advantage of replication, the same process occurs on each of the slaves and the checksums can then be compared. Once the entire table has been processed, a second tool pt-table-sync can be used …

You’ve probably had some troubles with the shared InnoDB tablespace stored in the ibdata file. Especially when it has grown for some reasons and reached a critical size.

This behavior occurs in some cases, due to excessive rollback segments growth or during a migration from a unique shared tablespace to a file-per-table configuration for example.

In this post, I would like to explain how to shrink the ibdata file after an unwanted file growth in a file-per-table configuration.
Note that the process could be done without Trite but the tool avoids to write the script used to transport tables yourself.

Initial situation

Here is a sample of the InnoDB configuration:

innodb_data_file_path = ibdata1:100M:autoextend
innodb_file_per_table

And the status of your datafiles in the datadir directory:

drwx------ 2 mysql mysql 4,0K déc. 20 2012 …

Disclaimer: I’m not specially an expert of benchmarking, this post is to compare different options. All comments and advices are welcome.

I’m not telling you anything new, the show processlist command is a fantastic command line tool for instant check.
But what about monitor your databases with this command embedded in a tool?

Just have a look at this graph:

With 5K queries per seconds, how much will be hidden with a show processlist executed every seconds? Probably a lot.
So, I wanted to test which alternatives could be efficient to retrieve all the queries during a time lapse.

Test procedure and configuration

I used sysbench 0.5 (with oltp.lua) to make my tests on different configurations and …

The goal of this tutorial is to show you how to use Multi-Master and aggregate databases with the same name but with different data from different masters.

Example:

• master1 => a French subsidiary
• master2 => a British subsidiary

Both have the same database (PRODUCTION) but the data are totally different:

We will start with 3 servers (2 masters and 1 slave), you can add more master if needed.

Informations

•  10.10.16.231: first master (aka ”’master1”’) => a French subsidiary
• 10.10.16.232: second master (aka ”’master2”’) => a British subsidiary
• 10.10.16.233: slave (multi-master) (aka ”’slave”’)

If you have already your 3 servers correctly installed go directly to: “Dump your …

Hi,

You can find below the slides of the MySQL Connect 2013, enjoy!
(and much more in the slides page)

I was sincerely affected by this last MySQL post and this other very long post from Jeremy Cole.
Yes, these two guys are MySQL rock stars and they are really impressives, their involvement in the MySQL community is utter!

I don’t want to write a long long speech about my simple life…
I just want to clarify why I do what I do.

Many people have asked or wondered without asking why I do what I do
(Jeremy Cole - 2013)

A few years ago Ashley Unitt asked me what I was most proud of, and now, I can make a complete answer. I’m very proud to take part of a community, MySQL has transformed my job into a passion and an incredible desire to share this passion, as honestly as possible.

What …

A few years ago, I asked to check with me in the long (very long) change history of MySQL 5.5 documentation what are the changes in relation to the SQL syntax.
Chris Calender helped me to retrieve a list of the main changes, thanks again Chris.

Today, I would like to share this list with you.
It is simply a curated transcript of what you might find in the documentation but I’m sure it can help some of you.
 

INTO clause in nested SELECT statements

 
Previously, the parser accepted an INTO clause in nested SELECT statements, which is invalid because such statements must return their results to the outer context. As of MySQL 5.5.3, this syntax is no longer permitted and statements that use it must be changed.
 

Table aliases in DELETE statements

 
In MySQL 5.5.3, several changes …

Did you see this when you are migrating from your lovely MySQL 5.1 to MySQL 5.5?
Oh, sorry, you remain attached to your pretty 4.1. Yes, I know, MyISAM has become so important in your life…

Ok, seriously, I would like to share this little observation I made recently when switching to MySQL 5.5 on one slave.
You can see below two graphs for the transactional activity, there is exactly the same volume of update, delete and insert queries :

MySQL 5.1

MySQL 5.5

But the gray area represents the number of commit per second.
I find that I have much more commit with MySQL 5.5, why? …