title: mysql copy from one table column to another empty table with intergrity contraints
body: <p>I have a table called </p>
  
  <pre><code>     Seats
  ID   Number  Region_ID  Venue_ID
  
  
       seatreservation
  ID   Flag   seat_ID    reservation_ID
  </code></pre>
  
  <p>Now the seatreservation table is empty but has reservation_ID as a foreign key to another table. So i am trying to copy the contents from Seats.ID and put it in seatreservation.seat_ID  where for example Region_ID is =2. If i use an insert statement 
  like  :  </p>
  
  <p><code>INSERT INTO seatreservation (seat_ID) SELECT ID FROM seat WHERE venue_ID = 2;</code></p>
  
  <p>It wont work because reservation_ID on seatreservation cannot be null(referential integrity). Is there a way to fill the seat_ID column from Seats.ID while also inserting for example "1" for all reservation_IDs in the loop to avoid null ? I need help in extending the sql statement or another approach please.</p>