diff --git a/system/database/DB_driver.php b/system/database/DB_driver.php
index 425657e..53decf0 100644
--- a/system/database/DB_driver.php
+++ b/system/database/DB_driver.php
@@ -1375,7 +1375,9 @@
 			$fields[$this->protect_identifiers($key)] = $this->escape($val);
 		}
 
-		return $this->_update($this->protect_identifiers($table, TRUE, NULL, FALSE), $fields);
+		$sql = $this->_update($this->protect_identifiers($table, TRUE, NULL, FALSE), $fields);
+		$this->_reset_write();
+		return $sql;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/DB_query_builder.php b/system/database/DB_query_builder.php
index 292621b..355613c 100644
--- a/system/database/DB_query_builder.php
+++ b/system/database/DB_query_builder.php
@@ -1846,6 +1846,7 @@
 		{
 			$this->query($this->_update_batch($this->protect_identifiers($table, TRUE, NULL, FALSE), array_slice($this->qb_set, $i, 100), $this->protect_identifiers($index)));
 			$affected_rows += $this->affected_rows();
+			$this->qb_where = array();
 		}
 
 		$this->_reset_write();