我需要用nodejs连接微信小程序和本地mysql数据库，要实现以下查询语句： SELECT COUNT(rk) FROM `user_status` where rk ='1' ; SELECT COUNT(ncre) FROM `user_status` where ncre ='1'; SELECT COUNT(cet) FROM `user_status` where cet ='1' ; SELECT COUNT(pth) FROM `user_status` where pth ='1' ; SELECT COUNT(jz) FROM `user_status` where jz ='1' ; 并将查询结果都返回到微信小程序，要如何实现？请写出接口，代码写注释

首先，你需要先在nodejs中连接mysql数据库并编写对应的查询语句。你可以使用mysql模块来进行数据库连接和查询操作。以下是一个简单的示例代码：

const mysql = require('mysql');

// 创建数据库连接
const connection = mysql.createConnection({
  host: 'localhost',
  user: 'root',
  password: 'password',
  database: 'your_database_name'
});

// 连接数据库
connection.connect();

// 查询语句
const query1 = "SELECT COUNT(rk) as rk_count FROM `user_status` where rk ='1' ";
const query2 = "SELECT COUNT(ncre) as ncre_count FROM `user_status` where ncre ='1'";
const query3 = "SELECT COUNT(cet) as cet_count FROM `user_status` where cet ='1' ";
const query4 = "SELECT COUNT(pth) as pth_count FROM `user_status` where pth ='1' ";
const query5 = "SELECT COUNT(jz) as jz_count FROM `user_status` where jz ='1' ";

// 执行查询语句
connection.query(query1 + ";" + query2 + ";" + query3 + ";" + query4 + ";" + query5, (error, results, fields) => {
  if (error) throw error;

  // 查询结果
  const rk_count = results[0][0].rk_count;
  const ncre_count = results[1][0].ncre_count;
  const cet_count = results[2][0].cet_count;
  const pth_count = results[3][0].pth_count;
  const jz_count = results[4][0].jz_count;

  // 返回结果给微信小程序
  res.json({
    rk_count,
    ncre_count,
    cet_count,
    pth_count,
    jz_count
  });
});

// 关闭数据库连接
connection.end();

以上代码中使用了mysql模块来创建数据库连接和执行查询语句。在查询语句中，使用了COUNT函数来统计符合条件的记录数，同时使用了as关键字来为查询结果指定别名，以便在查询结果中获取数据。

接下来，你需要编写一个接口，该接口用于将查询结果返回给微信小程序。以下是一个简单的示例接口代码：

const express = require('express');
const mysql = require('mysql');

const app = express();

// 创建数据库连接
const connection = mysql.createConnection({
  host: 'localhost',
  user: 'root',
  password: 'password',
  database: 'your_database_name'
});

// 连接数据库
connection.connect();

// 查询语句
const query1 = "SELECT COUNT(rk) as rk_count FROM `user_status` where rk ='1' ";
const query2 = "SELECT COUNT(ncre) as ncre_count FROM `user_status` where ncre ='1'";
const query3 = "SELECT COUNT(cet) as cet_count FROM `user_status` where cet ='1' ";
const query4 = "SELECT COUNT(pth) as pth_count FROM `user_status` where pth ='1' ";
const query5 = "SELECT COUNT(jz) as jz_count FROM `user_status` where jz ='1' ";

app.get('/stats', (req, res) => {
  // 执行查询语句
  connection.query(query1 + ";" + query2 + ";" + query3 + ";" + query4 + ";" + query5, (error, results, fields) => {
    if (error) throw error;

    // 查询结果
    const rk_count = results[0][0].rk_count;
    const ncre_count = results[1][0].ncre_count;
    const cet_count = results[2][0].cet_count;
    const pth_count = results[3][0].pth_count;
    const jz_count = results[4][0].jz_count;

    // 返回结果给微信小程序
    res.json({
      rk_count,
      ncre_count,
      cet_count,
      pth_count,
      jz_count
    });
  });
});

// 启动服务器
app.listen(3000, () => {
  console.log('Server started on port 3000');
});

// 关闭数据库连接
connection.end();

以上代码中，我们使用express模块创建了一个简单的HTTP服务器，并创建了一个路由'/stats'，该路由用于返回查询结果。在该路由中，我们执行了查询语句，并将查询结果作为JSON格式返回给微信小程序。