… or what I should keep in mind in case of disaster

To retrieve and maintain in SQL format the definition of all tables in a database, is a best practice that we all should adopt. To have that under version control is also another best practice to keep in mind.

While doing that may seem redundant, it can become a life saver in several situations. From the need to review what has historically changed in a table, to knowing who changed what and why… to when you need to recover your data and have your beloved MySQL instance not start…

But let’s be honest, only a few do the right thing, and even fewer keep that information up to date. Given that’s the case, what can we do when we have the need to discover/recover the table structure?

From the beginning, MySQL has used some external files to describe its internal structure.

For instance, if I have a schema named windmills and a table …

Quickly Add a Node to an InnoDB Cluster or Group Replication (Shutterstock)

In this blog, we’ll look at how to quickly add a node to an InnoDB Cluster or Group Replication using Percona XtraBackup.

Adding nodes to a Group Replication cluster can be easy (documented here), but it only works if the existing nodes have retained all the binary logs since the creation of the cluster. Obviously, this is possible if you create a new cluster from scratch. The nodes rotate old logs after some time, however. Technically, if the

gtid_purged

 set is non-empty, it means you will need another method to add a new node to a cluster. You also …

When deciding on your backup strategy, one of the key components for Point In Time Recovery (PITR) will be the binary logs. Thankfully, the mysqlbinlog command allows you to easily take binary log backups, including those that would otherwise be encrypted on disk using encrypt_binlog=ON.

When

mysqlbinlog

  is used with

--raw --read-from-remote-server --stop-never --verify-binlog-checksum

  then it will retrieve binary logs from whichever master it is pointed to, and store …

In this blog post, I’ll look at point-in-time recovery (PITR) options for MySQL, MariaDB and Percona Server for MySQL.

It is a common good practice to extend data safety by having additional measures apart from regular data backups, such as delayed slaves and binary log backups. These two options provide the ability to restore the data to any given point in time, or just revert from some bad accidents. These methods have their limitations of course: delayed slaves only help if a deadly mistake is noticed fast enough, while full point-in-time recovery (PITR) requires the last full backup and binary …

In this blog post, I’ll look at how to execute a MySQL single table Point-In-Time Recovery.

I recently wrote a blog post describing a different way of doing Point-In-Time Recovery (PITR). If you want to know the step by step, please visit the mentioned blog post. Here is a quick summary of the approach:

1. Restore the backup on the desired server
2. Create a fake master
3. Copy all relevant binlogs to the fake master
4. Configure server from the first step as a slave from a fake master

In addition to the above steps, there is a similar approach …

Join Percona’s, Technical Services Manager, Jervin Real as he presents Lock, Stock and Backup: Data Guaranteed on Wednesday, August 16, 2017 at 7:00 am PDT / 10:00 am EDT (UTC-7).

Reserve Your Spot

Backups are crucial in a world where data is digital and uptime is revenue. Environments are no longer bound to traditional data centers, and span multiple cloud providers and many heterogeneous environments. We need bulletproof backups and impeccable recovery processes. This talk aims to answer …

Data corruption! It can happen. Maybe because of a bug or storage problem that you didn’t expect, or MySQL crashes when a page checksum’s result is different from what it expected. Either way, corrupted data can and does occur. What do you do then?

Let’s look at the following example and see what can be done when you face this situation.

We have some valuable data:

> select * from t limit 4;
+---+--------+
| i | c      |
+---+--------+
| 1 | Miguel |
| 2 | Angel  |
| 3 | Miguel |
| 4 | Angel  |
+---+--------+
> select count(*) from t;
+----------+
| count(*) |
+----------+
|  2097152 |
+----------+

One day the query you usually run fails and your application stops working. Even worse, it causes the crash already mentioned:

> select * from t where i=2097151;
ERROR 2006 (HY000): MySQL server has gone away

Usually this is the point when panic starts. The error log shows: …

January 23, 2014 By Severalnines

Thanks to everyone who attended this week’s webinar; if you missed the sessions or would like to watch the webinar again and browse through the slides, they are now available online.

Special thanks to Seppo Jaakola from Codership, the creators of Galera Cluster, for walking us through the various scenarios of Galera recovery. 

Webinar topics discussed: 

• Redundancy models for Galera, NDB and MongoDB / TokuMX
• Failover & Recovery (Automatic vs Manual)
• Zooming into Galera recovery procedures
• Split brains in multi-datacenter setups

Watch the replay:

…