Week 4 - Hardware, Software, Database Processing, Database Design Flashcards
(12 cards)
What Do Business Professionals Need To Know About Software - Categories
● Horizontal-market applications → Provide capabilities common across all organizations and
industries (e.g., Microsoft Office, Browser) → off-the-shelf
● Vertical-market applications → Serve the needs of a specific industry (e.g., Canvas, ATM system,
airline booking system) → off-the-shelf and then customized
● One-of-a-kind applications → Developed for a specific, unique need (e.g., National military
system) → custom developed
purpose of a database
Organize and keep track of different kinds of data e.g., Customer data, sales data, HR data, and Accounting records
what is a database
Self-describing collection of integrated records
components of a database
→ makes database more meaningful, e.g. table of customer personal data linked with a table of the sales
transaction, what kind of analysis you can perform?
Tables or Files + Relationships Among Rows in Tables + Metadata = Database
primary key, foreign key, and relationships
Primary key = a column or a group of columns that uniquely identifies a row in a table (every table
must have a PK)
Future key = primary key that appears in another table to create a relationship/link (not all tables
have foreign keys)
Primary key and foreign key enable the linkage among tables
Database Management System
A program to create, process, and administer a database
User → Database application (forms, reports, queries, applications, programs) → DBMS (Database
management system) → Database (Tables, Relationships, Metadata)
4 DBMS Operations
- Read → read/extract student info
- Insert → add new student record
- Modify → change tutorial class
- Delete data → drop/withdraw a student
Structured Query Language (SQL)
International standards to communicate with relational databases and used by most popular DBMS
E.g., Select SID, Name, and Score from the Test
How Do Database Applications Make Databases More Useful?
Database → Store data and relationships
DBMS → Handle operations of data
Database application → Usually tailor-made for different purposes
What Are the Components of the Entity-Relationship Data Model?
Entities (table):
● Something users want to track
● E.g., Order, customer, salesperson, item, volunteer, donation
Attributes (fields):
● Describe the characteristics of an entity
● E.g., Order number, Customer number, Volunteer name, Phone number
Identifier (primary key):
● Uniquely identify one entity instance from another instance
● Student_ID_Number
How Is a Data Model Transformed into a Database Design - normalization - data integrity problems
Normalization
● Converting poorly structured tables into two or more well-structured tables
● Goal: Construct tables with data about a single theme or entity
● Purpose: To minimize data integrity problems
Data Integrity Problems
● Produce incorrect and inconsistent information, users lose confidence in information, and the
system gets a poor reputation
● This can only occur if data are duplicated
summary of normalization
Summary of Normalization
● One of the criteria for evaluating database designs
● Can be slower to process (limitation)
● Designers sometimes choose to accept non-normalized tables
● The best design of a table depends on how well it meets the users’ requirements
