code refactoring.

framework/YiiBase.php

@@ -381,7 +381,7 @@ class YiiBase
 	 * @param string $message the message to be logged.
 	 * @param string $category the category of the message.
 	 */
-	public function error($message, $category = 'application')
+	public static function error($message, $category = 'application')
 	{
 		self::getLogger()->error($message, $category);
 	}
@@ -393,7 +393,7 @@ class YiiBase
 	 * @param string $message the message to be logged.
 	 * @param string $category the category of the message.
 	 */
-	public function warning($message, $category = 'application')
+	public static function warning($message, $category = 'application')
 	{
 		self::getLogger()->warning($message, $category);
 	}
@@ -405,7 +405,7 @@ class YiiBase
 	 * @param string $message the message to be logged.
 	 * @param string $category the category of the message.
 	 */
-	public function info($message, $category = 'application')
+	public static function info($message, $category = 'application')
 	{
 		self::getLogger()->info($message, $category);
 	}

framework/base/Dictionary.php

@@ -114,8 +114,7 @@ class Dictionary extends Object implements \IteratorAggregate, \ArrayAccess, \Co
 	{
 		if ($key === null) {
 			$this->_d[] = $value;
-		}
-		else {
+		} else {
 			$this->_d[$key] = $value;
 		}
 	}
@@ -132,8 +131,7 @@ class Dictionary extends Object implements \IteratorAggregate, \ArrayAccess, \Co
 			$value = $this->_d[$key];
 			unset($this->_d[$key]);
 			return $value;
-		}
-		else { // the value is null
+		} else { // the value is null
 			unset($this->_d[$key]);
 			return null;
 		}
@@ -194,8 +192,7 @@ class Dictionary extends Object implements \IteratorAggregate, \ArrayAccess, \Co
 			foreach ($data as $key => $value) {
 				$this->add($key, $value);
 			}
-		}
-		else {
+		} else {
 			throw new Exception('Data must be either an array or an object implementing Traversable.');
 		}
 	}
@@ -230,18 +227,15 @@ class Dictionary extends Object implements \IteratorAggregate, \ArrayAccess, \Co
 						$d[$key] = $value;
 					}
 					$this->_d = self::mergeArray($this->_d, $d);
-				}
-				else {
+				} else {
 					$this->_d = self::mergeArray($this->_d, $data);
 				}
-			}
-			else {
+			} else {
 				foreach($data as $key => $value) {
 					$this->add($key, $value);
 				}
 			}
-		}
-		else {
+		} else {
 			throw new Exception('Dictionary data must be an array or an object implementing Traversable.');
 		}
 	}
@@ -317,12 +311,11 @@ class Dictionary extends Object implements \IteratorAggregate, \ArrayAccess, \Co
 		foreach($b as $k=>$v) {
 			if(is_integer($k)) {
 				isset($a[$k]) ? $a[] = $v : $a[$k] = $v;
-			}
-			elseif(is_array($v) && isset($a[$k]) && is_array($a[$k])) {
+			} elseif(is_array($v) && isset($a[$k]) && is_array($a[$k])) {
 				$a[$k] = self::mergeArray($a[$k], $v);
-			}
-			else
+			} else {
 				$a[$k] = $v;
+			}
 		}
 		return $a;
 	}

