Sparse Join Indexes - Advanced SQL Engine - Teradata Database

SQL Fundamentals

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Published
July 2021
Language
English (United States)
Last Update
2021-07-28
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B035-1141
lifecycle
previous
Product Category
Teradata Vantageā„¢

You can create join indexes that limit the number of rows in the index to only those that are accessed when, for example, a frequently run query references only a small, well known subset of the rows of a large base table. By using a constant expression to filter the rows included in the join index, you can create what is known as a sparse index.

Any join index, whether simple or aggregate, multitable or single-table, can be sparse.

To create a sparse index, use the WHERE clause in the CREATE JOIN INDEX statement.