The Table Maintenance Generator (TMG) is a tool used to edit or create or delete the contents of a database table. The table maintenance screen is opened in change mode by default but we can also open it in display mode by default by doing certain settings.
Goto T-code SE93 ->Select Trans with parameter option (Parameter Transaction) -> Specify Transaction SM30
(In SM30, we find display, Maintain options. We can view the table contents by choosing Display and we can create table entries by choosing Maintain.)
Check on Skip first screen button
Go down and on Default value secton
SHOW = 'X'
Now your table maint screen will be in Display mode by default .