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SELECT X.WORK_DATE    AS WORK_DATE

          FROM (SELECT SUBSTR( '201111', 1, 6 )||'01' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'02' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'03' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'04' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'05' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'06' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'07' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'08' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'09' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'10' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'11' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'12' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'13' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'14' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'15' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'16' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'17' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'18' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'19' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'20' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'21' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'22' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'23' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'24' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'25' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'26' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'27' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'28' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'29' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'30' WORK_DATE FROM DUAL UNION ALL

                SELECT SUBSTR( '201111', 1, 6 )||'31' WORK_DATE FROM DUAL 

               ) X

         WHERE X.WORK_DATE <=  TRIM(TO_CHAR(LAST_DAY(TO_DATE('20111101','YYYYMMDD')),'YYYYMMDD'))