* @copyright 2001-2007 VIKO team and contributors * @license http://www.gnu.org/licenses/gpl.html GPL 2.0 */ /** * Database Abstraction Layer: {@link http://pear.php.net/package/DB PEAR DB} */ require_once 'DB.php'; require_once 'Configuration.php'; /** * Provides simple access to DB class instance from any part of the program * * This class implements the 'singleton' design pattern. * From whatever part of the program you need access to the database, * simply call the static method get() of this class: * *

 * $db = DBInstance::get();
 *
 * // use as a normal DB instance
 * $db->query("INSERT INTO foo (bar, baz) VALUES ( 5, 'foobar' )");
 *

*/ class DBInstance { /** * Returns the database instance * * @access public * @static * @return DB reference to database instance */ function get() { // our static variable, which won't lose he's value // after the function exits static $db_instance = null; if ( isset($db_instance) ) { // return already existing instance return $db_instance; } else { // instance does not exist, so create it $db_instance = DBInstance::_createInstance(); return $db_instance; } } /** * Creates new instance of database abstraction layer * * @access private * @static */ function _createInstance() { // compose the Data Source Name (DSN) // read values from configuration $dsn = array( 'phptype' => Configuration::getDatabaseType(), 'hostspec' => Configuration::getDatabaseHost(), 'username' => Configuration::getDatabaseUsername(), 'password' => Configuration::getDatabasePassword(), 'database' => Configuration::getDatabaseName() ); // compose DB interface options $options = array( // Expose errors // This might need to be set into zero in production release 'debug' => 2, // The results should be freed automatically // when there are no more rows 'autofree' => true, // DB_PORTABILITY_null_TO_EMPTY and DB_PORTABILITY_NUMROWS // have been left out, because those are Oracle-specific // and the first one (converting null's to empty strings) // is IMHO rather odd behaviour also. // I guess VIKO will never run on Oracle - so the support // for that database is admittedly left out. // // DB_PORTABILITY_RTRIM is not used because that would also // trim BLOB fields that might contain binary data - which // isn't good. 'portability' => DB_PORTABILITY_DELETE_COUNT | DB_PORTABILITY_ERRORS | DB_PORTABILITY_LOWERCASE ); // connect to the database. If this fails: die with error message. $db =& DB::connect($dsn, $options); if ( PEAR::isError($db) ) { die( $db->getMessage() ); } // The results should be returned as associative list // instead of ordinary numbered array, because normally we want to // access fields by their names, not numbers. $db->setFetchMode(DB_FETCHMODE_ASSOC); // also, the results should be returned in UTF-8 encoding $enc_res = $db->query("SET NAMES 'utf8' COLLATE 'utf8_general_ci'"); if ( PEAR::isError($enc_res) ) { die( $enc_res->getMessage() ); } return $db; } } ?>