Chapter 1 Notes - Summary Fundamentals of Database Systems PDF

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Key points from chapter 1 of the textbook...

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Definitions: 1. Data: Raw facts, or facts that have not been processed to reveal their meaning to the end user. 2. Database: A shared, integrated computer structure that houses a collection of related data. Contains two types of data: end-user data (raw facts) and metadata 3. DBMS (Database Management System): Manages the data, provides security, a means of accessing data from in the database. 4. Database System: An organization of components that defines and regulates the collection, storage, management, and use of data in a database environment. 5. Database Catalog: Consists of metadata in which definitions of database objects are stored -such as base tables, views (virtual tables), synonyms, value ranges, indexes, users, and user groups. 6. Program-data Independence: The separation of the logical (conceptually organizes and understands data) and physical views (how and where the data are physically arranged and stored on a disk, tape, or other media) of data 7. User View: Subset of the database that contains virtual data derived from the database files but is not explicitly stored. 8. Database Administrator (DBA): Job title focused on directing, performing, or overseeing activities associated with a database or set of databases. 9. End User: A person or system that directly interacts with the solution. 10. Canned Transaction: Standard types of queries and updates that have been carefully programmed and tested. Mostly used by naive users to perform actions on the database related to their needs. 11. Deductive Database System: Provides capabilities for defining deduction rules; inferencing new information from the stored database facts. 12. Persistent Object: a specialized object that has the property of continuous state, which means it is available at all times. 13. Meta-data: Data associated with an object, supplementing the object’s file system data. 14. Transaction-processing application: A management information system designed to handle large volumes of routine, recurring transactions. 15. 4 Main Types of Database Actions: a. Selection b. Updating c. Deleting d. Inserting

Question Pool for Quiz: ● Data: Raw facts, or facts that have not been processed to reveal their meaning to the end user. ● Database: A shared, integrated computer structure that houses a collection of related data. Contains two types of data: end-user data (raw facts) and metadata. ● DBMS (Database Management System): Manages the data, provides security, a means of accessing data from in the database. ● Database System: An organization of components that defines and regulates the collection, storage, management, and use of data in a database environment. ● Meta-data: Data associated with an object, supplementing the object’s file system data. ● Data Abstraction: Data abstraction generally refers to the suppression of details of data organization and storage, and the highlighting of the essential features for an improved understanding of data. One of the main characteristics of the database approach is to support data abstraction so that different users can perceive data at their preferred level of detail ● Question 1.3: Discuss the main characteristics of the database approach and how it differs from traditional file systems. ○ DATABASE: ■ Self-describing nature of a database system ■ Insulation between programs and data, and data abstraction ■ Support of multiple views of the data ■ Sharing of data and multi-user transaction processing ○ FILE SYSTEM: ■ • Approach to the file system, each user is defined as necessary to implement the file, to perform a specific application ● Question 1.4: What are the responsibilities of the DBA and the database designers? ○ DBA focuses directing, performing, and overseeing activities associated with a database. ○ Database designers are responsible for identifying the data to be stored in the database and for choosing appropriate structures to represent and store this data. ● Question 1.5: What are the different types of database end users? Discuss the main activities of each. ○ Casual End Users: People who use a database query language to access a database, but do not develop applications. ○ Naive End Users: Constantly querying and updating the database, using standard types of queries and updates that have been

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carefully programmed and tested. ○ Sophisticated End Users: Engineers, scientists, etc who are experts at using the DB, and develop applications on top of a database. ○ Standalone End Users: Maintain personal databases by using readymade program packages that provide easy-to-use interfaces. Question 1.12: Cite some examples of integrity constraints that you think can apply to the database shown in Figure 1.2. ○ Question 1.14a: Consider Figure 1.2. a. If the name of the ‘CS’ (Computer Science) Department changes to ‘CSSE’ (Computer Science and Software Engineering) Department and the corresponding prefix for the course number also changes, identify the columns in the database that would need to be updated. ○ Within the Student Table, Major needs updated ○ Within the Course Table, Course_number and Department will need updated ○ Within Section Table, Course_number will need updated ○ Within Prerequisite Table, Course_number and Prerequisite_number will need updated...