If you're easily able to do it, (i.e. you're building rather than receiving
the query), you could rank them by the conjunction of the search terms
first:

ORDER BY ts_rank(vector, to_tsquery('A & B & C')) desc, ts_rank(vector,
to_tsquery('A | B | C')) desc

Or just explicitly order by whether the conjunction matches:

ORDER BY case when to_tsquery('A & B & C') @@ vector then 0 else 1
end, ts_rank(vector, to_tsquery('A | B | C')) desc

I think either of these would have the property you want, but I don't know
how they would otherwise affect the quality of the ranking.  You should set
up a test group of documents and make sure your mechanism ranks that group
properly on test queries.

Joel

On Tue, Sep 25, 2012 at 11:16 AM, W. Matthew Wilson <m...@tplus1.com> wrote:

> I want to run a query like to_tsquery("A | B | C") and then rank the
> results so that if a document contained A, B, and C, then it would
> rank above a document that just had some subset.
>
> How would I do such a thing?
>
> --
> W. Matthew Wilson
> m...@tplus1.com
> http://tplus1.com
>
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