php数据库访问

/*//方式一：已通过时
//1.造一个链接（创建通道）
$db = mysql_connect("localhost","root","123");
//2.选择要操做哪个数据库
mysql_select_db("mydb",$db);
//3.写SQL语句
$sql = "select * from Info";
//4.执行SQL语句，返回结果集
$result = mysql_query($sql);
//5.从结果集中取数据
while($row = mysql_fetch_row($result))
{
var_dump($row);
}*/

//方式二：面向对象的方式
//1.造一个链接对象
//$db = new MySQLi("localhost","root","123","mydb");
//2.判断链接是否出错
/*if(mysqli_connect_error())
{
echo "链接失败";
exit(); //退出程序
}*/

//!mysqli_connect_error() or die("链接失败！");

//3.写SQL语句
//$sql = "select count(*) from Info";
//$sql = "insert into Info values('p001','','','','')";

//4.执行SQL语句,查询语句若是执行成功返回结果集对象，若是执行失败返回false
//$result = $db->query($sql);

 

//5.从结果集中读取数据
//if($result)
//{
//var_dump($result->fetch_row()); //返回一行数据的数组（索引数组）
/*while($row = $result->fetch_row())
{
var_dump($row);
}*/

//var_dump($result->fetch_assoc());//返回一行数据（关联数组）

//$shuju = $result->fetch_all();//返回全部数据（二维数组）

//var_dump($result->fetch_object());//返回一行数据（对象）

//echo $shuju[0][0];


//}

//1.造链接对象
$db = new MySQLi("localhost","root","cuisheng520","cui");
//2.判断是否出错
!mysqli_connect_error() or die("链接失败！");
//3.写SQL语句
$sql = "select * from nation";
//4.执行SQL语句
$result = $db->query($sql);
//5.取数据
if($result)
{
$attr = $result->fetch_all();

echo "<select>";

foreach($attr as $v)
{
echo "<option value='{$v[0]}'>{$v[1]}</option>";
}

echo "</select>";
}