The 5.7.5 DMR is now available, and we’ve made some changes to our build system in this one, so I wanted to spend some time discussing how you would now build MySQL.

When we released our April labs release, I wrote about building MySQL with Boost. Now that the first GIS work using Boost.Geometry has passed all the hurdles and landed in a development milestone release (DMR), it’s time to revisit the topic. From now on (5.7.5 and newer), MySQL needs Boost headers to compile. It’s not optional.

We got a few bug …

When ALTER TABLE crashes MySQL server it leaves orphaned records in InnoDB dictionary. It is annoying because next time you run the same ALTER TABLE query it will fail with error:

ERROR 1050 (42S01) at line 1: Table 'sakila/#sql-ib712' already exists

The post explains why it happens and how to fix it.

When you run ALTER table InnoDB follows the plan:

1. Block the original table
2. Create an empty temporary table with the new structure. The name of the new table is something like #sql-ib712.
3. Copy all records from the original table to the temporary one
4. Swap the temporary and original tables
5. Unblock the original table

The temporary table is a normal InnoDB table except it’s not visible to a user. InnoDB creates a record in the dictionary for the temporary table as for any other table.

If MySQL crashes in the middle of the …

http://www.percona.com/live/london-2014/sessions/mysql-cluster-101

We will be attending and participating in the OmniTI Surge Conference September 25 and 26. Stop by our booth and let us give you a demo of our product.

Owen Zanzal and Baron Schwartz will also be presenting: The GoLang Effect: How Go Changed Operations at VividCortex.

The session is Thursday 2:30 PM. Hope to see you there. If you cannot attend but would like to know more about Go, consider this webinar.

Here is a bit about the presenters:

Owen Zanzal

Twitter Handle: @AgentO3

Owen Zanzal is a developer at VividCortex, where he is on the operations team putting …

I was asked some questions on IRC last night about how the query example in libAttachSQL's code base works. For those who missed previous posts, libAttachSQL is a lightweight, non-blocking, Apache 2.0 licensed C connector for MySQL servers which I am developing for HP's Advanced Technology Group.

In this blog post I'm going to break down a basic query example and explain what is happening at each step. It is possible that this syntax may change slightly by the time we hit GA but it will be similar to this.

#include <libattachsql-1.0/attachsql.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>

Only one include is needed for the library itself, libattachsql-1.0/attachsql.h. The others are used for other functions in the code. …

It's been almost a year now since the initial release of MySQL Fabric. It is maturing and reached a GA state earlier this year as part of MySQL Utilities 1.4. Developers and architects are evaluating it for their applications, learning the capabilities of the system, and providing feedback for future features and usability enhancements. Connector/J has supported Fabric from the very beginning and continues to support the latest features. This blog post is an introductory level guide to using Fabric for high-availability from Java applications. Sharding features and Java APIs will be covered in a later post. The commands shown and feature descriptions are current for Fabric 1.5.1. In addition, Connector/J 5.1.32 and later support only Fabric 1.5 due to communication protocol differences from Fabric 1.4.

High-availability is a core concept in Fabric and is implemented by HA groups. An HA group is a set of servers configured with MySQL …

New to TokuDB® v7.5 is a feature we’re calling “Read Free Replication” (RFR). RFR allows TokuDB replication slaves to process insert, update, and delete statements with almost no read IO. As a result, the slave can easily keep up with the master (no lag) as well as brings all the read IO capacity of the slave for read-scaling your workload.

The goal of this blog is two-fold: (1) to cover why RFR is important and how RFR works and (2) to run a simple before/after benchmark showing the impact of RFR on a well known workload. Later this week I’ll post another blog showing other interesting use-cases for RFR beyond this first benchmark.

Read Free Replication: The Why and How

In MySQL, a replication slave does less work than the master because there is no need for a slave to execute SELECT statements (only INSERT, UPDATE, and DELETE). However, a MYSQL slave can struggle to keep up with the master because replication is …

Choosing the right backup solution is most important for any database. People always choose a backup solution that has the below qualities

 a) Minimal Downtime
 b) Consistent data
 c) Less restoration time

There are several backup solutions like mysqldump, mysqlhottcopy, Xtrabackup, raw copy using cp/rsync/scp (and of course MySQL Enterprise backup. we are not going to talk about it here) etc.., I always prefer mysqldump when the data size is small(few GBs) even if it locks the tables. But what if the data size is huge in TB's, you cannot bring down the DB for a whole day. No client is comfortable with this, they need minimal or no downtime. Percona's Xtrabackup actually comes in handy in such situations. Xtrabackup locks the tables only when dumping the meta data.

                But what we are really interested here is LVM …

Below are 10 common replication problems :

1)Session binlog :

Setting sql_log_bin = 0 will disable binary logging for the session. So any DML/DDL query executed within that session on the master will not be replicated to slave

Example:

Turn off binary logging on master :

mysql> set sql_log_bin = 0 ;
Query OK, 0 rows affected (0.00 sec)

Create table in reptest database ( on master )

mysql> create table reptest(ID int) ;
Query OK, 0 rows affected (0.01 sec)

mysql> show tables ;
+-------------------+
| Tables_in_reptest |
+-------------------+
| reptest           |
+-------------------+
1 row in set (0.00 sec)

Validate to see that table is not created on slave :

mysql> use reptest ;
Database changed
mysql> show tables ;
Empty set (0.00 sec)

2) Updating slave directly

Master and slave will get out of …

libAttachSQL Query Example

I was asked some questions on IRC last night about how the query example in libAttachSQL’s code base works. For those who missed previous posts, libAttachSQL is a lightweight, non-blocking, Apache 2.0 licensed C connector for MySQL servers which I am developing for HP’s Advanced Technology Group.

In this blog post I’m going to break down a basic query example and explain what is happening at each step. It is possible that this syntax may change slightly by the time we hit GA but it will be similar to this.

#include <libattachsql-1.0/attachsql.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>

Only one include is needed for the library itself, libattachsql-1.0/attachsql.h. The others are …