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MySQL Feed

Oracle MySQL resources, news, and support articles.

OpenStack Dev Tip — Easily Pull a Review Branch

Just a quick tip for developers working on OpenStack projects that work on multiple development machines or want to pull a colleague’s code from the Gerrit review system and test it locally.

Reading results of SHOW statements, on server side

SHOW statements are show stoppers on server side. While clients can get a SHOW statement as a result set just as any normal SELECT, things are not as such on server side.

On server side, that is, from within MySQL itself, one cannot:

SELECT `Database` FROM (SHOW DATABASES);

One cannot:

DECLARE show_cursor CURSOR FOR SHOW TABLES;

One cannot:

MySQL Tech Tour Event – Montreal

Register now for the MySQL Tech Tour Event – Montreal.

Please join us for our first Canadian MySQL Tech Tour event event hosted by Oracle MySQL experts and learn more about Oracle’s strategy for MySQL, including continued investment in the world’s most popular open source database. Register for either Session 1 or Session 2 of this Tech Tour Event.

Speaking in Denver

Following a heavy schedule in the last month speaking in Tokyo, Beijing, Manila and Auckland it is nice to be on home soil for upcoming speaking.

Xfce is the new Gnome 2

I've recently had it with Ubuntu's Unity.

Wait, why Unity?

Because my gdm was consuming so much CPU my laptop had its fan working non-stop. I've researched and tweaked and installed and removed - and finally moved to Unity to solve that. There may have been another solution, but that's an old story now.

Should MySQL update the default innodb_log_file_size?

Now that InnoDB is the default storage engine in MySQL, is it time to update the default configuration for the InnoDB log file size (innodb_log_file_size) setting?

In general, there are two settings that simply can’t be left at their historical defaults for a production installation. MySQL 5.5 increased the default buffer pool size to something more sane (128MB instead of 8MB), but the log file size remains at 5MB. That’s 10MB total, because there are two logs by default.

Status update on High Performance MySQL

The third edition is nearly done. I’ve committed first drafts of all chapters, and all but one appendix. I need to do the last appendix and then rewrite the preface, which is a few days of work at my current pace. After that, it’s the usual tech review, copyediting, updates to figures, etc — and then it’s off to production.

MySQL opening .frm even when table is in table definition cache

or… “the case of Stewart recognizing parameters to the read() system call in strace output”.

Last week, a colleague asked a question:

I have an instance of MySQL with 100 tables and the table_definition_cache set to 1000. My understanding of this is that MySQL won’t revert to opening the FRM files to read the table definition, but we can see from strace:

Bug#12704861

As Mark pointed out, there isn’t a lot of detail in the release notes about what could potentially be a very serious problem that is fixed in MySQL 5.1.60. I’ll repeat here the full documentation from the release notes:

“InnoDB Storage Engine: Data from BLOB columns could be lost if the server crashed at a precise moment when other columns were being updated in an InnoDB table. (Bug #12704861)”

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