subtracting dates

Summary

OTBI subtracting dates

Content

I require a column that returns the difference between the current date/time and a column in OTBI, the results must be measured in hours.

I have tried this formula:

timestampdiff (SQL_TSI_hour,"Job Application - Job Application Dates"."Job Application Last Update Date",cast(current_date as timestamp)) 

It gives results in hours but the values are not correct. I think the "current_date" is always calculating as 12:00AM and not the current time. Is there a formula that could give an accurate difference in hours?