查询重复结果几次

Question

因此，基本上，我是SQL和查询的新手，我希望所有拥有蓝色徽章的员工。

这是我的尝试：

SELECT   Employee.Employee_ID,
         Car_Registration,
         Badge.Badge_Colour,
         Start_Time,
         End_Time,
         Date_Issued,
         Booking_ID 
FROM     Employee,
         Vehicle,
         Badge,
         Booking 
WHERE    Employee.Employee_ID = Booking.Employee_ID 
AND      Badge.Badge_Colour = Employee.Badge_Colour 
AND      Badge.Badge_Colour = 'Blue'

有人可以识别我的查询问题吗？