Re: Suggestion for optimization

On Fri, 5 Apr 2002, Barry Lind wrote:

> Af far as I know Oracle doesn't have any short cut (along the lines of 
> what is being discussed in this thread) for this operation.  However 
> Oracle is more efficient in providing the answer than postgres currently 
> is.  While postgres needs to perform a full scan on the table, Oracle 
> will only need to perform a full index scan on the primary key if one 
> exists.  Since the index will likely have much less data than the full 

Under Postgres, a full index scan is generally more expensive than a full
table scan since indices, particularly btree, carry a large amount of meta
data and theefore consume more pages.

Gavin