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Mysql 如何在相关表中添加子行？？（续N:M关系）

mysql node.js express sequelize.js

Mysql 如何在相关表中添加子行？？（续N:M关系）,mysql,node.js,express,sequelize.js,Mysql,Node.js,Express,Sequelize.js,在我的程序中，我想创建一个名为Column的新帖子，它包含许多分类。而且，一个类别可以包含许多帖子 所以我尝试在帖子中添加一个类别，但失败了。下面是我尝试过的代码：但是，没有错误输出到日志中 for(var i in column_categorys) { const category = await Category.findOrCreate({ where : { category_name: column_categorys[i], }

在我的程序中，我想创建一个名为Column的新帖子，它包含许多分类。而且，一个类别可以包含许多帖子

所以我尝试在帖子中添加一个类别，但失败了。下面是我尝试过的代码：但是，没有错误输出到日志中

for(var i in column_categorys) {
    const category = await Category.findOrCreate({
      where : {
        category_name: column_categorys[i],
      }
    })
    .then(resolve => {
      return resolve;
    })
    .catch(function(error) {
      isFail = true;
      return null;
    });

    await column.addCategory(
      category.id,
      { through:
        { selfGranted: false }
      }
    )
    .catch(err => {
      console.log(err);
    });
  }
column_info.js

const Sequelize = require('sequelize');

module.exports = class Column extends Sequelize.Model {
  static init(sequelize) {
    return super.init({
      column_title: {
        type: Sequelize.STRING(200),
        allowNull: false,
        unique: true,
      },
      column_content_text: {
        type: Sequelize.STRING(10000),
        allowNull: false,
      },
      column_content_html: {
        type: Sequelize.STRING(10000),
      },
      column_thumbnail_url: {
        type: Sequelize.STRING(300),
      },
    }, {
      sequelize,
      timestamps: true,
      underscored: true,
      modelName: 'Column',
      tableName: 'columns',
      paranoid: true,
      charset: 'utf8',
      collate: 'utf8_general_ci',
    });
  }

  static associate(db) {
    db.Column.belongsToMany(db.Category, {
      through: 'ColumnCategory',
      unique: false,
    });
    db.Column.belongsToMany(db.Tag, {
      through: 'ColumnTag',
      unique: false,
    });
  }
};
category_info.js

const Sequelize = require('sequelize');

module.exports = class Category extends Sequelize.Model {
  static init(sequelize) {
    return super.init({
      category_name: {
        type: Sequelize.STRING(50),
        allowNull: false,
        unique: true,
      },
    }, {
      sequelize,
      timestamps: false,
      underscored: true,
      modelName: 'Category',
      tableName: 'categorys',
      paranoid: false,
      charset: 'utf8',
      collate: 'utf8_general_ci',
    });
  }

  static associate(db) {
    db.Category.belongsToMany(db.Column, {
      through: 'ColumnCategory',
      unique: false,
    });
  }
};
model/index.js

const Sequelize = require('sequelize');
const User = require('./user');
const Baby = require('./baby_info');
const UserCase = require('./user_case');
const Column = require('./column_info');
const Tag = require('./tag_info');
const Category = require('./category_info');

const env = process.env.NODE_ENV || 'development';
const config = require(__dirname + '/../config/config')[env];
const db = {};

const sequelize = new Sequelize(config.database, config.username, config.password, config);

db.sequelize = sequelize;

db.User = User;
db.Baby = Baby;
db.UserCase = UserCase;
db.Column = Column;
db.Tag = Tag;
db.Category = Category;

User.init(sequelize);
Baby.init(sequelize);
UserCase.init(sequelize);
Column.init(sequelize);
Tag.init(sequelize);
Category.init(sequelize);

