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Before we begin…. Introduce yourself. Do mention something about your educational and professional backgrounds. What are your goals for graduation? What do you want to do??. Unit 1: Database History, Models, and Structure. IT 390 - Business Database Administration.
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Before we begin… • Introduce yourself. Do mention something about your educational and professional backgrounds. • What are your goals for graduation? What do you want to do??
Unit 1: Database History, Models, and Structure IT 390 - Business Database Administration
Primary Lesson Objectives • Explain the history, basic models and components of databases. • Identify the importance of Relational Algebra, SQL, and ERD Diagrams.
More Details… • Identify the components of a database and their uses. • Define DBMS and RDBMS. • Identify the differences between DBMS and RDBMS. • Identify the features and functionality of RDBMS. • Identify the data models used for organizing data. • Identify the types of databases and their functionality. • Analyze the E-R data model. • Identify the object-oriented logical data model. • Explain the basic components of databases.
Databases: An Overview • Databases are organized collection of related data. • Databases can contain data of the following data types at a single location: • Text • Graphic • Audio • Video • An example is a Hotel which has a “guest” list with details about guest (room number, length of stay, mini-bar tab, etc.)
Features of a Database • A database has the following features: • Stores data in an organized manner. • Searches and retrieves the stored data. • Maintains a single copy of the data. • Provides security to the stored data. • Several corporations produce database software products. Two BIG players are Microsoft and Oracle
Data and Information • Data are raw facts that may or may not be useful for the user. • Information is processed data that holds some meaning to the user. • A physical database is just a file cabinet.
Data Sharing instead of physical duplication • Data sharing is defined as a process by which the data stored at a single location can be simultaneously accessed and modified by multiple users. • Data sharing aims at reducing the duplicity of data.
Class Activity • Which of the following has the most similar structure to that of a database? • A library of books • A store containing paper and pens • A car • A video cassette
Solution • A library resembles the structure of a database. This is because as books are arranged in each bookshelf of a library, similarly, data is stored and arranged in a database.
Class Activity- Data vs. Information • From the list below classify which of the following is data and which is information: • 12 • 12*8=96 • There are two people in the room. • Room
Solution • Data is: • 12 • Room • Information is: • 12*8= 96 • There are two people in the room
Class Activity- data sharing vs. non-sharing • In a track and field sports meet, multiple events are being conducted at different venues. The overall results need to be declared and compared, but the results for the track and field events have not been updated properly or in a timely manner. • The result is angry participants and confused spectators. What is this called in database terms?
Solution • Data inconsistency
DBMS Database Database Management Software
Database Advantages • Data Integrity • Data Accuracy • Control of Data dependence • Control of Data redundancy • Better Security
Database Data Model (Prototype) Introducing Data Models • Define the structure that needs to be conceptualized to implement a database. • Data models are: • A set of data structure types • A collection of operators • A set of integrity rules • You can view data model as a prototype of a database. It’s the framework for the way we want to implement our database.
Columns Rows Tables, also called RELATIONS • Tables are a collection of records that are arranged in the following format: • Rows (Records or Tuples) / Horizontal • Columns (Fields or Attributes) / Vertical
Components of a Database • The main components of a database are: • Record • Table
Relational Database Management System • An RDBMS has the following components: • Relation (table) • Tuple (record or row) • Attribute (column or field)
Other Types of Data Models • Record-based logical models • Network Model (Interconnected) • Hierarchical Model (Tree structure) • Object-based logical models
File or Record-based Model The data is structured in fixed format records. For example, a firm that has outsourced its processes to (partners in) multiple locations might NEED to use a record-based logical model. The partners might not have the same database system.
Car Entity Color Attributes Model Object-Based Logical Models For example, an automobile design firm that stores its information for designing car models might use an object-based logical model.
More About Object-oriented Data Model (OODM) The Object-oriented data model (OODM) covers: • Implementation for complex or large objects called BLOBs (Binary Large OBjects) like images. • High compatibility with Object-oriented programming languages, such as C++ and Java.
Class Activity • Identify the type of database that needs to be used for the scenario: • A company needs to store information including pictures on different types of automobiles, parts and their common characteristics, such as model, wheels, and weights.
Solution • An Object-oriented database is suited for the scenario.
Class Activity • Identify the type of database that needs to be used for the scenario. • A company needs to store text information on various departments of an organization.
Solution • A Relational database is suited for the scenario.
Class Activity • Identify the type of database that needs to be used for the scenario. • A garment manufacturing unit wants to store information of their product text feedback, such as shrinkage, color, and texture. In addition, the unit wants to integrate modeling video of various garments into the existing organizational database.
Solution • An Object-relational database is suited for the scenario.
Class Activity • Identify the components of OODM: • Car • Vehicle • Ignition • Motor-Bike • Two-wheeler • Shifting gears • Four-wheeler
Solution • The Objects are: • Car • Motor-Bike • The Methods are: • Ignition • Shifting-gears
Vehicle Two-wheeler Four-wheeler Solution (cont.) • Identifying Inheritance (letting other objects inherit characteristics)