Crystallography Online: the website of the International Union of Crystallography

I find it strange that the 'array_id' is not a complete array reference.
For example, in the new MAP category, a MAP array reference requires
both the array_id and the binary_id:

  _map_segment.array_id
  _map_segment.binary_id

It is also confusing that array_id is really an _array_structure.id. Is
a given _array_structure.id supposed to be unique for a given array? If
so, why doesn't it include a binary_id reference?

If _array_structure.id is not intended to be unique, so that multiple
binary arrays with the same format can reference the same
_array_structure.id, then doesn't it make sense for 'array_id' to be a
reference to a name given to the _array_data category?

If neither of the two are meant to be unique, why not define a simple
_array category:

   _array.id
   _array.array_structure_id
   _array.binary_id

This would make the most sens if the 'array_id' used everywhere points
to the above _array.id name.

Is there a reason not to have a name for each unique array? Is it a good
idea, but we are now stuck with a rather messed up organization for
historical purposes?

Joe Krahn