Overview The Skinny

Part of the power of Tungsten Clustering for MySQL / MariaDB is its intelligent MySQL Proxy, known as the Tungsten Connector. The Tungsten Connector has built-in read-write splitting capabilities, and it is also possible to configure different algorithms which select the appropriate slave (i.e. Round-Robin or Lowest-Latency).

The Question Recently, a customer asked us:

How do we best share the load between read-only slaves? Currently, there appears to be an imbalance, with most of the read-only queries reaching just one slave. What may we do to improve this situation?

This customer noticed that a couple of long …

Without a doubt, the MySQL database is the most popular database that already exists. There are countless tricks, options, and functions available for MySQL developers. The developers often are surrounded by many technical and detailed contents which can easily distract them from MySQL's big picture. The problem is that they lack a checklist of all the essential techniques to master. I have developed and normalized many advance MySQL databases (along with IT consulting), which motivated me to write this article. What follows are 15 essential tricks or things that any serious MySQL developer should know.

When somebody wants to migrate from a single MySQL instance to a full HA solution using MySQL InnoDB Cluster, the best solution to reduce the downtime is to use asynchronous replication and switch database only once at a certain point in time when everything is ready. This is almost what I explained already in this post.

The most difficult part was related to the provisioning of the existing data to the new cluster members. A backup (physical or logical) was required. It should have been restored on every nodes and we had to be sure to not mess up with the GTIDs.

This is not more the case since MySQL 8.0.17 ! Now we can use the CLONE plugin to start the cluster provisioning too.

The current situation

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Percona is glad to announce the release of Percona XtraBackup 8.0.7 on August 7, 2019. You can download it from our download site and apt and yum repositories.

Percona XtraBackup enables MySQL backups without blocking user queries, making it ideal for companies with large data sets and mission-critical applications that cannot tolerate long periods of downtime. Offered free as an open source solution, it …

This tutorial explains how you can grant privileges on a database in MySQL. It will introduce you all the steps beginning from connecting to MySQL and then accessing the MySQL commands to set the desired level of privileges. So, if you wish to grant or update the privileges in MySQL, first you should connect to […]

The post Grant Privileges on a Database in MySQL appeared first on TechBeamers.

This tutorial explains how you can grant privileges on a database in MySQL. It will introduce you all the steps beginning from connecting to MySQL and then accessing the MySQL commands to set the desired level of privileges. So, if you wish to grant or update the privileges in MySQL, first you should connect to […]

The post Grant Privileges on a Database in MySQL appeared first on TechBeamers.

This tutorial explains how to use the MySQL FROM_UNIXTIME() function with the help of examples. By using it, you can convert or display a UNIX_TIMESTAMP value to a timestamp. The output format is either YYYY-MM-DD-HH-MM-SS or YYYYMMDDHHMMSS, which depends on the calling context of the function. It means that FROM_UNIXTIME() would return a string for […]

The post MySQL FROM_UNIXTIME() Function appeared first on TechBeamers.

This tutorial explains how to use the MySQL FROM_UNIXTIME() function with the help of examples. By using it, you can convert or display a UNIX_TIMESTAMP value to a timestamp. The output format is either YYYY-MM-DD-HH-MM-SS or YYYYMMDDHHMMSS, which depends on the calling context of the function. It means that FROM_UNIXTIME() would return a string for […]

The post MySQL FROM_UNIXTIME() Function appeared first on TechBeamers.

The Replicator is a critical piece of the Tungsten Clustering solution for MySQL / MariaDB, as well as its own stand-alone data replication product. Automatic recovery is a feature that enables the Replicator to go back online in the event of a transient failure. In this blog we discuss how to enable Automatic Recovery. For more information about Auto-Recovery, please click here to visit the online documentation page.

The Question Recently, a customer asked us:

We see that the replicators receive a transaction which has a deadlock error in it:

pendingError : Event application failed: seqno=82880882 fragno=0 message=java.sql.SQLTransactionRollbackException: Deadlock found when trying to get lock; try restarting transaction

If one performs a service online, it comes back online without issue and continues …

Migrations between different environments are uncommon in database world. Migrations from one provider to another one. Moving from one datacenter to another. All of this happens on a regular basis. Organisations search for expense reduction, better flexibility and velocity. Those who owned their datacenter look forward to switch to one of the cloud providers where they can benefit from better scalability and handling capacity changes. Migrations touch all elements of the database environment - databases themselves but also the proxy and caching layer. Moving databases around is tricky but it is also hard to manage multiple proxy instances, ensuring that the configuration is in sync across all of them.

In this blog post we will take a look at challenges related to one particular piece of migration - migrating ProxySQL proxy layer from …