The datediff curdate valid_upto will return a negative value until the valid_upto date comes;when the difference is greater than 0 that means your subscription has expired

Datediff becomes more difficult to use as you have more dateparts in your difference in your case looks like minutes and seconds

I want to find the difference between two dates which should be exact in months like if the date difference is greater than 182 days them on 183rd day it should show as 7 months.i tried below one select round cast datediff dd 2018-01-01 18 45 30.203 getdate as float 30 0 but it has 15 days difference

You ll need lag and datediff to get the number of minutes between tran_date and the previous row;then basically a running total on the evaluation of whether or not the time difference is greater than 30

Note that diffseconds can cause an overflow when the difference becomes larger than int32.maxvalue error the datediff function resulted in an overflow

You can use datediff instead in this case but it s worth being aware that datediff doesn t always do exactly what you might expect it to as it s about boundary crossings;not much of an issue here but it means that the difference between say september 1st and august 31st is 1 month as is the difference between september 30th and august 1st