Does postgresql know the check condition is valid or not. or can check deduce from multiple conditions - Mailing list pgsql-sql

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postgresql - How to query check the constraint is valid or not - Stack Overflow
Postgres 14 | db<>fiddle (dbfiddle.uk)

CREATE TABLE emp (test_check int check ( test_check >1 and test_check < 0 ));

alter table emp  VALIDATE CONSTRAINT emp_test_check_check;```

select * from pg_constraint where conname = 'emp_test_check_check';

Even with the above mentioned step, does postgresql know above check constraint condition always false.

another similar question:
can postgresql deduce from
CREATE TABLE emp1 (test_check int check ( test_check >1 and test_check > 10 ));

to

CREATE TABLE emp1 (test_check int check ( test_check > 10 ));