diff --git a/framework/db/Exception.php b/framework/db/Exception.php
index 242361f..17c5965 100644
--- a/framework/db/Exception.php
+++ b/framework/db/Exception.php
@@ -1,22 +1,22 @@
 <?php
 /**
- * CDbException class file.
+ * Exception class file.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\db;
+
 /**
  * CDbException represents an exception that is caused by some DB-related operations.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id: CDbException.php 2799 2011-01-01 19:31:13Z qiang.xue $
- * @package system.db
- * @since 1.0
+ * @since 2.0
  */
-class CDbException extends CException
+class Exception extends \yii\base\Exception
 {
 	/**
 	 * @var mixed the error info provided by a PDO exception. This is the same as returned
diff --git a/framework/db/dao/Command.php b/framework/db/dao/Command.php
index f1efef1..5df6965 100644
--- a/framework/db/dao/Command.php
+++ b/framework/db/dao/Command.php
@@ -10,6 +10,8 @@
 
 namespace yii\db\dao;
 
+use yii\db\Exception;
+
 /**
  * Command represents a SQL statement to be executed against a database.
  *
diff --git a/framework/db/dao/Connection.php b/framework/db/dao/Connection.php
index 2d4b8a7..b3e6965 100644
--- a/framework/db/dao/Connection.php
+++ b/framework/db/dao/Connection.php
@@ -10,6 +10,8 @@
 
 namespace yii\db\dao;
 
+use yii\db\Exception;
+
 /**
  * Connection represents a connection to a database via [PDO](http://www.php.net/manual/en/ref.pdo.php).
  *
@@ -275,7 +277,7 @@ class Connection extends \yii\base\ApplicationComponent
 	 */
 	public static function getAvailableDrivers()
 	{
-		return PDO::getAvailableDrivers();
+		return \PDO::getAvailableDrivers();
 	}
 
 	/**
@@ -485,7 +487,7 @@ class Connection extends \yii\base\ApplicationComponent
 	 */
 	public function quoteValue($str)
 	{
-		if (is_int($str) || is_float($str) || is_bool($str)) {
+		if (!is_string($str)) {
 			return $str;
 		}
 
@@ -504,9 +506,9 @@ class Connection extends \yii\base\ApplicationComponent
 	 * @param string $name table name
 	 * @return string the properly quoted table name
 	 */
-	public function quoteTableName($name)
+	public function quoteTableName($name, $simple = false)
 	{
-		return $this->getSchema()->quoteTableName($name);
+		return $simple ? $this->getSchema()->quoteSimpleTableName($name) : $this->getSchema()->quoteTableName($name);
 	}
 
 	/**
@@ -515,9 +517,9 @@ class Connection extends \yii\base\ApplicationComponent
 	 * @param string $name column name
 	 * @return string the properly quoted column name
 	 */
-	public function quoteColumnName($name)
+	public function quoteColumnName($name, $simple = false)
 	{
-		return $this->getSchema()->quoteColumnName($name);
+		return $simple ? $this->getSchema()->quoteColumnName($name) : $this->getSchema()->quoteSimpleColumnName($name);
 	}
 
 	/**
@@ -528,13 +530,13 @@ class Connection extends \yii\base\ApplicationComponent
 	 */
 	public function getPdoType($type)
 	{
-		static $map = array(
+		static $typeMap = array(
 			'boolean' => \PDO::PARAM_BOOL,
 			'integer' => \PDO::PARAM_INT,
 			'string' => \PDO::PARAM_STR,
 			'NULL' => \PDO::PARAM_NULL,
 		);
-		return isset($map[$type]) ? $map[$type] : PDO::PARAM_STR;
+		return isset($typeMap[$type]) ? $typeMap[$type] : \PDO::PARAM_STR;
 	}
 
 	/**
@@ -547,7 +549,7 @@ class Connection extends \yii\base\ApplicationComponent
 			return strtolower(substr($this->dsn, 0, $pos));
 		}
 		else {
-			return $this->getAttribute(\PDO::ATTR_DRIVER_NAME);
+			return strtolower($this->getAttribute(\PDO::ATTR_DRIVER_NAME));
 		}
 	}
 
diff --git a/framework/db/dao/DataReader.php b/framework/db/dao/DataReader.php
index d2228d8..858b74e 100644
--- a/framework/db/dao/DataReader.php
+++ b/framework/db/dao/DataReader.php
@@ -10,6 +10,8 @@
 
 namespace yii\db\dao;
 
+use yii\db\Exception;
+
 /**
  * DataReader represents a forward-only stream of rows from a query result set.
  *
diff --git a/framework/db/dao/QueryBuilder.php b/framework/db/dao/QueryBuilder.php
index fbbc05e..c769828 100644
--- a/framework/db/dao/QueryBuilder.php
+++ b/framework/db/dao/QueryBuilder.php
@@ -10,6 +10,8 @@
 
 namespace yii\db\dao;
 
+use yii\db\Exception;
+
 /**
  * QueryBuilder builds a SQL statement based on the specification given as a [[Query]] object.
  *
diff --git a/framework/db/dao/Schema.php b/framework/db/dao/Schema.php
index a831a31..5632e86 100644
--- a/framework/db/dao/Schema.php
+++ b/framework/db/dao/Schema.php
@@ -10,6 +10,8 @@
 
 namespace yii\db\dao;
 
+use yii\db\Exception;
+
 /**
  * Schema is the base class for retrieving metadata information.
  *
diff --git a/framework/db/dao/Transaction.php b/framework/db/dao/Transaction.php
index b9fd97e..87e4d89 100644
--- a/framework/db/dao/Transaction.php
+++ b/framework/db/dao/Transaction.php
@@ -10,6 +10,8 @@
 
 namespace yii\db\dao;
 
+use yii\db\Exception;
+
 /**
  * Transaction represents a DB transaction.
  *
diff --git a/tests/unit/TestCase.php b/tests/unit/TestCase.php
new file mode 100644
index 0000000..c7826c8
--- /dev/null
+++ b/tests/unit/TestCase.php
@@ -0,0 +1,14 @@
+<?php
+
+class TestCase extends \yii\test\TestCase
+{
+	public $params;
+
+	function getParam($name)
+	{
+		if ($this->params === null) {
+			$this->params = require(__DIR__ . '/data/config.php');
+		}
+		return isset($this->params[$name]) ? $this->params[$name] : null;
+	}
+}
\ No newline at end of file
diff --git a/tests/unit/bootstrap.php b/tests/unit/bootstrap.php
index daba4c9..5a8aeaa 100644
--- a/tests/unit/bootstrap.php
+++ b/tests/unit/bootstrap.php
@@ -7,3 +7,4 @@ $_SERVER['SCRIPT_NAME'] = '/' . __DIR__;
 $_SERVER['SCRIPT_FILENAME'] = __FILE__;
 
