How to change output length in Query

Dear experts,

I need to change the output length of a field in an already existing query. I do this following these steps but the length is still the same, could you please let me know if I'm doing something wrong?

1. Transaction SQ01, select the query name.

2. Basic list. Select the field "Denom", double click and in the bottom left, I change the standard lenght from 40 to 10 and press the button "Apply" Now I can see that the basic list is shorter for that field.

3. Save the values and execute the query

4. The 40 characters are still visible....

Do you know why and how I can solve this?

Thanks in advance,

Regards,

Rebeca