title: Update SQL database to Wordpress date format
body: <p>I have a custom SQL database (<code>database</code>) and table (<code>portfolio</code>) with columns arranged as follows:</p>
  
  <p>Col 1:<code>id</code></p>
  
  <p>Col 2:<code>year</code></p>
  
  <p>Col 3: <code>month</code></p>
  
  <p>Col 4: <code>day</code></p>
  
  <p>Col 5: <code>title</code></p>
  
  <p>etc.</p>
  
  <p>I want to concatenate columns 2 to 4 in one single column (<code>date</code>) using Wordpress posts date format (ie. <code>YYYY-MM-DD 00:00:00</code>). All times can have <code>00:00:00</code> value.</p>
  
  <p>This is my query:</p>
  
  <pre><code>SELECT id, CONCAT(`year`,"-", `month`,"-",`day`," 00:00:00") FROM `portfolio`
  </code></pre>
  
  <p>How can I insert result into a new column named <code>date</code>?</p>