It has been a very very long working week-end for the technical team at Believe...
From MariaDB 5.2 to 5.5.28 some few QP regression still need  to be fixed.

From latin1 to utf8 very few indexes as to be modified, reaching the max index column size limit of 767 bytes for InnoDB. Some Url like Referer as been change to varbinary as the column content was already a mixed of encoding stored in latin1. 

Don' forget UTF8 is bad for in memory  workload as strings in …

Interested in learning more about MySQL as embedded database? In building highly available MySQL applications with MySQL and DRBD? Join our webinars this week! All information below.

Tuesday next week (November 20) we will provide an update about what's new in MySQL Enterprise Edition.

We have live Q&A during the webinars so you'll get the chance to ask all your questions.

Top 10 Reasons to Use MySQL as an Embedded Database

Tuesday, November 13
9:00 a.m. PT
Review the top 10 reasons why MySQL is technically well-suited for embedded use, as well as the related business reasons vendors choose MySQL initially, over time, and across product-lines.
…

A common task in sharded database environments is to copy some chunk of production data from one physical server to another in a way which is transparent for users who may be actively making changes.  One pattern is to use replication to keep the target data up to date with any changes until the moment at which you change your application configuration and your users start writing their data to the new shard's location.  However, to use replication, you need to copy data from one system to another in a manner which is consistent to a specific point in time.  This lets you record the binary log position from which you begin replicating, ensuring that no data has been either lost or duplicated.

There are many ways to do this, and many of the existing tools rely on copying the entire source database.   Here's a few choices:

1. …

One of the optimizations we have introduced in MariaDB 5.5 is Extended keys. The idea behind it is rather simple. Inside InnoDB, every secondary index has an invisible suffix of primary key columns. That is, when you create an index:

ALTER TABLE innodb_tbl ADD INDEX (column1, column2);

you’re actually creating this

ALTER TABLE innodb_tbl ADD INDEX (column1, column2, primary_key_column1, …, primary_key_columnN);

The index is extended with primary key columns. SHOW KEYS does not show these extra key parts, but they are there.

Traditionally, MySQL optimizer was half-aware of these extra columns. It knew that doing an index-only scan on InnoDB’s secondary key would read the primary key columns also, and used this property. On the other hand, the optimizer was not able to use the extra columns to do a …

Users are safer

MySQL 5.6.8 was announced a few days ago. You can download it from the MySQL downloads page

This is the second release candidate of MySQL 5.6, and it is strange. My understanding of a release candidate is something that is stable, its features committed long time ago, and the release will just attempt to fix bugs. Instead, there are features that were not in the first release candidate. This one strikes me as really odd (quoting from the announcement) :

On Unix platforms, mysql_install_db supports a new option, --random-passwords, that provides for more secure MySQL installation. Invoking mysql_install_db with this option causes it to perform the following actions in addition to its normal operation: …

Log writer process of Oracle is one of the most revered background process, a real work horse, a real charming darling who keeps the whole Oracle database system consistent and humming beautifully and many technologies in Oracle sprout from this good old process. Consistency is the key in database systems, and so in the Log...

Being a MySQL DBA is more than just being able to understand the explain command to optimize a query.  The best optimized queries in the world are worthless with the database is down.

Some of the big responsibilities with being a MySQL DBA include monitoring, backup and recovery. This is a high level overview of those topics.

Monitoring:

A single monitor is just not good enough. If you are running a Nagios server with the MySQL plugins that is a great start. This  should not be your only solution. The first thing that should be added is another remote Nagios server to monitor the 1st master …

Continuent is proud to sponsor Percona Live MySQL Conference: London 2012!  Don't miss these five (5) talks by our database replication and clustering stars:

Keynote: Future-Proofing MySQL for the World-Wide Data Revolution, by Robert Hodges Why, What, and How of Data Warehouses for MySQL, by Robert Hodges Multi-master, Multi-site MySQL Databases Made Easy with Continuent Tungsten, by Robert

MySQL Connector/Net 6.6, a new version of the all-managed .NET driver
for MySQL has been released.  This is the GA, recommended for use in production environments.
Major features included are EF 4.3 support, Stored routines debugger integrated into Visual studio, Pluggable authentication & VS2012 support.

VISUAL EXPLAIN will be come a standard tool in your DBA toolbox but you will need later versions of both MySQL Workbench and MySQL Server. The examples here were created with Workbench 5.2.44 and MySQL 5.6.8, the latest Release Candidate of MySQL 5.6. And both are available for free from http://Dev.MySQL.Com.

Last time I took this query

SELECT City.Name, Country.Name
FROM City
JOIN Country on (City.CountryCode=Country.Code)

and received this illustration of what the optimzer is planning to do.

Figure 1

But what is the picture telling us? The red block in the lower left maked Country(ALL) with the ’239′ above is letting us know that there will need to be full table scan of the Country Table from the ALL by …