The latest from the MySQL community

Introduction

Recently I have been involved in an effort to convert MySQL databases from a utf8 character set to utf8mb4. As a part of this effort, my team evaluated which collations would be best for facilitating a broad range of multi-lingual support.

There have been many recent posts in the MySQL community about better unicode collation support in MySQL 8 such as from the MySQL Server Team’s blog at Oracle, who have also done a good job of showing us how newer collations based on UTF8 9.0.0 will properly group and sort characters according to their case and inheritance. As the title of the latter post suggests, the “devil is” indeed “in the details”.

There is also the matter of the …

Following are the few best practices and basic commands for MySQL Administration.

MySQL Access and credential security

shell> mysql -u testuser -pMyP@ss0rd
mysql: [Warning] Using a password on the command line interface can be insecure.

By looking at OS cmd’s history using history cmd other os users can see/get MySQL user password easily. It always good to not use a password on the command line interface. Another option for securing password while automating MySQL scripts is a use of mysql_config_editor. For more info on this check out my blog post about credential security.

Consider of having following implementation for Strong access policy.

• use of  validate_password plugin for a strong password policy.
• Limit …

In this blog post, we’ll look at the performance of SST data transfer using encryption.

In my previous post, we reviewed SST data transfer in an unsecured environment. Now let’s take a closer look at a setup with encrypted network connections between the donor and joiner nodes.

The base setup is the same as the previous time:

• Database server: Percona XtraDB Cluster 5.7 on donor node
• Database: sysbench database – 100 tables 4M rows each (total ~122GB)
• Network: donor/joiner hosts are connected with dedicated 10Gbit LAN
• Hardware: donor/joiner hosts – boxes with 28 Cores+HT/RAM 256GB/Samsung SSD 850/Ubuntu 16.04

The setup details for the encryption aspects in our testing:

• Cryptography libraries: openssl-1.0.2, …

This post is just following up my previous blog post which describes how to setup 3-nodes MariaDB Galera Cluster with MySQL-Sandbox on single server.

Today, I’ll try to explain how we can setup MariaDB MaxScale over the Galera Cluster. Before I move ahead, I would like to explain about MaxScale little bit.

MariaDB MaxScale is a database proxy that enables horizontal database scaling while maintaining a fast response to client applications. You can implement MaxScale on either MySQL Replication or Galera cluster. With MySQL Replication, you can either use Read/Write Splitting or Connection routing and same with Galera Cluster. You can get more information here about this product.

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In the previous post, we discussed how to verify that MySQL Replication is in good shape. We also looked at some of the typical problems. In this post, we will have a look at some more issues that you might see when dealing with MySQL replication.

Missing or Duplicated Entries

This is something which should not happen, yet it happens very often - a situation in which an SQL statement executed on the master succeeds but the same statement executed on one of slaves fails. Main reason is slave drift - something (usually errant transactions but also other issues or bugs in the replication) causes the slave to differ from its master. For example, a row which existed on the master does not exist on a …

One of the most interesting features introduced in MySQL 8.0 is roles or the ability of defining a set of privileges as a named role and then granting that set to one or more users. The main benefits are more clarity of privileges and ease of administration. Using roles we can assign the same set of privileges to several users, and eventually modify or revoke all privileges at once.

Roles in a nutshell

Looking at the manual, we see that using roles is a matter of several steps.

(1) Create a role. The statement is similar to CREATE USER though the effects are slightly different (we will see it in more detail later on.)

mysql …

This blog shares some column store database benchmark results, and compares the query performance of MariaDB ColumnStore v. 1.0.7 (based on InfiniDB), Clickhouse and Apache Spark.

I’ve already written about ClickHouse (Column Store database).

The purpose of the benchmark is to see how these three solutions work on a single big server, with many CPU cores and large amounts of RAM. Both systems are massively parallel (MPP) database systems, so they should use many cores for SELECT queries.

For the benchmarks, I chose …

One of the services our database engineers provide is adding users to MySQL. We have some nice Chef recipes, so all I have to do is update a few files, including adding in the MySQL password hash.

Now, when I added myself, I just logged into MySQL and generated a password hash. But when my SRE (systems reliability engineer) colleague needed to generate a password, he did not have a MySQL system he could login to.

The good news is it’s easy to generate a MySQL password hash. The MySQL password hash is simply a SHA1 hash of a SHA1 hash, with * at the beginning. Which means you do not need a MySQL database to create a MySQL password hash – all you need is a programming language that has a SHA1 function (well, and a concatenate function).

And I found it, of course, on this post at StackExchange (http://unix.stackexchange.com/a/234592/217471). So you don’t have to click through, here is what it says – and I have …

As we saw earlier, it might be challenging for companies to move their data out of RDS for MySQL. In the first part of this blog, we showed you how to set up your target environment on EC2 and insert a proxy layer (ProxySQL) between your applications and RDS. In this second part, we will show you how to do the actual migration of data to your own server, and then redirect your applications to the new database instance without downtime.

Copying data out of RDS Related resources  MySQL in the Cloud - Online Migration from Amazon RDS to EC2 instance (part 1) …

In our previous blog, we saw how easy it is to get started with RDS for MySQL. It is a convenient way to deploy and use MySQL, without worrying about operational overhead. The tradeoff though is reduced control, as users are entirely reliant on Amazon staff in case of poor performance or operational anomalies. No access to the data directory or physical backups makes it hard to move data out of RDS. This can be a major problem if your database outgrows RDS, and you decide to migrate to another platform. This two-part blog shows you how to do an online migration from RDS to your own MySQL server.

We’ll be using EC2 to run our own MySQL Server. It can be a first step for more complex migrations to your own private datacenters. EC2 gives you access to your data so xtrabackup can be used. EC2 also allows you to setup SSH tunnels and it removes …