In ALV Reports,the output is displayed by using the function
module:
 REUSE_ALV_GRID_DISPLAY or REUSE_ALV_LIST_DISPLAY
 Input for the above function modules is 
  program name and fieldcatalog and data internal table.

You can edit the records in the ouput list by using EDIT =
'X' option in the field catalog.

while filling the field catalog we have to consider the
field EDIT = 'X'.

But this is used for print purpose only we cannot save into
database.

above answer is right

It is possible to save in the database also by using OO ALV 
by using event DATA_CHANGED and method CHECK_CHANGED_DATA  
from class CL_GUI_ALV_GRID.


Buddula15

Hi 
We can edit by using field catalog Edit as X.And in
selection screen you can edit that value and to update the
database you can use the statement like move the valu to a
temp table.then edit the database from that temp table.