獭兔吧,江西省抚州市区号,mop
1.马克斯·C的简介 1. Introduction of Max C
马克斯·C是一个伦敦品牌，与配件和服装领域的摄影原作和小说故事的发展有着紧密联系。拥有国际化的设计团队,品牌的创建依靠独家收集来的不同城市的灵魂和灵感。马克斯·C品牌每季都会创建一个独具特色特点的产品，混合特殊形状，吸收全球魅力，使这个品牌发展得越来越强大。马克斯·C主要经营女士服装、包、皮带等。此外，马克斯·C还提供批发供应服务，为了更好地管理整个批发商的数据，他们决定创建数据库,他们也听过许多数据库系统，例如RDBMS数据库系统和对象关系数据库系统和。
他们想知道所有的数据库管理系统,数据库系统的优化能够带来巨大便捷。所以,我们应该极力提供一个良好的数据库系统。 数据库管理系统的定义 §使用户能够对数据库的访问进行定义、创建、维护和控制。 §收集数据库结构的程序管理，控制对数据的访问。 §可以在多个应用程序或用户之间共享数据。
§使数据管理更有效率，更有效。
Max C is a London brand linked with its development of original prints and novel cuts in both accessories and clothing. With a cosmopolitan design team, the brand creates exclusive collections from the heart of a diverse city. Moving from strength to strength, Max C is a brand producing fresh remarkable shapes each season that blend the exceptional with global charm. It's mainly deals with ladies garments, bags, belts etc. Max C supplies the wholesale for all the things, to manage the data of the entire wholesaler they decided to make database, and also they heard it about many database system like RDBMS, ORDBMS and OODBMS.
They want to know about all the DBMS and which database system is better we prefer them. So keeping in mind that we are providing a good database system. Definition of Database Management System (DBMS) DBMS: § Enables users to define, create, maintain, and control access to the database. § Collection of programs that manages database structure and controls access to data § Possible to share data among multiple applications or users
§ Makes data management more efficient and effective DBMS Function: Performs functions that guarantee integrity and consistency of data - Data dictionary management defines data elements and their relationships - Data storage management Stores data and related data entry forms, report definitions, etc. - Data transformation and presentation translates logical requests into commands to physically locate and retrieve the requested data - Security management enforces user security and data privacy within database - Multi-user access control creates structures that allow multiple users to access the data - Backup and recovery management provides backup and data recovery procedures - Data integrity management promotes and enforces integrity rules to eliminate data integrity problems - Database access languages and application programming interfaces provides data access through a query language - Database communication interfaces
allows database to accept end-user requests within a computer network environment 2. Types of DBMS Relational- RDBMS Object Relational- ORDBMS Object Oriented - OODBMS Hierarchical Network We have five types of DBMS but we are mainly discussing here about three DBMS. RDBMS ORDBMS
OODBMS I. RDBMS: RDMBS MODEL CHARACTERISTICS OF RDBMS Eliminates parent chain relationship and represents data in database. The data is organized into rows and columns, forming tables. Rows of the database tables are called tuple and columns are called attributes. The data can be easily manipulated and transformed. Example of rdbms: MS SQL Server, Oracle, MySQL, MS Access, SyBase, II. ORDBMS CHARACTERISTICS OF ORDBMS: III. OODBMS ADVANTAGES OF RDBMS Advantages - Structural independence - Improved conceptual simplicity - Easier database design, implementation, management, and use - Ad hoc query capability - Powerful database management system Disadvantages - Substantial hardware and system software overhead - Can facilitate poor design and implementation - May promote “islands of information” problems DISADVANTAGE licenses is expensive need software and hardware (as it is heavy) need professionals to deal with it proper traninig is required Its fast acurate, standard way to store data on permanent basis extraction of data is done using SQL its secure (different level of security) data can be managed in proper manner. ACID properties are features if RDBMS stands for Accuracy Consitency Isolation Durability
all these things are done using locks, transaction management, prallel query processing, etc I have seen that for web applications is best far using a ODBMS:
1- Objects in an OODBMS can store an arbitrary number of atomic types as well as other objects. The fact that an OODBMS is better suited to handling complex,interrelated data than an RDBMS means that an OODBMS can outperform an RDBMS by ten to a thousand times depending on the complexity of the data being handled.
2- Data in the real world is usually has hierarchical characteristics. The ever popular Employee example used in most RDBMS texts is easier to describe in an OODBMS than in an RDBMS.
3- A query language is not necessary for accessing data from an OODBMS unlike an RDBMS since interaction with the database is done by transparently accessing objects. It is still possible to use queries in an OODBMS however.
4- In a typical application that uses an object oriented programming language and an RDBMS, a signifcant amount of time is usually spent mapping tables to objects and back. This "impedance mismatch" is completely avoided when using an OODBMS.
5- The user of an RDBMS has to worry about uniquely identifying tuples by their values and making sure that no two tuples have the same primary key values to avoid error conditions.
6- With an RDBMS it is not possible to model the dynamic operations or rules that change the state of the data in the system because this is beyond the scope of the database. With an OODBMS there is no disconnect between the database model and the application model because the entities are just other objects in the system. The main elements of RDBMS are based on Ted Codd's 13 rules for a relational system, the concept of relational integrity, and normalization.
The system was originally created to handle the integration of media, traditional fielded data, and templates. Another limitation of the relational database is its inadequacy to operate with languages outside of SQL. After its original development, languages such as C++ and JavaScript were formed. However, relational databases do not work efficiently with these languages. A third limitation is the requirement that information must be in tables where relationships between entities are defined by values. Today, the relational model is the dominant data model as well as the foundation for the leading DBMS products, which include IBM's DB2 family, Informix, Oracle, Sybase, Microsoft's Access and SQLServer, as well as FoxBase and Paradox. RDBMS represent close to a multibillion-dollar industry alone. Next: Object-Oriented Database Management System >> |
