DB2多表關聯UPDATE 語句

 血的教訓換來的，最後一定要加where條件。否則，會將沒有關聯上的數據字段更新成null.

update TM_INS_PROPOSAL TIP
set (Total_Amount,
     Receivable_Busi_Amount,
     Vehicle_Relation,
     Busi_Ins_Code,
     Com_Ins_Code
        )=(select Total_Amount,
                  Receivable_Busi_Amount,
                  Vehicle_Relation,
                  Busi_Ins_Code,
                  Com_Ins_Code
           from TM_INS_PROPOSAL TEMP
           where TIP.ENTITY_CODE = TEMP.ENTITY_CODE
             and TIP.PROPOSAL_CODE = TEMP.PROPOSAL_CODE)
where exists(select 1
             from TM_INS_PROPOSAL TEMP
             WHERE TIP.ENTITY_CODE = TEMP.ENTITY_CODE
               and TIP.PROPOSAL_CODE = TEMP.PROPOSAL_CODE
          )

參考：ORACLE 兩表關聯更新三種方式