使用n:m和1:m关联续订删除实例并更新Model

我的postgresql数据库中有2个模型,并使用sequelize和node:

用户

交易

并且像这样关联:

UserModel.hasMany(TransactionModel, { as: 'sentTransactions', foreignKey: 'senderId' });
UserModel.hasMany(TransactionModel, { as: 'receivedTransactions', foreignKey: 'receiverId' });
UserModel.belongsToMany(TransactionModel, { as: 'transactionLikes', through: 'UserLike', foreignKey: 'userId' });
TransactionModel.belongsTo(UserModel, { as: 'receiver' });
TransactionModel.belongsTo(UserModel, { as: 'sender' });
TransactionModel.belongsToMany(UserModel, { as: 'likers', through: 'UserLike', foreignKey: 'transactionId' });

这意味着用户有许多收到和发送的交易,每个用户可以"喜欢"许多交易.

如何删除事务并删除所有关联(接收者,发件人,liker)？我也不想删除用户.

我还想更新这样定义的用户模型,以便添加"email"属性:

const UserModel = db.define('user', {
   id: { type: Sequelize.STRING, unique: true, primaryKey: true },
   firstName: { type: Sequelize.STRING  },
   lastName: { type: Sequelize.STRING },
   username: {
    type: Sequelize.STRING,
    unique: {
    args: true,
    msg: USERNAME_IS_TAKEN,
   },
 }

我该如何更新模型？现有实例会发生什么？

预先感谢您的帮助!