I was recently asked a question by mail about MySQL Lossless Semi-Synchronous Replication. As I think the answer could benefit many people, I am answering it in a blog post. The answer brings us to the internals of transaction committing, of semi-synchronous replication, of MySQL (server) crash recovery, and of storage engine (InnoDB) crash recovery. I am also debunking some misconceptions that I have often seen and heard repeated by many. Let’s start by stating one of those misconceptions.

One of those misconceptions is the following (this is NOT true): semi-synchronous enabled slaves are always the most up-to-date slaves (again, this is NOT true). If you hear it yourself, then please call people out on it to avoid this spreading more. Even if some slaves have semi-synchronous replication disabled (I will use semi-sync for …

We are happy to announce that MySQL got an opportunity to be part of the Oracle Developer Community LAD Tour 2018 on the last minute notice. The event is hold on Aug 24 @ Mexico City, Mexico you will can - among other interesting talks - also to find a MySQL talk given by the local Sales Consultant, Manuel Contreras. Manuel will be talking about “MySQL 8.0”.

We are looking forward to seeing & talking to you there!

In this post I’ll give to you the steps to compile Percona Server for MySQL 5.7.22 in Raspberry Pi 3. Why? Well because in general this little computer is cheap, has low power consumption, and is great to use as a test machine for developers.

By default Raspbian OS includes very few versions of MySQL to install

$ apt-cache search mysql | grep server
...
mariadb-server-10.0 - MariaDB database server binaries
mariadb-server-10.1 - MariaDB database server binaries
mariadb-server-core-10.0 - MariaDB database core server files
mariadb-server-core-10.1 - MariaDB database core server files
mysql-server - MySQL database server binaries and system database setup [transitional] (5.5)
...

If you want to install MySQL or MariaDB on an ARM architecture using official pre-built binaries, you are limited to those distributions and versions.

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This tutorial demands a service restart since some flags here presented can not be dynamically changed

What is GTID and why do I need it? Directly from the MySQL documentation (excerpt taken as is with different jargons than used here, for master/slave we are using primary/replica):

A global transaction identifier (GTID) is a unique identifier created and associated with each transaction committed on the server of origin (the master). This identifier is unique not only to the server on which it originated, but is unique across all servers in a given replication topology.

GTID assignment distinguishes between client transactions, which are committed on the master, and replicated transactions, which are reproduced on a slave. When a client transaction is committed …

Please join Percona’s CEO, Peter Zaitsev as he presents MySQL vs MongoDB – Choosing the Right Technology for Your Application on Thursday, August 23, 2018, at 10:30 AM PDT (UTC-7) / 1:30 PM EDT (UTC-4).

Register Now

Are you considering to adopt the most popular open source relational database or the most popular open source NoSQL database? Which one is right for your particular application?

In this presentation, we will look into advantages and disadvantages of both and examine the applications where MySQL or MongoDB are the most appropriate choice.

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Galera Cluster is the leading high availability solution for MySQL and MariaDB. We are always looking for bright and driven people who have a passion for technology, especially for database replication and clustering. If you are interested in challenging work, being part of a innovative team and world’s leading MySQL clustering company-then Codership is right place for you!  This is a remote job.

Job Description and Responsibilities

• Write Galera Cluster technical marketing material (blogs, white papers, benchmarks)
• Prepare presentations and present at webinars and conferences
• Be active in social media channels and forums
• Consult customers for Galera Cluster best practices
• Pre-sales support
• Interface with the development team to provide user feedback
• Assist in writing Galera documentation

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In this example i will show you simple way to create table column sorting from database using php mysql we will do it sorting column by clicking column header with php and mysql in table It is a very basic example for php starter to create column sort ascending descending order by click on colu

In this example i will show you simple way to create table column sorting from database using php mysql we will do it sorting column by clicking column header with php and mysql in table It is a very basic example for php starter to create column sort ascending descending order by click on colu

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In MySQL NDB Cluster, the management node (ndb_mgmd) is a lightweight process that among other things handles the configuration of the cluster. Since it is lightweight. It can be tempting to install it with one of the other nodes. However, if you want a high-availability setup, you should never install it on the same host as a data node (ndbd or ndbmtd). If you do that, it can cause a total cluster outage where the cluster could otherwise have survived.

The first sign of trouble occurs when you start the management nodes. The following warning is printed to standard output:

2018-08-22 18:04:14 [MgmtSrvr] WARNING  -- at line 46: Cluster configuration warning: …

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Apress have been kind enough to invite me to write a blog in connection with my recently released book MySQL Connector/Python Revealed. I chose to write an introduction of MySQL Connector/Python including three examples illustrating the APIs and the difference between querying SQL tables and a JSON document store.

You can read the whole post at Apress’ blog.

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