JKDB PLATFORM – our company’s data management platform

In this post, we introduce backup-restore module,focus on automatic backup and restore in a huge MySQL database environment.

Read this PDF: JKDB:BACKUP-RESTORE

One of the many great new features included in MySQL 5.7 is the generated column. A generated column is a column in a table where the data is calculated for you, based on an expression that you provide.

To understand the benefits of using generated columns, let's consider a very simple example. Imagine that I want to find out how many new hires my organization had in the year 2000. Here's my table:

mysql> DESC employees; +------------+---------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +------------+---------------+------+-----+---------+-------+ | emp_no | int(11) | NO | PRI | NULL | | | birth_date | date | NO | | NULL | | | first_name | varchar(14) | NO | | NULL | | | last_name | varchar(16) | NO | | NULL | | | gender | enum('M','F') | NO | | NULL | | | hire_date | date | NO | | NULL | | +------------+---------------+------+-----+---------+-------+ 6 rows in set (#.## sec)

Percona announces the release of Percona Server for MySQL 5.5.55-38.8 on May 10, 2017. Based on MySQL 5.5.55, including all the bug fixes in it, Percona Server for MySQL 5.5.55-38.8 is now the current stable release in the 5.5 series.

Percona Server for MySQL is open-source and free. You can find release details in the 5.5.55-38.8 milestone on Launchpad. Downloads are available here and from the Percona Software Repositories.

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The first Development Milestone Release (DMR) of MySQL Cluster 7.6--7.6.2--is now available! You can see the full changelog for 7.6.2 here. But before we get into the specifics on 7.6.2, I'd  like to take a minute just to paint the bigger picture of where we want to go with MySQL Cluster over the long term. While we cannot and will not discuss or project version numbers and/or dates for any given feature, it's helpful to know what our bigger goals and longer term roadmap are with MySQL Cluster (see the standard Oracle Safe Harbor disclaimer).

Long Term Goals 

We've set some pretty lofty goals for the …

MySQL Server 5.5.56, new versions of the popular Open Source Database Management System, have been released. These releases are recommended for use on production systems. For an overview of what’s new, please see http://dev.mysql.com/doc/refman/5.5/en/mysql-nutshell.html For information on installing the release on new servers, please see the MySQL installation documentation at http://dev.mysql.com/doc/refman/5.5/en/installing.html These server releases are available in […]

In this post we’ll see how MariaDB’s Handler_icp_% counters status counters (Handler_icp_attempts and Handler_icp_matches) measure ICP-related work done by the server and storage engine layers, and how to see if our queries are getting any gains by using them.

These counters (as seen in SHOW STATUS output) are MariaDB-specific. In a later post, we will see how we can get this information in MySQL and Percona Server. This investigation spun off from comments in Michael’s post about the new MariaDB dashboard in PMM. Comments are very useful, so keep them coming!

We can start by checking the corresponding documentation pages:

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As promised, here is the follow up of the MySQL 8.0-dev Progress teaser ;-)
so, yes, we expect to see the most hot contentions gone, as it's seen from the following graph : Observations :

• the graph is representing the spin waits / spin rounds events happening during the same Sysbench Update-NoKEY workload
• the load is progressing from 8 concurrent users to 16, 32, .. 512
• 3 engines are tested one after one : MySQL 5.7, MySQL 8.0 (current DMR), MySQL 8.0-dev (current prototype)
• first all 3 engines are running on 22cores-HT only (1 CPU socket)
• then, the second time : on 44cores-HT (2 CPU sockets)
• and the most important thing to retain about this graph is that on 8.0-dev we see all main hot contentions gone ;-)

Read more... (4 …

Here are the slides from my talk at Percona Live 2017 conference in Santa Clara, CA.
This has been my first opportunity to speak to a public audience and it has been really great!
Looking forward to speak about MySQL again soon. Thank you!!

In this blog post, I’ll review how a hung MySQL transaction can cause the InnoDB history length to grow and negatively affect MySQL performance.

Recently I was helping a customer discover why SELECT queries were running slower and slower until the server restarts (which got things back to normal). It took some time to get from that symptom to a final diagnosis. Please follow me on the journey of chasing this strange MySQL behavior!

Symptoms

Changes in the query response time can mean tons of things. We can check everything from the query plan to the disk performance. However, fixing it with a restart is less common. After looking at “show engine innodb status”, I noticed some strange lines:

Trx read view will not see trx with id >= 41271309593, sees < 41268384363
---TRANSACTION 41271309586, ACTIVE 766132 sec
2 lock struct(s), heap size 376, 0 row lock(s), undo log entries 1 …

The MySQL Development team announced that the 8.0.1 development milestone release is available for download at dev.mysql.com. (8.0.1 adds features to 8.0.0). The source code is available on GitHub. This release makes several important changes in Unicode character set support. In particular, the default character set has changed from latin1 to utf8mb4. Check out all the changes by reading the