Describe the various types of databases used by organizations and end-users.
Describe the various types of databases used by organizations and end-users.
Ans.
Types of Databases
The growth of distributed processing, end user computing, decision support and executive information systems has caused the development of several types of databases; some of these are discussed as under:
(i) Management Databases. These databases store data and information extracted from selected operational and external databases. They consist of summarized data and information most needed by the organization’s managers and other end users. Such databases are accessed by executive users as part of decision support systems and executive information systems to support managerial decision making.
(a) It is created to meet information requirements for middle-level management also known as tactical level. Such systems which help us to produce information to be used for decision-making process is known as MIS.
(b) Its objective is to help the managers to carry out various functions such as planning, organizing, staffing, directing and controlling.
(c) The middle-level managers need (1) internal information which can be created by logically relating different physical databases at the operational level (2) external information from the other organizations, e.g., pricing policy of a competitor or import/export policy of the government, etc.
(ii) Operational Databases. These databases also known as subject area database (SADB), transaction databases and production databases store detailed data needed to support the operations of the entire organization. It deals with meeting the requirements of operational level of management.
(a) The main objectives are (1) collection of data, (2) storage of data, (3) retrieval of data, and (4) processing of data to generate information to be used during the design of MIS.
(b) Separate databases are created for each function within the organization, e.g., (1) finance, (2) inventory, (3) production, (4) marketing, etc.
(iii) End User Databases. These databases consist of a variety of data files developed by end users at their workstations.
(a) The end users are senior executives, i.e., top level of management.
(b) For each user menus are created during the design of external implementation of a database.
(c) Each user can create an additional database for keeping such data which is exclusively required for his own function. It may contain (1) electronic mails received from others, (2) spreadsheet containing data arranged in the form of a table, and (3) word processing documents, e.g., various letters written by the user, etc.
(iv) Distributed Databases. These are databases of local work groups and departments at regional offices, branch offices, manufacturing plants and other work site, which can include segments of both common operational and common user databases as well as data generated and used only at a user’s own site.
(a) It is a technique by which databases can be divided into multiple files so that separate databases can be physically created at different branch offices but logically connected to a single database with the help of defining pointers (links).
(b) It facilitates accessing the data from any location, e.g., data of a branch office can be accessed from the head office or vice-versa.
(c) Based upon the receipt of a transaction, all relevant databases can be simultaneously updated.
(d) It is best achieved with the help of relational database structure.
(v) External Databases. Access to external, privately owned online databases or databanks is available, for a fee, to end users and organizations from commercial information services.
(a) Any organization needs data from external sources during the design of (1) DSS, (2) EIS, and (3) ES.
(b) These databases may be in the form of (1) technical database giving specifications of various materials and services which are being purchased by the organization, (2) commercial database giving pricing details and other terms and conditions, (3) abstracts taken from various newspapers and technical magazines, etc.
(c) Most of these databases are privately owned which can be accessed either free of charge or at prescribed rates.
(vi) Analytical Databases. These databases also called multi dimensional databases. They store data and information extracted from selected operations and external databases. They consist of summarized data and information most needed by a manager and other end users in the organization and are accessed by the online analytical processing systems, decision support systems and execute information systems.
(vii) Text Databases. Text databases are a natural outgrowth of the use of computers to create and store documents electronically. Thus, online databases services store bibliographic information such as publications in large text databases. Text databases are also available on CD-ROM optical disks for use with microcomputer systems. Major corporations and government agencies have developed large text databases containing documents of all kinds. They use text databases management system software to help, create, store, search, retrieve, modify, and assemble documents and other information stored as text data in such databases.
