$queryBuilder = $this->em->createQueryBuilder();
$queryBuilder->select("e, 99 as number");

array(4) {
  [0]=>
     array(2) {
        [0]=> string(30) "Profile_Entity" //notice this is a string but it should be  an object instance
        ["number"]=> string(2) "99"
     }
  ...
...

$queryBuilder = $this->em->createQueryBuilder();
$queryBuilder->select("e");
$queryBuilder->select("99 as number");

array(4) {
  [0]=> object(stdClass)#935 (39) {
    ["__CLASS__"]=> string(30) "Profile_Entity"
    ["id"]=> int(46)
    ["headline"]=> string(7) "asdasd
    ...
  ...
...

$queryBuilder -> select('table.column1 alias1, table.column2 alias2');

$qb -> select('tableAlias1', 'tableAlias2')
$qb -> from('table1','tableAlias1')
$qb -> leftJoin('table2','tableAlias2');

$qb -> select('tableAlias1.column1', 'tableAlias2.column1')
$qb -> from('table1','tableAlias1')
$qb -> leftJoin('table2','tableAlias2');