Re: [PERFORM] Bitmasks

Ivan Voras <[EMAIL PROTECTED]> writes: > select * from tt where (flags & 16) != 0; > > I suspected radix trees could be used for this but it seems it doesn't work > that way. You would need a gist index method to make this work. I actually worked on one for a while and had it working. But it was

[PERFORM] Bitmasks

Can indexes be used for bit-filtering queries? For example: create table tt ( flags integer not null default 0, str varchar ); select * from tt where (flags & 16) != 0; I suspected radix trees could be used for this but it seems it doesn't work that way. If not, is there a way of quick

Re: [PERFORM] Queries taking ages in PG 8.1, have been much faster in PG<=8.0

On Mon, 05 Dec 2005 10:11:41 -0500, Tom Lane <[EMAIL PROTECTED]> wrote: >> Correlation -0.0736492 >> Correlation -0.237136 >That has considerable impact on the >estimated cost of an indexscan The cost estimator uses correlationsquared. So all correlations between -0.3 and +0.3

Re: [PERFORM] Clustered tables and seqscan disabled

Henrique Engelmann <[EMAIL PROTECTED]> writes: > I suggested changing the application and including a order by clause... but > the software house didn´t make it because they said the system was originally > designed for oracle and they did not need to use the ORDER BY clause with > Oracle and

Re: [PERFORM] Executing a shell command from a PG function

Thanks Michael and Jaime. The pg/sh thing is probably what I was looking for. Tnx Michael Fuhr wrote: On Sat, Dec 10, 2005 at 04:55:56PM +0100, Yves Vindevogel wrote: Is it possible to run a shell script, passing values of fields to it, in a Postgres function ? Not directly from S

Re: [PERFORM] Executing a shell command from a PG function

On Sat, Dec 10, 2005 at 04:55:56PM +0100, Yves Vindevogel wrote: > Is it possible to run a shell script, passing values of fields to it, in > a Postgres function ? Not directly from SQL or PL/pgSQL functions, but you can execute shell commands with the untrusted versions of PL/Perl, PL/Tcl, PL/Py

Re: [PERFORM] Executing a shell command from a PG function

On 12/10/05, Yves Vindevogel <[EMAIL PROTECTED]> wrote: > Hi, > > Is it possible to run a shell script, passing values of fields to it, in > a Postgres function ? > > Yves Vindevogel > search for the pl/sh language -- regards, Jaime Casanova (DBA: DataBase Aniquilator ;)

[PERFORM] Executing a shell command from a PG function

Hi, Is it possible to run a shell script, passing values of fields to it, in a Postgres function ? Yves Vindevogel begin:vcard fn:Yves Vindevogel n:Vindevogel;Yves org:Implements adr:;;Kempische Steenweg 206;Hasselt;;3500;Belgium email;internet:[EMAIL PROTECTED] tel;work:+32 (11) 43 55 76 tel

[PERFORM] Clustered tables and seqscan disabled

Hi,   Sometime ago I worked in an implantation project that uses postgresql and I remember than the software house recommended us to use seqscan off...I was not very sure, but I thought the best way should be set seqscan on and let postgresql choose the best access plan (index or seqscan). Even a

[PERFORM] Is RAID10 the best choice?

Hello,   I would like to know which is the best configuration to use 4 scsi drives with a pg 8.1 server.   Configuring them as a RAID10 set seems a good choice but now I´m figuring another configuration:SCSI drive 1: operational systemSCSI drive 2: pg_xlogSCSI drive 3: dataSCSI drive 4: index