framework/base/Model.php

@@ -367,8 +367,7 @@ class Model extends Component implements Initable, \IteratorAggregate, \ArrayAcc
 			if (isset($rule[0], $rule[1])) {  // attributes, validator type
 				$validator = \yii\validators\Validator::createValidator($rule[1], $this, $rule[0], array_slice($rule, 2));
 				$validators->add($validator);
-			}
-			else {
+			} else {
 				throw new Exception('Invalid validation rule: a rule must specify both attribute names and validator type.');
 			}
 		}
@@ -456,8 +455,7 @@ class Model extends Component implements Initable, \IteratorAggregate, \ArrayAcc
 	{
 		if ($attribute === null) {
 			return $this->_errors === null ? array() : $this->_errors;
-		}
-		else {
+		} else {
 			return isset($this->_errors[$attribute]) ? $this->_errors[$attribute] : array();
 		}
 	}
@@ -496,8 +494,7 @@ class Model extends Component implements Initable, \IteratorAggregate, \ArrayAcc
 				foreach ($error as $e) {
 					$this->_errors[$attribute][] = $e;
 				}
-			}
-			else {
+			} else {
 				$this->_errors[$attribute][] = $error;
 			}
 		}
@@ -511,8 +508,7 @@ class Model extends Component implements Initable, \IteratorAggregate, \ArrayAcc
 	{
 		if ($attribute === null) {
 			$this->_errors = array();
-		}
-		else {
+		} else {
 			unset($this->_errors[$attribute]);
 		}
 	}
@@ -547,8 +543,7 @@ class Model extends Component implements Initable, \IteratorAggregate, \ArrayAcc
 					$values[$name] = $this->$name;
 				}
 			}
-		}
-		else {
+		} else {
 			foreach ($this->attributeNames() as $name) {
 				$values[$name] = $this->$name;
 			}
@@ -572,8 +567,7 @@ class Model extends Component implements Initable, \IteratorAggregate, \ArrayAcc
 			foreach ($values as $name => $value) {
 				if (isset($attributes[$name])) {
 					$this->$name = $value;
-				}
-				elseif ($safeOnly) {
+				} elseif ($safeOnly) {
 					$this->onUnsafeAttribute($name, $value);
 				}
 			}
@@ -639,8 +633,7 @@ class Model extends Component implements Initable, \IteratorAggregate, \ArrayAcc
 				foreach ($validator->attributes as $name) {
 					$unsafe[] = $name;
 				}
-			}
-			else {
+			} else {
 				foreach ($validator->attributes as $name) {
 					$attributes[$name] = true;
 				}

framework/base/Vector.php

@@ -103,11 +103,9 @@ class Vector extends Object implements \IteratorAggregate, \ArrayAccess, \Counta
 	{
 		if (isset($this->_d[$index])) {
 			return $this->_d[$index];
-		}
-		elseif ($index >= 0 && $index < $this->_c) { // in case the value is null
+		} elseif ($index >= 0 && $index < $this->_c) { // in case the value is null
 			return $this->_d[$index];
-		}
-		else {
+		} else {
 			throw new Exception('Index out of range: ' . $index);
 		}
 	}
@@ -136,12 +134,10 @@ class Vector extends Object implements \IteratorAggregate, \ArrayAccess, \Counta
 	{
 		if ($index === $this->_c) {
 			$this->_d[$this->_c++] = $item;
-		}
-		elseif ($index >= 0 && $index < $this->_c) {
+		} elseif ($index >= 0 && $index < $this->_c) {
 			array_splice($this->_d, $index, 0, array($item));
 			$this->_c++;
-		}
-		else {
+		} else {
 			throw new Exception('Index out of range: ' . $index);
 		}
 	}
@@ -157,12 +153,10 @@ class Vector extends Object implements \IteratorAggregate, \ArrayAccess, \Counta
 	 */
 	public function remove($item)
 	{
-		if (($index = $this->indexOf($item)) >= 0)
-		{
+		if (($index = $this->indexOf($item)) >= 0) {
 			$this->removeAt($index);
 			return $index;
-		}
-		else {
+		} else {
 			return false;
 		}
 	}
@@ -179,14 +173,12 @@ class Vector extends Object implements \IteratorAggregate, \ArrayAccess, \Counta
 			$this->_c--;
 			if ($index === $this->_c) {
 				return array_pop($this->_d);
-			}
-			else {
+			} else {
 				$item = $this->_d[$index];
 				array_splice($this->_d, $index, 1);
 				return $item;
 			}
-		}
-		else {
+		} else {
 			throw new Exception('Index out of range: ' . $index);
 		}
 	}
@@ -260,8 +252,7 @@ class Vector extends Object implements \IteratorAggregate, \ArrayAccess, \Counta
 			foreach ($data as $item) {
 				$this->add($item);
 			}
-		}
-		else {
+		} else {
 			throw new Exception('Data must be either an array or an object implementing Traversable.');
 		}
 	}
@@ -281,8 +272,7 @@ class Vector extends Object implements \IteratorAggregate, \ArrayAccess, \Counta
 			foreach ($data as $item) {
 				$this->add($item);
 			}
-		}
-		else {
+		} else {
 			throw new Exception('Data must be either an array or an object implementing Traversable.');
 		}
 	}
@@ -328,8 +318,7 @@ class Vector extends Object implements \IteratorAggregate, \ArrayAccess, \Counta
 	{
 		if ($offset === null || $offset === $this->_c) {
 			$this->insertAt($this->_c, $item);
-		}
-		else {
+		} else {
 			$this->removeAt($offset);
 			$this->insertAt($offset, $item);
 		}

framework/db/Exception.php

@@ -11,7 +11,7 @@
 namespace yii\db;
 
