In this blog, we will discuss about bidirectional replication between two NDB clusters. With this topology, user can do transaction simultaneously from both the clusters on the same database objects.

Let’s create two MySQL NDB Cluster with the following environment, Here, both will be termed as ‘source’ cluster as well as ‘replica’ cluster as we will do replication from both the sides.

• MySQL NDB Cluster version (Latest GA version)
• 1 Management node
• 4 Data nodes
• 2 MySQLDs
• Configuration slots for up to 4 additional API nodes

Replication schema diagram:

                    |-----------S1---------->>----------S3--------------|                   …

This article focuses on the database storage engines for MySQL that ensure appropriate performance and manage SQL operations for multiple table types. The article examines the differences between the most widely used MySQL storage engines. MySQL is the second most popular Relational Database Management Systems (RDBMS) in the world. Countless services and applications have MySQL […]

The post Storage Engines in MySQL appeared first on Devart Blog.

 In the 1990s I spent a few years studying requirements on databases used in 3G telecom networks. The main requirement was centered around three keywords, Latency, Throughput and Availability. In this blog post I will focus on Availability.

If a telecom database is down it means that no phone calls can be made, internet connections will not work and your app on your smartphone will cease to work. So more or less impacting each and everyone's life immediately.

The same requirements on databases now also start to appear in AI applications such as online Fraud detection, self-driving cars, smartphone apps.

Availability is measured in percent and for telecom databases the requirement is to reach 99.9999% availability. One often calls this Class 6 availability where 6 is the number of nines in the availability percentage.

Almost every database …

I found myself explaining the nuances of INSERT statements and whether you should use named or positional notation. While the class was on Zoom, I could imagine the blank stares in the silence of my headphones. Then, I had to remind them about mandatory (NOT NULL constrained) and optional (nullable) columns in tables and how an INSERT statement requires an explicit NULL value for optional columns when the INSERT statement isn’t inserting a value into that column.

Then, I asked if somebody could qualify the different types of INSERT statements; and what would happen if a table with a first_name and last_name column order evolves when a new DBA decides to restructure the table and uses a last_name and first_name column order in the new table structure. Only a couple of the students recalled using a column-list …

Moodle is the world’s most popular learning management system. Moodle is Open Source and of course it’s compatible with the most popular Open Source Database : MySQL !

I’ve already posted an article on how to install Moodle on OCI before we released MySQL Database Service. In this article we will see how to deploy Moodle very easily in OCI and using MDS.

Once again we will use the easiest way to deploy an complete architecture on OCI: Resource Manager.

We will then use a stack I’ve created that is available on GitHub This stack includes Terraform code allowing to deploy different architectures that we can use for Moodle. I’ve tried to cover the main possible architecture directly in the stack. …

About a month ago, I published how you can connect to MySQL with a small form. One suggestion, or lets promote it to a request, from that post was: “Nice, but how do you create a reusable library for the MySQL Connection Dialog box?”

That was a good question but I couldn’t get back until now to write a new blog post. This reusable MySQL connection dialog lets you remove MySQL connection data from the command-line history. This post also shows you how to create and test a Powershell Module.

The first step to create a module requires that you set the proper %PSModulePath% environment variable. If you fail to do that, you can put it into a default PowerShell module location but that’s not too effective for testing. You launch the System Properties dialog and click the Environment …

MySQL is a widely-used open source relational database management system. In this tutorial, we will use one master node to store the cluster's configuration and two data nodes to store the cluster data.

Back in December 2018, when we announced the general availability of Percona Server for MySQL 8.0, we also announced that the TokuDB Storage Engine has been marked as “deprecated” in this release, recommending to use the MyRocks Storage Engine as an alternative. We believe that MyRocks provides similar benefits for the majority of workloads and is better optimized for modern hardware.

Since then, we have continued maintaining the storage engine in the 8.0 release, e.g. by incorporating bug fixes. However, the ongoing amount of …

 Deploy MySQL Enterprise Edition with OCI Market Place Application
In this blog we will look into the process to deploy MySQL Enterprise Edition in to Oracle Cloud Infrastructure.
In this blog we will discuss the below agenda1. Introduction about MySQL EE and OCI Market place
2. Deploy MySQL EE into Oracle Cloud Infrastructure
3. Accessing MySQL database from On-premises.
4. Licensing/Purchase model of using MySQL EE from OCI marketplace
5. Conclusion
IntroductionIf you wanted to run MySQL Enterprise Edition (EE) in Oracle Cloud Compute Instance (VM) then generally what we do is first download the MySQL EE binaries from the oracle website and manually push to the Oracle Cloud Instance where, MySQL EE needed to be installed and follow the steps to get installed.Another approach is going with MySQL EE image from Oracle Cloud Marketplace.It …

To see what queries are sent to MySQL, it’s useful to enable query logging and piping the output to a file or even a table to inspect later. In this [...]

The post How to enable MySQL query logging appeared first on Geeky Hacker.