Encapsulates interface to the actual database.
The DataProviderBase class is located in the file /libraries/pj/DataProvider.php. It implements several concepts:
- It is the interface between Joomla! CMS and the actual DataProvider (MySqlDataProvider only implemented yet). It reads connection settings from JFactory::getConfig(), instantiates the DataProvider, opens database connection and registers several basic Joomla! and PJ classes1;
- intermediates general DataProvider functions like retrieving tables and fields information and executing queries;
- implements basic handling functions for counting, retrieving, listing, updating and deleting of InfoBase objects;
- implements recursive transaction mechanism;
- implements the concept of PJVisitorInfo;
- provides base for development of extension and module specific Joomla! DataProvider classes.
The DataProviderBase class isn't intended for instantiating itself. Instead, the extending class should declare a static instance() function creating a singleton instance. See DataProviderBase API and DataProviderBase Example for further details.
1 The basic registered Joomla! classes are UserInfo, UserProfileInfo, MenuInfo, ModuleInfo, ModuleMenuInfo and ExtensionInfo. Other defined, yet not registered Joomla! classes are CategoryInfo, ContentInfo and LanguageInfo. All predefined Joomla! classes are located in the file /libraries/pj/JoomlaInfo.php. Registered PJ classes are PJVisitorInfo and PJVisitorTcpipInfo, both located in the file /libraries/pj/VisitorInfo.php.