calculate age from year of birth

There are two ways:

via php

## 2. in php
You can also use php code, as in the following way
(inspired from this page (https://stackoverflow.com/questions/3776682/php-calculate-age), and _slighty modified_: 

    $dob ="$row[anno_nascita]";
    $age = date_diff(date_create($dob), date_create('now'))->y;
    echo "age: $age years
";

via mysql in phpmyadmin

1.do this sql query:
     select *,year(CURDATE())-year(anno_nascita) age from studenti__classi; 
2. save the result as view
3. and so you will have, in the view, the age (of your students, i.g.) that can work in LibreBase (to connect with that view).