title: concat in php codeigniter
body: <p>Please help me to understand proper join syntax.</p>
  
  <p>I have table named <em>inventory</em> which has: </p>
  
  <pre><code>trans_id    
  trans_items items -&gt; item_id         
  trans_user  employees -&gt; person_id           
  trans_date                   
  trans_comment                
  trans_inventory     
  </code></pre>
  
  <p>As you can see above, trans_items is a foreign key in items table, and trans_user is a foreign key in employees table and employee id is foreign key to people table.</p>
  
  <p>Now what I want to do is to display in HTML the inventory table, but instead of displaying the employee id, I want the employee NAME to be displayed.</p>
  
  <hr>
  
  <p>EDIT................................................
  so i was enable to display only the last name of the employee with this code:</p>
  
  <pre><code>$this-&gt;db-&gt;select('inventory.*, items.name ,people.last_name');
  $this-&gt;db-&gt;from('inventory');
  $this-&gt;db-&gt;join('items', 'inventory.trans_items = items.item_id' , 'left');
  $this-&gt;db-&gt;join('people', 'inventory.trans_user = people.person_id' , 'left');
  $this-&gt;db-&gt;where('deleted', 0);
  $this-&gt;db-&gt;order_by('trans_date desc');
  </code></pre>
  
  <p>with the model code:</p>
  
  <pre><code>foreach($report_data as $row)
          {
              $tabular_data[] = array($row['name'], $row['last_name'],$row['trans_date'], $row['trans_inventory'], $row['trans_comment']);
          }
  </code></pre>
  
  <p>but i need it to be first name and last name so i did these:</p>
  
  <pre><code>$this-&gt;db-&gt;select('inventory.*, items.name ,CONCAT(people.first_name, " ",people.last_name) as employee');
  $this-&gt;db-&gt;from('inventory');
  $this-&gt;db-&gt;join('items', 'inventory.trans_items = items.item_id' , 'left');
  $this-&gt;db-&gt;join('people', 'inventory.trans_user = people.person_id' , 'left');
  $this-&gt;db-&gt;where('deleted', 0);
  $this-&gt;db-&gt;order_by('trans_date desc');
  </code></pre>
  
  <p>with the model code:</p>
  
  <pre><code>foreach($report_data as $row)
          {
              $tabular_data[] = array($row['name'], $row['employee'],$row['trans_date'], $row['trans_inventory'], $row['trans_comment']);
          }
  </code></pre>
  
  <p>it would error if i would use concat function. please help.</p>