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Displaying posts with tag: MySQL (reset)
Deploy a MySQL Cluster step by step in Linux

Before proceeding installation things , go through cluster basics from the MySQL website and forums. It will be helpful to easily understand installation and configuration. First time is difficult to get things to done in one shot is not possible , no problem will learn it .
MySQL Cluster Installation will be mostly done by two ways.,

  1. Using binaries
  2. rpm(Rethat,CentOS..,)

 Different Linux flavors has different methods to install format , here I have explaining with CentOS7 .

1.Have prepared two different machines to install MySQL Cluster . First you have to login two different machines

Two VM Machines

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Helgrind and MySQL 5.7

Valgrind's helgrind tool identifies data races and lock deadlocks in multi-threaded programs.  Since the MySQL server is a multi-threaded program, can helgrind find any issues in the MySQL server?

A simple test that does nothing except start up the MySQL server and shut it down is run on the MySQL test suite with memcheck and with helgrind.  For this simple test on MySQL 5.7.7, the memcheck run is nice and clean but the …

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MySQL Permission denied error 13 and solution

MySQL ERROR 1018 (HY000): Can't read dir of './sakila/' (errno: 13 - Permission denied) caused due to moving database to a different partition and using softlink on CentOS and it's fix for SELinux.

The post MySQL Permission denied error 13 and solution first appeared on Change Is Inevitable.

MYSQL Sandbox 3.0.55 and new Github replication scripts


Both MySQL and MariaDB have been busy, each introducing new features, sometimes creating the same feature, often with different syntax.

This is sometimes good for users, who have a wide choice. And sometimes it is bad, as once you are used to the deployment and syntax of one flavor, it is hard to switch to a different one. This problem is enhanced if you are dealing with an application, MySQL Sandbox, that needs to work well with all flavors.

The latest releases of MySQL Sandbox (3.0.51 to 3.0.55) have been necessary to solve minor and major troublesome points with MySQL 5.7.8 and MariaDB 10.1.

The current version (3.0.55) can install all the newest releases, including replication with MySQL 5.7.8 which suffers from a compatibility bug (better explored in a separate article). …

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Log Buffer #432: A Carnival of the Vanities for DBAs

Yet again, this log buffer edition brings some rich blog posts from Oracle, SQL Server and MySQL.

Oracle:

  • Installing Oracle XE, ORDS and Apex on CentOS
  • Major Growth is Expected in the DBaaS Space. Are Your Skills Ready?
  • How to Hide Actions in OBPM 12c Workspace
  • You can configure auto refresh for ADF BC cached LOV and this works out of the box, no special coding is needed.
  • Search and …
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Bypassing SST in Percona XtraDB Cluster with binary logs

In my previous post, I used incremental backups in Percona XtraBackup as a method for rebuilding a Percona XtraDB Cluster (PXC) node without triggering an actual SST. Practically this reproduces the SST steps, but it can be handy if you already had backups available to use.

In this post, I want to present another methodology for this that also uses a full backup, but instead of incrementals uses any binary logs that the cluster may be producing.

Binary logs on PXC

Binary logs are not strictly needed in PXC for replication, but …

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Unobvious “Unknown column in ‘field list'” error

Recently we got request from our customer that something is going wrong with their database and they’re are getting strange errors after each insert or update to specific table. The strangeness caused by “Unknown column ‘column-name’ in ‘field list'” message while this column was existing in this table. Our investigation shown that this was caused by trigger on the table they were trying to do the insert/update. This trigger did the insert to another table where the mentioned column didn’t exist.

Let me show you example:

create test DB and 2 test tables:

create database test;
use test;

create table t1 (field1 int auto_increment not null, field2 varchar(10), field3 varchar(10), primary key(field1)) engine=innodb;
create table t2 (field1 int, field2 varchar(10)) engine=innodb;

Then create a new insert trigger on t1 table:

delimiter ##

create trigger insert_on_t1_to_t2
 after insert
 on t1 for each …
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Bypassing SST in Percona XtraDB Cluster with incremental backups

Beware the SST

In Percona XtraDB Cluster (PXC) I often run across users who are fearful of SSTs on their clusters. I’ve always maintained that if you can’t cope with a SST, PXC may not be right for you, but that doesn’t change the fact that SSTs with multiple Terabytes of data can be quite costly.

SST, by current definition, is a full backup of a Donor to Joiner.  The most popular method is Percona XtraBackup, so we’re talking about a donor node that must:

  1. Run a full XtraBackup that reads its entire datadir
  2. Keep up with Galera replication to it as much as possible (though laggy donors don’t send flow control)
  3. Possibly still be serving application traffic if you don’t remove Donors from rotation.
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innodb_fast_checksum=1 and upgrading to MySQL 5.6

The Percona version of MySQL has been such a good replacement for the generic MySQL version that many of the features and options that existed in Percona have been merged into the generic MySQL. Innodb_fast_checksum was an option added to … Continue reading →

How to configure WEBM

Architecture of WEBM system.

Reference:

http://www.vmcd.org/2014/10/webm_v2-has-been-released/
http://www.vmcd.org/2014/09/webm-mysql-database-performance-web-monitor/

View this PDF:

http://www.vmcd.org/docs/How%20to%20configure%20WEBM.pdf

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