21 files changed, 2883 insertions, 3 deletions
diff --git a/.gitattributes b/.gitattributes
index 89e7752e..d2a490a3 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1400,6 +1400,25 @@ framework/Collections/TStack.php -text
 framework/Configuration/Provider/TProviderBase.php -text
 framework/Configuration/Provider/TProviderException.php -text
 framework/Configuration/TProtectedConfiguration.php -text
+framework/Data/ActiveRecord/Exceptions/TActiveRecordException.php -text
+framework/Data/ActiveRecord/Exceptions/messages.txt -text
+framework/Data/ActiveRecord/TActiveRecord.php -text
+framework/Data/ActiveRecord/TActiveRecordCriteria.php -text
+framework/Data/ActiveRecord/TActiveRecordGateway.php -text
+framework/Data/ActiveRecord/TActiveRecordManager.php -text
+framework/Data/ActiveRecord/TActiveRecordStateRegistry.php -text
+framework/Data/ActiveRecord/Vendor/TDbMetaData.php -text
+framework/Data/ActiveRecord/Vendor/TDbMetaDataCommon.php -text
+framework/Data/ActiveRecord/Vendor/TDbMetaDataInspector.php -text
+framework/Data/ActiveRecord/Vendor/TMysqlColumnMetaData.php -text
+framework/Data/ActiveRecord/Vendor/TMysqlMetaData.php -text
+framework/Data/ActiveRecord/Vendor/TMysqlMetaDataInspector.php -text
+framework/Data/ActiveRecord/Vendor/TPgsqlColumnMetaData.php -text
+framework/Data/ActiveRecord/Vendor/TPgsqlMetaData.php -text
+framework/Data/ActiveRecord/Vendor/TPgsqlMetaDataInspector.php -text
+framework/Data/ActiveRecord/Vendor/TSqliteColumnMetaData.php -text
+framework/Data/ActiveRecord/Vendor/TSqliteMetaData.php -text
+framework/Data/ActiveRecord/Vendor/TSqliteMetaDataInspector.php -text
 framework/Data/TDbCommand.php -text
 framework/Data/TDbConnection.php -text
 framework/Data/TDbDataReader.php -text
diff --git a/framework/Data/ActiveRecord/Exceptions/TActiveRecordException.php b/framework/Data/ActiveRecord/Exceptions/TActiveRecordException.php
new file mode 100644
index 00000000..ec177a84
--- /dev/null
+++ b/framework/Data/ActiveRecord/Exceptions/TActiveRecordException.php
@@ -0,0 +1,39 @@
+<?php
+/**
+ * TActiveRecordException class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Exceptions
+ */
+
+/**
+ * Base exception class for Active Records.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Exceptions
+ * @since 3.1
+ */
+class TActiveRecordException extends TException
+{
+	/**
+	 * @return string path to the error message file
+	 */
+	protected function getErrorMessageFile()
+	{
+		$lang=Prado::getPreferredLanguage();
+		$path = dirname(__FILE__);
+		$msgFile=$path.'/messages-'.$lang.'.txt';
+		if(!is_file($msgFile))
+			$msgFile=$path.'/messages.txt';
+		return $msgFile;
+	}
+}
+
+class TActiveRecordConfigurationException extends TActiveRecordException
+{
+
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/Exceptions/messages.txt b/framework/Data/ActiveRecord/Exceptions/messages.txt
new file mode 100644
index 00000000..f77b2275
--- /dev/null
+++ b/framework/Data/ActiveRecord/Exceptions/messages.txt
@@ -0,0 +1,12 @@
+ar_readonly_exception						= Active Record '{0}' is read only.
+ar_object_must_be_retrieved_before_delete	= Active Record must be retrieved first before deletion.
+ar_object_must_not_be_null					= Active record object must not be null.
+ar_object_marked_for_removal				= Active record object already marked for removed.
+ar_column_meta_data_read_only				= Column meta is read only.
+ar_invalid_database_driver					= Active Record does not support database '{0}'.
+ar_invalid_finder_method					= Unsupported Active Record finder method '{0}'.
+ar_no_primary_key_found						= Table '{0}' does not contain any primary key fields.
+ar_primary_key_is_scalar					= Primary key '{1}' in table '{0}' is NOT a composite key, invalid value '{2} used.
+ar_invalid_db_connection					= Missing or invalid default database connection for ActiveRecord class '{0}', default connection is set by the DbConnection property of TActiveRecordManager.
+ar_mismatch_args_exception					= ActiveRecord finder method '{0}' expects {1} parameters but found only {2} parameters instead.
+ar_invalid_tablename_property				= ActiveRecord tablename property '{0}::${1}' must be static and not null.
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/TActiveRecord.php b/framework/Data/ActiveRecord/TActiveRecord.php
new file mode 100644
index 00000000..fd49e413
--- /dev/null
+++ b/framework/Data/ActiveRecord/TActiveRecord.php
@@ -0,0 +1,390 @@
+<?php
+/**
+ * TActiveRecord class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord
+ */
+
+Prado::using('System.Data.ActiveRecord.TActiveRecordManager');
+Prado::using('System.Data.ActiveRecord.TActiveRecordCriteria');
+
+/**
+ * Base class for active records.
+ *
+ * An active record creates an object that wraps a row in a database table
+ * or view, encapsulates the database access, and adds domain logic on that data.
+ *
+ * The essence of an Active Record is an object model of the
+ * domain (e.g. products, items) that incorporates both behavior and
+ * data in which the classes match very closely the record structure of an
+ * underlying database. Each Active Record is responsible for saving and
+ * loading to the database and also for any domain logic that acts on the data.
+ *
+ * The Active Record provides methods that do the following:
+ *  1. Construct an instance of the Active Record from a SQL result set row.
+ *  2. Construct a new instance for later insertion into the table.
+ *  3. Finder methods to wrap commonly used SQL queries and return Active Record objects.
+ *  4. Update the database and insert into it the data in the Active Record.
+ *
+ * Example:
+ * <code>
+ * class UserRecord extends TActiveRecord
+ * {
+ *     public $username; //corresponds to the fieldname in the table
+ *     public $email;
+ *
+ *     private static final $_tablename='users'; //optional table name.
+ *
+ *     //returns active record finder instance
+ *     public static function finder()
+ *     {
+ *         return self::getRecordFinder('UserRecord');
+ *     }
+ * }
+ *
+ * //create a connection and give it to the ActiveRecord manager.
+ * $conn = new TDbConnection('pgsql:host=localhost;dbname=test', 'dbuser','dbpass');
+ * TActiveRecordManager::getInstance()->setDbConnection($conn);
+ *
+ * //load the user record with username (primary key) 'admin'.
+ * $user = UserRecord::finder()->findByPk('admin');
+ * $user->email = 'admin@example.org';
+ * $user->save(); //update the 'admin' record.
+ * </code>
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord
+ * @since 3.1
+ */
+abstract class TActiveRecord extends TComponent
+{
+	/**
+	 * @var boolean true if this class is read only.
+	 */
+	private $_readOnly=false;
+
+	/**
+	 * @var TDbConnection database connection object.
+	 */
+	private $_connection;
+
+	/**
+	 * Prevent __call() method creating __sleep() when serializing.
+	 */
+	public function __sleep()
+	{
+		return array_keys(get_object_vars($this));
+	}
+
+	/**
+	 * Prevent __call() method creating __wake() when unserializing.
+	 */
+	public function __wake(){}
+
+	/**
+	 * Create a new instance of an active record with given $data. The record
+	 * can be saved to the database specified by the $connection object.
+	 *
+	 * @param array optional name value pair record data.
+	 * @param TDbConnection optional database connection this object record use.
+	 */
+	public function __construct($data=array(), $connection=null)
+	{
+		foreach($data as $name=>$value)
+			$this->$name = $value;
+		if($connection!==null)
+			$this->_connection=$connection;
+	}
+
+	/**
+	 * Gets the current Db connection, the connection object is obtained from
+	 * the TActiveRecordManager if connection is currently null.
+	 * @return TDbConnection current db connection for this object.
+	 */
+	public function getDbConnection()
+	{
+		if($this->_connection===null)
+			$this->_connection=self::getRecordManager()->getDbConnection();
+		if($this->_connection===null) //check it
+			throw new TActiveRecordException('ar_invalid_db_connection',get_class($this));
+		return $this->_connection;
+	}
+
+	/**
+	 * @param TDbConnection db connection object for this record.
+	 */
+	public function setDbConnection($connection)
+	{
+		$this->_connection=$connection;
+	}
+
+	/**
+	 * Returns the instance of a active record finder for a particular class.
+	 * @param string active record class name.
+	 * @return TActiveRecord active record finder instance.
+	 */
+	public static function getRecordFinder($class)
+	{
+		static $finders = array();
+		if(!isset($finders[$class]))
+		{
+			$f = Prado::createComponent($class);
+			$f->_readOnly=true;
+			$finders[$class]=$f;
+		}
+		return $finders[$class];
+	}
+
+	/**
+	 * Gets the record manager for this object, the default is to call
+	 * TActiveRecordManager::getInstance().
+	 * @return TActiveRecordManager default active record manager.
+	 */
+	public function getRecordManager()
+	{
+		return TActiveRecordManager::getInstance();
+	}
+
+	/**
+	 * Saves the current record to the database, insert or update is automatically determined.
+	 * @return boolean true if record was saved successfully, false otherwise.
+	 */
+	public function save()
+	{
+		$registry = $this->getRecordManager()->getObjectStateRegistry();
+		$gateway = $this->getRecordManager()->getRecordGateway();
+		if(!$this->_readOnly)
+			$this->_readOnly = $gateway->getMetaData($this)->getIsView();
+		if($this->_readOnly)
+			throw new TActiveRecordException('ar_readonly_exception',get_class($this));
+		return $registry->commit($this,$gateway);
+	}
+
+	/**
+	 * Deletes the current record from the database. Once deleted, this object
+	 * can not be saved again in the same instance.
+	 * @return boolean true if the record was deleted successfully, false otherwise.
+	 */
+	public function delete()
+	{
+		$registry = $this->getRecordManager()->getObjectStateRegistry();
+		$registry->registerRemoved($this);
+		return $this->save();
+	}
+
+	/**
+	 * Delete records by primary key. Usage:
+	 *
+	 * <code>
+	 * $finder->deleteByPk($primaryKey); //delete 1 record
+	 * $finder->deleteByPk($key1,$key2,...); //delete multiple records
+	 * $finder->deleteByPk(array($key1,$key2,...)); //delete multiple records
+	 * </code>
+	 *
+	 * For composite primary keys (determined from the table definitions):
+	 * <code>
+	 * $finder->deleteByPk(array($key1,$key2)); //delete 1 record
+	 * $finder->deleteByPk(array($key1,$key2), array($key3,$key4),...); //delete multiple records
+	 * $finder->deleteByPk(array( array($key1,$key2), array($key3,$key4), .. )); //delete multiple records
+	 * </code>
+	 *
+	 * @param unknown_type $keys
+	 * @return unknown
+	 */
+	public function deleteByPk($keys)
+	{
+		if(func_num_args() > 1)
+			$keys = func_get_args();
+		$gateway = $this->getRecordManager()->getRecordGateway();
+		return $gateway->deleteRecordsByPk($this,(array)$keys);
+	}
+
+	/**
+	 * Populate the record with data, registers the object as clean.
+	 * @param string new record name
+	 * @param array name value pair record data
+	 * @return TActiveRecord object record, null if data is empty.
