简单的JDBC连接数据库的例子

今天复习一下基础，弄个jdbc连接数据库的小例子。
1.建表
[code]
create table USERS (
USER_NAME VARCHAR2(10) not null,
COME_FROM VARCHAR2(10),
constraint PK_USERS primary key (USER_NAME)
);
[/code]
2.插入数据
[code]
INSERT INTO USERS VALUES('张三','河北');
INSERT INTO USERS VALUES('李四','河南');
INSERT INTO USERS VALUES('王五','江苏');
INSERT INTO USERS VALUES('赵六','江西');
commit;
[/code]
3.建立JDBC连接工具类
[code]
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class JdbcUtil {
public static Connection getConnection() throws ClassNotFoundException, SQLException
{
Connection conn = null;
Class.forName("oracle.jdbc.driver.OracleDriver");
String url = "jdbc:oracle:thin:@localhost:1521:orcl";
conn = DriverManager.getConnection(url, "sundful", "oracle");
return conn;
}
}
[/code]
4.执行简单的查询
[code]
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class SimeSelectDemo {

/**
* @param args
* @throws Exception
*/
public static void main(String[] args) throws Exception {
Connection conn = null;
try{
conn = JdbcUtil.getConnection();
PreparedStatement ps = conn.prepareStatement("select * from users");
ResultSet rs = ps.executeQuery();
while (rs.next()) {
StringBuffer buffer = new StringBuffer();
buffer.append("用户名: ").append(rs.getString("user_name"));
buffer.append(" 籍贯: ").append(rs.getString("come_from"));
System.out.println(buffer);
}
}catch(SQLException e)
{
e.printStackTrace();
}catch(Exception e)
{
e.printStackTrace();
}finally{
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
[/code]
这样就能够实现基本的jdbc连接数据库并执行相关的操作了。