 /**
- * CDbException represents an exception that is caused by some DB-related operations.
+ * Exception represents an exception that is caused by some DB-related operations.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
@@ -20,8 +20,7 @@ class Exception extends \yii\base\Exception
 {
 	/**
 	 * @var mixed the error info provided by a PDO exception. This is the same as returned
-	 * by {@link http://www.php.net/manual/en/pdo.errorinfo.php PDO::errorInfo}.
-	 * @since 1.1.4
+	 * by [PDO::errorInfo](http://www.php.net/manual/en/pdo.errorinfo.php).
 	 */
 	public $errorInfo;
 

framework/db/Migration.php

@@ -46,14 +46,13 @@ abstract class CDbMigration extends CComponent
 		$transaction = $this->getDbConnection()->beginTransaction();
 		try
 		{
-			if ($this->safeUp() === false)
-			{
+			if ($this->safeUp() === false) {
 				$transaction->rollBack();
 				return false;
 			}
 			$transaction->commit();
 		}
-		catch(Exception $e)
+		catch (Exception $e)
 		{
 			echo "Exception: " . $e->getMessage() . ' (' . $e->getFile() . ':' . $e->getLine() . ")\n";
 			echo $e->getTraceAsString() . "\n";
@@ -73,14 +72,13 @@ abstract class CDbMigration extends CComponent
 		$transaction = $this->getDbConnection()->beginTransaction();
 		try
 		{
-			if ($this->safeDown() === false)
-			{
+			if ($this->safeDown() === false) {
 				$transaction->rollBack();
 				return false;
 			}
 			$transaction->commit();
 		}
-		catch(Exception $e)
+		catch (Exception $e)
 		{
 			echo "Exception: " . $e->getMessage() . ' (' . $e->getFile() . ':' . $e->getLine() . ")\n";
 			echo $e->getTraceAsString() . "\n";
@@ -125,8 +123,7 @@ abstract class CDbMigration extends CComponent
 	 */
 	public function getDbConnection()
 	{
-		if ($this->_db === null)
-		{
+		if ($this->_db === null) {
 			$this->_db = Yii::app()->getComponent('db');
 			if (!$this->_db instanceof CDbConnection)
 				throw new CException(Yii::t('yii', 'The "db" application component must be configured to be a CDbConnection object.'));

framework/db/dao/Command.php

 <?php
 /**
- * This file contains the Command class.
+ * Command class file.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @link http://www.yiiframework.com/
@@ -16,30 +16,28 @@ use yii\db\Exception;
  * Command represents a SQL statement to be executed against a database.
  *
  * A command object is usually created by calling [[Connection::createCommand]].
- * The SQL statement it represents can be set via the [[text]] property.
+ * The SQL statement it represents can be set via the [[sql]] property.
  *
- * To execute a non-query SQL (such as insert, delete, update), call [[execute]].
- * To execute an SQL statement that returns result data set (such as SELECT),
+ * To execute a non-query SQL (such as INSERT, DELETE, UPDATE), call [[execute]].
+ * To execute a SQL statement that returns result data set (such as SELECT),
  * use [[query]], [[queryRow]], [[queryColumn]], or [[queryScalar]].
  *
- * If an SQL statement returns results (such as a SELECT SQL), the results
- * can be accessed via the returned {@link CDbDataReader}.
- *
- * Command supports SQL statment preparation and parameter binding.
- * Call {@link bindParam} to bind a PHP variable to a parameter in SQL.
- * Call {@link bindValue} to bind a value to an SQL parameter.
+ * Command supports SQL statement preparation and parameter binding.
+ * Call [[bindValue]] to bind a value to a SQL parameter;
+ * Call [[bindParam]] to bind a PHP variable to a SQL parameter.
  * When binding a parameter, the SQL statement is automatically prepared.
- * You may also call {@link prepare} to explicitly prepare an SQL statement.
+ * You may also call [[prepare]] to explicitly prepare a SQL statement.
+ *
+ * Command can also be used as a query builder that builds and executes a SQL statement
+ * from code fragments. For example,
  *
- * Starting from version 1.1.6, Command can also be used as a query builder
- * that builds a SQL statement from code fragments. For example,
- * <pre>
+ * ~~~
  * $user = \Yii::app()->db->createCommand()
  *     ->select('username, password')
  *     ->from('tbl_user')
  *     ->where('id=:id', array(':id'=>1))
  *     ->queryRow();
- * </pre>
+ * ~~~
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
@@ -50,24 +48,36 @@ class Command extends \yii\base\Component
 	 * @var array the parameters (name=>value) to be bound to the current query.
 	 */
 	public $params = array();
-
+	/**
+	 * @var Connection the DB connection that this command is associated with
+	 */
 	public $connection;
+	/**
+	 * @var Query the database query that this command is currently representing
+	 */
 	public $query;
+	/**
+	 * @var \PDOStatement the PDOStatement object that this command contains
+	 */
 	public $pdoStatement;
-
-	private $_sql;
-	private $_paramLog = array();
 	/**
-	 * Set the default fetch mode for this statement
-	 * @param mixed $mode fetch mode
-	 * @return Command
+	 * @var mixed the default fetch mode for this command.
 	 * @see http://www.php.net/manual/en/function.PDOStatement-setFetchMode.php
 	 */
 	public $fetchMode = \PDO::FETCH_ASSOC;
 
