Problem solve Get help with specific problems with your technologies, process and projects.

Using hash tables for fast lookup

If you have an internal table in a program used solely for lookup, it's good programming practice to use a hash table.

If you have an internal table in your program which is used solely for lookup, it is good programming practice...

to use a hash table. The example below shows this, in combination with a method for buffering SELECT SINGLE results.


*&      Form  select_dispo
*       Get MRP controller and in-house production time from material 
*       and plant
*      --> MATNR  Material
*      --> RESWK  Plant
*      <-- DISPO  MRP controller
*      <-- DZEIT  In-house production time
form select_from_marc using matnr werks dispo dzeit.

  types: begin of mrp_lookup_type,
           matnr like marc-matnr,
           werks like marc-werks,
           dispo like marc-dispo,
           dzeit like marc-dzeit,
         end of mrp_lookup_type.

* Define static hashed table to hold results
  statics: st_mrp type hashed table of mrp_lookup_type
                  with unique key matnr werks.

  data: l_wa_mrp type mrp_lookup_type.

  clear dzeit.

* See if data is in the table
  read table st_mrp into l_wa_mrp with table key matnr = matnr
                                                 werks = werks.

* If not in table, get it from the database
  if not sy-subrc is initial.

    select single dispo dzeit from marc
        into corresponding fields of l_wa_mrp-dispo
        where matnr eq matnr
          and werks eq werks.

* Insert into table
    l_wa_mrp-matnr = matnr.
    l_wa_mrp-werks = werks.
    insert l_wa_mrp into table st_mrp.

  dispo = l_wa_mrp-dispo.                      " MRP Controller
  dzeit = l_wa_mrp-dzeit.                      " Inhouse production time
endform.                    " select_from_marc
This was last published in June 2001

Dig Deeper on SAP ABAP

Start the conversation

Send me notifications when other members comment.

By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Please create a username to comment.