The PDO extension is required for this adapter but the extension is not loaded

Question

I am getting the following exception when i try to use the fetchall method of the Zend_Db_Table_Abstract class...

An error occurred4545
EXCEPTION_OTHER
Exception information:
Message: The PDO extension is required for this adapter but the extension is not loaded 

Stack trace:
#0 D:\www\TestProject\library\Zend\Db\Adapter\Pdo\Mysql.php(96): Zend_Db_Adapter_Pdo_Abstract->_connect()
#1 D:\www\TestProject\library\Zend\Db\Adapter\Abstract.php(448): Zend_Db_Adapter_Pdo_Mysql->_connect()
#2 D:\www\TestProject\library\Zend\Db\Adapter\Pdo\Abstract.php(238): Zend_Db_Adapter_Abstract->query('DESCRIBE `album...', Array)
#3 D:\www\TestProject\library\Zend\Db\Adapter\Pdo\Mysql.php(156): Zend_Db_Adapter_Pdo_Abstract->query('DESCRIBE `album...')
#4 D:\www\TestProject\library\Zend\Db\Table\Abstract.php(823): Zend_Db_Adapter_Pdo_Mysql->describeTable('albums', NULL)
#5 D:\www\TestProject\library\Zend\Db\Table\Abstract.php(862): Zend_Db_Table_Abstract->_setupMetadata()
#6 D:\www\TestProject\library\Zend\Db\Table\Abstract.php(969): Zend_Db_Table_Abstract->_setupPrimaryKey()
#7 D:\www\TestProject\library\Zend\Db\Table\Select.php(100): Zend_Db_Table_Abstract->info()
#8 D:\www\TestProject\library\Zend\Db\Table\Select.php(78): Zend_Db_Table_Select->setTable(Object(Application_Model_Albums))
#9 D:\www\TestProject\library\Zend\Db\Table\Abstract.php(1005): Zend_Db_Table_Select->__construct(Object(Application_Model_Albums))
#10 D:\www\TestProject\library\Zend\Db\Table\Abstract.php(1303): Zend_Db_Table_Abstract->select()
#11 D:\www\TestProject\application\controllers\IndexController.php(17): Zend_Db_Table_Abstract->fetchAll()
#12 D:\www\TestProject\library\Zend\Controller\Action.php(513): IndexController->indexAction()
#13 D:\www\TestProject\library\Zend\Controller\Dispatcher\Standard.php(289): Zend_Controller_Action->dispatch('indexAction')
#14 D:\www\TestProject\library\Zend\Controller\Front.php(954): Zend_Controller_Dispatcher_Standard->dispatch(Object(Zend_Controller_Request_Http), Object(Zend_Controller_Response_Http))
#15 D:\www\TestProject\library\Zend\Application\Bootstrap\Bootstrap.php(97): Zend_Controller_Front->dispatch()
#16 D:\www\TestProject\library\Zend\Application.php(366): Zend_Application_Bootstrap_Bootstrap->run()
#17 D:\www\TestProject\public\index.php(26): Zend_Application->run()
#18 {main}  
Request Parameters:
array (
  'controller' => 'index',
  'action' => 'index',
  'module' => 'default',
)  

I have added the following lines in the php.ini file

extension=pdo.so
extension=pdo_mysql.so

extension=php_pdo.dll 
extension=php_pdo_mssql.dll 

Also i have The PDO MySQL package installed in my system. But still I am getting the above exception.... (Also restarted the Apache server)

Answer 1

First of all, you cannot have both :

extension=pdo.so
extension=pdo_mysql.so

Which are for Linux, and :

extension=php_pdo.dll 
extension=php_pdo_mssql.dll 

Which are for windows : you've got to choose, depending on the system you are using.

As you are on windows, you should use the .dll version.

But note that you used :

extension=php_pdo_mssql.dll 

i.e. you loaded the pdo_mssql extension -- which is for Microsoft SQL Server, and not MySQL.

Instead, you should load the extension for MySQL :

extension=php_pdo_mysql.dll 

After correcting that, restart Apache ; and things should get better.

If things don't get better, you should check the output of phpinfo() :

• At the beginning of phpinfo()'s output, it indicates which php.ini file is loaded ; make sure you modified the right one.
• Check, lower in the file, if there is a section about pdo_mysql
  • If not, check Apache's error_log, just in case ;-)