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MySQL schema maintenance



At CodeBits I had my first session about MySQL schema maintenance. I covered the basic command line possibilities before coming to the recommended tool, MySQL Workbench.
The slides are available at slideshare.


Interesting questions: ([updated] with answers from the development team

  • [Q] Are there plans to administer MySQL Cluster with Workbench?
    [A] Not that we know of.
  • [Q] Can Workbench deal with user permission maintenance across servers? (especially in cases where development and production users can't have …
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MySQL Parallel Query Processing of SSB Queries via InfiniDB

Let's take a look at MySQL parallel query processing with the InfiniDB storage engine with ~ 6 billion row fact table with the Star Schema Benchmark (SSB).


The star schema benchmark description and a data generator (dbgen) can be found here: http://www.cs.umb.edu/~xuedchen/research/publications/ .  The SSB benchmark modifies TPC-H/DBT-3 following data warehousing rules as described in some of the publications.


Note:  The load files for the fact table as emittRead More...

MySQL Parallel Query Processing of SSB Queries via InfiniDB

Let's take a look at MySQL parallel query processing with the InfiniDB storage engine with ~ 6 billion row fact table with the Star Schema Benchmark (SSB).


The star schema benchmark description and a data generator (dbgen) can be found here: http://www.cs.umb.edu/~xuedchen/research/publications/ .  The SSB benchmark modifies TPC-H/DBT-3 following data warehousing rules as described in some of the publications.


Note:  The load files for the fact table as emittRead More...

A replacement for C at last?

Wow, those Google guys sure keep spitting out new products. Barely had I finished my first shaky \/\/ave message when to my surprise I found out they have done what I have secretely dreamt of for the past five years - without getting round to it, obviously - they have created a new low-level language. For us poor souls stuck in C/C++ drudgery, this is amazing news. I'ts been over 20 years since something on this magnitude happened on the "system languages" frontier. Not counting Ada 95, nothing has happened as far as low-level languages are concerned.
Now, while you "web" guys might not hold a new language high in esteem - after all you are very badly spoiled - you get a new language complete with a framework and an IDE every other year: Ruby on Rails, PHP, Rebol, vb.net or what have you. But a new language that tackles the actual machine, now that's something you don't see every day. Where you can write stuff that ... wait for it ... …

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Solaris Cluster 3.2 11/09 is now available

Solaris Cluster is a multi-system, multi-site high availability and disaster recovery solution that manages the availability of applications services and data across local, regional and geographically dispersed data centers. The Solaris Cluster environment extends the Solaris Operating System into a cluster operating system.

If you are following the Solaris Cluster product and features, you would have noticed extreme innovation by Sun in the high availability and disaster recovery space since the time we released our first HA product many years ago. For well over a decade, Solaris Cluster has been a market leader for providing business continuity and disaster recovery solutions to all mission critical business applications, spanning all the major industry segments.

Continuing with our tradition of innovation, we are pleased to announce another release - "Solaris Cluster 3.2 11/09" - an update to the Solaris Cluster 3.2 …

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MySQL currently not available in Debian testing

Due to a bug in britney, the Debian testing migration tool, MySQL is currently not available in testing. The issue is known and being worked on already, and it is documented in the Debian bug tracking system.

Update: Meanwhile the issue was fixed, MySQL is available in testing again.

MySQL currently not available in Debian testing

Due to a bug in britney, the Debian testing migration tool, MySQL is currently not available in testing. The issue is known and being worked on already, and it is documented in the Debian bug tracking system.

Update: Meanwhile the issue was fixed, MySQL is available in testing again.

InnoDB supports group commit, binlog does not

InnoDB supports group commit in the plugin. The binlog does not. There has been a feature request for this in InnoDB for a long time. There wasn't a request for the binlog until now -- see bug 49326.

The previous note from Domas describes one workaround -- use XFS. Another workaround is to not sync the binlog or sync it less frequently (sync_binlog=10), but then crash recovery between InnoDB and the binlog might fail. Battery backed RAID write cache also helps.

How to retain comments in MySQL statements

There is a lot of buzz lately around retaining comments in MySQL’s logs and MySQL Stored procedures (Routines). When analyzing a MySQL query, it’s nice to have a comment inside the query (or procedure) that can provide us with more info about the query. For example, When analyzing MySQL’s logs (like Slow Query Log or […]

New threadpool design

In MySQL 6.0 a threadpool design was implemented based on
libevents and mutexes.

This design unfortunately had a number of deficiences:
1) The performance under high load was constrained due to a global
mutex protecting libevent (see BUG#42288).

2) The design had no flexibility to handle cases where threads were
blocked due to either locking or latches. E.g. a thread held up by a
table lock will be kept in the threadpool as an active thread until
the table lock is released. If all threads are blocked in this state,
it's easy to see that also any query that want to release the table
lock cannot be processed since all threads in the thread pool are
blocked waiting for the table lock (see BUG#34797).

3) The design is intended to support very many connections but
didn't use the most efficient methods to do this on Windows.

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