sequelize

sequelize 是Node.js中应用最广泛的orm开源库，github：https://github.com/sequelize/sequelize。
中文文档：https://github.com/demopark/sequelize-docs-Zh-CN
Sequelize 是一个基于 promise 的 Node.js ORM, 目前支持 Postgres, MySQL, SQLite 和 Microsoft SQL Server. 它具有强大的事务支持, 关联关系, 读取和复制等功能.
按照官方文档做，总是觉得不对劲，做的非常累，总有劳动力没有解放的感觉。后来发现这个库还有两个关键的配套工具sequelize-cli，和sequelize-auto。
sequelize-cli用来通过命令产生对应的代码模型和数据库迁移。
sequelize-auto 用来通过已有的数据库结构生成代码模型和数据库迁移。
常用命令

sequelize-auto -h localhost -d login_demo -u root -x root -p 3306 -t user

Options:
  -h, --host        IP/Hostname for the database.   [required]
  -d, --database    Database name.                  [required]
  -u, --user        Username for database.
  -x, --pass        Password for database.
  -p, --port        Port number for database.
  -c, --config      JSON file for Sequelize's constructor "options" flag object as defined here: https://sequelize.readthedocs.org/en/latest/api/sequelize/
  -o, --output      What directory to place the models.
  -e, --dialect     The dialect/engine that you're using: postgres, mysql, sqlite
  -a, --additional  Path to a json file containing model definitions (for all tables) which are to be defined within a model's configuration parameter. For more info: https://sequelize.readthedocs.org/en/latest/docs/models-definition/#configuration
  -t, --tables      Comma-separated names of tables to import
  -T, --skip-tables Comma-separated names of tables to skip
  -C, --camel       Use camel case to name models and fields
  -n, --no-write    Prevent writing the models to disk.
  -s, --schema      Database schema from which to retrieve tables

node_modules/.bin/sequelize model:generate --name User --attributes firstName:string,lastName:string,email:string
node_modules/.bin/sequelize db:migrate
node_modules/.bin/sequelize db:migrate:undo

经过测试 这两命令不能看做互逆操作。如何处理自己看着办吧。