 require_once(__DIR__ . '/../../framework/yii.php');
+require_once(__DIR__ . '/TestCase.php');
\ No newline at end of file
diff --git a/tests/unit/data/config.php b/tests/unit/data/config.php
new file mode 100644
index 0000000..865edc6
--- /dev/null
+++ b/tests/unit/data/config.php
@@ -0,0 +1,9 @@
+<?php
+
+return array(
+	'mysql' => array(
+		'dsn' => 'mysql:host=127.0.0.1;dbname=yiitest',
+		'username' => 'root',
+		'password' => '',
+	),
+);
\ No newline at end of file
diff --git a/tests/unit/data/mssql.sql b/tests/unit/data/mssql.sql
new file mode 100644
index 0000000..38967b2
--- /dev/null
+++ b/tests/unit/data/mssql.sql
@@ -0,0 +1,306 @@
+SET ANSI_NULLS ON
+GO
+SET QUOTED_IDENTIFIER ON
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[categories]') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)
+BEGIN
+CREATE TABLE [dbo].[categories](
+	[id] [int] IDENTITY(1,1) NOT NULL,
+	[name] [varchar](128) NOT NULL,
+	[parent_id] [int] NULL,
+ CONSTRAINT [PK_categories] PRIMARY KEY CLUSTERED 
+(
+	[id] ASC
+) ON [PRIMARY]
+) ON [PRIMARY]
+END
+GO
+SET ANSI_NULLS ON
+GO
+SET QUOTED_IDENTIFIER ON
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[orders]') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)
+BEGIN
+CREATE TABLE [dbo].[orders](
+	[key1] [int] NOT NULL,
+	[key2] [int] NOT NULL,
+	[name] [varchar](128) NOT NULL,
+ CONSTRAINT [PK_orders] PRIMARY KEY CLUSTERED 
+(
+	[key1] ASC,
+	[key2] ASC
+) ON [PRIMARY]
+) ON [PRIMARY]
+END
+GO
+SET ANSI_NULLS ON
+GO
+SET QUOTED_IDENTIFIER ON
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[types]') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)
+BEGIN
+CREATE TABLE [dbo].[types](
+	[int_col] [int] NOT NULL,
+	[int_col2] [int] NULL CONSTRAINT [DF_types_int_col2]  DEFAULT (1),
+	[char_col] [char](100) NOT NULL,
+	[char_col2] [varchar](100) NULL CONSTRAINT [DF_types_char_col2]  DEFAULT ('something'),
+	[char_col3] [text] NULL,
+	[float_col] [real] NOT NULL,
+	[float_col2] [float] NULL CONSTRAINT [DF_types_float_col2]  DEFAULT (1.23),
+	[blob_col] [image] NULL,
+	[numeric_col] [numeric](5, 2) NULL CONSTRAINT [DF_types_numeric_col]  DEFAULT (33.22),
+	[time] [datetime] NULL CONSTRAINT [DF_types_time]  DEFAULT ('2002-01-01 00:00:00'),
+	[bool_col] [bit] NOT NULL,
+	[bool_col2] [bit] NOT NULL CONSTRAINT [DF_types_bool_col2]  DEFAULT (1)
+) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
+END
+GO
+SET ANSI_NULLS ON
+GO
+SET QUOTED_IDENTIFIER ON
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[users]') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)
+BEGIN
+CREATE TABLE [dbo].[users](
+	[id] [int] IDENTITY(1,1) NOT NULL,
+	[username] [varchar](128) NOT NULL,
+	[password] [varchar](128) NOT NULL,
+	[email] [varchar](128) NOT NULL,
+ CONSTRAINT [PK_users] PRIMARY KEY CLUSTERED 
+(
+	[id] ASC
+) ON [PRIMARY]
+) ON [PRIMARY]
+END
+GO
+SET ANSI_NULLS ON
+GO
+SET QUOTED_IDENTIFIER ON
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[post_category]') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)
+BEGIN
+CREATE TABLE [dbo].[post_category](
+	[category_id] [int] NOT NULL,
+	[post_id] [int] NOT NULL,
+ CONSTRAINT [PK_post_category] PRIMARY KEY CLUSTERED 
+(
+	[category_id] ASC,
+	[post_id] ASC
+) ON [PRIMARY]
+) ON [PRIMARY]
+END
+GO
+SET ANSI_NULLS ON
+GO
+SET QUOTED_IDENTIFIER ON
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[items]') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)
+BEGIN
+CREATE TABLE [dbo].[items](
+	[id] [int] IDENTITY(1,1) NOT NULL,
+	[name] [varchar](128) NULL,
+	[col1] [int] NOT NULL,
+	[col2] [int] NOT NULL,
+ CONSTRAINT [PK_items] PRIMARY KEY CLUSTERED 
+(
+	[id] ASC
+) ON [PRIMARY]
+) ON [PRIMARY]
+END
+GO
+SET ANSI_NULLS ON
+GO
+SET QUOTED_IDENTIFIER ON
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[comments]') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)
+BEGIN
+CREATE TABLE [dbo].[comments](
+	[id] [int] IDENTITY(1,1) NOT NULL,
+	[content] [text] NOT NULL,
+	[post_id] [int] NOT NULL,
+	[author_id] [int] NOT NULL,
+ CONSTRAINT [PK_comments] PRIMARY KEY CLUSTERED 
+(
+	[id] ASC
+) ON [PRIMARY]
+) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
+END
+GO
+SET ANSI_NULLS ON
+GO
+SET QUOTED_IDENTIFIER ON
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[posts]') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)
+BEGIN
+CREATE TABLE [dbo].[posts](
+	[id] [int] IDENTITY(1,1) NOT NULL,
+	[title] [varchar](128) NOT NULL,
+	[create_time] [datetime] NOT NULL,
+	[author_id] [int] NOT NULL,
+	[content] [text] NULL,
+ CONSTRAINT [PK_posts] PRIMARY KEY CLUSTERED 
+(
+	[id] ASC
+) ON [PRIMARY]
+) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
+END
+GO
+SET ANSI_NULLS ON
+GO
+SET QUOTED_IDENTIFIER ON
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[profiles]') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)
+BEGIN
+CREATE TABLE [dbo].[profiles](
+	[id] [int] IDENTITY(1,1) NOT NULL,
+	[first_name] [varchar](128) NOT NULL,
+	[last_name] [varchar](128) NOT NULL,
+	[user_id] [int] NOT NULL,
+ CONSTRAINT [PK_profiles] PRIMARY KEY CLUSTERED 
+(
+	[id] ASC
+) ON [PRIMARY]
+) ON [PRIMARY]
+END
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[FK_categories_categories]') AND type = 'F')
+ALTER TABLE [dbo].[categories]  WITH CHECK ADD  CONSTRAINT [FK_categories_categories] FOREIGN KEY([parent_id])
+REFERENCES [dbo].[categories] ([id])
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[FK_post_category_categories]') AND type = 'F')
+ALTER TABLE [dbo].[post_category]  WITH CHECK ADD  CONSTRAINT [FK_post_category_categories] FOREIGN KEY([category_id])
+REFERENCES [dbo].[categories] ([id])
+ON DELETE CASCADE
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[FK_post_category_posts]') AND type = 'F')
+ALTER TABLE [dbo].[post_category]  WITH NOCHECK ADD  CONSTRAINT [FK_post_category_posts] FOREIGN KEY([post_id])
+REFERENCES [dbo].[posts] ([id])
+ON DELETE CASCADE
+GO
+ALTER TABLE [dbo].[post_category] CHECK CONSTRAINT [FK_post_category_posts]
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[FK_items_orders]') AND type = 'F')
+ALTER TABLE [dbo].[items]  WITH CHECK ADD  CONSTRAINT [FK_items_orders] FOREIGN KEY([col1], [col2])
+REFERENCES [dbo].[orders] ([key1], [key2])
+ON DELETE CASCADE
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[FK_comments_users]') AND type = 'F')
+ALTER TABLE [dbo].[comments]  WITH NOCHECK ADD  CONSTRAINT [FK_comments_users] FOREIGN KEY([author_id])
+REFERENCES [dbo].[users] ([id])
+ON DELETE CASCADE
+GO
+ALTER TABLE [dbo].[comments] CHECK CONSTRAINT [FK_comments_users]
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[FK_post_comment]') AND type = 'F')
+ALTER TABLE [dbo].[comments]  WITH NOCHECK ADD  CONSTRAINT [FK_post_comment] FOREIGN KEY([post_id])
