After 10 years HackMySQL.com has been retired. The tools are archived at github.com/daniel-nichter/hackmysql.com

I began writing MySQL tools in 2004 because at the time there were none except for mysqldumpslow. I was a Unix sysadmin in a large datacenter, so I worked on many different servers and MySQL instances. Tools for any sufficiently complex system are a necessity. Imagine a car mechanic trying to work without basic tools like an oil filter wrench, torque wrench, or belt tensioner. That's what work with MySQL was like in 2004. Certainly, many people made their own tools, but I think I was the first to develop, document, and publish general-purpose MySQL tools. If I wasn't the first then it's a tie with Baron Schwartz, creator of Maatkit. In 2008 he hired me at …

Add mysqlidxchk.

Add mysqlsniffer.

Add mysqlsla.

Add mysqlreport.

With new year already in fast gear, bloggers are sparing no stone unturned to come up with innovative ideas. This Log Buffer edition is keeping pace with them as always.

Oracle:

While playing with 12c Scott tried the upgrade to the DEFAULT column syntax that now allows sequences.

This is an age old question and of course the answer depends on how you say “SQL”.

Happy New Year! Upgraded 12.1.0.1 Grid Infrastructure to 12.1.0.2 and applied the Oct 2014 PSU. Had an error during rootupgrade.sh as well, due to the ASM spfile being on disk instead of on ASM diskgroup.

If you (already) created your first …

Query caching is one of the prominent features in MySQL and a vital part of query optimization. It is important to know how it works as it has the potential to cause significant performance improvements – or a slowdown – of your workload.

The MySQL query cache is a global one shared among the sessions. It caches the select query along with the result set, which enables the identical selects to execute faster as the data fetches from the in memory. It is important to have everything identical, no new comments, spaces, or most significantly differences in the WHERE clause. Basically when you trigger a select query, if it is available in the cache; it fetches from there or it considers the query as a new one and will go to the parser.

Even though it has some nice advantages, the MySQL query cache has its own downsides too. Well, let’s think about this: If you are frequently updating the table, you are then invalidating …

First of all, Happy New Year!

IEEE Spectrum published a ranking of the most popular programming languages. Computational journalist Nick Diakopoulos wrote the article. While it may surprise some, I wasn’t surprised to find SQL in the top ten.

Nick weighted and combined 12 metrics from 10 sources (including IEEE Xplore, Google, and GitHub) to rank the most popular programming languages.

• Compiled programming languages (Java [#1], C [#2], C++ [#3], C# [#4], Objective-C [#16])
• Interpreted programming languages (Python [#5], JavaScript [#6], PHP [#7], Ruby [#8], Perl [#11], HTML [#12])
• Data languages (SQL [#9], MATLAB …

So assume you just uploaded the certificate you use to identify yourself to the MySQL server to Github or some other place it doesn't belong...and there is no undelete.

First: Don't panic.
Often a password is required besides a certificate to connect to the server. So someone with the certificate can't use it without the password. The certificate itself might be protected by a password, but that's really rare. Also access to MySQL and/or your account should be limited to certain IP's.

The next step is to revoke the certificate. This is possible since MySQL 5.6.3 by using a Certificate Revocation List (CRL).
A CRL is a list of the serials of the revoked certificates and signed by the CA. So this will only work if the certificates have unique serials.
…

At the last OOW MySQL Plugin for Oracle Enterprise Manager (OEM) was recognized as most popular MySQL product. If you don't have OEM installed, but want to test the plugin you can download OEM virtual box template. But, althought this is the easiest way to get started, you still need to make few additions. At least I had to do them when deployed such installation for MySQL Support Team.

Here they are. I prefer to use command line when possible.

0. Import virtual machine image and change network adapter to working one, then allow to connections via rdesktop:

sudo vboxmanage import VBox_EM12cR4.ova --vsys 0 --vmname  …