Sequelize: many-to-many relationship to self, through another table?-CodePudding

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Here is my best attempt so far. The following code creates the table columns OK, but does not create the rows as expected. The create method may be totally wrong; for example, there should be a way to set predicate, but I don't know where to put it:

const { Sequelize } = require("sequelize"); (async () => { try { const db = await new Sequelize({ dialect: "sqlite", storage: "./db/db.db", }); const Node = await db.define("node", { name: { type: Sequelize.STRING, }, }); const Edge = await db.define("edge", { subject_node_id: { type: Sequelize.INTEGER, }, predicate: { type: Sequelize.STRING, }, direct_object_node_id: { type: Sequelize.INTEGER, }, }); await Node.sync({ force: true }); await Edge.sync({ force: true }); await Node.belongsToMany(Node, { through: "Edge", as: "subjects", foreignKey: "id", otherKey: "subject_node_id" }); await Node.belongsToMany(Node, { through: "Edge", as: "direct_objects", foreignKey: "id", otherKey: "direct_object_node_id" }); await Node.create( { name: "Dave", // Loves ?? subjects: [{ name: "Sarah" }] }, ); console.log("created"); } catch (error) { console.error(error); } })();

I did find this SO thread, but the accepted answer doesn't quite get there. Any additional ideas? Thanks.

CodePudding user response：

I figured it out:

const { Sequelize, DataTypes } = require("sequelize"); (async () => { try { const db = await new Sequelize({ dialect: "sqlite", storage: "./db/db.db", }); const Node = db.define("node", { name: DataTypes.STRING, }); const Edge = db.define("edge", { subjectId: DataTypes.INTEGER, predicate: DataTypes.STRING, dobjectId: DataTypes.INTEGER, }); await Node.belongsToMany(Node, { through: Edge, as: "subjects", foreignKey: "dobjectId", }); await Node.belongsToMany(Node, { through: Edge, as: "dobjects", foreignKey: "subjectId", }); await db.sync({force: true}); const dave = await Node.create({ name: "Dave" }); const sarah = await Node.create({ name: "Sarah" }); await dave.addDobject(sarah, { through: { predicate: "Loves" }}); await sarah.addDobject(dave, { through: { predicate: "Loves" }}); const result = await Node.findOne({ where: { name: "sarah" }, include: ["subjects", "dobjects"], }); console.log(result); console.log("created"); } catch (error) { console.error(error); } })();