16.20 - Overflow and Numeric Arguments - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL External Routine Programming

Product
Advanced SQL Engine
Teradata Database
Release Number
16.20
Release Date
April 2020
Content Type
Programming Reference
Publication ID
B035-1147-162K
Language
English (United States)

To avoid numeric overflow conditions, the C or C++ function should define a decimal data type as big as it can handle.

If the assignment of the value of an input or output numeric argument would result in a loss of significant digits, a numeric overflow error is reported.

For example, consider a scalar function that takes a DECIMAL(2,0) argument:

CREATE FUNCTION UDF_SMLDEC( p1 DECIMAL(2,0) )
RETURNS DECIMAL(2,0)
LANGUAGE C
NO SQL
PARAMETER STYLE TD_GENERAL
EXTERNAL;

Passing a number with a maximum of two digits is successful:

SELECT UDF_SMLDEC(99);

An attempt to pass a number larger than 99 or smaller than -99 would result in a loss of significant digits.

SELECT UDF_SMLDEC(100);
   
 Failure 2616 Numeric overflow occurred during computation.

Any fractional numeric data that is passed or returned that does not fit as it is being assigned is rounded according to the Teradata rounding rules. For more information on rounding, see “Decimal/Numeric Data Types" in Teradata Vantage™ - Data Types and Literals, B035-1143.