The followin sql (valid in Oracle 11) is not accepted by the parser. <b>select col1, min(col2) KEEP (DENSE_RANK FIRST ORDER BY col3), col4 from table1 group by col5 order by col3</b> see: https://docs.oracle.com/cd/B19306_01/server.102/b14200/functions056.htm#i1000901