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Data Resource Management - Coggle Diagram
Data Resource Management
Technical Foundation of Database Management
Multiple Sources of Data
Internal Sources - Corporate databases, company documents
Personal Sources - personal thoughts, opinions, experiences
External Sources - commerical databases, government reports, and corporate web sites.
Fundamental Data Concepts
Character - the most basic logical data ellement that can be observed, a single alpha or numeric or other symbol, represented by one byte
Field - a grouping of related characters, as a last name or salary, represents an attribute of some entity general purpose
Record - a grouping of attributes that describe an entity
File - a group of related data records
Database - a collection of logically related data elements
Database Structure (Models)
Hierarchical Structure – treelike structure of one-to-many parent-child relationships (each child can have only one parent)
Network Structure – similar to hierarchical but allows many-to-many relationships (a child record can have more than one parent)
Relational Structure – the most widely used database model today; data is represented as a series of two-dimensional tables called Relations; each column is a named attribute of the entity, each row is an unnamed instance of that entity
Relational Operations
Select – create a subset that meets a criterion
Join – temporarily combine two or more tables for comparison
Project – create a subset of the columns in the temporary tables
Multidimensional Structure
Database Development
Database Administrator (DBA) – controls development and administration of the database
Data Definition Language (DDL) – used to specify the contents, relationships, and structure of the database
Data Dictionary – directory containing the metadata
Data Planning dan Database Design
Managing Data Resources
Types of Databases
Operational Databases – store detailed data to support business processes and operations
External Databases – outside the firm, free or fee-based
Distributed Databases – many organizations distribute their databases over multiple locations
Data Warehouse and Data Mining
Data Warehouse – stores data extracted from other databases
Data Mart – subset of a data warehouse focusing on a single topic, customer, product, etc.
Data Mining – analyzing a data warehouse to reveal hidden patterns and trends
Problems of File Processing – databases seek to solve these problems
Data Redundancy – the same data is kept in more than one location; databases seek to Control (NOT reduce!) Redundancy; this led to Data Inconsistency – same data in multiple locations but the Values were Different
Lack of data Integration – data not easily available for ad hoc requests
Data Dependence – data and programs were “tightly coupled”, changing one meant having to change the other
Lack of Data Integrity (Standardization) – data was defined differently by different end users or applications
Database Management Approach
Database Management System (DBMS) – a collection of programs to create, maintain, and use (retrieve) data in a database
Database Maintenance – organizational databases need to be updated continually
Application Development – facilitated by the Data Manipulation Language (DML) provided by the DBMS