Update XXX Set FXXX =  ( Select ①    From ...   Where ②) Where ③

Update里必须包括3个逻辑部分： 

a.) 在①里指明把字段更新为什么值,即新值. 

b.) 在②里指明待更新表和源表需要更新行之间的对应关系 

c.) 在③里指明待更新表有哪些记录需要更新 

注意: 写好updte 语句后需要在ksql中翻译一下,在oracle和db2下可能会多翻译出一些语句(可能包含参数?) ,这样会导致执行时报错: 

Caused exception message is: 索引中丢失  IN 或 OUT 参数:: 3 

比如:

UPDATE T_SD_SaleOrderEntry  SET (FPreReceived, FUnPrereceivedAmount) =            (SELECT T_SD_SaleOrderEntry.FPreReceived + IsNull(rbe.FActualAmt, 0)                  AS FPreReceived,                  T_SD_SaleOrderEntry.FPrepayment - IsNull(rbe.FActualAmt, 0)                  AS FUnPrereceivedAmount           FROM T_CAS_ReceivingBillEntry rbe           WHERE rbe.FSourceBillEntryId = T_SD_SaleOrderEntry.FID AND rbe.FReceivingBillID = "xxxx")  WHERE T_SD_SaleOrderEntry.FID IN            (SELECT soe.FID           FROM T_SD_SaleOrderEntry soe, T_CAS_ReceivingBillEntry rbe           WHERE rbe.FSourceBillEntryId = soe.FID AND rbe.FReceivingBillID = "xxxx")