Book Image

Teradata Cookbook

By : Abhinav Khandelwal, Viswanath Kasi, Rajsekhar Bhamidipati
Book Image

Teradata Cookbook

By: Abhinav Khandelwal, Viswanath Kasi, Rajsekhar Bhamidipati

Overview of this book

Teradata is an enterprise software company that develops and sells its eponymous relational database management system (RDBMS), which is considered to be a leading data warehousing solutions and provides data management solutions for analytics. This book will help you get all the practical information you need for the creation and implementation of your data warehousing solution using Teradata. The book begins with recipes on quickly setting up a development environment so you can work with different types of data structuring and manipulation function. You will tackle all problems related to efficient querying, stored procedure searching, and navigation techniques. Additionally, you’ll master various administrative tasks such as user and security management, workload management, high availability, performance tuning, and monitoring. This book is designed to take you through the best practices of performing the real daily tasks of a Teradata DBA, and will help you tackle any problem you might encounter in the process.
Table of Contents (19 chapters)
Title Page
Dedication
Packt Upsell
Contributors
Preface
Index

Decoding explain


<span>Even though the EXPLAIN plan is in plain English, it is not easy to understand the underlying meaning without understanding the main keywords. At first look, it possibly won't make any sense to you and you may not relate it to the query. We will decode the output into its pieces to carve out the relevant information behind it.

How to do it...

  1. Identify the query for which you want to check the explain.
  2. It is recommended to check the explain of all the queries before executing, as query plans get changed if table demographics are changed.
  3. Hit F6 by selecting the query to get the explain, or write the EXPLAIN keyword before the query and press F5:
Explain
Insert  Into  test01.webclicks 
select * From    au.az_clicks;
  1. The explain plan will be generated in the result set window.

How it works...

English text will be generated, showing the path of the query. Different queries have different keywords. It is the user who needs to understand based on the plan as it is optimized...