用PHP更新MYSQl会导致空白页面

Question

i am trying to update mysql table with php grabbing data from a form.

When i run the script with this

$query="UPDATE customers SET background='$_GET['background']',font='$_GET['font']',fontcolour='$_GET['fontcolour']',fontsize='$_GET['fontsize']',title='$_GET['title']' WHERE client='$_GET['client']'";

i get a black screen but if i do the below script

$background=$_GET['background'];
$client=$_GET['client'];
$query="UPDATE customers SET background='$background' WHERE client='$client'";

it goes through fine

although i can do it this way i am trying to understand why i can not just put the get right into the query rather than having more lines of code than necessary.

NOTE: all other code stripped can post if required.

Answer 1

Change your code to this

$query="UPDATE customers SET background='" . $_GET['background'] . "',font='" . $_GET['font'] . "',fontcolour='" . $_GET['fontcolour'] . "',fontsize='" . $_GET['fontsize'] . "',title='" . $_GET['title'] . "' WHERE client='" . $_GET['client']."'";

Also, your code is vulnerable to SQL injection