JAVA如何使用SQL语句??

举个例子
import java.sql.*;
public class JDBCSample {
public static void main(java.lang.String[] args) {
   try {
     // 这里加载驱动
     Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
   }
   catch (ClassNotFoundException e) {
     System.out.println("Unable to load Driver Class");
     return;
   }
   try {
     // 所有的驱动都必需使用try/catch块来接收异常
     // 必需指定数据库URL, 用户名, 密码
     Connection con = DriverManager.getConnection("jdbc:odbc:companydb","", "");
     // 创建一个可执行的SQL描述
     Statement stmt = con.createStatement();
     ResultSet rs = stmt.executeQuery("SELECT FIRST_NAME FROM EMPLOYEES");
     // 显示SQL结果
     while(rs.next()) {
       System.out.println(rs.getString("FIRST_NAME"));
     }
     // 释放数据库资源
     rs.close();
     stmt.close();
     con.close();
     }
     catch (SQLException se) {
       // 输出数据库连接错误信息
       System.out.println("SQL Exception: " + se.getMessage());
       se.printStackTrace(System.out);
      }
    }
}

同上但是要注意的是
Class.forName("");//括号里的字符窜是数据库驱动不同数据库驱动不同根据你的实际情况加载
DriverManager.getConnection("","","");//三个字符窜和你的数据库对应的不同数据库也不同

建议去google一下,效果比在论坛问好

package one;
import java.sql.*;
import com.microsoft.jdbc.sqlserver.SQLServerDriver;
public class lianjie {
    public lianjie() {
    }
    public Connection con()
        {
            try {
                Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
                Connection cong=DriverManager.getConnection("jdbc:microsoft:sqlserver://127.0.0.1:1433;databaseName=book","sa","sa");
                System.out.println("连接成功");
                return cong;
            } catch (Exception ex) {
                System.out.println("连接失败"+ex.toString());
                return null;
            }
        }
}
以上是连接数据库SQLServer2000的代码

import java.sql.*;public class com {
public Connection lianjie()//连接数据库的方法
    {
        try
        {
        Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
        Connection conn= DriverManager.getConnection("jdbc:sqlserver://127.0.0.1:1433;databaseName=book","sa","sa");
        System.out.println(" 连接成功");
        return conn;
        }catch(Exception ex)
        {
            System.out.print("连接的方法有问题"+ex.getMessage());
            return null;
        }
    }
public static void main(String[] args) {
com c=new com();
c.lianjie();
}
}
//以上是SQL2005连接数据库的方法,是成功的

你随便下一个jdbc的驱动，里面都有如何调用的例子的。

import java.sql.*;public class TestData {
Connection conn = null;
Statement st = null;
ResultSet rs = null;
//查询数据
public void SelectData() {
try {
conn = new Database().getConn();
st = conn.createStatement();
String sql = "select * from user";
rs = st.executeQuery(sql);
while (rs.next()) {
System.out.print(rs.getString("userid") + "-");
System.out.print(rs.getString("username") + "-");
System.out.print(rs.getString("password") + "-");
System.out.println(rs.getString("email"));
}
this.Close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
//插入数据
public void InsertData() {
try {
conn = new Database().getConn();
st = conn.createStatement();
String sql = "insert into user values('3','aaa','lyb','[email protected]')";
int rows = st.executeUpdate(sql);
this.Close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
//带参数插入数据
public void PreInsertData() {
try {
conn = new Database().getConn();
String sql = "insert into user(userid,username,password,email) values(?,?,?,?)";
//String sql="select * from user where username=?";
PreparedStatement ps = conn.prepareStatement(sql,ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);
ps.setString(1, "4");
ps.setString(2, "mmm");
ps.setString(3, "mmm");
ps.setString(4, "[email protected]");
rs=ps.executeQuery();
//this.Close();
/*while(rs.next()){
System.out.print(rs.getString("username"));
}*/
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
//修改数据
public void UpdateData() {
try {
conn = new Database().getConn();
st = conn.createStatement();
String sql = "update user set username='lyb11' where username='lyb'";
int rows = st.executeUpdate(sql);
// this.Close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
//删除数据
public void DelData() {
try {
conn = new Database().getConn();
st = conn.createStatement();
String sql = "delete from user where username='asd'";
int rows = st.executeUpdate(sql);
// this.Close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void Close() {
try {
rs.close();
st.close();
conn.close();
} catch (SQLException e) {
System.out.print("关闭数据库出错~~");
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

package com.zyh.connectiondb;import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;public class ConnectMysqlDB { public static void main(String[] args) {
String driverName ="com.mysql.jdbc.Driver";
String url ="jdbc:mysql://localhost:3306/person?user=root&password=root";
String sql ="select * from t_zyh_test";
try {
Class.forName(driverName);
Connection conn = DriverManager.getConnection(url);
Statement st = conn.createStatement();
ResultSet rs = st.executeQuery(sql);
while (rs.next()) {
String name =rs.getString(2);
System.out.println("name==>"+name);
}
} catch (Exception e){
e.printStackTrace();
}
}
}
网上大把的例子，兄弟多看书。谢谢

调试易

JAVA如何使用SQL语句??

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