diff --git a/system/database/DB_driver.php b/system/database/DB_driver.php
index ba6a4b7..4791c3b 100644
--- a/system/database/DB_driver.php
+++ b/system/database/DB_driver.php
@@ -1421,7 +1421,7 @@
 	 */
 	protected function _has_operator($str)
 	{
-		return (bool) preg_match('/(<|>|!|=|\sIS NULL|\sIS NOT NULL|\sEXISTS|\sNOT EXISTS|\sBETWEEN|\sLIKE|\sIN\s*\(|\s)/i', trim($str));
+		return (bool) preg_match('/(<|>|!|=|\sIS NULL|\sIS NOT NULL|\sEXISTS|\sBETWEEN|\sLIKE|\sIN\s*\(|\s)/i', trim($str));
 	}
 
 	// --------------------------------------------------------------------
@@ -1446,9 +1446,9 @@
 				'\s*<>?\s*',			// <, <>
 				'\s*>\s*',			// >
 				'\s+IS NULL',			// IS NULL
-				'\s+IS NOT NULL',	// IS NOT NULL
+				'\s+IS NOT NULL',		// IS NOT NULL
 				'\s+EXISTS\s*\([^\)]+\)',	// EXISTS(sql)
-				'\s+NOT EXISTS\s*\([^\)]+\)',		// NOT EXISTS(sql)
+				'\s+NOT EXISTS\s*\([^\)]+\)',	// NOT EXISTS(sql)
 				'\s+BETWEEN\s+\S+\s+AND\s+\S+',	// BETWEEN value AND value
 				'\s+IN\s*\([^\)]+\)',		// IN(list)
 				'\s+NOT IN\s*\([^\)]+\)',	// NOT IN (list)
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index 3dc7ade..54583e6 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -137,7 +137,6 @@
 
 -  Database
 
-   -  Added EXISTS / NOT EXISTS support to DB_Driver class.
    -  Added **dsn** configuration setting for drivers that support DSN strings (PDO, PostgreSQL, Oracle, ODBC, CUBRID).
    -  Added **schema** configuration setting (defaults to *public*) for drivers that might need it (currently used by PostgreSQL and ODBC).
    -  Added subdrivers support (currently only used by PDO).
@@ -166,6 +165,7 @@
       - Added an optional parameter that allows to disable escaping (useful for custom fields) for methods ``join()``, ``order_by()``, ``where_in()``, ``or_where_in()``, ``where_not_in()``, ``or_where_not_in()``, ``insert()``, ``insert_batch()``.
       - Added support for ``join()`` with multiple conditions.
       - Added support for *USING* in ``join()``.
+      - Added support for *EXISTS* in ``where()``.
       - Added seed values support for random ordering with ``order_by(seed, 'RANDOM')``.
       - Changed ``limit()`` to ignore NULL values instead of always casting to integer.
       - Changed ``offset()`` to ignore empty values instead of always casting to integer.