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Displaying posts with tag: MySQL Cluster (reset)
NDB Parallel Query, part 4

In this part we will discuss how NDB batch handling works. Query execution of
complex SQL queries means that more rows can be delivered than the receiver is
capable of receiving. This means that we need to create a data flow from the
producer where the data resides and the query executor in the MySQL Server.

The MySQL Server uses a record where the storage engine have to copy the result
row into the record. This means that the storage of batches of rows is taken
care of by the storage engine.

When NDB performs a range scan it will decide on the possible parallelism before
the scan is started. The NDB API have to allocate enough memory to ensure that
we have memory prepared to receive the rows as they arrive in a flow of result
rows from the data nodes. It is possible to set batch size of hundreds and even
thousands of rows for a query.

The …

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NDB Parallel Query, part 3

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 …

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Testing MySQL NDB Cluster with dbdeployer

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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 …

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Installing WordPress 5 on ZEIT Now with MySQL Hosting

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 …

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MySQL Cluster Manager 1.4.7 released!


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.…

Reminder: MySQL User Group NL and Madrid MySQL User Group Meetups presenting Scaling MySQL this week (Monday/Thursday)

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)

The post Reminder: MySQL User Group NL and Madrid MySQL User Group Meetups presenting Scaling MySQL this week (Monday/Thursday)

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2018-11-15: Announcing: Scaling MySQL with TiDB, Vitess and MySQL Cluster at Madrid MySQL Users Group

[ 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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MySQL NDB Cluster: Never Install a Management Node on the Same Host as a Data Node

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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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Monitoring NDBCluster Copying Alter Progress

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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 …

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Global Read-Scaling using Continuent Clustering

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 …
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Showing entries 11 to 20 of 497
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