Help Center/ Migration Center/ FAQs/ Big Data Verification/ Why Does a Field in Hive Fail the Sum Verification?
Updated on 2024-10-21 GMT+08:00

Why Does a Field in Hive Fail the Sum Verification?

Symptom

In a big data verification task for Hive, the verification rule was sum, and a double field that stores 1.7976931348623157E308 or -1.7976931348623157E308 failed the verification.

Possible Causes

When the Spark-SQL client is used to execute SQL statements, the returned values of the same command may be different.

This is because in a distributed computing environment, the sequence in which calculations are performed can vary, leading to slight inconsistencies in results. During the processing of values near the maximum limit of the double type (1.7976931348623157E+308), adding even a small value like 2.0 can lead to an overflow, which essentially means the resulting value cannot be represented correctly and often just stays unchanged. It is a quirky but common phenomenon in floating-point arithmetic, due to precision limitations.