Slave on FromDual GmbH

How the Lack of a Primary Key May Effectively Stop the Slave

oli.sennhauser@fromdual.com (Oli Sennhauser) — Tue, 02 May 2017 09:50:52 +0000

Most (relational) DBAs and DB application developers know the concept of a primary key (“PK”) and what it is good for. However, much too often one still encounters table definitions without a PK. True, the relational theory based on sets does not need a PK, and all operations (insert, select, update, delete) can also be done on tables for which no PK was defined. If performance doesn’t matter (or the data volume is small, a typical situation in tests), the lack of a PK does not immediately cause negative consequences.

Replication channel failover with Galera Cluster for MySQL

oli.sennhauser@fromdual.com (Oli Sennhauser) — Thu, 19 Jun 2014 07:05:38 +0000

Sometimes it could be desirable to replicate from a Galera Cluster to a single MySQL slave or to an other Galera Cluster. Reasons for this measure could be:

MySQL Multi-Master – Single-Slave – Replication (Episode 2)

oli.sennhauser@fromdual.com (Oli Sennhauser) — Mon, 13 Oct 2008 16:17:00 +0000

Introduction

One of the features that make MySQL so great is its easy replication set-up. If you are experienced and know-how to do it, it takes you about 15 minutes to set-up a slave. What you have in the end is a replication from one master to one or several slaves. So you can build a top-down data stream pyramid and spread your data on many slaves.

MySQL Multi-Master - Single-Slave - Replication

oli.sennhauser@fromdual.com (Oli Sennhauser) — Thu, 21 Dec 2006 16:39:00 +0000

MySQL provides its replication for High Availability (HA) and for read Scale-out. Generally it is known that in a MySQL replication you can only replicate from one Master to many slaves. In this paper it is shown how a set-up can look like to replicate from two masters to one slave.