explain select ss, ARRAY(select id from foo where ss0 and id between
7 and 156 order by random() limit 3) as v from
generate_series(1,100) ss;
QUERY PLAN
Function Scan on
Hello
2009/2/24 Grzegorz Jaśkiewicz gryz...@gmail.com:
explain select ss, ARRAY(select id from foo where ss0 and id between
7 and 156 order by random() limit 3) as v from
generate_series(1,100) ss;
QUERY PLAN
Question to core developers
if I rank() a table, grouping by foo - but only will want to get first
X result for every rank.
Will postgresql be able to optimize that, or is it something left over
for 8.5 in general?
--
GJ
--
Sent via pgsql-performance mailing list
Excellent. I'll take a look at this and report back here.
Ross
On Mon, Feb 23, 2009 at 04:17:00PM -0500, Tom Lane wrote:
Ross J. Reedstrom reeds...@rice.edu writes:
Summary: C client and large-object API python both send bits in
reasonable time, but I suspect there's still room for
Tom Lane wrote:
Kouber Saparev kou...@saparev.com writes:
Now the planner believes there're 910 rows, which is a bit closer to the
real data:
swing=# select avg(length) from (select username, count(*) as length
from login_attempt group by username) as freq;
avg
The result set should have 31 rows, that is correct.
On Mon, Feb 23, 2009 at 7:53 PM, Scott Marlowe scott.marl...@gmail.comwrote:
On Mon, Feb 23, 2009 at 6:24 PM, Farhan Husain russ...@gmail.com wrote:
This sort here:
- Sort (cost=565372.46..568084.16 rows=1084680 width=74) (actual
On Tue, Feb 24, 2009 at 1:28 AM, Claus Guttesen kome...@gmail.com wrote:
I am doing a performance comparison between running Jena with MySQL and
Postgres. I used the 8.3-community version of Postgres and MySQL 5.0.67.
I
have run several queries to both MySQL and Postgres and all of them
Query:
select A0.Subj, A2.Obj From jena_g1t1_stmt A0, jena_g1t1_stmt A1,
jena_g1t1_stmt A2 Where
A0.Prop='Uv::http://prismstandard.org/namespaces/1.2/basic/isPartOf' AND
A0.Obj='Uv::http://www.utdallas.edu/~farhan.husain/IngentaConnect/issue1_1'
AND A0.GraphID=1 AND A0.Subj=A1.Subj
Can you please elaborate a bit?
I thought that A0.Prop would ignore the composite index created on the
columns subj and prop but this does not seem to be the case.
Yeah, I think you're barking up the wrong tree here. I think Tom had
the correct diagnosis - what do you get from show work_mem?
