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

How to collect expression stats


With 14.10, we can now collect stats on single table expressions. This improves estimations of the query with expressions; stats can be collected as they were with columns:

COLLECT [SUMMARY] STATISTICS
[USING options]
COLUMN expr [[AS] statistics_name]
[,COLUMN (expr […, expr]) [[AS] statistics_name]]
ON [TEMPORARY] <Table>;

One of the mandatory requirements of the expression stats is that they need to be named. This name, which follows the same rules as other naming database objects, can be used to recollect, help, show, or drop the statistics.

Getting ready

To collect statistics, you need to connect to the Teradata database using Teradata studio or SQLA.

Identify the expression on which statistics need to be collected.

How to do it...

  1. Identify the query on which expression stats need to be collected.
  2. Use the following format to collect statistics:
COLLECT [SUMMARY] STATISTICS
[USING options]
COLUMN expr [[AS] statistics_name]
[,COLUMN (expr […, expr]) [[AS...