Re: [greenstone-devel] Cross-Collection Searching

From Mark Sullivan
DateTue, 23 Aug 2005 21:37:39 -0400
Subject Re: [greenstone-devel] Cross-Collection Searching
So, a couple points..

1) Apparently you cannot build "Cross-Collection Searching" in a collection
unless it has an item. So, I made a fake item to "allow" that type of
searching. Rebuilt the collection with one item, and cross-collection
searching works fine.

2) But.. there really aren't any cross-collection indexes it appears. And
you don't even need to tell the collection to allow cross-collection
searching... just edit the URL and you can search across any number of
collections. Perhaps this is because my indexes are similar, but this will
remain true.

3) Given that cross-collection searching does not build a cross-collection
index, I am thinking of running my own search against each collection
independently, and then merging the results. So, can someone explain if the
'Ranking' system in advanced searching really works? Could I get this
'Rank' out from the search somehow? So I could then merge 3-4 ranked lists?
Does this currently happen in the web interface? Or does this ranking
really go out the window when you start cross-collection searching.

I must say, I understand there are some inherent problems in trying to rank
across collections. If you are searching for information on Thomas Edison,
then a collection ABOUT Thomas Edison, or inventors, 50% rank is almost
certainly higher than a rank of that in an unrelated collection. But
still.. some sort of ability to merge search result lists would be nice.

Thank you,

Mark Sullivan
Systems Programmer
University of Florida
(352) 846 - 0129


-----Original Message-----
From: Mark Sullivan
To: ''
Sent: 8/21/05 8:19 PM
Subject: Cross-Collection Searching

I am trying to build collections which are ONLY used for
cross-collection searching. As such, they have no actual items in their

When I preview the collection, the search options are limited to TEXT
and ALLFIELDS, instead of the many other options which the two
collections in this cross-collection search share.

Do I need to add an item to the cross-collection-searching collectoin
with this type of metadata to make this work?

Is anyone building collections which contain NO items... only other
collections for this type of searching?

Thank you for any help...

Mark Sullivan
Systems Programmer
University of Florida Digital Collections