diff --git a/docs/guide/extensions.md b/docs/guide/extensions.md
index 4f178ef..de7c9fa 100644
--- a/docs/guide/extensions.md
+++ b/docs/guide/extensions.md
@@ -17,9 +17,11 @@ using the following syntax: e.g. `[[name()]]`, `[[name\space\MyClass::name()]]`.
 ### Namespace and package names
 
 - Extension MUST use the type `yii2-extension` in `composer.json` file.
-- Extension MUST NOT use `yii` or `yii2` in the composer package name or in the namespaces used in the package.
+- Extension MUST NOT use `yiisoft` in the composer package name, the composer vendor name or in the namespaces used in the package.
+- Additionally extensions MUST NOT use `yii` or `yii2` in their composer vendor name.
+- Extension MUST NOT have a root-namespace named `\yii`, `\yii2` or `\yiisoft`.
 - Extension SHOULD use namespaces in this format `vendor-name\package` (all lowercase).
-- Extension MAY use a `yii2-` prefix in the composer vendor name (URL).
+- Extension MAY use `yii2-` in the composer package name (e.g `vendor\yii2-api-adapter` or `vendor\my-yii2-package` (URL).
 - Extension MAY use a `yii2-` prefix in the repository name (URL).
 
 ### Dependencies
@@ -75,4 +77,4 @@ Authorization
 Testing your extension
 ----------------------
 
-- Extension SHOULD be testable with *PHPUnit*.
\ No newline at end of file
+- Extension SHOULD be testable with *PHPUnit*.
diff --git a/docs/internals/git-workflow.md b/docs/internals/git-workflow.md
index 3386df6..fc8b275 100644
--- a/docs/internals/git-workflow.md
+++ b/docs/internals/git-workflow.md
@@ -18,10 +18,10 @@ then you must [setup your GIT installation to work with GitHub](http://help.gith
 
 ### 2. Add the main Yii repository as an additional git remote called "upstream"
 
-Change to the directory where you cloned Yii, normally, "yii". Then enter the following command:
+Change to the directory where you cloned Yii, normally, "yii2". Then enter the following command:
 
 ```
-git remote add upstream git://github.com/yiisoft/yii.git
+git remote add upstream git://github.com/yiisoft/yii2.git
 ```
 
 ### 3. Make sure there is an issue created for the thing you are working on.
diff --git a/extensions/yii/sphinx/Command.php b/extensions/yii/sphinx/Command.php
index ba802f5..9197b67 100644
--- a/extensions/yii/sphinx/Command.php
+++ b/extensions/yii/sphinx/Command.php
@@ -319,7 +319,7 @@ class Command extends \yii\db\Command
 	/**
 	 * @inheritdoc
 	 */
-	public function checkIntegrity($check = true, $schema = '')
+	public function checkIntegrity($check = true, $schema = '', $table = '')
 	{
 		throw new NotSupportedException('"' . __METHOD__ . '" is not supported.');
 	}
diff --git a/framework/CHANGELOG.md b/framework/CHANGELOG.md
index 747e59d..b7699ac 100644
--- a/framework/CHANGELOG.md
+++ b/framework/CHANGELOG.md
@@ -34,6 +34,8 @@ Yii Framework 2 Change Log
 - Enh #1611: Added `BaseActiveRecord::markAttributeDirty()` (qiangxue)
 - Enh #1634: Use masked CSRF tokens to prevent BREACH exploits (qiangxue)
 - Enh #1641: Added `BaseActiveRecord::updateAttributes()` (qiangxue)
+- Enh #1646: Added postgresql `QueryBuilder::checkIntegrity` and `QueryBuilder::resetSequence` (Ragazzo)
+- Enh #1645: Added `Connection::$pdoClass` property (Ragazzo)
 - Enh: Added `favicon.ico` and `robots.txt` to defauly application templates (samdark)
 - Enh: Added `Widget::autoIdPrefix` to support prefixing automatically generated widget IDs (qiangxue)
 - Enh: Support for file aliases in console command 'message' (omnilight)
diff --git a/framework/yii/db/ActiveQueryTrait.php b/framework/yii/db/ActiveQueryTrait.php
index c8ba773..79bac78 100644
--- a/framework/yii/db/ActiveQueryTrait.php
+++ b/framework/yii/db/ActiveQueryTrait.php
@@ -6,6 +6,7 @@
  */
 
 namespace yii\db;
+use yii\base\InvalidCallException;
 
