15.00 - 15.10 - Identity Columns - Teradata Database

Teradata Database Introduction to Teradata

Product
Teradata Database
Release Number
15.00
15.10
Content Type
User Guide
Publication ID
B035-1091-151K
Language
English (United States)
Last Update
2018-09-25

Identity columns are columns that have unique values for every row in the table. Because those values confer uniqueness on every row, the system can use the values to identify each row in a table. When a column is defined as an identity column, Teradata Database automatically generates a unique numeric value for the column in every row that is added to the table.

Identity columns can be used to generate unique values for UPI, USI, and primary key columns. However, creating a UPI from combinations of frequently queried columns is preferable to adding identity columns to tables to serve this function.

For more information about indexes, see “Teradata Database Indexes” on page 109.