New Features In MySQL 6.x

I’ve been editing a task description in our worklog:
WL#706 Add EXPLAIN support for other statements (UPDATE/DELETE).

Currently MySQL supports EXPLAIN SELECT but there have been requests for EXPLAIN UPDATE, EXPLAIN DELETE, and so on. In fact it’s my impression that the proposition in WL#706 (transform the statement to a SELECT and then say EXPLAIN SELECT) is not what people want. But that’s okay, while a worklog is an early stage we allow simple ’solutions’ that might disappear later.

I’ve been editing a task description in our worklog: WL#827. It has to do with CREATE SEQUENCE, ALTER SEQUENCE, and using “sequence generators” to get the next number in a sequence. After the editing, I was able to set the private flag to ‘NO’, so now you can see the specification here: http://forge.mysql.com/worklog/task.php?id=827.

As always, one can “vote” on a worklog task that’s in forge.mysql.com, or comment on the corresponding feature request in bugs.mysql.com. I wouldn’t hold out much hope for this one, though. It’s been around since 2003, and we’ve always deemed that it’s higher priority to make minor changes to our auto_increment facility.

The MySQL 5.4 “Azalea” version was scheduled for a feature freeze last week. Thus it’s getting clearer what will come with the next milestone in a few months. The following is not official information but it is what I can actually see.

What’s not in

Some features, which I expected and predicted would be in, are not in.
* WL#2360 Performance Schema. We’re now in the fifth month of the first code review.
* WL#2649 Number-to-string conversions. We’re still using VARBINARY a lot.
* WL#1326, WL#2377 GIS
* WL#4803 Pluggable Query Cache module
* WL#1213 Supplementary Characters. This feature works great but could disrupt upgrades.

I apologize if I got anyone’s hopes up. The tasks are not cancelled and I’m hopeful about the next milestone releases.

What’s in

BACKUP and RESTORE are in, provided you start the server with mysqld –new. Some people say the feature is disabled, but it’s not disabled in the latest download.

There will be changes related to the Innodb plugin made by our Oracle partners.

Other changes that I’ve blogged about previously are in, including SIGNAL/RESIGNAL. OUT parameters in prepared statements, Sinhala collation, and changes to INFORMATION_SCHEMA.PARAMETERS. Of course we’re billing Azalea as a bouquet of performance enhancements, but these visible features alone are a big deal, people have wanted them for a long time.