Adding other factors into ranking

adam.cooper · Post by **adam.cooper** » Tue Dec 16, 2003 5:54 am

I would like to be able to scale the existing ranking (or adjust record order) depending on the category, for example. E.g. to allow a user to declare that they prefer a certain type of information and have hits for other types pushed down the list.

So:
1. am I correct in assuming that the ranking is a black box except for the various knobs to do with proximity, lead etc
2. does the rank get calculated before ORDER BY and IF there is an ORDER BY, this will re-order the previously-rank-ordered dataset.
3. would it be possible to ORDER BY a calculated value such as (rank+category_weighting*200)?

Cheers

Post by **John** » Tue Dec 16, 2003 8:16 am

Yes, you can use a calculated rank value. There is an example using dates in the April 2003 Newsletter: http://www.thunderstone.com/texis/site/ ... 00302.html

You can use an expression in the ORDER BY clause as well, and if all the fields needed are present in the compound metamorph index it will calculate that during index lookup, and save the time needed for a later sort.