Why does where crookedly work with boolean?

Question

PostgreSQL

select count(*) from  orders  where is_break  is null or is_break = false //результат 895
select count(*) from  orders  where is_break != true //результат 0

is_break is boolean

Answer 1

Because SQL is ternary logic. true, false and NULL: https://www.postgresql.org/docs/current/functions-...
null != whatever - will be null in the result.

Answer 2

well, if everything is true for you, how else to answer him?