This paper inquires about the system daily book of actual need, through to the C/S mode, PowerBuilder6.5 development tools, database and the SQL language into learning and practice, mainly completed the LAN books data inquires the the demand analysis of the system, database design, application design work. First of all, in the introduction section describes the LAN books information query system application background, development environment and the selection of development tools and databases, expounds the relationship between the concept of local area network. The beginning of the second chapter introduces the basic concept of a relational database, the focus on a few key definition of the concept. Chapter 3 from the characteristic and function of, this paper introduces the development tools PowerBuilder6.5; And introduces the C/S mode the concept, characteristic and the C/S mode and development tools PowerBuilder6.5 contact ?
关键词：C/S structure, LAN, database, SQL language, PowerBuilder6.5