Question

如果有人可以提供帮助，那么我对一个查询有困难

我要做的是按所选类别获取所有计数。例如，如果我没有选择任何类别，结果将是这样的：

Category-70 ( 2 ) <- Product-57, Product-56
Category-64 ( 2 ) <- Product-57, Product-50
Category-61 ( 1 ) <- Product-56
Category-73 ( 1 ) <- Product-50

这很容易。我有一个像这样的查询：

http://sqlfiddle.com/#!9/4f188/1

所以我想将类别ID传递给我的查询，并根据此ID获取计数，如果这样，如果我传递类别ID 70，结果必须是

Category-70 ( 2 ) <- Product-57, Product-56
Category-64 ( 1 ) <- Product-57, [Product-50 is gone because is not in cateogry id 70]
Category-61 ( 0 )
Category-73 ( 0 )

如果我传递类别ID 70和64，结果必须是

Category-70 ( 1 ) <- Product-57, [Product-56 is gone because is not in category 70 and 64]
Category-64 ( 1 ) <- Product-57
Category-61 ( 0 ) [Product-56 is gone, because is not in category 70 and 64 ]
Category-73 ( 0 ) [Product-50 is gone because is not in category 70 and 64]

或者如果我作为参数类别ID 73给出结果必须是

Category-70 ( 0 ) [products are not counted because they are not in 73]
Category-64 ( 1 ) <- Product-50
Category-61 ( 0 ) [products are not counted because they are not in 73]
Category-73 ( 1 ) <- Product-50

这是否可能:)，ty为任何帮助......

Answer 1

+1为SQL小提琴示例，非常有用。

我认为这可以解决您的问题（为您的加入添加子选择）

SELECT Concat('Category-',c.category_id), 
count(DISTINCT p2c.product_id) as products 
FROM category c 
LEFT JOIN product_to_category p2c 
  ON (c.category_id = p2c.category_id AND p2c.product_id) AND p2c.product_id in
  (select product_id from product_to_category where category_id = @input)
LEFT JOIN category_path cp ON (cp.category_id = c.category_id AND cp.path_id = c.category_id)    
WHERE
cp.level <= 2 
GROUP BY c.category_id
ORDER BY c.sort_order

Sql类产品计数查询

1 个答案: