要求：根据coil_id和passnum检索出多组数据，根据coil_id和passnum求M2-M16的平均值保留三位小数，并写入到新的视图中

创建视图 FEEDBACK_L1

 CREATE VIEW FEEDBACK_L1 AS
SELECT COIL_ID, PASSNUM, ROUND(AVG(M2),3) AS avg_M2, ROUND(AVG(M3),3) AS avg_M3, ROUND(AVG(M4),3) AS avg_M4, ROUND(AVG(M6),3) AS avg_M6 , ROUND(AVG(M7),3) AS avg_M7 , ROUND(AVG(M8),3) AS avg_M8 , ROUND(AVG(M9),3) AS avg_M9 , ROUND(AVG(M10),3) AS avg_M10 , ROUND(AVG(M12),3) AS avg_M12 , ROUND(AVG(M14),3) AS avg_M14 , ROUND(AVG(M15),3) AS avg_M15 , ROUND(AVG(M16),3) AS avg_M16  
FROM ADP_MEAS
GROUP BY COIL_ID,PASSNUM;

结果：在视图FEEDBACK_L1中根据coil_id 和 passnum检索只有一条数据，并且值的来源为上述多组的均值