摘要：第一范式：列是原子的。第二范式：非主键列必须完全函数依赖所有主键列或候选主键列。第三范式：外键表只包含外键，不要重复主键表的其他列。 阅读全文

摘要：An OLTP scenario is characterized by a large number of concurrent operations that create, update, and delete data, packaged up as transactions. Most m... 阅读全文