Most efficient way to achieve this ts_query - Mailing list pgsql-sql

Hi

If someone uses a search query on my site like this:

"abc def"

I would like to return all results for 'abc & def' first, followed by
all results for tsquery 'abc | def' is there some way to express this
in one tsquery?  What's the most efficient way to go about this?  The
search is on one column.

Thanks
Jamie