DTP routine to find timestamp range

Question

I am working on a DTP filter routine for a timestamp field in the format of YYYYMMDDhhmmss. I am trying to declare the range as ({timestamp 3 months ago} to {current timestamp}). I am very new to ABAP and basically have the code set up right now so it doesn't have any syntax errors. I am currently having trouble getting the correct timestamp to be filled when I assign it to "l_ts".

*$*$ begin of routine - insert your code only below this line        *-*
BREAK-POINT.


DATA: l_idx LIKE sy-tabix,
        l_ts TYPE rstimestmp,
        l_ts2 TYPE rstimestmp.


  READ TABLE l_t_range WITH KEY
   fieldname = 'TIMESTAMP'.
   l_idx = sy-tabix.

* Capture the Current Date
  l_ts = sy-datlo + sy-timlo.
  l_ts2 = ( sy-datlo + sy-timlo ) - 93.

  IF l_idx <> 0.

* fill the Selection table.
    l_t_range-low = l_ts.
    l_t_range-sign = 'I'.
    l_t_range-option = 'BT'.
    l_t_range-high = l_ts2.

    MODIFY l_t_range INDEX l_idx.
 ELSE.
* fill the Selection table.
    l_t_range-fieldname = 'TIMESTAMP'.
    l_t_range-low = l_ts.
    l_t_range-high = l_ts2.
    l_t_range-sign = 'I'.
    l_t_range-option = 'BT'.


    APPEND l_t_range.
  ENDIF.

  p_subrc = 0.


*$*$ end of routine - insert your code only before this line         *-* 

Answer 1

You're mixing up timestamps and discrete date and time calculations - won't work this way. What you'll really want is probably something like this:

  DATA: l_date TYPE d,
        l_time TYPE t,
        l_ts   TYPE rstimestmp.

  FIELD-SYMBOLS: <ls_param> LIKE LINE OF l_t_range.

* ensure that the parameter exists
  READ TABLE l_t_range ASSIGNING <ls_param> WITH KEY fieldname = 'TIMESTAMP'.
  IF sy-subrc <> 0.
    APPEND INITIAL LINE TO l_t_range ASSIGNING <ls_param>.
    <ls_param>-fieldname = 'TIMESTAMP'.
  ENDIF.

  <ls_param>-sign = 'I'.
  <ls_param>-option = 'BT'.

* "from" date = three months ago, more or less - probably the start of the day?
  l_date = sy-datlo - 93.
  l_time = '000000'. " or sy-timlo.
  CONVERT DATE l_date TIME l_time INTO TIME STAMP l_ts TIME ZONE sy-zonlo. 
  <ls_param>-low = l_ts.

* "to" date = today - probably the end of the day?
  l_date = sy-datlo.
  l_time = '235959'. " or sy-timlo.
  CONVERT DATE l_date TIME l_time INTO TIME STAMP l_ts TIME ZONE sy-zonlo. 
  <ls_param>-high = l_ts.