ETL: COALESCE

Return the first non-null argument from a list of expressions. Use COALESCE for null handling and providing default values in ETL pipelines.

Description

Returns the first non-NULL argument.

Syntax

COALESCE(expression1, expression2 […,expressionN])

Examples

COALESCE(field1, field2, field3)

Notes

All arguments must be of the same datatype.

Return value datatype

Depends on input data type.

Impact of null value

If all inputs are null, returns null.