In this post we show how to use the mysql-server Docker image for local development. We first introduce a simple example app that starts up and tries to connect to a given db until successful. We then show how to start containers for multiple MySQL versions and use our example app to connect to them. […]
In this blog post, we’ll look at a solving Sudoku using MySQL 8.0 recursive common table expression.
Vadim was recently having a little Saturday morning fun solving Sudoku using MySQL 8. The whole idea comes from SQLite, where Richard Hipp has come up with some outlandish recursive query examples — WITH clause.
The SQLite query:
WITH RECURSIVE input(sud) AS ( VALUES('53..7....6..195....98....6.8...6...34..8.3..17...2...6.6....28....419..5....8..79') ), digits(z, lp) AS ( VALUES('1', 1) UNION ALL SELECT CAST(lp+1 AS TEXT), lp+1 FROM digits WHERE lp<9 ), x(s, ind) AS ( SELECT sud, instr(sud, '.') FROM input UNION ALL SELECT …[Read more]
Thank you everyone who attended our webinar on “What’s new in Monyog & Roadmap update”.
In this webinar, Shree Nair, Product Manager at Webyog demonstrated the various features introduced in Monyog since v8.1.0. Moreover, Shree showcased a number of scenarios on how to align the new features per use case.
Here’s the complete video for all those who couldn’t attend the webinar.
Summary of the top features discussed in the webinar: Set distinct email distribution list for warning and critical alerts
Monyog allows users to specify separate recipients depending on the state of the alert, i.e., critical, warning or others. The critical alerts such as server going down, slave not running can be sent to the on-call DBAs while other warning alerts can be sent to members of the team.
Trend Graph Analysis
Trend graph analysis makes it easier to compare the state and …
[Read more]Percona announces the release of Percona Toolkit 3.0.5 on November 21, 2017.
Percona Toolkit is a collection of advanced command-line tools that perform a variety of MySQL and MongoDB server and system tasks too difficult or complex for DBAs to perform manually. Percona Toolkit, like all Percona software, is free and open source.
You download Percona Toolkit packages from the web site or install from official repositories.
This release includes the following changes:
New Features:
- PT-216: The …
Overview
ProxySQL had been adopted as solution for HA in place of HAProxy
in Percona PXC package.
The new solution has a lot of advantages and provide an
unbelievable flexibility we did not had before. But when
talking about HA and PXC there was still a gap.
As already discussed in my previous article “ProxySQL and Percona
XtraDB Cluster (Galera) Integration”(https://www.percona.com/blog/2016/09/15/proxysql-percona-cluster-galera-integration/),
ProxySQL is working great when using multi-master approach, but
trying to have it in single Node writer, was not possible unless
using creative (nice way to say wrong) solutions like what I was
covering in “ProxySQL and PXC using Replication HostGroup” in the
same article.
In the following months, I had few emails and requests from …
Our pleasure to announce that MySQL Community team is present at the RoOUG event with two MySQL talks. Please find the details below:
- Date: December 12, 2017
- Place: Bucharest, Romania (Oracle Romania, Floreasca Park, ground floor GF13)
- Agenda:
- 18:30 – 18:40 – Registration
- 18:40 – 19:30 – MySQL InnoDB Cluster – speaker Frédéric Descamps, MySQL Community Manager
- 19:30 – 19:45 – Coffee Break
- 19:45 – 20:35 – MySQL Document Store – speaker Frédéric Descamps, MySQL Community Manager
- 20:35 – 21:00 – Q&A, networking
- URL (more information and registration): …
In this blog post, we’ll look at some of the facets of InnoDB page compression.
Somebody recently asked me about the best way to handle JSON data compression in MySQL. I took a quick look at InnoDB page compression and wanted to share my findings.
There is also some great material on this topic that was prepared and presented by Yura Sorokin at Percona Live Europe 2017: https://www.percona.com/live/e17/sessions/percona-xtradb-compressed-columns-with-dictionaries-an-alternative-to-innodb-table-compression. Yura also implemented …
[Read more]tl;dr: The source is at github.com/Preetam/explain-analyzer and you can try it out here.
I read Performance Impacts of Data Volume a few weeks ago on “Use The Index, Luke!” and found the whole workflow really fascinating. Here’s the first paragraph on that page:
The amount of data stored in a database has a great impact on its performance. It is usually accepted that a query becomes slower with additional data in the database. But how great is the performance impact if the data volume doubles? And how can we improve this ratio? These are the key questions when discussing database scalability.
I was thinking about this and how query EXPLAINs from a test environment can help …
[Read more]You can take down a MySQL database in multiple ways. Some obvious ways are to shut down the host, pull out the power cable, or hard kill the mysqld process with SIGKILL to simulate an unclean MySQL shutdown behaviour. But there are also less subtle ways to deliberately crash your MySQL server, and then see what kind of chain reaction it triggers. Why would you want to do this? Failure and recovery can have many corner cases, and understanding them can help reduce the element of surprise when things happen in production. Ideally, you would want to simulate failures in a controlled environment, and then design and test database failover procedures.
There are several areas in MySQL that we can tackle, depending on how you want it to fail or crash. You can corrupt the tablespace, overflow the MySQL buffers and caches, limit the resources to starve the server, and also mess around with permissions. In this blog post, we are going to show you some …
[Read more]Join Percona Chief Evangelist Colin Charles as he covers happenings, gives pointers and provides musings on the open source database community.
So we have announced the call for presentations for Percona Live Santa Clara 2018. Please send your submissions in!
As you probably already know, we have been expanding the content to be more than just MySQL and MongoDB. It really does include more open source databases: the whole of 2016 had a “time series” theme to it, and we of course love to have more PostgreSQL content (there have been tracks dedicated to PostgreSQL for sometime now). I found this one comment interesting recently, from John Arundel, “If you’re going to learn one database really well, make it Postgres.” I have been noticing newer developers jump on the …
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