Question

我正在创建一个电影应用程序。我已经在mySql上对数据库建模，但是在将其迁移到Sequelize时遇到了麻烦。我已经按照文档进行操作，但是却遇到许多不同的错误。

我尝试使用关联和索引（应该如此）。 This is the model I am trying to make。

OCCUPIED_SEATS仅由两个外键组成，并且都构成唯一索引。

OCCUPIED_SEATS ：

const SEATS = require("./Seats");
const SCREENING = require("./Screening");

const OCCUPIED_SEATS = sequelize.define("OCCUPIED_SEATS", {
    //SEATS_ID
    //SCREENING_ID
  },
  {
    indexes: [
      {
        unique: true,
        fields: [SEAT_ID, SCREENING_ID]
      }
    ],
    underscored: true
  }
);

module.exports = OCCUPIED_SEATS;

座位：

const OCCUPIED_SEATS = require("./Occupied_Seats");

const SEATS = sequelize.define("SEATS", {
    SEATS_ID: {       
      type: Sequelize.INTEGER,
      primaryKey: true,
      allowNull: false,
      autoIncrement: true
    },
    ROW: {
        type: Sequelize.STRING,
        allowNull: false,
    },
    COLUMN: {
        type: Sequelize.INTEGER,
        allowNull: false
    },
  },
  {
    underscored: true
  }
);

SEATS.hasMany(OCCUPIED_SEATS, {foreignKey: 'SEAT_ID'})

module.exports = SEATS;

筛选：

const OCCUPIED_SEATS = require("./Occupied_Seats");

const SCREENING = sequelize.define("SCREENING", {
    SCREENING_ID: {
      type: Sequelize.INTEGER,
      primaryKey: true,
      allowNull: false,
      autoIncrement: true
    },
    SCREENING_START_TIME: {
        type: Sequelize.TIME,
        allowNull: false,
    },
    DATE: {
        type: Sequelize.DATE,
        allowNull: false
    }
  },
  {
    underscored: true,
    indexes: [
      {
        unique: true,
        fields: [ROOM_ID, SCREENING_START_TIME, DATE]
      }
    ]
  }
);

SCREENING.hasMany(OCCUPIED_SEATS, {foreignKey: 'SCREENING_ID'});

module.exports = SCREENING;

尝试此操作时遇到的错误是：

[?] Error: SEATS.hasMany called with something that's not a subclass of Sequelize.Model

我应该如何编码模型？

Answer 1

就像新版本的Sequelize中一样，您必须通过Sequelize.Model类型定义模型：

class Seats extends Sequelize.Model {}
Seats.init({
    id: {       
      type: Sequelize.INTEGER,
      primaryKey: true,
      allowNull: false,
      autoIncrement: true
    },
    row: {
      type: Sequelize.STRING,
      allowNull: false,
    },
   ...
});
module.exports = Seats;

然后在其他地方：

Seats.hasMany(OccupiedSeatc, {foreignKey: 'SEAT_ID'})

请参见model definition docs和accociation docs。

在续集中编码弱实体时出现问题

1 个答案: