c# - Can't insert simple row into DB2 w/ EF5 -

i'm using ef5 , db2 9.1 z/os , ibm data provider. in program works fine except 1 part. can't insert new object database. error:

{"error [23502] [ibm][db2] sql0407n assignment of null value not null column \"empl_id\" not allowed."}

i have verified time after time value not null... it's valid integer. what's going on?

if (string.isnullorempty(emplid))             return null;         try         {             int _emplid = convert.toint32(emplid.trim());              using (var ctx = new data.timscontext())             {                 var user = (from u in ctx.query<data.entities.asnuser>()                             u.employeeid == _emplid                             select u).firstordefault();                 if (user == null)                 {                     //add user database                     user = new data.entities.asnuser()                     {                         employeeid = _emplid,                         firstname = firstname.trim(),                         lastname = lastname.trim()                     };                     ctx.set<data.entities.asnuser>().add(user);                     ctx.savechanges();                 }                  return new models.userinfo()                 {                     employeeid = user.employeeid,                     displayname = string.format("{0}, {1}", user.lastname, user.firstname)                 };             }         }         catch (exception e)         {             throw;         } 

the problem was setting user new object , adding dbset. guess created 2 distinct copies of user object, 1 null , 1 filled out. commented out add line , worked fine.