+	 */
+	protected function populateObject($type, $data)
+	{
+		if(empty($data)) return null;
+		$registry = $this->getRecordManager()->getObjectStateRegistry();
+
+		//try the cache (the cache object must be clean)
+		if(!is_null($obj = $registry->getCachedInstance($data)))
+			return $obj;
+
+		//create and populate the object
+		$obj = Prado::createComponent($type);
+		foreach($data as $name => $value)
+			$obj->{$name} = $value;
+
+		$gateway = $this->getRecordManager()->getRecordGateway();
+		$obj->_readOnly = $gateway->getMetaData($this)->getIsView();
+
+		//cache it
+		return $registry->addCachedInstance($data,$obj);
+	}
+
+	/**
+	 * Find one single record that matches the criteria.
+	 *
+	 * Usage:
+	 * <code>
+	 * $finder->find('username = :name AND password = :pass', array(':name'=>$name, ':pass'=>$pass));
+	 * $finder->find('username = ? AND password = ?', array($name, $pass));
+	 * $finder->find('username = ? AND password = ?', $name, $pass);
+	 * //$criteria is of TActiveRecordCriteria
+	 * $finder->find($criteria); //the 2nd parameter for find() is ignored.
+	 * </code>
+	 *
+	 * @param string|TActiveRecordCriteria SQL condition or criteria object.
+	 * @param mixed parameter values.
+	 * @return TActiveRecord matching record object.
+	 */
+	public function find($criteria,$parameters=array())
+	{
+		if(is_string($criteria))
+		{
+			if(!is_array($parameters) && func_num_args() > 1)
+			{
+				$parameters = func_get_args();
+				array_shift($parameters);
+			}
+			$criteria=new TActiveRecordCriteria($criteria,$parameters);
+		}
+		$gateway = $this->getRecordManager()->getRecordGateway();
+		$data = $gateway->findRecordsByCriteria($this,$criteria);
+		return $this->populateObject(get_class($this), $data);
+	}
+
+	/**
+	 * Same as find() but returns an array of objects.
+	 *
+	 * @param string|TActiveRecordCriteria SQL condition or criteria object.
+	 * @param mixed parameter values.
+	 * @return array matching record objects
+	 */
+	public function findAll($criteria=null,$parameters=array())
+	{
+		if(is_string($criteria))
+		{
+			if(!is_array($parameters) && func_num_args() > 1)
+			{
+				$parameters = func_get_args();
+				array_shift($parameters);
+			}
+			$criteria=new TActiveRecordCriteria($criteria,$parameters);
+		}
+		$gateway = $this->getRecordManager()->getRecordGateway();
+		$results = array();
+		$class = get_class($this);
+		foreach($gateway->findRecordsByCriteria($this,$criteria,true)  as $data)
+			$results[] = $this->populateObject($class,$data);
+		return $results;
+	}
+
+	/**
+	 * Find one record using only the primary key or composite primary keys. Usage:
+	 *
+	 * <code>
+	 * $finder->findByPk($primaryKey);
+	 * $finder->findByPk($key1, $key2, ...);
+	 * $finder->findByPk(array($key1,$key2,...));
+	 * </code>
+	 *
+	 * @param mixed primary keys
+	 * @return TActiveRecord
+	 */
+	public function findByPk($keys)
+	{
+		if(func_num_args() > 1 && !is_array($keys))
+			$keys = func_get_args();
+		$gateway = $this->getRecordManager()->getRecordGateway();
+		$data = $gateway->findRecordByPK($this,$keys);
+		return $this->populateObject(get_class($this), $data);
+	}
+
+	/**
+	 * Find records using full SQL, returns corresponding record object.
+	 * @param string select SQL
+	 * @param array $parameters
+	 * @return array matching active records.
+	 */
+	public function findBySql($sql,$parameters=array())
+	{
+		$gateway = $this->getRecordManager()->getRecordGateway();
+		$data = $gateway->findRecordsBySql($this,$sql,$parameters);
+		$results = array();
+		$class = get_class($this);
+		foreach($gateway->findRecordsBySql($this,$sql,$parameters) as $data)
+			$results[] = $this->populateObject($class,$data);
+		return $results;
+	}
+
+	/**
+	 * Find the number of records.
+	 * @param string|TActiveRecordCriteria SQL condition or criteria object.
+	 * @param mixed parameter values.
+	 * @return int number of records.
+	 */
+	public function count($criteria=null,$parameters=array())
+	{
+		if(is_string($criteria))
+		{
+			if(!is_array($parameters) && func_num_args() > 1)
+			{
+				$parameters = func_get_args();
+				array_shift($parameters);
+			}
+			$criteria=new TActiveRecordCriteria($criteria,$parameters);
+		}
+		$gateway = $this->getRecordManager()->getRecordGateway();
+		return $gateway->countRecords($this,$criteria);
+	}
+
+	/**
+	 * Dynamic find method using parts of method name as search criteria.
+	 * Method name starting with "findBy" only returns 1 record.
+	 * Method name starting with "findAllBy" returns 0 or more records.
+	 * The condition is taken as part of the method name after "findBy" or "findAllBy".
+	 *
+	 * The following are equivalent:
+	 * <code>
+	 * $finder->findByName($name)
+	 * $finder->find('Name = ?', $name);
+	 * </code>
+	 * <code>
+	 * $finder->findByUsernameAndPassword($name,$pass);
+	 * $finder->findBy_Username_And_Password($name,$pass);
+	 * $finder->find('Username = ? AND Password = ?', $name, $pass);
+	 * </code>
+	 * <code>
+	 * $finder->findAllByAge($age);
+	 * $finder->findAll('Age = ?', $age);
+	 * </code>
+	 * @return mixed single record if method name starts with "findBy", 0 or more records
+	 * if method name starts with "findAllBy"
+	 */
+	public function __call($method,$args)
+	{
+		if($findOne = substr(strtolower($method),0,6)==='findby')
+			$condition = $method[6]==='_' ? substr($method,7) : substr($method,6);
+		else if(substr(strtolower($method,0,9)==='findallby'))
+			$condition = $method[9]==='_' ? substr($method,10) : substr($method,9);
+		else
+			throw new TActiveRecordException('ar_invalid_finder_method',$method);
+		$fields = array();
+		foreach(preg_split('/and|_and_/i',$condition) as $field)
+			$fields[] = $field.' = ?';
+		$args=count($args) === 1 && is_array($args[0]) ? $args[0] : $args;
+		if(count($fields)>count($args))
+			throw new TActiveRecordException('ar_mismatch_args_exception',$method,count($fields),count($args));
+		$criteria = new TActiveRecordCriteria(implode(' AND ',$fields),$args);
+		return $findOne ? $this->find($criteria) : $this->findAll($criteria);
+	}
+}
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/TActiveRecordCriteria.php b/framework/Data/ActiveRecord/TActiveRecordCriteria.php
new file mode 100644
index 00000000..8e7735a7
--- /dev/null
+++ b/framework/Data/ActiveRecord/TActiveRecordCriteria.php
@@ -0,0 +1,143 @@
+<?php
+/**
+ * TActiveRecordCriteria class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord
+ */
+
+/**
+ * Search criteria for Active Record.
+ *
+ * Criteria object for active record finder methods. Usage:
+ * <code>
+ * $criteria = new TActiveRecordCriteria;
+ * $criteria->Condition = 'username = :name AND password = :pass';
+ * $criteria->Parameters[':name'] = 'admin';
+ * $criteria->Parameters[':pass'] = 'prado';
+ * $criteria->OrdersBy['level'] = 'desc';
+ * $criteria->OrdersBy['name'] = 'asc';
+ * $criteria->Limit = 10;
+ * $criteria->Offset = 20;
+ * </code>
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord
+ * @since 3.1
+ */
+class TActiveRecordCriteria extends TComponent
+{
+	private $_condition;
+	private $_parameters;
+	private $_ordersBy;
+	private $_limit;
+	private $_offset;
+
+	/**
+	 * Creates a new criteria with given condition;
+	 */
+	public function __construct($condition=null,$parameters=array())
+	{
+		$this->setCondition($condition);
+		$this->_parameters=new TAttributeCollection((array)$parameters);
+		$this->_ordersBy=new TAttributeCollection;
+	}
+
+	/**
+	 * @return TAttributeCollection list of named parameters and values.
+	 */
+	public function getParameters()
+	{
+		return $this->_parameters;
+	}
+
+	/**
+	 * @param ArrayAccess named parameters.
+	 */
+	public function setParameters($value)
+	{
+		if(!(is_array($value) || $value instanceof ArrayAccess))
+			throw new TException('value must be array or ArrayAccess');
+		$this->_parameters->copyFrom($value);
+	}
+
+	/**
+	 * @return boolean true if the parameter index are string base, false otherwise.
+	 */
+	public function getIsNamedParameters()
+	{
+		foreach($this->getParameters() as $k=>$v)
+			return is_string($k);
+	}
+
+	/**
+	 * @return TAttributeCollection ordering clause.
+	 */
+	public function getOrdersBy()
+	{
+		return $this->_ordersBy;
+	}
+
+	/**
+	 * @param ArrayAccess ordering clause.
+	 */
+	public function setOrdersBy($value)
+	{
+		if(!(is_array($value) || $value instanceof ArrayAccess))
+			throw new TException('value must be array or ArrayAccess');
+		$this->_ordersBy->copyFrom($value);
+	}
+
+	/**
+	 * @return string search conditions.
+	 */
+	public function getCondition()
+	{
+		return $this->_condition;
+	}
+
+	/**
+	 * Sets the search conditions to be placed after the WHERE clause in the SQL.
+	 * @param string search conditions.
+	 */
+	public function setCondition($value)
+	{
+		$this->_condition=$value;
+	}
+
+	/**
+	 * @return int maximum number of records to return.
+	 */
+	public function getLimit()
+	{
+		return $this->_limit;
+	}
+
+	/**
+	 * @param int maximum number of records to return.
+	 */
+	public function setLimit($value)
+	{
+		$this->_limit=$value;
+	}
+
+	/**
+	 * @return int record offset.
+	 */
+	public function getOffset()
+	{
+		return $this->_offset;
+	}
+
+	/**
+	 * @param int record offset.
+	 */
+	public function setOffset($value)
+	{
+		$this->_offset=$value;
+	}
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/TActiveRecordGateway.php b/framework/Data/ActiveRecord/TActiveRecordGateway.php
new file mode 100644
index 00000000..829230fc
--- /dev/null
+++ b/framework/Data/ActiveRecord/TActiveRecordGateway.php
@@ -0,0 +1,305 @@
+<?php
+/**
+ * TActiveRecordGateway, TActiveRecordStatementType, TActiveRecordGatewayEventParameter classes file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord
+ */
+
+/**
+ * TActiveRecordGateway excutes the SQL command queries and returns the data
+ * record as arrays (for most finder methods).
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord
+ * @since 3.1
+ */
+class TActiveRecordGateway extends TComponent
+{
+	private $_manager;
+	private $_tables=array();
+
+	/**
+	 * Property name for optional table name in TActiveRecord.
+	 */
+	const PROPERTY_TABLE_NAME='_tablename';
+
+	/**
+	 * Record gateway constructor.
+	 * @param TActiveRecordManager $manager
+	 */
+	public function __construct(TActiveRecordManager $manager)
+	{
+		$this->_manager=$manager;
+	}
+
+	/**
+	 * @return TActiveRecordManager record manager.
+	 */
+	protected function getManager()
+	{
+		return $this->_manager;
+	}
+
+	/**
+	 * Gets the table name from the $_tablename property of the active record
+	 * class if defined, otherwise use the class name as table name.
+	 * @param TActiveRecord active record instance
+	 * @return string table name for the given record class.
