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Anonymous users2024-02-07Answer]: This question tests the basic knowledge of object-oriented databases. The characteristics of the database depend on the practical application, and the database language must be designed to allow users to easily use these features, and the database structure should be able to support these features effectively.
As a new type of database system, the object-oriented database should have the following characteristics: the ability to express and manage objects, and the object-oriented database system describes the real world by repaying objects and the interconnections between them; The ability to represent the structure of complex objects should have the ability to express complex objects in the real world; The ability to express and manage database changes, the ability to manage multiple versions of the same object is critical for design and engineering applications; The ability to express nested objects is an important feature of object orientation.
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Anonymous users2024-02-06Facing the BAI image database is a database schema DU, and both Oracle and PostgreSQL have DU
Yes, there is this feature. The advantages are as follows: DAO
1. Easy to maintain.
The structure of the object-oriented design capacity is adopted, the readability is high, and due to the existence of inheritance, even if the requirements are changed, then the maintenance is only in the local module, so it is very convenient and low cost to maintain.
2. High quality.
At design time, it is possible to reuse existing, tested classes in the domain of previous projects to make the system meet business needs and have a high quality.
3. High efficiency.
In software development, real-world things are abstracted according to the needs of the design to produce classes. Using such a method to solve problems is close to daily life and natural ways of thinking, and is bound to improve the efficiency and quality of software development.
4. Easy to expand.
Due to the characteristics of inheritance, encapsulation, and polymorphism, a system structure with high cohesion and low coupling is naturally designed, which makes the system more flexible, easier to expand, and lower cost.
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Anonymous users2024-02-05Object-orientation is a kind of cognitive methodology, and it is also a new programming methodology.
At present, the commercial database management system is dominated by relational database, and the technology is relatively mature.
Although the object-oriented database management system is technologically advanced and the database is easy to develop and maintain, there is no mature product yet. The leading relational database management systems at home and abroad include Oracle, Sybase, Informix and Ingres. These products all support multiple platforms, such as UNIX, VMS, and Windows, but not to the same extent.
Their platform support capabilities are compared in the analysis below. ibm
DB2 is also a full-fledged relational database.
However, DB2 is embedded in IBM's Hengxian.
As Shengchang 400 series machines, only OS 400 operating system is supported.
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