 /**
  * ActiveQueryTrait implements the common methods and properties for active record query classes.
@@ -42,6 +43,10 @@ trait ActiveQueryTrait
 	public function __call($name, $params)
 	{
 		if (method_exists($this->modelClass, $name)) {
+			$method = new \ReflectionMethod($this->modelClass, $name);
+			if (!$method->isStatic() || !$method->isPublic()) {
+				throw new InvalidCallException("The scope method \"{$this->modelClass}::$name()\" must be public and static.");
+			}
 			array_unshift($params, $this);
 			call_user_func_array([$this->modelClass, $name], $params);
 			return $this;
diff --git a/framework/yii/db/Command.php b/framework/yii/db/Command.php
index 2075b2d..76b4269 100644
--- a/framework/yii/db/Command.php
+++ b/framework/yii/db/Command.php
@@ -743,12 +743,13 @@ class Command extends \yii\base\Component
 	 * @param boolean $check whether to turn on or off the integrity check.
 	 * @param string $schema the schema name of the tables. Defaults to empty string, meaning the current
 	 * or default schema.
+	 * @param string $table the table name.
 	 * @return Command the command object itself
 	 * @throws NotSupportedException if this is not supported by the underlying DBMS
 	 */
-	public function checkIntegrity($check = true, $schema = '')
+	public function checkIntegrity($check = true, $schema = '', $table = '')
 	{
-		$sql = $this->db->getQueryBuilder()->checkIntegrity($check, $schema);
+		$sql = $this->db->getQueryBuilder()->checkIntegrity($check, $schema, $table);
 		return $this->setSql($sql);
 	}
 }
diff --git a/framework/yii/db/Connection.php b/framework/yii/db/Connection.php
index ef5be87..030e6c7 100644
--- a/framework/yii/db/Connection.php
+++ b/framework/yii/db/Connection.php
@@ -253,7 +253,10 @@ class Connection extends Component
 	 * @var Schema the database schema
 	 */
 	private $_schema;
-
+	/**
+     * @var string Custom PDO wrapper class. If not set, it will use "PDO" or "yii\db\mssql\PDO" when MSSQL is used.
+	 */
+	public $pdoClass;
 
 	/**
 	 * Returns a value indicating whether the DB connection is established.
@@ -338,13 +341,17 @@ class Connection extends Component
 	 */
 	protected function createPdoInstance()
 	{
-		$pdoClass = 'PDO';
-		if (($pos = strpos($this->dsn, ':')) !== false) {
-			$driver = strtolower(substr($this->dsn, 0, $pos));
-			if ($driver === 'mssql' || $driver === 'dblib' || $driver === 'sqlsrv') {
-				$pdoClass = 'yii\db\mssql\PDO';
+		$pdoClass = $this->pdoClass;
+		if ($pdoClass === null) {
+			$pdoClass = 'PDO';
+			if (($pos = strpos($this->dsn, ':')) !== false) {
+				$driver = strtolower(substr($this->dsn, 0, $pos));
+				if ($driver === 'mssql' || $driver === 'dblib' || $driver === 'sqlsrv') {
+					$pdoClass = 'yii\db\mssql\PDO';
+				}
 			}
 		}
+
 		return new $pdoClass($this->dsn, $this->username, $this->password, $this->attributes);
 	}
 
diff --git a/framework/yii/db/mysql/Schema.php b/framework/yii/db/mysql/Schema.php
index a649d8a..d5258c1 100644
--- a/framework/yii/db/mysql/Schema.php
+++ b/framework/yii/db/mysql/Schema.php
@@ -280,7 +280,7 @@ class Schema extends \yii\db\Schema
 	 * @param string $schema the schema of the tables. Defaults to empty string, meaning the current or default schema.
 	 * @return array all table names in the database. The names have NO schema name prefix.
 	 */
-	protected function findTableNames($schema = '')
+	public function findTableNames($schema = '')
 	{
 		$sql = 'SHOW TABLES';
 		if ($schema !== '') {
diff --git a/framework/yii/db/pgsql/QueryBuilder.php b/framework/yii/db/pgsql/QueryBuilder.php
index 09a620d..f1ac032 100644
--- a/framework/yii/db/pgsql/QueryBuilder.php
+++ b/framework/yii/db/pgsql/QueryBuilder.php
@@ -8,6 +8,8 @@
 
 namespace yii\db\pgsql;
 
+use yii\base\InvalidParamException;
+
 /**
  * QueryBuilder is the query builder for PostgreSQL databases.
  *
@@ -62,6 +64,65 @@ class QueryBuilder extends \yii\db\QueryBuilder
 	}
 