+REFERENCES [dbo].[posts] ([id])
+ON DELETE CASCADE
+GO
+ALTER TABLE [dbo].[comments] CHECK CONSTRAINT [FK_post_comment]
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[FK_posts_users]') AND type = 'F')
+ALTER TABLE [dbo].[posts]  WITH NOCHECK ADD  CONSTRAINT [FK_posts_users] FOREIGN KEY([author_id])
+REFERENCES [dbo].[users] ([id])
+GO
+ALTER TABLE [dbo].[posts] CHECK CONSTRAINT [FK_posts_users]
+GO
+IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].[FK_profile_user]') AND type = 'F')
+ALTER TABLE [dbo].[profiles]  WITH NOCHECK ADD  CONSTRAINT [FK_profile_user] FOREIGN KEY([user_id])
+REFERENCES [dbo].[users] ([id])
+ON DELETE CASCADE
+GO
+ALTER TABLE [dbo].[profiles] CHECK CONSTRAINT [FK_profile_user]
+
+INSERT INTO users (username, password, email) VALUES ('user1','pass1','email1')
+GO
+INSERT INTO users (username, password, email) VALUES ('user2','pass2','email2')
+GO
+INSERT INTO users (username, password, email) VALUES ('user3','pass3','email3')
+GO
+
+INSERT INTO profiles (first_name, last_name, user_id) VALUES ('first 1','last 1',1)
+GO
+INSERT INTO profiles (first_name, last_name, user_id) VALUES ('first 2','last 2',2)
+GO
+
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 1','2000-01-01',1,'content 1')
+GO
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 2','2000-01-02',2,'content 2')
+GO
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 3','2000-01-03',2,'content 3')
+GO
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 4','2000-01-04',2,'content 4')
+GO
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 5','2000-01-05',3,'content 5')
+GO
+
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 1',1, 2)
+GO
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 2',1, 2)
+GO
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 3',1, 2)
+GO
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 4',2, 2)
+GO
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 5',2, 2)
+GO
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 6',3, 2)
+GO
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 7',3, 2)
+GO
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 8',3, 2)
+GO
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 9',3, 2)
+GO
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 10',5, 3)
+GO
+
+INSERT INTO categories (name, parent_id) VALUES ('cat 1',NULL)
+GO
+INSERT INTO categories (name, parent_id) VALUES ('cat 2',NULL)
+GO
+INSERT INTO categories (name, parent_id) VALUES ('cat 3',NULL)
+GO
+INSERT INTO categories (name, parent_id) VALUES ('cat 4',1)
+GO
+INSERT INTO categories (name, parent_id) VALUES ('cat 5',1)
+GO
+INSERT INTO categories (name, parent_id) VALUES ('cat 6',5)
+GO
+INSERT INTO categories (name, parent_id) VALUES ('cat 7',5)
+GO
+
+INSERT INTO post_category (category_id, post_id) VALUES (1,1)
+GO
+INSERT INTO post_category (category_id, post_id) VALUES (2,1)
+GO
+INSERT INTO post_category (category_id, post_id) VALUES (3,1)
+GO
+INSERT INTO post_category (category_id, post_id) VALUES (4,2)
+GO
+INSERT INTO post_category (category_id, post_id) VALUES (1,2)
+GO
+INSERT INTO post_category (category_id, post_id) VALUES (1,3)
+GO
+
+
+INSERT INTO orders (key1,key2,name) VALUES (1,2,'order 12')
+GO
+INSERT INTO orders (key1,key2,name) VALUES (1,3,'order 13')
+GO
+INSERT INTO orders (key1,key2,name) VALUES (2,1,'order 21')
+GO
+INSERT INTO orders (key1,key2,name) VALUES (2,2,'order 22')
+GO
+
+
+INSERT INTO items (name,col1,col2) VALUES ('item 1',1,2)
+GO
+INSERT INTO items (name,col1,col2) VALUES ('item 2',1,2)
+GO
+INSERT INTO items (name,col1,col2) VALUES ('item 3',1,3)
+GO
+INSERT INTO items (name,col1,col2) VALUES ('item 4',2,2)
+GO
+INSERT INTO items (name,col1,col2) VALUES ('item 5',2,2)
+GO
diff --git a/tests/unit/data/mysql.sql b/tests/unit/data/mysql.sql
new file mode 100644
index 0000000..057b1ad
--- /dev/null
+++ b/tests/unit/data/mysql.sql
@@ -0,0 +1,150 @@
+/**
+ * This is the database schema for testing MySQL support of yii Active Record.
+ * To test this feature, you need to create a database named 'yii' on 'localhost'
+ * and create an account 'test/test' which owns this test database.
+ */
+
+CREATE TABLE users
+(
+	id INTEGER NOT NULL PRIMARY KEY AUTO_INCREMENT,
+	username VARCHAR(128) NOT NULL,
+	password VARCHAR(128) NOT NULL,
+	email VARCHAR(128) NOT NULL
+) TYPE=INNODB;
+
+INSERT INTO users (username, password, email) VALUES ('user1','pass1','email1');
+INSERT INTO users (username, password, email) VALUES ('user2','pass2','email2');
+INSERT INTO users (username, password, email) VALUES ('user3','pass3','email3');
+
+CREATE TABLE profiles
+(
+	id INTEGER NOT NULL PRIMARY KEY AUTO_INCREMENT,
+	first_name VARCHAR(128) NOT NULL,
+	last_name VARCHAR(128) NOT NULL,
+	user_id INTEGER NOT NULL,
+	CONSTRAINT FK_profile_user FOREIGN KEY (user_id)
+		REFERENCES users (id) ON DELETE CASCADE ON UPDATE RESTRICT
+) TYPE=INNODB;
+
+INSERT INTO profiles (first_name, last_name, user_id) VALUES ('first 1','last 1',1);
+INSERT INTO profiles (first_name, last_name, user_id) VALUES ('first 2','last 2',2);
+
+CREATE TABLE posts
+(
+	id INTEGER NOT NULL PRIMARY KEY AUTO_INCREMENT,
+	title VARCHAR(128) NOT NULL,
+	create_time TIMESTAMP NOT NULL,
+	author_id INTEGER NOT NULL,
+	content TEXT,
+	CONSTRAINT FK_post_author FOREIGN KEY (author_id)
+		REFERENCES users (id) ON DELETE CASCADE ON UPDATE RESTRICT
+) TYPE=INNODB;
+
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 1','2000-01-01',1,'content 1');
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 2','2000-01-02',2,'content 2');
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 3','2000-01-03',2,'content 3');
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 4','2000-01-04',2,'content 4');
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 5','2000-01-05',3,'content 5');
+
+CREATE TABLE comments
+(
+	id INTEGER NOT NULL PRIMARY KEY AUTO_INCREMENT,
+	content TEXT NOT NULL,
+	post_id INTEGER NOT NULL,
+	author_id INTEGER NOT NULL,
+	CONSTRAINT FK_post_comment FOREIGN KEY (post_id)
+		REFERENCES posts (id) ON DELETE CASCADE ON UPDATE RESTRICT,
+	CONSTRAINT FK_user_comment FOREIGN KEY (author_id)
+		REFERENCES users (id) ON DELETE CASCADE ON UPDATE RESTRICT
+) TYPE=INNODB;
+
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 1',1, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 2',1, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 3',1, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 4',2, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 5',2, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 6',3, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 7',3, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 8',3, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 9',3, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 10',5, 3);
