Java - Trang ď JDBC

Java Programming

How to Use Java DataBase
Connectivities (JDBC)
Incheon Paik

Java

1

Computer Industry Lab.


Contents
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Java

Simple SQL
Creating Table
Insert Data
Select Data
Accessing Data Using JDBC

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Computer Industry Lab.

Simple Database
Design

student
studentID
Name
Email
major

course

registration

call_number
name
teacher
semester

SID
call_num

Java

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Computer Industry Lab.

Database Table Creation
SQL Statement
CREATE TABLE student (
studentID INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(30) NOT NULL,
email VARCHAR(45),
major VARCHAR(15)
);
CREATE TABLE course (
call_number INT NOT NULL PRIMARY KEY,
name VARCHAR(25) NOT NULL,
teacher VARCHAR(30),
semester VARCHAR(10) NOT NULL
);
CREATE TABLE registration (
SID INT NOT NULL,
call_num INT NOT NULL,
PRIMARY KEY (SID, call_num)
);

Java

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Database Table Creation (Running Screen)

Java

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Table Structure

Java

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Insert & Select Data

Java

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Select Data

Java

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Use JDBC
import java.sql.*;
import java.io.*;
// This example is running with MySql.
public class MyTest{
public static void main(String[] args){
String url =
"jdbc:mysql://localhost/paikic?useUnicode=true&characterEncoding=EUC_JP";
String query = "select * from course";
Connection myCon = null;
Statement stmt = null;
try{
Class.forName("org.gjt.mm.mysql.Driver");
}catch(ClassNotFoundException e){
System.err.println("Class Load Error");
System.err.println(e.getMessage());
}
try{
System.out.println("Trying to connect...");
myCon = DriverManager.getConnection(url,"root", "sccp2002");
stmt = myCon.createStatement();
ResultSet rs = stmt.executeQuery(query);
while(rs.next()){
String col1 = rs.getString(1);
String col2 = rs.getString(2);
String col3 = rs.getString(3);
String col4 = rs.getString(4);

System.out.println(" " + col1 + " : " + col2 + " : " + col3 + " : " +

col4);

}

Java

}

}
rs.close(); stmt.close(); myCon.close();
} catch(SQLException e){
System.out.println("MY" + url+" : ");
System.err.println(e.getMessage()+e.toString());
}
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Use JDBC (Running
Screen)

Java

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Computer Industry Lab.