how to use modify inside a loop at group block?

[former_member625844]

I have internal table like below.

Month number Index

-----------------------------------

1 5

1 6

2 3

---------------------------------------

Now I want to add index based on month. The result will like below

Month number Index

-----------------------------------

1 5 1

1 6 2

2 3 1

---------------------------------------

I want to use loop group to implement.

The code is like below.

loop at itab into data(wa)
    location = sy-tabix.
    loop at group wa into data(wa1)
       wa1-index = sy-tabix - location.
       modify itab from wa1.
    endloop.
end loop.

But the modify line has error like

"DELETE itab." 和 "MODIFY itab FROM wa." can't use in  "LOOP AT itab ... USING KEY keyname ..." <br>

Then what's the correct syntax to write back to the itab? Thx.

[former_member625844]

I have internal table like below.

Month number Index

-----------------------------------

1 5

1 6

2 3

---------------------------------------

Now I want to add index based on month. The result will like below

Month number Index

-----------------------------------

1 5 1

1 6 2

2 3 1

---------------------------------------

I want to use loop group to implement.

The code is like below.

loop at itab into data(wa)
    location = sy-tabix.
    loop at group wa into data(wa1)
       wa1-index = sy-tabix - location.
       modify itab from wa1.
    endloop.
end loop.

But the modify line has error like

"DELETE itab." 和 "MODIFY itab FROM wa." can't use in  "LOOP AT itab ... USING KEY keyname ..." <br>

Then what's the correct syntax to write back to the itab? Thx.

[MateuszAdamus]

Hi loki_luo15

You cannot modify the internal table inside the group loop: "The internal table itab cannot be modified in the group loop unless the addition WITHOUT MEMBERS is specified.".

https://help.sap.com/doc/abapdocu_751_index_htm/7.51/en-us/abaploop_at_itab_group_by.htm.

Regards,
Mateusz

[Sandra_Rossi]

Your code doesn't make sense: how can you use LOOP AT GROUP inside a loop which doesn't use GROUP BY? Moreover, probably you didn't understand that MODIFY itab FROM wa1 modifies the line currently iterated by LOOP AT itab, so it's useless doing it several times (inside a secondary loop). As what you want to achieve is unclear, I cannot propose a solution.

[former_member625844]

@sandra.rossi. My mistake. The outer loop should be loop at itab into data(wa) group by wa-month. Then inside I will loop through this month's record and asign index to each.

[nandini_borse]

Issue resolve ? if yes, please put your code here.

Thanks !!

[venkateswaran_k]

Hi

loop at itab into data(wa)
    location = sy-tabix.
    loop at group wa into data(wa1)
       wa-index = sy-tabix - location.            <== use wa-index
       modify itab from wa INDEX location.        <== use INDEX keyword
    endloop.
end loop.