Add not null

[Ather Rehan]

I have problem at time of altering the table to not null.
the syntax I am using is

ALTER TABLE table_name MODIFY column_name NOT NULL

the error is
Msg 102, Level 15, State 1, Line 1
Incorrect syntax near 'MODIFY'.

[Dody]

to modify column structure user Alter column not modify

try this line

ALTER TABLE table_name 
Alter column column_name column_type NOT NULL