Egg中使用mysql

1、安装egg-mysql

npm i egg-mysql --save

2、配置插件

// config/plugin.js
'use strict';
exports.mysql = {
    enable: true,
    package: 'egg-mysql',
};

3、数据库连接配置

// config/config.default.js

'use strict';

module.exports = appInfo => {

  const config = exports = {};

  config.mysql = {
    client: {
      host: 'localhost',
      port: '3306',
      user: 'root',
      password: '123456',
      database: 'test',
    },
    app: true,        // 是否加载到 app 上，默认开启
    agent: false,    // 是否加载到 agent 上，默认关闭
  };

  return {
    ...config
  };

};

4、增、删、改、查操作

//查询一条数据，提到一个json对象{}
let result = await this.app.mysql.get("user",{id:1});

//查询多条数据，返回一个json数组[]
let result = await this.app.mysql.select(
    "user",
    {
        where:{id:1}
    }
);

//追加数据记录
let result = await this.app.mysql.insert(
    "user",
    {username:"lisi",password:"1234"}
);

//更新数据 （按主键进行更新）
let result = await this.app.mysql.update('user',{ id:2, username:'赵四' });
//更新数据 通过 sql 语句
let results=await this.app.mysql.query(
    'update user set username = ? where id = ?',
    ["王五",2]
);

//删除数据
let result= await this.app.mysql.delete('user',{ id:3 });

//执行SQL
this.app.mysql.query(sql,values);

5、事务处理

var conn = await this.app.mysql.beginTransaction();
try{
    await conn.query("delete from fee_borrow_bill where borrow_bill_code=?",[borrow_bill_code]);
    await conn.query("delete from fee_borrow_bill_item where borrow_bill_code=?",[borrow_bill_code]);
    await conn.commit();
    return "ok";
}catch(err){
    await conn.rollback();
    return "数据库操作异常，请联系管理员！ ";
}

6、多数据库操作

// 配置
exports.mysql = {
  clients: {
    db1: {
      host: 'mysql.com',
      port: '3306',
      user: 'test_user',
      password: 'test_password',
      database: 'test',
    },
    // ...
  },
  // default configuration for all databases
  default: {

  },

  // load into app, default is open
  app: true,
  // load into agent, default is close
  agent: false,
};

//使用
const client1 = app.mysql.get('db1');
client1.query(sql, values);

const client2 = app.mysql.get('db2');
client2.query(sql, values);