Taking a day wise backup of large SQL Table incrementally

fetchSave.js

const pg = require('pg-promise')();
const fs = require('fs');

const db = pg({
    user: "****",
    password: "*****",
    host: "******",
    port: 5432,
    database: "*****",
    ssl: {
        rejectUnauthorized: true,
        ca: fs.readFileSync("./rds.pem").toString(),
    },
});

const numberOfDays = 1000; // for backup in past 3 years
const dayInMilliSecond = 86400000;

async function getRecords(from, to) {
    return await db.query(`SELECT * FROM <table> WHERE <any timestamp indexed column> between '${from}' and '${to}'`);
}

async function fetchAndSave() {
    let to = Date.now();
    let from = to - dayInMilliSecond;

    for (let dayIndex = numberOfDays; dayIndex > 0; dayIndex--) {
        const records = await getRecords(new Date(from).toISOString(), new Date(to).toISOString());
        console.log('Records fetched for the day ' + new Date(from).toISOString() + ' =', records.length);

        const formattedRecords = records.map(record => Object.values(record).toString()).join('\n');
        await fs.promises.appendFile('records.csv', formattedRecords);

        to = from;
        from = to - dayInMilliSecond;
    }
}

fetchAndSave(); //without CSV header