Introduction to Information and Computer Science Databases and SQL Lecture c This material (Comp4_Unit6c) was developed by Oregon Health and Science University,

Introduction to Information and Computer Science

Databases and SQL

Lecture c

This material (Comp4_Unit6c) was developed by Oregon Health and Science University, funded by the Department of Health and Human Services, Office of the National Coordinator for Health Information Technology under Award Number

IU24OC000015.

Databases and SQLLearning Objectives

• Define and describe the purpose of databases (Lecture a)• Define a relational database (Lecture a)• Describe data modeling and normalization (Lecture b)• Describe the structured query language (SQL) (Lecture c)• Define the basic data operations for relational databases and how to

implement them in SQL (Lecture c)• Design a simple relational database and create corresponding SQL

commands (Lecture c)• Examine the structure of a healthcare database component (Lecture

d)

2Health IT Workforce Curriculum Version 3.0/Spring 2012

Introduction to Information and Computer Science Databases and SQL

Lecture c

SQL

• Used to manage and access database information

• ANSI, ISO and IEC standard– DBMS have custom extensions!

• Extensive language– We’ll look at a few basic commands



Lecture c

Example

• Make a space for the tables by creating the database– create database <name>

sql> create database contacts• To remove:

– drop database <name>



Lecture c

Create the Tables

• create table <name> (<column information>);• Column information consists of column names

and data types• Tables also have extra information• To remove:

– drop table <name>



Lecture c

SQL Basic Data Types

Data Type Description

integer or int Whole numbers

float Floating point number

date Date

time Time

char (length) Fixed number of characters

varchar (length) Variable number of characters

6.14 Table: SQL Basic Data Types (PD-US, 2011).



Lecture c

Create Company Table

sql> create table company (id integer auto_increment,

-> name varchar(50),

-> address varchar(50),

-> city varchar(50),

-> state char(2),

-> primary key(id));



Lecture c

Create person table

sql> create table person(id integer auto_increment,

-> first_name varchar(50),

-> last_name varchar(50),

-> company_id integer,

-> primary key(id),

-> foreign key(company_id) references company(id));



Lecture c

View Tables

6.15 Figure: SQL command and output (PD-US, 2011).



Lecture c

View Table Columns

6.16 Figure: View table columns (PD-US, 2011).



Lecture c

Same Basic Operations

• Add an entry• Retrieve an entry• Delete an entry• Modify an entry



Lecture c

Add an Entry

• Insert into <table> (columns) values (values);

• First add company entries:sql> insert into company (name, address, city, state)

-> values ('Community Hospital, Inc.', '1312 Main', 'Portland', 'OR');

sql> insert into company (name, address, city, state)

-> values ('Oakland Providers LLC', '14 12th St.', 'Oakland', 'CA');



Lecture c

Add Persons

• Now add people and their associated companies:sql> insert into person (first_name, last_name, company_id)

-> values ('Bill', 'Robeson', 1);

sql> insert into person (first_name, last_name, company_id)

-> values ('Walter', 'Schmidt', 2);


-> values ('Mary', 'Stahl', 2);


-> values ('Albert', 'Brookings', 1);


-> values ('Catherine', 'David', 2);



Lecture c

Retrieve an Entry

6.17 Figure: Retrieve an entry (PD-US).



Lecture c

Add Sorting

6.18 Figure: Add sorting (PD-US, 2011).



Lecture c

Add Selectivity

6.19 Figure: Add selectivity (PD-US, 2011).



Lecture c

Retrieve from Multiple Tables

6.20 Figure: Retrieve from multiple tables (PD-US, 2011).



Lecture c

Create a Complex SQL Statement

6.21 Figure: Create a Complex SQL Statement (PD-US, 2011).



Lecture c

Delete an Entry

• delete from <table> where <constraints>;

• Remove Mary from contact list:sql> delete from person where first_name='Mary' and last_name='Stahl';

1 row affected



Lecture c

Modify an Entry

• update <table> set <column>=<data> where <constraints>;



Lecture c

New Company Name

6.22 Figure: Modify company name (PD-US, 2011).



Lecture c

New Company Name

6.23 Figure: New company name (PD-US, 2011).



Lecture c

Verify Again

6.24 Figure: Verify again (PD-US, 2011).



Lecture c

Databases and SQLSummary – Lecture c

• SQL is a language for creating, accessing and updating databases– Create tables– Insert data– Update data– Retrieve (select) data– Delete data



Lecture c

Databases and SQLReferences – Lecture c

References• Chen, P. P.-S. (1976). The Entity-Relationship Model - Toward a Unified View of Data. ACM Transactions on

Database Systems, 1(1).• International Organization for Standardization. (2008). Information technology -- Database languages -- SQL (No.

ISO/IEC 9075-(1-4,9-11,13,14)).• Kent, W. (1983). A simple guide to five normal forms in relational database theory. Communications of the ACM,

26(2).

Charts, Tables, Figures:• 6.14 Table: SQL Basic Data Types (PD-US, 2011).• 6.15 Figure: View tables (PD-US, 2011). • 6.16 Figure: View table columns (PD-US, 2011). • 6.17 Figure: Retrieve an entry (PD-US, 2011). • 6.18 Figure: Add sorting (PD-US, 2011). • 6.19 Figure: Add selectivity (PD-US, 2011). • 6.20 Figure: Retrieve from multiple tables (PD-US, 2011).• 6.21 Figure: Create a Complex SQL Statement (PD-US, 2011).• 6.22 Figure: Modify company name (PD-US, 2011). • 6.23 Figure: New company name (PD-US, 2011). • 6.24 Figure: Verify again (PD-US, 2011).



Lecture c

Documents

Introduction to Information and Computer Science Databases and SQL Lecture c This material (Comp4_Unit6c) was developed by Oregon Health and Science University,