3个不同的表有相同的外键，如何select

Question

假设我有 3 个不同的 tables，它们具有如下相同的外键：-

Table一个product_unit

| id  |  product_id  |  weight |  status_id  |
|:----|--------------|---------|------------:|
|  1  |      4       |   300   |      1      |
|  2  |      5       |   120   |      2      |

Table两个product_package

| id  |  product_id  |  weight |  status_id  |
|:----|--------------|---------|------------:|
|  1  |      4       |   1.2   |      1      |
|  2  |      5       |   480   |      1      |

Table三个product_carton

| id  |  product_id  |  weight |  status_id  |
|:----|--------------|---------|------------:|
|  1  |      4       |  10.2   |      1      |
|  2  |      5       |   4.8   |      2      |

其中tableproduct和statustable如下图：-

一个。产品table

    | id  |     name      |
    |:----|--------------:|
    |  4  |  Choco Cake   |
    |  5  | Hazelnut Bun  |

b。状态table

    | id  |  description  |
    |:----|--------------:|
    |  1  |   Available   |
    |  2  |  Unavailable  |

如何从这 3 个 table（product_unit、product_package 和 product_carton）中获取 所有状态 1 个查询 ?

到目前为止，我可以做到这一点：-

$product_info = Product::find()
->select([
      'product.name AS productName',
      'product_unit.weight AS weightUnit',
      'product_package.weight AS weightPackage',
      'product_carton.weight AS weightCarton', 
      'status.description AS statusDesc'])
->leftJoin('product_unit', 'product.id = product_unit.product_id')
->leftJoin('product_package', 'product.id = product_package.product_id')
->leftJoin('product_carton', 'product.id = product_carton.product_id')
->leftJoin('status', 'status.id = product_unit.status_id')
->asArray()
->all();

使用上面的查询我可以从product_unit[=96得到'statusDesc' =] ONLY，因为我 'leftJoin()' status table with product_unit table.

我怎样才能加入另一个2 tables (product_package & product_carton) 并从他们那里得到 statusDesc？有什么方法可以使用 1 Query?

Answer 1

$product_info = Product::find()
->select([
      'product.name AS productName',
      'product_unit.weight AS weightUnit',
      'product_package.weight AS weightPackage',
      'product_carton.weight AS weightCarton', 
      's1.description AS status_unit_Desc'])
      's2.description AS status_package_Desc'])
      's3.description AS status_carton_Desc'])
->leftJoin('product_unit', 'product.id = product_unit.product_id')
->leftJoin('product_package', 'product.id = product_package.product_id')
->leftJoin('product_carton', 'product.id = product_carton.product_id')
->leftJoin('status AS s1', 's1.id = product_unit.status_id')
->leftJoin('status AS s2', 's2.id = product_package.status_id')
->leftJoin('status AS s3', 's3.id = product_carton.status_id')
->asArray()
->all();

PS。也许inner Join会比left Join更合适？

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