Difference between two access tables

By a query maybe?
You create a query from table 2, in creation mode you insert table 1, and display the fields, you establish the links from the elements of table 2 to table 1 by choosing, "property: include all records from table 2 and only those from table 1 where the links are equal."
When you run the query, you will see that all elements of table 2 appear along with those from table 1 that are relevant, while the others remain empty. Just enter "null" in the "criteria" of the query for the concerned column of table 1 and you will get the rows of table 1 that do not exist in table 2.
Not easy to explain like this, I wouldn't manage it in SQL mode, but if there's an easier way, go ahead guys, let loose!