请问这条语句如何写才能提高效率？

Question

不要用not in
用 
...
AND NOT exists
 (SELECT 1
 FROM W_MGoodsLocation
 WHERE W_MGoodsLocation.DCCode = ‘gstrDCCode '
 AND W_MGoodsLocation.ConsignorCode ='strConC' 
 and W_MGoodsLocation.DCGoodsCode = C_MGoods.DCGoodsCode )

Answer 1

not in比较慢，建议使用外连接SELECT  C_MGoods.DCGoodsCode,C_MGoods.GoodsPShortName, C_MGoods.LoginDate
 FROM C_MGoods，W_MGoodsLocation
 WHERE C_MGoods.ConsignorCode ='strConC' 
 AND W_MGoodsLocation.ConsignorCode ='strConC'
 AND W_MGoodsLocation.ConsignorCode ='strConC'
 AND C_MGoods.DCGoodsCode = W_MGoodsLocation.DCGoodsCode(+)
 AND W_MGoodsLocation.DCGoodsCode is null
 W_MGoodsLocation.DCCode = ‘gstrDCCode '
 ORDER BY C_MGoods.DCGoodsCode