Reputation: 53
I have a php variable that I want to fetch another field in database using this variable in my where clause.
My code:
require("conn.php");
$module = $_POST[ 'postmodule' ];
$query = "SELECT width FROM modules WHERE code = $module";
$result = mysqli_query($conn, $query);
$row = mysqli_fetch_assoc($result);
echo $row['width'];
But this is printing me nothing. Don't know where I am going wrong but any help would be appreciated.
Upvotes: 2
Views: 19521
Reputation: 21
write after Connection code below statement
$fieldname = $_POST[ 'fieldname' ];
Upvotes: 0
Reputation: 238
You can either break the string and concatenate the variable with ".."
require("conn.php");
$module = $_POST[ 'postmodule' ];
$query = "SELECT width FROM modules WHERE code = '".$module."'";
$result = mysqli_query($conn, $query);
$row = mysqli_fetch_assoc($result);
echo $row['width'];
Or you could wrap the variable in {}
within the string, as long as the string is wrapped in double quotes.
require("conn.php");
$module = $_POST[ 'postmodule' ];
$query = "SELECT width FROM modules WHERE code = '{$module}'";
$result = mysqli_query($conn, $query);
$row = mysqli_fetch_assoc($result);
echo $row['width'];
Also, if $module
is a string you will need to wrap the variable in single quotes as I did above.
Upvotes: 6