Regarding method used in alv

Question

hi,
i am new to this forum,can anybody tell mme which method is more efficient in ALV REPORT:-
1.)  DECLARING TYPES AND WORK AREAS
                 OR
2.)  DECLARING INTERNAL TABLE AND PASSING IT IN FUNCTIONS.
PLZZZ ANY BODY GIVE EXAMPLE OF 2 ND OPTION AS I  HAD MADE REPORT  BUT D OUTLOOK SEEMS TO BE OUTDATED AS COMPARE TO 1ST METHOD.

Answer 1

Hello and Welcome,
As far as i have worked...there is no such categorisation as using
1.) DECLARING TYPES AND WORK AREAS
OR
2.) DECLARING INTERNAL TABLE AND PASSING IT IN FUNCTIONS.
Each has there own set of plus and minus points..we do a mix of all the above to suit the requirements given..sort of (1) AND (2)
eg:
Declaring types:The main advantage is that unless you do a 'data' initialisation no memory is used and you can create multiple objects of the same structure if we are using types..so in short with types we can also create a work area as well as an internal table
Types : Begin of demo_types,
            date type sy-datum,
            screen type sy-dynnr,
           end of demo_types.
data : Internal_table1 type table of demo_types with header line.
data : Internal_table2 type table of demo_types.
data : work_area     type demo_types.
we can declare internal table with header line if the choice is not to use a separate work area for instance while looping which can be done as
loop at internal table ....endloop...."with headerline
loop at internal table into workarea...endloop...."without/with header line
<u><i><b>so ---> if you have large data with complex calculations we need all of what you have mentioned in points 1 and 2....If there is a specifIC doubt ..please revert back..and reward if helpful..to encourage more healthy answers to the query
the query is very general and the more and more you work on a report...the choice will come naturally...just in case you need more examples in ALV please refer the following programs(go to se38 -> BCALV* -> F4 --> you have list of ALV programs</b></i></u>
]BCALV_EDIT_01        Switch on and off the ready-for-input status of the entire grid
BCALV_EDIT_02                  Define ready-for-input status at cell level
BCALV_EDIT_03                  Verification of modified cells
BCALV_EDIT_04                  Delete and append rows
BCALV_EDIT_05                  Checkboxes
BCALV_EDIT_06                  Dropdown Listbox at Column Level
BCALV_EDIT_07                  Dropdown Listbox at Cell Level
BCALV_EDIT_08                  Integrate Non-Standard F4 Help
BCALV_GRID_01                  Processing Print Events
BCALV_GRID_02                  Display Detail List in Dialog Box Container
BCALV_GRID_03                  Detail List in Dialog Window
BCALV_GRID_04                  Display Exceptions (LEDs or Traffic Lights)
BCALV_GRID_05                  Add a Self-Defined Button to the Toolbar
BCALV_GRID_06                  Define Self-Defined Context Menu
BCALV_GRID_07                  Define a Menu in the Toolbar
BCALV_GRID_08                  Define a Menu with Default Pushbutton
BCALV_GRID_09                  Saving Options for Layouts
BCALV_GRID_10                  Load a layout before list display
BCALV_GRID_11                  Test for new layout function modules
Regards
Byju