PL SQL Data Types Oracle PLSQL Tutorial

declare
    variable1_int INTERVAL YEAR[(precision)] TO MONTH;
begin
    NULL;
end;
The INTERVAL YEAR TO MONTH datatype allows you to store and manipulate intervals of years and months.
You can specify the number of digits in years that you want to store (by default 2, available range is 0?).
INTERVAL DAY

declare
    variable2_int INTERVAL DAY[(precision)] to SECOND[(precision)];
begin
    NULL;
end;
The INTERVAL DAY TO SECOND datatype allows you to store and manipulate intervals of days, hours, minutes, and seconds.
In this case, day precision allows you to set the number of digits you want to store, and second precision identifies the number of digits used to store fractions of seconds.