连接数据库
初级菜鸟，为图方便暂时在路由中配置数据库未使用连接池 ，路由文件
const mysql = require('mysql') //引入数据库插件
const koaRouter = require('koa-router');
const router = koaRouter();
//连接数据库
const connection = mysql.createConnection({
host: 'localhost',
user: 'root',
password: '123456',
port: '3306',
database: 'testnode'
})
//新增数据
router.post('/add', async (ctx, next) => {
console.log(Boolean( ctx.request.query.name && ctx.request.query.address && ctx.request.query.phone))
if(ctx.request.query.phone && ctx.request.query.address && ctx.request.query.name){
var data = {
}
var createdTime=new Date()
var querySql="INSERT INTO address (createdTime,name,address,phone,belongsId) VALUES(?,?,?,?,?)"
var queryParams=[createdTime,ctx.request.query.name,ctx.request.query.address,ctx.request.query.phone,ctx.request.query.userId]
console.log(queryParams)
var searchSql = (querySql,queryParams) => {
return new Promise((resolve, reject) => {
console.log('准备查询')
connection.query(querySql,queryParams, function(err, result) {
if(err){
reject(0)
console.log(err+'err')
}
resolve(result)
})
})
}
var res= await searchSql(querySql,queryParams)
if(res){
data.code='0'
data.msg="添加成功"
ctx.body=data
}else{
data.code='1'
data.msg="添加失败"
ctx.body=data
}
}
});
//查询数据
router.get('/query', async (ctx, next) => {
var data = {
}
console.log(ctx.request.query.pageNo - 1)
var querySql="SELECT * FROM address where belongsId= '"+ctx.request.query.userId+"' limit "+ (ctx.request.query.pageNo-1)*ctx.request.query.pageSize+"," + ctx.request.query.pageSize
var querySqlNo="SELECT * FROM address where belongsId= '"+ctx.request.query.userId+"'"
var searchSql = (thesql) => {
return new Promise((resolve, reject) => {
console.log('准备查询')
connection.query(thesql, function(err, result) {
if(err){
reject(0)
console.log(err+'err')
}
resolve(result)
})
})
}
var res= await searchSql(querySqlNo)
if(res){
var datares= await searchSql(querySql)
if(datares){
var param={
list:datares,total:res.length}
data.code='0'
data.msg="成功获取"
data.data=param
ctx.body=data
}
}
})
//更新数据
router.post('/update', async (ctx, next) => {
var updateSql="UPDATE address SET name = '"+ctx.request.query.name+"', phone = '" + ctx.request.query.phone + "', address = '" + ctx.request.query.address +"' where id = '" +ctx.request.query.id + "'"
var searchSql = (thesql) => {
return new Promise((resolve, reject) => {
connection.query(thesql, function(err, result) {
if(err){
reject(1)
console.log(err+'err')
}
resolve(0)
})
})
}
var data={
}
var res= await searchSql(updateSql)
if(res==0){
data.msg="更新成功"
data.code=0
ctx.body=data
}else{
data.code=1
data.msg="更新失败,请稍后再试！"
ctx.body=data
}
});
//删除数据
router.post('/remove', async (ctx, next) => {
var deleteSql="DELETE FROM address WHERE "+"id='"+ctx.request.query.id + "'"
var searchSql = (thesql) => {
return new Promise((resolve, reject) => {
connection.query(thesql, function(err, result) {
if(err){
reject(1)
console.log(err+'err')
}
resolve(0)
})
})
}
var data={
}
var res= await searchSql(deleteSql)
if(res==0){
data.msg="删除成功"
data.code=0
ctx.body=data
}else{
data.code=1
data.msg="删除失败,请稍后再试！"
ctx.body=data
}
});
精华部分
- 拼接sql操作语句
- 执行sql操作语句
- 处理结果
增删改查sql语句
增 ：INSERT INTO address (createdTime,name,address,phone,belongsId) VALUES(?,?,?,?,?)
var queryParams=[createdTime,ctx.request.query.name,ctx.request.query.address,ctx.request.query.phone,ctx.request.query.userId]
address 为查询表名称 queryParams为插入的新数据对应上面？的个数 也可直接讲问号替换为对应的值
删：“DELETE FROM address WHERE “+“id=‘11111’’” id=‘11111’ 为删除符合的条件
address 为查询表名称 WHERE 为满足删除的条件
改：“UPDATE address SET name = '”+ctx.request.query.name+”’, phone = ‘" + ctx.request.query.phone + "’, address = ‘" + ctx.request.query.address +"’ where id = ‘" +ctx.request.query.id + "’"
address 为查询表名称 SET 和where之间为插入数据 where后为插入数据的id
查：SELECT * FROM address where belongsId= ‘"+ctx.request.query.userId+"’ limit “+ (ctx.request.query.pageNo-1)*ctx.request.query.pageSize+”," + ctx.request.query.pageSize
pageNo为查询页码 pageSize为查询条数 belongsId=“” 为查询条件 address 为查询表名称
执行sql语句的方法 可统一封装减小代码量
var searchSql = (thesql) => {
return new Promise((resolve, reject) => {
connection.query(thesql, function(err, result) {
if(err){
reject(1) //返回状态
console.log(err+'err')
}
resolve(0) //返回状态 //只有查询有具体返回内容
})
})
}