如何在Joomla 1.5中創建SQL事務？

Question

我已經成功地在Joomla中創建了一個用戶可以更新數據庫內容的組件。問題是我有兩個查詢要執行，如果第二個查詢失敗，第一個查詢完成的更改應該被丟棄。我試過這些代碼，它不給我回滾：

$db = JFactory::getDBO(); 

    $db->setQuery("BEGIN"); 
    $db->query(); 
    $db->setQuery($delete_script); 
    $db->query(); 
    $db->setQuery($update_script); 
    $db->query(); 

    if($db->getErrorMsg()) 
    { 
     $db->setQuery("ROLLBACK"); 
     $db->query(); 
     JFactory::getApplication()->enqueueMessage(JText::_($sql_script . 'An error occurred while saving loan types. Please check formatting and try again.'), 'error'); 
    } 
    else 
    { 
     $db->setQuery("COMMIT"); 
     $db->query(); 
     JFactory::getApplication()->enqueueMessage(JText::_('Loan types have been saved successfully!'), 'message'); 

    } 

    JRequest::setVar('view', 'loantypes'); 
    parent::display(); 

那麼你如何在Joomla 1.5中創建一個事務？

Answer 1

你應該執行這樣的：

$db = JFactory::getDBO(); 

$db->setQuery("BEGIN"); 
$db->query(); 

$db->setQuery($delete_script); 
$db->query(); 
if($db->getErrorMsg()) { 
    $db->setQuery("ROLLBACK"); 
    $db->query(); 
    JFactory::getApplication()->enqueueMessage(JText::_($sql_script . 'An error occurred while saving loan types. Please check formatting and try again.'), 'error'); 
} 
$db->setQuery($update_script); 
$db->query(); 

if(!$db->getErrorMsg()) { 
    $db->setQuery("COMMIT"); 
    $db->query(); 
    JFactory::getApplication()->enqueueMessage(JText::_('Loan types have been saved successfully!'), 'message'); 

} 

JRequest::setVar('view', 'loantypes'); 
parent::display(); 

回滾必須在近期執行的查詢被執行。