Thanks Mauritz! I also noticed that the performance is getting worse by increasing the number of partitions. Was wondering how to keep the number of partitions constant when increasing the number of LDM threads by the least effort.

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Thanks Mauritz, you are right. I’ll update the post but still the explain plan is confusing!

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Dear MySQL Users,

A new GA (general availability) version of MySQL Connector/C has
been made available: MySQL Connector/C 6.1.9 GA. The MySQL
Connector/C provides a C API for connecting client applications to
the MySQL Server 5.5 or newer.

You can download the production release at:

http://dev.mysql.com/downloads/connector/c/1.1.html

MySQL Connector C (Commercial) will be available for download on the
My Oracle Support (MOS) website. This release will be available on eDelivery
(OSDC) in next month’s upload cycle.

We have improved the driver since the last GA release. Please see the
documentation and the CHANGES file in the source distribution for a
detailed description of bugs that have been fixed. Bug descriptions are
also listed below.

Enjoy!

…

This post will be updated as soon more information comes along.

This developer version wasn’t released yet, when it does, use at your own risk.

Oracle released the development version of MySQL 8.0.0-dmr on September 12th of 2016. Since then, the team have been working on the 8.0.1 development milestone. You can find the partial change list here.

The objective here is try to explain how this will have any real world impact for you from 8.0.1. Please remember though, that any changes made to this version will not be final until the General Availability (date not currently set).

These topics are aimed at the Software Engineering side and not DBA and this is why Replication, for instance, is not covered …

FOSDEM is happening again in Brussels, and as usual, there will there be a MySQL and Friends Devroom. We can’t really imagine having a FOSDEM without having a MySQL and Friends Community Dinner, so here we are again..

Like the last couple of years, we have rented the same private space at ICAB, more detailed directions below.

You can buy tickets for the dinner at https://fosdem2017mysqlandfriendscommunitydinner.eventbrite.com

The listed ticket price includes a selection of Belgian Speciality Beers and food will be Belgian food served by a new (and improved) caterer:  …

For PARTITION_BALANCE see http://dev.mysql.com/doc/refman/5.7/en/create-table-ndb-table-comment-options.html

Note, that the default number of partitions are the least that in general spread the write load evenly among all LDM-threads. My personal belief is that very few applications will have an overall gain from changing the default PARTITION_BALANCE.

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This post discusses the next MySQL development milestone: MySQL 8.0.1.

From the outset, MySQL 8.0 has received plenty of attention. Both this blog (see the MySQL 8.0 search) and other sites around the Internet have covered it. Early reviews seem positive (including my own MySQL 8.0 early bugs review). There is plenty of excitement about the new features.

As for early feedback on MySQL 8.0, Peter Zaitsev (Percona CEO) listed a set of recommendations for benchmarking MySQL 8.0. I hope these get reviewed and implemented. …

The default sharding key is still the primary key!

To see that 7.5.4 does not behave as hidden pk case in 7.2.26, look also in the other columns of explain output. The partitions column should be ignored for NDB tables.

Still, you found a bug. The explain output should not depend on how partitioning is specified as long as it is the same.

For NDB the partition pruning is actually not done by the optimizer in MySQL server but within NDB itself.

To inspect the table definition used within NDB one can use ‘ndb_desc -d shard_check_pk’ it should reveal that there are no extra hidden columns, and also that the sharding key called distribution key in NDB is the same as the primary key.

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Helsinki, Finland & London, UK  – January 9th 2017 – Codership, whose Galera Cluster technology brings high availability (HA) and scalability to open source databases worldwide, has seen its technology break the one million download barrier. Codership’s customer roster has grown over 100 percent thanks to the adoption of OpenStack by enterprises and the recent strategic partnership with MariaDB.

Galera has been recognised as the most widely used OpenStack High Availability technology for the second year in a row. According to the OpenStack Survey 2016, one-third of users rely on Galera Clusters running on MariaDB and MySQL.

To cope with an increase of customer demand coming from various industries such as financial services, retail and telecoms, Codership has grown its engineering hires by 50 percent. The new team members will ensure Galera continues to deliver on its mission to protect …

This one is for all MySQL-DBA's, which are working on macOS. Since the Apple OS has a rather peculiar way of starting and stopping MySQL, compared to Linux, you can run into some issues. These problems occur especially, if you have no access to the GUI.

Preparation

Put skip-grant-tables into the mysqld section of the my.cnf. A my.cnf can be found in /usr/local/mysql/support-files. You MUST work as root for all the following steps.

shell> sudo -s
shell> vi /usr/local/mysql/support-files/my-default.cnf

...
[mysqld]
skip-grant-tables
skip-networking
...

Save the configuration file! (In vi this is "[ESC] + :x")

Continue with stopping MySQL:

launchctl unload /Library/LaunchDaemons/com.oracle.oss.mysql.mysqld.plist

Restart MySQL, so skip-grant-tables becomes active:

launchctl load …