Changing Matchcodes 
Procedure
You can display the matchcode maintenance screen from the initial screen of the ABAP Dictionary. Choose Utilities ®
Further Dictionary objects.
A dialog box appears.
Select the object type Matchcode object and enter a four-place name. Choose Change.Here you can:
change the matchcode objects
change the matchcode IDs
convert to transparent matchcodes
determine the effect of conversion on transparent matchcodes
deactivate the matchcode IDs
delete the matchcode objects
delete the matchcode IDs