Logic for self-calling button

I am a beginner and I am sorry in advance if I fail to make sense with my question.

I have a PLC that sends a signal that is then translated and stored in a database. The table stores the following: - InvokeID (auto increment/unique) - Date (yyyy.MM.dd hh:mm:ss) - Maintenance boolean - Logistics boolean

Using the above information I need to come up an if statement that would allow me to call the maintenance/logistics button each time a new signal is sent in (record is added to the data table), but it should only do so once for each signal/record in the table.

The buttons are on a web-page that refreshes every few seconds, so I must ensure that the if statement is called once only for each record/signal.