+	 */
+	public function getTableName(TActiveRecord $record)
+	{
+		$class = new ReflectionClass($record);
+		if($class->hasProperty(self::PROPERTY_TABLE_NAME))
+		{
+			$value = $class->getProperty(self::PROPERTY_TABLE_NAME)->getValue();
+			if($value===null)
+				throw new TActiveRecordException('ar_invalid_tablename_property',
+					get_class($record),self::PROPERTY_TABLE_NAME);
+			return $value;
+		}
+		else
+			return strtolower(get_class($record));
+	}
+
+	/**
+	 * Gets the meta data for given database and table.
+	 */
+	public function getMetaData(TActiveRecord $record)
+	{
+		$type=get_class($record);
+		if(!isset($this->_tables[$type]))
+		{
+			$conn = $record->getDbConnection();
+			$inspector = $this->getManager()->getTableInspector($conn);
+			$table = $this->getTableName($record);
+			$this->_tables[$type] = $inspector->getTableMetaData($table);
+		}
+		return $this->_tables[$type];
+	}
+
+	/**
+	 * @param array table meta data.
+	 */
+	public function setAllMetaData($data)
+	{
+		$this->_tables=$data;
+	}
+
+	/**
+	 * @return array all table meta data.
+	 */
+	public function getAllMetaData()
+	{
+		return $this->_tables;
+	}
+
+	/**
+	 * Returns record data matching the given primary key(s). If the table uses
+	 * composite key, specify the name value pairs as an array.
+	 * @param TActiveRecord active record instance.
+	 * @param array primary name value pairs
+	 * @return array record data
+	 */
+	public function findRecordByPK(TActiveRecord $record,$keys)
+	{
+		$meta = $this->getMetaData($record);
+		$command = $meta->getFindByPkCommand($record->getDbConnection(),$keys);
+		$this->raiseCommandEvent(TActiveRecordStatementType::Select,$command,$record,$keys);
+		return $meta->postQueryRow($command->queryRow());
+	}
+
+	/**
+	 * Returns record data matching the given critera. If $iterator is true, it will
+	 * return multiple rows as TDbDataReader otherwise it returns the <b>first</b> row data.
+	 * @param TActiveRecord active record finder instance.
+	 * @param TActiveRecordCriteria search criteria.
+	 * @param boolean true to return multiple rows as iterator, false returns first row.
+	 * @return mixed matching data.
+	 */
+	public function findRecordsByCriteria(TActiveRecord $record, $criteria, $iterator=false)
+	{
+		$meta = $this->getMetaData($record);
+		$command = $meta->getFindByCriteriaCommand($record->getDbConnection(),$criteria);
+		$this->raiseCommandEvent(TActiveRecordStatementType::Select,$command,$record,$criteria);
+		return $iterator ? $meta->postQuery($command->query()) : $meta->postQueryRow($command->queryRow());
+	}
+
+	/**
+	 * Return record data from sql query.
+	 * @param TActiveRecord active record finder instance.
+	 * @param string SQL string
+	 * @param array query parameters.
+	 * @return TDbDataReader result iterator.
+	 */
+	public function findRecordsBySql(TActiveRecord $record, $sql,$parameters=array())
+	{
+		$meta = $this->getMetaData($record);
+		$command = $meta->getFindBySqlCommand($record->getDbConnection(),$sql,$parameters);
+		$this->raiseCommandEvent(TActiveRecordStatementType::Select,$command,$record,$parameters);
+		return $meta->postQuery($command->query());
+	}
+
+	/**
+	 * Returns the number of records that match the given criteria.
+	 * @param TActiveRecord active record finder instance.
+	 * @param TActiveRecordCriteria search criteria
+	 * @return int number of records.
+	 */
+	public function countRecords(TActiveRecord $record, $criteria)
+	{
+		$meta = $this->getMetaData($record);
+		$command = $meta->getCountRecordsCommand($record->getDbConnection(),$criteria);
+		$this->raiseCommandEvent(TActiveRecordStatementType::Select,$command,$record,$criteria);
+		return intval($command->queryScalar());
+	}
+
+	/**
+	 * Insert a new record.
+	 * @param TActiveRecord new record.
+	 * @return int number of rows affected.
+	 */
+	public function insert(TActiveRecord $record)
+	{
+		$meta = $this->getMetaData($record);
+		$command = $meta->getInsertCommand($record->getDbConnection(),$record);
+		$this->raiseCommandEvent(TActiveRecordStatementType::Insert,$command,$record);
+		$rowsAffected = $command->execute();
+		if($rowsAffected===1)
+			$meta->updatePostInsert($record->getDbConnection(),$record);
+		return $rowsAffected;
+	}
+
+	/**
+	 * Update the record.
+	 * @param TActiveRecord dirty record.
+	 * @return int number of rows affected.
+	 */
+	public function update(TActiveRecord $record)
+	{
+		$meta = $this->getMetaData($record);
+		$command = $meta->getUpdateCommand($record->getDbConnection(),$record);
+		$this->raiseCommandEvent(TActiveRecordStatementType::Update,$command,$record);
+		return $command->execute();
+	}
+
+	/**
+	 * Delete the record.
+	 * @param TActiveRecord record to be deleted.
+	 * @return int number of rows affected.
+	 */
+	public function delete(TActiveRecord $record)
+	{
+		$meta = $this->getMetaData($record);
+		$command = $meta->getDeleteCommand($record->getDbConnection(),$record);
+		$this->raiseCommandEvent(TActiveRecordStatementType::Delete,$command,$record);
+		return $command->execute();
+	}
+
+	/**
+	 * Delete multiple records using primary keys.
+	 * @param TActiveRecord finder instance.
+	 * @return int number of rows deleted.
+	 */
+	public function deleteRecordsByPk(TActiveRecord $record, $keys)
+	{
+		$meta = $this->getMetaData($record);
+		$command = $meta->getDeleteByPkCommand($record->getDBConnection(),$keys);
+		$this->raiseCommandEvent(TActiveRecordStatementType::Delete,$command,$record,$keys);
+		return $command->execute();
+	}
+
+	/**
+	 * Raise the corresponding command event, insert, update, delete or select.
+	 * @param string command type
+	 * @param TDbCommand sql command to be executed.
+	 * @param TActiveRecord active record
+	 * @param mixed data for the command.
+	 */
+	protected function raiseCommandEvent($type,$command,$record=null,$data=null)
+	{
+		$param = new TActiveRecordGatewayEventParameter($type,$command,$record,$data);
+		$manager = $record->getRecordManager();
+		$event = 'on'.$type;
+		$manager->{$event}($param);
+	}
+}
+
+/**
+ * Command statement types.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord
+ * @since 3.1
+ */
+class TActiveRecordStatementType
+{
+	const Insert='Insert';
+	const Update='Update';
+	const Delete='Delete';
+	const Select='Select';
+}
+
+/**
+ * Active Record command event parameter.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord
+ * @since 3.1
+ */
+class TActiveRecordGatewayEventParameter extends TActiveRecordEventParameter
+{
+	private $_type;
+	private $_command;
+	private $_record;
+	private $_data;
+
+	/**
+	 * New gateway command event parameter.
+	 */
+	public function __construct($type,$command,$record=null,$data=null)
+	{
+		$this->_type=$type;
+		$this->_command=$command;
+		$this->_data=$data;
+		$this->_record=$record;
+	}
+
+	/**
+	 * @return string TActiveRecordStateType
+	 */
+	public function getType()
+	{
+		return $this->_type;
+	}
+
+	/**
+	 * @return TDbCommand command to be executed.
+	 */
+	public function getCommand()
+	{
+		return $this->_command;
+	}
+
+	/**
+	 * @return TActiveRecord active record.
+	 */
+	public function getRecord()
+	{
+		return $this->_record;
+	}
+
+	/**
+	 * @return mixed command data.
+	 */
+	public function getData()
+	{
+		return $this->_data;
+	}
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/TActiveRecordManager.php b/framework/Data/ActiveRecord/TActiveRecordManager.php
new file mode 100644
index 00000000..cff02988
--- /dev/null
+++ b/framework/Data/ActiveRecord/TActiveRecordManager.php
@@ -0,0 +1,213 @@
+<?php
+/**
+ * TActiveRecordManager and TActiveRecordEventParameter classes file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord
+ */
+
+Prado::using('System.Data.TDbConnection');
+Prado::using('System.Data.ActiveRecord.Exceptions.TActiveRecordException');
+Prado::using('System.Data.ActiveRecord.TActiveRecordGateway');
+Prado::using('System.Data.ActiveRecord.TActiveRecordStateRegistry');
+
+/**
+ * TActiveRecordManager provides the default DB connection, default object state
+ * registry, default active record gateway, and table meta data inspector.
+ *
+ * You can provide a different registry by overriding the createObjectStateRegistry() method.
+ * Similarly, override createRecordGateway() for default gateway and override
+ * createMetaDataInspector() for meta data inspector.
+ *
+ * The default connection can be set as follows:
+ * <code>
+ * TActiveRecordManager::getInstance()->setDbConnection($conn);
+ * </code>
+ * All new active record created after setting the
+ * {@link DbConnection setDbConnection()} will use that connection.
+ *
+ * The {@link OnInsert onInsert()}, {@link OnUpdate onUpdate()},
+ * {@link OnDelete onDelete()} and {@link onSelect onSelect()} events are raised
+ * <b>before</b> their respective command are executed.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord
+ * @since 3.1
+ */
+class TActiveRecordManager extends TComponent
+{
+	private $_objectRegistry;
+	private $_gateway;
+	private $_meta=array();
+	private $_connection;
+
+	/**
+	 * @param TDbConnection default database connection
+	 */
+	public function setDbConnection($conn)
+	{
+		$this->_connection=$conn;
+	}
+
+	/**
+	 * @return TDbConnection default database connection
+	 */
+	public function getDbConnection()
+	{
+		return $this->_connection;
+	}
+
+	/**
+	 * @return TActiveRecordManager static instance of record manager.
+	 */
+	public static function getInstance()
+	{
+		static $instance;
+		if($instance===null)
+			$instance = new self;
+		return $instance;
+	}
+
+	/**
+	 * @return TActiveRecordStateRegistry record object registry.
+	 */
+	public function getObjectStateRegistry()
+	{
+		if(is_null($this->_objectRegistry))
+			$this->_objectRegistry = $this->createObjectStateRegistry();
+		return $this->_objectRegistry;
+	}
+
+	/**
+	 * @return TActiveRecordStateRegistry default object registry.
+	 */
+	protected function createObjectStateRegistry()
+	{
+		return new TActiveRecordStateRegistry();
+	}
+
+	/**
+	 * @return TActiveRecordGateway record gateway.
+	 */
+	public function getRecordGateway()
+	{
+		if(is_null($this->_gateway))
+			$this->_gateway = $this->createRecordGateway();
+		return $this->_gateway;
+	}
+
+	/**
+	 * @return TActiveRecordGateway default record gateway.
+	 */
+	protected function createRecordGateway()
+	{
+		return new TActiveRecordGateway($this);
+	}
+
+	/**
+	 * Get table meta data for particular database and table.
+	 * @param TDbConnection database connection.
+	 * @return TDbMetaDataInspector table meta inspector
+	 */
+	public function getTableInspector(TDbConnection $conn)
+	{
+		$database = $conn->getConnectionString();
+		if(!isset($this->_meta[$database]))
+			$this->_meta[$database] = $this->createMetaDataInspector($conn);
+		return $this->_meta[$database];
+	}
+
+	/**
+	 * Create an instance of a database meta inspector corresponding to the
+	 * given database vendor specified by the $driver parameter.
