# 3016 Trying to Alter an Existing Table and Add a Foreign Key that References the Same Table Causes AV

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I have a table that contains contacts, which can be either a person or a company. If its a person, then that person can link to a company record, which is also in the same table. I want to set up a foreign key constraint to make sure that the link is not accidentally compromised. I tried to do this in the EDBManager but got an Access violation.