Hi, I'm puzzled by two queries returning duplicate rows: 1) SELECT LIST('Hi') FROM RDB$DATABASE UNION SELECT LIST('Hi') FROM RDB$DATABASE
2) WITH TMP(DuplicateRows) AS (SELECT LIST('Hi') FROM RDB$DATABASE UNION SELECT LIST('Hi') FROM RDB$DATABASE) SELECT DISTINCT DuplicateRows FROM TMP I was certain UNION (as opposed to UNION ALL) should remove duplicates and the same with DISTINCT. To get the latter query to return one row, GROUP BY can be added, I don't know how to make the first query return only one row. Is this a Firebird error, and if so, is it a new one or one fixed in newer versions? Set