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查询3表上的多对多关系

[英]querying many-to-many relationship on 3 table

I have 3 table 我有3张桌子

  1. Partcar
  2. BarbellWheels
  3. Assembly

now, im confused how to manage this table to got connection, cause Partcar and Assembly is many-to-many relationship. 现在,我很困惑如何管理该表进行连接,导致PartcarAssembly是多对多的关系。 But, BarbellWheels will merging with Partcar in Assembly . 但是, BarbellWheels将在AssemblyPartcar合并。 How to make this 3 table have many-to-many relationship, Partcar and BarbellWheels with Assembly . 如何使这3个表具有多对多关系, PartcarBarbellWheelsAssembly And if it can, 3 table in 1, what a query to join them? 如果可以的话,请在1中的3个表中加入一个查询?

So far, what im thinking is, BarbellWheels join to Partcar 1st and then join to Assembly . 到目前为止,我的想法是, BarbellWheels加入Partcar 1st,然后加入Assembly

any advise? 有什么建议吗?

EDIT : 编辑:

There is 5 data on Partcar and must combine to 1 in Assembly and BarbellWheels will combine in Assembly with max 2 data on it. Partcar上有5个数据,必须在Assembly中合并为1,而BarbellWheels在Assembly中将合并有最多2个数据。

EDIT EDITED : im just relize i didnt mention the relationship. 编辑:即时通讯,我没有提到我的关系。 here's the code. 这是代码。

CREATE TABLE `Partcar` (
     `partcarID` Char(7) NOT NULL,
     `partcar_price` decimal(19,4) DEFAULT NULL,
     `partcar_name` varchar(100) DEFAULT NULL,
      PRIMARY KEY (`PartcarID`)
      );


ALTER TABLE `assembly` (
      `assemblyID` char(8) NOT NULL,
      `assembly_price` decimal(19,4) DEFAULT NULL,
      `partcarIDFK` int(10) NOT NULL,
      `barbellIDFK` int(10) NOT NULL,
      PRIMARY KEY (`assemblyID`),
      UNIQUE KEY `partcar` (`partcarIDFK`),
      UNIQUE KEY `barbell` (`barbellIDFK`),
      CONSTRAINT `partcarIDFK` FOREIGN KEY (`partcarIDFK`) REFERENCES partcar(`partcarID`),
      CONSTRAINT barbellIDFK FOREIGN KEY (`barbellIDFK`) REFERENCES barbell(`barbellID`)
      );

ALTER TABLE `barbell` (
      `barbellID` char(10) NOT NULL,
      `name_barbell` varchar(100) DEFAULT NULL,
      `carIDFK` int(10) NOT NULL,
      PRIMARY KEY (`barbellID`),
      UNIQUE KEY `car` (`carID`),

Consider the following: 考虑以下:

Recipes 菜谱

recipe_id recipe 
        1 cheese on toast
        2 macaroni and cheese

Ingredients 配料

ingredient_id ingredient
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          103 macaroni 

Recipe_Ingredient 配方成分

recipe_id ingredient_id
        1 101
        1 102
        2 103
        2 104

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