+	 * @param TDbConnection database connection
+	 * @return TDbMetaDataInspector table meta inspector
+	 */
+	protected function createMetaDataInspector($conn)
+	{
+		$conn->setActive(true); //must be connected before retrieving driver name!
+		$driver = $conn->getDriverName();
+		switch(strtolower($driver))
+		{
+			case 'pgsql':
+				Prado::using('System.Data.ActiveRecord.Vendor.TPgsqlMetaDataInspector');
+				return new TPgsqlMetaDataInspector($conn);
+			case 'mysqli':
+			case 'mysql':
+				Prado::using('System.Data.ActiveRecord.Vendor.TMysqlMetaDataInspector');
+				return new TMysqlMetaDataInspector($conn);
+			case 'sqlite': //sqlite 3
+			case 'sqlite2': //sqlite 2
+				Prado::using('System.Data.ActiveRecord.Vendor.TSqliteMetaDataInspector');
+				return new TSqliteMetaDataInspector($conn);
+			default:
+				throw new TActiveRecordConfigurationException(
+					'ar_invalid_database_driver',$driver);
+		}
+	}
+
+	/**
+	 * This method is invoked before the object is inserted into the database.
+	 * The method raises 'OnInsert' event.
+	 * If you override this method, be sure to call the parent implementation
+	 * so that the event handlers can be invoked.
+	 * @param TActiveRecordEventParameter event parameter to be passed to the event handlers
+	 */
+	public function onInsert($param)
+	{
+		$this->raiseEvent('OnInsert', $this, $param);
+	}
+
+	/**
+	 * This method is invoked before the object is deleted from the database.
+	 * The method raises 'OnDelete' event.
+	 * If you override this method, be sure to call the parent implementation
+	 * so that the event handlers can be invoked.
+	 * @param TActiveRecordEventParameter event parameter to be passed to the event handlers
+	 */
+	public function onDelete($param)
+	{
+		$this->raiseEvent('OnDelete', $this, $param);
+	}
+
+	/**
+	 * This method is invoked before the object data is updated in the database.
+	 * The method raises 'OnUpdate' event.
+	 * If you override this method, be sure to call the parent implementation
+	 * so that the event handlers can be invoked.
+	 * @param TActiveRecordEventParameter event parameter to be passed to the event handlers
+	 */
+	public function onUpdate($param)
+	{
+		$this->raiseEvent('OnUpdate', $this, $param);
+	}
+
+	/**
+	 * This method is invoked before any select query is executed on the database.
+	 * The method raises 'OnSelect' event.
+	 * If you override this method, be sure to call the parent implementation
+	 * so that the event handlers can be invoked.
+	 * @param TActiveRecordEventParameter event parameter to be passed to the event handlers
+	 */
+	public function onSelect($param)
+	{
+		$this->raiseEvent('OnSelect', $this, $param);
+	}
+}
+
+/**
+ * TActiveRecordEventParameter class.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord
+ * @since 3.1
+ */
+class TActiveRecordEventParameter extends TEventParameter
+{
+
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/TActiveRecordStateRegistry.php b/framework/Data/ActiveRecord/TActiveRecordStateRegistry.php
new file mode 100644
index 00000000..4493d4cb
--- /dev/null
+++ b/framework/Data/ActiveRecord/TActiveRecordStateRegistry.php
@@ -0,0 +1,262 @@
+<?php
+/**
+ * TActiveRecordStateRegistry class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord
+ */
+
+/**
+ * Active record Unit of Work class and Identity Map.
+ *
+ * Maintains a list of objects affected by a business transaction and
+ * coordinates the writing out of changes and the resolution of concurrency problems.
+ *
+ * This registry keeps track of everything you do during a business transaction
+ * that can affect the database. When you're done, it figures out everything that
+ * needs to be done to alter the database as a result of your work.
+ *
+ * The object can only be in one of the four states: "new", "clean", "dirty" or "removed".
+ * A "new" object is one that is created not by loading the record from database.
+ * A "clean" object is one that is created by loading the record from datase.
+ * A "dirty" object is one that is marked as dirty or a "clean" object that has
+ * its internal state altered (done by using == object comparision).
+ * A "removed" object is one that is marked for deletion.
+ *
+ * See the "Active Record Object States.png" in the docs directory for state
+ * transition diagram.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord
+ * @since 3.1
+ */
+class TActiveRecordStateRegistry
+{
+	private $_cleanObjects=array();
+	private $_removedObjects;
+	private $_cachedObjects=array();
+	/**
+	 * Initialize the registry.
+	 */
+	public function __construct()
+	{
+		$this->_removedObjects = new TList;
+	}
+
+	/**
+	 * Get the cached object for given type and row data. The cached object
+	 * must also be clean.
+	 * @param mixed row data fetched
+	 * @return TActiveRecord cached object if found, null otherwise.
+	 */
+	public function getCachedInstance($data)
+	{
+		$key = $this->getObjectDataKey($data);
+		if(isset($this->_cachedObjects[$key]))
+		{
+			$obj = $this->_cachedObjects[$key];
+			if($this->getIsCleanObject($obj))
+				return $obj;
+		}
+	}
+
+	/**
+	 * Cache the object that corresponding to the fetched row data.
+	 * @param mixed row data fetched.
+	 * @param TActiveRecord object to be cached.
+	 * @return TActiveRecord cached object.
+	 */
+	public function addCachedInstance($data,$obj)
+	{
+		$key = $this->getObjectDataKey($data);
+		$this->registerClean($obj);
+		$this->_cachedObjects[$key]=$obj;
+		return $obj;
+	}
+
+	/**
+	 * @return string hash of the data.
+	 */
+	protected function getObjectDataKey($data)
+	{
+		return sprintf('%x',crc32(serialize($data)));
+	}
+
+	/**
+	 * Ensure that object is not null.
+	 */
+	protected function assertNotNull($obj)
+	{
+		if(is_null($obj))
+			throw new TActiveRecordException('ar_object_must_not_be_null');
+	}
+
+	/**
+	 * Register the object for deletion, when the object invokes its delete() method
+	 * the corresponding row in the database is deleted.
+	 * @param TActiveRecord existing active record.
+	 * @throws TActiveRecordException if object is null.
+	 */
+	public function registerRemoved($obj)
+	{
+		$this->assertNotNull($obj);
+		$found=false;
+		foreach($this->_cleanObjects as $i=>$cache)
+		{
+			if($cache[0]===$obj)
+			{
+				unset($this->_cleanObjects[$i]);
+				$found=true;
+			}
+		}
+		if(!$found)
+			throw new TActiveRecordException('ar_object_must_be_retrieved_before_delete');
+		if(!$this->_removedObjects->contains($obj))
+			$this->_removedObjects->add($obj);
+	}
+
+	/**
+	 * Register a clean object attached to a specific data that was used to
+	 * populate the object. This acts as an object cache.
+	 * @param TActiveRecord new clean object.
+	 */
+	public function registerClean($obj)
+	{
+		$this->removeCleanOrDirty($obj);
+		if($this->getIsRemovedObject($obj))
+			throw new TActiveRecordException('ar_object_marked_for_removal');
+		$this->_cleanObjects[] = array($obj, clone($obj));
+	}
+
+	/**
+	 * Remove the object from dirty state.
+	 * @param TActiveRecord object to remove.
+	 */
+	protected function removeDirty($obj)
+	{
+		$this->assertNotNull($obj);
+		foreach($this->_cleanObjects as $i=>$cache)
+			if($cache[0]===$obj && $obj != $cache[1])
+				unset($this->_cleanObjects[$i]);
+	}
+
+	/**
+	 * Remove object from clean state.
+	 * @param TActiveRecord object to remove.
+	 */
+	protected function removeClean($obj)
+	{
+		$this->assertNotNull($obj);
+		foreach($this->_cleanObjects as $i=>$cache)
+			if($cache[0]===$obj && $obj == $cache[1])
+				unset($this->_cleanObjects[$i]);
+	}
+
+	/**
+	 * Remove object from dirty and clean state.
+	 * @param TActiveRecord object to remove.
+	 */
+	protected function removeCleanOrDirty($obj)
+	{
+		$this->assertNotNull($obj);
+		foreach($this->_cleanObjects as $i=>$cache)
+			if($cache[0]===$obj)
+				unset($this->_cleanObjects[$i]);
+	}
+
+	/**
+	 * Remove object from removed state.
+	 * @param TActiveRecord object to remove.
+	 */
+	protected function removeRemovedObject($obj)
+	{
+		$this->_removedObjects->remove($obj);
+	}
+
+	/**
+	 * Test whether an object is dirty or has been modified.
+	 * @param TActiveRecord object to test.
+	 * @return boolean true if the object is dirty, false otherwise.
+	 */
+	public function getIsDirtyObject($obj)
+	{
+		foreach($this->_cleanObjects as $cache)
+			if($cache[0] === $obj)
+				return $obj != $cache[1];
+		return false;
+	}
+
+	/**
+	 * Test whether an object is in the clean state.
+	 * @param TActiveRecord object to test.
+	 * @return boolean true if object is clean, false otherwise.
+	 */
+	public function getIsCleanObject($obj)
+	{
+		foreach($this->_cleanObjects as $cache)
+			if($cache[0] === $obj)
+				return $obj == $cache[1];
+		return false;
+	}
+
+	/**
+	 * Test whether an object is a new instance.
+	 * @param TActiveRecord object to test.
+	 * @return boolean true if object is newly created, false otherwise.
+	 */
+	public function getIsNewObject($obj)
+	{
+		if($this->getIsRemovedObject($obj)) return false;
+		foreach($this->_cleanObjects as $cache)
+			if($cache[0] === $obj)
+				return false;
+		return true;
+	}
+
+	/**
+	 * Test whether an object is marked for deletion.
+	 * @param TActiveRecord object to test.
+	 * @return boolean true if object is marked for deletion, false otherwise.
+	 */
+	public function getIsRemovedObject($obj)
+	{
+		return $this->_removedObjects->contains($obj);
+	}
+
+	/**
+	 * Commit the object to database:
+	 *   * a new record is inserted if the object is new, object becomes clean.
+	 *   * the record is updated if the object is dirty, object becomes clean.
+	 *   * the record is deleted if the object is marked for removal.
+	 *
+	 * @param TActiveRecord record object.
+	 * @param TActiveRecordGateway database gateway
+	 * @return boolean true if commit was successful, false otherwise.
+	 */
+	public function commit($record,$gateway)
+	{
+		$rowsAffected=0;
+
+		if($this->getIsRemovedObject($record))
+		{
+			$rowsAffected = $gateway->delete($record);
+			if($rowsAffected===1)
+				$this->removeRemovedObject($record);
+		}
+		else
+		{
+			if($this->getIsDirtyObject($record))
+				$rowsAffected = $gateway->update($record);
+			else if($this->getIsNewObject($record))
+				$rowsAffected = $gateway->insert($record);
+
+			if($rowsAffected===1)
+				$this->registerClean($record);
+		}
+		return $rowsAffected===1;
+	}
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/Vendor/TDbMetaData.php b/framework/Data/ActiveRecord/Vendor/TDbMetaData.php
new file mode 100644
index 00000000..490515f6
--- /dev/null
+++ b/framework/Data/ActiveRecord/Vendor/TDbMetaData.php
@@ -0,0 +1,363 @@
+<?php
+/**
+ * TDbMetaData class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ */
+
+/**
+ * Table meta data for Active Record.
