Uploaded image for project: 'Teiid'
  1. Teiid
  2. TEIID-3743

Multiple Count Distinct Columns Fails for Impala


    • Icon: Bug Bug
    • Resolution: Done
    • Icon: Major Major
    • 8.12
    • 8.11.4
    • Misc. Connectors
    • None

      Teiid Impala translator incorrectly allows multiple count distinct columns, which fails to execute since it is not supported by Impala.

      Per Cloudera documentation:

      By default, Impala only allows a single COUNT(DISTINCT columns) expression in each query.

      To produce the same result as multiple COUNT(DISTINCT) expressions, you can use the following technique for queries involving a single table:

      select v1.c1 result1, v2.c1 result2 from (select count(distinct col1) as c1 from t1) v1 cross join (select count(distinct col2) as c1 from t1) v2;

      The Teiid-Impala translator should ideally rewrite the query as necessary so that the query does not fail executing multiple count distincts against Impala.

            rhn-engineering-shawkins Steven Hawkins
            walla2sl Scott Wallace (Inactive)
            0 Vote for this issue
            2 Start watching this issue