On Mon, 2006-02-20 at 16:40, Martijn van Oosterhout wrote: > On Mon, Feb 20, 2006 at 05:08:33AM -0800, Chad wrote: > > 4. Why I think I need to work at this level of abstraction. I believe, > > certain types of queries can be realized more efficiently by code that > > can seek to specific parts of an index and immediately returning a > > small number of rows to the client. The query would remain active and > > the client would only retrieve the next rows after the previous cursor > > position when the client was ready to do so. With a huge underlying > > <snip> > > You realise you can acheive almost exactly what you want here by saying > things like: > > DECLARE c AS CURSOR FOR select * from table where name >= 'Mal' order by name; > FETCH FORWARD 1; -- Go down > FETCH FORWARD 1; -- Go down > FETCH BACKWARD 2; -- Go back again > > If you have an index it will just step through the index to find the > rows you want. While you're free to try and make this work by using the > index code directly, you're not asking anything that's otherwise > impossible. I think the problem here is that when you have a hammer, everything looks like a nail. We see it with people coming from Oracle or DB2 as well. "I learned it this way" is often a bigger obstacle to learning postgresql than no knowledge at all.
