Go in-depth on how NULLs and Compression are managed in a Teradata system.

Looking first at the Row Format structure and Table Headers, we will discuss where and how NULLs and Compression values are stored. Then we’ll cover how Presence Bits are populated based on both single value compression and multi-value compression along with NULLs. Examples of each type of scenario (Not Null and Compress, Nullable and not Compress, Nullable and Compress, etc.) along with their Presence bits. Later on, we’ll show how tables can be drastically reduced in size with NOT NULL and Compression attributes by doing a BEFORE and AFTER scenario using standard SQL queries to see how much space can be saved on a 15,000 row table. Finally, the presentation covers the Rules for Compression, data types and their space requirements and some best practices. If you want to shave 25-30% off your disk space, increase performance and improve I/O reads, this is the presentation for you.

Key Points:

  • How the TD Row format and Table Header supports Compression

  • How multi-value compression on values and NULLs are handled via Presence bits

  • How much storage space can be saved depending on Data types

Presenter: Mark Ott, Teradata Instructor - Teradata Corporation

This course is offered by the Teradata Education Network. To enroll online, click the Training URL link below to go to the TEN site and Log in. If you're not a member click browse, select your region, and search on the Course Number. Or to enroll by phone, call the Enrollment Center at 1-937-242-4460. Note: You must be a member to register for a course.
Course number:39395
Training URL:http://www.teradata.com/t/ten/
Format:Recorded webcast
Credit hours:1.00