In the Koha Manual, for Macros in the Advanced Editor in this section: https://koha-community.org/manual/latest/en/html/cataloging.html#advanced-editor-cataloging All the examples show updating specific subfields, so you have to just guess that you can update the contents of a control field (MARC 00x$) by just leaving out the subfield codes. (Like 000$, 001$... etc.) We should add an example of one of these leader fields.
+1. I had no idea! There is no hint that this can be done in the manual or in the macro wiki. It would be great to have it documented.
Phillip, could you add an example here? Are you adding/replacing an entire control field or are you editing specific character positions?
Hi Holly, I think both would work. For example to add some values to the 000 leader field at certain positions, the macro would be: 000= nam a22 7a 4500 No subfield mentioned, just "000".
Thank you! Your example is similar to what I've been able to do, which is use macros to populate an entire fixed data field with certain values. I don't believe there is a way to edit the values of specific positions in a pre-existing 000, 008 (etc) field without replacing all data in the field.