如何在 NodeJS 中使用 Sequelize 执行三个 table 连接

Question

我正在尝试使用 Sequelize ORM 创建一个 3 table 连接。我目前开发的代码是

    const sequelize = DB.GetDB(DB.reports);
    const rptDB = rpts.initModels(sequelize);

    rptDB.tblReportHeadings.hasMany(rptDB.tblReports, { foreignKey: rptDB.tblReports.id, targetKey: rptDB.tblReportHeadings.Report })
//Error points to Report on this next row
    rptDB.tblReports.belongsTo(rptDB.tblReportHeadings, { foreignKey: rptDB.tblReportHeadings.Report, targetKey: rptDB.tblReports.id });

    rptDB.tblReportHeadings.hasMany(rptDB.tblHeadings, { foreignKey: rptDB.tblHeadings.id, targetKey: rptDB.tblReportHeadings.Heading })
    rptDB.tblHeadings.belongsTo(rptDB.tblReportHeadings, { foreignKey: rptDB.tblReportHeadings.Heading, targetKey: rptDB.tblHeadings.id });

    rptDB.tblAccess.hasMany(rptDB.tblHeadings, { foreignKey: Heading, targetKey: id });
    rptDB.tblHeadings.belongsTo(rptDB.tblAccess, { foreignKey: id, targetKey: Heading })

    let ret = tblReports.findAll({
        attributes: [
            id, reportTitle
        ],
        include: [{
            model: rptDB.tblHeadings,
            attributes: [Heading]
        },
        {
            model: rptDB.tblAccess,
            where: { accessLevel: roles }
        }
        ],
        logging: (sql) => console.log(sql)
    });

但我不断收到指向第一个 belongsTo.

的“报告未定义”错误

table 定义是使用 sequelize-auto 创建的，我已验证 tblReportHeadings 具有报告字段。

以下是 3 个相关 table 的定义：

tblReportHeadings

const Sequelize = require('sequelize');
module.exports = function(sequelize, DataTypes) {
  return sequelize.define('tblReportHeadings', {
    id: {
      autoIncrement: true,
      type: DataTypes.INTEGER,
      allowNull: false,
      primaryKey: true
    },
    Report: {
      type: DataTypes.INTEGER,
      allowNull: true
    },
    Heading: {
      type: DataTypes.INTEGER,
      allowNull: true
    }
  }, {
    sequelize,
    tableName: 'tblReportHeadings',
    schema: 'dbo',
    timestamps: false,
    indexes: [
      {
        name: "PK_tblReportHeadings",
        unique: true,
        fields: [
          { name: "id" },
        ]
      },
    ]
  });
};

tblHeadings

const Sequelize = require('sequelize');
module.exports = function(sequelize, DataTypes) {
  return sequelize.define('tblHeadings', {
    id: {
      autoIncrement: true,
      type: DataTypes.INTEGER,
      allowNull: false,
      primaryKey: true
    },
    Heading: {
      type: DataTypes.STRING(100),
      allowNull: true
    }
  }, {
    sequelize,
    tableName: 'tblHeadings',
    schema: 'dbo',
    timestamps: false,
    indexes: [
      {
        name: "PK_tblHeadings",
        unique: true,
        fields: [
          { name: "id" },
        ]
      },
    ]
  });
};

tblAccess

const Sequelize = require('sequelize');
module.exports = function(sequelize, DataTypes) {
  return sequelize.define('tblAccess', {
    id: {
      autoIncrement: true,
      type: DataTypes.INTEGER,
      allowNull: false,
      primaryKey: true
    },
    Heading: {
      type: DataTypes.INTEGER,
      allowNull: true
    },
    accessLevel: {
      type: DataTypes.STRING(40),
      allowNull: true
    }
  }, {
    sequelize,
    tableName: 'tblAccess',
    schema: 'dbo',
    timestamps: false,
    indexes: [
      {
        name: "PK_tblAccess",
        unique: true,
        fields: [
          { name: "id" },
        ]
      },
    ]
  });
};

我确定问题在于我如何创建连接，但作为 Sequelize 的新手，我不确定问题出在哪里。

我试图完成的查询是这样的：

`SELECT     DISTINCT tblReports.id, tblReports.reportTitle, tblHeadings.Heading
    FROM         tblReports INNER JOIN
                  tblReportHeadings ON tblReports.id = tblReportHeadings.Report INNER JOIN
                  tblHeadings ON tblReportHeadings.Heading = tblHeadings.id INNER JOIN
                  tblAccess ON tblHeadings.id = tblAccess.Heading
    WHERE     (LOWER(tblAccess.accessLevel) IN (${roles.join(',')}))
    ORDER BY tblReports.reportTitle`

Answer 1

所以我遇到的问题不是通过更改上面的代码而是通过下面编写的连接代码得到纠正的：

rptDB.tblAccess.hasMany(rptDB.tblHeadings, { foreignKey: Heading, targetKey: id });
    rptDB.tblHeadings.belongsTo(rptDB.tblAccess, { foreignKey: id, targetKey: Heading })

必须改为

rptDB.tblAccess.hasMany(rptDB.tblHeadings, { foreignKey: rptDB.tblAccess.Heading, targetKey: rptDB.tblHeadings.id });
    rptDB.tblHeadings.belongsTo(rptDB.tblAccess, { foreignKey: rptDB.tblHeadings.id, targetKey: rptDB.tblAccess.Heading })

为了工作。

此代码仍然存在多个问题，但这是针对此特定错误消息的解决方案。确保完全限定每个 table 在这里似乎是必不可少的，并且假设 Sequelize 会捡起碎片（有时会这样做）走捷径是不可靠的。

如何在 NodeJS 中使用 Sequelize 执行三个 table 连接

How to perform a three table join using Sequelize in NodeJS

node.js

sequelize.js