>SELECT tmp.mcat_code, tmp.mat_code, Mat.mcat_desc, Mat.mat_desc, SUM(tmp.qty) AS qty >FROM (SELECT mcat_code, mat_code, SUM(qty) AS qty > FROM mat_ob > GROUP BY mcat_code, mat_code > UNION > SELECT mcat_code, mat_code, SUM(qty) AS qty > FROM Purchase > GROUP BY mcat_code, mat_code > UNION > SELECT mcat_code, mat_code, SUM((con_qty + wst_qty) * - 1) AS qty > FROM Production > GROUP BY mcat_code, mat_code ) AS tmp INNER JOIN > Mat ON Mat.mcat_code + Mat.mat_code = tmp.mcat_code + tmp.mat_code >GROUP BY tmp.mcat_code, tmp.mat_code, Mat.mcat_desc, Mat.mat_desc >ORDER BY tmp.mcat_code, Mat.mat_desc >>