SELECT YMFROM, ( CASE WHEN ASCII (YMFROM) BETWEEN 65 AND 122 THEN YMFROM END ) AS YM1, ( CASE WHEN ASCII (YMFROM) < 65 or ASCII (YMFROM) > 122 THEN YMFROM END ) AS YM2 FROM D_BZGFMX ORDER BY YM1 ASC, TO_NUMBER(YM2) ASC
