基于非一致性数据库的概率查询策略与算法

完整性约束是保证关系型数据库中数据确定性的重要条件，现实中存在大量不确定、不满足完整约束条件，但仍具有使用价值。结合概率数据库理论，提出了一种新的针对非一致性数据库的查询策略，利用并、交、差、选择、投影、连接等约束方法，对非一致性数据进行修复，四元组概率计算方法和概率查询重写技术弥补了非一致性数据库查询的不足，减少了数据冲突的发生机率。

Strategy and Algorithm of Probabilistic Query Based on Inconsistent Database

Integrity constraint is important to make data certain in relation database, but there is a larger amount of uncertain and inconsistent information that is valuable and useable. Combined with probabilistic database theory, this paper gives a new query plan aiming at inconsistent database. It uses the constraint methods including union, product, subtraction, selection, projection and link to repair inconsistent data effectively. Its probabilistic calculation with four elements and probabilistic query rewriting can overcome shortcomings of inconsistent databases and decrease conflict of data.