title: Connecting one foreign key to multiple tables (primary keys)
body: <p>I am developing an application for making quotations. First you make cost break down (or calculation) and upon that result you add item to quotation. The problem is that i have many product, so each category of a product will have its own cost break down form with different parameters to be filled in. If I will have only one table for cost breakdown, then it will be huge (a lot of fields in table). I have a feeling that this is not the right approach. So I came up with diagram below:</p>
  
  <p><img src="https://i.stack.imgur.com/N6uF9.jpg" alt="My diagram"></p>
  
  <p>Is this solution even possible, or I must have "N" (if I have N-tables) different FK for each cost break down table? Do you have any better solutions?</p>
  
  <p>I have another question if my linking table "Quotation_QtnDetail" is necessary?</p>