  We present a re-analysis of the Geneva-Copenhagen survey, which benefits from
the infrared flux method to improve the accuracy of the derived stellar
effective temperatures and uses the latter to build a consistent and improved
metallicity scale. Metallicities are calibrated on high-resolution spectroscopy
and checked against four open clusters and a moving group, showing excellent
consistency. The new temperature and metallicity scales provide a better match
to theoretical isochrones, which are used for a Bayesian analysis of stellar
ages. With respect to previous analyses, our stars are on average 100 K hotter
and 0.1 dex more metal rich, which shift the peak of the metallicity
distribution function around the solar value. From Stromgren photometry we are
able to derive for the first time a proxy for alpha elements, which enables us
to perform a tentative dissection of the chemical thin and thick disc. We find
evidence for the latter being composed of an old, mildly but systematically
alpha-enhanced population that extends to super solar metallicities, in
agreement with spectroscopic studies. Our revision offers the largest existing
kinematically unbiased sample of the solar neighbourhood that contains full
information on kinematics, metallicities, and ages and thus provides better
constraints on the physical processes relevant in the build-up of the Milky Way
disc, enabling a better understanding of the Sun in a Galactic context.
