Null data functions - Amazon IoT SiteWise
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Null data functions

Null data functions handle or manipulate NULL values, which represent the absence of a value. The functions allow you to replace NULLs with other values, check if a value is NULL, or perform operations that handle NULLs in a specific way.

Function

Signature

Description

COALESCE

COALESCE (expression1, expression2, ..., expressionN)

If all expressions evaluate to null, COALESCE returns null. Expressions must be of same type.
Example of a COALESCE function
SELECT COALESCE (l.double_value, 100) AS non_double_value FROM latest_value_time_series AS l LIMIT 1