diff --git a/common/framework/parsers/dbquery/variablebase.php b/common/framework/parsers/dbquery/variablebase.php
index 72367f428..3ae58f96a 100644
--- a/common/framework/parsers/dbquery/variablebase.php
+++ b/common/framework/parsers/dbquery/variablebase.php
@@ -105,12 +105,12 @@ class VariableBase
 		switch ($this->operation)
 		{
 			case 'equal':
-				$where = sprintf('%s %s %s', $column, ($is_expression && $value === 'NULL') ? 'IS' : '=', $is_expression ? $value : '?');
+				$where = sprintf('%s = %s', $column, $is_expression ? $value : '?');
 				if (!$is_expression) $params[] = $value;
 				break;
 			case 'notequal':
 			case 'not_equal':
-				$where = sprintf('%s %s %s', $column, ($is_expression && $value === 'NULL') ? 'IS NOT' : '!=', $is_expression ? $value : '?');
+				$where = sprintf('%s != %s', $column, $is_expression ? $value : '?');
 				if (!$is_expression) $params[] = $value;
 				break;
 			case 'more':
diff --git a/tests/unit/framework/parsers/DBQueryParserTest.php b/tests/unit/framework/parsers/DBQueryParserTest.php
index cf99819ed..85278c078 100644
--- a/tests/unit/framework/parsers/DBQueryParserTest.php
+++ b/tests/unit/framework/parsers/DBQueryParserTest.php
@@ -423,7 +423,7 @@ class DBQueryParserTest extends \Codeception\TestCase\Test
 		$sql = $query->getQueryString('rx_', $args);
 		$params = $query->getQueryParams();
 		
-		$this->assertEquals('UPDATE `rx_documents` SET `member_srl` = ?, `nick_name` IS NULL, `voted_count` = `voted_count` + ? WHERE `document_srl` = ?', $sql);
+		$this->assertEquals('UPDATE `rx_documents` SET `member_srl` = ?, `nick_name` = NULL, `voted_count` = `voted_count` + ? WHERE `document_srl` = ?', $sql);
 		$this->assertEquals(['456', '5', '123'], $params);
 	}