Choose a Primary Index | Teradata Vantage - 17.00 - 17.05 - Choosing a Primary Index - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - Database Administration

Product
Advanced SQL Engine
Teradata Database
Release Number
17.00
17.05
Published
June 2020
Language
English (United States)
Last Update
2021-01-22
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Defining the primary index (PI) for a table is the most critical aspect of table design.

The system uses the PI to assign each data row to an Access Module Processor (AMP). A well chosen PI balances the distribution across AMPs and helps optimize the performance of queries that access the table. PIs also enable efficient joins and aggregations.

A query does not use a PI for access unless all columns in the index are in an equality predicate or an IN LIST.

After you identify the PI requirements for a table, you specify the PI as part of the CREATE TABLE statement.