 	/**
+	 * @var string the SQL statement that this command represents
+	 */
+	private $_sql;
+	/**
+	 * @var array the parameter log information
+	 */
+	private $_paramLog = array();
+
+	/**
 	 * Constructor.
-	 * @param CDbConnection $connection the database connection
+	 * @param Connection $connection the database connection
 	 * @param mixed $query the DB query to be executed. This can be either
 	 * a string representing a SQL statement, or an array whose name-value pairs
 	 * will be used to set the corresponding properties of the created command object.
@@ -91,13 +101,11 @@ class Command extends \yii\base\Component
 		$this->connection = $connection;
 		if (is_object($query)) {
 			$this->query = $query;
-		}
-		else {
+		} else {
 			$this->query = new Query;
 			if (is_array($query)) {
 				$this->query->fromArray($query);
-			}
-			else {
+			} else {
 				$this->_sql = $query;
 			}
 		}
@@ -109,15 +117,14 @@ class Command extends \yii\base\Component
 	 * multiple times for building different queries.
 	 * Calling this method will clean up all internal states of the command object.
 	 * @return Command this command instance
-	 * @since 1.1.6
 	 */
 	public function reset()
 	{
-		$this->_sql = null;
 		$this->query = new Query;
 		$this->pdoStatement = null;
-		$this->_paramLog = array();
 		$this->params = array();
+		$this->_paramLog = array();
+		$this->_sql = null;
 		return $this;
 	}
 
@@ -135,15 +142,14 @@ class Command extends \yii\base\Component
 	/**
 	 * Specifies the SQL statement to be executed.
 	 * Any previous execution will be terminated or cancel.
-	 * @param string $value the SQL statement to be executed
+	 * @param string $value the SQL statement to be set.
 	 * @return Command this command instance
 	 */
 	public function setSql($value)
 	{
-		if ($this->connection->tablePrefix !== null && strpos($value, '{') !== false) {
+		if ($this->connection->tablePrefix !== null && strpos($value, '{{') !== false) {
 			$this->_sql = preg_replace('/{{(.*?)}}/', $this->connection->tablePrefix . '\1', $value);
-		}
-		else {
+		} else {
 			$this->_sql = $value;
 		}
 		$this->cancel();
@@ -160,15 +166,16 @@ class Command extends \yii\base\Component
 	public function prepare()
 	{
 		if ($this->pdoStatement == null) {
+			$sql = $this->getSql();
 			try {
-				$this->pdoStatement = $this->connection->pdo->prepare($this->getSql());
+				$this->pdoStatement = $this->connection->pdo->prepare($sql);
 				$this->_paramLog = array();
 			}
 			catch(\Exception $e) {
-				\Yii::log('Error in preparing SQL: ' . $this->getSql(), CLogger::LEVEL_ERROR, 'system.db.Command');
+				\Yii::error("Failed to prepare SQL ($sql): " . $e->getMessage(), __CLASS__);
                 $errorInfo = $e instanceof \PDOException ? $e->errorInfo : null;
-				throw new Exception('Unable to prepare the SQL statement: {error}',
-					array('{error}' => $e->getMessage()), (int)$e->getCode(), $errorInfo);
+				$message = YII_DEBUG ? 'Failed to prepare SQL: ' . $e->getMessage() : 'Failed to prepare SQL.';
+				throw new Exception($message, (int)$e->getCode(), $errorInfo);
 			}
 		}
 	}
@@ -197,14 +204,15 @@ class Command extends \yii\base\Component
 	public function bindParam($name, &$value, $dataType = null, $length = null, $driverOptions = null)
 	{
 		$this->prepare();
-		if ($dataType === null)
+		if ($dataType === null) {
 			$this->pdoStatement->bindParam($name, $value, $this->connection->getPdoType(gettype($value)));
-		elseif ($length === null)
+		} elseif ($length === null) {
 			$this->pdoStatement->bindParam($name, $value, $dataType);
-		elseif ($driverOptions === null)
+		} elseif ($driverOptions === null) {
 			$this->pdoStatement->bindParam($name, $value, $dataType, $length);
-		else
+		} else {
 			$this->pdoStatement->bindParam($name, $value, $dataType, $length, $driverOptions);
+		}
 		$this->_paramLog[$name] =& $value;
 		return $this;
 	}
@@ -223,10 +231,11 @@ class Command extends \yii\base\Component
 	public function bindValue($name, $value, $dataType = null)
 	{
 		$this->prepare();
-		if ($dataType === null)
+		if ($dataType === null) {
 			$this->pdoStatement->bindValue($name, $value, $this->connection->getPdoType(gettype($value)));
-		else
+		} else {
 			$this->pdoStatement->bindValue($name, $value, $dataType);
+		}
 		$this->_paramLog[$name] = $value;
 		return $this;
 	}
@@ -244,8 +253,7 @@ class Command extends \yii\base\Component
 	public function bindValues($values)
 	{
 		$this->prepare();
-		foreach ($values as $name => $value)
-		{
+		foreach ($values as $name => $value) {
 			$this->pdoStatement->bindValue($name, $value, $this->connection->getPdoType(gettype($value)));
 			$this->_paramLog[$name] = $value;
 		}
@@ -311,7 +319,7 @@ class Command extends \yii\base\Component
 
