Continuing to look at this patch ... I'm wondering if any particular
discussion went into choosing the FDW option names "nspname", "relname",
and "colname". These don't seem to me like names that we ought to be
exposing at the SQL command level. Why not just "schema", "table",
"column"? Or perhaps "schema_name", "table_name", "column_name" if you
feel it's essential to distinguish that these are names.
regards, tom lane