查询大数据表的效率对比：Linq to SQL、Entity Framework、企业(10)

                        if ((parameter.Direction == ParameterDirection.InputOutput || parameter.Direction == ParameterDirection.Input) &&
                            (parameter.Value == null))
                        {
                            parameter.Value = DBNull.Value;
                        }
                        command.Parameters.Add(parameter);
                    }
                }
            }

            return command;
        }

    }
}

 

摘自  昕友