Mysql 增删改

<?php
//删除
mysql_connect("localhost","root","123");

if(mysql_errno()>0){
    exit('数据库连接失败'.mysql_error());
}

mysql_set_charset("utf8");

mysql_select_db("stu");

$sql="delete from stu where id=10";

$res=mysql_query($sql);

if($res && mysql_affected_rows()){
    echo "删除成功， 删除了".mysql_affected_rows()."行";
    
}else{
    echo "删除失败";
}

mysql_close();

 

<?php
//查询
mysql_connect("localhost","root","123");

if(mysql_errno()>0){
    echo "连接数据库失败".mysql_error;
    
}

mysql_set_charset(utf8);

mysql_select_db("stu");

$sql="select id,name,sex,age from stu";

$res=mysql_query($sql);

if($res)(
    while ($row)
)

 

<?php
$link=mysql_connect('localhost','root','123');
if(!$link){
	die('连接失败：'.mysql_error());
}	
echo mysql_get_client_info();
echo "<br/>";
echo mysql_stat();
echo "<br/>";
echo mysql_client_encoding();
echo "<br/>";
echo mysql_get_host_info();
echo "<br/>";
echo mysql_get_proto_info();
echo "<br/>";

echo mysql_get_server_info();

 增

<?php
	header("content-type:text/html;charset=utf-8");
	//1.连接mysql服务器
	//mysql_connect		连接
	//mysql_pconnect	持久连接
	//$link = @mysql_connect("localhost","root","1234") || exit("数据库连接失败！");
	//$link = @mysql_connect("localhost","root","1234") || die("数据库连接失败！");
	$link = @mysql_connect("localhost","root","123");
	
	//2.判断是否连接成功
	//echo mysql_errno();
	//echo mysql_error();
	if(mysql_errno()){//判断错误号
		exit("错误号为：".mysql_errno()."错误信息为：".mysql_error().'，数据库连接失败！');//输出错误信息
	}
	
	//3.设置字符集
	mysql_set_charset("utf8");//设置客户端的字符集为utf8
	
	//4.选择数据库
	mysql_select_db("lamp69",$link);//use lamp69
	
	//5.准备sql语句
	//注册用户
	$sql = "insert into bbs_user(username,age,sex) values('zhangsan','20','0')";
	
	//6.发送sql语句
	$res = mysql_query($sql);//bool
	
	//7.处理结果
	if($res && mysql_insert_id()){
	
		echo "注册成功！用户id为:".mysql_insert_id();//获取上一步insert操作的主键id
	
	}else{
	
		echo "注册失败！";
	
	}
	
	//8.关闭数据库连接
	mysql_close();

 改

<?php
	//1.连接服务器
	mysql_connect("localhost","root","123");
	
	//2.判断错误
	if(mysql_errno()){
		exit("数据库连接失败！".mysql_error());
	}
	
	//3.设置字符集
	mysql_set_charset("utf8");
	
	//4.选择数据库
	mysql_select_db("lamp69");
	
	//5.准备sql语句
	//$sql = "update bbs_user set age=100 where id>=10 && id<=15";
	$sql = "update bbs_user set age=101 where id between 10 and 15";
	
	//6.发送sql语句
	$res = mysql_query($sql);
	
	//var_dump($res);
	
	//echo mysql_affected_rows();
	
	//7.处理结果
	if($res && mysql_affected_rows()){
		echo "修改成功！影响行数为：".mysql_affected_rows();//返回上一条sql语句执行后的影响行数
	}else{
		echo "没有修改！";
	}
	
	//8.关闭连接
	mysql_close();

 删

<?php
	//1.连接服务器
	mysql_connect("localhost","root","123");
	
	//2.判断错误
	if(mysql_errno()>0){
		exit("数据库连接失败！".mysql_error());
	}
	
	//3.设置字符集
	mysql_set_charset("utf8");
	
	//4.选择数据库
	mysql_select_db("lamp69");
	
	//5.准备sql语句
	$sql = "delete from bbs_user where id>10";
	
	//6.发送sql语句
	$res = mysql_query($sql);
	
	//7.处理结果
	if($res && mysql_affected_rows()){
		echo "删除成功，删除了".mysql_affected_rows()."行";
	}else{
		echo "删除失败！";
	}
	
	//8.关闭数据库连接
	mysql_close();

 查询

<?php
	//1.连接数据库
	mysql_connect("localhost","root","123");
	
	//2.判断错误
	if(mysql_errno()){//如果没有出错则返回 0（零）
		exit("数据库连接失败！".mysql_error());
	}
	
	//3.设置字符集
	mysql_set_charset("utf8");
	
	//4.选择数据库
	mysql_select_db("lamp69");
	
	//5.准备sql语句
	//$sql = "select id,username,age,sex from bbs_user where id>20";
	$sql = "select id,username,age,sex from bbs_user";
	
	//6.发送sql语句
	$res = mysql_query($sql);
	
	#var_dump($res);//返回结果集资源
	
	#echo mysql_num_rows($res);//获取结果集的行数
	
	//7.处理结果集
	if($res && mysql_num_rows($res)>0){
		
		//mysql_fetch_array 
		/*$row = mysql_fetch_array($res,MYSQL_ASSOC);
		
		echo "<pre>";
		var_dump($row);
		echo "</pre>";
		
		*/
		
		/*while($row = mysql_fetch_array($res,MYSQL_ASSOC)){
			echo "<pre>";
			var_dump($row);
			echo "</pre>";
		}*/
		
		//mysql_fetch_assoc
		while($row = mysql_fetch_assoc($res)){
			echo "<pre>";
			var_dump($row);
			echo "</pre>";
		}
		
		//mysql_fetch_object 
		/*while($row = mysql_fetch_object($res)){
			echo "<pre>";
			var_dump($row);
			echo "</pre>";
			//echo $row->username;
		}*/
		
		//mysql_fetch_row
		/*while($row = mysql_fetch_row($res)){
			echo "<pre>";
			var_dump($row);
			echo "</pre>";
		}*/
		
	}
	
	//8.关闭连接
	mysql_free_result($res);//释放结果集资源
	mysql_close();