This function is used to iterate over the HTTP response headers returning the next HTTP response header name. Calling it with
NULL causes it to return the name of the first response header. Subsequent response headers are retrieved by passing the name
of the previous response header to the function. This function returns NULL when called with the name of the last response
header, or if it is not called from a web service.
Calling this function repeatedly returns all the response header fields exactly once, but not necessarily in the order they
appear in the HTTP response.
The following statement displays the name and values of the HTTP response headers in the database server messages window when
used within a stored procedure that is called by an HTTP web service:
declare header_name long varchar;
declare header_value long varchar;
set header_name = NULL;
SET header_name = NEXT_HTTP_RESPONSE_HEADER( header_name );
IF header_name IS NULL THEN
SET header_value = HTTP_RESPONSE_HEADER( header_name );
MESSAGE 'RESPONSE HEADER: ', header_name, '=', header_value TO CONSOLE;