PHP：从数据库查询中检索图像

Question

I have read many posts but i cannot find my answer. I am developing a food order/delivery website, which has many food cuisine categories, African, Alcohol, American... Each category is meant to have a different header image. So if the admin creates a new restaurant, when they select the restaurant cuisine, the correct header image will automatically display on the main websites products page for that said restaurant.

I have manually inputted the images into the database already, now i am trying to retrieve the database, my or die statement prints that it is not, but i have no error messages, which is confusing me.

    mysqli_report(MYSQLI_REPORT_INDEX);
    if (isset($_GET['rest_id'])) {

        $Rest = $_GET['rest_id'];

        $get_cat_img = "SELECT Cuisine_category
        FROM Rest_Category,Category_img
        INNER JOIN Rest_Details
        ON Rest_Category.Cat_ID = Rest_Details.Cat_ID
        WHERE Rest_Details.Cat_ID='$Rest'";

        $results = mysqli_query($dbc, $get_cat_img) or die("query is not working");
        $row=mysqli_fetch_array($results) or die ("q not working");
        $img=$row['Category_img'];
        echo $row['Category_img'];

        echo '<img src="'.$img.'" alt="background" style="width:100%;height:300px">';           
    }
    mysqli_close($dbc);

Answer 1

I think you may have just put a column name in the wrong place in your query.

If Category_img is a column name in the Rest_Category table, this is what you want to do

$get_cat_img = "SELECT Cuisine_category,Category_img
                FROM Rest_Category
                  INNER JOIN Rest_Details ON Rest_Category.Cat_ID = Rest_Details.Cat_ID
                WHERE Rest_Details.Cat_ID='$Rest'";

You can also shorten things a bit by using Alias's, it often makes the SQL code easier to read when it get past the very simple query.

$get_cat_img = "SELECT rc.Cuisine_category,rc.Category_img
                FROM Rest_Category rc
                  INNER JOIN Rest_Details rd ON rc.Cat_ID = rd.Cat_ID
                WHERE rd.Cat_ID='$Rest'";

Also modify your error reporting to actually report the real MYSQL error, it is much more usful that any message you can some up with

Like so

$results = mysqli_query($dbc, $get_cat_img);
if ( $result === false ) {
    echo 'query is not working: ' . mysqli_error($dbc);
    exit;
}