3. The computer program product of claim 1 , further comprising program instructions to: determine whether the partitioning columns of the GROUP BY operation quantified by the right side of the OUTER JOIN operation are the same as the partitioning columns of the GROUP BY operation quantified by the left side of the OUTER JOIN operation; and wherein said OUTER JOIN operation is removed from the query only in response to determining that the partitioning columns of the GROUP BY operation quantified by the right side of the OUTER JOIN operation are the same as the partitioning columns of the GROUP BY operation quantified by the left side of the OUTER JOIN operation.
4. The computer program product of claim 3 , wherein the OUTER JOIN operation is one of a FULL OUTER JOIN, a LEFT OUTER JOIN or a RIGHT OUTER JOIN.