MySQL Cluster Tutorial - cdn.oreillystatic.com

This would allow us to make a much simpler query:
SELECT uid, location FROM subscribers WHERE uid = 3
Primary Keys and Unique Indexes
You should define a Primary Key for every MySQL Cluster table. If you don’t, one will be
created automatically, but that’s considered bad practice.
Both the Primary Key and Unique Indexes will use data and index memory, unless you give
the USE HASH option when you create the table. This way, only the hash part will be created
and no data memory will be consumed. Updating data will be faster, less data memory will
be used, but queries doing range scans might be slower.
Historical Data
Remove redundant even quicker within MySQL. Only the data that is hot when you have
lots of changes and new records coming.
Disk-Based Tables
Tables can be created so non-indexed fields are going to disk instead of memory. This will
allow you to store much more data in MySQL Cluster, but you have to also consider some
possible performance penalty.
One of the reasons why MySQL Cluster is storing in memory is to compensate for the
possible network latency. Hard drives could possibly add more latency.
You will need to create a ‘logfile group’, and ‘tablespaces’. We are not covering this in the
tutorial, but the MySQL Manual has a nice example will get you going. Note that you might
need to configure your MySQL Cluster to get it actually working well.
Some external links:
http://dev.mysql.com/doc/refman/5.1/en/mysql-cluster-disk-data.html
http://johanandersson.blogspot.com/2008/12/disk-data-summary.html
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