Row number in result to fetch. Rows are numbered from 0 upwards. If omitted,
next row is fetched.
A string representing the name of the field (column) to fetch, otherwise
and int representing the field number to fetch. Fields are
numbered from 0 upwards.
Boolean is returned as "t" or "f". All
other types, including arrays are returned as strings formatted
in the same default PostgreSQL manner that you would see in the
psql program. Database NULL
values are returned as NULL.
FALSE is returned if row exceeds the number
of rows in the set, or on any other error.