sql sever 时间差 小时
DATEDIFF(类型,开始时间,结束时间)
DATEADD(类型,时间间隔,时间)
CAST(数据 as 转换类型)
DATEDIFF(HOUR,DATEADD( HOUR,sf.kaiShiShiJian_hour , CAST( sf.kaiShiShiJian_date AS DATETIME) ), DATEADD( HOUR,sf.jieShuShiJian_hour , CAST(sf.jieShuShiJian_date AS DATETIME) )) chiXvShiJian,