将SQL查询转换为Sequelize ORM会返回不需要的结果

Question

我是Sequelize的初学者和ORM的概念。我已成功将查询转换为Sequelize findAll（）函数，但它返回不需要的结果。 PostgreSQL查询可以正常工作并返回结果。

有关系的表：

1. 作家（writerId PK，writerName）
2. 帖子（postId PK，postTitle，postDescription）
3. skillmatrix（skillmatrixId PK，writerId FK，postId FK，writerSkill）

我的查询：

SELECT writers."writerName", posts."postTitle", posts."postDescription", 
skillmatrix.* 
FROM writers
INNER JOIN skillmatrix
      ON writers."writerId" = skillmatrix."writerId"
INNER JOIN posts
      ON skillmatrix."postId" = posts."postId"
      ORDER BY writers."writerId", posts."postId"

SQL Query的输出：

Sequelize中的关系：

db.skillmatrix.hasMany(db.posts,{foreignKey: 'postId'});
db.skillmatrix.hasMany(db.writers,{foreignKey: 'writerId'});

Sequelize中的findAll（）方法：

exports.findAll = (req, res, next) => {
SkillMatrix.findAll({
    include: [
        {
            model: Writer,
            required: true
        },
        {
            model: Post, 
            required: true
        }
    ],
    order:[
        ['"writerId"', 'ASC'],
        ['"postId"', 'ASC']
    ]
})
.then(skillmatrix => {
    res.status(200).json(skillmatrix);
})
.catch(err => {
    console.log(err);
    res.status(500).json({msg: "error", details: err});
});
};

Sequelize的JSON输出：

{
    "skillMatrixId": 1,
    "writerId": 1,
    "postId": 1,
    "writerSkill": "None",
    "writers": [
        {
            "writerId": 1,
            "writerName": "Writer1"
        }
    ],
    "posts": [
        {
            "postId": 1,
            "postTitle": "Post1"
            "postDescription": "This is Post1"
        }
    ]
},
{
    "skillMatrixId": 2,
    "writerId": 1,
    "postId": 2,
    "writerSkill": "SEO",
    "writers": [
        {
            "writerId": 2,
            "writerName": "Writer2"  //This is unexpected
        }
    ],
    "posts": [
        {
            "postId": 2,
            "postTitle": "Post2",
            "postDescription": "This is Post2"
        }
    ]
},
{
    "skillMatrixId": 3
    "writerId": 1,
    "postId": 3,
    "writerSkill": "Proofread"
    "writers": [
        {
            "writerId": 3,  //Unexpected
            "writerName": "Writer3" 
        }
    ],
    "posts": [
        {
            "postId": 3,
            "postTitle": "Post3",
            "postDescription": "This is Post3"
        }
    ]
}...

请告诉我，我做错了什么。还建议我一些很好的资源，我可以深入了解这一点。谢谢。

编辑：

Sequelize日志查询：

SELECT "skillmatrix"."skillMatrixId", 
"skillmatrix"."writerId", "skillmatrix"."postId",
"skillmatrix"."writerSkill", 
"writers"."writerId" AS "writers"."writerId",  
"writers"."writerName" AS "writers"."writerName", 
"posts"."postId" AS "posts"."postId", 
"posts"."postTitle" AS "posts"."postTitle", 
"posts"."postDescription" AS "posts"."postDescription", 
"posts"."writerId" AS "posts"."writerId"
FROM "skillmatrix" AS "skillmatrix" 
INNER JOIN "writers" AS "writers" ON "skillmatrix"."skillMatrixId" = 
"writers"."writerId" 
INNER JOIN "posts" AS "posts" ON "skillmatrix"."skillMatrixId" = 
"posts"."postId" 
ORDER BY "skillmatrix"."writerId" ASC, "skillmatrix"."postId" ASC

Answer 1

更新Sequelize关系：

db.skillmatrix.hasMany(db.posts,{foreignKey: 'postId'});
db.skillmatrix.hasMany(db.writers,{foreignKey: 'writerId'});

至：

db.skillmatrix.hasMany(db.posts,{sourceKey: 'postId' , foreignKey: 'postId'});
db.skillmatrix.hasMany(db.writers,{sourceKey: 'writerId' ,foreignKey: 'writerId'});

Answer 2

首先，您应该检查sequelize日志 - 您的findAll生成什么查询？我猜它正在加入一个错误的领域。

Sequelize为多对多关系提供了一些选择。你可以试试：

db.posts.belongsToMany  (db.writers, {as : 'p2w', through: db.skillMatrix, foreignKey: 'postId'   });
db.writers.belongsToMany(db.posts,   {as : 'w2p', through: db.skillMatrix, foreignKey: 'writerId' });

db.posts.findAll({
  include: { 
     model: db.writers, 
     as: 'p2w',
     required: true
   }
});

我接近语法 - 在doc：belongsToMany中查看它

编辑 - 您现有的关联可以修复如下：

db.skillmatrix.hasMany(db.writers,{sourceKey: 'writerId', foreignKey: 'writerId'});

但是，请记住未来任务的M：M选项:)