A data schema, especially a data subschema in a relational data system. 关系数据系统中的数据模式,特别是子模式。
Subschema and view of Access under the multi-user 多用户下的ACCESS子模式及视图机制
Their characters are discussed and their applications in subschema query language are introduced. 最后,介绍了这些运算在关系数据库子模式查询语言VQL中的应用。
This limit the user's visit to the database table of Access only in subschema. It enhances the security coefficient of database and atonement the security problem of Access. 文章在Access2000中实现了限制有关用户只能使用子模式对数据表的访问,增加了数据库的安全系数,弥补了Access2000安全上的不足。
The Boolean operations of partial compatible relation and their application in subschema query language 部分相容关系的集合运算及其在数据库查询语言中的应用
The thesis expounds the structure of the traffic measure unit and makeup of subschema. 详细阐述了流量计量单元的总体结构与子模块组成。