我有两张表大致如下:
products product_attributes
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| id | name | | id | product_id | attribute | value |
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| 1 | product 1 | | 1 | 1 | size | big |
| 2 | product 2 | | 2 | 1 | colour | red |
| 3 | product 3 | | 3 | 2 | size | medium |
| 3 | product 3 | | 4 | 2 | age_range | 3-5 …