using a UDF in a Windows function

[BradSheridan]

I have created a UDF using:

%sql

CREATE OR REPLACE FUNCTION f_timestamp_max()....

And I've confirmed it works with:

%sql

select f_timestamp_max()

But when I try to use it in a Window function (lead over partition), I get:

AnalysisException: Using SQL function 'default.f_timestamp_max' in Window is not supported.

Can anyone share a way of being able to do this?

[Debayan]

Hi, As of now, Spark SQL supports three kinds of window functions: ranking functions. analytic functions. aggregate functions. Please refer: https://docs.databricks.com/sql/language-manual/sql-ref-window-functions.html#parameters