中文摘要：

内存数据库是外存数据库的“工作版本”，它们无论在数据上、结构上等都应该保持一致性。怎么定义内存数据库的存储结构，特别当外存数据库中表的结构发生改变时，内存数据库中表结构的相应改变，都直接影响系统的性能。研讨了内存数据库结构的定义以及实现，并对静态和动态存储结构的机制作了详尽的分析，突出地反映了动态特性。

英文摘要：

MMDB （main-memory database） is ＂work edition＂ of storage database. They should keep consistency regardless on the data or on the structure. How to define structure of MMDB will directly influence the performance especially when their structures of storage database are changed. The definition and implementation about the structure of MMDB are discussed, and the mechanism of static and dynamic storage structure are analyzed in detail, its dynamic characteristic is shown.