PUBLIC MARKS with tags "groupe:clever age" & mysql

I gave a tutorial at OSCON last week on tuning MySQL queries, the EXPLAIN statement, the optimizer, and benchmarking. I've gone ahead and put the tutorial materials online now:

talks about current state behavior and performance properties of Innodb, Falcon, PBXT and SolidDB Storage Engines

The tool is called Querysniffer and it grabs MySQL queries from “the wire”. It does this in real time. You don’t have to stop/start your MySQL server or have to enable the general query log. You can start and stop the Querysniffer at any time.

In this article, we're going to go through the entire process of installing, configuring and testing DRBD, Heartbeat and MySQL running in a 2 node cluster environment. This will be a bare bones configuration, best practices and security will take a back seat while we learn how all the different pieces work together.

RAID is dying. Shocked? The prediction might be a bit early for some folks. It’s still somewhat conventional for some people to think that RAID is a conservative way to scale your IO.

The high availability features include support for semi-synchronous replication, mirroring the binlog from a master to a slave, quickly promoting a slave to a master during failover, and keeping InnoDB and replication state on a slave consistent during crash recovery. The manageability features include new SQL statements for monitoring resource usage by table and account. This includes the ability to count the number of rows fetched or changed per account or per table. It also includes the number of seconds of database time an account uses to execute SQL commands.

Securing plain text passwords in MySQL is NEVER a good idea. As a DBA you should take great care in protecting the users' information. Fortunately MySQL provides you with several options to protect passwords.

As a general rule, we encourage everyone to upgrade from MySQL 4.0 to a newer release.

Here are the items from the MySQL 5.0 release notes that are marked Warning: Incompatible change:

In general, you should do the following when upgrading from MySQL 4.0 to 4.1:

# By 2008, open source databases will be used by more than 70% of IT organizations # By 2008, MySQL will be a serious choice for mission critical applications

PHP Data Persistence and ORM Tool

A global transaction involves several actions that are transactional in themselves, but that all must either complete successfully as a group, or all be rolled back as a group. In essence, this extends ACID properties “up a level” so that multiple ACID transactions can be executed in concert as components of a global operation that also has ACID properties. (However, for a distributed transaction, you must use the SERIALIZABLE isolation level to achieve ACID properties. It is enough to use REPEATABLE READ for a non-distributed transaction, but not for a distributed transaction.)

So what would you do? I made some preliminary notes, here’s the full account of what I did do.

Prométhée est un intranet pédagogique et administratif écrit en PHP dont le code est placé sous licence GNU/GPL.

Prométhée est un intranet pédagogique et administratif écrit en PHP dont le code est placé sous licence GNU/GPL.