Getting wireless working on Ubuntu Macbook

I run Ubuntu 9.04 Januty on my Macbook. Previously installing Ubuntu 8.10, wireless worked automatically, for 9.04 it did not. This is what I did to fix it. Verify your Macbook is seeing the Broadcom controller.

Read more

Understanding more InnoDB MVCC

As I had written earlier in Understanding InnoDB MVCC , I am trying to understand why InnoDB is taking a lock on data during an UPDATE when I do not expect this to happen.

Read more

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.

Read more

Killing my softly with QUERY

The MySQL KILL command as the name suggests kills queries that are running. After identifying the Id using the SHOW PROCESSLIST command, the User of the connection/thread or a database user with SUPER privileges can execute KILL [id]; to remove the connection/thread.

Read more

Installing Perl RRD module – RRDs.pm

Perform a quick check if the module is available. $ perl -MRRDs -le 'print q(ok!)' Can't locate RRDs.pm in @INC (@INC contains: /usr/lib64/perl5/site_perl/5.8.8/x86_64-linux-thread-multi /usr/lib64/perl5/site_perl/5.8.7/x86_64-linux-thread-multi /usr/lib64/perl5/site_perl/5.8.6/x86_64-linux-thread-multi /usr/lib64/perl5/site_perl/5.8.5/x86_64-linux-thread-multi /usr/lib/perl5/site_perl/5.8.8 /usr/lib/perl5/site_perl/5.8.7 /usr/lib/perl5/site_perl/5.8.6 /usr/lib/perl5/site_perl/5.8.5 /usr/lib/perl5/site_perl /usr/lib64/perl5/vendor_perl/5.

Read more

An important Drizzle/MySQL difference

There are many features that are similar in MySQL and Drizzle. There are also many that are not. I’ve previously discussed topics like Datatypes and tables , SQL_MODE and SHOW .

Read more

The confusion over global and session status

I was trying to demonstrate to a client how to monitor queries that generate internal temporary tables. With an EXPLAIN plan you see ‘Creating temporary’. Within MySQL you can use the SHOW STATUS to look at queries that create temporary tables.

Read more

Benchmarking Drizzle with MyBench(DBD::drizzle)

With thanks to Patrick Galbraith and his DBD::drizzle 0.200 I am now able to test client benchmarks side by side with MySQL and Drizzle. For simple benchmarking with clients, generally when I have little time, I use a simple Perl framework mybench .

Read more

Verifying MySQL Replication in action

There is a very simple test to show MySQL replication in action and to also better understand the basics of MySQL Replication. With a configured MySQL environment we can run the following test on your MySQL master, and monitor the MySQL slave.

Read more

MiFi Installation woes

As I mentioned in MiFi Introduction I took the plunge and purchased a Verizon MiFi . I got this under a 2 year contract for $149.99 and $59.99 per month for 5GB of traffic.

Read more

MiFi Introduction

My first news of the Verizon MiFi was via Twitter when @DonMacAskill said “Think my iPhone 3G via MiFi is faster than AT&T 3G. Should I carry both all the time now?

Read more

Using statpack with SHOW STATUS

Mark Leith, on of the MySQL Support Team managers wrote some time ago a very nice utility I use often called Statpack . My use of Statpack is very simple. Take two snaphots of SHOW GLOBAL STATUS and compare to produce a text based version of the statistics.

Read more

The value of multi insert values

Baron got a great amount of response from his 50 things to know before migrating Oracle to MySQL . I’m glad I invited him as a fellow MySQL colleague to my presentation to the Federal Government on Best Practices for Migrating to MySQL from Oracle and SQL Server for his inspiration.

Read more

What is max_tmp_tables?

Recently I came across another configuration option I’d not heard of before. I profess to not know them all, however I do know when I find something unusual. If you are a beginner DBA, learn what is normal and expected, and identify what is out of the normal, investigate, research and question if necessary.

Read more