Connecting to PostgreSQL server with Qt5.4

Hendrik4.10

Hey guys,
I want to create an application which uses a PostgreSQL database on a dedicated server.
I've installed the drivers and I'm about to initialize my connection like this:

DBConnection = QSqlDatabase::addDatabase("QPSQL");
DBConnection.setHostName(dbHost);
DBConnection.setDatabaseName(dbName);
DBConnection.setUserName(dbUser);
DBConnection.setPassword(dbPass);
if(DBConnection.open()){
    qDebug() << "Succesfully Connected";
} else {
    qDebug() << "Connection Error";
    qDebug() << DBConnection.lastError().text();
}

The value of dbHost is the IP adress of the server.
If I run the programm, I get this output:

Connection Error
could not connect to server: File or directory not found
Is the server running locally and accepting
connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?

For me it looks like the driver wants to connect to localhost, even if I enter an IP adress as the host.
Is there a way to solve my problem, without writing a complete new driver?

Greetings
Hendrik

mcosta

Hi and welcome to devnet,

are you sure dbHost is set correctly?

Hendrik4.10

I've set dbHost like this:

const QString dbHost = "192.168.178.26";

mcosta

Weird,

can you debug the code and verify the value of variables?

SGaist

Hi and welcome to devnet,

To add to @mcosta, and maybe a silly question bug are you sure that you are using the corrected address and not the one from own computer ?

clochydd

Hi, to check the connection: can you access your database with the same parameters (host, port etc.) via pgAdmin?

saim

I was able to remotely access Postgres database on a different PC.
This video was very helpful.
https://www.youtube.com/watch?v=4IhfbxhoAn8
Basically you need to open the windows firewall (or create an exception for the port) and change the line
host all all 127.0.0.1/32 scram-sha-256
to
host all all 0.0.0.0/0 scram-sha-256 in the pg_hba.conf file.