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..b3c13e5 100644
--- a/framework/CHANGELOG.md
+++ b/framework/CHANGELOG.md
@@ -34,6 +34,7 @@ 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: 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/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/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..47255e6 100644
--- a/framework/yii/db/pgsql/QueryBuilder.php
+++ b/framework/yii/db/pgsql/QueryBuilder.php
@@ -7,6 +7,7 @@
  */
 
 namespace yii\db\pgsql;
+use yii\base\InvalidParamException;
 
 /**
  * QueryBuilder is the query builder for PostgreSQL databases.
@@ -62,6 +63,66 @@ 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();