+ *
+ * TDbMetaData is the base class for database vendor specific that builds
+ * the appropriate database commands for active record finder and commit methods.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ * @since 3.1
+ */
+abstract class TDbMetaData extends TComponent
+{
+	private $_primaryKeys=array();
+	private $_foreignKeys=array();
+	private $_columns=array();
+	private $_table;
+	private $_isView=false;
+
+	/**
+	 * Initialize the meta data.
+	 * @param string table name
+	 * @param array name value pair of column meta data in the table
+	 * @param array primary key field names
+	 * @param array foriegn key field meta data.
+	 */
+	public function __construct($table, $cols, $pk, $fk=array(),$view=false)
+	{
+		$this->_table=$table;
+		$this->_columns=$cols;
+		$this->_primaryKeys=$pk;
+		$this->_foreignKeys=$fk;
+		$this->_isView=$view;
+	}
+
+	public function getIsView()
+	{
+		return $this->_isView;
+	}
+
+	/**
+	 * @return string table name
+	 */
+	public function getTableName()
+	{
+		return $this->_table;
+	}
+
+	/**
+	 * @return array primary key field names.
+	 */
+	public function getPrimaryKeys()
+	{
+		return $this->_primaryKeys;
+	}
+
+	/**
+	 * @return array foreign key meta data.
+	 */
+	public function getForeignKeys()
+	{
+		return $this->_foreignKeys;
+	}
+
+	/**
+	 * @return array name value pair column meta data
+	 */
+	public function getColumns()
+	{
+		return $this->_columns;
+	}
+
+	/**
+	 * @param unknown_type $name
+	 */
+	public function getColumn($name)
+	{
+		return $this->_columns[$name];
+	}
+
+	/**
+	 * Post process the rows after returning from a 1 row query.
+	 * @param mixed row data, may be null.
+	 * @return mixed processed rows.
+	 */
+	public function postQueryRow($row)
+	{
+		return $row;
+	}
+
+	/**
+	 * Post process the rows after returning from a 1 row query.
+	 * @param TDbDataReader multiple row data
+	 * @return array post processed data.
+	 */
+	public function postQuery($rows)
+	{
+		return $rows;
+	}
+
+	/**
+	 * @return string command separated list of all fields in the table, field names are quoted.
+	 */
+	protected function getSelectionColumns()
+	{
+		$columns = array();
+		foreach($this->getColumns() as $column)
+			$columns[] = $column->getName();
+		return implode(', ', $columns);
+	}
+
+	/**
+	 * Construct search criteria using primary key names
+	 * @return string SQL string for used after WHERE statement.
+	 */
+	protected function getPrimaryKeyCriteria()
+	{
+		if(count($this->getPrimaryKeys())===0)
+			throw new TActiveRecordException('ar_no_primary_key_found',$this->getTableName());
+		$criteria=array();
+		foreach($this->getPrimaryKeys() as $key)
+			$criteria[] = $this->getColumn($key)->getName(). ' = :'.$key;
+		return implode(' AND ', $criteria);
+	}
+
+	/**
+	 * Bind a list of variables in the command. The named parameters is taken
+	 * from the values of the $keys parameter. The bind value is taken from the
+	 * $values parameter using the index taken from the each value of $keys array.
+	 * @param TDbCommand SQL database command
+	 * @param array named parameters
+	 * @param array binding values (index should match that of $keys)
+	 */
+	protected function bindArrayKeyValues($command, $keys, $values)
+	{
+		if(!is_array($values)) $values = array($values);
+		foreach($keys as $i => $key)
+		{
+			$value = isset($values[$i]) ? $values[$i] : $values[$key];
+			$command->bindValue(':'.$key, $value);
+		}
+		$command->prepare();
+	}
+
+	/**
+	 * Returns a list of name value pairs from the object.
+	 * @param array named parameters
+	 * @param TActiveRecord record object
+	 * @return array name value pairs.
+	 */
+	protected function getObjectKeyValues($keys, $object)
+	{
+		$properties = array();
+		foreach($keys as $key)
+			$properties[$key] = $object->{$key};
+		return $properties;
+	}
+
+	/**
+	 * Gets the columns that can be inserted into the database.
+	 * @param TActiveRecord record object to be inserted.
+	 * @return array name value pairs of fields to be added.
+	 */
+	protected function getInsertableColumns($record)
+	{
+		$columns = array();
+		foreach($this->getColumns() as $name=>$column)
+		{
+			$value = $record->{$name};
+			if($column->getNotNull() && $value===null && !$column->getIsPrimaryKey())
+			{
+				throw new TActiveRecordException(
+					'ar_value_must_not_be_null', get_class($record),
+					$this->getTableName(), $name);
+			}
+			if($value!==null)
+				$columns[$name] = $value;
+		}
+		return $columns;
+	}
+
+	/**
+	 * Gets the columns that will be updated, it exculdes primary key columns
+	 * and record properties that are null.
+	 * @param TActiveRecord record object with new data for update.
+	 * @return array name value pairs of fields to be updated.
+	 */
+	protected function getUpdatableColumns($record)
+	{
+		$columns = array();
+		foreach($this->getColumns() as $name => $column)
+		{
+			$value = $record->{$name};
+			if(!$column->getIsPrimaryKey() && $value !== null)
+				$columns[$name] = $value;
+		}
+		return $columns;
+	}
+
+	/**
+	 * Gets a comma delimited string of name parameters for update.
+x	 * @param array name value pairs of columns for update.
+	 * @return string update named parameter string.
+	 */
+	protected function getUpdateBindings($columns)
+	{
+		$fields = array();
+		foreach($columns as $name=>$value)
+			$fields[] = $this->getColumn($name)->getName(). '= :'.$name;
+		return implode(', ', $fields);
+	}
+
+	/**
+	 * Create a new database command based on the given $sql and bind the
+	 * named parameters given by $names with values corresponding in $values.
+	 * @param TDbConnection database connection.
+	 * @param string SQL string.
+	 * @param array named parameters
+	 * @param array matching named parameter values
+	 * @return TDbCommand binded command, ready for execution.
+	 */
+	protected function createBindedCommand($conn, $sql, $names,$values)
+	{
+		$conn->setActive(true);
+		$command = $conn->createCommand($sql);
+		$this->bindArrayKeyValues($command,$names,$values);
+		return $command;
+	}
+
+	/**
+	 * Creates a new database command and bind the values from the criteria object.
+	 *
+	 * @param TDbConnection database connection.
+	 * @param string SQL string.
+	 * @param TActiveRecordCriteria search criteria
+	 * @return TDbCommand binded command.
+	 */
+	protected function createCriteriaBindedCommand($conn,$sql,$criteria)
+	{
+		$conn->setActive(true);
+		$command = $conn->createCommand($sql);
+		if($criteria!==null)
+		{
+			if($criteria->getIsNamedParameters())
+			{
+				foreach($criteria->getParameters() as $name=>$value)
+					$command->bindValue($name,$value);
+			}
+			else
+			{
+				$index=1;
+				foreach($criteria->getParameters() as $value)
+					$command->bindValue($index++,$value);
+			}
+		}
+		$command->prepare();
+		return $command;
+	}
+
+	/**
+	 * Bind parameter values.
+	 */
+	protected function bindParameterValues($conn,$command,$parameters)
+	{
+		$index=1;
+		foreach($parameters as $key=>$value)
+		{
+			if(is_string($key))
+				$command->bindValue($key,$value);
+			else
+				$command->bindValue($index++,$value);
+		}
+		$command->prepare();
+	}
+
+	/**
+	 * Gets the comma delimited string of fields name for insert command.
+	 */
+	protected function getInsertColumNames($columns)
+	{
+		$fields = array();
+		foreach($columns as $name=>$column)
+			$fields[] = $this->getColumn($name)->getName();
+		return implode(', ', $fields);
+	}
+
+	/**
+	 * Gets the comma delimited string of name bindings for insert command.
+	 */
+	protected function getInsertColumnValues($columns)
+	{
+		$fields = array();
+		foreach(array_keys($columns) as $column)
+			$fields[] = ':'.$column;
+		return implode(', ', $fields);
+	}
+
+	/**
+	 * @param TDbConnection database connection
+	 * @param array primary key values.
+	 * @return string delete criteria for multiple scalar primary keys.
+	 */
+	protected function getDeleteInPkCriteria($conn, $keys)
+	{
+		$pk = $this->getPrimaryKeys();
+		$column = $this->getColumn($pk[0])->getName();
+		$values = array();
+		foreach($keys as $key)
+		{
+			if(is_array($key))
+			{
+				throw new TActiveRecordException('ar_primary_key_is_scalar',
+					$this->getTableName(),$column,'array('.implode(', ',$key).')');
+			}
+			$values[] = $conn->quoteString($key);
+		}
+		$pks = implode(', ', $values);
+		return "$column IN ($pks)";
+	}
+
+	/**
+	 * @param TDbConnection database connection
+	 * @param array primary key values.
+	 * @return string delete criteria for multiple composite primary keys.
+	 */
+	protected function getDeleteMultiplePkCriteria($conn,$pks)
+	{
+		//check for 1 set composite keys
+		if(count($pks)>0 && !is_array($pks[0]))
+			$pks = array($pks);
+		$conditions=array();
+		foreach($pks as $keys)
+			$conditions[] = $this->getDeleteCompositeKeyCondition($conn,$keys);
+		return implode(' OR ', $conditions);
+	}
+
+	/**
+	 * @return string delete criteria for 1 composite key.
+	 */
+	protected function getDeleteCompositeKeyCondition($conn,$keys)
+	{
+		$condition=array();
+		$index = 0;
+		foreach($this->getPrimarykeys() as $pk)
+		{
+			$name = $this->getColumn($pk)->getName();
+			$value = isset($keys[$pk]) ? $keys[$pk] : $keys[$index];
+			$condition[] = "$name = ".$conn->quoteString($value);
+			$index++;
+		}
+		return '('.implode(' AND ', $condition).')';
+	}
+}
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/Vendor/TDbMetaDataCommon.php b/framework/Data/ActiveRecord/Vendor/TDbMetaDataCommon.php
new file mode 100644
index 00000000..69f49dc1
--- /dev/null
+++ b/framework/Data/ActiveRecord/Vendor/TDbMetaDataCommon.php
@@ -0,0 +1,175 @@
+<?php
+/**
+ * TDbMetaDataCommon class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ */
+
+Prado::using('System.Data.ActiveRecord.Vendor.TDbMetaData');
+
+/**
+ * Common database command: insert, update, select and delete.
+ *
+ * Base class for database specific insert, update, select and delete command builder.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ * @since 3.1
+ */
+abstract class TDbMetaDataCommon extends TDbMetaData
+{
+	/**
+	 * SQL database command for finding the record by primary keys.
+	 * @param TDbConnection database connection.
+	 * @param array primary keys name value pairs.
+	 * @return TDbCommand find by primary key command.
+	 */
+	public function getFindByPkCommand($conn,$keys)
+	{
+		$columns = $this->getSelectionColumns();
+		$primaryKeys = $this->getPrimaryKeyCriteria();
+		$table = $this->getTableName();
+		$sql = "SELECT {$columns} FROM {$table} WHERE {$primaryKeys}";
+		$command = $this->createBindedCommand($conn, $sql, $this->getPrimaryKeys(), $keys);
+		return $command;
+	}
+
+	/**
+	 * SQL database command for finding records using a criteria object.
+	 * @param TDbConnection database connection.
+	 * @param TActiveRecordCriteria criteria object
+	 * @return TDbCommand find by criteria command.
