PHP Yii Complex SQL

Yii allows developers to construct SQL statement.
This will help advanced developer to tune his/her SQL query (by using appropriate indexes).


Example:
$connection=Yii::app()->db;

$sql = "SELECT t1.colA, t2.colB, t3.colC, t3.colD 
           FROM tableA t1 
           LEFT JOIN tableB t2 ON t1.id=t2.id 
           LEFT JOIN tableC t3 ON t2.pid=t3.pid
           WHERE t1.id BETWEEN 10 AND 100 
           ORDER BY t1.modifyDate DESC";
$command = $connection->createCommand($sql);
$dataReader = $command->query();
$result = $dataReader->readAll();


Internal:
$command=createCommand($query)
Note: $command is a CDbCommand
|- $dataReader = query()
   Note: $dataReader is a CDbDataReader
   |- CDBDataReader->readAll() returns array()