Our site went from weekly crashes during our two busiest nights to not even peeping this week (during the two busiest nights), and the only thing we changed was that we did some table maintenance. We hadn’t done table maintenance at least as long as I’ve been around, which is 6 months. We are a site with high volumes of both reads and writes. This article will talk about the care and feeding of tables; feel free to use this for justification to have a maintenance window, or even permission to run table maintenance statements.

MySQL uses a cost-based optimizer to best translate the written query into what actually happens. This means when you write:

SELECT foo FROM t1 INNER JOIN t2 USING (commonField);

The optimizer looks at the statistics for tables t1 and t2 and decides which is better:
1) To go through each item in t1, looking for a matching “commonField” in t2
or
2) To go …

Many people have some kind of reporting or auditing on their database. The problem is that the data grows very large, and lots of times there is data that can be purged. Sure, theoretically one never needs to purge data, but sometimes a “delete” flag just won’t work — when you search on the delete flag, a full table scan may be the most efficient way to go.

Of course, that’s not acceptable. And in many cases, say when you have users who no longer use the site but did in the past (and perhaps have billing data associated with them), you never want to get rid of them.

So what to do? Make a special reporting database, that gathers information from the production database(s). Use MyISAM tables, because a reporting server can afford to be behind the master, and MyISAM is better for reporting — better metadata. For something like a “Users” table, make 2 more tables:

1) DeletedUsers
2) AllUsers

…

By tim

Greg Linden of Findory wrote: "I've been enjoying your series on O'Reilly Radar about database war stories at popular startups. I was thinking that it would be fantastic if you could get Jeff Dean or Adam Bosworth at Google to chat a little bit about their database issues. As you probably know, Jeff Dean was involved designing BigTable and the Google File System. Adam Bosworth wrote a much discussed post about the need for better, large scale, distributed databases."

I followed up with mail to Jeff and Adam. Jeff wrote back briefly about BigTable: "Interesting discussion. I don't have much to add. I've been working with a number of …

Yesterday, I learned that I will be at this year?s Linuxtag Conference in Wiesbaden. Somehow, their proposal system sent out a confirmation on one of my proposals but was caught by my spam filter. Linuxtag guys, are you listening? Don?t send such important mails without a fullname next time.

Well, the topic that was accepted is ?SQL vs. LDAP? where I will introduce both systems and their pros & cons. Which systems makes sense in which environment, when to combine both worlds, what to avoid, etc. I will be on the train in 5 hours and have a 6 hours ride to get the slides done.

Additionally, I heritated another talk about MySQL Cluster. It will be the same slides I used from the latest Usergroup meeting in Hamburg. But since most people at the conference didn?t attend that meeting, it should be interesting and …

Round 2. Question 2? From the MySQL Quiz Show. (you had to be there)

I decided to start my own little blog on IT and programming. Little tidbits of information or other ideas as they come along.

MarkMySQL DBA & Programming Blog by Mark Schoonover

Hannah, Scarlet and I attended the Seattle Meetup, since we heard Arjen was planning on being in town. We went to the normal location, but the owner told me they were closed due to their entire staff being involved in the civil rights …

Hey all -

Some of you have already begun using the new Beta2, but many haven’t so I thought I’d remind you to download the new 5.1 Beta2 and give it a whirl. I’ve been playing with the CSV engine (which first came out in 5.0 in limited form, but is now fully ready for action in 5.1), recently and will be posting a new article to the MySQL Dev Zone soon on all the fun you can have with it.

Great seeing everyone at the recent User’s Conference!

Robin

P.S. Beta2 of 5.1 started with 5.1.9…

A public SVN tree for the MySQL Documentation is now online.

You can browse all source trees at http://dev.mysql.com/tech-resources/sources.html. The page includes source trees for the server, GUI tools, and Windows installer.

The Documentation SVN tree is at http://svn.mysql.com/svnpublic/mysqldoc/
, it can be browsed with your favorite browser or accessed with an SVN client.