SQL-Queries-Date

1. Query from yesterday 5:30pm to today 5:30 pm

DECLARE @today DATETIME, @today_at_1715 DATETIME;

select @yesterday = dateadd(day,datediff(day,1,GETDATE()),0)

SELECT @today = DATEADD(DAY, DATEDIFF(DAY, 0, GETDATE()), 0),

@today_at_1715 = DATEADD(MINUTE, 17.25*60, @today);

SELECT  *

FROM files_tb

WHERE Files_moddt > DATEADD(DAY, -1, @today_at_1715)

AND Files_moddt <= @today_at_1715 and Files_appl = 'MyApp' 

ORDER BY Files_moddt;