Since version 3.6 MEB supports backups to tape through the SBT interface.

The officially supported tool for such backups to tape is Oracle Secure Backup (OSB).

But there are a lot of other Storage Managers. MEB allows to use them through the SBT interface. Since version 3.7 it also has option --sbt-environment which allows to pass environment variables, not needed by OSB, to third-party managers. At the same time MEB can not guarantee it would work with all of them.

This month we were contacted by a customer who wanted to use IBM Tivoli Storage Manager (TSM) with MEB. We could only say them same thing I wrote in previous paragraph: this solution is supposed to work, but you have to be pioneers of this technology. And they agreed.

They agreed to be the pioneers and so the story begins.MEB requires following options to be specified by those who want to connect it to …

While working through prepared statements in MySQL, there was an interesting MySQL regular expression question raised. A student wanted to know how to address the following error message:

ERROR 1139 (42000): Got error 'repetition-operator operand invalid' FROM REGEXP

They had substituted * for a .+ in a metasequence. A metasequence is a parenthetical expression that evaluates based on multiple alternative conditions, and the pipe (|) acts as an OR operator. The full code example is found on page 482 of the Oracle Database 11g & MySQL 5.6 Developer Handbook. The student’s change would have worked without an …

I guest-posted on Fusion-io’s blog about the database’s working set size and the interplay with fast Flash storage. It’s written from a MySQL point of view, but it’s applicable to many types of systems.

Further Reading:

• 6 ways to stay sane while working from home
• How to understand SQL joins
• How to understand key length limitations in MySQL
• …

Many backup tools including Percona Xtrabackup, MyLVMBackup and others use FLUSH TABLES WITH READ LOCK to temporary make MySQL read only. In many cases the period for which server has to be made read only is very short, just few seconds, yet the impact of FLUSH TABLES WITH READ LOCK can be quite large because of the time it may take to complete this statement. Lets look at what the problem is.

As of MySQL 5.5 FLUSH TABLES WITH READ LOCK does not work as optimally as you could think it works. Even though with general lock compatibility guidelines Read Lock should not conflict with another Read Lock, it does for this statement, and as such it has to wait for any SELECT statement to complete in order to complete locking tables. This means if you have …

I’m speaking at POSSCON in Columbia,SC next week (March 28). My talk will be about Open Source software Percona Produces – Percona Server, Percona Xtrabackup, Percona Toolkit, Percona XtraDB Cluster. If you want to get a birds eye view about Open Source software Percona has created this is a great talk to attend.

We’re also Sponsoring event this year so we encourage you to come by and say Hi to us at the Expo hall Booth.

If you’re also attending and would like to meet up to have a chat, please drop me a note.

Many people use mysqldump –single-transaction to get consistent backup for their Innodb tables without making database read only. In most cases it works, but did you know there are some cases when you can get table entirely missing from the backup if you use this technique ?

The problem comes from the fact how MySQL’s Transactions work with DDL, In particular ALTER TABLE. When ALTER TABLE is Performed in many cases it will Create temporary table with modified structure, copy data to that table and when drop original table and rename such temporary table to original name.

How does data visibility works in this case ? DDLs are not transactional and as such the running transaction will not see the contents of old table once it is dropped, transaction also will see the new table which was created after transaction was started, including table created by ALTER TABLE …

This week we give an overview of Percona Live and what we think are the highlights, including which sessions we recommend for beginners and which we cannot wait to see for ourselves.

On Tuesday June 5th, 2012, a MySQL Innovation Day is being hosted at Oracle’s Conference Center in Redwood Shores, California. The MySQL Innovation day will feature multiple “lightning” talks by Oracle’s MySQL Engineers, If you cannot make it out to California, the lightning talks will be available via a live webcast, too - so either way, save the date! Unfortunately there's no link yet.

MariaDB 5.5 beta announcement

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On Wednesday this week Oracle held its first MySQL Developer Day in France. The room was packed with close to 100 people eager to learn more about MySQL.

We got great feedback from the attendees who could hear about the new MySQL Cluster 7.2 features, NoSQL Access to MySQL and MySQL Cluster, MySQL performance tuning in MySQL 5.5 and in MySQL 5.6…and more.

Sessions included

• MySQL Essentials
• MySQL Replication and Scalability
• Developing MySQL Applications with Java and PHP
• MySQL Cluster
• Testing early releases of MySQL in a sandbox (by guest speaker and Oracle ACE Director for MySQL Giuseppe Maxia)
• MySQL Performance Tuning
• MySQL Enterprise Edition Management Tools
• Developing MySQL applications for ISVs & OEMs

Thank you to all attendees for your active participation, and to all speakers for great and engaging …

Getting two sets of information from one table in a select statement often leads people to write subselects, but it really doesn't matter that this is the same table twice, we can just give it a new alias and treat it as if it were a different table. This is one of those techniques where, once you've seen it, it's really obvious, but until that point it can be very confusing. I explained this to someone else recently, so I thought I'd capture it here in case it's helpful to anyone else.

Consider that tried-and-tested example: employees and managers. Here's the staff table from the database (today's imaginary data isn't particularly imaginative, sorry):

mysql> select * from staff;
+----+------------+-----------+------------+
| id | first_name | last_name | manager_id |
+----+------------+-----------+------------+
|  1 | Hattie     | Hopkins   |          4 |
|  2 | Henry      | Hopkins   |          4 |
|  3 | Harry      | …

Getting two sets of information from one table in a select statement often leads people to write subselects, but it really doesn’t matter that this is the same table twice, we can just give it a new alias and treat it as if it were a different table. This is one of those techniques where, once you’ve seen it, it’s really obvious, but until that point it can be very confusing. I explained this to someone else recently, so I thought I’d capture it here in case it’s helpful to anyone else.

Consider that tried-and-tested example: employees and managers. Here’s the staff table from the database (today’s imaginary data isn’t particularly imaginative, sorry):

mysql> select * from staff;
+----+------------+-----------+------------+
| id | first_name | last_name | manager_id |
+----+------------+-----------+------------+
|  1 | Hattie     | Hopkins   |          4 |
|  2 | Henry      | Hopkins   |          4 |
|  3 | …