DATA RESOURCE MANAGEMENT Chapter5 DATA RESOURCE MANAGEMENT

Content Technical Foundations of Database Management Fundamental Data Concepts Database Structures Database Development Managing Data Resources Types of Databases Data Warehouses and Data Mining Traditional File Processing The Database Management Approach

Database Management Data is difficult to retrieve if it was stored in unorganized way. In all information systems, data resources must be organized and structured in some logical manner so that they can be accessed easily, processed efficiently, retrieved quickly, and managed effectively. Data structures and access methods ranging from simple to complex have been devised to organize and access data stored by information systems efficiently.

Fundamental Data Concepts Data may be logically organized into: Characters: It consists of a single alphabetic, numeric, or other symbol. Fields(data item): A field consists of a grouping of related characters to represent attribute( characteristic or quality) of entity. Ex: lastname, firstname. Records: A record represents a collection of attributes that describe a single instance of an entity .Ex: person’s payroll record. Files: A group of related records(Single table = flat file) Databases: A database is an integrated collection of logically related data elements. It contains data elements describing entities and relationships among entities.

Fundamental Data Concepts The examples of how data fields, records, files, and databases relate. The business applications that access the data in the database

Database Structures The relationships among the many individual data elements stored in databases are based on one of several logical data structures, or models. Database management system (DBMS) packages are designed to use a specific data structure to provide end users with quick, easy access to information stored in databases. There are five database structures(Model): Hierarchical: All records are dependent and arranged in multilevel structures, consisting of one root record and any number of subordinate levels(one to many).It was used by Early mainframe DBMS packages. Network: It allows many-to-many relationships among records. It was used by some mainframe DBMS packages. Relational: All data elements within the database are viewed as being stored in the form of simple two-dimensional tables. Three basic operations can be performed on a relational database to create useful sets of data(select, join, project). It is used by most microcomputer DBMS packages, Midrange, and Mainframe. object-oriented: It was encapsulation data(Attribute) and Operation in single unit. Object Oriented operation is inheritance. Popular in computer-aided design(CAD) Multidimensional: It is a variation of the relational model that uses multidimensional structures to organize data and express the relationships between data(cubes of data). multidimensional databases have become the most popular database structure for the analytical databases that support online analytical processing (OLAP) applications

Database Structures

Database Structures

Database Development Database management packages like Microsoft Access or Lotus Approach allow end users to develop the databases they need easily. Tools for develop database: Data definition language (DDL): It is used to develop and specify the data contents, relationships, and structure of each database. Data Planning and Database Design Data planning process(Enterprise Model and Data Modeling): Database administrators and designers work with corporate and end-user management to develop an enterprise model that defines the basic business process of the enterprise. They then define the information needs of end users in a business process. Next, end users must identify the key data elements that are needed to perform their specific business(ERD) activities. Data Model=Logical Design, Physical Design.

Database Development

Example of the logical and physical database views and the software interface of a banking services information system

Types of Databases Operational databases store detailed data needed to support the business processes and operations of a company. They are also called subject area databases (SADB), transaction databases , and production databases. Ex human resource database, inventory database Distributed Databases may be copies of operational or analytical databases, hypermedia or discussion databases, or any other type of database. Replication and distribution of databases improve database performance at end-user worksites. External Databases is available for a fee from commercial online services and with or without charge from many sources on the World Wide Web(Result of search engine). Hypermedia Databases consisting of hyperlinked pages of multimedia (text, graphic and photographic images, video clips, audio segments, and so on).

Types of Databases

Types of Databases

Data Warehouses and Data Mining Data warehouse stores data that have been extracted from the various operational, external, and other databases of an organization. It is a central source of the data that have been cleaned, transformed, and cataloged so that they can be used by managers and other business professionals for data mining, online analytical processing, and other forms of business analysis, market research, and decision support. Data warehouses may be subdivided into data marts , which hold subsets of data from the warehouse that focus on specific aspects of a company, such as a department or a business process. Data in a data warehouse are static , which means that once the data are gathered up, formatted for storage, and stored in the data warehouse, they will never change. Feature of Data Mining: It use of data warehouse databases and the static data they contain. The data in a data warehouse are analyzed to reveal hidden patterns and trends in historical business activity(help managers make decisions about strategic changes in business operations to gain competitive advantages in the marketplace). Many companies use data mining to: Perform market-basket analysis to identify new product bundles. Find root causes of quality or manufacturing problems. Prevent customer attrition and acquire new customers. Cross-sell to existing customers. Profile customers with more accuracy.

The components of a complete data warehouse system

Data warehouse get data from external source

How data mining extracts business knowledge from a data warehouse

Traditional File Processing Problems of File Processing: Data Redundancy: The same data (such as a customer’s name and address) were recorded and stored in several files. It caused problems when data had to be updated or maintained. Lack of Data Integration Data Dependence Lack of Data Integrity or Standardization

The Database Management Approach Database Management System (DBMS) is the main software tool of the database management approach because it controls the creation, maintenance, and use of the databases of an organization and its end users. A database interrogation capability is a major benefit of the database management approach. End users can use a DBMS by asking for information from a database using a query feature or a report generator . Database maintenance process is accomplished by transaction processing systems and other end-user applications, with the support of the DBMS. Application Development End users, systems analysts, and other application developers can use the internal 4GL programming language and built-in software development tools provided by many DBMS packages to develop custom application programs.