Bruce Momjian wrote:
> The larger problem is that count(*) doesn't use the index at all. It
> just does a sequential scan of the heap table.
Here is another example, which is even worse:
select value from table where id=1 order by epoch desc limit 1;
to ask for the last stored value.
This request needs about 5 minutes to complete.
(But please consider that the postgres server has some other requests
The machine running this server is an alpha server with Tru64)
The explain statements results in:
explain select * from table where id=1 order by epoche desc limit 1;
NOTICE: QUERY PLAN:
Sort (cost=12692.74 rows=202175 width=16)
-> Index Scan using wetter_pkey on table (cost=12692.74 rows=202175
In response to
pgsql-sql by date
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