Re: Suggestion for optimization

"Dann Corbit" <DCorbit@connx.com> writes:

> It would be nice if total table cardinality could be maintained live.
> So (after the initial vacuum) we update the cardinality for each table
> in the system table (or perhaps add an entry to the table itself).
> There are two reasons why this is an important optimization.  Firstly,
> it is a psychological benefit for both benchmarks and customers when
> doing a select count(*) from <tablename>.  This is something that pops
> up all the time in benchmarks and customers do it too, in order to get a
> feel for speed.  By storing the current number and incrementing for
> every insert and decrementing for every delete, the count(*) case with
> no where clause can return the value instantly.

How would this work with MVCC?

-Doug
-- 
Doug McNaught       Wireboard Industries      http://www.wireboard.com/
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