From: Joachim Wieland <joe@mcknight.de>
To: andy rost <andy.rost@noaa.gov>
Cc: pgsql-interfaces@postgresql.org
Subject: Re: Using FETCH ALL with descriptor areas
Date: Tue, 1 Aug 2006 09:39:48 +0200
Message-ID: <20060801073948.GA2236@mcknight.de> (raw)
In-Reply-To: <44CA74FA.5010305@noaa.gov>
References: <44CA74FA.5010305@noaa.gov>
On Fri, Jul 28, 2006 at 03:35:06PM -0500, andy rost wrote:
> Is it possible, in ECPG, to use FETCH ALL with descriptor areas? If so,
> can anyone provide a simple example. If not, does anyone have a get
> around. We've found FETCH NEXT to be pretty expensive when selecting
> even a modest number of tuples.
I don't know if it is what you're looking for nor if it is faster at all but
I attach an example with descriptors and auto-allocation.
Joachim
--
Joachim Wieland joe@mcknight.de
GPG key available
#include <stdio.h>
exec sql include sqlca;
#include <stdlib.h>
exec sql include ../regression;
int main(void)
{
exec sql begin declare section;
int *ip1=0;
char **cp2=0;
int *ipointer1=0;
int *ipointer2=0;
int colnum;
exec sql end declare section;
int i;
ECPGdebug(1, stderr);
exec sql whenever sqlerror do sqlprint();
exec sql connect to REGRESSDB1;
exec sql create table test (a int, b text);
exec sql insert into test values (1, 'one');
exec sql insert into test values (2, 'two');
exec sql insert into test values (NULL, 'three');
exec sql insert into test values (4, 'four');
exec sql insert into test values (5, NULL);
exec sql insert into test values (NULL, NULL);
exec sql allocate descriptor mydesc;
exec sql select * into descriptor mydesc from test;
exec sql get descriptor mydesc :colnum=COUNT;
exec sql get descriptor mydesc value 1 :ip1=DATA, :ipointer1=INDICATOR;
exec sql get descriptor mydesc value 2 :cp2=DATA, :ipointer2=INDICATOR;
printf("Result (%d columns):\n", colnum);
for (i=0;i < sqlca.sqlerrd[2];++i)
{
if (ipointer1[i]) printf("NULL, ");
else printf("%d, ",ip1[i]);
if (ipointer2[i]) printf("NULL, ");
else printf("'%s', ",cp2[i]);
printf("\n");
}
ECPGfree_auto_mem();
printf("\n");
exec sql deallocate descriptor mydesc;
exec sql rollback;
exec sql disconnect;
return 0;
}
Attachments:
[text/plain] dynalloc2.pgc (1.4K, ../20060801073948.GA2236@mcknight.de/2-dynalloc2.pgc)
download | inline:
#include <stdio.h>
exec sql include sqlca;
#include <stdlib.h>
exec sql include ../regression;
int main(void)
{
exec sql begin declare section;
int *ip1=0;
char **cp2=0;
int *ipointer1=0;
int *ipointer2=0;
int colnum;
exec sql end declare section;
int i;
ECPGdebug(1, stderr);
exec sql whenever sqlerror do sqlprint();
exec sql connect to REGRESSDB1;
exec sql create table test (a int, b text);
exec sql insert into test values (1, 'one');
exec sql insert into test values (2, 'two');
exec sql insert into test values (NULL, 'three');
exec sql insert into test values (4, 'four');
exec sql insert into test values (5, NULL);
exec sql insert into test values (NULL, NULL);
exec sql allocate descriptor mydesc;
exec sql select * into descriptor mydesc from test;
exec sql get descriptor mydesc :colnum=COUNT;
exec sql get descriptor mydesc value 1 :ip1=DATA, :ipointer1=INDICATOR;
exec sql get descriptor mydesc value 2 :cp2=DATA, :ipointer2=INDICATOR;
printf("Result (%d columns):\n", colnum);
for (i=0;i < sqlca.sqlerrd[2];++i)
{
if (ipointer1[i]) printf("NULL, ");
else printf("%d, ",ip1[i]);
if (ipointer2[i]) printf("NULL, ");
else printf("'%s', ",cp2[i]);
printf("\n");
}
ECPGfree_auto_mem();
printf("\n");
exec sql deallocate descriptor mydesc;
exec sql rollback;
exec sql disconnect;
return 0;
}
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To: pgsql-interfaces@postgresql.org
Cc: joe@mcknight.de, andy.rost@noaa.gov
Subject: Re: Using FETCH ALL with descriptor areas
In-Reply-To: <20060801073948.GA2236@mcknight.de>
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