Equality conditions are
search conditions with a comparison predicate, to which the following rules apply:Only equality conditions that satisfy these prerequisites can use the Optimizer to determine an optimal
search strategy.Conditions in the format
...NOT (<column_spec> <> <extended_value_spec>) or ...NOT (<column_spec> <> <subquery>) are, where possible, converted into an expression without NOT, with a correspondingly negated operator =. The system then continues processing the condition in this converted format.