title: How to assign primary key values into foreign keys?
body: <p>I don't think that I could be specific in the title about my problem. Let me put it this way, getting away from talking about the project's content.</p>
  
  <p>I have many of tables in my database, two of which are <code>Persons</code> and <code>Address</code>. In need of normalisation and setting many-to-many relations between these two entities, I don't keep any foreign keys in these tables referencing each other. For example, I don't store a foreign key to Address table, in Person table</p>
  
  <p>Instead, my foreign keys are in a third table named <code>PersonAddress</code>. This table includes nothing but only two foreign keys referencing primary keys in their own tables (<code>Person</code>,<code>Address</code>)</p>
  
  <p>In Microsoft SQL Server, we linked the table in question into the other two, making the attributes (<code>PersonId, AddressId</code>) of the table named <code>PersonAddress</code> <strong>foreign keys</strong> to the other two tables,  allowing delete and update cascading operation. (anyway) </p>
  
  <p>At the first time, it seemed that it would work very well. However, once we kept inputting data into the database, it occurred that foreign key values remained unchanged in the third table, where we could see each primary key value in both tables Person and Address</p>
  
  <p>Any help would be appreciated and thank you in advance for your prospective attempts, guys.</p>