Bruce Momjian wrote:
> The problem here is that now we don't have commit status in the index
> rows, so they have to check the heap for every row. One idea is to
> update the index status on an index scan, and if we can do that, we can
> easily use the index. However, the table scan is pretty quick.
It certainly works quickly for smaller tables, however the 21.7 million
record table I ran this on takes a touch longer as shown here:
database=# explain select count(*) from table;
NOTICE: QUERY PLAN:
Aggregate (cost=478056.20..478056.20 rows=1 width=0) -> Seq Scan on table (cost=0.00..423737.76 rows=21727376
width=0)
EXPLAIN
However I noted explain provides rows as part of it's data; from what
I've seen this loses precision over time or with large data imports,
though; at least until the table is vacuumed again.
-Casey
