Problem with including Qt libraries

[finngruwier]

It want to familiarize myself with Qt by building a simple console application that can access a SQLite database. Using http://doc.qt.nokia.com/4.7/sql-connecting.html as a reference, I enter this in Qt Creator:

#include <QtSql/QSqlDatabase>
 
int main() {
 
    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
 
}

#include <QtSql/QSqlDatabase>

int main() {

    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");

}

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When I try to build, I get a number of errors similar to: "/(...)/console-1/main.cpp:-1: error: undefined reference to `QSqlDatabase::defaultConnection".

What is wrong?