I'm using field collapsing to group documents by a single field and have run
into something unexpected with how sorting of the groups works. Right now I
have each group return one document. The documents within each group are sorted
by a field ("price") in ascending order using group.sort so that the document
returned for each group in the search results is the cheapest document of the
group. If I sort the groups amongst themselves using sort=price asc, I get what
I expect with groups having documents whose lowest price value is low show
first and groups having documents whose lowest price value is high show last.
If I change this to sort on price desc, what happens is not what I would
expect. I would like the groups to be returned in reverse order from what
happened when sorting by price asc. Instead, what happens is the groups are
sorted in descending order according to the highest priced document in each
group. I want groups to be sorted in descending order according to the lowest
priced document in each group, but it appears this is not possible. In other
words, it appears sorting when groups are involved is limited to either
MAX([field]) DESC or MIN([field]) ASC. The other two combinations are not
possible. Does anyone know whether or not this is in fact impossible, and if
not, how I might put in a feature request?
