Floating Point Expressions - Advanced SQL Engine - Teradata Database

SQL Functions, Expressions, and Predicates

Product
Advanced SQL Engine
Teradata Database
Release Number
17.05
17.00
Published
June 2020
Language
English (United States)
Last Update
2021-01-30
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tpt1555966086716.ditamap
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dita:id
B035-1145
lifecycle
previous
Product Category
Teradata Vantageā„¢

Calculations involving floating point values often produce results that are not what you expect. If you perform a floating point calculation and then compare the results against some expected value, it is unlikely that you get the intended result.

Instead of comparing the results of a floating point calculation, make sure that the result is greater or less than what is needed, with a given error. Here is an example:

   SELECT i, SUM(a) as sum_a, SUM(b) as sum_b
   FROM t1
   GROUP BY i
   HAVING ABS(sum_a - sum_b) > 1E-10;