Monday I started at MariaDB working on ColumnStore. My interest in column store technology extends way back to the days as the MySQL evangelist at Kickfire, which was a compressing column store and "SQL CHIP" appliance. My initial tasks are documentation related, but I'll be helping with development, and of course testing it with Shard-Query, which is a great stress testing system.
Just a few days ago, I presented at the MariaDB Roadshow in London, and I had a lot of fun. While I had canned slides, I did know the topic intimately well, so it was good to get further in-depth. In addition, we had these MasterMind sessions, basically the place to get one-on-one time with Anders/Luisa/or me, I noticed that pretty much everyone said they were buying services afterwards (which more or less must mean the event was rather successful from that standpoint!).
In addition to that, I was happy to see that from attendee feedback, I did have the highest averages – thank you!
So here’s to repeating this in Paris next week — Gestion des données pour les applications vitales – …[Read more]
In MariaDB and MySQL, cursors create a temporary table.
Does this statement deserve a whole blog post? Apparently not. However, in some cases one does not expect a temporary table to be created:
SELECT ... FOR UPDATE: An exclusive lock is created, yes, but you still read data from a temporary table.
SELECT FROMa temporary table: you are reading from a temporary tables, yes, but an internal temporary table is created anyway.
A quick example:
CREATE TEMPORARY TABLE t ( id INT UNSIGNED AUTO_INCREMENT PRIMARY KEY ); CREATE PROCEDURE p() BEGIN DECLARE c CURSOR FOR SELECT id FROM t WHERE 0 LIMIT 0 FOR UPDATE; OPEN c; CLOSE c; END; MySQL [test]> SHOW STATUS LIKE 'Created_tmp_tables'; +--------------------+-------+ | Variable_name …
I’m happy to be back in London in May 2016, to talk at two events:
- The London MySQL Meetup Group – Monday May 9 – 6.30 PM – 9.00 PM – options for High Availability in the ecosystem that one would consider today. This is a cut down from my Percona Live tutorial, which had about 88 registered attendees and about that amount showed up and asked questions even through the break and after. I had a lot of fun, and I expect I will have similar fun in London talking about this area that has changed a lot in recent times.
- Data for the Enterprise – MariaDB Roadshow in London – Wednesday, May 11, 2016 from 9:30 AM to 2:00 …
Good news everyone! There’s video up for the talk I gave at Percona Live in April 2016 up: Why would I run MySQL/MariaDB on POWER anyway?
The talk is a general overview of POWER and why MySQL/MariaDB may be a good fit.
MySQL 5.7.12 was released more than 2 weeks ago. New features
introduced there in a form of "rapid plugins" are widely
discussed, but I am more interested in bugs reported by MySQL
Community users that are fixed there. Unfortunately I do not see
MySQL Community Release Notes by Morgan (like this) for quite a some time, so I have to
continue describing key bug fixes and name people who reported
and verified bugs in my "Fun with Bugs" series.
As usual, let's start with InnoDB bugs fixed:
- Bug #80070 - "allocated_size and file_size differ if create general tablespace outside datadir". It was reported by my former colleague from Percona …
MariaDB MaxScale is mentioned in many blog posts recently. It's
Application of the Year 2016 after all! I'd
like to test it, follow posts like this etc, all that on my favorite and readily
available testing platforms that are now Ubuntu of all kinds and,
surely, Fedora 23 (on my wife's workstation, the most powerful
hardware at hand).
My old habits force me to build open source software I test from source, and I do not want to even discuss the topic of "MaxScale binaries availability" that was quite "popular" some time ago. So, after building MaxScale 1.4.1 on CentOS …
MariaDB 10.1 introduced Data at Rest Encryption. By default we provide a file_key_management plugin. This is a basic plugin storing keys in a file that can be itself encrypted. This file can come from a usb stick removed once keys have been brought into memory. But this remains a basic solution not suitable for security [...]
Today the first MariaDB 10.2 alpha popped up and for the first time there is support for window functions.
I'll describe what's been announced, what's been expected, comparisons to other DBMSs, problems (including crashes and wrong answers), how to prepare, what you can use as a substitute while you wait.
I assume some knowledge of what window functions are. If you'd prefer an introductory tutorial, I'd suggest reading articles like this one by Joe Celko before you continue reading this post.
What's been announced
The MariaDB sources are:
The release notes
The source code trees -- the feature tree up till now has been …[Read more]