What is the result of a condition when a subquery returns zero tuples ?

Question

I was reading an article regarding the use of ALL, SOME, ANY operatorshttps://oracle-base.com/articles/misc/all-any-some-comparison-conditions-in-sql . In the ALL section, it was mentioned that "If a subquery returns zero rows, the condition evaluates to TRUE" . In the ANY section, however, it was mentioned that "If a subquery returns zero rows, the condition evaluates to FALSE." . Why are the results of the same subquery different for two operators ? It should evaluate to false for both the cases. What am I missing here ?

Answer 1

ALL ( {} ) = TRUE

ANY ( {} ) = FALSE

This is just the semantic of ALL and ANY. ALL means the condition must be true for ALL tuples and hence this becomes trivially TRUE for {}. ANY means there must exist at least one tuple for which the condition is TRUE and hence this becomes trivially false for {}.