Rather than making an assignment that results in a loss of significant digits, Vantage reports an overflow error.
Avoid numeric overflow in a C or C++ function by defining the largest decimal data type the function can handle.
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 is an error.
SELECT UDF_SMLDEC(100);
Result:
Failure 2616 Numeric overflow occurred during computation.
Fractional numeric data passed or returned that does not fit during assignment is rounded according to the Teradata rounding rules. See Teradata Vantage™ - Data Types and Literals, B035-1143.