php基础之连接mysql数据库和查询数据_MySQL

$con=mysql_connect($dbhostip,$username,$userpassword) or die("Unable to connect to the MySQL!");
$db = mysql_select_db($dbdatabasename,$con);
//执行语句
$qres=mysql_query("SELECT id,GoodsName FROM user");
//提取一条数据
11 $row=mysql_fetch_row($result);//mysql_fetch_row只能提取出查询结果的第一条记录
//提取多条记录
$reslist = array();
$i=0;
while($row = mysql_fetch_row($res)){
   $reslist[$i] = $row;
   $i++;
  }
mysql_close($con);

$db=new mysqli($dbhostip,$username,$userpassword,$dbdatabasename);

if(mysqli_connect_error()){  

　　echo 'Could not connect to database.';  

　　exit;

}

$result=$db->query("SELECT id,GoodsName FROM user");

$row=$result->fetch_row();

$dsn='mysql:host='.$dbhost.';dbname='.$dbdatabase.';' $dbh=new PDO($dsn,$username,$userpass);

$dsn='sqlite3:"D:\sqlite\user.db"';
$dbh=new PDO($dsn);

PostgreSQL：
$dsn='pgsql:host='.$dbhost.' port=5432 dbname='.$dbdatabase.' user='.$username.' password='.$userpass;
$dbh=new PDO($dsn);

$stmt=$dbh->query('SELECT id,name FROM user');
$row=$stmt->fetch();