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/*
* testlibpq2.cc
* Test of the asynchronous notification interface
*
populate a database with the following:
CREATE TABLE TBL1 (i int4);
CREATE TABLE TBL2 (i int4);
CREATE RULE r1 AS ON INSERT TO TBL1 DO [INSERT INTO TBL2 values (new.i); NOTIFY TBL2];
* Then start up this program
* After the program has begun, do
INSERT INTO TBL1 values (10);
*
*
*/
#include <stdio.h>
#include "libpq++.H"
main()
{
char* dbName;
int nFields;
int i,j;
/* begin, by creating the parameter environtment for a backend
connection. When no parameters are given then the system will
try to use reasonable defaults by looking up environment variables
or, failing that, using hardwired constants */
PGenv env;
PGdatabase* data;
PGnotify* notify;
dbName = getenv("USER"); /* change this to the name of your test database */
/* make a connection to the database */
data = new PGdatabase(&env, dbName);
/* check to see that the backend connection was successfully made */
if (data->status() == CONNECTION_BAD) {
fprintf(stderr,"Connection to database '%s' failed.\n", dbName);
fprintf(stderr,"%s",data->errormessage());
delete data;
exit(1);
}
if (data->exec("LISTEN TBL2") != PGRES_COMMAND_OK) {
fprintf(stderr,"LISTEN command failed\n");
delete data;
exit(1);
}
while (1) {
/* check for asynchronous returns */
notify = data->notifies();
if (notify) {
fprintf(stderr,
"ASYNC NOTIFY of '%s' from backend pid '%d' received\n",
notify->relname, notify->be_pid);
free(notify);
break;
}
}
/* close the connection to the database and cleanup */
delete data;
}
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