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بسم الله الرحمن الرحيم. إعداد الطالب ::- ضياء أبو رجيلة. Data Resource Management. Data Resource Management. The definition of DataBase:- An Integrated collection of logically related data elements. Foundation Data Concepts (continued). Levels of data Character
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بسم الله الرحمن الرحيم • إعداد الطالب ::- • ضياء أبو رجيلة
Data Resource Management • The definition of DataBase:- An Integrated collection of logically related data elements.
Foundation Data Concepts (continued) • Levels of data • Character • Single alphabetical, numeric, or other symbol • Field • Groupings of characters • Represents an attribute of some entity
Foundation Data Concepts (continued) • Records • Related fields of data • Collection of attributes that describe an entity • Fixed-length or variable-length
Foundation Data Concepts (continued) • Files (table) • A group of related records • Classified by • Primary use • Type of data • permanence
Foundation Data Concepts (continued) • Database • Integrated collection of logically related data elements • Consolidates records into a common pool of data elements • Data is independent of the application program using them and type of storage device
Types of Databases • Operational • Supports business processes and operations • Also called subject-area databases, transaction databases, and production databases
Types of Databases (continued) • Distributed • Replicated and distributed copies or parts of databases on network servers at a variety of sites. • Done to improve database performance and security
Types of Databases (continued) • External • Available for a fee from commercial sources or with or without charge on the Internet or World Wide Web • Hypermedia • Hyperlinked pages of multimedia
Data Warehouses and Data Mining • Data warehouse • Stores data extracted from operational, external, or other databases of an organization • Central source of “structured” data • May be subdivided into data marts
Data Warehouses and Data Mining (continued) • Data mining • A major use of data warehouse databases • Data is analyzed to reveal hidden correlations, patterns, and trends
Database Management Approach • Consolidates data records and objects into databases that can be accessed by many different application programs
Database Management Approach (continued) • Database Management System • Software interface between users and databases • Controls creation, maintenance, and use of the database
Database Management Approach (continued) • Database Interrogation • Query • Supports ad hoc requests • Tells the software how you want to organize the data • SQL queries • Graphical (GUI) & natural queries
Database Management Approach (continued) • Report Generator • Turns results of query into a useable report • Database Maintenance • Updating and correcting data
Database Management Approach (continued) • Application Development • Data manipulation language • Data entry screens, forms, reports, or web pages
Implementing Data Resource Management • Database Administration • Develop and maintain the data dictionary • Design and monitor performance of databases • Enforce database use and security standards
Implementing Data Resource Management (continued) • Data Planning • Corporate planning and analysis function • Developing the overall data architecture
Implementing Data Resource Management (continued) • Data Administration • Standardize collection, storage, and dissemination of data to end users • Focused on supporting business processes and strategic business objectives • May include developing policy and setting standards
Implementing Data Resource Management (continued) • Challenges • Technologically complex • Vast amounts of data • Vulnerability to fraud, errors, and failures
Section II • Technical Foundations of Database Management
Database Structures • Hierarchical • Treelike • One-to-many relationship • Used for structured, routine types of transaction processing
Database Structures (continued) • Network • More complex • Many-to-many relationship • More flexible but doesn’t support ad hoc requests well
Database Structures (continued) • Relational • Data elements stored in simple tables • Can link data elements from various tables • Very supportive of ad hoc requests but slower at processing large amounts of data than hierarchical or network models
Database Structures (continued) • Multi-Dimensional • A variation of the relational model • Cubes of data and cubes within cubes • Popular for online analytical processing (OLAP) applications
Database Structures (continued) • Object-oriented • Key technology of multimedia web-based applications • Good for complex, high-volume applications
Accessing Databases • Key fields (primary key) • A field unique to each record so it can be distinguished from all other records in a table
Accessing Databases (continued) • Sequential access • Data is stored and accessed in a sequence according to a key field • Good for periodic processing of a large volume of data, but updating with new transactions can be troublesome
Accessing Databases (continued) • Direct access • Methods • Key transformation • Index • Indexed sequential access
Database Development • Data dictionary • Directory containing metadata (data about data) • Structure • Data elements • Interrelationships • Information regarding access and use • Maintenance & security issues
Database Development (continued) • Data Planning & Database Design • Planning & Design Process • Enterprise model • Entity relationship diagrams (ERDs) • Data modeling • Develop logical framework for the physical design