Develop Reference

How to send multiple query results from backend to frontend in node

I am making a simple check-in and check-out system for employees. In the main panel I want to show the number of hours worked per day and in another field the weekly total.
I can now show the hours per day in a table, the problem comes when I have to show the total since I make that query to the database with another query.
With the following code I perform the query and perform a render in the index view using the EJS templates.:
router.get('/', (req, res) => {
const week = DateTime.now().weekNumber;
conexion.query('SELECT * FROM assistance WHERE week = ?', week, (error, results) => {
if(error){
throw error;
}else{
res.render('index', {results: results});
}
})
});
With this code I perform the query of the total hours. but I don't know how to show it in the same index view since it is a separate query from the first one:
conexion.query('SELECT time_format(SUM(TIMEDIFF(a.exit, a.entry)), "%H:%i") AS hours from assistance a WHERE a.week = ?', week, (error, results) => {
if(error){
throw error;
}else{
return('index', {totalHours: results});
}
})
In this way I am trying to receive the information in the index view with EJS:
<div>
<div>Total hours:<%= totalHours%></div>
</div>

Use try/catch async-await, then just do both queries.
router.get('/', async(req, res) => {
const week = DateTime.now().weekNumber
try {
// query 1
const totalHours = await conexion.query('SELECT time_format(SUM(TIMEDIFF(a.exit, a.entry)), "%H:%i") AS hours from assistance a WHERE a.week = ?', week)
// query 2
const results = await conexion.query('SELECT * FROM assistance WHERE week = ?', week)
res.render('index', {
totalHours,
results
})
} catch {
res.render('error-page')
}
})

How to implement promises in nodejs?

I made this project based on a YT tutorial but adding some extra features
image
the problem I have is the following, this is the code that is used to show the data of the database
controller.list = (req, res) => {
req.getConnection((err, conn) => {
conn.query("SELECT * FROM usuarios ", (err, usuarios) => {
if(err){
res.json(err)
}
res.render("usuarios", {
data: usuarios
})
})
})
}
but I don't know how to modify it so that in the part that says "usado" it shows me the number of times that the "Codigo" is repeated. I know that with a MySQL query similar to this one 'SELECT COUNT(*) AS namesCount FROM names WHERE age = ?' I can show the number of times it repeats, but I don't know how to implement this in the controller, I know I can do it with promises but I don't know how to modify the code to implement it.

How do I get all objects with a specific start date

I'm trying to use a date parameter that comes in through the request and return all objects that have that date. I do not want to look at the time stamp, just the year, month, day.

The following in the controller file of mongoose finds dates that match a specific day:
export const getBookingByDate = (req, res) => {
Booking.find({start: {$gt: req.params.bookingDate}}, (err, booking) => {
if(err){
res.send(err);
}
res.json(booking);
})
}

NodeJs insert current Datetime field into MySQL db

I'm trying to insert a DATETIME field into my MySQL db.
var dt = require('moment')().format('YYYY-MM-DD HH:mm:ss');
pool.query(
`insert into login(id, id_utente, data_login) values(NULL,?,?)`,
[results[0].id],
[dt],
(error, results, fields) => {
}
);
I get this error:
C:\Users\tiger\Desktop\prova\REST_API_WITH_MYSQL-master\node_modules\mysql\lib\protocol\Parser.js:437
throw err; // Rethrow non-MySQL errors
^TypeError: this._callback.apply is not a function
If I try this code, everything comes right:
pool.query(
`insert into login(id, id_utente, data_login) values(NULL,?,"2021-01-27 00:00:00")`,
[results[0].id],
//[dt],
(error, results, fields) => {
}
);
What i'm doing wrong?

You have your parameters in 2 separate arrays. Put your parameters in the same parameter array.
pool.query(
`insert into login(id, id_utente, data_login) values(NULL,?,?)`,
[results[0].id, dt],
(error, results, fields) => {
}
);

The correct format probably is YYYY-MM-DD HH:MM:SS(I think it depends on MySQL configuration, but this is the default) as the docs points out.
So you should try using moment's format() method like this:
const myDate = moment(data.myTime.format('YYYY/MM/DD HH:mm:ss')).format("YYYY-MM-DD HH:mm:ss");
pool.query(
`insert into login(id, id_utente, data_login) values(NULL,?,?)`,
[results[0].id, myDate],
(error, results, fields) => {
}
);

pass a json result of a mysql query as a param to my ejs in Node/express

I have a query to get all my users. I have been doing res.json(rows) to display to screen until now. Now I want to pass the object obtain from the query to a ejs file and display it. If I do like my code below, the object pass is a string and I can´t iterate or obtain the fields.
What is the best way to achive what I´m trying to do?
router.get("/users", (req, res) => {
const connection = getConnection();
const newLocal = "SELECT * FROM client";
connection.query(newLocal,(err, rows, fields) => {
if (err) {
console.log("Error "+err);
res.sendStatus(500);
return;
}
// res.json(rows);
res.render("users.ejs", {users: JSON.stringify(rows)});
});
});

It's because you're turning your Array rows into a String. Remove JSON.stringify