ProxySQL Series: Seamless Replication Switchover Using MHA

This is our second blog in the ProxySQL Series ( Blog I MySQL Replication Read-write Split up ). Will cover how to integrate ProxySQL with MHA to handle failover of Database servers. We already have Master - Slave replication setup behind ProxySQL from previous blog [ProxySQL On MySQL Replication] For this setup we have added one more … Continue reading ProxySQL Series: Seamless Replication Switchover Using MHA

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Online Schema Change for Tables with Triggers.

In this post, We will learn how to handle online schema change if the table has triggers. In PXC, an alter can be made directly ( TOI ) on tables with less than a 1G ( by default) , but on a 20GB or 200GB table we need some downtime to do ( RSU ). … Continue reading Online Schema Change for Tables with Triggers.

Investigating a MySQL dead lock

I was involved in one of the development support for MySQL. Here is an interesting case The application needs a Sequence generator as it was not present inbuilt with MySQL ( MariaDB will have it in 10.3 ) they have made sequence generator function with 'select for update' statement. But it tends to cause more locking … Continue reading Investigating a MySQL dead lock

Virtual Columns in MySQL and Use cases.

Introduction: MySQL 5.7 introduces a new feature called virtual/generated column. It is called generated column because the data of this column is computed based on a predefined expression or from other columns. What is Virtual Column ? In general virtual columns appear to be normal table columns, but their values are derived rather than being … Continue reading Virtual Columns in MySQL and Use cases.

MySQL Tablespace Encryption ( TDE )

In this blog we are going to explore about innodb tablespace encryption technique, which will be useful for securing data. In MySQL 5.7, a new feature "Innodb Tablespace Encryption"has been added to protect the data at rest. This is a most awaited feature in security. This encryption supports all file per table tablespaces and it … Continue reading MySQL Tablespace Encryption ( TDE )

Cost-based Optimization in MySQL 5.7

Optimiser is the brain of the RDBMS. Optimiser decides the right access method , algorithms , join order and right index to be used for better execution of the query. This blog is made to shed some lights on Cost based optimiser in MySQL 5.7. The cost or statistics are stored in the data dictionary … Continue reading Cost-based Optimization in MySQL 5.7

InnoDB and Linux mount point.

In this blog we are going to share my recent experience with an issue which we faced during migration between two Ubuntu servers. The activity was pretty simple, the client had bought a new machine with enhanced memory and faster disk, so the data has to be transferred to the new server and live MySQL replication … Continue reading InnoDB and Linux mount point.

InnoDB ‘Linux aio’ returned OS error 0. Cannot continue operation.

We had faced a weird error for one of our client under Emergency MySQL Support, it was a slave server. Client stated that whenever he tries to Start the replication it goes of loop of restarts. We had a sharing session with the client, At first we intended to rebuild the slave with a fresh … Continue reading InnoDB ‘Linux aio’ returned OS error 0. Cannot continue operation.

Estimating records in index range and CPU Spike (MariaDB)

Recently we got paged by CPU spikes on one of our clients slave MySQL ( MariaDB ) server under MyDBOPS Remote DBA Team Support. Our MySQL Engineers started analysing the root cause of the issues and resolved it. This blog provides an overview of the troubleshooting and fix proposed. System Summary : Database server : 10.1.10-MariaDB-log … Continue reading Estimating records in index range and CPU Spike (MariaDB)

Galera Cluster a Walk through ( Presentation)

This presentation is about Galera. Galera is a synchronous high availability clustering solution designed for MySQL. At MyDBOPS we have customers on Galera. They depend on the Galera for their business high availability and read scaling. Handling and troubleshooting a Galera cluster needs more expertise. This presentation is a walk through on Galera Cluster with … Continue reading Galera Cluster a Walk through ( Presentation)