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This is probably stupid for some reason, but why not use a 64-bit integer to track the number of records in the table? Increment when adding records, decrement when deleting them... then COUNT(*) could just return that in cases where a query is known to be looking at all of the records?
On Jan 14, 2005, at 12:04 PM, Wes wrote:
On 1/13/05 6:44 PM, "Greg Stark" <[EMAIL PROTECTED]> wrote:
That's simply false. Oracle does indeed have to count the records one by one.
It doesn't have to read and ignore the dead records since they're in a
separate place (but on the other hand it sometimes have to go read that
separate place when it sees records that were committed after your
transaction).
It can also do index-only scans, which often helps, but it's still not instantaneous.
Ok, I stand corrected - I was given some wrong information. However, my
experience has been that count(*) on Oracle is a whole lot faster than
PostgreSQL - what appeared instantaneous on Oracle took some time on
PostgreSQL. That was one of the first things I noticed when moving a
database application to PostgreSQL. I've since disposed of the Oracle
database, so can't go back and retest.
Wes
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