我知道要求在这个SQL语句中快速制作一些东西是一个很高的命令，但是如果有人可以看看并且可能建议我如何优化它，我会很感激？
以下查询是由ASP NET脚本生成的（所以我不只是在其中硬编码值）。虽然我为了可读性而“解包”了第一个SELECT语句：
WITH
valDiff0 AS (SELECT datediff(second,
CASE
WHEN '2011-06-06 00:00:00' < [inTime] THEN [inTime]
ELSE '2011-06-06 00:00:00'
END,
CASE
WHEN isdate([outTime]) = 1 THEN
CASE
WHEN '2011-06-06 23:59:59' > [outTime] THEN [outTime]
ELSE '2011-06-06 23:59:59'
END
ELSE
CASE
WHEN '2011-06-06 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800
ELSE '2011-06-06 23:59:59'
END
END)
AS v1 FROM [dbo].[Info] WHERE
[cName] LIKE 'T%'
AND [b] <> 0
AND CONVERT(INT, [evt]) & 7 = 4
AND isdate([inTime]) = 1
AND [inTime] <= '2011-06-06 23:59:59'
AND [outTime] >= '2011-06-06 00:00:00'),
valDiff1 AS (
SELECT datediff(second, CASE WHEN '2011-06-07 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-07 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-07 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-07 23:59:59' END else case WHEN '2011-06-07 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-07 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-07 23:59:59' AND [outTime] >= '2011-06-07 00:00:00'),
valDiff2 AS (SELECT datediff(second,CASE WHEN '2011-06-08 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-08 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-08 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-08 23:59:59' END else case WHEN '2011-06-08 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-08 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-08 23:59:59' AND [outTime] >= '2011-06-08 00:00:00'),
valDiff3 AS (SELECT datediff(second,CASE WHEN '2011-06-09 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-09 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-09 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-09 23:59:59' END else case WHEN '2011-06-09 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-09 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-09 23:59:59' AND [outTime] >= '2011-06-09 00:00:00'),
valDiff4 AS (SELECT datediff(second,CASE WHEN '2011-06-10 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-10 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-10 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-10 23:59:59' END else case WHEN '2011-06-10 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-10 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-10 23:59:59' AND [outTime] >= '2011-06-10 00:00:00'),
valDiff5 AS (SELECT datediff(second,CASE WHEN '2011-06-11 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-11 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-11 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-11 23:59:59' END else case WHEN '2011-06-11 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-11 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-11 23:59:59' AND [outTime] >= '2011-06-11 00:00:00'),
valDiff6 AS (SELECT datediff(second,CASE WHEN '2011-06-12 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-12 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-12 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-12 23:59:59' END else case WHEN '2011-06-12 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-12 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-12 23:59:59' AND [outTime] >= '2011-06-12 00:00:00'),
valDiff7 AS (SELECT datediff(second,CASE WHEN '2011-06-13 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-13 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-13 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-13 23:59:59' END else case WHEN '2011-06-13 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-13 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-13 23:59:59' AND [outTime] >= '2011-06-13 00:00:00'),
valDiff8 AS (SELECT datediff(second,CASE WHEN '2011-06-14 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-14 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-14 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-14 23:59:59' END else case WHEN '2011-06-14 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-14 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-14 23:59:59' AND [outTime] >= '2011-06-14 00:00:00'),
valDiff9 AS (SELECT datediff(second,CASE WHEN '2011-06-15 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-15 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-15 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-15 23:59:59' END else case WHEN '2011-06-15 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-15 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-15 23:59:59' AND [outTime] >= '2011-06-15 00:00:00'),
valDiff10 AS (SELECT datediff(second,CASE WHEN '2011-06-16 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-16 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-16 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-16 23:59:59' END else case WHEN '2011-06-16 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-16 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-16 23:59:59' AND [outTime] >= '2011-06-16 00:00:00'),
valDiff11 AS (SELECT datediff(second,CASE WHEN '2011-06-17 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-17 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-17 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-17 23:59:59' END else case WHEN '2011-06-17 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-17 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-17 23:59:59' AND [outTime] >= '2011-06-17 00:00:00'),
valDiff12 AS (SELECT datediff(second,CASE WHEN '2011-06-18 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-18 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-18 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-18 23:59:59' END else case WHEN '2011-06-18 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-18 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-18 23:59:59' AND [outTime] >= '2011-06-18 00:00:00'),
valDiff13 AS (SELECT datediff(second,CASE WHEN '2011-06-19 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-19 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-19 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-19 23:59:59' END else case WHEN '2011-06-19 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-19 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-19 23:59:59' AND [outTime] >= '2011-06-19 00:00:00'),
