[mythtv] Renewing PostgreSQL support

[Richard Morton]

MySQL is optimised for many read operations and many fewer write operations.
MySQL used to be lacking on features compared to PostgresSQL and in
some ways still is; but it is much faster. As MySQL is sufficient for
the needs of Myth, what is the motivation behind wanting to work on a
PostgreSQL version?

I would expect that mSQL or SQLlite is sufficient for Myth; epecially
if the clients could be re-engineered to proxy requests to the db via
the backends.