1. CSCI 6962: Server-side Design and Programming
Server-side Databases and Drivers 1

2. Outline Database servers and drivers Databases and the MVC paradigm
SQL overview
The Derby database server
Creating databases
Populating a database
MySQL

3. Databases and E-Commerce
Long term information stored in databases
Queries used to produce lists of products
Updates used to store orders
New record created for order in Order table
Customer information added to other tables
Quantities updated in inventory tables

4. Database Access Object
Database Servers
Access to database controlled by database server
Constantly running (like web container)
Server runs database queries and updates for databases it controls
Server handles security of database
Most are password-controlled
MySQL (free)
Oracle
MS Server
Not Access!
Database server
Web server
database
Database Access Object

5. Database Servers Programs create statement objects inside server
Server executes them on the database
Server stores results if query performed
Program may then access those results
Database server
Web server
Statement object select * from books
database
Database Access Object
ResultSet object productCode title price productCode title price productCode title price

6. Database Drivers Database server does not understand Java/C# commands
Only understands its own DBMS protocols
Each server has its own DBMS
Need a database driver to perform translation
Obtain from database server provider
Install in Java libraries
web container
database server
JDBC
database driver
JSF
page
Managed bean/ support class
DBMS

7. Databases and the MVC Paradigm
Usually do not directly access database from JSF/ASP pages
Requires both web programming and SQL knowledge
Usually done in model classes (such as managed bean)
Bean stores to database when commanded to
Bean performs database query when need to retrieve data
Often have built-in tools for database management
SqlDataSource object in ASP
web container
database server
JSF pages/
Managed bean
Support classes/ tools
ASP pages/
Code behind

8. SQL and Databases
Commands to database server use SQL (structured query language)
Common examples:
Query for all records matching some condition: select field from table where condition
Example: select * from books where price < 10
Delete all records matching some condition: delete from table where condition
Example: delete from books where ISBN = ‘0004’

9. SQL and Databases
Set new field value for all records matching some condition: update table set field = value WHERE condition
Example: update books set price = 9.95 where productCode = ‘0004’
Insert new record with given field values: insert into table (field, field, field…) values (value, value, value…)
Example: insert into books (productCode, title, price) values (‘0004’, ‘Green Eggs and Ham’, 9.95)

10. Derby Open source database server from Apache
Not as powerful as MySql, Oracle, etc.
Low memory overhead
Fewer access privileges required
Included in later versions of NetBeans
Create database, create connection to it
Create tables and execute SQL commands
Manipulate database from Java program running in NetBeans

11. Creating a Derby Database
Go to Services tab
Expand Databases node
Right-click Java DB node
Choose Create Database

12. Creating a Derby Database
Give database a name
Set User name to app
Strange schema errors otherwise
Set a password
(I usually also just use “app”)

13. Creating a Derby Database
Must connect to the database before using
Right-click on link corresponding to database
Choose Connect

14. Adding a Table Expand link to database Expand App node
Right-click Tables node
Select Create Table
Will get Create Table dialog

15. Adding a Table Add column for each field of table
First field should be key field
Check Primary key
Check Unique
Set types and other properties as needed
# of characters in VARCHAR
Etc.

16. Adding a Table
Final table structure now shown in services window

17. Manipulating the Database
Can execute queries directly (without using code)
Right click table
Select Execute Command
Brings up command window
Type in SQL statement
Right-click window
Select Run Statement

18. Viewing the Database Right click table Select View Data
Executes SELECT * FROM tablename query

19. MySQL Free database server Go to www.mysql.com Follow Products tab
Go to MySQL Community Server
Download and run

20. MySQL Database Driver From downloads page at mysql.com
Go to connectors page
Go to Connector/J (for Java)
Download and save
Extract the mysql-connector-java-5.version-bin.jar file

21. MySQL Database Driver
In Netbeans right-click Libraries folder of project
Choose Add JAR/Folder
Select mysql-connector-java-5. version-bin.jar file from downloads

22. The MySQL Interface
Command line interface to manipulate databases MySQL controls
Available from PROGRAMS menu
Will need to give password
Can create new databases create database databasename;

23. Creating Database Tables
Must define field names and field types
Some types:
varChar(n) : String of up to n characters
int(n) : integer up to n digits
double(n, d) : decimal number up to n digits and d after the decimal
Must declare a key field with “primary key”
create table tablename ( keyfieldname type primary key, fieldname type, fieldname type, … );