app2-api/modules/blog/post-category.model.js

module.exports = function (sequelize, DataTypes) {
	const PostCategory = sequelize.define('PostCategory', {
	    postId: {
			type: DataTypes.UUID,
	        primaryKey: true,
	        foreignKey: true
	    },
	    categoryId: {
			type: DataTypes.INTEGER,
	        primaryKey: true,
	        foreignKey: true
	    }
	}, {
		tableName: 'post_category',
		freezeTableName: true,
		timestamps: false
	});

	return PostCategory;
};