K,所以我有两张桌子:
categories
+----+----------+
| id | slug |
+----+----------+
| 1 | billing |
| 2 | security |
| 3 | people |
| 4 | privacy |
| 5 | messages |
+----+----------+
categories_questions
+------------------+-------------+
| id | question_id | category_id |
+------------------+-------------+
| 1 | 1 | 2 |
| 2 | 2 | 5 |
| 3 | 3 | 2 |
| 4 | 4 | 4 |
| 5 | 4 | 2 | …