SQL CONCAT_WS Function Example | CONCAT_WS Method In SQL is today’s topic. The SQL CONCAT_WS function is used to join two or more expressions separated by a separator. It takes up to 255 input strings which are further joined by a function. If we want to perform the join operation, CONCAT requires at least 2 strings. If it is provided with only 1 string, it will raise the error.

SQL CONCAT_WS Function

If any non-character string values are passed into the function, it will be implicitly converted to the strings before concatenating.

If NULL is added to the function, it converts it into the empty string with VARCHAR (1).

See the following syntax.

SELECT CONCAT_WS (separator, expression1, expression2, expression3…)

Parameters Separator

We just wrapped up what was a very exciting OOW 2019 - San Francisco for MySQL.  Our MySQL track included 29 sessions, a keynote with 2 customer testimonials (Mercari and WePay), 1 tutorial, 1 Hands-on lab, 1 Birds of a Feather, and our always fun and enjoyable MySQL Community Reception.  

A BIG Thank You to the companies who came to share their experience and testimonial about how MySQL helps scale their company such as Facebook, JP Morgan Chase WePay, Credorax, Mercari, Zuora, and more.

Our focus this year: SECURITY.  With 3,800 breaches and over 4 Billion Records Stolen in just H1 2019, securing data has become a priority for any business. The first part of the keynote covers the new security features from Oracle and MySQL implemented in our latest version of the Enterprise Edition.

Other highlights for MySQL:

• MySQL 8.0,  fastest adoption of any version with over 26% …

In a previous post, I showed you how to compile Percona Mysql 5.7 on Raspberry PI 3. Now, I’ll show you how to compile and run the latest version of Percona XtraDB Cluster 5.7.26.

We will need at least 3 RaspberryPi 3 boards, and I recommend you use an external SSD drive to compile and use as MySQL’s “datadir” to avoid the stalls associated with the microSD card, which will cause PXC to run slow.

In this post, we are going to run many OS commands and configure PXC. I recommend having minimal knowledge about PXC and Linux commands.

How to install CentOS

Download the centos image from this link …

Overview The Skinny

In this blog post we explore various options for performance tuning MySQL server for better slave replication performance.

A Tungsten Cluster relies upon the Tungsten Replicator to move events from the master node to the slaves. Once the event has been transferred to the slave as THL on disk, the slave applier will then attempt to write it to the database. The Replicator can only apply events as fast as MySQL allows. If the MySQL server is somehow slow or blocking, then the Replicator will be as well.

A properly-tuned database server in addition to infrastructure and SysAdmin best practices will go quite a long way towards high-performance slave apply.

The Question Recently, a customer asked us:

During one of our load tests, we had a peak of 60k writes/min, averaging …

My first talk is a tutorial Testing like a boss: Deploy and Test Complex Topologies With a Single Command, scheduled at Percona Live Europe in Amsterdam on September 30th at 13:30.

My second talk is Amazing sandboxes with dbdeployer scheduled on October 1st at 11:00. It is the same topic as the tutorial, but covers a narrow set of features, all in the *amazing* category.

The tutorial introduces a challenging topic, because when people hear testing, they imagine a troop of monkeys fiddling with a keyboard and a mouse, endlessly repeating a boring task. What I want to show is that testing is a creative activity and, with the right tools and mindset, it could be exciting and rewarding. During my work as a quality assurance engineer, I have always seen a boring task as an opportunity to automate. …

This week you can find our MySQL & MySQL Community experts at following shows:

• db tech showcase, Tokyo, Japan, September 25-27, 2019

  • MySQL team as Silver sponsor will have a booth in the expo area and in total 5 speaking slots related to MySQL as follows: 
    • Two User Case Studies of MySQL
    • Two Technical Sessions by MySQL User Community members (MyNA)
    • MySQL Server, MySQL Workbench and MySQL Shell by MySQL GBU 
  • Please watch organizers' website for more details.
• …

We’re happy to announce that our white paper ‘Tungsten Clustering – Benefits & Configurations’ for MySQL, MariaDB and Percona Server is available to read on our website.

Tungsten Clustering is a one-of-a-kind software solution that provides clustering, disaster recovery and high availability for MySQL, MariaDB & Percona Server databases.

It allows enterprises running business-critical database applications to cost-effectively achieve continuous operations on a global scale with:

• Commercial-grade high availability (HA)
• Geographically redundant disaster recovery (DR)
• Global operations with geographically distributed multi-master

…

If you have been around MySQL for any length of time, you are probably aware that choosing the correct data types and optimizing your schema are actually important tasks.  A few years back at Percona Live 2016, I gave an introductory talk on schema review and optimization. Here’s the video:

I was thinking about that talk in the context of some of my current clients.  Though I had worked on extremely large database deployments during my earlier tenure at Percona, it was often more of an outlier.  Now, working as a Technical Account Manager with our largest clients, it is much more common.

The Fundamental Problem

I’d like to expand my thoughts on the “choosing the smallest data type you can” principle from my 2016 slides through the lens of a few of my 2019 …

Percona Live is always a great opportunity to learn from the best and brightest in the open-source database community. This time, Percona Live Europe is being held at the Hilton Amsterdam Airport Schiphol, The Netherlands from September 30 to October 2, 2019.

Pythian will be present, as has been the case for the past few years, with some of our technical experts speaking on a variety of subjects and technologies.

Feel free to ping any of us during the conference breaks or community events, as we’ll be happy to answer any questions you have about anything open source, cloud, or data-related.

Here are some sessions you won’t want to miss:

Wednesday, October 2

9:00 AM – …

I’ve been away from writing blog posts — the last one was more than two years ago. I decided to write one on this topic, however; I found out that implementing a queue was harder than it should be (in my opinion). Although Magento’s shenanigans don’t really surprise me anymore, the complexity of getting a simple queue up and running caught me (and my estimate) by surprise. There’s a few other blog posts on this topic already, but I found they don’t quite get into the nitty gritty that you potentially can get stuck on.

You might be the first person to mention simple and async in one sentence.

— Fooman (@foomanNZ) July 8, 2019

That said, today I’m going to write about how to create a queue that does additional order processing using Magento 2 and MySQL only — without RabbitMQ.

Why …