Peter,

What is a bitset?  Is it a Java class or a more primitive data
structure?

Alan


On 19-Jan-07, at 2:32 PM, Binkley, Peter wrote:

> This is why I think we should figure out smart ways to manage facets
> independently of Lucene index fields. Solr populates a facet by
> setting
> up a bitset for every value found in a given index field, and it uses
> those bitsets to filter query result sets by deriving an intersection
> set. We can extend that functionality by populating and maintaining
> bitsets based on external data sources that can map to Lucene document
> ids. This allows us to update the bitset (relatively cheap) without
> having to update the index (relatively expensive).