重拾koa2之数据库_mysql

const mysql  = require('mysql')
const connection = mysql.createConnection({
    host:'127.0.0.1',
    user:'root',
    password:'guilong',
    database:'koatest'
})

// 执行sql脚本对数据库进行读写
connection.query('SELECT * FROM my_table',(error,results,fields)=>{
    if(error) throw error

    connection.release()
})

const mysql = require('mysql')

//创建数据池
const pool = mysql.createPool({
    host:'127.0.0.1',
    user:'root',
    password:'123456',
    database:'koatest'
})

//在数据池中进行会话操作
pool.getConnection(function(err,connection){
    connection.query('SELECT * FROM my_table',(error,results,fields)=>{
        //结束会话
        connection.release()
        //如果有错误就抛出
        if(error) throw error
    })
})

const mysql = require('mysql')

const pool = mysql.createPool({
    host:'127.0.0.1',
    user:'root',
    password:'123456',
    database:'koatest'
})

let query = function(sql,values){
    return new Promise((resolve,reject)=>{
       pool.getConnection(function(err,connection){
           if(err){
               reject(err)
           }else{
               connection.query(sql.values,(err,rows)=>{
                   if(err){
                       reject(err)

                   }else{
                       resolve(rows)
                   }
                   connection.release()
               })
           }
       })
    })
}

module.exports = {query}

const {query} = require('./asyncsql')
async function selectAllData(){
    let sql = 'SELECT * FROM my_table'
    let dataList = await query(sql)
    return dataList
}

async function getData(){
    let dataList =await selectAllData()
    console.log(dataList)
}

getData()