16.20 - Computation of INTEGER or DECIMAL Values - Teradata Database

Teradata Vantageā„¢ - SQL Functions, Expressions, and Predicates

Advanced SQL Engine
Teradata Database
March 2019
Programming Reference

An AVG of a DECIMAL or INTEGER value may overflow if the individual values are very large or if there is a large number of values.

If this occurs, change the AVG call to include a CAST function that converts the DECIMAL or INTEGER values to REAL as shown in the following example:

   AVG(CAST(value AS REAL) )

Casting the values as REAL before averaging causes a slight loss in precision.

The type of the result is REAL in either case, so the only effect of the CAST is to accept a slight loss of precision where a result might not otherwise be available at all.

If x is an integer, AVG does not display a fractional value. A fractional value may be obtained by casting the value as DECIMAL, for example the following CAST to DECIMAL.

   CAST(AVG(value) AS DECIMAL(9,2))