数据库的安全性和完整性是数据库安全保护的两个不同的方面。数据库的安全性

Database security and integrity are two different aspects of database security protection. The security of the database protects the database to prevent damage caused by illegal users, and the integrity of the database protects the database to prevent damage caused by unintentional users. From the perspective of database security protection, integrity and security are closely related. The basic synonym of the integrity of the database refers to the correctness, validity and compatibility of the data in the database, and its main purpose is to prevent erroneous data from entering the database. Correctness refers to the legality of data. For example, numeric data can only contain numbers but not letters. Validity refers to whether the data belongs to the valid range of the defined domain. Compatibility means that two data representing the same fact should be consistent, and inconsistency is inconsistency. The database system is a simulation of the real system. There are various rules and regulations in the real system to ensure the normal and orderly operation of the system. Many rules and regulations can be transformed into constraints on data. These semantic constraints added to the data are called database integrity constraints, referred to as "database integrity", the system "defines" it as part of the model in the DBMS. The DBMS must provide a mechanism to check the integrity of the data in the database to see if it meets the conditions specified by the semantics. This mechanism is called "integrity check". To this end, the integrity control mechanism of the database management system should have three functions to prevent legitimate users from injecting illegal or unsynchronized data into the database when using the database:

数据库的安全性和完整性是数据库安全保护的两个不同的方面。数据库的安全性保护数据库以防止不合法用户故意造成的破坏，数据库的完整性保护数据库以防止合法用户无意中造成的破坏。从数据库的安全保护角度来讲，完整性和安全性是密切相关的。数据库的完整性的基本合义是指数据库中数据的正确性、有效性和相容性，其主要目的是防止错误的数据进入数据库。正确性是指数据的合法性，例如数值型数据只能含有数字而不能含有字母。有效性是指数据是否属于所定义域的有效范围。相容性是指表示同一事实的两个数据应当一致，不一致即是不相容。数据库系统是对现实系统的模拟，现实系统中存在各种各样的规章制度，以保证系统正常、有序地运行。许多规章制度可转化为对数据的约束，这些添加在数据上的语义约束条件称为数据库完整性约束条件，简称“数据库的完整性”，系统将其作为模式的一部分“定义”于DBMS中。DBMS必须提供一种机制来检查数据库中数据的完整性，看其是否满足语义规定的条件,这种机制称为“完整性检查”。为此，数据库管理系统的完整性控制机制应具有三个方面的功能，来防止合法用户在使用数据库时，向数据库注入不合法或不合语义的数据:

Database security and integrity are two different aspects of database security protection. The security of the database protects the database from the damage caused by the illegal users. The integrity of the database protects the database from the damage caused by the legitimate users unintentionally. From the perspective of database security, integrity and security are closely related. The basic meaning of database integrity refers to the correctness, validity and compatibility of data in the database. Its main purpose is to prevent the wrong data from entering the database. Correctness refers to the validity of data. For example, numerical data can only contain numbers but not letters. Validity refers to whether the data belongs to the valid range of the defined domain. Consistency refers to that two data representing the same fact should be consistent, and inconsistency is incompatibility. The database system is a simulation of the real system. There are various rules and regulations in the real system to ensure the normal and orderly operation of the system. Many rules and regulations can be transformed into constraints on data. These semantic constraints added to data are called database integrity constraints, or "database integrity" for short, which are defined in DBMS as a part of the schema. DBMS must provide a mechanism to check the integrity of the data in the database to see if it meets the semantic requirements. This mechanism is called "integrity check". Therefore, the integrity control mechanism of database management system should have three functions to prevent legitimate users from injecting illegal or semantic data into the database when using the database:<br>