+
+CREATE TABLE categories
+(
+	id INTEGER NOT NULL PRIMARY KEY AUTO_INCREMENT,
+	name VARCHAR(128) NOT NULL,
+	parent_id INTEGER,
+	CONSTRAINT FK_category_category FOREIGN KEY (parent_id)
+		REFERENCES categories (id) ON DELETE CASCADE ON UPDATE RESTRICT
+) TYPE=INNODB;
+
+INSERT INTO categories (name, parent_id) VALUES ('cat 1',NULL);
+INSERT INTO categories (name, parent_id) VALUES ('cat 2',NULL);
+INSERT INTO categories (name, parent_id) VALUES ('cat 3',NULL);
+INSERT INTO categories (name, parent_id) VALUES ('cat 4',1);
+INSERT INTO categories (name, parent_id) VALUES ('cat 5',1);
+INSERT INTO categories (name, parent_id) VALUES ('cat 6',5);
+INSERT INTO categories (name, parent_id) VALUES ('cat 7',5);
+
+CREATE TABLE post_category
+(
+	category_id INTEGER NOT NULL,
+	post_id INTEGER NOT NULL,
+	PRIMARY KEY (category_id, post_id),
+	CONSTRAINT FK_post_category_post FOREIGN KEY (post_id)
+		REFERENCES posts (id) ON DELETE CASCADE ON UPDATE RESTRICT,
+	CONSTRAINT FK_post_category_category FOREIGN KEY (category_id)
+		REFERENCES categories (id) ON DELETE CASCADE ON UPDATE RESTRICT
+) TYPE=INNODB;
+
+INSERT INTO post_category (category_id, post_id) VALUES (1,1);
+INSERT INTO post_category (category_id, post_id) VALUES (2,1);
+INSERT INTO post_category (category_id, post_id) VALUES (3,1);
+INSERT INTO post_category (category_id, post_id) VALUES (4,2);
+INSERT INTO post_category (category_id, post_id) VALUES (1,2);
+INSERT INTO post_category (category_id, post_id) VALUES (1,3);
+
+CREATE TABLE orders
+(
+	key1 INTEGER NOT NULL,
+	key2 INTEGER NOT NULL,
+	name VARCHAR(128),
+	PRIMARY KEY (key1, key2)
+) TYPE=INNODB;
+
+INSERT INTO orders (key1,key2,name) VALUES (1,2,'order 12');
+INSERT INTO orders (key1,key2,name) VALUES (1,3,'order 13');
+INSERT INTO orders (key1,key2,name) VALUES (2,1,'order 21');
+INSERT INTO orders (key1,key2,name) VALUES (2,2,'order 22');
+
+CREATE TABLE items
+(
+	id INTEGER NOT NULL PRIMARY KEY AUTO_INCREMENT,
+	name VARCHAR(128),
+	col1 INTEGER NOT NULL,
+	col2 INTEGER NOT NULL,
+	CONSTRAINT FK_order_item FOREIGN KEY (col1,col2)
+		REFERENCES orders (key1,key2) ON DELETE CASCADE ON UPDATE RESTRICT
+) TYPE=INNODB;
+
+INSERT INTO items (name,col1,col2) VALUES ('item 1',1,2);
+INSERT INTO items (name,col1,col2) VALUES ('item 2',1,2);
+INSERT INTO items (name,col1,col2) VALUES ('item 3',1,3);
+INSERT INTO items (name,col1,col2) VALUES ('item 4',2,2);
+INSERT INTO items (name,col1,col2) VALUES ('item 5',2,2);
+
+CREATE TABLE types
+(
+	int_col INT NOT NULL,
+	int_col2 INTEGER DEFAULT 1,
+	char_col CHAR(100) NOT NULL,
+	char_col2 VARCHAR(100) DEFAULT 'something',
+	char_col3 TEXT,
+	float_col REAL(4,3) NOT NULL,
+	float_col2 DOUBLE DEFAULT 1.23,
+	blob_col BLOB,
+	numeric_col NUMERIC(5,2) DEFAULT 33.22,
+	time TIMESTAMP DEFAULT '2002-01-01',
+	bool_col BOOL NOT NULL,
+	bool_col2 BOOLEAN DEFAULT 1
+) TYPE=INNODB;
\ No newline at end of file
diff --git a/tests/unit/data/postgres.sql b/tests/unit/data/postgres.sql
new file mode 100644
index 0000000..e46b284
--- /dev/null
+++ b/tests/unit/data/postgres.sql
@@ -0,0 +1,165 @@
+/**
+ * This is the database schema for testing PostgreSQL support of yii Active Record.
+ * To test this feature, you need to create a database named 'yii' on 'localhost'
+ * and create an account 'test/test' which owns this test database.
+ */
+CREATE SCHEMA test;
+
+CREATE TABLE test.users
+(
+	id SERIAL NOT NULL PRIMARY KEY,
+	username VARCHAR(128) NOT NULL,
+	password VARCHAR(128) NOT NULL,
+	email VARCHAR(128) NOT NULL
+);
+
+INSERT INTO test.users (username, password, email) VALUES ('user1','pass1','email1');
+INSERT INTO test.users (username, password, email) VALUES ('user2','pass2','email2');
+INSERT INTO test.users (username, password, email) VALUES ('user3','pass3','email3');
+
+CREATE TABLE test.user_friends
+(
+	id INTEGER NOT NULL,
+	friend INTEGER NOT NULL,
+	PRIMARY KEY (id, friend),
+	CONSTRAINT FK_user_id FOREIGN KEY (id)
+		REFERENCES test.users (id) ON DELETE CASCADE ON UPDATE RESTRICT,
+	CONSTRAINT FK_friend_id FOREIGN KEY (friend)
+		REFERENCES test.users (id) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO test.user_friends VALUES (1,2);
+INSERT INTO test.user_friends VALUES (1,3);
+INSERT INTO test.user_friends VALUES (2,3);
+
+CREATE TABLE test.profiles
+(
+	id SERIAL NOT NULL PRIMARY KEY,
+	first_name VARCHAR(128) NOT NULL,
+	last_name VARCHAR(128) NOT NULL,
+	user_id INTEGER NOT NULL,
+	CONSTRAINT FK_profile_user FOREIGN KEY (user_id)
+		REFERENCES test.users (id) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO test.profiles (first_name, last_name, user_id) VALUES ('first 1','last 1',1);
+INSERT INTO test.profiles (first_name, last_name, user_id) VALUES ('first 2','last 2',2);
+
+CREATE TABLE test.posts
+(
+	id SERIAL NOT NULL PRIMARY KEY,
+	title VARCHAR(128) NOT NULL,
+	create_time TIMESTAMP NOT NULL,
+	author_id INTEGER NOT NULL,
+	content TEXT,
+	CONSTRAINT FK_post_author FOREIGN KEY (author_id)
+		REFERENCES test.users (id) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO test.posts (title, create_time, author_id, content) VALUES ('post 1',TIMESTAMP '2004-10-19 10:23:54',1,'content 1');
+INSERT INTO test.posts (title, create_time, author_id, content) VALUES ('post 2',TIMESTAMP '2004-10-19 10:23:54',2,'content 2');
+INSERT INTO test.posts (title, create_time, author_id, content) VALUES ('post 3',TIMESTAMP '2004-10-19 10:23:54',2,'content 3');
+INSERT INTO test.posts (title, create_time, author_id, content) VALUES ('post 4',TIMESTAMP '2004-10-19 10:23:54',2,'content 4');
+INSERT INTO test.posts (title, create_time, author_id, content) VALUES ('post 5',TIMESTAMP '2004-10-19 10:23:54',3,'content 5');
+
+CREATE TABLE test.comments
+(
+	id SERIAL NOT NULL PRIMARY KEY,
+	content TEXT NOT NULL,
+	post_id INTEGER NOT NULL,
+	author_id INTEGER NOT NULL,
+	CONSTRAINT FK_post_comment FOREIGN KEY (post_id)
+		REFERENCES test.posts (id) ON DELETE CASCADE ON UPDATE RESTRICT,
+	CONSTRAINT FK_user_comment FOREIGN KEY (author_id)
+		REFERENCES test.users (id) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO test.comments (content, post_id, author_id) VALUES ('comment 1',1, 2);
+INSERT INTO test.comments (content, post_id, author_id) VALUES ('comment 2',1, 2);
+INSERT INTO test.comments (content, post_id, author_id) VALUES ('comment 3',1, 2);
+INSERT INTO test.comments (content, post_id, author_id) VALUES ('comment 4',2, 2);
+INSERT INTO test.comments (content, post_id, author_id) VALUES ('comment 5',2, 2);
+INSERT INTO test.comments (content, post_id, author_id) VALUES ('comment 6',3, 2);
+INSERT INTO test.comments (content, post_id, author_id) VALUES ('comment 7',3, 2);
