how to insert a DATE value in sql code example

Example 1: insert date sql

INSERT INTO FOO (xpto) VALUES(TO_DATE('17/12/2015', 'DD/MM/YYYY'));

Example 2: how to add amount between date in sql

mysql> select sum(Value) from DemoTable1444 where PurchaseDate between '2019-10-02' and '2019-12-31';