MySQL返回MIN ID而不是MAX ID？

Question

I have a table with an AI column called 'id'. This column is UNSIGNED and has 6 entries. So id: 6 is the MAX value in the column. Using PHP to call forth the max id in the table, it always prints out the least value. This is what i'm doing:

$MAX_ID = $db->query("SELECT MAX(id) FROM table");
                    echo "Hello" + $MAX_ID;

I've tried all the ways of doing this, like ORDER BY and id=("SELECT FROM MAX(id)"), but 1 is still being returned. I am using PHPMyAdmin, and when I do the SQL query there, the right value is being returned. What am I doing wrong?

Answer 1

No, what you're getting is just a MySQLi result object ( $MAX_ID ).

Execute the query → Fetch the rows.

$query = $db->query("SELECT MAX(id) FROM Entertainment"); // execute
$max_id = $query->fetch_array(); // fetch
echo $max_id[0];

Additional Note: Use . for concatenation, not + :

echo 'max: ' . $max_id[0];

Answer 2

Take a look at the mysqli documentation . The value being returned is a result object, not the direct result data from the query: You'll need to use mysqli's accessor methods to extract actual result rows.