【摘要】 针对工程数据库管理系统的实际需求,在设计实现基于Web的工程数据库管理系统EDBMS的SQL语言系统时,提出了一种以逻辑分层为基础的系统开发模式——虚拟机模式。该模式由Web Server将用户在浏览器端输入请求命令组装成标准SQL语句,并将这些语句传递给解释器,由解释器进行词法分析、语法分析和错误检查后生成底层EDBMSAPI能够执行的命令序列,从而实现了对数据库的操作。更多还原

【Abstract】 In view of the demand for EDBMS,this paper puts forword a system exploitation model——database virtual machine model that can be used for the design and implement of EDBMS basede on web.In this model,Web Server would package all request message into standard sql statement,and pass this statement on to interpreter.The interpreter takes charge of the lexical analysis syntax、analysis and error-checking,and then generates EDBMS API that can executive command,thus the operation of database was implemented.更多还原