多個INNER JOIN SQL訪問語法

Question

我想通過INNER JOIN和table(users)從table(six_attendance, five_attendance)中獲取數據。這是我曾嘗試：

$query = mysql_query("SELECT * 
FROM 
(users 
INNER JOIN six_attendance 
ON users.username = six_attendance.username) 
INNER JOIN five_attendance 
ON users.username = five_attendance.username 
WHERE six_attendance.username OR five_attendance.username ='$reg_no'"); 

Answer 1

$query = mysql_query("SELECT * 
FROM 
users 
INNER JOIN six_attendance 
ON users.username = six_attendance.username 
INNER JOIN five_attendance 
ON users.username = five_attendance.username 
WHERE six_attendance.username='$reg_no' OR five_attendance.username ='$reg_no'");