Rhythmk 一步一步学 JAVA（2） ： 操作 MYSQL 数据库

1. 下载 如：mysql-connector-java-5.1.22.zip 解压获取 jar 连接包。

2. 引入项目： 右键项目名--->Build Path—>Configure Build Path... 选择 Libraries 然后再选择 右边

第二个选项Add External Jars 导入 mysql -.jar

3. 新建数据表：

CREATE TABLE `user` (
`ID` int(11) NOT NULL AUTO_INCREMENT,
`Name` varchar(32) NOT NULL,
`Age` int(11) NOT NULL,
`AddTime` datetime NOT NULL,
PRIMARY KEY (`ID`)
) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=utf8;

4. 测试程序：

package App1.Rhythmk.com;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;

import com.mysql.jdbc.Statement;

/*
*
*  建表脚本
CREATE TABLE `user` (
`ID` int(11) NOT NULL AUTO_INCREMENT,
`Name` varchar(32) NOT NULL,
`Age` int(11) NOT NULL,
`AddTime` datetime NOT NULL,
PRIMARY KEY (`ID`)
) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=utf8;
*/

public class ThirdMysql {

// final 类似 .NET 中 const
private static final String DatabaseConURL = "jdbc:mysql://127.0.0.1:3306/rhythmkdb";

/**
*  rhythmK
* 1.右键项目名--->Build Path—>Configure Build Path... 会弹出来一个框 在那四个选项选择
* Libraries 然后再选择 右边 第二个选项Add External Jars
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
Test();
ExcuteByParam();
Add();
Update();
Select();
Del();
}

public static void Test() {
try {
Connection con = null;
Class.forName("com.mysql.jdbc.Driver").newInstance();
con = DriverManager
.getConnection(DatabaseConURL, "root", "wangkun");
Msg("Mysql 连接成功。");

} catch (Exception ex) {
Msg(ex.toString());
}
}

public static void Add() {
String sql = "Insert  into  `user` (Name ,Age, Addtime ) ";
sql += " values ('rhythmk',21,'2012-1-1')  ";
try {
Connection con = null;
Class.forName("com.mysql.jdbc.Driver").newInstance();
con = DriverManager
.getConnection(DatabaseConURL, "root", "wangkun");

java.sql.Statement statement = con.createStatement();
statement.executeUpdate(sql);
ResultSet result = statement
.executeQuery("select  LAST_INSERT_ID() ");
int resultID = 0;
if (result.next()) {
// 此出索引不是从0开始 ..
resultID = result.getInt(1);
}
Msg("Add 数据库得到返回ID" + resultID);

} catch (Exception ex) {
Msg(ex.toString());
}
}

public static void Update() {
String sql = " Update `user` set Name= 'rhythmk.com' where ID<3 ";
try {
Connection con = null;
Class.forName("com.mysql.jdbc.Driver").newInstance();
con = DriverManager
.getConnection(DatabaseConURL, "root", "wangkun");

java.sql.Statement statement = con.createStatement();
int resultID = statement.executeUpdate(sql);

Msg("Update 数据库得到返回ID" + resultID);

} catch (Exception ex) {
Msg(ex.toString());
}
}

public static void Del() {
String sql = " Delete from `user`  where ID=3 ";
try {
Connection con = null;
Class.forName("com.mysql.jdbc.Driver").newInstance();
con = DriverManager
.getConnection(DatabaseConURL, "root", "wangkun");

java.sql.Statement statement = con.createStatement();
int resultID = statement.executeUpdate(sql);

Msg("Del 数据库得到返回ID" + resultID);

} catch (Exception ex) {
Msg(ex.toString());
}
}

public static void Select() {
String sql = " Select ID,Name from `user`   ";
try {
Connection con = null;
Class.forName("com.mysql.jdbc.Driver").newInstance();
con = DriverManager
.getConnection(DatabaseConURL, "root", "wangkun");

java.sql.Statement statement = con.createStatement();
ResultSet result = statement.executeQuery(sql);

String resultStr = "";
while (result.next()) {
resultStr += "\r\n ID=" + result.getString(1);
resultStr += ", Name=" + result.getString("Name");
}

Msg(resultStr);
// statement.executeUpdate(sql);

} catch (Exception ex) {
Msg(ex.toString());
}
}

public static void ExcuteByParam() {
String sql = "select * from  `user` where Name =?";
try {
Connection con = null;
Class.forName("com.mysql.jdbc.Driver").newInstance();
con = DriverManager
.getConnection(DatabaseConURL, "root", "wangkun");

java.sql.PreparedStatement preparedsm = con.prepareStatement(sql);
preparedsm.setString(1, "rhythmk");
ResultSet result = preparedsm.executeQuery();

String resultStr = "";
while (result.next()) {
resultStr += "\r\n ID=" + result.getString(1);
resultStr += ", Name=" + result.getString("Name");
}

Msg("ExcuteByParam:\r\n" + resultStr);
// statement.executeUpdate(sql);

} catch (Exception ex) {
Msg(ex.toString());
}
}

public static void Msg(String msg) {
System.out.println(msg);
}

}