Our pleasure to remind everyone about three events which are happening this week and MySQL is part of. Please find them below.

• PerconaLive, Austin, TX, US, May 28-30, 2019

  • as we previously announced MySQL is Silver sponsor w/ booth and several MySQL related talks as follows:
    • Tuesday, May 28, 2019:
      • MySQL Tutorial on: "MySQL InnoDB Cluster in a Nutshell: The Saga Continues with 8.0, the full guide" by Frederic Descamps & Kenny Gryp. Time: 9:30-12:30pm.
    • Wednesday, May 29:
      • 11:00-11:50, Room: Hill Country A: "Complex Stateful Applications Made Easier with Kubernetes" by Patrick Galbraith, the Principal Member of MySQL …

This is a CRITICAL update and the fix mitigates the issues described in CVE-2019-12301. If you upgraded packages on Debian/Ubuntu to 5.6.44-85.0-1, please upgrade to 5.6.44-85.0-2 or later and reset all MySQL root passwords.

Issue

On 2019-05-18 Percona discovered an issue with the Debian/Ubuntu 5.6.44-85.0-1 packages for Percona Server for MySQL. When the previous versions, upgraded to the new version PS 5.6.44-85.0-1 on deb based systems, the MySQL root password was removed allowing users to login to the upgraded server as MySQL root without specifying a password.

Scope

This issue is limited to users who upgraded with the Debian/Ubuntu package 5.6.44-85.0-1 for Percona Server for MySQL v. 5.6. Newer versions (v. 5.7 and above) and new …

Database migrations don’t scale well. Typically you need to perform a great deal of tests before you can pull the trigger and switch from old to new. Migrations are usually done manually, as most of the process does not lend itself to automation. But that doesn’t mean there is no room for automation in the migration process. Imagine setting up a number of nodes with new software, provisioning them with data and configuring replication between old and new environments by hand. This takes days. Automation can be very useful when setting up a new environment and provisioning it with data. In this blog post, we will take a look at a very simple migration - from standalone Percona Server 5.7 to a 3-node Percona XtraDB Cluster 5.7. We will use Ansible to accomplish that.

Environment Description

First of all, one important disclaimer - what we are going to show here is only a draft of what you might like to run in production. It does …

I recently stumbled upon a very interesting post by Lukas Eder, where he describes 10 query transformations which do not depend on the database’s cost model. He posted it a couple of years ago, though when I read it, I assumed some portions of it may still be relevant today.

In the original post, several databases were tested to see if their internal optimizer will be able to automatically re-write the SQL queries and optimize them. In those tests, MySQL under-performed in several of the use cases (the tested version was MySQL 8.0.2, which was released on 2017-07-17).

Seeing those results, and given the previous evaluation was done almost two years ago, I thought that now can be a good chance to re-evaluate a few of those tests with the latest MySQL 8.0.16 (released on 2019-04-25), and demonstrate …

In this blog, we will see how to do a flashback recovery or rolling back the data in MariaDB, MySQL and Percona.

As we know the saying  “All humans make mistakes”, following that in Database environment the data modified accidentally can bring havoc to any organisations.

Recover the lost data

• The data can be recovered from the latest full backup or incremental backup when data size is huge it could take hours to restore it.
• From backup of Binlogs.
• Data can also be recovered from delayed slaves, this case would be helpful when the mistake is found immediately, within the period of delay.

We can use anyone of the above ways or other that can help to recover the lost data, but what really matters is, What is the …

errno: 24 - Too many open files
You might see this error inside MySQL's error log file or during mysql_upgrade operation.

Can't open file: ‘./db/table.frm' (errno: 24 - Too many open files)
To solve this issue, you will need to change the open files limit at system and db service level.

--> To check and change this limit at the system level, we use ulimit client tool to set it dynamically.

* Check current system open file limit.
root@test:~# ulimit -a core file size          (blocks, -c) 0 data seg …

At MariaDB Foundation, we are proud of MariaDB Server getting plenty of contributions. But we don’t want to get cocky, so here is an update about where we stand, and what we want to make happen. First, we have shown our contribution pride in several places. On 15 February 2019, I tweeted On code contributions, […]

The post On Contributions, Pride and Cockiness appeared first on MariaDB.org.

As continue of our previous announcement from March 14, please find below a list of shows & conferences where you can find MySQL team at:

• June 2019:

  • OpenSource Conference, Hokkaido, Japan, May 31-June 1, 2019

    • As we already announced MySQL is a Gold sponsor of this OS show. Our MySQL local team is going to staff the MySQL booth in the expo area as well having a MySQL talks as follows:
      • "MySQL Update + MySQL InnoDB Cluster" given by Daisuke Inagaki, the MySQL Principal Solutions Engineer. His talk is being hold on May 31 @13:55.
      …

Monitoring MySQL server has never been an easy task. Monitoring also needs to go through many Complex and difficult queries to get the details.

All these problems can be overcome by an excellent command line monitoring tool  called “Innotop”. Innotop comes with many features and different types of modes/options, which helps to monitor different aspects of MySQL  (InnoDB) performance and also helps database administrator to find out what’s wrong going with MySQL server. Innotop helps in monitoring user statistics, mysql replication status,query list, InnoDB I/O informations etc. Another important thing about innotop is it refreshes the data continuously , so we can view realtime statistics.

Innotop is one of the designed based on top utility for linux.

Recently, I was working on one of the support ticket where customer was complaining that when he change datadir location by copying datadir from C: to F:, set mysql permissions and changing location in my.ini, he could not able to start mysql. Even no error msg in MySQL error log OR application log that why it doesn’t start.

We have checked all the required steps mentioned in documentations and blog posts but still the issue was not getting resolved. Finally, one of my colleague suggested to read this forum post.

https://forums.mysql.com/read.php?169,659235,659254#msg-659254

and we found out that NETWORK SERVICE permission is required for datadir. By default, it will be given to the C:\ but not for other drives. So when we change any datadir to other drive like E:\ or F:\, we …