How can I restrict number of entries?

[djl0525]

I have two tables, Employees and Parking. Each employee can have up to 3 hangtags issued by the parking department so my tables have a 1:M relationship.

My question is, what is the best way to restrict the number of hangtags to 3? In other words, how do I make sure that an employee is not entered into the Parking table more than three times?

I hope I have provided enough information. Any guidance will be greatly appreciated.

DJ

 

[Joe4]

How is the data entered into the Parking table?
Is someone manually entering it via a Form, or is data being imported?

 

[djl0525]

Manually via form.

 

[Joe4]

I would then recommend running a "BeforeUpdate" script that checks for the number of records for that person before adding the new one.
See here for "BeforeUpdate" events: https://docs.microsoft.com/en-us/office/vba/api/access.form.beforeupdate(even)

You should be able to use the DCOUNT function to count the number of existing records for the user being entered to check if it is less than 3.
See: https://www.techonthenet.com/access/functions/domain/dcount.php

 

[djl0525]

Cool! I’ll give it a try. Thank you very much!

DJ