Why is the data not being assigned to a variable?

Question

Node.js

Good afternoon, to be honest, I don’t understand at all why my data is not assigned ... The data is displayed in the console log, but not in the variable, why is that?

let data

connection.query(`SELECT * FROM items`, function (err, results) {
    if (err) console.log(err)
    data = results
})

connection.end();

console.log(data)

Answer 1

if (err) console.log(err)
This console log should contain an error and not data