code: private Optional<IndexBooleanExpression> getSupplementaryCondition(Set<String> allColumnsInColumnRelations, Map<String, Set<Object>> condition) {
          Map<String, Set<Object>> fixedValuesMap = condition.keySet().stream()
                  .filter(cn -> !allColumnsInColumnRelations.contains(cn))
                  .collect(Collectors.toMap(Function.identity(), condition::get));
          return fixedValuesMap.isEmpty() ?
                  Optional.empty() :
                  Optional.of(new IndexBooleanExpression(fixedValuesMap));
      }
docs: E.g. (a.id = b.id and a.id = '2') and a.name = 'test' <- the last one is supplementary condition