jdbc数据库基础

1.在数据库中新建数据表

CREATE TABLE t_user(
ID NUMBER,
NAME VARCHAR2(32),
age VARCHAR2(5),
birth DATE
);
SELECT * FROM t_user;
CREATE SEQUENCE seq_user;
INSERT INTO t_user VALUES(
seq_user.nextval,'zhangsan','23',SYSDATE);
COMMIT;

2.新建java工程

3.导入jdbc所需要的jar包 jar包路径“D:\oracle\product\11.2.0\dbhome_1\jdbc\lib”文件夹下

右键工程-新建folder,用lib命名，然后将jar包导入，再build path

4.以对数据库做一个查询操作为例，进行jdbc的测试

public static void query()throws ClassNotFoundException, SQLException {

//1.加载驱动

Class.forName("oracle.jdbc.driver.OracleDriver");

//2.定义连接URL

String url="jdbc:oracle:thin:@localhost:1521:orcl";

//3.获取数据库的连接

Connection conn = DriverManager.getConnection(url,"scott","tiger");

//4.创建statement对象

Statement st = conn.createStatement();//用来执行sql语句，返回结果集

//5.执行查询或更新

String sql = "select id,name,age,birth from t_user";

ResultSet rs =sql.executeQuery(sql);

//6.遍历结果集对象

while（rs.next()）{

int id =rs.getInt("id");

String name=rs.getString("name");//这里的变量名可以随便起，但是列名一定不要写错<span style="color:#FF0000;">import java.sql.Connection;
import java.sql.Date;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class UserDao {

public static void query() throws ClassNotFoundException, SQLException{
Class.forName("oracle.jdbc.driver.OracleDriver");
String url="jdbc:oracle:thin:@localhost:1521:orcl";
Connection conn=DriverManager.getConnection(url,"scott","tiger");
String sql="select id,name,age,birth from t_user";
Statement st =conn.createStatement();
ResultSet rs =st.executeQuery(sql);
while(rs.next()){
int id = rs.getInt("id");
String name = rs.getString("name");
String age=rs.getString("age");
Date birth=rs.getDate("birth");
System.out.println(id+"$"+name+"$"+age+"$"+birth);
conn.close();
st.close();
rs.close();

}
}
public static void main(String[] args) throws ClassNotFoundException, SQLException {
query();

}

}</span>

String age = rs.getString("age");

Date birth =rs.getDate("birth");

system.out.println(id+":"+name+":"+age+":"+birth);

//7.关闭连接释放资源

rs.close();

st.close();

conn.close();

}

}

public static void main (String[] args) ClassNotFoundException, SQLException{

query();

}

需要注意的是：

1.千万不要忘记导入jar包

2.建立连接的时候会抛出异常