When we are doing an insert of huge no.of rows into an SQL table ,Normally we will try to write separate insert quries this may lead us to a long duration of execution time and we can increase the speed of executing SQL quries by adding all the rows into a single insert query.
If you are testing your app and use urlManager in your config, sometimes you will find a problem: you want to test your site independing from urlManager settings. in that way you need to extend your WebTestCase class by this method:
Some PHP installations may use a different php.ini file for CLI PHP (command line PHP parser). As a result, when running the model or crud command in yiic shell, you may encounter errors like "YiiBase::include(PDO.php): failed to open stream..." or "...could not find driver", even though the requirement checker confirms you have PDO and the corresponding database driver.