In the previous part we showed how NDB will parallelise a
simple
2-way join query from TPC-H. In this part we will describe
how
the pushdown of joins to a storage engine works in the MySQL
Server.
First a quick introduction to how a SQL engine handles a
query.
The query normally goes through 5 different phases:
1) Receive query on the client connection
2) Query parsing
3) Query optimisation
4) Query execution
5) Send result of query on client connection
The result of 1) is a text string that contains the SQL query
to
execute. In this simplistic view of the SQL engine we will
ignore
any such things as prepared statements and other things making
the
model more complex.
The text string is parsed by 2) into a data structure that
represents
the query in objects that match concepts in the SQL engine.
Query …
A great way to install MySQL when you need to do quick tests is to use a sandbox tool. This allows you to perform all the installation steps with a single command making the whole process very simple, and it allows for automation of the test. Giuseppe Maxia (also known as the Data Charmer, @datacharmer on Twitter) has for many years maintained sandbox tools for MySQL, first with MySQL Sandbox and now with dbdeployer.
One of the most recent features of dbdeployer is the support for MySQL NDB Cluster. In this blog, I will take …
[Read more]Want to deploy WordPress 5.0 on the Now platform by ZEIT? Our friends over at ZEIT’s Now global serverless deployment platform whipped up a great tutorial for WordPress5-on-Now using cheap MySQL hosting instances from ScaleGrid. With such strong interest in this installation, we decided to write up the steps to configure your MySQL database on the ScaleGrid side to get you up and running ever faster with WordPress on Now.
Leave your comments: https://t.co/exuBzSHkHM
@now/wordpress summary:
◆ λ size = 13mb
◆ Just needs `wp-config.php`
◆ All static assets output directly to CDN …
MySQL Cluster Manager 1.4.7 is now available for download from My
Oracle Support.
Overview
MCM 1.4.7 continues to improve MySQL Cluster Manager by adding
some sought after features – and some important bugfixes.
The 1.4.7 release bundles MySQL Cluster 7.6.8.…
This is a quick reminder that this week there are 2 MySQL User Group Meetings (Amsterdam and Madrid) where we will be talking about Scaling MySQL. Guest speaker will be Morgan Tocker from PingCap who will talk about TiDB. More information: MySQL User Group NL meetup taking place on Monday (presenting: Morgan, Daniël and Simon) … Continue reading Reminder: MySQL User Group NL and Madrid MySQL User Group Meetups presenting Scaling MySQL this week (Monday/Thursday)
[Read more][ English ] – texto en español abajo We’re pleased to announce the next Madrid MySQL Users Group meetup which will take place on the 15th of November at 19:00. Sign up details can be found here. There’ll also be a similar meetup in Amsterdam on the 12th November hosted by a colleague. Details here. … Continue reading 2018-11-15: Announcing: Scaling MySQL with TiDB, Vitess and MySQL Cluster at Madrid MySQL Users Group
The post 2018-11-15: Announcing: Scaling MySQL with TiDB, Vitess and MySQL Cluster at Madrid MySQL Users Group first appeared on Simon J Mudd's …
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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: …[Read more]
MySQL NDB Cluster has great support for online (inplace) schema
changes, but it is still sometimes necessary to perform an
offline (copying) ALTER TABLE. These are relatively
expensive to make as the entire table is copied into a new table
which eventually replace the old table.
One example where a copying ALTER TABLE is required
is when upgrading from MySQL NDB Cluster 7.2 or earlier to MySQL
NDB Cluster 7.3 or later. The format used for temporal columns
changed between these version (corresponding to MySQL Server 5.5
to 5.6). In order to take advantage of the new temporal format, a
table rebuild is required.
Note: Support for the old temporal format has been removed in MySQL 8.0. So, you must …
[Read more]Did you know that Continuent Clustering supports having clusters at multiple sites world-wide with either active-active or active-passive replication meshing them together?
Not only that, but we support a flexible hybrid model that allows for a blended architecture using any combination of node types. So mix-and-match your highly available database layer on bare metal, Amazon Web Services (AWS), Azure, Google Cloud, VMware, etc.
In this article we will discuss using the Active/Passive model to scale reads worldwide.
The model is simple: select one site as the Primary where all writes will happen. The rest of the sites will pull events as quickly as possible over the WAN and make the data available to all local clients. This means your application gets the best of both worlds:
- Simple deployment with no application changes needed. All writes …
Welcome to the third part of this series. I’m glad you’re still reading, as hopefully this means you find this subject interesting at least. Previously we presented the first two components of MySQL InnoDB Cluster: Group Replication and MySQL Router and now we will discuss the last component, MySQL Shell.
MySQL Shell
This is the last component in the cluster and I love it. Oracle have created this tool to centralize cluster management, providing a friendly, command-line based user interface.
The tool can be defined as an advanced MySQL shell, which is much more powerful than the well known MySQL client. With the capacity to work …
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