title: Foreign Key referring one field of two tables in oracle
body: <p>I am trying to set a Foreign Key by refering to different tables.</p>
  
  <p>Imagine the tables: </p>
  
  <p>Active_Card((primary key)Num_id number, num_card number,is_active varchar2); </p>
  
  <p>TMP_CARD((PK)num_card number, reg_date date);</p>
  
  <p>DEFINITIVE_CARD((PK num_card number, name varchar, create_date date)</p>
  
  <p>So num_card is foreign key of Active_Card. My problem is how to refer both tables (TMP_CARD and DEFINITIVE_CARD) in Active_card.</p>
  
  <p>best regards, </p>