+INSERT INTO test.comments (content, post_id, author_id) VALUES ('comment 8',3, 2);
+INSERT INTO test.comments (content, post_id, author_id) VALUES ('comment 9',3, 2);
+INSERT INTO test.comments (content, post_id, author_id) VALUES ('comment 10',5, 3);
+
+CREATE TABLE test.categories
+(
+	id SERIAL NOT NULL PRIMARY KEY,
+	name VARCHAR(128) NOT NULL,
+	parent_id INTEGER,
+	CONSTRAINT FK_category_category FOREIGN KEY (parent_id)
+		REFERENCES test.categories (id) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO test.categories (name, parent_id) VALUES ('cat 1',NULL);
+INSERT INTO test.categories (name, parent_id) VALUES ('cat 2',NULL);
+INSERT INTO test.categories (name, parent_id) VALUES ('cat 3',NULL);
+INSERT INTO test.categories (name, parent_id) VALUES ('cat 4',1);
+INSERT INTO test.categories (name, parent_id) VALUES ('cat 5',1);
+INSERT INTO test.categories (name, parent_id) VALUES ('cat 6',5);
+INSERT INTO test.categories (name, parent_id) VALUES ('cat 7',5);
+
+CREATE TABLE test.post_category
+(
+	category_id INTEGER NOT NULL,
+	post_id INTEGER NOT NULL,
+	PRIMARY KEY (category_id, post_id),
+	CONSTRAINT FK_post_category_post FOREIGN KEY (post_id)
+		REFERENCES test.posts (id) ON DELETE CASCADE ON UPDATE RESTRICT,
+	CONSTRAINT FK_post_category_category FOREIGN KEY (category_id)
+		REFERENCES test.categories (id) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO test.post_category (category_id, post_id) VALUES (1,1);
+INSERT INTO test.post_category (category_id, post_id) VALUES (2,1);
+INSERT INTO test.post_category (category_id, post_id) VALUES (3,1);
+INSERT INTO test.post_category (category_id, post_id) VALUES (4,2);
+INSERT INTO test.post_category (category_id, post_id) VALUES (1,2);
+INSERT INTO test.post_category (category_id, post_id) VALUES (1,3);
+
+CREATE TABLE test.orders
+(
+	key1 INTEGER NOT NULL,
+	key2 INTEGER NOT NULL,
+	name VARCHAR(128),
+	PRIMARY KEY (key1, key2)
+);
+
+INSERT INTO test.orders (key1,key2,name) VALUES (1,2,'order 12');
+INSERT INTO test.orders (key1,key2,name) VALUES (1,3,'order 13');
+INSERT INTO test.orders (key1,key2,name) VALUES (2,1,'order 21');
+INSERT INTO test.orders (key1,key2,name) VALUES (2,2,'order 22');
+
+CREATE TABLE test.items
+(
+	id SERIAL NOT NULL PRIMARY KEY,
+	name VARCHAR(128),
+	col1 INTEGER NOT NULL,
+	col2 INTEGER NOT NULL,
+	CONSTRAINT FK_order_item FOREIGN KEY (col1,col2)
+		REFERENCES test.orders (key1,key2) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO test.items (name,col1,col2) VALUES ('item 1',1,2);
+INSERT INTO test.items (name,col1,col2) VALUES ('item 2',1,2);
+INSERT INTO test.items (name,col1,col2) VALUES ('item 3',1,3);
+INSERT INTO test.items (name,col1,col2) VALUES ('item 4',2,2);
+INSERT INTO test.items (name,col1,col2) VALUES ('item 5',2,2);
+
+CREATE TABLE public.yii_types
+(
+	int_col INT NOT NULL,
+	int_col2 INTEGER DEFAULT 1,
+	char_col CHAR(100) NOT NULL,
+	char_col2 VARCHAR(100) DEFAULT 'something',
+	char_col3 TEXT,
+	numeric_col NUMERIC(4,3) NOT NULL,
+	real_col REAL DEFAULT 1.23,
+	blob_col BYTEA,
+	time TIMESTAMP,
+	bool_col BOOL NOT NULL,
+	bool_col2 BOOLEAN DEFAULT TRUE
+);
\ No newline at end of file
diff --git a/tests/unit/data/sqlite.sql b/tests/unit/data/sqlite.sql
new file mode 100644
index 0000000..affeca9
--- /dev/null
+++ b/tests/unit/data/sqlite.sql
@@ -0,0 +1,262 @@
+CREATE TABLE users
+(
+	id INTEGER NOT NULL PRIMARY KEY,
+	username VARCHAR(128) NOT NULL,
+	password VARCHAR(128) NOT NULL,
+	email VARCHAR(128) NOT NULL
+);
+
+INSERT INTO users(id,username,password,email) VALUES (1,'user1','pass1','email1');
+INSERT INTO users(id,username,password,email) VALUES (2,'user2','pass2','email2');
+INSERT INTO users(id,username,password,email) VALUES (3,'user3','pass3','email3');
+INSERT INTO users(id,username,password,email) VALUES (4,'user4','pass4','email4');
+
+CREATE TABLE groups
+(
+	id INTEGER NOT NULL PRIMARY KEY,
+	name VARCHAR(128) NOT NULL
+);
+
+INSERT INTO groups(id,name) VALUES (1,'group1');
+INSERT INTO groups(id,name) VALUES (2,'group2');
+INSERT INTO groups(id,name) VALUES (3,'group3');
+INSERT INTO groups(id,name) VALUES (4,'group4');
+INSERT INTO groups(id,name) VALUES (5,'group5');
+INSERT INTO groups(id,name) VALUES (6,'group6');
+
+CREATE TABLE groups_descriptions
+(
+	group_id INTEGER NOT NULL PRIMARY KEY,
+	name VARCHAR(128) NOT NULL
+);
+
+INSERT INTO groups_descriptions(group_id,name) VALUES (1,'room1');
+INSERT INTO groups_descriptions(group_id,name) VALUES (2,'room2');
+INSERT INTO groups_descriptions(group_id,name) VALUES (3,'room3');
+INSERT INTO groups_descriptions(group_id,name) VALUES (4,'room4');
+
+CREATE TABLE roles
+(
+	user_id INTEGER NOT NULL,
+	group_id INTEGER NOT NULL,
+	name VARCHAR(128) NOT NULL,
+	PRIMARY KEY(user_id,group_id)
+);
+
+INSERT INTO roles(user_id,group_id,name) VALUES (1,1,'dev');
+INSERT INTO roles(user_id,group_id,name) VALUES (1,2,'user');
+INSERT INTO roles(user_id,group_id,name) VALUES (2,1,'dev');
+INSERT INTO roles(user_id,group_id,name) VALUES (2,3,'user');
+
+CREATE TABLE mentorships
+(
+	teacher_id INTEGER NOT NULL,
+	student_id INTEGER NOT NULL,
+	progress VARCHAR(128) NOT NULL,
+	PRIMARY KEY(teacher_id,student_id)
+);
+
+INSERT INTO mentorships(teacher_id,student_id,progress) VALUES (1,3,'good');
+INSERT INTO mentorships(teacher_id,student_id,progress) VALUES (2,4,'average');
+
+CREATE TABLE profiles
+(
+	id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+	first_name VARCHAR(128) NOT NULL,
+	last_name VARCHAR(128) NOT NULL,
+	user_id INTEGER NOT NULL,
+	CONSTRAINT FK_profile_user FOREIGN KEY (user_id)
+		REFERENCES users (id) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO profiles (first_name, last_name, user_id) VALUES ('first 1','last 1',1);
+INSERT INTO profiles (first_name, last_name, user_id) VALUES ('first 2','last 2',2);
+
+CREATE TABLE posts
+(
+	id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+	title VARCHAR(128) NOT NULL,
+	create_time TIMESTAMP NOT NULL,
+	author_id INTEGER NOT NULL,
+	content TEXT,
+	CONSTRAINT FK_post_author FOREIGN KEY (author_id)
+		REFERENCES users (id) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 1',100000,1,'content 1');
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 2',100001,2,'content 2');
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 3',100002,2,'content 3');
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 4',100003,2,'content 4');
+INSERT INTO posts (title, create_time, author_id, content) VALUES ('post 5',100004,3,'content 5');
+
+
+CREATE TABLE posts_nofk
+(
+	id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+	title VARCHAR(128) NOT NULL,
+	create_time TIMESTAMP NOT NULL,
+	author_id INTEGER NOT NULL,
+	content TEXT
+);
+
