Re: Postgres + Xapian (was Re: fulltext searching via a

Hannu Krosing wrote:
> Eric Ridge kirjutas R, 09.01.2004 kell 01:16:
> 
> > Forgetting about composite indexes for a moment, is postgres even 
> > capable of doing 2 index scans in this situation?  Does it know how do 
> > take the intersection of two scans?
> 
> Not currently, but it has been in TODO for quite some time:
> 
> * Use bitmaps to fetch heap pages in sequential order [performance]
> * Use bitmaps to combine existing indexes [performance]

And this the foundation of bitmapped indexes, as I understand it, and is
used for "star" joins, popular with data warehousing.

Rather than use those terms, I spelled out the actual behavior we want.

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