错误:类mysqli的对象无法转换为字符串

I know that this question has been asked several times on this platform, however, none of them is able to solve my problem.

I am getting this error from the code below.

//This is working
$edition=mysqli_query($con,"select Price from books where Name='$book'");

//This is showing an error. The query is working when I run it on phpmyadmin.
//$edition=mysqli_query($con,"select Price from books where Name='$book' and Edition='$edition'");

//I am using mysqli_fetch_assoc to store it in $row and use the answer for later.
$row = mysqli_fetch_assoc($edition);

Let me know the problem and solution. Thanks in advance. :)

Here we go then :)

Considering in your working example the variable $book already been used, my bet would be on the only other variable $edition. I was thinking if you could debug the code and check the value assigned to it just before using it to make your query, you could confirm if it is a acceptable type.