+	 */
+	public function getFindByCriteriaCommand($conn, $criteria=null)
+	{
+		$columns = $this->getSelectionColumns();
+		$conditions = $criteria!==null?$this->getSqlFromCriteria($criteria) : '';
+		$table = $this->getTableName();
+		$sql = "SELECT {$columns} FROM {$table} {$conditions}";
+		return $this->createCriteriaBindedCommand($conn,$sql, $criteria);
+	}
+
+	/**
+	 * Command to count the number of record matching the criteria.
+	 * @param TDbConnection database connection.
+	 * @param TActiveRecordCriteria criteria object
+	 * @return TDbCommand count command.
+	 * 	 */
+	public function getCountRecordsCommand($conn, $criteria)
+	{
+		$columns = $this->getSelectionColumns();
+		$conditions = $this->getSqlFromCriteria($criteria);
+		$table = $this->getTableName();
+		$sql = "SELECT count(*) FROM {$table} {$conditions}";
+		return $this->createCriteriaBindedCommand($conn,$sql, $criteria);
+	}
+
+	abstract protected function getSqlFromCriteria(TActiveRecordCriteria $criteria);
+
+	/**
+	 * Sql command with parameters binded.
+	 * @param TDbConnection database connection.
+	 * @param string sql query.
+	 * @param array parameters to be bound
+	 * @return TDbCommand sql command.
+	 */
+	public function getFindBySqlCommand($conn,$sql,$parameters)
+	{
+		$conn->setActive(true);
+		$command = $conn->createCommand($sql);
+		$this->bindParameterValues($conn,$command,$parameters);
+		return $command;
+	}
+
+	/**
+	 * SQL database command for insert a new record.
+	 * @param TDbConnection database connection.
+	 * @param TActiveRecord new record to be inserted.
+	 * @return TDbCommand active record insert command
+	 */
+	public function getInsertCommand($conn, $record)
+	{
+		$columns = $this->getInsertableColumns($record);
+		$fields = $this->getInsertColumNames($columns);
+		$inserts = $this->getInsertColumnValues($columns);
+		$table = $this->getTableName();
+		$sql = "INSERT INTO {$table} ({$fields}) VALUES ({$inserts})";
+		return $this->createBindedCommand($conn, $sql, array_keys($columns), $columns);
+	}
+
+	/**
+	 * Update the record object's sequence values after insert.
+	 * @param TDbConnection database connection.
+	 * @param TActiveRecord record object.
+	 */
+	public function updatePostInsert($conn, $record)
+	{
+		foreach($this->getColumns() as $name => $column)
+		{
+			if($column->hasSequence())
+				$record->{$name} = $conn->getLastInsertID($column->getSequenceName());
+		}
+	}
+
+	/**
+	 * SQL database command to update an active record.
+	 * @param TDbConnection database connection.
+	 * @param TActiveRecord record for update.
+	 * @return TDbCommand update command.
+	 */
+	public function getUpdateCommand($conn,$record)
+	{
+		$primaryKeys = $this->getPrimaryKeyCriteria();
+		$columns = $this->getUpdatableColumns($record);
+		$updates = $this->getUpdateBindings($columns);
+		$table = $this->getTableName();
+		$sql = "UPDATE {$table} SET {$updates} WHERE {$primaryKeys}";
+		$primaryKeyValues = $this->getObjectKeyValues($this->getPrimaryKeys(), $record);
+		$values = array_merge($columns, $primaryKeyValues);
+		return $this->createBindedCommand($conn, $sql, array_keys($values), $values);
+	}
+
+	/**
+	 * SQL database command to delete an active record.
+	 * @param TDbConnection database connection.
+	 * @param TActiveRecord record for deletion.
+	 * @return TDbCommand delete command.
+	 */
+	public function getDeleteCommand($conn,$record)
+	{
+		$primaryKeys = $this->getPrimaryKeyCriteria();
+		$table = $this->getTableName();
+		$sql = "DELETE FROM {$table} WHERE {$primaryKeys}";
+		$keys = $this->getPrimaryKeys();
+		$values = $this->getObjectKeyValues($keys, $record);
+		return $this->createBindedCommand($conn,$sql, $keys, $values);
+	}
+
+	/**
+	 * SQL command to delete records by primary keys.
+	 * @param TDbConnection database connection.
+	 * @param array list of primary keys
+	 * @return TDbCommand delete command.
+	 */
+	public function getDeleteByPkCommand($conn,$keys)
+	{
+		$conn->setActive(true);
+		$numKeys = count($this->getPrimaryKeys());
+		if($numKeys===0)
+			throw new TActiveRecordException('ar_no_primary_key_found',$this->getTableName());
+		$table = $this->getTableName();
+		if($numKeys===1)
+			$criteria = $this->getDeleteInPkCriteria($conn,$keys);
+		else
+			$criteria = $this->getDeleteMultiplePkCriteria($conn,$keys);
+		$sql = "DELETE FROM {$table} WHERE {$criteria}";
+		$command = $conn->createCommand($sql);
+		$command->prepare();
+		return $command;
+	}
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/Vendor/TDbMetaDataInspector.php b/framework/Data/ActiveRecord/Vendor/TDbMetaDataInspector.php
new file mode 100644
index 00000000..ee7f339e
--- /dev/null
+++ b/framework/Data/ActiveRecord/Vendor/TDbMetaDataInspector.php
@@ -0,0 +1,79 @@
+<?php
+/**
+ * TDbMetaDataInspector class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ */
+
+/**
+ * Base class for database meta data inspectors.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ * @since 3.1
+ */
+abstract class TDbMetaDataInspector
+{
+	private $_connection;
+
+	public function __construct($conn)
+	{
+		$this->setDbConnection($conn);
+	}
+
+	/**
+	 * @param TDbConnection database connection.
+	 */
+	public function setDbConnection($conn)
+	{
+		$this->_connection=$conn;
+	}
+
+	/**
+	 * @return TDbConnection database connection.
+	 */
+	public function getDbConnection()
+	{
+		return $this->_connection;
+	}
+
+	/**
+	 * @param string table name
+	 * @return TDbMetaData table meta data.
+	 */
+	public function getTableMetaData($table)
+	{
+		$keys = $this->getConstraintKeys($table);
+		$columns = $this->getColumnDefinitions($table);
+		return $this->createMetaData($table,$columns,$keys['primary'], $keys['foreign']);
+	}
+
+	/**
+	 * Get the column definitions for given table.
+	 * @param string table name.
+	 * @return array column name value pairs of column meta data.
+	 */
+	abstract protected function getColumnDefinitions($table);
+
+	/**
+	 * Gets the primary and foreign key details for the given table.
+	 * @param string table name.
+	 * @return array key value pairs with keys 'primary' and 'foreign'.
+	 */
+	abstract protected function getConstraintKeys($table);
+
+	/**
+	 * Create a new instance of meta data.
+	 * @param string table name
+	 * @param array column meta data
+	 * @param array primary key meta data
+	 * @param array foreign key meta data.
+	 * @return TDbMetaData table meta data.
+	 */
+	abstract protected function createMetaData($table, $columns, $primary, $foreign);
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/Vendor/TMysqlColumnMetaData.php b/framework/Data/ActiveRecord/Vendor/TMysqlColumnMetaData.php
new file mode 100644
index 00000000..8f4abf99
--- /dev/null
+++ b/framework/Data/ActiveRecord/Vendor/TMysqlColumnMetaData.php
@@ -0,0 +1,105 @@
+<?php
+/**
+ * TMysqlColumnMetaData class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ */
+
+/**
+ * Column meta data for Mysql database.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ * @since 3.1
+ */
+class TMysqlColumnMetaData extends TComponent
+{
+	private $_name;
+	private $_type;
+	private $_autoIncrement;
+	private $_default;
+	private $_notNull=true;
+
+	private $_isPrimary=null;
+
+	/**
+	 * Initialize column meta data.
+	 *
+	 * @param string column name.
+	 * @param string column data type.
+	 * @param string column data length.
+	 * @param boolean column can not be null.
+	 * @param string serial name.
+	 * @param string default value.
+	 */
+	public function __construct($name,$type,$notNull,$autoIncrement,$default,$primary)
+	{
+		$this->_name=$name;
+		$this->_type=$type;
+		$this->_notNull=$notNull;
+		$this->_autoIncrement=$autoIncrement;
+		$this->_default=$default;
+		$this->_isPrimary=$primary;
+	}
+
+	/**
+	 * @return string quoted column name.
+	 */
+	public function getName()
+	{
+		return $this->_name;
+	}
+
+	/**
+	 * @return boolean true if column is a sequence, false otherwise.
+	 */
+	public function hasSequence()
+	{
+		return $this->_autoIncrement;
+	}
+
+	/**
+	 * @return null no sequence name.
+	 */
+	public function getSequenceName()
+	{
+		return null;
+	}
+
+	/**
+	 * @return boolean true if the column is a primary key, or part of a composite primary key.
+	 */
+	public function getIsPrimaryKey()
+	{
+		return $this->_isPrimary;
+	}
+
+	public function getType()
+	{
+		return $this->_type;
+	}
+
+
+	public function getNotNull()
+	{
+		return $this->_notNull;
+	}
+
+	/**
+	 * @return boolean true if column has default value, false otherwise.
+	 */
+	public function hasDefault()
+	{
+		return $this->_default !== null;
+	}
+
+	public function getDefaultValue()
+	{
+		return $this->_default;
+	}
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/Vendor/TMysqlMetaData.php b/framework/Data/ActiveRecord/Vendor/TMysqlMetaData.php
new file mode 100644
index 00000000..7902146d
--- /dev/null
+++ b/framework/Data/ActiveRecord/Vendor/TMysqlMetaData.php
@@ -0,0 +1,47 @@
+<?php
+/**
+ * TMysqlMetaData class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ */
+
+Prado::using('System.Data.ActiveRecord.Vendor.TDbMetaDataCommon');
+
+/**
+ * TMysqlMetaData specialized command builder for Mysql database.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ * @since 3.1
+ */
+class TMysqlMetaData extends TDbMetaDataCommon
+{
+	/**
+	 * Build the SQL search string from the criteria object for Postgress database.
+	 * @param TActiveRecordCriteria search criteria.
+	 * @return string SQL search.
+	 */
+	protected function getSqlFromCriteria(TActiveRecordCriteria $criteria)
+	{
+		$sql = '';
+		if(($condition = $criteria->getCondition())!==null)
+			$sql .= $condition;
+		$orders=array();
+		foreach($criteria->getOrdersBy() as $by=>$ordering)
+			$orders[] = $by.' '.$ordering;
+		if(count($orders) > 0)
+			$sql .= ' ORDER BY '.implode(', ', $orders);
+		if(($limit = $criteria->getLimit())!==null)
+		{
+			$offset = $criteria->getOffset();
+			$offset = $offset===null?0:$offset;
+			$sql .= ' LIMIT '.$offset.', '.$limit;
+		}
+		return strlen($sql) > 0 ? ' WHERE '.$sql : '';
+	}
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/Vendor/TMysqlMetaDataInspector.php b/framework/Data/ActiveRecord/Vendor/TMysqlMetaDataInspector.php
new file mode 100644
index 00000000..6075d2bc
--- /dev/null
+++ b/framework/Data/ActiveRecord/Vendor/TMysqlMetaDataInspector.php
@@ -0,0 +1,80 @@
+<?php
+/**
+ * TMysqlMetaDataInspector class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ */
+
+Prado::using('System.Data.ActiveRecord.Vendor.TDbMetaDataInspector');
+Prado::using('System.Data.ActiveRecord.Vendor.TMysqlColumnMetaData');
+Prado::using('System.Data.ActiveRecord.Vendor.TMysqlMetaData');
+
+/**
+ * TMysqlMetaDataInspector class.
