php | mysqli选择多表mysqli [保留]

Question

im trying to select multiple information from multi-tables but its a mess, please if someone can help me with some orientation how to query this i appreaciate <3

//Create the query and send it to the database.
$sql = "SELECT items.item_name, inventory.item_id, inventory.amount , player.id FROM items, inventory, player WHERE player.ID = '".$ID."'";
        if ($result = $mysqli->query($sql)) 
        {

            /* fetch associative array */
            $row = $result->fetch_assoc()
            echo  $row["item_name"];
            echo  $row["amount"];


            /* free result set */
            //$result->free();

        }

        $mysqli->close();

Answer 1

If I understand your question, try to use this:

SELECT items.item_name, inventory.item_id, inventory.ammount, player.id FROM items LEFT JOIN inventory ON items.id = inventory.items_id LEFT JOIN player ON “connect tables (player and items) with some id” WHERE player.ID = “.$ID.”

You need to JOIN three tables to get data FROM database ( see https://www.w3schools.com/sql/sql_join_inner.asp , https://www.w3schools.com/sql/sql_join_left.asp ).

To JOIN three tables you need to connect them by some ids or names.