UPDATE PATIENT_BOOKLET PB SET PB.BOOKLET_NO = (SUBSTRING(PB.BOOKLET_NO FROM 2 FOR CHAR_LENGTH(PB.BOOKLET_NO) - 1)) WHERE (CHAR_LENGTH(PB.BOOKLET_NO) = 8) AND (SUBSTRING(PB.BOOKLET_NO FROM 1 FOR 1) = '0');