title: display constraints of Certain table in Postgresql
body: <p>I want to know how to display all constraints of a certain table(all columns) by the SELECT statement in PostgreSQL. I tried this code:</p>
  
  <pre><code>SELECT * FROM information_schema.table_constraints;
  SELECT * FROM information_schema.referential_constraints;
  </code></pre>
  
  <p>Actually, I want the primary keys and foreign keys of the tables</p>