The mappings listed under 'Biblios' and 'Authorities' are draggable - this allows ordering of fields.
The ordering affects the id field in the search_marc_map table
When retrieving for display or mapping we are not ordering by the this field.
In general I am not sure if we are gaining anything with this ordering:
" When sorting on fields with more than one value, remember that the values do not have any intrinsic order; a multivalue field is just a bag of values. Which one do you choose to sort on?"
I think we can switch to the idea that a single field per index should be chosen for ordering:
author = 100 (only make this one sortable)
author = 700
author = 245c
or, in the case of authorities, we should expect a single field to populate the field for sorting (100, 110, 150 ... are alldefined as 'main-heading' - but each record should only have a single one of these field)
*** Bug 19922 has been marked as a duplicate of this bug. ***