Fist login to SAP and goto SE16
Enter table name and execute.
Now enter /h in transaction box and press enter. it will say debug is switched on.
then double click on the entry, it will open a new window in debug mode:
Now click on F7(Return) , it will directly take to below screen(if code = 'SHOW'
double click on code, it will display value right side.
Change te vlaue to EDIT
Once changed the valued, press enter.
Click on Continue button
It will take you back to SE16 in Editable mode.
Once you enter or modify the value, click on save. It wll give message: Database record created successfully.