valDiff14 AS (SELECT datediff(second,CASE WHEN '2011-06-20 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-20 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-20 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-20 23:59:59' END else case WHEN '2011-06-20 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-20 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-20 23:59:59' AND [outTime] >= '2011-06-20 00:00:00'),
valDiff15 AS (SELECT datediff(second,CASE WHEN '2011-06-21 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-21 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-21 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-21 23:59:59' END else case WHEN '2011-06-21 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-21 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-21 23:59:59' AND [outTime] >= '2011-06-21 00:00:00'),
valDiff16 AS (SELECT datediff(second,CASE WHEN '2011-06-22 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-22 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-22 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-22 23:59:59' END else case WHEN '2011-06-22 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-22 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-22 23:59:59' AND [outTime] >= '2011-06-22 00:00:00'),
valDiff17 AS (SELECT datediff(second,CASE WHEN '2011-06-23 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-23 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-23 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-23 23:59:59' END else case WHEN '2011-06-23 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-23 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-23 23:59:59' AND [outTime] >= '2011-06-23 00:00:00'),
valDiff18 AS (SELECT datediff(second,CASE WHEN '2011-06-24 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-24 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-24 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-24 23:59:59' END else case WHEN '2011-06-24 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-24 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-24 23:59:59' AND [outTime] >= '2011-06-24 00:00:00'),
valDiff19 AS (SELECT datediff(second,CASE WHEN '2011-06-25 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-25 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-25 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-25 23:59:59' END else case WHEN '2011-06-25 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-25 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-25 23:59:59' AND [outTime] >= '2011-06-25 00:00:00'),
valDiff20 AS (SELECT datediff(second,CASE WHEN '2011-06-26 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-26 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-26 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-26 23:59:59' END else case WHEN '2011-06-26 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-26 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-26 23:59:59' AND [outTime] >= '2011-06-26 00:00:00'),
valDiff21 AS (SELECT datediff(second,CASE WHEN '2011-06-27 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-27 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-27 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-27 23:59:59' END else case WHEN '2011-06-27 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-27 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-27 23:59:59' AND [outTime] >= '2011-06-27 00:00:00'),
valDiff22 AS (SELECT datediff(second,CASE WHEN '2011-06-28 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-28 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-28 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-28 23:59:59' END else case WHEN '2011-06-28 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-28 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-28 23:59:59' AND [outTime] >= '2011-06-28 00:00:00'),
valDiff23 AS (SELECT datediff(second,CASE WHEN '2011-06-29 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-29 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-29 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-29 23:59:59' END else case WHEN '2011-06-29 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-29 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-29 23:59:59' AND [outTime] >= '2011-06-29 00:00:00'),
valDiff24 AS (SELECT datediff(second,CASE WHEN '2011-06-30 00:00:00' < [inTime] THEN [inTime] ELSE '2011-06-30 00:00:00' END, CASE WHEN isdate([outTime]) = 1 THEN CASE WHEN '2011-06-30 23:59:59' > [outTime] THEN [outTime] ELSE '2011-06-30 23:59:59' END else case WHEN '2011-06-30 23:59:59' > [inTime] + 604800 THEN [inTime] + 604800 ELSE '2011-06-30 23:59:59' END END) AS v1 FROM [dbo].[Info] WHERE [cName] LIKE 'T%' AND [b] <> 0 AND CONVERT(INT, [evt]) & 7 = 4 AND isdate([inTime]) = 1 AND [inTime] <= '2011-06-30 23:59:59' AND [outTime] >= '2011-06-30 00:00:00')
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff0
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff1
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff2
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff3
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff4
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff5
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff6
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff7
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff8
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff9
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff10
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff11
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff12
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff13
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff14
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff15
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff16
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff17
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff18
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff19
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff20
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff21
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff22
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff23
UNION ALL
SELECT SUM(CASE WHEN v1 < 604800 THEN v1 ELSE 604800 END) FROM valDiff24
如何优化这样的东西？
答案 0 :(得分：2)
首先，我会尝试通过创建一个Calendar表来缩短它。这也可以部分改善绩效......
