When you connect to a database with PQsetdb, as with psql, depending on
how your uninitialized variables are set, you can get a failure with a
"There is no connection to the backend" message.
The fix is to move a call to PQexec() from inside connectDB() to
PQsetdb() after connectDB() returns to PQsetdb(). That way a connection
doesn't have to be already established in order to establish it!