Locking

The Casual MySQL DBA – Operational Basics

So your not a MySQL DBA, but you have to perform like one. If you have a production environment that’s running now, what are the first things you do when it’s not running or reported as not running?

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Common MySQL Scalability Mistakes

This week I was one of the presenters at the first Surge Scalability Conference in Baltimore. An event that focused not just on one technology but on what essential tools, technologies and practices system architects need to know about for successfully scaling web applications.

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Understanding Innodb Transaction Isolation

The MySQL Innodb storage engine provides ACID compliance, the ‘I’ being isolation. There are four states defined in MySQL with the tx_isolation system variable, READ-UNCOMMITTED, READ-COMMITTED, REPEATABLE-READ and SERIALIZABLE. Generally MySQL installations do not modify the default value of tx_isolation = REPEATABLE-READ, however I have seen with a number of clients the default value has been changed to READ-COMMITTED.

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Understanding InnoDB MVCC

Multi versioning concurrency control (MVCC) is a database design theory that enables relational databases to support concurrency, or more simply multiple user access to common data in your database. In MySQL the InnoDB storage engine provides MVCC, row-level locking, full ACID compliance as well as other features.

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