O'Reilly logo

Tera-Tom's 1000 Page e-Book on Teradata Architecture and SQL, 2nd Edition by Tom Coffing, William Coffing

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Chapter 11 - Secondary Indexes

“People can have the Model T in any color – so long as it's black.”

- Henry Ford

Creating a Unique Secondary Index (USI)

images

We created a Unique Secondary Index (USI) on the column Emp_No named idxname.

What is in a Unique Secondary Index (USI) Subtable?

images

Inside the secondary index subtable is the column Emp_No (USI Column). Then, there is the corresponding Row-ID of the real Primary Index of the table. The USI subtable's Primary Index is Emp_No, and it is hashed and has a Row-ID like a normal table.

A Unique Secondary ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required