Check & Forbid Duplicate Data in A Month

[yus2aces]

I have a census database where I would like to forbid user insert a new census data if the same ProductID already in the database in the same month.

Thanks for your help. :D

[Seth Schrock]

Create a query that has the criteria of the current Month and the ProductID. Then, do a DCount() of that query and test the value to see if it is greater than 0 using an If/Then/Else statement. If the value is greater than 0, then set Cancel = True. This will stop the form from going to the next record and the form from closing and the data from saving. You can also create a message box telling the user what happened and what they need to do.

[yus2aces]

Thank you so much Seth... I will try your solutions. :D