Laravel Eloquent 分层查询顺序

Question

需要一些帮助来获取集合，使用 Laravel Eloquent，来自 table 但由 parent_id 排序以实现，例如，以下层次结构：

非洲
- 东非
- 中非
- 北非
亚洲
- 中亚
- 东亚

(...) 等等

下面的table是我有的，只是parent_id订的。

我想要实现的是 parent > children 排序。在此先感谢您的帮助。

+----+---------------------------------+-----------+
| id | region_common_name              | parent_id |
+----+---------------------------------+-----------+
|  1 | Global                          |         0 |
|  2 | Africa                          |         1 |
| 14 | Americas                        |         1 |
| 33 | Antartica                       |         1 |
|  3 | Asia                            |         1 |
|  6 | Australasia                     |         1 |
|  4 | Europe                          |         1 |
| 10 | Eastern Africa                  |         2 |
| 11 | Middle Africa                   |         2 |
|  8 | Northern Africa                 |         2 |
| 12 | Southern Africa                 |         2 |
|  9 | Sub-Saharan Africa              |         2 |
| 13 | Western Africa                  |         2 |
| 20 | Central Asia                    |         3 |
| 21 | Eastern Asia                    |         3 |
| 22 | South-eastern Asia              |         3 |
| 23 | Southern Asia                   |         3 |
| 24 | Western Asia                    |         3 |
| 25 | Eastern Europe                  |         4 |
| 26 | Northern Europe                 |         4 |
| 27 | Southern Europe                 |         4 |
| 28 | Western Europe                  |         4 |
| 16 | Caribbean                       |         5 |
| 17 | Central America                 |         5 |
| 15 | Latin America and the Caribbean |         5 |
| 19 | Northern America                |         5 |
| 29 | Australia and New Zealand       |         6 |
| 30 | Melanesia                       |         6 |
| 31 | Micronesia                      |         6 |
| 32 | Polynesia                       |         6 |
|  5 | North America                   |        14 |
| 18 | South America                   |        14 |
|  7 | Southern America                |        18 |
+----+---------------------------------+-----------+

Answer 1

可以多条件下单，但必须自己加入。

SQL

中的示例

SELECT rp.region_common_name parent_name, r.region_common_name FROM regions r
INNER JOIN regions rp ON r.parent_id = rp.id
WHERE r.parent_id != 1 AND r.parent_id != 0
ORDER BY rp.region_common_name ACS, r.region_common_name ASC

因此您的结果将如下所示：

+---------------------------------+---------------------------------+
| parent_name                     | region_common_name              |
+---------------------------------+---------------------------------+
| Africa                          | Eastern Africa                  |
| Africa                          | Middle Africa                   |
| Americas                        | North America                   |
| Americas                        | South America                   |
+---------------------------------+---------------------------------+

在 eloquent 中，您可以使用 QueryBuilder 生成查询。它看起来像这样：

DB::table('regions as r')
    ->join('regions as rp', 'r.parent_id', '=', 'rp.id')
    ->where('r.parent_id', '!=', '0')
    ->where('r.parent_id', '!=', '1')
    ->orderBy('rp.region_common_name', 'asc')
    ->orderBy('r.region_common_name', 'asc')
    ->select('rp.region_common_name as parent_name', 'r.region_common_name as name');

Laravel Eloquent 分层查询顺序

Laravel Eloquent query order hierarchically

hierarchy

laravel

eloquent