Discussions

The field "Agency Name" in "Table A" is currently a unique field so you cannot input an agency in twice. 

Can this field also check for duplicates in a different table? So it is a unique field that will look for duplicates in "Table B" and bounce back an error message or something if the 'Agency Name: already exists in "Table B"? Thanks guys

This would not be a native capability. You could do it with a script after the record is saved, and it could check a box to alert you that it exists on a different table. 

If the Agency name in Table B was able to be set up as the Key field on Table B, then upon saving a record in Table A, there  can be a message saying that the Agency name already exists.  If the Agency name cannot be the Key field - say that it is in fact the Customer Name and you are logging leads in Table A and don't want to duplicate exsting customers as leads, then you can do a Sync table of the customers and make the Key field in the Sync table be the key field.

That can be done natively with no script.

I think Mark and I interpreted the question 2 different ways. My interpretation was that when adding a new record on table A and entering a unique value into a field on table A, can that action also check EXISTING records in other tables to determine if that value already existed.

This is the question I intended yes. I was hoping a script page wouldn't be the way to go, but I think you are right. Thanks to the both of you guys! Always helping out

I think that Mathew is saying that a script could prevent the save and I'm saying that natively I cannot prevent the save but I can flag the record.  I don't know your  business process, but sometimes a solution is that the user first  enters the customer and saves.  Then the edit the record and the rest of the data entry fields appear along with the warning message, if any.  If the warning message appears, then the user will know and also a form rule could hide the rest of the data entry sections.  

That way the user will not waste time with a lot of data entry needlessly and can "cut their losses' more quickly.