Is there a way to use something like Oracle's "IGNORE NULLS" with the last_value() analytic function (or similar)? I want to fill all the nulls in a column with the last value in that column that was non-null. In Oracle I can do something like the below. How can I implement this in Impala? I need to forward fill the null values if possible, and if the partition begins with null, I'd like to backfill from the first non-null value.   -- Oracle sample query -- select user, date, val, case when val is null then last_value(val ignore nulls) over (partition by user order by date) else val end as new_val ... View more