+ *
+ * Gathers table column properties for Mysql database.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ * @since 3.1
+ */
+class TMysqlMetaDataInspector extends TDbMetaDataInspector
+{
+	/**
+	 * Get the column definitions for given table.
+	 * @param string table name.
+	 * @return array column name value pairs of column meta data.
+	 */
+	protected function getColumnDefinitions($table)
+	{
+		$sql="SHOW FULL FIELDS FROM `{$table}`";
+		$conn = $this->getDbConnection();
+		$conn->setActive(true);
+		$command = $conn->createCommand($sql);
+		$command->prepare();
+		foreach($command->query() as $col)
+			$cols[$col['Field']] = $this->getColumnMetaData($col);
+		return $cols;
+	}
+
+	protected function getColumnMetaData($col)
+	{
+		$name = '`'.$col['Field'].'`'; //quote the column names!
+		$type = $col['Type'];
+		$notNull = $col['Null']==='NO';
+		$autoIncrement=is_int(strpos(strtolower($col['Extra']), 'auto_increment'));
+		$default = $col['Default'];
+		$primaryKey = $col['Key']==='PRI';
+		return new TMysqlColumnMetaData($name,$type,$notNull,$autoIncrement,$default,$primaryKey);
+	}
+
+	/**
+	 * Not implemented, Mysql does not always have foreign key constraints.
+	 */
+	protected function getConstraintKeys($table)
+	{
+		return array('primary'=>array(), 'foreign'=>array());
+	}
+
+	/**
+	 * Create a new instance of meta data.
+	 * @param string table name
+	 * @param array column meta data
+	 * @param array primary key meta data
+	 * @param array foreign key meta data.
+	 * @return TDbMetaData table meta data.
+	 */
+	protected function createMetaData($table, $columns, $primary, $foreign)
+	{
+		$pks = array();
+		foreach($columns as $name=>$column)
+			if($column->getIsPrimaryKey())
+				$pks[] = $name;
+		return new TMysqlMetaData($table,$columns,$pks);
+	}
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/Vendor/TPgsqlColumnMetaData.php b/framework/Data/ActiveRecord/Vendor/TPgsqlColumnMetaData.php
new file mode 100644
index 00000000..2b801b09
--- /dev/null
+++ b/framework/Data/ActiveRecord/Vendor/TPgsqlColumnMetaData.php
@@ -0,0 +1,121 @@
+<?php
+/**
+ * TPgsqlColumnMetaData class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ */
+
+/**
+ * Column meta data for Postgre 7.3 or later.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ * @since 3.1
+ */
+class TPgsqlColumnMetaData extends TComponent
+{
+	private $_name;
+	private $_type;
+	private $_sequenceName;
+	private $_default;
+	private $_length;
+	private $_notNull=true;
+
+	private $_isPrimary=null;
+
+	/**
+	 * Initialize column meta data.
+	 *
+	 * @param string column name.
+	 * @param string column data type.
+	 * @param string column data length.
+	 * @param boolean column can not be null.
+	 * @param string serial name.
+	 * @param string default value.
+	 */
+	public function __construct($name,$type,$length,$notNull,$serial,$default)
+	{
+		$this->_name=$name;
+		$this->_type=$type;
+		$this->_length=$length;
+		$this->_notNull=$notNull;
+		$this->_sequenceName=$serial;
+		$this->_default=$default;
+	}
+
+	/**
+	 * @return string quoted column name.
+	 */
+	public function getName()
+	{
+		return $this->_name;
+	}
+
+	/**
+	 * @return boolean true if column is a sequence, false otherwise.
+	 */
+	public function hasSequence()
+	{
+		return $this->_sequenceName != null;
+	}
+
+	/**
+	 * @return string sequence name, only applicable if column is a sequence.
+	 */
+	public function getSequenceName()
+	{
+		return $this->_sequenceName;
+	}
+
+	/**
+	 * Set the column as primary key
+	 */
+	public function setIsPrimaryKey($value)
+	{
+		if($this->_isPrimary===null)
+			$this->_isPrimary=$value;
+		else
+			throw new TActiveRecordException('ar_column_meta_data_read_only');
+	}
+
+	/**
+	 * @return boolean true if the column is a primary key, or part of a composite primary key.
+	 */
+	public function getIsPrimaryKey()
+	{
+		return $this->_isPrimary===null? false : $this->_isPrimary;
+	}
+
+	public function getType()
+	{
+		return $this->_type;
+	}
+
+	public function getLength()
+	{
+		return $this->_length;
+	}
+
+	public function getNotNull()
+	{
+		return $this->_notNull;
+	}
+
+	/**
+	 * @return boolean true if column has default value, false otherwise.
+	 */
+	public function hasDefault()
+	{
+		return $this->_default !== null;
+	}
+
+	public function getDefaultValue()
+	{
+		return $this->_default;
+	}
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/Vendor/TPgsqlMetaData.php b/framework/Data/ActiveRecord/Vendor/TPgsqlMetaData.php
new file mode 100644
index 00000000..7f4f1f82
--- /dev/null
+++ b/framework/Data/ActiveRecord/Vendor/TPgsqlMetaData.php
@@ -0,0 +1,46 @@
+<?php
+/**
+ * TPgsqlMetaData class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ */
+
+Prado::using('System.Data.ActiveRecord.Vendor.TDbMetaDataCommon');
+
+/**
+ * TPgsqlMetaData class.
+ *
+ * Command builder for Postgres database
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ * @since 3.1
+ */
+class TPgsqlMetaData extends TDbMetaDataCommon
+{
+	/**
+	 * Build the SQL search string from the criteria object for Postgress database.
+	 * @param TActiveRecordCriteria search criteria.
+	 * @return string SQL search.
+	 */
+	protected function getSqlFromCriteria(TActiveRecordCriteria $criteria)
+	{
+		$sql = '';
+		if(($condition = $criteria->getCondition())!==null)
+			$sql .= $condition;
+		$orders=array();
+		foreach($criteria->getOrdersBy() as $by=>$ordering)
+			$orders[] = $by.' '.$ordering;
+		if(count($orders) > 0)
+			$sql .= ' ORDER BY '.implode(', ', $orders);
+		if(($limit = $criteria->getLimit())!==null)
+			$sql .= ' LIMIT '.$limit;
+		if(($offset = $criteria->getOffset())!==null)
+			$sql .= ' OFFSET '.$offset;
+		return strlen($sql) > 0 ? ' WHERE '.$sql : '';
+	}
+}
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/Vendor/TPgsqlMetaDataInspector.php b/framework/Data/ActiveRecord/Vendor/TPgsqlMetaDataInspector.php
new file mode 100644
index 00000000..df31b9c0
--- /dev/null
+++ b/framework/Data/ActiveRecord/Vendor/TPgsqlMetaDataInspector.php
@@ -0,0 +1,223 @@
+<?php
+/**
+ * TPgsqlMetaDataInspector class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ */
+
+Prado::using('System.Data.ActiveRecord.Vendor.TDbMetaDataInspector');
+Prado::using('System.Data.ActiveRecord.Vendor.TPgsqlColumnMetaData');
+Prado::using('System.Data.ActiveRecord.Vendor.TPgsqlMetaData');
+
+/**
+ * Table meta data inspector for Postgres database 7.3 or later.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ * @since 3.1
+ */
+class TPgsqlMetaDataInspector extends TDbMetaDataInspector
+{
+	private $_schema = 'public';
+
+	/**
+	 * @param string default schema.
+	 */
+	public function setDefaultSchema($schema)
+	{
+		$this->_schema=$schema;
+	}
+
+	/**
+	 * @return string default schema.
+	 */
+	public function getDefaultSchema()
+	{
+		return $this->_schema;
+	}
+
+	/**
+	 * Create a new instance of meta data.
+	 * @param string table name
+	 * @param array column meta data
+	 * @param array primary key meta data
+	 * @param array foreign key meta data.
+	 * @return TDbMetaData table meta data.
+	 */
+	protected function createMetaData($table, $columns, $primary, $foreign)
+	{
+		foreach($primary as $column)
+			$columns[$column]->setIsPrimaryKey(true);
+		return new TPgsqlMetaData($table,$columns,$primary,$foreign,$this->getIsView($table));
+	}
+
+	protected function getIsView($table)
+	{
+		$sql =
+<<<EOD
+		SELECT count(c.relname) FROM pg_catalog.pg_class c
+		LEFT JOIN pg_catalog.pg_namespace n ON (n.oid = c.relnamespace)
+		WHERE (n.nspname=:schema) AND (c.relkind = 'v'::"char") AND c.relname = :table
+EOD;
+		$conn=$this->getDbConnection();
+		$conn->setActive(true);
+		$command=$conn->createCommand($sql);
+		$command->bindValue(':schema',$this->getDefaultSchema());
+		$command->bindValue(':table', $table);
+		return intval($command->queryScalar()) === 1;
+	}
+
+	/**
+	 * Get the column definitions for given table.
+	 * @param string table name.
+	 * @return array column name value pairs of column meta data.
+	 */
+	protected function getColumnDefinitions($table)
+	{
+		// This query is made much more complex by the addition of the 'attisserial' field.
+		// The subquery to get that field checks to see if there is an internally dependent
+		// sequence on the field.
+		$sql =
+<<<EOD
+		SELECT
+			a.attname,
+			pg_catalog.format_type(a.atttypid, a.atttypmod) as type,
+			a.atttypmod,
+			a.attnotnull, a.atthasdef, adef.adsrc,
+			(
+				SELECT 1 FROM pg_catalog.pg_depend pd, pg_catalog.pg_class pc
+				WHERE pd.objid=pc.oid
+				AND pd.classid=pc.tableoid
+				AND pd.refclassid=pc.tableoid
+				AND pd.refobjid=a.attrelid
+				AND pd.refobjsubid=a.attnum
+				AND pd.deptype='i'
+				AND pc.relkind='S'
+			) IS NOT NULL AS attisserial
+
+		FROM
+			pg_catalog.pg_attribute a LEFT JOIN pg_catalog.pg_attrdef adef
+			ON a.attrelid=adef.adrelid
+			AND a.attnum=adef.adnum
+			LEFT JOIN pg_catalog.pg_type t ON a.atttypid=t.oid
+		WHERE
+			a.attrelid = (SELECT oid FROM pg_catalog.pg_class WHERE relname=:table
+				AND relnamespace = (SELECT oid FROM pg_catalog.pg_namespace WHERE
+				nspname = :schema))
+			AND a.attnum > 0 AND NOT a.attisdropped
+		ORDER BY a.attnum
+EOD;
+		$conn = $this->getDbConnection();
+		$conn->setActive(true);
+		$command = $conn->createCommand($sql);
+		$command->bindValue(':table', $table);
+		$command->bindValue(':schema', $this->getDefaultSchema());
+		$cols = array();
+		foreach($command->query() as $col)
+			$cols[$col['attname']] = $this->getColumnMetaData($col);
+		return $cols;
+	}
+
+	/**
+	 * Returns the column details.
+	 * @param array column details.
+	 * @return TPgsqlColumnMetaData column meta data.
+	 */
+	protected function getColumnMetaData($col)
+	{
+		$name = '"'.$col['attname'].'"'; //quote the column names!
+		$type = $col['type'];
+
+		// A specific constant in the 7.0 source, the length is offset by 4.
