Zend | Db \\ Sql | Expression在Zend SL语句中不起作用

Question

I cannot get valid data from the Zend Framework sql statements shown below which I use in php and is called from an angularjs script:

    $where = new Where ();   
    $where->greaterThanOrEqualTo('user_id', '963');  
    $resultSet = $this->tableGateway->select(function(Select $select) use
    ($where){
    $select->where($where);  
      $select->columns(array('date_added','datemonth' => new \Zend\Db\Sql\Expression("MONTH('date_added')"), 'count' => new \Zend\Db\Sql\Expression("COUNT(*)")));
    $select->group('datemonth');
    return $resultSet;

My angular js script dumps the data as shown below:

    success(function(response) {

            for(var i in response.response) {
                var tc = response.response[i];
                alert("userdata date_added=" + tc['date_added'] + " datemonth=" + tc['datemonth'] + " count=" + tc["count"]);
         }

And the results are as shown:

userdata date_added=2014-05-22 20:00:27 datemonth=undefined count=undefined

Can anyone tell me if I am using the Zend\\Db\\Sql\\Expression incorrectly or why isn't the datemonth and count not coming back correctly? I want to be able to get the number of records by month.

Update: I was able to dump the putput from the server and it shows all the fields on the database record but none for the fields created in the Zend Expression functions for datemonth and count. Below is the dump. Anyone know why the Expression fields aren't in the dump?

Php Code:

       echo "Resultset = " . $resultSet->date_added;

Dump of above code:

       Resultset = {"success":true,"response":[{"inputFilter":null,"user_id":0,"instagram_user_id":"","fbid":"","instagram_username":null, "full_name":"","profile_image":"","bio":"","website":"","media_count":0,"following_count":0,"followed_by_count":0,"like_count":0,"recommend_count":0,"date_added":"2014-05-22 20:00:27","flag_count":0,"date_updated":"","email":"","password":"","access_token":"","premium":0,"login_attempts":0,"status":0,"request_count":0,"request_date":""}]}

Answer 1

You may try this to preview your SQL query:

$sql = new \Zend\Db\Sql\Sql($this->tableGateway->adapter);
echo $sql->getSqlStringForSqlObject($select);