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Why You Should Avoid Using “CREATE TABLE AS SELECT” Statement

In this blog post, I’ll provide an explanation why you should avoid using the CREATE TABLE AS SELECT statement.

The SQL statement “create table <table_name> as select …” is used to create a normal or temporary table and materialize the result of the select. Some applications use this construct to create a copy of the table. This is one statement that will do all the work, so you do not need to create a table structure or use another statement to copy the structure.

At the same time there are a number of problems with this statement:

  1. You don’t create indexes for the new table
  2. You are mixing transactional and non-transactional statements in one transaction. As with any DDL, it will commit current and unfinished transactions
  3. CREATE TABLE … SELECT …
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Monitoring MySQL Backups With Datadog and TwinDB Backup Tool

Monitoring MySQL backups is a vital part of any reliable backup solution. By monitoring the most common disaster recovery metrics, the Recovery Time Objective and the Recovery Point Objective, you can find out if a backup job was successful and produced a usable backup copy. The TwinDB Backup Tool along with Datadog allows monitoring both […]

The post Monitoring MySQL Backups With Datadog and TwinDB Backup Tool appeared first on TwinDB.

Updating/Deleting Rows with ClickHouse (Part 1)

In this post, we’ll look at updating and deleting rows with ClickHouse. It’s the first of two parts.

Update: Part 2 of this post is here.

ClickHouse is fast – blazing fast! It’s quite easy to pick up, and with ProxySQL integrating with existing applications already using MySQL, it’s way less complex than using other analytics options. However, ClickHouse does not support UPDATE/DELETE (yet). That entry barrier can easily dissuade potential users despite the good things I mentioned.

If there is a will, there is a way! We have so far taken advantage of the new feature that supports more granular partitioning strategy (by week, by day or something else). With more …

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Webinar Wednesday, January 10, 2018: Why We’re Excited About MySQL 8.0

Join Percona’s, CEO and Co-Founder, Peter Zaitsev as he presents Why We’re Excited About MySQL 8.0 on Wednesday, January 10, 2018, at 11:00 am PST / 2:00 pm EST (UTC-8).

Experience: Basic

Tags: Developer, DBAs, Operations, Executive, MySQL

There are many great new features in MySQL 8.0, but how exactly can they help your applications? This session takes a practical look at MySQL 8.0 features and improvements. It looks at the bugs, issues and limitations of previous MySQL versions and how MySQL 8.0 addresses them. It will also cover what you can do with MySQL 8.0 that you couldn’t before.

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Setting up ProxySQL 1.4 with MySQL 5.7 Group Replication

There are 3 pillars for a database architecture: Monitoring, Backup / Restore process, High Availability This blog post is about database High Availability; more precisely about one of the best combo of the moment : MySQL 5.7 Group Replication : the only native HA solution for MySQL, it's a Single/Multi-master update everywhere replication plugin for MySQL with built-in automatic distributed recovery, conflict detection and group membership. ProxySQL 1.4 : probably the best proxy for MySQL.

Write Set in MySQL 5.7: Group Replication

In my previous post, I write that Write Set is not only in MySQL 8.0 but also in MySQL 5.7 though a little hidden.  In this post, I describe Write Set in 5.7 and this will bring us in the inner-working of Group Replication.  I am also using this opportunity to explain and show why members of a group can replicate faster than a standard slave.  We will also see the impacts, on Group Replication,

Using ioping to Evaluate Storage Performance for MySQL Workloads

In this blog post, we’ll look at how ioping can be used with other tools to understand and troubleshoot storage performance, specifically as it relates to MySQL workloads.

I recently ran into ioping, a nice little utility by Konstantin Khlebnikov that checks storage latency.  

For me, the main beauty of ioping is its simplicity and familiarity. It takes after the ubiquitous ping tool, but “pings” the storage instead of the network device.

First, let’s talk about what this tool isn’t: it isn’t a benchmark tool to stress load your storage as heavily as possible. For that, you can use iozone or sysbench (among many others). This also isn’t a tool for looking at …

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Common Table Expressions (CTEs) Part 1

Occasionally at conference or a Meetup, someone will approach me and ask me for help with a MySQL problem.  Eight out of ten times their difficulty includes a sub query. "I get an error message about a corrugated or conflabugated sub query or some such,"  they say, desperate for help.  Usually with a bit of fumbling we can get their problem solved.  The problem is not a lack of knowledge for either of us but that sub queries are often hard to write. 

MySQL 8 will be the first version of the most popular database on the web with Common Table Expressions or CTEs.  CTEs are a way to create temporary tables and then use that temporary table for queries. Think of them as easy to write sub queries!

WITH is The Magic WordThe new CTE magic is indicated with the WITH clause.

mysql> WITH myfirstCTE 
AS (SELECT * FROM world.city WHERE …
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Percona Server for MySQL 5.7.20-19 Is Now Available

Percona announces the GA release of Percona Server for MySQL 5.7.20-19 on January 3, 2018. Download the latest version from the Percona web site or the Percona Software Repositories. You can also run Docker containers from the images in the Docker Hub repository.

Based on MySQL 5.7.20, including all the bug fixes in it, Percona Server for MySQL 5.7.20-19 is the current GA release in the Percona Server for MySQL 5.7 series. …

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Row numbering, ranking: how to use LESS user variables in MySQL queries

Happy New Year to everyone!
I published an article about row numbering and ranking with MySQL, here.

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