1 Single user DBS: The entire DBS includes applications, DBMS, and data are installed on a computer, by one user exclusive, and data cannot be shared between different machines.
The disadvantage is that there is a lot of redundant data;
2 The DBS of the main slave structure: refers to a multi-user structure with a host with multiple terminals. The entire DBS includes applications, DBMS, and data are stored in the host, all processing tasks are completed by the host, and each user passes through the host's terminal and sharing data resources.
Advantages: Simple, data is easy to manage and maintain;
Disadvantages: The host task is heavy, the number of users increases makes performance, and the host has failed, causing the system crash, reliability is not high;
3 Distributed DBS: The data in DB is logically a whole, but physically distributes on the different nodes of the computer network.
Main problems: Treatment, management, maintenance of data, difficult, remote data access results in system efficiency by network speed;
4 DBS of the client / server (C / S): In the C / S structure, the client's user request is transmitted to the database server, and the database server only returns the result to the user, reducing the data transfer on the network, improves The performance, throughput and load capacity of the system, while the database is more open, can run on a variety of platforms.
The DBMS of the C / S structure can be divided into a centralized server structure and distributed server structure.