 	/**
+	 * Creates a SQL statement for resetting the sequence value of a table's primary key.
+	 * The sequence will be reset such that the primary key of the next new row inserted
+	 * will have the specified value or 1.
+	 * @param string $tableName the name of the table whose primary key sequence will be reset
+	 * @param mixed $value the value for the primary key of the next new row inserted. If this is not set,
+	 * the next new row's primary key will have a value 1.
+	 * @return string the SQL statement for resetting sequence
+	 * @throws InvalidParamException if the table does not exist or there is no sequence associated with the table.
+	 */
+	public function resetSequence($tableName, $value = null)
+	{
+		$table = $this->db->getTableSchema($tableName);
+		if ($table !== null && $table->sequenceName !== null) {
+			$sequence = '"' . $table->sequenceName . '"';
+
+			if (strpos($sequence, '.') !== false) {
+				$sequence = str_replace('.', '"."', $sequence);
+			}
+
+			$tableName = $this->db->quoteTableName($tableName);
+			if ($value === null) {
+				$key = reset($table->primaryKey);
+				$value = "(SELECT COALESCE(MAX(\"{$key}\"),0) FROM {$tableName})+1";
+			} else {
+				$value = (int)$value;
+			}
+			return "SELECT SETVAL('$sequence',$value,false)";
+		} elseif ($table === null) {
+			throw new InvalidParamException("Table not found: $tableName");
+		} else {
+			throw new InvalidParamException("There is not sequence associated with table '$tableName'.");
+		}
+	}
+
+	/**
+	 * Builds a SQL statement for enabling or disabling integrity check.
+	 * @param boolean $check whether to turn on or off the integrity check.
+	 * @param string $schema the schema of the tables.
+	 * @param string $table the table name.
+	 * @return string the SQL statement for checking integrity
+	 */
+	public function checkIntegrity($check = true, $schema = '', $table = '')
+	{
+		$enable = $check ? 'ENABLE' : 'DISABLE';
+		$schema = $schema ? $schema : $this->db->schema->defaultSchema;
+		$tableNames = $table ? [$table] : $this->db->schema->findTableNames($schema);
+		$command = '';
+
+		foreach ($tableNames as $tableName) {
+			$tableName = '"' . $schema . '"."' . $tableName . '"';
+			$command .= "ALTER TABLE $tableName $enable TRIGGER ALL; ";
+		}
+
+		#enable to have ability to alter several tables
+		$this->db->pdo->setAttribute(\PDO::ATTR_EMULATE_PREPARES, true);
+		return $command;
+	}
+
+	/**
 	 * Builds a SQL statement for changing the definition of a column.
 	 * @param string $table the table whose column is to be changed. The table name will be properly quoted by the method.
 	 * @param string $column the name of the column to be changed. The name will be properly quoted by the method.
diff --git a/framework/yii/db/pgsql/Schema.php b/framework/yii/db/pgsql/Schema.php
index 96889ab..59340c9 100644
--- a/framework/yii/db/pgsql/Schema.php
+++ b/framework/yii/db/pgsql/Schema.php
@@ -158,7 +158,7 @@ class Schema extends \yii\db\Schema
 	 * @param string $schema the schema of the tables. Defaults to empty string, meaning the current or default schema.
 	 * @return array all table names in the database. The names have NO schema name prefix.
 	 */
-	protected function findTableNames($schema = '')
+	public function findTableNames($schema = '')
 	{
 		if ($schema === '') {
 			$schema = $this->defaultSchema;
diff --git a/framework/yii/db/sqlite/Schema.php b/framework/yii/db/sqlite/Schema.php
index 9f410b4..6548999 100644
--- a/framework/yii/db/sqlite/Schema.php
+++ b/framework/yii/db/sqlite/Schema.php
@@ -87,7 +87,7 @@ class Schema extends \yii\db\Schema
 	 * If not empty, the returned table names will be prefixed with the schema name.
 	 * @return array all table names in the database.
 	 */
-	protected function findTableNames($schema = '')
+	public function findTableNames($schema = '')
 	{
 		$sql = "SELECT DISTINCT tbl_name FROM sqlite_master WHERE tbl_name<>'sqlite_sequence'";
 		return $this->db->createCommand($sql)->queryColumn();
diff --git a/framework/yii/test/DbFixtureManager.php b/framework/yii/test/DbFixtureManager.php
index d78d28f..f657a40 100644
--- a/framework/yii/test/DbFixtureManager.php
+++ b/framework/yii/test/DbFixtureManager.php
@@ -146,6 +146,7 @@ class DbFixtureManager extends Component
 		}
 
 		$this->db->createCommand()->truncateTable($tableName)->execute();
+		$this->db->createCommand()->resetSequence($tableName,1)->execute();
 
 		$fileName = $this->basePath . '/' . $tableName . '.php';
 		if (!is_file($fileName)) {
diff --git a/framework/yii/web/Request.php b/framework/yii/web/Request.php
index aae2e3c..ee232f4 100644
--- a/framework/yii/web/Request.php
+++ b/framework/yii/web/Request.php
@@ -1039,7 +1039,8 @@ class Request extends \yii\base\Request
 		if ($this->_maskedCsrfToken === null) {
 			$token = $this->getCsrfToken();
 			$mask = Security::generateRandomKey(self::CSRF_MASK_LENGTH);
-			$this->_maskedCsrfToken = base64_encode($mask . $this->xorTokens($token, $mask));
+			// The + sign may be decoded as blank space later, which will fail the validation
+			$this->_maskedCsrfToken = str_replace('+', '.', base64_encode($mask . $this->xorTokens($token, $mask)));
 		}
 		return $this->_maskedCsrfToken;
 	}
@@ -1120,7 +1121,7 @@ class Request extends \yii\base\Request
 
 	private function validateCsrfTokenInternal($token, $trueToken)
 	{
-		$token = base64_decode($token);
+		$token = str_replace('.', '+', base64_decode($token));
 		$n = StringHelper::byteLength($token);
 		if ($n <= self::CSRF_MASK_LENGTH) {
 			return false;