Subject: Poor performance with "large" table.
From: "Jack Gao" <weigao@hotmail.com>
===
Hi, List
I have two questions about PostgreSQL on Windows platform. I install
postgresql 7.2.1 from cygwin. and running psql from cygwin also.
1. I'm keeping get error message when I use psql to get "large" data. For
example, if one of my table has more than 74 records in it, when I run
"select * from tbl...." on psql, it give me "less: not found" message. Also,
if I run "\df" on psql, I got same message. But if I run "\df to_char", I
got the inform I want. Looks like psql can not showing too much data. But
what this error message mean, and how to fix it?
2. I have a table has about 208458 records in it, and I tried "vacuum
analyze" on my database before I doing this test.
When I run "explain select count(*) from tblTest;" it give me something
like:
============================================================================
========
NOTICE: QUERY PLAN:
Aggregate (cost=4618.73..4618.73 rows=1 width=0)
-> Seq Scan on tbltest (cost=0.00..4097.58 rows=208458 width=0)
EXPLAIN
============================================================================
========
and I got result in seconds.
When I run "explain select * from tblTest;", it give me something like:
============================================================================
========
NOTICE: QUERY PLAN:
Seq Scan on tbltest (cost=0.00..4097.58 rows=208458 width=38)
EXPLAIN
============================================================================
========
But I got that error message after about 10 minutes.
200k record is not that large I think. Is it something wrong with my
installation?
I didn't got chance to test it on Linux platform yet, I will post the result
after I do the same test on Linux platform.
Thanks and regards,
Jack