The Drizzle Report is a weekly synopsis on drizzle development. This first report will contain more than just a weeks worth of development in order to catch up.

What has been removed from the initial MySQL source tree can be found at the MySQL Differences wiki page. Some of the highlights were the removal of the mysql database, TINY/MED/LONG BLOB, TINY/MED/LONG TEXT thespatial data types, and FULLTEXT indexes. Certain keywords were removed too like ENGINES, CLIENT and CONTRIBUTORS. Even drizzleadmin has been stripped down to just ping and shutdown.The long-standing MySQL ACL has been ripped out, and initial PAM authentication has been started.

Monty Taylor reports RIP: errmsg.sys, in its place is gettext which is a standard for outputting strings.

Comparing drizzle …

Brian is merging in a patch I’ve been working on that kills errmsg.txt, errmsg.sys and comp_err. In its place is (currently) a header file with a static list of error messages and codes. To handle the i18n of the messages, we’re starting to use gettext. Not only is this a standard thing, but it makes it much easier for us to translate all of the rest of the strings we output inside of Drizzle. (turns out, there are quite a few of them)

Soon I hope to be uploading a .pot file to launchpad so that the i18n work can get underway.

Next on the list as far as this goes, re-working how all of the error message lists are managed internally, and doing some thinking on why we have our own charset stuff that isn’t the system iconv() based stuff.

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Yesterday I spent some time trying to figure out how I can better support people who are running OSX. I came to the conclusion that it’s not possible for me to do this, and in fact, Apple doesn’t want me to. As part of that process, it made me rethink OpenSolaris a little bit. Here’s my list of things I like about OpenSolaris:

• It’s not OSX
• I can install it in a VM
• It’s trying to get packaging right
• It’s Free Software

Caveats to the above list:

• My reservations about a brand new ZFS-based packaging system
• It may be Free Software, but it’s CDDL

Thank you Sun, for not being the cess-pool of arrogant wanks that Apple is!

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The purpose of this post is to outline a general flow-chart for improving the performance of queryies in MySQL. Much has been written on using EXPLAIN to optimize queries, but there is a whole process that should be followed in order to maximize the effectiveness of query performance tuning. Following is a visual [...]

Today I’ve managed to finish initial version of our bounces-handler package we use for mailing-related stuff in Scribd.

Bounces-handler package is a simple set of scripts to automatically process email bounces and ISP‘s feedback loops emails, maintain your mailing blacklists and a Rails plugin to use those blacklists in your RoR applications.

This piece of software has been developed as a part of more global work on mailing quality improvement in Scribd.com, but it was one of the most critical steps after setting up reverse DNS records, DKIM and SPF.

The package itself consists of two parts:

• Perl scripts to process incoming email:
  • bounces processor — could be …

When I moved to the UK from Italy, now more than eight years ago, people asked me all the time "Why did you leave such a sunny place like Italy to move to England?". Well, first of all, the south east of England is not that bad. There is a decent number of sunny days in a year and the bright sky of a breezy morning is just fantastic. Second, my home town is Milan, in the middle of the Po valley, with foggy winters and humid summers, with temperatures between -15C and +38C over the year. And there is another point: no wind and no much rain, hence pollution. In Milan the pollution is so awful that almost one third of the working days in a year private cars cannot be used within the city, in the attempt of reducing emissions. When I was a child, my mum used to put a PVC cover over the washing line to avoid that clean clothes would get immediately dirty.

It is a long introduction, but it is probably worth it, because it fits almost …

Quite frequently I see customers looking at recovery as on ability to restore data from backup which can be far from being enough to restore the whole system to operating state, especially for complex systems.

Instead of looking just at data restore process you better look at the whole process which is required to bring system to the working state, including data consistency requirements and times. This has to be considered for different data loss scenarios which may happen.

Let us look at simple example - a master with 1TB of database size replicating to 50 servers in 5 different Data Centers via single Replication Relay server in each. Forget the single point of failure for the second and just think what problems we may have to deal with.

First lets look at the master. What may happen to it ? We can have Master having soft crash in which case it will be unavailable for some time but we can get all the …

Have you ever seen the replication stopped with message like this:

Last_Error: Could not parse relay log event entry. The possible reasons are: the master's binary log is corrupted (you can check this by running 'mysqlbinlog' on the binary log), the slave's relay log is corrupted (you can check this by running 'mysqlbinlog' on the relay log), a network problem, or a bug in the master's or slave's MySQL code. If you want to check the master's binary log or slave's relay log, you will be able to know their names by issuing 'SHOW SLAVE STATUS' on this slave.

This is relay relay log corruption and you can check details in the MySQL Error log file. The error message describes few reasons and indeed because there is little validation (ie no checksums) in the replication there are multiple reasons for bad event to show up in relay logs.

Really this is only one of various error messages you could see if relay log corrupted. You …

My post about contributing to Drizzle somehow ended up with a very old posting date to MySQL Planet.MySQL DBA & Programming Blog by Mark Schoonover