Simon Riggs wrote:
On Sun, 2005-12-18 at 17:07 +1300, Mark Kirkwood wrote:
Tom Lane wrote:
2. transform joins into subselects, then return subselect rows via an
index bitmap. Joins are performed via a bitmap addition process.
Looks like 8.1 pretty much does this right now:
Good analysis.
8.1 doesn't do:
- the transforms sufficiently well (you just performed them manually)
Absolutely - I was intending to note that very point, but it got lost
somewhere between brain and fingers :-)
- doesn't AND together multiple bitmaps to assist with N-way joins
Ah yes - I had overlooked that, good point!
Cheers
Mark
