title: How to create unique constraints in laravel 5.2?
body: <p>How do I create unique constraints using laravel 5.2 Schema Builder?</p>
  
  <pre><code>Schema::create('my_pivot', function(Blueprint $table){
  
      $table-&gt;increments('id');
      $table-&gt;integer('table1_id')-&gt;unsigned();
      $table-&gt;integer('table2_id')-&gt;unsigned();
  
      $table-&gt;foreign('table1_id')-&gt;references('id')-&gt;on('table1');
      $table-&gt;foreign('table2_id')-&gt;references('id')-&gt;on('table2');
  
      //Here i need to add an unique constraint to 'key1' + 'key2'
  
  });
  </code></pre>