The following quirky dynamic SQL will scan each index of each table so that they’re loaded into the key_buffer (MyISAM) or innodb_buffer_pool (InnoDB). If you also use the PBXT engine which does have a row cache but no clustered primary key, you could also incorporate some full table scans. To make mysqld execute this on [...]
A catchy headline, and I believe more accurate than Oracle Puts the Squeeze on SMBs with MySQL Price Hike (Network World) and MySQL price hikes reveal depth of Oracle’s wallet love [MySQL Jacking up MySQL Prices] (The Register). Slightly more realistic is Oracle kills low-priced MySQL support (again The Register). First, let’s review what Oracle [...]
Open Query now has its own @openquery account on Twitter and Identi.ca so you can conveniently follow us there for announcements and tips – and also ask us questions! All OQ engineers can post/reply. The OQ site front page also tracks this feed. Previously I was posting from my personal @arjenlentz account with #openquery hashtag, [...]
You take a look at someone’s MySQL (or MariaDB) data directory, and see mysql foo bar -> foo What’s the issue? Identify pattern. What does it mean? Consequences. Is there any way it can be safe and useful/usable? Describe. Good luck!
So this is about a SELECT COUNT(*) FROM tblname without a WHERE clause. MyISAM has an optimisation for that since it maintains a rowcount for each table. InnoDB and PBXT can’t do that (at least not easily) because of their multi-versioned nature… different transactions may see a different number of rows for the table table! [...]
With Paul McCullagh’s PBXT storage engine getting integrated into MariaDB 5.1, it’s never been easier to it out. So we have, on a slave off one of our own production systems which gets lots of inserts from our Zabbix monitoring system. That’s possibly an ideal usage profile, since PBXT is a log based engine (simplistically [...]
When asking about up-time requirements set down in SLAs (Service Level Agreements) with our clients’ clients, we’d hear anything ranging from hours to the familiar five nines, but these days also simply 100% and otherwise penalties apply. From my perspective, there’s not much difference between five nines and 100%, 99.999% uptime over a year amounts [...]
This is a Request for Input. Dual MySQL masters with MMM in a single datacentre are in common use, and other setups like DRBD and of course VM/SAN based failover solutions are conceptually straightforward also. Thus, achieving various forms of resilience within a single data-centre is doable and not costly. Doing the same across multiple [...]
At this year’s conference, I was pleasantly surprised with the high level of interest in Open Query’s proactive services for MySQL and MariaDB, and specifically our focus on preventing problems, while explicitly not offering emergency services. I’ll describe what this is about first, and why I reckon it’s interesting. When you think about it, most [...]
A crosstab query is a specific query used to create aggregate reports on two or more fields, it’s a handy way to display summary information. At Open Query we have customers using that trick to display production schedules. The summary table is generated from the database to extract the manufacturing date (mand), unit number (unitn), [...]