How to securely load data from a database using AJAX?

Question

PHP

How to securely load data from a database using AJAX?

Answer 1

JSON

Answer 2

Your front should use ajax to interact with the PHP/Python backend or something else, exchanging data in json format. And the backend, in turn, must interact with the base. That is, the question is formulated not quite correctly.
As for security, there must be a normal password to connect to the database, the user is not root, and it is also desirable that there is a list of allowed IPs to connect to the database, so that anyone from anywhere could not get into the database.

Answer 3

Render turned off the music
"A complete description of the system ... will take at least six solid volumes - in German," he decided.