fix declare checker variable

db/StoredProcedures.sql

@@ -4030,6 +4030,7 @@ CREATE FUNCTION `GetUserFullNameByAccountID`	( 	`AccountID` INT(11)
 NO SQL
 BEGIN
 	DECLARE UserFullName VARCHAR(255);
+	DECLARE checker INT;
 
 	SET checker = -1;
 	SELECT students.ID As ID, CONCAT(students.LastName, students.FirstName, students.SecondName) As UserName