In MySQL 8.0.0, the Performance Schema can now instrument server errors. There are 5 new summary tables introduced:

mysql> show tables like "%by_error%";
+-------------------------------------------+
| Tables_in_performance_schema (%by_error%) |
+-------------------------------------------+
| events_errors_summary_by_account_by_error |
| events_errors_summary_by_host_by_error    |
| events_errors_summary_by_thread_by_error  |
| events_errors_summary_by_user_by_error    |
| events_errors_summary_global_by_error     |
+-------------------------------------------+
5 rows in set (0.02 sec)

As names suggest, statistics of errors in these tables are aggregated by error.…

If you have deployed databases with high availability before, you will know that a deployment does not always go your way, even though you’ve done it a zillion times. You could spend a full day setting everything up and may still end up with a non-functioning cluster. It is not uncommon to start over, as it’s really hard to figure out what went wrong.

So, deploying a MySQL Galera Cluster with redundant load balancing takes a bit of time. This blog looks at how long time it would take to do it manually vs using ClusterControl to perform the task. For those who have not used it before, ClusterControl is an agentless management and automation software for databases. It supports MySQL (Oracle and Percona server), MariaDB, MongoDB (MongoDB inc. and Percona), and PostgreSQL.

For manual deployment, we’ll be using the popular “Google university” to …

Oracle OpenWorld starts soon and there will be a few sessions on the MySQL Optimizer.   On Monday, I will have my tutorial on how to analyze and tune MySQL queries.  Later in the week Manyi Lu, the MySQL optimizer team manager, will present what was new in the MySQL optimizer 5.7, and also give a sneak peek into the MySQL 8.0 release.  Both of us will together have a presentation  on Common Table Expressions; a new SQL feature in MySQL 8.0.  The details are as follows: 
Monday, Sep 19, 1:45 p.m.  How to Analyze and Tune MySQL Queries for Better Performance [TUT3750]
Oystein Grovlen, Senior Principal Software Engineer, Oracle

…

In this blog post, we’ll look at what MySQL does under the hood to transform NoSQL requests to SQL (and then store them in InnoDB transactional engine) when using the X Plugin.

X Plugin allows MySQL to function as a document store. We don’t need to define any schema or use SQL language while still being a fully ACID database. Sounds like magic – but we know the only thing that magic does is make planes fly!

Alexander already wrote a blog post exploring how the X Plugin works, with some examples. In this post, I am going to show some more query examples and how they are transformed.

I have enabled the slow query …

With the added complexity of growing data volumes and ever changing workloads, database performance tuning is now necessary to maximize resource utilizations and system performance. However, performance tuning is often easier said than done.

Let’s face it, tuning is difficult for a number of reasons. For one thing, it requires a significant amount of expertise in order to understand execution plans, and often update or re-write good SQL. On top of that, tuning is usually very time consuming. There will always be a large volume of SQL statements to sort through, which may lead to uncertainty around which specific statement needs tuning; and given every statement is different, so too is the tuning approach.

As data volumes grow and technology becomes increasingly complex, it is becoming more important to tune databases properly to deliver end-user experience and to lower infrastructure costs. Performance tuning can help database …

Dear MySQL Community,

We have something we want to show you that we are very excited about. Stay tuned until Monday to learn all about it on the MySQL Server Blog.

And yes, the title of this blog post already might give you a big hint. But psssst! Let’s wait till Monday…

Hi all, it is time again to do another preview release of MySQL Group Replication, the plugin that brings multi-master update everywhere support to MySQL, like we described in the Hello World post.

We are very proud to present the eighth preview release of MySQL Group Replication plugin, based on MySQL Server 5.7.15.…

When it comes to “decision time” about which type of MySQL HA (high-availability) solution to implement, and how to architect the solution, many questions come to mind. The most important questions are:

• “What are the best tools to provide HA and Load Balancing?”
• “Should I be deploying this proxy tool on my application servers or on a standalone server?”.

Ultimately, the best tool really depends on the needs of your application and your environment. You might already be using specific tools such as Consul or MHA, or you might be looking to implement tools that provide richer features. The dilemma of deploying a proxy instance per application host versus a standalone proxy instance is usually a trade-off between “a less effective load balancing algorithm” or “a single point of failure.” Neither are desirable, but there are ways to implement a solution that balances all …

In MySQL 8.0 we are improving the Performance Schema to support indexes. This increases the flexibility and ease of use of using performance_schema, as a number of monitoring queries will see a dramatic speed up in performance.

Background

Since it’s initial launch in MySQL 5.5, the Performance Schema has grown to 93 tables, with some of these exposing a lot of data.…

I'm not a huge fan of the InnoDB FULLTEXT feature and I admit I wasn't too keen to play with it in the past. Apparently, the feeling is mutual and so FULLTEXT issues haven't popped up in too many projects I worked on... until last week.

This post describes the troubleshooting process of a FULLTEXT cache performance issue. Quite inconspicuous at the beginning, it proved to be a lot of fun in the end.

Ready, Set, GDB!
Background It all started with a generic performance issue report unrelated to FULLTEXT indexing. The issue, as described in the report, was:

1. The server performs acceptably for a few days.
2. After a certain amount of time, DML performance suddenly drops and remains low until the server is rebooted.
3. Reboot restores original performance, which again only lasts for a few days.

The situation was resulting in DML latency degradation during normal OLTP …