使用內部聯接查詢顯示2合1表

Question

大家好，我想顯示一個表，以便該表具有2個外鍵。我的食品和餐廳表具有名稱 column.i嘗試使用以下代碼，但我不知道如何顯示餐廳名稱和食品名稱。

$sql_select_food = "SELECT food.id,restaurant.name,food.name,food.restaurant_id,foodcategory.title from food INNER join foodcategory ON food.foodcategory_id=foodcategory.id INNER join restaurant ON food.restaurant_id=restaurant.id WHERE food.isActive = 1 ORDER BY food.updateDate DESC";
$result_select_food = mysqli_query($connection, $sql_select_food);
if (mysqli_num_rows($result_select_food) > 0) {
      while ($row_select_food = mysqli_fetch_assoc($result_select_food)) {
                        echo "
                            <tr>
                                <td>$row_select_food[name]</td>
                                <td>$row_select_food[name]</td>
                                <td>$row_select_food[title]</td>
                            </tr>
                ";
                    }
                }

Answer 1

使用列別名：

SELECT food.id AS food_id, restaurant.name AS restaurant_name, food.name AS food_name ...

然后

• $row_select_food['restaurant_name']是$row_select_food['restaurant_name']的名稱，
• $row_select_food['food_name']是食物的名稱，
• 等等

注意： AS關鍵字是可選的。

Answer 2

在列名上放置一個別名，然后在代碼中稍后以列名的形式調用它：

$sql_select_food = "SELECT food.id,restaurant.name as rname, food.name as fname, food.restaurant_id,foodcategory.title from food INNER join foodcategory ON food.foodcategory_id=foodcategory.id INNER join restaurant ON food.restaurant_id=restaurant.id WHERE food.isActive = 1 ORDER BY food.updateDate DESC";
$result_select_food = mysqli_query($connection, $sql_select_food);
if (mysqli_num_rows($result_select_food) > 0) {
      while ($row_select_food = mysqli_fetch_assoc($result_select_food)) {
                        echo "
                            <tr>
                                <td>$row_select_food[rname]</td>
                                <td>$row_select_food[fname]</td>
                                <td>$row_select_food[title]</td>
                            </tr>
                ";
                    }
                }