17.05 - Guidelines for Coding Noncorrelated Subqueries - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL Data Manipulation Language

Product
Advanced SQL Engine
Teradata Database
Release Number
17.05
Published
January 2021
Language
English (United States)
Last Update
2021-01-22
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To perform a subquery as an noncorrelated subquery and not as a correlated subquery, observe the following guidelines.
  • For each main and subquery you code, ensure that its scope is local by specifying a FROM clause that includes all the tables it references.
  • Instead of specifying join operations in the main queries of DELETE and UPDATE statements, restrict them to subqueries.