nullIf
nullIf
compares two expressions. If they are equal, the function
returns null. If they are not equal, the function returns the first
expression.
Syntax
nullIf(
expression1
,expression2
)
Arguments
nullIf
takes two expressions as arguments.
- expression
-
The expression can be numeric, datetime, or string. It can be a field name, a literal value, or another function.
Return type
String
Example
The following example returns nulls if the reason for a shipment delay is unknown.
nullIf(delayReason, 'unknown')
The following are the given field values.
delayReason ============ unknown back ordered weather delay
For these field values, the following values are returned.
(null) back ordered weather delay