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Webinar Wednesday, January 24, 2018: Differences between MariaDB and MySQL

Join Percona’s Chief Evangelist, Colin Charles as he presents Differences Between MariaDB and MySQL on Wednesday, January 24, 2018, at 7:00 am PDT / 10:00 am EDT (UTC-7).

Register Now

Tags: MariaDB, MySQL, Percona Server for MySQL, DBA, SysAdmin, DevOps
Experience Level: Novice

MariaDB and MySQL. Are they syntactically similar? Where do these two query languages differ? Why would I use one over the other?

MariaDB is on the path of gradually diverging from MySQL. One obvious example is the internal data dictionary …

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Understanding – Group Replication and InnoDB Cluster

In this blog post, I’d like to show some relationships of “Group Replication” and “InnoDB Cluster“.  My hope is that I will be able to draw meaningful correlations and attempt to simplify our way of thinking about these setups. The MySQL development team released the first GA release of Group Replication in MySQL 5.7.17, which turns… Read More »


USE/FORCE/IGNORE INDEX syntax, or index hints, are nice shortcuts to make sure that MySQL will (or will not) use a certain index. But it comes with some drawbacks:

USE/FORCE INDEX will not allow to use an index not mentioned in the list

This could be by design, though in the case of USE INDEX it sounds weird to me. Why? Because if none of the indexes mentioned in the list is usable, a full table scan will happen.

Why is this a problem? Because in the real world queries are generated dynamic and evolve over time. Today’s optimisations could be tomorrow’s wrong hints. I had a case of a wrong USE INDEX preventing the use of the primary key.

Produces an error if the index doesn’t exist

Again, this could be by design, but in the case of IGNORE INDEX this seems to me not ideal. A …

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Replication Performance Enhancements in MySQL 8

Although it feels like it was only yesterday that Oracle released version 5.7 of their acclaimed MySQL Community Server, version 8 is already available as a development milestone release (DMR). No, you didn’t sleep through a bunch of releases; MySQL is jumping several versions in its numbering due to 6.0 being dropped and 7.0 being reserved for the clustering version of MySQL. This new version boasts numerous changes (and bug fixes), one of the most exciting of which are replication enhancements. This blog will provide an overview of the new replication enhancements, including new replication timestamps, additional information reported by performance schema tables, and how replication delay has been reduced by updating the relationship between replication threads to make them more efficient.

New Replication Timestamps

The most common task when managing a …

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MariaDB 5.5.59 now available

The MariaDB project is pleased to announce the immediate availability of MariaDB 5.5.59. This is a stable (GA) release. See the release notes and changelog for details. Download MariaDB 5.5.59 Release Notes Changelog What is MariaDB 5.5? MariaDB APT and YUM Repository Configuration Generator Thanks, and enjoy MariaDB!

The post MariaDB 5.5.59 now available appeared first on

MariaDB Server 5.5.59 now available

MariaDB Server 5.5.59 now available dbart Fri, 01/19/2018 - 11:07

The MariaDB project is pleased to announce the immediate availability of MariaDB Server 5.5.59. See the release notes and changelog for details and visit to download.

Download MariaDB Server 5.5.59

Release Notes Changelog What is MariaDB 5.5?

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Shinguz: Short term notice: Percona XtraDB Cluster training in English 7/8 February 2018 in Germany

FromDual offers short term a Percona XtraDB Cluster and MySQL Galera Cluster training (2 days) in English.

The training will take place in the Linuxhotel in Essen/Germany on February 7/8 2018.

There are already enough registrations so it is certain the training will take place. But there are still free places for some additional participants.

You can book online at the Linuxhotel.

Important: The Linuxhotel is nearly fully booked out. So accommodation is in nearby locations. The Linuxhotel will recommend you some locations.

The training is in English.

You can find the contents of this 2-day Percona XtraDB Cluster training …

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Enhanced replication monitoring in ProxySQL 1.4.4

ProxySQL and pt-heartbeat

The Percona toolkit provides a very useful script for more accurate replication lag monitoring called pt-heartbeat. The pt-heartbeat script provides replication lag metrics based on actual data that has been replicated and is more accurate than the Seconds_Behind_Master metrics gathered from the output of SHOW SLAVE STATUS. Seconds_Behind_Master relies purely on system time (i.e. current time - time the event executed on the master server). By default ProxySQL relies on the output of the SHOW SLAVE STATUS command in order to identify replicas that should be excluded from the backend connection pool when max_replication_lag has been configured for a server in the mysql_servers table.

Starting from ProxySQL version 1.4.4 a new feature has been introduced in order to leverage the data provided by pt-heartbeat and …

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Percona Monitoring and Management (PMM) 1.6.0 Is Now Available

Percona announces the release of Percona Monitoring and Management (PMM) 1.6.0. In this release, Percona Monitoring and Management Grafana metrics are available in the Advanced Data Exploration dashboard. We’ve improved the integration with MyRocks, and its data is now collected from SHOW GLOBAL STATUS.

The MongoDB Exporter now features two new metrics: mongodb_up to inform if the MongoDB Server is running and mongodb_scrape_errors_total reporting the total number of errors when scaping MongoDB.

In this release, we’ve greatly improved the performance of the mongodb:metrics monitoring service.

Percona Monitoring and Management (PMM) 1.6.0 also …

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This Week in Data with Colin Charles 24: more Meltdown, FOSDEM, Slack and reminiscing

Join Percona Chief Evangelist Colin Charles as he covers happenings, gives pointers and provides musings on the open source database community.

There is still much going on when it comes to Meltdown/Spectre in our world. Percona’s Vadim Tkachenko and Alexey Stroganov recently published Does the Meltdown Fix Affect Performance for MySQL on Bare Metal?. You also want to read Mark Callaghan’s excellent work on this: Meltdown vs MySQL part 1: in-memory sysbench and a core i3 NUC, XFS, nobarrier and the 4.13 Linux kernel, …

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