CASE语句

UPDATE cdssa SET cnno = CASE WHEN (cnno IS NULL OR TRIM(cnno)='') THEN '${CNNO}' else cnno end,stdt = CASE WHEN (stdt IS NULL OR TRIM(stdt)='') THEN '${STDT}' else stdt end,eddt = CASE WHEN (eddt IS NULL OR TRIM(eddt)='') THEN '${EDDT}' else eddt endWHERE cuno = '${CUNO}';