+INSERT INTO posts_nofk (title, create_time, author_id, content) VALUES ('post 1',100000,1,'content 1');
+INSERT INTO posts_nofk (title, create_time, author_id, content) VALUES ('post 2',100001,2,'content 2');
+INSERT INTO posts_nofk (title, create_time, author_id, content) VALUES ('post 3',100002,2,'content 3');
+INSERT INTO posts_nofk (title, create_time, author_id, content) VALUES ('post 4',100003,2,'content 4');
+INSERT INTO posts_nofk (title, create_time, author_id, content) VALUES ('post 5',100004,3,'content 5');
+
+
+CREATE TABLE comments
+(
+	id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+	content TEXT NOT NULL,
+	post_id INTEGER NOT NULL,
+	author_id INTEGER NOT NULL,
+	CONSTRAINT FK_post_comment FOREIGN KEY (post_id)
+		REFERENCES posts (id) ON DELETE CASCADE ON UPDATE RESTRICT,
+	CONSTRAINT FK_user_comment FOREIGN KEY (author_id)
+		REFERENCES users (id) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 1',1, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 2',1, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 3',1, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 4',2, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 5',2, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 6',3, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 7',3, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 8',3, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 9',3, 2);
+INSERT INTO comments (content, post_id, author_id) VALUES ('comment 10',5, 3);
+
+CREATE TABLE categories
+(
+	id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+	name VARCHAR(128) NOT NULL,
+	parent_id INTEGER,
+	CONSTRAINT FK_category_category FOREIGN KEY (parent_id)
+		REFERENCES categories (id) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO categories (name, parent_id) VALUES ('cat 1',NULL);
+INSERT INTO categories (name, parent_id) VALUES ('cat 2',NULL);
+INSERT INTO categories (name, parent_id) VALUES ('cat 3',NULL);
+INSERT INTO categories (name, parent_id) VALUES ('cat 4',1);
+INSERT INTO categories (name, parent_id) VALUES ('cat 5',1);
+INSERT INTO categories (name, parent_id) VALUES ('cat 6',5);
+INSERT INTO categories (name, parent_id) VALUES ('cat 7',5);
+
+CREATE TABLE post_category
+(
+	category_id INTEGER NOT NULL,
+	post_id INTEGER NOT NULL,
+	PRIMARY KEY (category_id, post_id),
+	CONSTRAINT FK_post_category_post FOREIGN KEY (post_id)
+		REFERENCES posts (id) ON DELETE CASCADE ON UPDATE RESTRICT,
+	CONSTRAINT FK_post_category_category FOREIGN KEY (category_id)
+		REFERENCES categories (id) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO post_category (category_id, post_id) VALUES (1,1);
+INSERT INTO post_category (category_id, post_id) VALUES (2,1);
+INSERT INTO post_category (category_id, post_id) VALUES (3,1);
+INSERT INTO post_category (category_id, post_id) VALUES (4,2);
+INSERT INTO post_category (category_id, post_id) VALUES (1,2);
+INSERT INTO post_category (category_id, post_id) VALUES (1,3);
+
+CREATE TABLE orders
+(
+	key1 INTEGER NOT NULL,
+	key2 INTEGER NOT NULL,
+	name VARCHAR(128),
+	PRIMARY KEY (key1, key2)
+);
+
+INSERT INTO orders (key1,key2,name) VALUES (1,2,'order 12');
+INSERT INTO orders (key1,key2,name) VALUES (1,3,'order 13');
+INSERT INTO orders (key1,key2,name) VALUES (2,1,'order 21');
+INSERT INTO orders (key1,key2,name) VALUES (2,2,'order 22');
+
+CREATE TABLE items
+(
+	id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+	name VARCHAR(128),
+	col1 INTEGER NOT NULL,
+	col2 INTEGER NOT NULL,
+	CONSTRAINT FK_order_item FOREIGN KEY (col1,col2)
+		REFERENCES orders (key1,key2) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO items (name,col1,col2) VALUES ('item 1',1,2);
+INSERT INTO items (name,col1,col2) VALUES ('item 2',1,2);
+INSERT INTO items (name,col1,col2) VALUES ('item 3',1,3);
+INSERT INTO items (name,col1,col2) VALUES ('item 4',2,2);
+INSERT INTO items (name,col1,col2) VALUES ('item 5',2,2);
+
+CREATE TABLE types
+(
+	int_col INT NOT NULL,
+	int_col2 INTEGER DEFAULT 1,
+	char_col CHAR(100) NOT NULL,
+	char_col2 VARCHAR(100) DEFAULT 'something',
+	char_col3 TEXT,
+	float_col REAL(4,3) NOT NULL,
+	float_col2 DOUBLE DEFAULT 1.23,
+	blob_col BLOB,
+	numeric_col NUMERIC(5,2) DEFAULT 33.22,
+	time TIMESTAMP DEFAULT 123,
+	bool_col BOOL NOT NULL,
+	bool_col2 BOOLEAN DEFAULT 1,
+	null_col INTEGER DEFAULT NULL
+);
+
+CREATE TABLE Content
+(
+	id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+	class VARCHAR(128),
+	parentID INTEGER NOT NULL,
+	ownerID INTEGER NOT NULL,
+	title VARCHAR(100),
+	CONSTRAINT FK_content_user FOREIGN KEY (ownerID)
+		REFERENCES users (id) ON DELETE CASCADE ON UPDATE RESTRICT
+	CONSTRAINT FK_content_parent FOREIGN KEY (parentID)
+		REFERENCES Content (id) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO Content (class,parentID,ownerID,title) VALUES ('Article',-1,1,'article 1');
+INSERT INTO Content (class,parentID,ownerID,title) VALUES ('Article',-1,2,'article 2');
+INSERT INTO Content (class,parentID,ownerID,title) VALUES ('Comment',1,1,'comment 1');
+INSERT INTO Content (class,parentID,ownerID,title) VALUES ('Article',-1,2,'article 3');
+INSERT INTO Content (class,parentID,ownerID,title) VALUES ('Comment',4,2,'comment 2');
+INSERT INTO Content (class,parentID,ownerID,title) VALUES ('Comment',4,1,'comment 3');
+
+CREATE TABLE Article
+(
+	id INTEGER NOT NULL PRIMARY KEY,
+	authorID INTEGER NOT NULL,
+	body TEXT,
+	CONSTRAINT FK_article_content FOREIGN KEY (id)
+		REFERENCES Content (id) ON DELETE CASCADE ON UPDATE RESTRICT
+	CONSTRAINT FK_article_author FOREIGN KEY (authorID)
+		REFERENCES users (id) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO Article (id,authorID,body) VALUES (1,1,'content for article 1');
+INSERT INTO Article (id,authorID,body) VALUES (2,2,'content for article 2');
+INSERT INTO Article (id,authorID,body) VALUES (4,1,'content for article 3');
+
+CREATE TABLE Comment
+(
+	id INTEGER NOT NULL PRIMARY KEY,
+	authorID INTEGER NOT NULL,
+	body TEXT,
+	CONSTRAINT FK_comment_content FOREIGN KEY (id)
+		REFERENCES Content (id) ON DELETE CASCADE ON UPDATE RESTRICT
+	CONSTRAINT FK_article_author FOREIGN KEY (authorID)
+		REFERENCES users (id) ON DELETE CASCADE ON UPDATE RESTRICT
+);
+
+INSERT INTO Comment (id,authorID,body) VALUES (3,1,'content for comment 1');
+INSERT INTO Comment (id,authorID,body) VALUES (5,1,'content for comment 2');
+INSERT INTO Comment (id,authorID,body) VALUES (6,1,'content for comment 3');
+
diff --git a/tests/unit/framework/base/ComponentTest.php b/tests/unit/framework/base/ComponentTest.php
index 53bc35d..6327b15 100644
--- a/tests/unit/framework/base/ComponentTest.php
+++ b/tests/unit/framework/base/ComponentTest.php
@@ -11,7 +11,7 @@ function globalEventHandler2($event)
 	$event->handled=true;
 }
 
