Thank you to everyone who joined us for the 19th edition of MyWebinar. We hope that our time together helped to elevate and seam your work to perfection. We’re committed to giving back to the opensource database community in the coming days by presenting more LIVE events.

Recently, Mydbops conducted a webinar on the top 10 features of MySQL 8. MySQL is one of the most popular and widely used open-source relational database management systems. With every new version, MySQL brings new features and enhancements that make it more reliable, secure, and efficient. In this blog, we will wrap up the top 10 features of MySQL 8 discussed in the webinar by Mydbops.

Vinoth Kanna, co-Founder from  …

Percona XtraBackup is an open source hot backup utility for MySQL-based servers. To take consistent and hot backup, it uses various locking methods, especially for non-transactional storage engine tables. This blog post discusses the cause and possible solution for queries with ​Waiting for table flush state in processlist when taking backups using Percona XtraBackup. Only MySQL 5.7 version is affected by this, as per my tests.

Type of locks taken by Percona XtraBackup

Before discussing the main issue, let’s learn about the type of locks used by Percona XtraBackup to take consistent backups. Percona XtraBackup uses backup locks as a lightweight alternative to FLUSH TABLES WITH READ LOCK. This feature is …

I discovered a dependency for MySQL Workbench on AlmaLinux 8 installation. I neglected to fully cover it when I documented the installation in a VM of AlmaLinux 9. I go back later and update that entry but for now you need the following dependencies:

proj-6.3.2-4.el8.x86_64.rpm
proj-datumgrid-1.8-6.3.2.4.el8.noarch.rpm
proj-devel-6.3.2-4.el8.x86_64.rpm

Install like this:

sudo dnf install -y *.rpm

Log file:

Last metadata expiration check: 3:01:53 ago on Fri 10 Feb 2023 03:37:49 AM UTC.
Dependencies resolved.
==========================================================================================
 Package                Architecture   Version                 Repository            Size
==========================================================================================
Installing:
 proj                   x86_64         6.3.2-4.el8             @commandline         2.0 M
 proj-datumgrid         noarch …

While MySQL error codes are useful, understanding what they mean can be difficult. This article looks at common MySQL error codes, non-coded errors, and how to fix them.

MySQL error code format

Each MySQL error includes:

• An error number: A MySQL-specific number corresponding to a particular error.
• An SQLSTATE value: A five-character string that indicates the error condition.
• An error message: A textual description of the error.

MySQL error example

Here’s an example of what a MySQL error code looks like:

ERROR 1146 (42S02): Table 'test.no_such_table' doesn't exist

In the error above:

The latest MySQL release has been published on January 17th, 2023. MySQL 8.0.32 contains some new features and bug fixes. As usual, it also contains contributions from our great MySQL Community.

I would like to thank all contributors on behalf of the entire Oracle MySQL team !

MySQL 8.0.32 contains patches from Facebook/Meta, Alexander Reinert, Luke Weber, Vilnis Termanis, Naoki Someya, Maxim Masiutin, Casa Zhang from Tencent, Jared Lundell, Zhe Huang, Rahul Malik from Percona, Andrey Turbanov, Dimitry Kudryavtsev, Marcelo Altmann from Percona, Sander van de Graaf, Kamil Holubicki from Percona, Laurynas Biveinis, Seongman Yang, Yamasaki Tadashi, Octavio Valle, Zhao Rong, Henning Pöttker, Gabrielle Gervasi and Nico Pay.

Here is the …

A couple of days ago I was creating an index on the source and when I checked the replica side it was not replicated, so I just wanted to explain how the replication filter may increase the complexity of your DBA operations.

Replication occurs by reading events from the binary log of the source and then executing them on the replica. The events in the binary log are recorded in different formats, depending on the type of event. These formats are determined by the binary logging format used when the events were initially recorded on the source. The relationship between the binary logging formats and the terminology used during replication is as follows:

When using statement-based binary logging, the source writes SQL statements to the binary log. Replication of the source to the replica is performed by executing these SQL statements on the replica. This is known as statement-based replication (SBR), and it …

- Read Replicas with Load Balancer
- Replication Filters
- Replication Sources Without GTIDs
- MySQL HeatWave for AWS

This presentation is just a summary of new features in MySQL HeatWave.

For a more thorough and exhaustive view please read the following:

- https://docs.oracle.com/en-us/iaas/releasenotes/services/mysql-database/

- https://dev.mysql.com/doc/relnotes/heatwave/en/

The post MySQL HeatWave Report – December 2022 update first appeared on dasini.net - Diary of a MySQL expert.

Recently, while doing a test process to examine resource usage and the time required to alter the table using pt-osc, it leads to a loss of triggers even though the –preserve-triggers option is specified. I made the decision to recreate the identical circumstance so that everyone could see it.

Test environment : 

OS: Amazon Linux 2

MySQL version: 5.7.40

pt-online-schema-change version: 3.1.0

Before digging deeper, we must first obtain the whole picture. Here is an illustration of the table’s structure.

Table structure:

This is an update for MySQL 8 Stored PSM to add the ONLY_FULL_GROUP_BY mode to the global SQL_MODE variable when it’s not set during a session. Here’s the code:

/* Drop procedure conditionally on whether it exists already. */
DROP PROCEDURE IF EXISTS set_full_group_by;

/* Reset delimter to allow semicolons to terminate statements. */
DELIMITER $$

/* Create a procedure to verify and set connection parameter. */
CREATE PROCEDURE set_full_group_by()
  LANGUAGE SQL
  NOT DETERMINISTIC
  SQL SECURITY DEFINER
  COMMENT 'Set connection parameter when not set.'
BEGIN

  /* Check whether full group by is set in the connection and
     if unset, set it in the scope of the connection. */
  IF EXISTS
    (SELECT TRUE
     WHERE NOT REGEXP_LIKE(@@SESSION.SQL_MODE,'ONLY_FULL_GROUP_BY'))
  THEN
    SET @@GLOBAL.SQL_MODE := CONCAT(@@SESSION.sql_mode,',ONLY_FULL_GROUP_BY');
  END IF;
END;
$$

/* Reset the default delimiter. */
DELIMITER ;

You can call the …

This text exists mainly so that I paste the URL into the #mysql channel in Libera IRC.

The mysqldump tools allows you to convert a MySQL database server or individual schemas back to SQL. You are left with a script that is supposed to be loadable into a target server and gives you back the full database, including all objects in it.

You can read that SQL as a script into an empty server to create a new instance, or process it with different tools for different purposes. So in general, a workflow can look like this:

$ mysqldump --options --more-options and parameters > somescript.sql
$ scp somescript.sql somewhere@else.com:
$ ssh somewhere@else.com
...
$ mysql --show-warnings --whatever-options < somescript.sql

Instead of mysql with an input redirect, you may also use the command line client and the source command:

$ mysql …