I created a custom DocType “Release info” and added a custom field “Author”.
I would like the “Author” field to be automatically filled in with the name of the user that created the new Release info document. For example, I created a new release info, and I want the “Author” field to be automatically updated with my name.
First set your field like Author Link with User so change Options Doctype → User
Created by Or Logging user both are same so set default value like __user (2-time underscore) then check it when you create a document then logging id/Created by id show in Author field.
For that case, you can manually insert the author in a field.
Otherwise, if its doctype is master then export it after updating an author field then import them.
OR
Bulk Edit: Going to doctype list for bulk edit, the first filter set created by then created by document select after go to action button and click edit button after select author name and created user id select and check it.