Test that PG::Connection#escape_literal-less Mao.escape_literal works with
binary data.
Specify error handling at all levels.
Reconnection.

Do JOINs without all the "c1" "c2" "c3" business; assume (= check we can
assume) that the primary table's columns come first, and secondary table's
after; then just pick off the first n cols of a result tuple (where n is number
of cols in primary table) and assign them to the primary table, and the
remaining m (where m is no. of cols in secondary) to secondary.