 	/**
 	 * Executes the SQL statement and returns query result.
-	 * This method is for executing an SQL query that returns result set.
+	 * This method is for executing a SQL query that returns result set.
 	 * @param array $params input parameters (name=>value) for the SQL execution. This is an alternative
 	 * to {@link bindParam} and {@link bindValue}. If you have multiple input parameters, passing
 	 * them in this way can improve the performance. Note that if you pass parameters in this way,

framework/db/dao/Connection.php

@@ -246,7 +246,13 @@ class Connection extends \yii\base\ApplicationComponent
 		'oci' => '\yii\db\dao\oci\Schema',         // Oracle driver
 	);
 
+	/**
+	 * @var Transaction the currently active transaction
+	 */
 	private $_transaction;
+	/**
+	 * @var Schema the database schema
+	 */
 	private $_schema;
 
 	/**
@@ -344,13 +350,9 @@ class Connection extends \yii\base\ApplicationComponent
 				$this->initConnection($this->pdo);
 			}
 			catch (\PDOException $e) {
-				if (YII_DEBUG) {
-					throw new Exception('Failed to open DB connection: ' . $e->getMessage(), (int)$e->getCode(), $e->errorInfo);
-				}
-				else {
-					\Yii::error($e->getMessage(), __CLASS__);
-					throw new Exception('Failed to open DB connection.', (int)$e->getCode(), $e->errorInfo);
-				}
+				\Yii::error("Failed to open DB connection ({$this->dsn}): " . $e->getMessage(), __CLASS__);
+				$message = YII_DEBUG ? 'Failed to open DB connection: ' . $e->getMessage() : 'Failed to open DB connection.';
+				throw new Exception($message, (int)$e->getCode(), $e->errorInfo);
 			}
 		}
 	}
@@ -400,10 +402,8 @@ class Connection extends \yii\base\ApplicationComponent
 		if ($this->emulatePrepare !== null && constant('\PDO::ATTR_EMULATE_PREPARES')) {
 			$this->pdo->setAttribute(\PDO::ATTR_EMULATE_PREPARES, $this->emulatePrepare);
 		}
-		if ($this->charset !== null) {
-			if (in_array($this->getDriverName(), array('pgsql', 'mysql', 'mysqli'))) {
-				$this->pdo->exec('SET NAMES ' . $this->pdo->quote($this->charset));
-			}
+		if ($this->charset !== null && in_array($this->getDriverName(), array('pgsql', 'mysql', 'mysqli'))) {
+			$this->pdo->exec('SET NAMES ' . $this->pdo->quote($this->charset));
 		}
 		if (!empty($this->initSQLs)) {
 			foreach ($this->initSQLs as $sql) {
@@ -434,7 +434,7 @@ class Connection extends \yii\base\ApplicationComponent
 	 */
 	public function getCurrentTransaction()
 	{
-		if ($this->_transaction !== null && $this->_transaction->getActive()) {
+		if ($this->_transaction !== null && $this->_transaction->active) {
 			return $this->_transaction;
 		}
 	}
@@ -459,23 +459,16 @@ class Connection extends \yii\base\ApplicationComponent
 	{
 		if ($this->_schema !== null) {
 			return $this->_schema;
-		}
-		else {
+		} else {
 			$driver = $this->getDriverName();
 			if (isset($this->schemaMap[$driver])) {
 				return $this->_schema = \Yii::create($this->schemaMap[$driver], $this);
-			}
-			else {
+			} else {
 				throw new Exception("Connection does not support reading schema for '$driver' database.");
 			}
 		}
 	}
 
