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澳洲伊迪斯科文大学论文代写:对象数据库

复杂对象:它代表了定义一组相似对象的特性支持类的概念和类型。对象的安全属性和对同一消息的响应可以组合在一起形成一个类。与类定义的属性和方法有关,而不是单独针对每个对象。变量和表达式的类型有助于编译时类型检查,检查程序的正确性。
对象:对象的身份认同是一个唯一标识每个对象的对象,不管它的内容;即使所有的属性都是相同的,对象有不同的OIDs。一个对象由两个组件组成,即属性和方法。定义对象特性的数据称为属性。此类数据的示例包括整数、字符串和实数,也可以是复杂对象引用。被称为过程或函数的对象的行为称为方法。它允许属性存储对其他元组的引用。使用不同的方法定义表中唯一标识的行类型和行之间的关系。实际的OID值对用户是不可见的,无法查询。
类型和类:面向对象的模型具有强大的类型系统,它有原始类型,如整数、字符串、日期和布尔等。结构类型是可以用模式记录的属性。集合类型是一个属性,它可以是其他类型的集合、包、列表和数组。引用类型是可以指向另一类型的指针的属性。对象可以充当对象类中的模板。指定的结构是由实例的一组属性、一组操作和一组实现操作的方法组成的。

澳洲伊迪斯科文大学论文代写:对象数据库

Complex objects: It represents the concept and type of the feature support class that defines a set of similar objects. Security attributes of objects and respond to the same message can be combined together to form a class. Related to the properties and methods of the class definition, rather than individually for each object. Variables and the type of the expression helps in compile-time type checking, check the correctness of the program.
Object identity: Object identity is a unique identity of each object objects regardless of its contents; even if all attributes are the same, objects have different OIDs. An object is made of two components i.e. the attributes and the methods. The data with which the characteristics of an object are defined is known as Attributes. The examples of this kind of data include integers, strings, and real numbers and it can also be complex objects reference. The behavior of an object which is formally also known as procedures or functions are termed as Methods. It allows attributes to store a reference to other tuples. The relationships between types of rows and a row that is uniquely identified in a table are defined by using various methods. The actual OID values are not visible to users and cannot be queried.
Types and classes: The object-oriented model has powerful type system and it has primitive types such as integer, string, date and Boolean etc. Structure types are the attributes that can be recorded with a schema. Collection types are the attribute that can be a set, bag, list, and array of other types. Reference types are the attributes that can be a pointer to another type. An object can act as template in the object class. The structure is specified which is made up of the set of attributes of the instances, a set of operations and set of methods through which the operations are implemented.