Mysql 一个关系查询，不确定如何使用它来构建

这是目前我的表结构的一种更简单的形式。我有一个产品Id列表，我需要检查用户是否有产品Id，通过查看购物车属于用户的购物车产品，我知道，如上所述的关系。如果他有，我应该检索那个用户和他包含的信息。但我还需要检查产品的价格范围，即产品不得低于500，即cart_产品中的价格栏

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我如何构建这个sql？我正在考虑连接和EXISTS或IN的一些用法？

您想要这样的东西吗

carts
id user_id

cart_proucts
id cart_id product_id price

products
much details about the product...

或将IN与子查询一起使用：

SELECT DISTINCT Users.* FROM Users
INNER JOIN carts on carts.user_id = Users.id
INNER JOIN cart_products on carts.id = carts_products.cart_id
WHERE cart_products.price > X and cart_products.price < Y
AND cart_products.product_id IN (LIST OF PRODUCT IDS TO INCLUDE)
AND cart_products.product_id NOT IN (LIST OF PRODUCT IDS TO EXCLUDE)

我认为第一个选项可能会稍微优化一些，但完全有可能通过查询计划器对它们进行优化，使其保持一致。你必须运行一些基准来确定

==编辑2===

那么现在我想你是在要求一个十字路口

SELECT u.* from Users u WHERE u.id IN 
(
    SELECT Users.id FROM Users 
    INNER JOIN carts on carts.user_id = Users.id
    INNER JOIN cart_products on carts.id = carts_products.cart_id
    WHERE cart_products.price > X and cart_products.price < Y
    AND cart_products.product_id IN (LIST OF PRODUCT IDS)
)

我想这也可能和

SELECT DISTINCT Users.* FROM Users
INNER JOIN carts on carts.user_id = Users.id
INNER JOIN cart_products on carts.id = carts_products.cart_id
WHERE cart_products.price > X and cart_products.price < Y
AND cart_products.product_id IN (LIST OF PRODUCT IDS TO INCLUDE)

INTERSECT

SELECT DISTINCT Users.* FROM Users
INNER JOIN carts on carts.user_id = Users.id
INNER JOIN cart_products on carts.id = carts_products.cart_id
WHERE cart_products.price > X and cart_products.price < Y
AND cart_products.product_id NOT IN (LIST OF PRODUCT IDS TO EXCLUDE)

不确定哪些SQL实现允许除外连接，但另一种方法是使用左连接，如下所述：

==编辑3===

SELECT DISTINCT Users.* FROM Users
INNER JOIN carts on carts.user_id = Users.id
INNER JOIN cart_products on carts.id = carts_products.cart_id
WHERE cart_products.price > X and cart_products.price < Y
AND cart_products.product_id IN (LIST OF PRODUCT IDS TO INCLUDE)

EXCEPT

SELECT DISTINCT Users.* FROM Users
INNER JOIN carts on carts.user_id = Users.id
INNER JOIN cart_products on carts.id = carts_products.cart_id
WHERE cart_products.price > X and cart_products.price < Y
AND cart_products.product_id IN (LIST OF PRODUCT IDS TO EXCLUDE)

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使用LEFT JOIN+WHERE products.id不为空不需要加入产品-carts_产品在itI中有价格我不太明白他问题的最后一部分tho：产品不得低于500，即cart_产品中的价格列可以工作，但是我得到了我认为应该得到的多个结果，但是，是否有可能存储每个购物车，而不是因为购物车产品中有多个产品而返回10个相同购物车id的结果。因为我真正想要的是，如果用户在他的购物车中实际有它，就返回，而不是实际的购物车本身。第一个几乎是完美的，但是我也尝试不添加，但是用户还是返回了，假设用户有购物车产品。产品id有4和5，如果他两个都有，我不想返回给他选择不同的用户。*从用户内部加入carts on carts.id=users.id内部加入carts on carts.id=cart_products.cart_id WHERE users.total_sum>200和cart_products.product_id在4和cart_products.product_id不在5我不确定我是否理解你？也许你可以用额外的细节来编辑你的问题？听起来你想使用UNION、INTERSECT和EXCEPT，但我不确定你到底想要什么：看看我如何执行一个只从cart_产品中获取cart_id的查询，其中cart_id为5而不是product_id为4，如果我可以执行该查询，我可以简单地拆分上面的查询。。。因此，假设它有一行包含5，这很好，但如果它也有一行包含乘积_id 4，我们不要抓住它，这是一个包含2个子查询和联接的繁重查询。我建议通过将条件移动到内部联接来优化此查询，以便具有错误价格/id的产品不会包含在临时联接表中，临时联接表随后将通过WHERE条件：内部联接cart\u products ON cart\u products.cart\u id=carts.id和cart\u products.price>X和cart\u products.priceSELECT DISTINCT Users.* FROM Users INNER JOIN carts on carts.user_id = Users.id INNER JOIN cart_products on carts.id = carts_products.cart_id WHERE cart_products.price > X and cart_products.price < Y AND cart_products.product_id IN (LIST OF PRODUCT IDS TO INCLUDE) EXCEPT SELECT DISTINCT Users.* FROM Users INNER JOIN carts on carts.user_id = Users.id INNER JOIN cart_products on carts.id = carts_products.cart_id WHERE cart_products.price > X and cart_products.price < Y AND cart_products.product_id IN (LIST OF PRODUCT IDS TO EXCLUDE)

SELECT u.* from Users u WHERE u.id IN 
(
    SELECT Users.id FROM Users 
    INNER JOIN carts on carts.user_id = Users.id
    INNER JOIN cart_products on carts.id = carts_products.cart_id
    WHERE cart_products.price > X and cart_products.price < Y
    AND cart_products.product_id IN (LIST OF PRODUCT IDS TO INCLUDE)
)
AND u.id NOT IN
(
    SELECT Users.id FROM Users 
    INNER JOIN carts on carts.user_id = Users.id
    INNER JOIN cart_products on carts.id = carts_products.cart_id
    WHERE cart_products.price > X and cart_products.price < Y
    AND cart_products.product_id IN (LIST OF PRODUCT IDS TO EXCLUDE)
) 

SELECT *
FROM `users` `u`
JOIN `carts` `c` ON (`u`.`id` = `c`.`user_id`)
JOIN `cart_products` `cp` ON (`cp`.`cart_id` = `c`.`id`)
JOIN `products` `p` ON (`p`.`id` = `cp`.`product_id` AND `p`.`price` > `cp`.`price`)
WHERE `p`.`id` IN (...);