Question for "FOR ALL ENTRIES"

Question

Some materials mentioned that If the table on which the For All Entries IN clause is based is very large, the performance will go down instead of improving. But what's the moderate size of the table used in "FOR ALL ENTRIES"?

Answer 1

Hi Dan,
Yes the material you read is correct some ways.
For all entries can be created using this addition to the where clause in a select statement. It speeds up the performance tremendously, but the cons of using this variation are listed below
Duplicates are automatically removed from the resulting data set. Hence care should be taken that the unique key of the detail line items should be given in the select statement.
If the table on which the For All Entries IN clause is based is empty, all rows are selected into the destination table. Hence it is advisable to check before-hand that the first table is not empty.
If the table on which the For All Entries IN clause is based is very large, the performance will go down instead of improving. Hence attempt should be made to keep the table size to a moderate level.
If you using less than 1000 records then it is better to populate those entries into a range then you can use that in the select as IN option.
If the entries are more 1000 records then it is better to use below logic
describe table r_ebeln  lines dl_lines.
    if dl_lines >= 1.
      clear: dl_start, dl_end.
      do.
        dl_start = dl_end + 1.
        dl_end = dl_end + 1000.
        if dl_end > dl_lines.
          dl_end = dl_lines.
        endif.
        refresh: r_ebeln_temp. clear r_ebeln_temp.
        append lines of r_ebeln from dl_start to dl_end to r_ebeln_temp.
        select ebeln "PurNo
               bukrs "ComapnyCode
               ernam "Name
               ekgrp "PurGRp
               waers "Currency
               bedat "Date
             from ekko
             appending  table it_ekko
             where ebeln in r_ebeln_temp.
        if dl_end >= dl_lines.
          exit.
        endif.
      enddo.