Question

我有这个查询需要2分钟才能执行，即使时间段不长：

SELECT MTI.DeptID,
       ShortEmployees.EmpID,
       ShortEmployees.EmpName1 AS EmpName,
       Sum(CASE
             WHEN (BSR.BSTID = 3
                   AND bli.state IN (12, 13, 14)) THEN -1 * ((BLD.Qty / dbo.Getunitval(BLD.UnitID, BLD.MTID)) * BLD.Price - ((BLD.Qty / dbo.Getunitval(BLD.UnitID, BLD.MTID)) * BLD.Price * BLD.discount * 0.01))
             ELSE ((BLD.Qty / dbo.Getunitval(BLD.UnitID, BLD.MTID)) * BLD.Price - ((BLD.Qty / dbo.Getunitval(BLD.UnitID, BLD.MTID)) * BLD.Price * BLD.discount * 0.01))
           END) AS Total
FROM   BLD
       INNER JOIN BLI
         ON BLD.BLNo = BLI.BLNo
       INNER JOIN BSR
         ON BLI.BLID = BSR.BLID
       INNER JOIN ShortEmployees
         ON BLI.EmpID = ShortEmployees.EmpID
       INNER JOIN MTI
         ON BLD.MTID = MTI.MTID
WHERE  (MTI.DeptID = 'B')
       AND (BLI.BLDate > Cast('2013-01-01 00:00:00' AS DATETIME))
       AND (BLI.BLDate < Cast('2013-01-14 23:59:59' AS DATETIME))
       AND ((BSR.BSTID = 2
             AND bli.state IN (2, 6, 8, 9,
                               10, 12, 18))
             OR (BSR.BSTID = 3
                 AND bli.state IN (12, 13, 14)))
GROUP  BY ShortEmployees.EmpName1,
          ShortEmployees.EmpID,
          MTI.DeptID
ORDER  BY Total DESC

我如何优化它？

MTI：项目信息表。

BLI：票据表。

BLD：Bill详细信息表。

ShortEmployees：Salesmen表。

Answer 1

将条件移动到JOKN ON子句中，可以在进行连接时应用它们，而不是在完成所有连接后进行过滤：

SELECT MTI.DeptID,
       ShortEmployees.EmpID,
       ShortEmployees.EmpName1 AS EmpName,
       Sum(CASE
             WHEN (BSR.BSTID = 3
                   AND bli.state IN (12, 13, 14)) THEN -1 * ((BLD.Qty / dbo.Getunitval(BLD.UnitID, BLD.MTID)) * BLD.Price - ((BLD.Qty / dbo.Getunitval(BLD.UnitID, BLD.MTID)) * BLD.Price * BLD.discount * 0.01))
             ELSE ((BLD.Qty / dbo.Getunitval(BLD.UnitID, BLD.MTID)) * BLD.Price - ((BLD.Qty / dbo.Getunitval(BLD.UnitID, BLD.MTID)) * BLD.Price * BLD.discount * 0.01))
           END) AS Total
FROM BLD
JOIN BLI ON BLD.BLNo = BLI.BLNo
    AND BLI.BLDate BETWEEN Cast('2013-01-01 00:00:00' AS DATETIME)
       AND Cast('2013-01-14 23:59:59' AS DATETIME)
JOIN BSR ON BLI.BLID = BSR.BLID
    AND ((BSR.BSTID = 2
             AND bli.state IN (2, 6, 8, 9, 10, 12, 18)
        OR (BSR.BSTID = 3
             AND bli.state IN (12, 13, 14))
JOIN ShortEmployees ON BLI.EmpID = ShortEmployees.EmpID
JOIN MTI ON BLD.MTID = MTI.MTID
    AND MTI.DeptID = 'B'
GROUP BY ShortEmployees.EmpName1,
    ShortEmployees.EmpID,
    MTI.DeptID
ORDER BY Total DESC

请注意，我将日期范围检查更改为BETWEEN，因为您的查询排除了该期间的第一个和最后一个秒。

我还删除了不必要的括号和缩进

Answer 2

最后，我最终将该查询转换为整个存储过程，差异很大！现在它只需要2秒:)，谢谢大家特别讨厌的喋喋不休;）

Answer 3

要进行其他优化，请在变量中移动Cast（'XXXXX'AS DATETIME）：

DECLARE @dmin DATETIME= Cast('2013-01-01 00:00:00' AS DATETIME);
DECLARE @dmax DATETIME= Cast('2013-01-14 23:59:59' AS DATETIME);
SELECT [blah]
FROM   [blahblah]
WHERE  (MTI.DeptID = 'B')
       AND (BLI.BLDate BETWEEN @dmin AND @dmax)
etc

有没有办法优化此SQL Server查询？

3 个答案: