/* * testlibpq4.cc * Test of the asynchronous notification interface * populate a test database with the following (use testlibpq4.sql): 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 #include #include main() { // Begin, by connecting to the backend using hardwired constants // and a test database created by the user prior to the invokation // of this test program. char* dbName = getenv("USER"); // change this to the name of your test database PgDatabase data(dbName); // Check to see that the backend connection was successfully made if ( data.ConnectionBad() ) { cerr << "Connection to database '" << dbName << "' failed." << endl << data.ErrorMessage() << endl; exit(1); } // Listen to a table if ( !data.ExecCommandOk("LISTEN TBL2") ) { cerr << "LISTEN command failed" << endl; exit(1); } // Test asynchronous notification while (1) { // check for asynchronous returns PGnotify* notify = data.Notifies(); if (notify) { cerr << "ASYNC NOTIFY of '" << notify->relname << "' from backend pid '" << notify->be_pid << "' received" << endl; free(notify); break; } } }