<?php
$conn=mysqli_connect("localhost","root","123456789") or die("数据库服务器连接错误".mysqli_error());
mysqli_select_db($conn,"db_library") or die("数据库访问错误".mysqli_error( ));
mysqli_query($conn,"set names utf8");
?>
Warning: mysqli_error() expects exactly 1 parameter, 0 given in *********\conn\conn.php on line 3数据库访问错误
