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Search Results for: primary key varchar

Store UUID in an optimized way

A few years ago Peter Zaitsev, in a post titled “To UUID or not to UUID,” wrote: “There is timestamp based part in UUID which has similar properties to auto_increment and which could be used to have …

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Generating test data from the mysql> prompt

There are a lot of tools that generate test data.  Many of them have complex XML scripts or GUI interfaces that let you identify characteristics about the data. For testing query performance and many other …

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Multi-Valued INSERTs, AUTO_INCREMENT & Percona XtraDB Cluster

A common migration path from standalone MySQL/Percona Server to a Percona XtraDB Cluster (PXC) environment involves some measure of time where one node in the new cluster has been configured as a slave of the …

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When (and how) to move an InnoDB table outside the shared tablespace

In my last post, “A closer look at the MySQL ibdata1 disk space issue and big tables,” I looked at the growing ibdata1 problem under the perspective of having big tables residing inside the so-called shared …

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Examining the TokuDB MySQL storage engine file structure

As we know different storage engines in MySQL have different file structures. Every table in MySQL 5.6 must have a .frm file in the database directory matching the table name. But where the rest of …

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A schema change inconsistency with Galera Cluster for MySQL

I recently worked on a case where one node of a Galera cluster had its schema desynchronized with the other nodes. And that was although Total Order Isolation method was in effect to perform the …

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Check for MySQL slave lag with Percona Toolkit plugin for Tungsten Replicator

A while back, I made some changes to the plugin interface for pt-online-schema-change which allows custom replication checks to be written. As I was adding this functionality, I also added the –plugin option to pt-table-checksum. …

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Percona Server with TokuDB (beta): Installation, configuration

My previous post was an introduction to the TokuDB storage engine and aimed at explaining the basics of its design and how it differentiates from InnoDB/XtraDB. This post is all about motivating you to give it …

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Row-based replication, MySQL 5.6 upgrades and temporal data types

Whither your rollback plan? MySQL 5.6 upgrades are in full swing these days and knowing how to safely upgrade from MySQL 5.5 to 5.6 is important. When upgrading a replication environment, it’s important that you …

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Parallel Query for MySQL with Shard-Query

While Shard-Query can work over multiple nodes, this blog post focuses on using Shard-Query with a single node.  Shard-Query can add parallelism to queries which use partitioned tables.  Very large tables can often be partitioned fairly …

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