MySQL BLOB to PDF in nodejs

I have few records with BLOBs im posting one record's screenshot below:

i need to convert it back to pdf and save in a folder. here is what i have tried so far but nothing worked:

simply saving blob to file(failed)

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

const con = mysql.createConnection({
  host: "localhost",
  user: "root",
  password: "SQL1234",
  database: "mydb"
});

con.connect(function(err) {
  if (err) throw err;

  const sql = 'SELECT * FROM documents WHERE idnum = 29347';

  con.query(sql, function (err, result, fields) {
    if (err) throw err;
    const row = result[0];
    const pdf = row.pdf;
    fs.writeFileSync('some.pdf', pdf);

  });

});

then converting it to string base64 and using package base64topdf

const base64 = require('base64topdf');
var bufferBase64 = pdf.toString('base64');
let decodedBase64 = base64.base64Decode(bufferBase64, 'finalpdf.pdf');

another failed attempt:

    let buffer = Buffer.from(row.pdf);
    fs.writeFile('file.pdf', buffer, 'binary', function(err) {
        if(err) {
            console.log(err);
        }else{
            console.log('file saved');
            fs.readFile('test.pdf', (err, data) => {
                res.contentType("application/pdf");
                res.send(data);//
            });
        }
    });

using blob-to-buffer:

const toBuffer = require('blob-to-buffer');
 var blob = b64toBlob(row.pdf, 'application/pdf');

 toBuffer(blob, function (err, buffer) {
   if (err) throw err

   buffer[0] // => 1
   buffer.readUInt8(1) // => 2
   let decodedBase64 = base64.base64Decode(buffer, 'myfile2.pdf');
 });

i know im doing something stupid thats y i have posted a screenshot of the blob so you know what kind of data i have. any help would be appreciated.