diff --git a/db/StoredProcedures.sql b/db/StoredProcedures.sql
index aff29e6b9edb9121a26d07e310112db8e2f11c81..a859200b7f57bf60b6a8c02ecd3b3b0573565331 100644
--- a/db/StoredProcedures.sql
+++ b/db/StoredProcedures.sql
@@ -1014,7 +1014,7 @@ BEGIN
 		LEFT JOIN 	`disciplines_students`		ON 	DisciplineID = disciplines_students.DisciplineID AND
 													students.ID = disciplines_students.StudentID
 		WHERE 	disciplines_students.Type = 'attach'	OR
-				(	disciplines_students.Type != 'detach' AND 
+				(	( disciplines_students.Type IS NULL OR disciplines_students.Type != 'detach' ) AND 
 					disciplines_groups.StudyGroupID IS NOT NULL 
 				);
 	ELSE