The aliases work for me in the following query similar to yours. However, I am using latest master branch and running directly through sqlline command, not through Tableau. Can you confirm what Drill version you are using and check if you can repro the behavior through sqlline ? If so, you should file a JIRA.
select o_custkey as x, date_add(to_date(o_orderdate), 1) as y from cp.`tpch/orders.parquet` where o_orderkey < 10 group by o_custkey, date_add(to_date(o_orderdate), 1) limit 2; +------+-------------+ | x | y | +------+-------------+ | 370 | 1996-01-03 | | 781 | 1996-12-02 | +------+-------------+ On Mon, Dec 21, 2015 at 2:18 AM, Petri Lehtonen <[email protected]> wrote: > Hi all, > > I'm using Tableau with MapR Drill ODBC drivers. I have successfully set > up the drivers and am able to query the data from our source which is > basically parquet files. All seems well as long as I'm using all rows from > the source but when I try to limit the size of the results by grouping and > rolling up the data I came across something that feels like a bug: > > When I use any functions that return dates and add a group by to my query, > the column alias in the underlying sql won't show up in the resultset. > > Plain select from the source works: > > SELECT > valid_from as valid_from_raw, > date_add(to_date(valid_from),1)as valid_from_to_date > FROM > dw.`/directory/parquet-file` > WHERE > valid_from = '1356991200000' > > ---------------+--------------------- > valid_from_raw | valid_from_to_date > ---------------+--------------------- > 1356991200000 | 2013-01-01 > ---------------+--------------------- > > When you add GROUP BY to the SQL, Drill looses the original column alias > and replaces it with it's internal variable or something similar ($f1..n): > > SELECT > valid_from as valid_from_raw, > date_add(to_date(valid_from),1) as valid_from_to_date > FROM > dw.`/directory/parquet-file` > WHERE > valid_from = '1356991200000' > GROUP BY > valid_from as valid_from_raw, > date_add(to_date(valid_from),1) > > ---------------+------------- > valid_from_raw | $f1 > ---------------+------------- > 1356991200000 | 2013-01-01 > ---------------+------------- > > And naturally this creates a problem with Tableau which is mapping the > column aliases from the initial SQL and fails to find the corresponding > aliases from the resultset. Only way to get this working is to use $f0..n > column aliases in the original query and rename them in Tableau... > Something that one definitely shouldn't do. I'd appreciate if anyone has a > solution or a more solid workaround. > > Thanks, > Petri > >
