SQL Error in WHERE clause [closed]

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Closed 8 years ago.

I have the tables

Department: id, name
Employee: id, departmentId, name, surname

departmentId is a foreign key referencing Department(id) The Query:

SELECT * FROM Employee WHERE Employee.departmentId = Department.id;

returns the error "Unknown column Department.id in where clause"

I can't place this error. How do i fix this?

Thanks

Answer 1

You need to actually include the department table

SELECT * 
FROM Employee 
JOIN Department
   ON Employee.departmentId = Department.id;

This uses explicit JOIN syntax which is ANSI standard. You should refrain from implicit joins.

Answer 2

That's because your Department table is not in your FROM clause. Include it.

select *
from Employee, Department
where Employee.departmentId = Department.id

Answer 3

You aren't including Department in your from clause....

SELECT * FROM Employee, Department WHERE Employee.departmentId = Department.id;