-class ComponentTest extends \yii\test\TestCase
+class ComponentTest extends TestCase
 {
 	protected $component;
 
diff --git a/tests/unit/framework/base/DictionaryTest.php b/tests/unit/framework/base/DictionaryTest.php
index de3f7de..a33e643 100644
--- a/tests/unit/framework/base/DictionaryTest.php
+++ b/tests/unit/framework/base/DictionaryTest.php
@@ -1,18 +1,20 @@
 <?php
 
+use yii\base\Dictionary;
+
 class MapItem
 {
 	public $data='data';
 }
 
-class DictionaryTest extends \yii\test\TestCase
+class DictionaryTest extends TestCase
 {
 	protected $dictionary;
 	protected $item1,$item2,$item3;
 
 	public function setUp()
 	{
-		$this->dictionary=new \yii\base\Dictionary;
+		$this->dictionary=new Dictionary;
 		$this->item1=new MapItem;
 		$this->item2=new MapItem;
 		$this->item3=new MapItem;
@@ -31,9 +33,9 @@ class DictionaryTest extends \yii\test\TestCase
 	public function testConstruct()
 	{
 		$a=array(1,2,'key3'=>3);
-		$dictionary=new \yii\base\Dictionary($a);
+		$dictionary=new Dictionary($a);
 		$this->assertEquals(3,$dictionary->getCount());
-		$dictionary2=new \yii\base\Dictionary($this->dictionary);
+		$dictionary2=new Dictionary($this->dictionary);
 		$this->assertEquals(2,$dictionary2->getCount());
 	}
 
@@ -97,8 +99,8 @@ class DictionaryTest extends \yii\test\TestCase
 		$a=array('a'=>'v1','v2',array('2'),'c'=>array('3','c'=>'a'));
 		$b=array('v22','a'=>'v11',array('2'),'c'=>array('c'=>'3','a'));
 		$c=array('a'=>'v11','v2',array('2'),'c'=>array('3','c'=>'3','a'),'v22',array('2'));
-		$dictionary=new \yii\base\Dictionary($a);
-		$dictionary2=new \yii\base\Dictionary($b);
+		$dictionary=new Dictionary($a);
+		$dictionary2=new Dictionary($b);
 		$dictionary->mergeWith($dictionary2);
 		$this->assertTrue($dictionary->toArray()===$c);
 
