用 SQL 计算时间差值

 ;WITH res1 AS
 (
 SELECT * FROM
 (
 SELECT ROW_NUMBER() OVER (PARTITION BY F2 ORDER BY F1) AS rn,F1,F2 FROM dbo.test
 ) a WHERE a.rn=1
 ),
 res2 AS
 (
 SELECT * FROM (
 SELECT ROW_NUMBER() OVER (PARTITION BY F2 ORDER BY F1) AS rn,F1,F2 FROM dbo.test
 ) b WHERE b.rn=2
 )
 SELECT res1.F2,CONVERT(VARCHAR(50),DATEDIFF(ms,res1.F1,res2.F1)) FROM res1
 INNER JOIN res2
 on res1.F2=res2.F2