SQL Code error

[Five]

I am using this tutorial to make a hotel

You must be registered for see links

And It told me to enter this sql code:

ALTER TABLE `users` ADD `seckey` VARCHAR( 999 ) NOT NULL

When I entered it I got this error
#1064 - 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 '​' at line 1

Anyone know how to fix it?

 

[Jerry]

Before:

ALTER TABLE `users` ADD `seckey` VARCHAR( 999 ) NOT NULL

After:

ALTER TABLE `users` ADD `seckey` VARCHAR( 999 ) NOT NULL;