Hi! I was trying out window functions in SparkSql (using hive context) and I noticed that while this <https://issues.apache.org/jira/browse/TAJO-919?jql=text%20~%20%22lag%20window%22> mentions that *lead* is implemented as an aggregate operator, it seems not to be the case.
I am using the following configuration: Query : SELECT lead(max(`expenses`)) FROM `table` GROUP BY `customerId` Spark Version: 10.4 SparkSql Version: 1.5.1 I am using the standard example of (`customerId`, `expenses`) scheme where each customer has multiple values for expenses (though I am setting age as Double and not Int as I am trying out maths functions). *java.lang.NullPointerException at org.apache.hadoop.hive.ql.udf.generic.GenericUDFLeadLag.evaluate(GenericUDFLeadLag.java:57)* The entire error stack can be found here <http://pastebin.com/jTRR4Ubx>. Can someone confirm if this is an actual issue or some oversight on my part? Thanks!
