通过pdo使用表变量执行存储过程

I have a stored procedure with two seperate select statements. The results are saved in a table variable. In the end of the SP the table variable is outputted.

So, if I execute the SP on the server itself (via MS SQL Server Management Studio) the reslut is like expected. But when I try to call the SP in PHP it doesn't work anymore.

Here is my PHP code:

$querySelectRemindersToBeExecuted = $this->dbConnectionWAM->prepare("{call spGetRemindersToBeExecuted}");

if($querySelectRemindersToBeExecuted->execute(array()))
{                
    var_dump($querySelectRemindersToBeExecuted->fetch()); // returns false
    while($row = $querySelectRemindersToBeExecuted->fetch())
    {
        echo "fetching";
    }
    var_dump($querySelectRemindersToBeExecuted->errorInfo()); // returns error message below
}
else
     var_dump($querySelectRemindersToBeExecuted->errorInfo()); // no error

Error message from the second var_dump:

array (size=3)
  0 => string 'IMSSP' (length=5)
  1 => int -15
  2 => string 'The active result for the query contains no fields.' (length=51)

Thank you very much for your help!