Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> Typically, the DatumGetBlah() function that you pick should match the
> SQL data type that the function is returning. So if the function
> returns pg_catalog.int4, which corresponds to the C data type int32,
> you would use DatumGetInt32. There is no SQL type corresponding to the
> C data type uint32, so I'm not sure why we even have DatumGetUInt32.
xid?
regards, tom lane