After a year of testing, Sun Microsystems announced in April that thatMySql 5.1 was ready for GA release.  That was great news because it would be offering lots of new features and Open Source products are always priced right ) .

However, MySql’s original author, Michael “Monty” Widenius says that release by Sun was premature.  On his blog, he recommends treating the new features of MySQL 5.1 as BETA and to make sure that you test them thoroughly before placing into production.

He says there are 20 verified critical bugs in 5.1 that remain unaddressed and possibly as many as 35.  There are also more than 300 less critical bugs that are on the “to-do” list, but have no fix timetable.

He also documents several bugs, which could lead to database instability:

  • There is a bug that could cause an error when one is upgrading from 5.0 to 5.1 and a table in the database contains triggers – documented here

Check out his blog and you will see a TON more documented bugs.

So why would Sun release something as GA when it should have gone through some additional testing, perhaps?  Monty says:

The reason MySQL 5.1 was declared RC was not because we thought it was close to being GA, but because the MySQL manager in charge *wanted to get more people testing MySQL 5.1*.

Monty’s post is very candid and normally those types of discussions would be held behind closed doors, but such is the way of Open Source.  It is very… open.

So use MySQL 5.1, but be informed before you decide to upgrade and you should definately test it completely before you put it into production.