Grinding out an Access db upgrade to Access web app.
Original PK in desktop db is now no longer the PK in web app., given the up-sizing uses the record ID as the PK. May not have the experience for this upsize, but all seems well after some great advices at: http://www.ascassociates.biz/WebApp12_ConvertTables.aspx
Followed to the letter (especially the last paragraph on referential integrity) and all is well.
Now onward; user on data entry in the app., can create duplicates in the field that was the PK. Minor issue since all still seem related correctly, but will be when running existing reports on desktop. The duplicates will deliver bad results. What is best method to prevent user from creating a new record using an existing records pseudo PK field?
...or better put, ignoring the PK comment: How to prevent user from entering duplicate data in a given field?