Hi Ian, Maybe you might want to ask this question on the Jackrabbit dev list where JCR Query implementation specialist is also lurking.
Regards Felix Ian Boston schrieb: > yes it was that thread that triggered the concern. > > " > Obviously, a stupid example, but, unfortunately, not really to much to > do about it except not sorting on large property fields...if you need to > sort on the title of 200.000 docs...you better sort on the short_title > (which I would prefer to be an index only property defined in > indexing_configuration, but I think people have different opinions on > this) " > > Does that mean that sorting huge numbers of documents on *small* fields > has a similar problems. Unless there is a pre-query to estimate the > number of hits (using the Jackrabbit getTotalCount() IIRC methods), then > its going to be impossible to avoid submitting queries that could result > in a sort on huge numbers of results. > > I had thought in the special case of sort by date the solution would be > to split the searches up into chunks to avoid a massive sort. > > eg search for items in the last hour, > if there are not enough items the next hour with some extending range. > > or perform a sequence of unsorted pre queries on a date range to > determine the range required to return a set large enough to sort. > > On the basis that lastModified is a long, am I worrying unnecessarily ? > > Ian > > > On 15 Jun 2009, at 17:59, Marc Speck wrote: > >> I've just read the thread http://markmail.org/message/wnn2bfwzwx2hn6v4 . >> Maybe it helps, >> Marc >> >> >> >> On Mon, Jun 15, 2009 at 6:52 PM, Ian Boston <i...@tfd.co.uk> wrote: >> >>> Hi, >>> >>> I want to perform a query where the full result set could be millions of >>> items. That set needs to be sorted by the lastModified attribute on the >>> node, and I only want to see a small number of items eg 100 after a >>> particular date. >>> >>> If I do this, will there be scalability issues, or is the sorting of >>> a date >>> field optimized in the query engine ? >>> >>> Thanks >>> Ian >>> > >
