Generating Token Id in mysql

hello, I have a table named ChangePasswordRequest in which i have fields like id(bigint,not null), UserId(bigint,null), Token(uniqueidentifier,null),RequestDate(datetime,null) and TokenStatus(varchar(10)).
I have a webform named ForgotPassword.aspx, when user clicks on forgot password on the Login page, this page opens. Now I want when user enters his email-id and clicks on send button, a token must be generated in the table which is unique and the token status must be open. As of now I am being able to send an email to the email-id for redirecting to page PasswordReset.aspx where the user can change his password. After changing the password the TokenStatus in the table should be closed.
Pls help me how to use and insert data into the Table on button click of pages ForgotPassword.aspx and PasswordReset.aspx...