Inherited description: Advance the procedural result set cursor to the next row. Returns 0 if the cursor is at the end of the
result set or if an error was encountered. Errors are reported in dynamic SQL using the %SQLCODE and %Message
properties of the statement result. An optional argument will contain a %Status value on return. This %Status value
indicates success or failure of the %Next call but it should be considered to be a secondary error reporting interface,
%SQLCODE being the primary error reporting mechanism.
This implementation can be overridden by classes that implement the procedural cursor interface.