MySQL is not only a relational database, but can also be used as a schemaless/NOSQL document store, or a mix of both. This is realized by the JSON datatype, and is useful for any data that is hard to fit in the ”tabular” format of a traditional table.…

In this blog, I’ll look at how to do MySQL point in time recovery (PITR) correctly.

Sometimes we need to restore from a backup, and then replay the transactions that happened after the backup was taken. This is a common procedure in most disaster recovery plans, when for example you accidentally drop a table/database or run an update/delete without the “where” clause and lose data.

The usual way is to get a copy of your binlogs and use mysqlbinlog to replay those transactions. But this approach has many pitfalls that can make the whole PITR process a nightmare. Some examples:

• You need to make sure to run a single mysqlbinlog command with all related binlogs, and pipe them to mysql at once. Otherwise, if binlog.000001 creates a temporary table, and …

MySQL 8.0.1 introduced a work with replication threads mutexes in order to improve performance. In MySQL 8.0.2 the same work was extended, focusing in usability, and revamped how replication deals with disk-full conditions, improving the responsiveness of both monitoring commands and administrative commands such as KILL, as well as making status messages much more precise and helpful.…

Setting up a replication slave is pretty straightforward, yet cumbersome process that needs a lot of attention to detail. Even if at first glance the six steps are simple, together they constitute something that is everything but easy to grasp. What’s Our Solution We decided to fix that. As a result, our very own TwinDB […]

The post How To Setup a Replication Slave With TwinDB Backup Tool appeared first on TwinDB.

Great news! MySQL 8.0.3 is out and it is a release candidate. In the replication team we have been busy working on interesting new enhancements and also doing some clean up. Some of these new features are out in this release.…

Comparing Oracle MySQL Group Replication and Galera Cluster through a probability perpective seems quite interesting. At commit time both use a group certification process that requires network round trips. The required time for these network roundtrips is what will mainly determined the cost of a transaction. Let us try to compute an estimate of the ...continue reading "Probability perspective on MySQL Group replication and Galera Cluster"

In this blog post, we’ll discuss migrating data from encrypted Amazon MySQL RDS to encrypted Amazon Aurora.

One of my customers wanted to migrate from an encrypted MySQL RDS instance to an encrypted Aurora instance. They have a pretty large database, therefore using mysqldump or a similar tool was not suitable for them. They also wanted to setup replication between old MySQL RDS and new Aurora instances.

Spoiler: this is possible without any logical dump.

At first, I checked Amazon’s documentation on encryption and found nothing about this type of …

In this blog post, we’ll look at some of the MySQL high availability solution options.

In the previous post of this series, we looked at the MySQL high availability (HA) solutions that have been around for a long time. I called these solutions “the elders.” Some of these solutions (like replication) are heavily used today and have been improved from release to release of MySQL.

This post focuses on the MySQL high availability solutions that have appeared over the last five years and gained a fair amount of traction in the community. I chose to include this group only two solutions: Galera and RDS Aurora. I’ll use the term “Galera” generically: it covers Galera Cluster, MariaDB Cluster and Percona …

Actually, Mysqlbinlog tools can’t miner mysql binlog exactly correct.

In this post ,a special environment we got may hexadecimal characters what we don’t need.

Read this PDF: Special-code-rollback.pdf

TL;DR: unless you know what you are doing, you should always have a primary key on your tables when replicating in RBR (and maybe even all the time).

TL;DR2: MariaDB 10.1 has an interesting way to protect against missing a primary key (innodb_force_primary_key) but it could be improved.

A few weeks ago, I was called off hours because replication delay on all the slaves from a replication chain