title: Merging different user master tables in to one user master
body: <p>I have tree projects running in production with three different <code>Postgres</code> databases which manage their users individually and the tables are given below.</p>
  
  <hr>
  
  <p><strong>Sales Panel</strong> --> Database: salesDB, Table: user_master (id, name), other_table1,...</p>
  
  <p><strong>Talent Panel</strong> --> Database: talentDB, Table: employee_master (id, name), other_table2, ...</p>
  
  <p><strong>Buyer Panel</strong> --> Database: buyerDB, Table: buyer_master (id, name), other_table3, ...</p>
  
  <hr>
  
  <blockquote>
    <p>Now I want to manage all users in one new table by creating a new database for Admin Panel.</p>
  </blockquote>
  
  <p>Example:
  <strong>Admin Panel</strong> --> Database: adminDB, Tables   : user_master (id, name)</p>
  
  <hr>
  
  <p>Question is,</p>
  
  <blockquote>
    <p>1) If I create new user_master table then how to manage existing user's primary id which is in use?</p>
  </blockquote>
  
  <p>If there is another way then please suggest me.</p>