一種方式做到這一點,如果tagID
值已知前期是使用條件聚集
SELECT TimeSeconds,
COALESCE(MAX(CASE WHEN TagID = 'A1' THEN Value END), 'n/a') A1,
COALESCE(MAX(CASE WHEN TagID = 'A2' THEN Value END), 'n/a') A2,
COALESCE(MAX(CASE WHEN TagID = 'A3' THEN Value END), 'n/a') A3,
COALESCE(MAX(CASE WHEN TagID = 'A4' THEN Value END), 'n/a') A4
FROM table1
GROUP BY TimeSeconds
,或者如果你有NULL
值,而不是'n/a'
SELECT TimeSeconds,
MAX(CASE WHEN TagID = 'A1' THEN Value END) A1,
MAX(CASE WHEN TagID = 'A2' THEN Value END) A2,
MAX(CASE WHEN TagID = 'A3' THEN Value END) A3,
MAX(CASE WHEN TagID = 'A4' THEN Value END) A4
FROM table1
GROUP BY TimeSeconds
或PIVOT
OK
SELECT TimeSeconds, A1, A2, A3, A4
FROM
(
SELECT TimeSeconds, TagID, Value
FROM table1
) s
PIVOT
(
MAX(Value) FOR TagID IN (A1, A2, A3, A4)
) p
路輸出(帶有NULL
S):
TimeSeconds A1 A2 A3 A4
----------- ------- ------ ----- -----
1378700244 3.75 NULL NULL NULL
1378700245 30.00 NULL NULL NULL
1378700304 1.20 NULL NULL NULL
1378700305 NULL 56.00 NULL NULL
1378700344 NULL 11.00 NULL NULL
1378700345 NULL NULL 0.53 NULL
1378700364 4.00 NULL NULL NULL
1378700365 14.50 NULL NULL NULL
1378700384 144.00 NULL NULL 10.00
如果你要搞清楚TagID
值進行動態再使用動態SQL
DECLARE @cols NVARCHAR(MAX), @sql NVARCHAR(MAX)
SET @cols = STUFF((SELECT DISTINCT ',' + QUOTENAME(TagID)
FROM Table1
ORDER BY 1
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)'),1,1,'')
SET @sql = 'SELECT TimeSeconds, ' + @cols + '
FROM
(
SELECT TimeSeconds, TagID, Value
FROM table1
) s
PIVOT
(
MAX(Value) FOR TagID IN (' + @cols + ')
) p'
EXECUTE(@sql)
Thansk爲你的想法。我認爲我的知識仍然停留在SQL Server 2000時代。必須開始學習如何使用數據透視表。 – user3015739