update

models/VocabRelation.js

@@ -0,0 +1,65 @@
+const { DataTypes } = require('sequelize');
+const { sequelize } = require('../config/database');
+
+const VocabRelation = sequelize.define('VocabRelation', {
+    relation_id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true,
+      comment: 'Unique identifier for vocabulary relation'
+    },
+    vocab_id: {
+      type: DataTypes.UUID,
+      allowNull: false,
+      references: {
+        model: 'vocab',
+        key: 'vocab_id'
+      },
+      onDelete: 'CASCADE',
+      comment: 'Reference to vocabulary entry'
+    },
+    relation_type: {
+      type: DataTypes.ENUM('synonym', 'antonym', 'related'),
+      allowNull: false,
+      comment: 'Type of relation (synonym, antonym, related)'
+    },
+    related_word: {
+      type: DataTypes.STRING(100),
+      allowNull: false,
+      comment: 'The related word (e.g., consume, dine, fast)'
+    },
+    related_vocab_id: {
+      type: DataTypes.UUID,
+      references: {
+        model: 'vocab',
+        key: 'vocab_id'
+      },
+      onDelete: 'SET NULL',
+      comment: 'Reference to related vocab entry if it exists in system'
+    },
+    created_at: {
+      type: DataTypes.DATE,
+      defaultValue: DataTypes.NOW
+    }
+  }, {
+    tableName: 'vocab_relation',
+    timestamps: true,
+    createdAt: 'created_at',
+    updatedAt: false,
+    indexes: [
+      {
+        name: 'idx_vocab_relation_vocab',
+        fields: ['vocab_id']
+      },
+      {
+        name: 'idx_vocab_relation_type',
+        fields: ['relation_type']
+      },
+      {
+        name: 'idx_vocab_relation_related',
+        fields: ['related_vocab_id']
+      }
+    ]
+  });
+
+module.exports = VocabRelation;