@@ -112,7 +114,7 @@ class DictionaryTest extends \yii\test\TestCase
 	}
 
 	public function testRecursiveMergeWithTraversable(){
-		$dictionary = new \yii\base\Dictionary();
+		$dictionary = new Dictionary();
 		$obj = new ArrayObject(array(
 			'k1' => $this->item1,
 			'k2' => $this->item2,
@@ -176,13 +178,13 @@ class DictionaryTest extends \yii\test\TestCase
 
 	public function testToArray()
 	{
-		$dictionary = new \yii\base\Dictionary(array('key' => 'value'));
+		$dictionary = new Dictionary(array('key' => 'value'));
 		$this->assertEquals(array('key' => 'value'), $dictionary->toArray());
 	}
 
 	public function testIteratorCurrent()
 	{
-		$dictionary = new \yii\base\Dictionary(array('key1' => 'value1', 'key2' => 'value2'));
+		$dictionary = new Dictionary(array('key1' => 'value1', 'key2' => 'value2'));
 		$val = $dictionary->getIterator()->current();
 		$this->assertEquals('value1', $val);
 	}
diff --git a/tests/unit/framework/base/VectorTest.php b/tests/unit/framework/base/VectorTest.php
index 65901d6..b8bf1a5 100644
--- a/tests/unit/framework/base/VectorTest.php
+++ b/tests/unit/framework/base/VectorTest.php
@@ -1,18 +1,20 @@
 <?php
 
+use yii\base\Vector;
+
 class ListItem
 {
 	public $data='data';
 }
 
-class VectorTest extends \yii\test\TestCase
+class VectorTest extends TestCase
 {
 	protected $vector;
 	protected $item1, $item2, $item3;
 
 	public function setUp()
 	{
-		$this->vector=new \yii\base\Vector;
+		$this->vector=new Vector;
 		$this->item1=new ListItem;
 		$this->item2=new ListItem;
 		$this->item3=new ListItem;
@@ -31,9 +33,9 @@ class VectorTest extends \yii\test\TestCase
 	public function testConstruct()
 	{
 		$a=array(1,2,3);
-		$vector=new \yii\base\Vector($a);
+		$vector=new Vector($a);
 		$this->assertEquals(3,$vector->getCount());
-		$vector2=new \yii\base\Vector($this->vector);
+		$vector2=new Vector($this->vector);
 		$this->assertEquals(2,$vector2->getCount());
 	}
 
@@ -163,28 +165,28 @@ class VectorTest extends \yii\test\TestCase
 
 	public function testOffsetSetAdd()
 	{
-		$vector = new \yii\base\Vector(array(1, 2, 3));
+		$vector = new Vector(array(1, 2, 3));
 		$vector->offsetSet(null, 4);
 		$this->assertEquals(array(1, 2, 3, 4), $vector->toArray());
 	}
 
 	public function testOffsetSetReplace()
 	{
-		$vector = new \yii\base\Vector(array(1, 2, 3));
+		$vector = new Vector(array(1, 2, 3));
 		$vector->offsetSet(1, 4);
 		$this->assertEquals(array(1, 4, 3), $vector->toArray());
 	}
 
 	public function testOffsetUnset()
 	{
-		$vector = new \yii\base\Vector(array(1, 2, 3));
+		$vector = new Vector(array(1, 2, 3));
 		$vector->offsetUnset(1);
 		$this->assertEquals(array(1, 3), $vector->toArray());
 	}
 
 	public function testIteratorCurrent()
 	{
-		$vector = new \yii\base\Vector(array('value1', 'value2'));
+		$vector = new Vector(array('value1', 'value2'));
 		$val = $vector->getIterator()->current();
 		$this->assertEquals('value1', $val);
 	}
diff --git a/tests/unit/framework/db/dao/ConnectionTest.php b/tests/unit/framework/db/dao/ConnectionTest.php
new file mode 100644
index 0000000..d3dbbf8
--- /dev/null
+++ b/tests/unit/framework/db/dao/ConnectionTest.php
@@ -0,0 +1,88 @@
+<?php
+
+use yii\db\dao\Connection;
+
+class ConnectionTest extends TestCase
+{
+	function setUp()
+	{
+		if(!extension_loaded('pdo') || !extension_loaded('pdo_mysql'))
+			$this->markTestSkipped('PDO and MySQL extensions are required.');
+	}
+
+	function testConstruct()
+	{
+		$params = $this->getParam('mysql');
+		$connection = new Connection($params['dsn'], $params['username'], $params['password']);
+		$this->assertEquals($params['dsn'], $connection->dsn);
+		$this->assertEquals($params['username'], $connection->username);
+		$this->assertEquals($params['password'], $connection->password);
+	}
+
+	function testOpenClose()
+	{
+		$params = $this->getParam('mysql');
+		$connection = new Connection($params['dsn'], $params['username'], $params['password']);
+		$this->assertFalse($connection->active);
+		$this->assertEquals(null, $connection->pdo);
+
+		$connection->open();
+		$this->assertTrue($connection->active);
+		$this->assertTrue($connection->pdo instanceof PDO);
+
+		$connection->close();
+		$this->assertFalse($connection->active);
+		$this->assertEquals(null, $connection->pdo);
+
+		$connection = new Connection('unknown::memory:');
+		$this->setExpectedException('yii\db\Exception');
+		$connection->open();
+	}
+
+	/*
+	function testCreateCommand()
+	{
+		$sql='SELECT * FROM posts';
+		$this->connection->active=true;
+		$this->connection->pdoInstance->exec(file_get_contents(dirname(__FILE__).'/data/sqlite.sql'));
+		$command=$this->connection->createCommand($sql);
+		$this->assertTrue($command instanceof CDbCommand);
+	}
+
+	function testLastInsertID()
+	{
+	    $this->connection->active=true;
+	    $this->connection->pdoInstance->exec(file_get_contents(dirname(__FILE__).'/data/sqlite.sql'));
+		$sql='INSERT INTO posts(title,create_time,author_id) VALUES(\'test post\',11000,1)';
+		$this->connection->createCommand($sql)->execute();
+		$this->assertEquals($this->connection->lastInsertID,6);
+	}
+
+	function testQuoteValue()
+	{
+	    $this->connection->active=true;
+	    $this->connection->pdoInstance->exec(file_get_contents(dirname(__FILE__).'/data/sqlite.sql'));
+		$str="this is 'my' name";
+		$expectedStr="'this is ''my'' name'";
+		$this->assertEquals($expectedStr,$this->connection->quoteValue($str));
+	}
+
+	function testColumnNameCase()
+	{
+	    $this->connection->active=true;
+	    $this->connection->pdoInstance->exec(file_get_contents(dirname(__FILE__).'/data/sqlite.sql'));
+		$this->assertEquals(PDO::CASE_NATURAL,$this->connection->ColumnCase);
+		$this->connection->columnCase=PDO::CASE_LOWER;
+		$this->assertEquals(PDO::CASE_LOWER,$this->connection->ColumnCase);
+	}
+
+	function testNullConversion()
+	{
+	    $this->connection->active=true;
+	    $this->connection->pdoInstance->exec(file_get_contents(dirname(__FILE__).'/data/sqlite.sql'));
+		$this->assertEquals(PDO::NULL_NATURAL,$this->connection->NullConversion);
+		$this->connection->nullConversion=PDO::NULL_EMPTY_STRING;
+		$this->assertEquals(PDO::NULL_EMPTY_STRING,$this->connection->NullConversion);
+	}
+	*/
+}