Hi. I want to apply a unary relationship to my database. I tried a lot, searched a lot, but couldn't find an answer. To make it quick and easy, here's my problem: iam making a contacts database in MS Access. The contacts table contain first, middle, and last names for each person, and other attributes that doesn't relate to my problem. I want to create a unary relationship (parent-child), where each person have an attribute, that is a foreign key for his or her father or mother's primary key. What i thought of is to make a supertype/subtype relationship, where each person can be a parent, child, or both. So the final question would be: Is there a way to apply unary relationships in MS Access? If yes, how? If no, is it done by using supertype/subtype relationship? If yes, thank you. If no, what should i do? Thanks for any help.
Let the table have a simplified structure like mentioned: contactid: ID of the contact being saved name: Name of the contact parentid: His/her parent's ID The SQL statement will return all contacts and corresponding parent id: SELECT a.contactid, a.name, b.parentid, b.name FROM table1 AS a, table1 AS b WHERE a.parentid=b.contactid; Hope this helps...