Given you can attach multiple database files in sqlite, perhaps it could
be extended such that:
* When you name an index, you optionally prepend the database name
which can be in another currently attached db
* You attached to multiple db files that have cross references as:
o begin
oattach database tables.sqlite3 as tables
oattach database indices.sqlite3 as indices
o end
The idea being that all the xref checks happen at the end of the
transaction.
If you attach to a file with external refererences that are not found at
the end of the transaction it fails.
If you reference any tables without current xrefs complete (e.g., put a
'select' or 'insert' between 2 attach statements above)
then it fails because the referenced table is 'inactive' due to pending
xrefs.
The advantages of allowing extension are:
* backward compatible to previous usage
* likely better performance due to locality and caching
o Some queries only need the index
* manage indices better, for optimal performance 1 index per file
for a really big index
Big distruptive code change?
