Certain guidelines apply when you use window functions on the Spark engine.
Consider the following rules and guidelines when you define window functions in a transformation:
Specify a constant integer as the offset argument in a window function.
Specify a default argument that is the same data type as the input value.
You cannot specify a default argument that contains complex data type or a SYSTIMESTAMP argument.
To use the LEAD and LAG window functions, you must configure partition and order keys in the windowing properties.
To use an aggregate function as a window function in an Expression transformation, you must configure a frame specification in the windowing properties.