Query on FromDual GmbH

SQL Query Tuning - Performance

oli.sennhauser@fromdual.com (Oli Sennhauser) — Mon, 05 Oct 2020 16:13:10 +0000

How could the following SQL queries be improved performance wise and otherwise and can you also explain why your change is more optimal?

Creating synthetic data sets for tuning SQL queries

oli.sennhauser@fromdual.com (Oli Sennhauser) — Fri, 02 Oct 2020 16:50:33 +0000

When it comes to SQL Query tuning with customers we often get the slow running SQL query and possibly, in good cases, also the table structure. But very often, for various reasons, we do not get the data.

MySQL single query performance - the truth!

oli.sennhauser@fromdual.com (Oli Sennhauser) — Fri, 13 Dec 2013 17:33:44 +0000

MySQL single query performance - the truth!

As suggested by morgo I did a little test for the same query and the same data-set mentioned in Impact of column types on MySQL JOIN performance but looking into an other dimension: the time (aka MySQL versions).

Impact of column types on MySQL JOIN performance

oli.sennhauser@fromdual.com (Oli Sennhauser) — Wed, 11 Dec 2013 20:12:40 +0000

In our MySQL trainings and consulting engagements we tell our customers always to use the smallest possible data type to get better query performance. Especially for the JOIN columns. This advice is supported as well by the MySQL documentation in the chapter Optimizing Data Types:

Query performance comparison between MariaDB ColumnStore and other Storage Engines

oli.sennhauser@fromdual.com (Oli Sennhauser) — Thu, 03 Jun 2021 15:53:51 +0200

Storage Engines like InnoDB, Aria and MyISAM are Row Stores. They store rows one after the other in blocks or even directly in a single file (MyISAM). On the other hand a Column Store like MariaDB ColumnStore stores all the same attributes (columns) of the rows together in chunks.