WITH
Calendar AS
(
SELECT 0 AS [id], CAST('2011 Jun 06' AS DATETIME) AS [DateStart], CAST('2011 Jun 06' AS DATETIME) + 1 AS [DateEnd]
UNION ALL
SELECT id + 1, [DateStart] + 1, [DateStart] + 2 FROM Calendar WHERE id < 24
)
,
FilteredData AS
(
SELECT
COALESCE(Info.[inTime], CAST('2011 Jun 06')) AS [inTime],
COALESCE(Info.[outTime], Info.[inTime] + 7) AS [outTime]
FROM
[dbo].[Info]
WHERE
Info.[cName] LIKE 'T%'
AND Info.[b] <> 0
AND CONVERT(INT, Info.[evt]) & 7 = 4
AND (Info.[outTime] IS NULL OR Info.[outTime] >= CAST('2011 Jun 06' AS DATETIME)
AND (Info.[inTime] IS NULL OR Info.[inTime] < CAST('2011 Jun 06' AS DATETIME) + 25)
)
,
CleanedData AS
(
SELECT
[Calendar].id,
CASE
WHEN Calendar.[DateStart] < Info.[inTime] THEN Info.[inTime]
ELSE Calendar.[DateStart]
END AS [inTime],
CASE
WHEN Calendar.[DateEnd] > Info.[outTime] THEN Info.[outTime]
ELSE Calendar.[DateEnd]
END AS [outTime]
FROM
[Calendar]
INNER JOIN
[FilteredData] AS [Info]
ON Info.[inTime] < Calendar.[DateEnd]
AND Info.[outTime] >= Calendar.[DateStart]
)
SELECT
[id],
SUM(DATEDIFF(SECOND, [InTime], [OutTime])) AS duration
FROM
[CleanedData]
GROUP BY
[id]
-- Note: The CleanedData step causes the InTime and OutTime to be no more than a day appart.
-- This means that there is no need to check the DATEDIFF is less than 1 week long.
在优化方面，您在桌面上有哪些索引？他们当然可以帮助......
WHERE
Info.[cName] LIKE 'T%'
AND Info.[b] <> 0
最后，索引无法帮助CONVERT(INT, Info.[evt]) & 7 = 4。您是否能够将计算字段添加到表中，您可以将其编入索引？或者将单个字段更改为多个字段;不同模式/状态的一组标志？ （或者制作一个这个信息的派生表？）或者对这个字段建立索引对你没有多大影响？
你有逻辑说“如果outTime为NULL，则使用inTime加1周”。如果inTime和OutTime都为NULL，你想做什么？
根据您感兴趣的日期，还有一个关于过滤数据的优化问题。如果某个事件任何持续时间，您必须检查两者 in和out次，会影响您使用索引的能力。但是，如果您知道某个事件的最大长度，则可以执行以下操作...
WHERE
Info.inTime > (myEarliestDate) - (myLongestDuration)
AND Info.inTime < (myLatestDate)
AND Into.OutTime > (myEarliestDate)
给你的是>和<包围你的inTime字段，明确地将所有内容限制在非常特定的数据范围内。因此，我将其添加到名为FilteredData的WHERE子句的末尾。 （假设任何事件都不会超过7天。）
AND (Info.[inTime] IS NULL OR Info.[inTime] >= CAST('2011 Jun 06' AS DATETIME) - 7)