Prior to my talk at LaraconEU 2016 I was curious to know how much adoption for MySQL 5.7 was in within the community.

I tweeted this:

Pool, use twitter client to see it:

Which Version of MySQL do you use? SELECT @VERSION; RT for reach, please.

—
Gabriela D'Ávila (@gabidavila) August 23, 2016

Twitter polls only gives you up to 4 items to choose. What I wanted to know is if people were using MariaDB or other forks like Percona, but I didn’t had the proper space, and I  only put three options.

This January I managed to get a bit more syndication on my tweet and more people replied. I added a 4th option, “Other”. This option could …

In this blog post, I’ll look at the types of NVMe flash health information you can get from using the NVMe command line tools.

Checking SATA-based drive health is easy. Whether it’s an SSD or older spinning drive, you can use the

smartctl

 command to get a wealth of information about the device’s performance and health. As an example:

root@blinky:/var/lib/mysql# smartctl -A /dev/sda
smartctl 6.5 2016-01-24 r4214 [x86_64-linux-4.4.0-62-generic] (local build)
Copyright (C) 2002-16, Bruce Allen, Christian Franke, www.smartmontools.org
=== START OF READ SMART DATA SECTION ===
SMART Attributes Data Structure revision number: 16
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
 1 Raw_Read_Error_Rate     0x002f   100   100   000 …

I was working on a seemingly basic query the other day where the user needed to have an INT column listed in ascending order (i.e., 1, 2, 3, …).

However, the tricky part came in because the column allowed NULLs and the user needed the NULLs to be listed last, not first, which is the default behavior in both MariaDB and MySQL.

We first devised a somewhat convoluted solution where we used ISNULL() first in the ORDER BY, and then the column, but that wasn’t ideal since it added an additional check for each row in the ORDER BY, which we wanted to avoid in a query returning ~5M rows.

To illustrate, a normal query just sorting in ASC order returned:

MariaDB> SELECT * FROM t1 ORDER BY col1 ASC, col3 ASC;
+--------+--------+------+
| col1   | col2   | col3 |
+--------+--------+------+
| apple  | yellow | NULL |
| apple  | red    |    5 |
| apple  | green  |   10 |
| banana | brown  | NULL |
| banana | green  |    5 |
| …

Introduction As previously explained, you can run database integration tests 20 times faster! The trick is to map the data directory in memory, and my previous article showed you what changes you need to do when you have a PostgreSQL or MySQL instance on your machine. In this post, I’m going to expand the original … Continue reading How to run integration tests at warp speed using Docker and tmpfs →

Percona announces the release of Percona Server 5.6.35-80.0 on February 8, 2017. Download the latest version from the Percona web site or the Percona Software Repositories.

Based on MySQL 5.6.35, and including all the bug fixes in it, Percona Server 5.6.35-80.0 is the current GA release in the Percona Server 5.6 series. Percona Server is open-source and free – this is the latest release of our …

As a part database administration, DBA has to take care of sub-components of database like server logs and has to plan for maintenance activity for these components regularly.

MySQL has various types of log i.e binary log, error log, slow query log, general log for different purposes. And after certain time these logs will grow and you will start seeing issues like low disk space, a large number of logs etc.

MySQL allows you to flush logs using flush logs command, next “How to rotate and clean up old MySQL logs? ”

Linux has a utility called “logrotate” , using logrotate we can implement log rotation for MySQL server logs.

Binary logs: This one is critical if you have replication setup, By enabling  expire_logs_days mysql variable you can manage …

This blog we describe an issue with MySQL 5.7’s super_read_only feature when used alongside with GTID in chained slave instances.

Background

In MySQL 5.7.5 and onward introduced the gtid_executed table in the MySQL database to store every GTID. This allows slave instances to use the GTID feature regardless whether the binlog option is set or not. Here is an example of the rows in the gtid_executed table:

mysql> SELECT * FROM mysql.gtid_executed;
+--------------------------------------+----------------+--------------+
| source_uuid                          | interval_start | interval_end | …

There are several advantages to keeping up to date with the latest major versions of MySQL. To provide a short example using MySQL 5.7:

• Let application developers benefit from new functionality, e.g. JSON in 5.7
• Use your hardware infrastructure more efficiently with parallel slaves in 5.7
• Improve monitoring or management for DevOps with more performance schema instrumentation in 5.7
• Improve security by using features like  transparent data encryption, firewall, auditing, and sha256 authentication in 5.7
• Keep within the EOL window for access to maintenance releases and support

This blog post explains general activities in an upgrade project and what to look out for prior to an upgrade between major MySQL Server releases.…

MySQL 5.7 introduced the LOGICAL_CLOCK type of multi-threaded slave (MTS).  When using this type of parallel replication (and when slave_parallel_workers is greater than zero), slaves use information from the binary logs (written by the master) to run transactions in parallel.  However, enabling parallel replication on slaves might not be enough to get a higher replication throughput (VividCortex

The MySQL developer tools team announces 6.3.9 as our GA release for MySQL Workbench 6.3.

For the full list of changes in this revision, visit
http://dev.mysql.com/doc/relnotes/workbench/en/changes-6-3.html

For discussion, join the MySQL Workbench Forums:
http://forums.mysql.com/index.php?152

Download MySQL Workbench 6.3.9 GA now, for Windows, Mac OS X 10.10+,
Oracle Linux 7, Fedora 24 and 25, Ubuntu 16.04 and 16.10 or sources, from:

http://dev.mysql.com/downloads/tools/workbench/

Enjoy!