title: Add a Foreign Key in PgAdmin
body: <p>I have <code>studidtemplates</code> table below:</p>
  
  <p><a href="https://i.stack.imgur.com/fSHCa.png" rel="noreferrer"><img src="https://i.stack.imgur.com/fSHCa.png" alt="enter image description here"></a></p>
  
  <p><code>template_id</code> is the primary_key</p>
  
  <p><a href="https://i.stack.imgur.com/JQ9vn.png" rel="noreferrer"><img src="https://i.stack.imgur.com/JQ9vn.png" alt="enter image description here"></a></p>
  
  <p>I want to create a new table referencing <code>template_id</code> as a <code>foreign key</code>. It is named <code>studidtemplatetextelements</code>. See image below:</p>
  
  <p><a href="https://i.stack.imgur.com/WNCk0.png" rel="noreferrer"><img src="https://i.stack.imgur.com/WNCk0.png" alt="enter image description here"></a></p>
  
  <p>I created a column <code>template_id</code> in the second table and want to make it a foreign key referencing <code>template_id</code> in <code>studidtemplates</code> table. I did it by clicking the button in the <code>Constraints</code> tab,pointed by an arrow in the image below.</p>
  
  <p><a href="https://i.stack.imgur.com/S2Gsh.png" rel="noreferrer"><img src="https://i.stack.imgur.com/S2Gsh.png" alt="enter image description here"></a></p>
  
  <p>I notice something different. In 'Referencing' option there's no <code>template_id</code> option available. See image below:</p>
  
  <p><a href="https://i.stack.imgur.com/gCkBf.png" rel="noreferrer"><img src="https://i.stack.imgur.com/gCkBf.png" alt="enter image description here"></a></p>
  
  <p>Where am I missing?</p>