Question

PHP DELETE

$bid = $_GET['bid'];
$roll_id = $_GET['roll_id'];
$conn = mysqli_connect('localhost', 'root', 'root', 'isc', '3306');
if (!$conn) {
die('Could not connect to MySQL: ' . mysqli_connect_error());
}
mysqli_query($conn, 'SET NAMES \'UTF-8\'');

$result = mysqli_query("delete from bookingrecord where bid='$bid' && roll_id='$roll_id'");

if ($result){
echo "sucess";
}
else echo "eorror. ";

运行后就出现：

Warning: mysqli_query() expects at least 2 parameters, 1 given in C:\Program Files\Apache Software Foundation\Apache2.2\htdocs\ISC_PHP\CP3110_Library\CP3110_Manlibrary_do.php on line 15
eorror.

Answer 1

参数写错了。具体可以参考一下mysqli_query的调用方法。
mixed mysqli_query ( mysqli $link , string $query [, int $resultmode ] )

$result = mysqli_query("delete from bookingrecord where bid='$bid' && roll_id='$roll_id'");
这句参数出错了。

直接用 mysql_query不就很好用？

mysql_query($sql);

Answer 2

$bid = $_GET['bid'];
$roll_id = $_GET['roll_id'];
$conn = mysqli_connect('localhost', 'root', 'password');
if (!$conn) {
die('Could not connect to MySQL: ' . mysqli_connect_error());
}
else{
mysqli_query($conn, 'SET NAMES \'UTF-8\'');

$result = mysqli_query("delete from bookingrecord where bid='$bid' && roll_id='$roll_id'");
}

if ($result){
echo "sucess";
}
else echo "eorror. ";