=== Short-version ===
Is there a way to join on the complement of a query? I want the only the
Solr documents for which the nested join query does not match.
=== Longer-version ===
Query-time joins with {!join} are great at modeling the SQL equivalent of
patterns like this:
SELECT book_name FROM books WHERE id
IN (SELECT book_id FROM chapters WHERE chapter_title = "Foo")
This would find the name of books having chapters entitled "Foo". (Assuming
the chapters table have the column 'book_id' that point back to the book
record containing them.)
That's great.
Is there a way in Solr to query for the complement of that? In SQL terms,
this:
SELECT book_name FROM books WHERE id
NOT IN (SELECT book_id FROM chapters WHERE chapter_title = "Foo")
This would find books that do not have chapters entitled "Foo".
It isn't the same as querying (in Solr terms) for something like
{!join to=id from=book_id}-chapter_title:"Foo" // note the negation
because it would still match other chapters in the same book that are not
entitled "Foo", causing the join to still identify the book based on its
other non-Foo chapters.
Any advice would be greatly appreciated. I'm also open to other ways of
thinking about the problem. Perhaps there are alternative indexing patterns
that could accomplish the same goal.
Many thanks,
Bruce
