Use EXPLAIN to Analyze the Usefulness of Secondary Indexes - Analytics Database - Teradata Vantage

SQL Data Definition Language Detailed Topics

Deployment
VantageCloud
VantageCore
Edition
Enterprise
IntelliFlex
VMware
Product
Analytics Database
Teradata Vantage
Release Number
17.20
Published
June 2022
Language
English (United States)
Last Update
2023-07-11
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vuk1628111288877.ditamap
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dita:id
B035-1184
lifecycle
latest
Product Category
Teradata Vantage™

Before a request is processed, the Optimizer estimates comparative costs to determine whether the use of a secondary index offers savings or is plausible. If not, it uses a different access method. You should test the performance of a secondary index before implementing it.

Use the SQL EXPLAIN request modifier to generate a description of the processing sequence to help determine whether a secondary index should be retained. See Teradata Vantage™ - SQL Data Manipulation Language, B035-1146.