-	public function getQueryBuilder()
-	{
-		return $this->getSchema()->getQueryBuilder();
-	}
-
 	/**
 	 * Returns the query builder for the current DB connection.
 	 * @return QueryBuilder the query builder for the current DB connection.
@@ -513,8 +506,7 @@ class Connection extends \yii\base\ApplicationComponent
 		$this->open();
 		if (($value = $this->pdo->quote($str)) !== false) {
 			return $value;
-		}
-		else {  // the driver doesn't support quote (e.g. oci)
+		} else {  // the driver doesn't support quote (e.g. oci)
 			return "'" . addcslashes(str_replace("'", "''", $str), "\000\n\r\\\032") . "'";
 		}
 	}
@@ -568,8 +560,7 @@ class Connection extends \yii\base\ApplicationComponent
 	{
 		if (($pos = strpos($this->dsn, ':')) !== false) {
 			return strtolower(substr($this->dsn, 0, $pos));
-		}
-		else {
+		} else {
 			return strtolower($this->getAttribute(\PDO::ATTR_DRIVER_NAME));
 		}
 	}

framework/db/dao/DataReader.php

@@ -35,7 +35,7 @@ use yii\db\Exception;
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
  */
-class DataReader extends \yii\base\Component implements \Iterator, \Countable
+class DataReader extends \yii\base\Object implements \Iterator, \Countable
 {
 	private $_statement;
 	private $_closed = false;

framework/db/dao/Expression.php

@@ -26,7 +26,7 @@ namespace yii\db\dao;
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
  */
-class Expression
+class Expression extends \yii\base\Object
 {
 	/**
 	 * @var string the DB expression

framework/db/dao/Query.php

@@ -16,7 +16,7 @@ namespace yii\db\dao;
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
  */
-class Query extends \yii\base\Component
+class Query extends \yii\base\Object
 {
 	/**
 	 * @var mixed the columns being selected. This refers to the SELECT clause in an SQL

framework/db/dao/QueryBuilder.php

@@ -18,7 +18,7 @@ use yii\db\Exception;
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
  */
-class QueryBuilder extends \yii\base\Component
+class QueryBuilder extends \yii\base\Object
 {
 	/**
 	 * @var array the abstract column types mapped to physical column types.

framework/db/dao/Schema.php

@@ -18,7 +18,7 @@ use yii\db\Exception;
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
  */
-abstract class Schema extends \yii\base\Component
+abstract class Schema extends \yii\base\Object
 {
 	public $connection;
 

framework/db/dao/TableSchema.php

@@ -28,7 +28,7 @@ namespace yii\db\dao;
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
  */
-class TableSchema extends \yii\base\Component
+class TableSchema extends \yii\base\Object
 {
 	/**
 	 * @var string name of the schema that this table belongs to.

framework/db/dao/Transaction.php

@@ -36,7 +36,7 @@ use yii\db\Exception;
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
  */
-class Transaction extends \yii\base\Component
+class Transaction extends \yii\base\Object
 {
 	/**
 	 * @var boolean whether this transaction is active. Only an active transaction
@@ -67,7 +67,7 @@ class Transaction extends \yii\base\Component
 	public function commit()
 	{
 		if ($this->active && $this->connection->getActive()) {
-			Yii::trace('Committing transaction', __CLASS__);
+			\Yii::trace('Committing transaction', __CLASS__);
 			$this->connection->pdo->commit();
 			$this->active = false;
 		}
@@ -83,7 +83,7 @@ class Transaction extends \yii\base\Component
 	public function rollback()
 	{
 		if ($this->active && $this->connection->getActive()) {
-			Yii::trace('Rolling back transaction', __CLASS__);
+			\Yii::trace('Rolling back transaction', __CLASS__);
 			$this->connection->pdo->rollBack();
 			$this->active = false;
 		}