Nondeterministic Queries | CREATE FOREIGN TABLE | Teradata Vantage - 17.00 - Queries on External Data are Nondeterministic - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL Data Definition Language Syntax and Examples

Product
Advanced SQL Engine
Teradata Database
Release Number
17.00
Release Date
September 2020
Content Type
Programming Reference
Publication ID
B035-1144-170K
Language
English (United States)

When you create a foreign table or use READ_NOS to read directly from external object storage, you must specify a key prefix as part of the USING...LOCATION parameter to identify specific data (one or more files that match the key prefix). However, the actual data queried in the external storage that correspond to the key prefix is determined when you make a foreign table query. Because data may be added or deleted to the external storage system at any time, identical queries against external storage may yield different results.