16.20 - Overview - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL Operators and User-Defined Functions

Advanced SQL Engine
Teradata Database
Release Number
April 2020
Content Type
Programming Reference
Publication ID
English (United States)
Last Update

Table operators accept a table or table expression as input and generate a table as output. They are a type of user-defined function (UDF). Table operators are used only in the FROM clause of SELECT statements.

Table operators enable a simplified in-database MapReduce-style programming model.

Scalar sub-queries (SSQ) are sub-queries that result in a single value. SSQ is not supported in table operators with multiple ON clauses or ON clauses using PARTITION BY or HASH BY.

You can run table operators on a specific set of AMPs, such as hardware with different connectivity options to access the database. Create a contiguous map to include the nodes, or connectivity options to access the database or different performance characteristics. Then, run a CREATE/REPLACE FUNCTION or CREATE FOREIGN SERVER statement to reference the new contiguous or sparse map.