I am suggesting adding a function to libpq:
PGresult *PQvexec(PGconn *conn, const char *fmt, ...);
It behaves similar to PQexec, but it allows for printf style varargs and
does connection re-establishing if the connection fails (it can be
discussed if this already to much magic, maybe remove this part). It
has been carefully designed to handle memory the right way. We use this
since a long time.
What do you think?
