Alter Table Modify Not Null

[neelam dadhwal]

My table (employee) has this description 
Field       Type        Null  Key  Default Extra
Emp_id      int(4)      NO    PRI  Null
Emp_name    varchar(20) YES        Null
Mgr_id      int(4)      YES        Null
Hire_date   date        YES        Null
Salary      int(5)      YES        Null
Commission  int(4)      YES        Null
Dept_id     int(3)      YES        Null                     

I ran this query 
alter table employee modify Emp_name not null;

but returns the error
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'Emp_name not null' at line 1

There are no null values in this field. 

Any reasons.

[pritaeas]

You need to specify the whole column, including it's type:

ALTER TABLE employee MODIFY Emp_name varchar(20) NOT NULL;