sequelize-cli的使用

0. 初始化项目

npm init

1. 安装 sequelize-cli

安装
npm install --save sequelize-cli sequelize mysql2
如果是postgreps 则安装 pg pg-store

2. 生成 sequelize 目录

node_modules/.bin/sequelize init

执行上面命令，会生成以下几个文件夹：

config：包含一个 config.json 文件
models：包含一个 index.js 文件
migrations：空文件夹
seeders：空文件夹

3. 配置连接数据库的信息

{
  "development": {
    "username": "root",
    "password": "123456",
    "database": "database_development",
    "host": "127.0.0.1",
    "dialect": "mysql"
  },
  "test": {
    "username": "root",
    "password": "123456",
    "database": "database_test",
    "host": "127.0.0.1",
    "dialect": "mysql"
  },
  "production": {
    "username": "root",
    "password": "123456",
    "database": "database_production",
    "host": "127.0.0.1",
    "dialect": "mysql"
  }
}
password 字段是字符串类型，切勿设置为数字类型

4. 创建数据库

node_modules/.bin/sequelize db:create

5. 生成模型文件和迁移文件

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

执行上面命令会：

在 models 文件夹里生成一个 user.js 文件
在 migrations 文件夹里生成一个 20190210132709-create-user.js 文件

6. 执行迁移

node_modules/.bin/sequelize db:migrate

7. 生成种子文件

node_modules/.bin/sequelize seed:generate --name demo-user

8. 执行种子文件

node_modules/.bin/sequelize db:seed:all

这里的模型和迁移文件都可以自动手动编写， 模型用于程序使用 迁移和种子文件用于生成数据库结构表和初始化数据使用
一对一，一对多的关系也是在模型中指定的
也可以通过npm install sequelize-cli -g 全局安装 然后sequelize 来执行上述命令

相关命令

  sequelize db:migrate                        Run pending migrations
  sequelize db:migrate:schema:timestamps:add  Update migration table to have timestamps
  sequelize db:migrate:status                 List the status of all migrations
  sequelize db:migrate:undo                   Reverts a migration
  sequelize db:migrate:undo:all               Revert all migrations ran
  sequelize db:seed                           Run specified seeder
  sequelize db:seed:undo                      Deletes data from the database
  sequelize db:seed:all                       Run every seeder
  sequelize db:seed:undo:all                  Deletes data from the database
  sequelize db:create                         Create database specified by configuration
  sequelize db:drop                           Drop database specified by configuration
  sequelize init                              Initializes project
  sequelize init:config                       Initializes configuration
  sequelize init:migrations                   Initializes migrations
  sequelize init:models                       Initializes models
  sequelize init:seeders                      Initializes seeders
  sequelize migration:generate                Generates a new migration file       [aliases: migration:create]
  sequelize model:generate                    Generates a model and its migration  [aliases: model:create]
  sequelize seed:generate                     Generates a new seed file            [aliases: seed:create]

断开数据库的链接

SELECT pg_terminate_backend(pg_stat_activity.pid)
FROM pg_stat_activity
WHERE datname='testdb' AND pid<>pg_backend_pid();