XSODATA CRUD Operations (Update using not working)

Question

this one works:
service namespace "My.Service" {   
   "Schema"."Package::Table" as "Table" keys generate local "ID"
          create using "Package::SP_MySP";
this one doesn't work:
service namespace "My.Service" {   
   "Schema"."Package::Table" as "Table" keys generate local "ID"
          update using "Package::SP_MySP";
I am getting a syntax error on the update using statement in the odata service definition.

Answer 1

key field means unique record.
if u try to change a key field it will add a new entry.
to an existing entry with a key combination u can change only the non-key fields.
else u need to delete the record combination and add the new combination.