User.associate(db);
Baby.associate(db);
UserCase.associate(db);
Column.associate(db);
Tag.associate(db);
Category.associate(db);

module.exports = db;
你能告诉我这段代码的哪一部分我用错了关系查询吗

最新版本 响应代码为400，没有错误消息。但是
列类别中没有任何内容

下一个是日志消息


0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): START TRANSACTION;
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): INSERT INTO `columns` (`id`,`column_title`,`column_content_text`,`column_content_html`,`column_thumbnail_url`,`created_at`,`updated_at`) VALUES (DEFAULT,?,?,?,?,?,?);
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SAVEPOINT `9904bd92-1a06-4f58-853f-9517d560ca50-sp-1`;
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SELECT `id`, `category_name` FROM `categorys` AS `Category` WHERE `Category`.`category_name` = 'category1';
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SAVEPOINT `9904bd92-1a06-4f58-853f-9517d560ca50-sp-2`;
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SELECT `id`, `category_name` FROM `categorys` AS `Category` WHERE `Category`.`category_name` = 'category2';
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SAVEPOINT `9904bd92-1a06-4f58-853f-9517d560ca50-sp-3`;
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SELECT `id`, `tag_name` FROM `tags` AS `Tag` WHERE `Tag`.`tag_name` = 'tag1' LIMIT 1;
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SAVEPOINT `9904bd92-1a06-4f58-853f-9517d560ca50-sp-4`;
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SELECT `id`, `tag_name` FROM `tags` AS `Tag` WHERE `Tag`.`tag_name` = 'tag2' LIMIT 1;
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): COMMIT;
0|app  | 21-01-03 11:27:28: POST /api/column 200 55.857 ms - 73



您不应将
then/catch
与
wait
一起使用，而应使用
try/catch
捕获任何错误：


试试看{
对于（列类别的列类别）{
const category=等待category.findOrCreate({
其中：{
类别名称：列类别[i]，
}
})
wait column.addCategory(
类别id，
{通过：
{自授予：false}
}
);
}
}捕捉（错误）{
控制台日志（err）；
}


此外，我建议在执行多个CRUD操作时使用事务。这样，修改后的数据将保持一致。
这可以通过以下方式实现：


wait-sequelize.transaction（异步事务=>{
试一试{
对于（列类别的列类别）{
const category=等待category.findOrCreate({
其中：{
类别名称：列类别[i]，
},
交易
})
wait column.addCategory(
类别id，
{通过：
{自授予：false}，
交易
}
);
}
}捕捉（错误）{
控制台日志（err）；
}
});

麻烦制造者被找到了

它返回对象，布尔值（表示创建了新行）

因此，结果必须分为两个变量

比如说,


const[category，created]=wait category.findOrCreate（）

在最新版本中修复此部件后，工作正常


当然，addCategory（category），addCategory（category.id）这两种方法都有效
 评论不用于扩展讨论；这段对话已经结束。

0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): START TRANSACTION;
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): INSERT INTO `columns` (`id`,`column_title`,`column_content_text`,`column_content_html`,`column_thumbnail_url`,`created_at`,`updated_at`) VALUES (DEFAULT,?,?,?,?,?,?);
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SAVEPOINT `9904bd92-1a06-4f58-853f-9517d560ca50-sp-1`;
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SELECT `id`, `category_name` FROM `categorys` AS `Category` WHERE `Category`.`category_name` = 'category1';
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SAVEPOINT `9904bd92-1a06-4f58-853f-9517d560ca50-sp-2`;
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SELECT `id`, `category_name` FROM `categorys` AS `Category` WHERE `Category`.`category_name` = 'category2';
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SAVEPOINT `9904bd92-1a06-4f58-853f-9517d560ca50-sp-3`;
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SELECT `id`, `tag_name` FROM `tags` AS `Tag` WHERE `Tag`.`tag_name` = 'tag1' LIMIT 1;
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SAVEPOINT `9904bd92-1a06-4f58-853f-9517d560ca50-sp-4`;
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): SELECT `id`, `tag_name` FROM `tags` AS `Tag` WHERE `Tag`.`tag_name` = 'tag2' LIMIT 1;
0|app  | 21-01-03 11:27:28: Executing (9904bd92-1a06-4f58-853f-9517d560ca50): COMMIT;
0|app  | 21-01-03 11:27:28: POST /api/column 200 55.857 ms - 73