topic Re: Comparing two files in Application Development and Automation Discussions

Comparing two files

Former Member — Wed, 31 Oct 2007 21:43:11 GMT

Hi All,

My problem is I have two files with same structure, but may be having different data. I want to compare those files. I can read those files into two internal tables.

What is the fastest way to compare and determine the differences between the internal tables?

Thanks,

Aravind

Re: Comparing two files

Former Member — Wed, 31 Oct 2007 21:46:35 GMT

I guess you could read them into the two internal tables and sort them. Then loop through one table and read the corresponding record of the second table. Something like:

sort: itab1, itab2.

loop at itab.

read itab2 index sy-tabix.

if itab1 <> itab2.

Do something.

endif.

endloop.

Rob

Re: Comparing two files

Former Member — Wed, 31 Oct 2007 22:32:47 GMT

first sort both the internal tables using some sort key.

then check...

if itab1[] = itab2[].

.....

endif.

Reward if it is useful.

Thanks,

Srinivas

Re: Comparing two files

Former Member — Fri, 02 Nov 2007 15:06:10 GMT

The following coding should be a guidline for an efficient compare of two internal table, using a hashed table for one of the two tables.

It assumes that there new lines, disappeared and chnages lines.

The three table ins_tab, del_tab, upd_tad collect the differences, they must be applied to itab1 to change it into itab2.

Siegfried


data:
  tab1     type tab,
  tab2     type hash.
  refresh  ins_tab.
  refresh  del_tab.
  refresh  upd_tab.

  tab1[] = itab1[].
  tab2[] = itab2[].
  clear wa1.
  clear wa2.


  loop at tab1 into wa1.
    read table tab2 into wa2
         with table key keyfield = wa1-keyfield.
    index1 = sy-tabix.

* entry not in itab2
    if ( sy-subrc ne 0 ).
      append wa1 to del_tab.

* entry in itab2, update if different
    else.
      delete table tab2
             with table key keyfield = wa1-keyfield.
      if ( wa1-ctext ne wa2-ctext ).
        append wa2 to upd_tab.
      endif.
    endif.
  endloop.

* in itab2 but not in itab1
  ins_tab[] = tab2[].