1. CS1222 Using Relational Databases and SQL
4/5/2019
CS Using Relational Databases and SQL
Introduction
Yuqing Zhu
Slides prepared by Randy Moss
Department of Computer Science
California State University, Los Angeles

2. 4/5/2019
Introduction

3. What is a database? A large, integrated collection of data Bank
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What is a database?
A large, integrated collection of data
Bank
Company
E-commerce
Government
University
……….
1. Introduction CS1222-Fall2017

4. Why use a database? Efficient data management access
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Why use a database?
Efficient data management access
Concurrent access and crash recovery
Data administration
Data integrity and security
Data independence
Reduced application development time
1. Introduction CS1222-Fall2017

5. Database models Physical model Logical model
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Database models
Physical model
How data is stored on a disk
Logical model
How data is organized
Examples
NoSQL
Key-value pair
Relational
A set of concepts to describe the structure of a database, and certain constraints that the database should obey.
1. Introduction CS1222-Fall2017

6. Relational model Most popular relational DBMS
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Relational model
Most popular relational DBMS
Oracle, Postgres, MySQL, SQL Server, Access, and more
How do Relational DBs store data?
Tables!
1. Introduction CS1222-Fall2017

7. Relational Database Concepts: Table
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Relational Database Concepts: Table
Field
(column,
Attribute)
Table
(Relation)
Table: Titles
Record (tuple, row)
1. Introduction CS1222-Fall2017

8. Relational Database Concepts
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Relational Database Concepts
Candidate Key
Uniquely identify a record
No two rows have the same candidate key
Maybe multiple candidate keys in a table
Primary key
Select a candidate key as the primary key
Only one primary key in a table
1. Introduction CS1222-Fall2017

9. Relational Database Concepts
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Relational Database Concepts
Candidate keys
titleID, Title, UPC
Primary key
Any ONE of the candidate keys
1. Introduction CS1222-Fall2017

10. Data type Determine what kind of data a field can store
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Data type
Determine what kind of data a field can store
Common data types
Text
Numeric
Byte integer, long integer, single, double, decimal
date/time, boolean
Special
1. Introduction CS1222-Fall2017

11. Schema “Definition” of a database Names of the tables
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Schema
“Definition” of a database
Names of the tables
Attributes and attribute types in each table
Constraints on each tables
Dependencies between tables
1. Introduction CS1222-Fall2017

12. Introduction to SQL Structured Query Language Open ANSI standard
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Introduction to SQL
Structured Query Language
Open ANSI standard
Supported by most databases
Some variation in implementation
A skill that is used by many people in many environments
Programmers
Database Administrators
Managers
1. Introduction CS1222-Fall2017

13. What Does SQL Do? Views information from relational database
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What Does SQL Do?
Views information from relational database
Single or Multiple Tables
Tools to Calculate and Summarize
Manipulates information in relational database
Insert Records
Update Records
Delete Records
Operates on entire recordset with single command
Defines relational database
Create Database, Tables, Primary and Foreign Keys
1. Introduction CS1222-Fall2017

14. SQL queries Basic format: If you select ALL attributes of a table
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SQL queries
Basic format:
SELECT filed_name1, field_name2,…
FROM table_name1, tabel_name2…
[WHERE conditions]
If you select ALL attributes of a table
SELECT *
FROM table_name
[WHERE conditions]
1. Introduction CS1222-Fall2017

15. SQL examples List all the attributes of all titles
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SQL examples
List all the attributes of all titles
SELECT *
FROM Titles
List the title and upc of all titles
SELECT title, upc
List the title and upc of the titles in the ‘metal’ genre
WHERE genre = ‘metal’
1. Introduction CS1222-Fall2017

16. 4/5/2019
Using MySQL

17. 2. Connect to the MySQL server
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2. Connect to the MySQL server
$mysql –p
You will be asked to input the password.
The password is the original password assigned to you, not the password you just changed to.
Change your password
mysql> set password=PASSWORD(“new password”);
$mysql –u username –p
1. Introduction CS1222-Fall2017

18. Run script files You’ll use four script files
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Run script files
You’ll use four script files
Lyric.sql: mostly for your labs
Books.sql: mostly for your homework
Orders.sql and Sailors.sql: mostly for exams
These four files are used to create tables in your database
1. Introduction CS1222-Fall2017

19. Some MySQL commands Help Reconnect to the server Display sever info
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Some MySQL commands
Help
? or \h or help;
Reconnect to the server
Connect;
Display sever info
Status
Quit MySQL
\q or quit; or exit;
1. Introduction CS1222-Fall2017

20. Some MySQL commands Show databases use database Show tables
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Some MySQL commands
Show databases
Show databases;
use database
Use dbname;
Show tables
Show tables;
Show table schema
Desc tablename
1. Introduction CS1222-Fall2017