Sequelize hasMany 通过另一个表

Posted 2023-03-07

【中文标题】Sequelize hasMany 通过另一个表

【英文标题】：Sequelize hasMany through another table

【发布时间】：2015-05-23 19:26:32

【问题描述】：

好的，所以我有以下三个models

模块：

    var Module = sequelize.define('module', 
        id: DataTypes.INTEGER,
        name: DataTypes.STRING,
        description: DataTypes.STRING,
        category_id: DataTypes.STRING,
        module_type_id: DataTypes.STRING,
        gives_score: DataTypes.INTEGER,
        duration: DataTypes.STRING,
        price: DataTypes.STRING

    , 
        freezeTableName: true
)

能力：

Competence = sequelize.define('competence', 
        id: DataTypes.INTEGER,
        name: DataTypes.STRING,
        organization_id: DataTypes.INTEGER,
        competence_type_id: DataTypes.INTEGER
    ,freezeTableName:true)

Module_has_competence：

        Module_has_competence = sequelize.define('module_has_competence', 
    id: DataTypes.INTEGER,
    module_id: DataTypes.INTEGER,
    competence_id: DataTypes.INTEGER,
    score: DataTypes.STRING
,
    freezeTableName: true
)

如您所见，表之间的关系是n:m

所以现在我想找到Module 拥有的所有Competence：

所以我创建了以下关系：

Module.hasMany(Competence, through: Module_has_competence, foreignKey: 'module_id');

但是当我尝试运行时：

  retrieveById: function (quote_id, onSuccess, onError) 
                Module.find(include: [ all: true ],where: id: quote_id)
                    .success(onSuccess).error(onError);
            

它什么也不返回。但如果我删除关系，它只返回Module

谁能告诉我我做错了什么？

当我调试时

当我调试它时，它没有记录任何 sql，可悲的是它似乎只是忽略了 sql 调用？

【问题讨论】：

你能发布这些语句产生的 SQL 查询吗？那时您的数据库状态也会有所帮助

@DanRocha 请坚持住：D

@DanRocha 遗憾的是它没有发布任何 sql：s 我所有其他功能都可以，但这个没有：s

您确定您正在访问该代码吗？也可以尝试使用 findAll 来测试 find 是否有问题

@dege 代码是可访问的，因为一旦我删除它收集模块的行

【参考方案1】：

据我了解，您创建了多对多关系的表，并且当您查询“模块”时，您希望所有“能力”都与之关联。

虽然我无法让.hasMany() 工作，但产生的错误是：

Trace: [TypeError: Cannot call method 'replace' of undefined]
    at null.<anonymous> (/Users/sjlu/Development/29165644/app.js:61:13)
    at tryCatch1 (/Users/sjlu/Development/29165644/node_modules/sequelize/node_modules/bluebird/js/main/util.js:45:21)
    at Promise._callHandler (/Users/sjlu/Development/29165644/node_modules/sequelize/node_modules/bluebird/js/main/promise.js:571:13)
    at Promise._settlePromiseFromHandler (/Users/sjlu/Development/29165644/node_modules/sequelize/node_modules/bluebird/js/main/promise.js:581:18)
    at Promise._settlePromiseAt (/Users/sjlu/Development/29165644/node_modules/sequelize/node_modules/bluebird/js/main/promise.js:713:18)
    at Promise._settlePromiseAt (/Users/sjlu/Development/29165644/node_modules/sequelize/lib/promise.js:76:18)
    at Promise._settlePromises (/Users/sjlu/Development/29165644/node_modules/sequelize/node_modules/bluebird/js/main/promise.js:854:14)
    at Async._consumeFunctionBuffer (/Users/sjlu/Development/29165644/node_modules/sequelize/node_modules/bluebird/js/main/async.js:85:12)
    at Async.consumeFunctionBuffer (/Users/sjlu/Development/29165644/node_modules/sequelize/node_modules/bluebird/js/main/async.js:40:14)
    at process._tickCallback (node.js:442:13)

几乎无法调试此输出。

但是，我能够创建您的模型绑定并使用 .belongsToMany() 关联正确查询它

Competence.belongsToMany(Module, 
    through: Module_has_competence,
    as: 'module',
    foreignKey: 'module_id'
)
Module.belongsToMany(Competence, 
    through: Module_has_competence,
    as: 'competence',
    foreignKey: 'competence_id'
)

输出您正在寻找的查询

  SELECT `module`.`id`, 
         `module`.`name`, 
         `module`.`description`, 
         `module`.`category_id`, 
         `module`.`module_type_id`, 
         `module`.`gives_score`, 
         `module`.`duration`, 
         `module`.`price`, 
         `module`.`createdat`, 
         `module`.`updatedat`, 
         `competence`.`id`                                  AS `competence.id`, 
         `competence`.`name`                                AS `competence.name`, 
         `competence`.`organization_id`                     AS 
         `competence.organization_id`, 
         `competence`.`competence_type_id`                  AS 
         `competence.competence_type_id`, 
         `competence`.`createdat`                           AS 
         `competence.createdAt`, 
         `competence`.`updatedat`                           AS 
         `competence.updatedAt`, 
         `competence.module_has_competence`.`id`            AS 
         `competence.module_has_competence.id`, 
         `competence.module_has_competence`.`module_id`     AS 
         `competence.module_has_competence.module_id`, 
         `competence.module_has_competence`.`competence_id` AS 
         `competence.module_has_competence.competence_id`, 
         `competence.module_has_competence`.`score`         AS 
         `competence.module_has_competence.score`, 
         `competence.module_has_competence`.`createdat`     AS 
         `competence.module_has_competence.createdAt`, 
         `competence.module_has_competence`.`updatedat`     AS 
         `competence.module_has_competence.updatedAt` 
  FROM   `module` AS `module` 
         LEFT OUTER JOIN (`module_has_competence` AS 
                         `competence.module_has_competence` 
                          INNER JOIN `competence` AS `competence` 
                                  ON `competence`.`id` = 
  `competence.module_has_competence`.`module_id`) 
  ON `module`.`id` = 
  `competence.module_has_competence`.`competence_id` 
  WHERE  `module`.`id` = 1; 

据我了解，.hasMany 引用了 1:M 关系，它不需要连接表。

http://docs.sequelizejs.com/en/latest/docs/associations/#one-to-many-associations

这是我得出这个结论的要点：

https://gist.github.com/sjlu/fa5c2e0e267cd692418a

【参考方案2】：

史蒂文的回答对我不起作用，但切换了外键。

Competence.belongsToMany(Module, 
  through: Module_has_competence,
  as: 'module',
  foreignKey: 'competence_id'
);
Module.belongsToMany(Competence, 
  through: Module_has_competence,
  as: 'competence',
  foreignKey: 'module_id'
);