在java中对数据库进行增删改查

1.java连接MySql数据库

 

 

代码区域:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
package com.oracle.jdbc.demo1;
 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
 
public class JDBCDemo {
     
    //四个属性(四个常量的字符串)
    /*
    jdbcName
    url
    user
    password
    */
    private static final String jdbcName="com.mysql.jdbc.Driver";
    private static final String url="jdbc:mysql://127.0.0.1:3306/emp_dept";
    private static final String user="root";
    private static final String password="123456";
    /*
     * 一个类(DriverManeger)四个接口(Connection、)
     * */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Connection conn=null;
        try {
            Class.forName(jdbcName);
            conn=DriverManager.getConnection(url, user, password);
            //获得conn就表示获取了数据库的连接
            System.out.println("连接数据库成功");
        catch (Exception e) {
            e.printStackTrace();
        finally {
            try {
                conn.close();
            catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
 
}

  

 

2.在java中向数据库添加数据

第一种方法:添加数据

 

代码区域:

 

 

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
package com.oracle.jdbc.demo2;
 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
 
public class JDBCAdd {
    private static final String jdbcName="com.mysql.jdbc.Driver";
    private static final String url="jdbc:mysql://127.0.0.1:3306/emp_dept";
    private static final String user="root";
    private static final String password="123456";
    /*
     * 一个类(DriverManeger)四个接口(Connection、PreparedStatement、)
     * */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Connection conn=null;
        try {
            Class.forName(jdbcName);
            conn=DriverManager.getConnection(url, user, password);
            //增加数据的操作
            String name="田雨";
            String sex="女";
            String sql="insert into person values(null,'"+name+"','"+sex+"')";
            PreparedStatement pst=conn.prepareStatement(sql); //准备执行sql语句
            int i=pst.executeUpdate(); //返回成功插入数据的行数
             
            System.out.println("成功添加了"+i+"条记录");
             
        catch (Exception e) {
            e.printStackTrace();
        finally {
            try {
                conn.close();
            catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
}

  

第二中方法:添加数据

 

代码区域:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
package com.oracle.jdbc.demo2;
 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
 
public class JDBCAdd2 {
     
    private static final String jdbcName="com.mysql.jdbc.Driver";
    private static final String url="jdbc:mysql://127.0.0.1:3306/emp_dept";
    private static final String user="root";
    private static final String password="123456";
    /*
     * 一个类(DriverManeger)四个接口(Connection、PreparedStatement、)
     * */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Connection conn=null;
        try {
            Class.forName(jdbcName);
            conn=DriverManager.getConnection(url, user, password);
            //增加数据的操作
            String name="田雨2";
            String sex="女";
            String sql="insert into person values(null,?,?)";
            PreparedStatement pst=conn.prepareStatement(sql); //准备执行sql语句
            pst.setString(1, name); //填充第1个问好
            pst.setString(2, sex); //填充第2个问好
            int i=pst.executeUpdate(); //返回成功插入数据的行数
             
            System.out.println("成功添加了"+i+"条记录");
             
        catch (Exception e) {
            e.printStackTrace();
        finally {
            try {
                conn.close();
            catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
 
}

  

3.在java中修改数据库的内容

 

代码区域:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
package com.oracle.jdbc.demo3;
 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
 
public class JDBCModify {  
    private static final String jdbcName="com.mysql.jdbc.Driver";
    private static final String url="jdbc:mysql://127.0.0.1:3306/emp_dept";
    private static final String user="root";
    private static final String password="123456";
    /*
     * 一个类(DriverManeger)四个接口(Connection、PreparedStatement、)
     * */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Connection conn=null;
        try {
            Class.forName(jdbcName);
            conn=DriverManager.getConnection(url, user, password);
            //修改数据的操作
            int id=2;
            String name="王希宝";
            String sex="男";
            String sql="update person set name=?,sex=? where id=?";
            PreparedStatement pst=conn.prepareStatement(sql); //准备执行sql语句
            pst.setString(1, name); //填充第1个问好
            pst.setString(2, sex); //填充第2个问好
            pst.setInt(3, id);
            int i=pst.executeUpdate(); //返回成功修改数据的行数       
            System.out.println("成功修改了"+i+"条记录");           
        catch (Exception e) {
            e.printStackTrace();
        finally {
            try {
                conn.close();
            catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
}

  

4.在java中删除数据库的内容

 

代码区域: 

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
package com.oracle.jdbc.demo4;
 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
 
public class JDBCDel {
     
    private static final String jdbcName="com.mysql.jdbc.Driver";
    private static final String url="jdbc:mysql://127.0.0.1:3306/emp_dept";
    private static final String user="root";
    private static final String password="123456";
    /*
     * 一个类(DriverManeger)四个接口(Connection、PreparedStatement、)
     * */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Connection conn=null;
        try {
            Class.forName(jdbcName);
            conn=DriverManager.getConnection(url, user, password);
            //删除数据的操作
            int id=2;
 
            String sql="delete from person where id=?";
            PreparedStatement pst=conn.prepareStatement(sql); //准备执行sql语句
            pst.setInt(1, id);
            int i=pst.executeUpdate(); //返回成功删除数据的行数
             
            System.out.println("成功删除了"+i+"条记录");
             
        catch (Exception e) {
            e.printStackTrace();
        finally {
            try {
                conn.close();
            catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
 
}

  

 

 

5.在java中查看数据库的内容

 

 代码区域:

 

 

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
package com.oracle.jdbc.demo5;
 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
 
public class JDBCFindAll {
     
    private static final String jdbcName="com.mysql.jdbc.Driver";
    private static final String url="jdbc:mysql://127.0.0.1:3306/emp_dept";
    private static final String user="root";
    private static final String password="123456";
    /*
     * 一个类(DriverManeger)四个接口(Connection、PreparedStatement、ResultSet、)
     * */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Connection conn=null;
        try {
            Class.forName(jdbcName);
            conn=DriverManager.getConnection(url, user, password);
            //查询数据的操作
            String sql="select id,name,sex from person";
            PreparedStatement pst=conn.prepareStatement(sql); //准备执行sql语句
            ResultSet rs=pst.executeQuery();
            while(rs.next()){
                int id=rs.getInt("id");
                String name=rs.getString("name");
                String sex=rs.getString("sex");
                System.out.println(id+" "+name+" "+sex);
            }
             
        catch (Exception e) {
            e.printStackTrace();
        finally {
            try {
                conn.close();
            catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
 
}

  

posted @ 2018-01-03 14:42  计算机语言  阅读(1287)  评论(0编辑  收藏  举报