* @link http://www.pradosoft.com/ * @copyright Copyright © 2005-2014 PradoSoft * @license http://www.pradosoft.com/license/ * @package Prado\Data\Common */ namespace Prado\Data\Common; /** * TDbMetaData is the base class for retrieving metadata information, such as * table and columns information, from a database connection. * * Use the {@link getTableInfo} method to retrieve a table information. * * @author Wei Zhuo * @package Prado\Data\Common * @since 3.1 */ abstract class TDbMetaData extends \Prado\TComponent { private $_tableInfoCache=array(); private $_connection; /** * @var array */ protected static $delimiterIdentifier = array('[', ']', '"', '`', "'"); /** * @param TDbConnection database connection. */ public function __construct($conn) { $this->_connection=$conn; } /** * @return TDbConnection database connection. */ public function getDbConnection() { return $this->_connection; } /** * Obtain database specific TDbMetaData class using the driver name of the database connection. * @param TDbConnection database connection. * @return TDbMetaData database specific TDbMetaData. */ public static function getInstance($conn) { $conn->setActive(true); //must be connected before retrieving driver name $driver = $conn->getDriverName(); switch(strtolower($driver)) { case 'pgsql': Prado::using('System.Data.Common.Pgsql.TPgsqlMetaData'); return new TPgsqlMetaData($conn); case 'mysqli': case 'mysql': Prado::using('System.Data.Common.Mysql.TMysqlMetaData'); return new TMysqlMetaData($conn); case 'sqlite': //sqlite 3 case 'sqlite2': //sqlite 2 Prado::using('System.Data.Common.Sqlite.TSqliteMetaData'); return new TSqliteMetaData($conn); case 'mssql': // Mssql driver on windows hosts case 'sqlsrv': // sqlsrv driver on windows hosts case 'dblib': // dblib drivers on linux (and maybe others os) hosts Prado::using('System.Data.Common.Mssql.TMssqlMetaData'); return new TMssqlMetaData($conn); case 'oci': Prado::using('System.Data.Common.Oracle.TOracleMetaData'); return new TOracleMetaData($conn); // case 'ibm': // Prado::using('System.Data.Common.IbmDb2.TIbmDb2MetaData'); // return new TIbmDb2MetaData($conn); default: throw new TDbException('ar_invalid_database_driver',$driver); } } /** * Obtains table meta data information for the current connection and given table name. * @param string table or view name * @return TDbTableInfo table information. */ public function getTableInfo($tableName=null) { $key = $tableName===null?$this->getDbConnection()->getConnectionString():$tableName; if(!isset($this->_tableInfoCache[$key])) { $class = $this->getTableInfoClass(); $tableInfo = $tableName===null ? new $class : $this->createTableInfo($tableName); $this->_tableInfoCache[$key] = $tableInfo; } return $this->_tableInfoCache[$key]; } /** * Creates a command builder for a given table name. * @param string table name. * @return TDbCommandBuilder command builder instance for the given table. */ public function createCommandBuilder($tableName=null) { return $this->getTableInfo($tableName)->createCommandBuilder($this->getDbConnection()); } /** * This method should be implemented by decendent classes. * @return TDbTableInfo driver dependent create builder. */ abstract protected function createTableInfo($tableName); /** * @return string TDbTableInfo class name. */ protected function getTableInfoClass() { return 'TDbTableInfo'; } /** * Quotes a table name for use in a query. * @param string $name table name * @param string $lft left delimiter * @param string $rgt right delimiter * @return string the properly quoted table name */ public function quoteTableName($name) { $name = str_replace(self::$delimiterIdentifier, '', $name); $args = func_get_args(); $rgt = $lft = isset($args[1]) ? $args[1] : ''; $rgt = isset($args[2]) ? $args[2] : $rgt; if(strpos($name, '.')===false) return $lft . $name . $rgt; $names=explode('.', $name); foreach($names as &$n) $n = $lft . $n . $rgt; return implode('.', $names); } /** * Quotes a column name for use in a query. * @param string $name column name * @param string $lft left delimiter * @param string $rgt right delimiter * @return string the properly quoted column name */ public function quoteColumnName($name) { $args = func_get_args(); $rgt = $lft = isset($args[1]) ? $args[1] : ''; $rgt = isset($args[2]) ? $args[2] : $rgt; return $lft . str_replace(self::$delimiterIdentifier, '', $name) . $rgt; } /** * Quotes a column alias for use in a query. * @param string $name column alias * @param string $lft left delimiter * @param string $rgt right delimiter * @return string the properly quoted column alias */ public function quoteColumnAlias($name) { $args = func_get_args(); $rgt = $lft = isset($args[1]) ? $args[1] : ''; $rgt = isset($args[2]) ? $args[2] : $rgt; return $lft . str_replace(self::$delimiterIdentifier, '', $name) . $rgt; } /** * Returns all table names in the database. * This method should be overridden by child classes in order to support this feature * because the default implementation simply throws an exception. * @param string $schema the schema of the tables. Defaults to empty string, meaning the current or default schema. * If not empty, the returned table names will be prefixed with the schema name. * @return array all table names in the database. */ abstract public function findTableNames($schema=''); }