I have used many tools starting with MMM to be able to manage MySQL replication clusters. Some of the tools need more tools and complex HA solutions such as Pacemaker and Corosync, or Zookeeper. While other tools do not do the failover well which leaves the slaves in an inconsistent state, MMM would be an example. And I must say that of all the tools I love MySQL Master HA (MHA) the most. MHA is a great tool to manage MySQL replication clusters for the purpose of HA. The most important thing about MHA is that it tries to take all the necessary steps to do a MySQL master failover in a way that provides as much data consistency as possible. The slave promotion also tends to be very quick, on average I have seen it take 10 to 15 seconds. It is also very easy to deploy unlike some of the other complex HA solutions. I would highly recommend reading about the architecture of MHA on its wiki: https://code.google.com/p/mysql-master-ha/wiki/Architecture Why …
[Read more]This Log Buffer Edition covers various useful tips and tricks from blogs for Oracle, SQL Server and MySQL.
Oracle:
- pstack(or thread stack) for Windows to diagnose Firefox high CPU usage
- With the ever-changing browser landscape, we needed to make some tough decisions as to which browsers and versions are going to be deemed “supported” for Oracle Application Express. There isn’t enough time and money to support all browsers and all versions, each with different bugs and varying levels of support of standards.
- Are you effectively using Java SE 8 streams …
The MySQL team has been maintaining a MySQL image on Docker. They have been listening to requests from the community and reacting quickly. So far, they have fixed two bugs that I reported and introduced a feature request that I suggested to make the server more secure.
Thanks, folks!
My latest request was about password management in a MySQL container. I have mentioned in previous posts the compatibility problems introduced by MySQL 5.7 security enhancements. Let me recap the main issues here:
MySQL is secure by default.
The recommended method to install MySQL is mysqld
--initialize, which will generate a random password that the DBA will
then use to access the …
I have used many tools starting with MMM to be able to manage
MySQL replication clusters. Some of the tools need more tools and
complex HA solutions such as Pacemaker and Corosync, or
Zookeeper. While other tools do not do the failover well which
leaves the slaves in an inconsistent state, MMM would be an
example.
And I must say that of all the tools I love MySQL Master HA (MHA)
the most. MHA is a great tool to manage MySQL replication
clusters for the purpose of HA. The most important thing about
MHA is that it tries to take all the necessary steps to do a
MySQL master failover in a way that provides as much data
consistency as possible. The slave promotion also tends to be
very quick, on average I have seen it take 10 to 15 seconds. It
is also very easy to deploy unlike some of the other complex HA
solutions.
I would highly recommend reading about the architecture of MHA on its wiki: …
[Read more]In a recent post the MySQL product managers asked the community for feedback about proposed new defaults. One of the proposals is to make log-slave-updates on by default.
There are other important options that require some debate. They all look reasonable to me. This one, instead, which implies funnelling the replication events in a slave to its binary log, is questionable.
Let's start for the reason why it is a good idea. The scenario in which it makes sense is when you want a slave to be a master of one or more slaves. This is a common scenario in many cases where you need …
[Read more]Ready for another post in the EXPLAIN FORMAT=JSON is Cool series! Great! This post will discuss how to see all the information that is contained in optimized queries with
UNION
using the
union_result
and
query_specifications
commands.
When optimizing complicated queries with
UNION
, it is easy to get lost in the regular
EXPLAIN
output trying to identify which part of the output belongs to each part of the
UNION
.
Let’s consider the following example:
mysql> explain
-> select emp_no, last_name, 'low_salary' from employees
-> where emp_no in (select emp_no from salaries
-> where salary < (select avg(salary) …[Read more]
The MariaDB project is pleased to announce the immediate availability of MariaDB 10.1.11. See the release notes and changelog for details on this release. Download MariaDB 10.1.11 Release Notes Changelog What is MariaDB 10.1? MariaDB APT and YUM Repository Configuration Generator Thanks, and enjoy MariaDB!
The post MariaDB 10.1.11 now available appeared first on MariaDB.org.
Percona is glad to announce the new release of Percona XtraDB Cluster 5.6 on January 29, 2016. Binaries are available from the downloads area or from our software repositories.
Percona XtraDB Cluster 5.6.28-25.14 is now the current release, based on the following:
[Read more]Yes, it has been a while since my last post. Still in the midst of MySQL ecosystem, and enjoying it tremendously. I thought I would make this post as it relates to a topic that has some varied results in the online world, and I would like to kick start this blog again. We'll see how that goes... :)
MySQL has been able to harness the potential of more powerful (CPU) and larger (
In the MySQL world, we’re used to playing in the MySQL Sandbox. It allows us to deploy a testing replication environment in seconds, without a great deal of effort or navigating multiple virtual machines. It is a tool that we couldn’t live without in Support.
In this post I am going to walk through the different ways we have to deploy a MongoDB replica/sharding set test in a similar way. It is important to mention that this is not intended for production, but to be used for troubleshooting, learning or just playing around with replication.
Replica Set regression test’s diagnostic commands
MongoDB includes a .js that allows us to deploy a replication set from the MongoDB’s shell. Just run the following:
# mongo --nodb …[Read more]