Question

我正在尝试从MS Access中构建的两个单独的sql查询的结果中获取AVERAGE。第一个sql查询提取最大记录：

SELECT DISTINCTROW Sheet1.Tx_Date, Sheet1.LName, Sheet1.Patient_Name, Sheet1.MRN, 
  Max(Sheet1.) AS [Max Of FEV1_ACT], 
  Max(Sheet1.FEF_25_75_ACT) AS [Max Of FEF_25_75_ACT]
FROM Sheet1
GROUP BY Sheet1.Tx_Date, Sheet1.LName, Sheet1.Patient_Name, Sheet1.MRN;

第二个sql查询提取第二大记录：

SELECT Sheet1.MRN, Sheet1.Patient_Name, Sheet1.Lname, 
  Max(Sheet1.FEV1_ACT) AS 2ndLrgOfFEV1_ACT, 
  Max(Sheet1.FEF_25_75_ACT) AS 2ndLrgOfFEF_25_75_ACT
FROM Sheet1
WHERE (((Sheet1.FEV1_ACT)<(SELECT MAX( FEV1_ACT )
                 FROM Sheet1 )))
GROUP BY Sheet1.MRN, Sheet1.Patient_Name, Sheet1.Lname;

这两个查询效果很好，我只需要帮助将这两个查询的结果AVERAGE合并为一个。感谢。

Answer 1

联合这些查询并平均记录集

select avg(select field from table1 union select field from table2)

Answer 2

怎么样

SELECT Avg(FEV1_ACT) FROM
    (SELECT Top 2 FEV1_ACT FROM Sheet1 ORDER BY FEV1_ACT DESC)

获取两个SQL Access查询的AVERAGE

2 个答案: