Does anyone use a SQL to check for ‘last update Date’ in a database?

wwise

Does anyone use a SQL to check for ‘last update Date’ in a database?

We want to look at ’last update Date’  in a datafile and if less than 30min we want to receive an Alert.

I have the SQL code but where I am struggling is how to set it up?  I know we can put the code in a Template but what is the Trigger to get it to continue to check and when longer than 30min to get the Alert? Any help will be appreciated.