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Introduction and Conceptual Modeling

Sophisticated : these include business analysts, scientists, engineers, others thoroughly familiar with the system capabilities. Many use tools in the form of software packages that work closely with the stored database. Stand-alone : mostly maintain personal databases using ready-to-use packaged applications. An example is a tax program user that creates his or her own internal database. | Introduction and Conceptual Modeling Types of Databases and Database Applications Numeric and Textual Databases Multimedia Databases Geographic Information Systems (GIS) Data Warehouses Real-time and Active Databases Basic Definitions Database: A collection of related data. Data: Known facts that can be recorded and have an implicit meaning. Mini-world: Some part of the real world about which data is stored in a database. For example, student grades and transcripts at a university. Database Management System (DBMS): A software package/ system to facilitate the creation and maintenance of a computerized database. Database System: The DBMS software together with the data itself. Sometimes, the applications are also included. Typical DBMS Functionality Define a database : in terms of data types, structures and constraints Construct or Load the Database on a secondary storage medium Manipulating the database : querying, generating reports, insertions, deletions and modifications to its . | Introduction and Conceptual Modeling Types of Databases and Database Applications Numeric and Textual Databases Multimedia Databases Geographic Information Systems (GIS) Data Warehouses Real-time and Active Databases Basic Definitions Database: A collection of related data. Data: Known facts that can be recorded and have an implicit meaning. Mini-world: Some part of the real world about which data is stored in a database. For example, student grades and transcripts at a university. Database Management System (DBMS): A software package/ system to facilitate the creation and maintenance of a computerized database. Database System: The DBMS software together with the data itself. Sometimes, the applications are also included. Typical DBMS Functionality Define a database : in terms of data types, structures and constraints Construct or Load the Database on a secondary storage medium Manipulating the database : querying, generating reports, insertions, deletions and modifications to its content Concurrent Processing and Sharing by a set of users and programs – yet, keeping all data valid and consistent Typical DBMS Functionality Other features: Protection or Security measures to prevent unauthorized access “Active” processing to take internal actions on data Presentation and Visualization of data Example of a Database (with a Conceptual Data Model) Mini-world for the example: Part of a UNIVERSITY environment. Some mini-world entities: STUDENTs COURSEs SECTIONs (of COURSEs) (academic) DEPARTMENTs INSTRUCTORs Note: The above could be expressed in the ENTITY-RELATIONSHIP data model. Example of a Database (with a Conceptual Data Model) Some mini-world relationships: SECTIONs are of specific COURSEs STUDENTs take SECTIONs COURSEs have prerequisite COURSEs INSTRUCTORs teach SECTIONs COURSEs are offered by DEPARTMENTs STUDENTs major in DEPARTMENTs Note: The above could be expressed in the ENTITY-RELATIONSHIP data model. Main Characteristics of the Database Approach .