+		$length = $col['atttypmod'] > 0 ? $col['atttypmod'] - 4 : -1;
+		$notNull = $col['attnotnull'];
+		$serial = $col['attisserial'] ? $this->getSerialName($col['adsrc']) : null;
+		$default = $serial === null && $col['atthasdef'] ? $col['adsrc'] : null;
+		return new TPgsqlColumnMetaData($name,$type,$length,$notNull,$serial,$default);
+	}
+
+	/**
+	 * @return string serial name if found, null otherwise.
+	 */
+	protected function getSerialName($src)
+	{
+		$matches = array();
+		if(preg_match('/nextval\(\'([^\']+)\'::regclass\)/i',$src,$matches))
+			return $matches[1];
+	}
+
+	/**
+	 * Gets the primary and foreign key details for the given table.
+	 * @param string table name.
+	 * @return array key value pairs with keys 'primary' and 'foreign'.
+	 */
+	protected function getConstraintKeys($table)
+	{
+		$sql = 'SELECT
+				pg_catalog.pg_get_constraintdef(pc.oid, true) AS consrc,
+				pc.contype
+			FROM
+				pg_catalog.pg_constraint pc
+			WHERE
+				pc.conrelid = (SELECT oid FROM pg_catalog.pg_class WHERE relname=:table
+					AND relnamespace = (SELECT oid FROM pg_catalog.pg_namespace
+					WHERE nspname=:schema))
+		';
+		$this->getDbConnection()->setActive(true);
+		$command = $this->getDbConnection()->createCommand($sql);
+		$command->bindValue(':table', $table);
+		$command->bindValue(':schema', $this->getDefaultSchema());
+		$keys['primary'] = array();
+		$keys['foreign'] = array();
+		foreach($command->query() as $row)
+		{
+			if($row['contype']==='p')
+				$keys['primary'] = $this->getPrimaryKeys($row['consrc']);
+			else if($row['contype'] === 'f')
+			{
+				$fkey = $this->getForeignKeys($row['consrc']);
+				if($fkey!==null)
+					$keys['foreign'][] = $fkey;
+			}
+		}
+		return $keys;
+	}
+
+	/**
+	 * Gets the primary key field names
+	 * @param string pgsql primary key definition
+	 * @return array primary key field names.
+	 */
+	protected function getPrimaryKeys($src)
+	{
+		$matches = array();
+		if(preg_match('/PRIMARY\s+KEY\s+\(([^\)]+)\)/i', $src, $matches))
+			return preg_split('/,\s+/',$matches[1]);
+		return array();
+	}
+
+	/**
+	 * Gets foreign relationship constraint keys and table name
+	 * @param string pgsql foreign key definition
+	 * @return array foreign relationship table name and keys, null otherwise
+	 */
+	protected function getForeignKeys($src)
+	{
+		$matches = array();
+		$brackets = '\(([^\)]+)\)';
+		$find = "/FOREIGN\s+KEY\s+{$brackets}\s+REFERENCES\s+([^\(]+){$brackets}/i";
+		if(preg_match($find, $src, $matches))
+		{
+			$keys = preg_split('/,\s+/', $matches[1]);
+			$fkeys = array();
+			foreach(preg_split('/,\s+/', $matches[3]) as $i => $fkey)
+				$fkeys[$keys[$i]] = $fkey;
+			return array('table' => $matches[2], 'keys' => $fkeys);
+		}
+	}
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/Vendor/TSqliteColumnMetaData.php b/framework/Data/ActiveRecord/Vendor/TSqliteColumnMetaData.php
new file mode 100644
index 00000000..94029cfa
--- /dev/null
+++ b/framework/Data/ActiveRecord/Vendor/TSqliteColumnMetaData.php
@@ -0,0 +1,96 @@
+<?php
+/**
+ * TSqliteColumnMetaData class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ */
+
+/**
+ * TSqliteColumnMetaData class.
+ *
+ * Column details for SQLite version 2.x or 3.x. database.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ * @since 3.1
+ */
+class TSqliteColumnMetaData extends TComponent
+{
+	private $_name;
+	private $_type;
+	private $_notNull;
+	private $_autoIncrement;
+	private $_default;
+	private $_primary=false;
+
+	public function __construct($name,$type,$notNull,$autoIncrement,$default,$primary)
+	{
+		$this->_name=$name;
+		$this->_type=$type;
+		$this->_notNull=$notNull;
+		$this->_autoIncrement=$autoIncrement;
+		$this->_default=$default;
+		$this->_primary=$primary;
+	}
+
+	/**
+	 * @return string quoted column name.
+	 */
+	public function getName()
+	{
+		return $this->_name;
+	}
+
+	/**
+	 * @return boolean true if column is a sequence, false otherwise.
+	 */
+	public function hasSequence()
+	{
+		return $this->_autoIncrement;
+	}
+
+	/**
+	 * @return null no sequence name.
+	 */
+	public function getSequenceName()
+	{
+		return null;
+	}
+
+	/**
+	 * @return boolean true if the column is a primary key, or part of a composite primary key.
+	 */
+	public function getIsPrimaryKey()
+	{
+		return $this->_primary;
+	}
+
+	public function getType()
+	{
+		return $this->_type;
+	}
+
+
+	public function getNotNull()
+	{
+		return $this->_notNull;
+	}
+
+	/**
+	 * @return boolean true if column has default value, false otherwise.
+	 */
+	public function hasDefault()
+	{
+		return $this->_default !== null;
+	}
+
+	public function getDefaultValue()
+	{
+		return $this->_default;
+	}
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/Vendor/TSqliteMetaData.php b/framework/Data/ActiveRecord/Vendor/TSqliteMetaData.php
new file mode 100644
index 00000000..a5f45090
--- /dev/null
+++ b/framework/Data/ActiveRecord/Vendor/TSqliteMetaData.php
@@ -0,0 +1,73 @@
+<?php
+/**
+ * TSqliteMetaData class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ */
+
+Prado::using('System.Data.ActiveRecord.Vendor.TDbMetaDataCommon');
+
+/**
+ * TSqliteMetaData specialized command builder for SQLite database.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ * @since 3.1
+ */
+class TSqliteMetaData extends TDbMetaDataCommon
+{
+	/**
+	 * Build the SQL search string from the criteria object for Postgress database.
+	 * @param TActiveRecordCriteria search criteria.
+	 * @return string SQL search.
+	 */
+	protected function getSqlFromCriteria(TActiveRecordCriteria $criteria)
+	{
+		$sql = '';
+		if(($condition = $criteria->getCondition())!==null)
+			$sql .= $condition;
+		$orders=array();
+		foreach($criteria->getOrdersBy() as $by=>$ordering)
+			$orders[] = $by.' '.$ordering;
+		if(count($orders) > 0)
+			$sql .= ' ORDER BY '.implode(', ', $orders);
+		if(($limit = $criteria->getLimit())!==null)
+		{
+			$offset = $criteria->getOffset();
+			$offset = $offset===null?0:$offset;
+			$sql .= ' LIMIT '.$offset.', '.$limit;
+		}
+		return strlen($sql) > 0 ? ' WHERE '.$sql : '';
+	}
+
+	/**
+	 * Remove quote from the keys in the data.
+	 * @param mixed record row
+	 * @return array record row
+	 */
+	public function postQueryRow($row)
+	{
+		if(!is_array($row)) return $row;
+		$result=array();
+		foreach($row as $k=>$v)
+			$result[str_replace('"','',$k)]=$v;
+		return $result;
+	}
+
+	/**
+	 * Remove quote from the keys in the data.
+	 * @param mixed record row
+	 * @return array record row
+	 */
+	public function postQuery($rows)
+	{
+		foreach($rows as $k=>$v)
+			$rows[$k] = $this->postQueryRow($v);
+		return $rows;
+	}
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/ActiveRecord/Vendor/TSqliteMetaDataInspector.php b/framework/Data/ActiveRecord/Vendor/TSqliteMetaDataInspector.php
new file mode 100644
index 00000000..07fa3187
--- /dev/null
+++ b/framework/Data/ActiveRecord/Vendor/TSqliteMetaDataInspector.php
@@ -0,0 +1,85 @@
+<?php
+/**
+ * TSqliteMetaDataInspector class file.
+ *
+ * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ */
+
+Prado::using('System.Data.ActiveRecord.Vendor.TDbMetaDataInspector');
+Prado::using('System.Data.ActiveRecord.Vendor.TSqliteColumnMetaData');
+Prado::using('System.Data.ActiveRecord.Vendor.TSqliteMetaData');
+
+/**
+ * Table meta data inspector for Sqlite database.
+ *
+ * @author Wei Zhuo <weizho[at]gmail[dot]com>
+ * @version $Id$
+ * @package System.Data.ActiveRecord.Vendor
+ * @since 3.1
+ */
+class TSqliteMetaDataInspector extends TDbMetaDataInspector
+{
+	/**
+	 * Create a new instance of meta data.
+	 * @param string table name
+	 * @param array column meta data
+	 * @param array primary key meta data
+	 * @param array foreign key meta data.
+	 * @return TDbMetaData table meta data.
+	 */
+	protected function createMetaData($table, $columns, $primary, $foreign)
+	{
+		$pks = array();
+		foreach($columns as $name=>$column)
+			if($column->getIsPrimaryKey())
+				$pks[] = $name;
+		return new TSqliteMetaData($table,$columns,$pks);
+	}
+
+	/**
+	 * Get the column definitions for given table.
+	 * @param string table name.
+	 * @return array column name value pairs of column meta data.
+	 */
+	protected function getColumnDefinitions($table)
+	{
+		$conn=$this->getDbConnection();
+		$conn->setActive(true);
+		$table = $conn->quoteString($table);
+		$command = $conn->createCommand("PRAGMA table_info({$table})");
+		$command->prepare();
+		$cols = array();
+		foreach($command->query() as $col)
+			$cols[$col['name']] = $this->getColumnMetaData($col);
+		return $cols;
+	}
+
+	/**
+	 * Returns the column details.
+	 * @param array column details.
+	 * @return TPgsqlColumnMetaData column meta data.
+	 */
+	protected function getColumnMetaData($col)
+	{
+		$name = '"'.$col['name'].'"'; //quote the column names!
+		$type = $col['type'];
+
+		$notNull = $col['notnull']==='99';
+		$primary = $col['pk']==='1';
+		$autoIncrement = strtolower($type)==='integer' && $primary;
+		$default = $col['dflt_value'];
+		return new TSqliteColumnMetaData($name,$type,$notNull,$autoIncrement,$default,$primary);
+	}
+
+	/**
+	 * Not implemented, sqlite does not have foreign key constraints.
+	 */
+	protected function getConstraintKeys($table)
+	{
+		return array('primary'=>array(), 'foreign'=>array());
+	}
+}
+
+?>
+\ No newline at end of file
diff --git a/framework/Data/TDbCommand.php b/framework/Data/TDbCommand.php
index 91b165fa..82e46a25 100644
--- a/framework/Data/TDbCommand.php
+++ b/framework/Data/TDbCommand.php
@@ -155,9 +155,9 @@ class TDbCommand extends TComponent
 	{
 		$this->prepare();
 		if($dataType===null)
-			$this->_statement->bindParam($name,$value);
+			$this->_statement->bindValue($name,$value);
 		else
-			$this->_statement->bindParam($name,$value,$dataType);
+			$this->_statement->bindValue($name,$value,$dataType);
 	}
 
 	/**
@@ -177,7 +177,11 @@ class TDbCommand extends TComponent
 				return $this->_statement->rowCount();
 			}
 			else
-				return $this->getConnection()->getPdoInstance()->exec($this->getText());
+			{
+				$int = $this->getConnection()->getPdoInstance()->exec($this->getText());
+				var_dump($int);
+				return $int;
+			}
 		}
 		catch(Exception $e)
 		{