private SqlPredicateFragment
    inStringHelper(String cn, FieldPredicate<?> model, boolean negated) {
        final Set<?> set = getFirstOperandAsRawSet(model);
        if (set.isEmpty()) {
            return negated ? alwaysTrue() : alwaysFalse();
        } else if (set.size() == 1) {
            final Object arg = set.iterator().next();
            return negated
                ? notEqualHelper(cn, String.class, arg)
                : equalHelper(cn, String.class, arg);
        }

        return of("(" + cn + " IN (" +
            set.stream().map(unused -> "?").collect(joining(",")) +
            " COLLATE "+ binaryCollationName +"))", negated
        ).addAll(set);
    }
@author Per Minborg
@author Emil Forslund
runtime-parent/runtime-connector-parent/mysql/src/main/java/com/speedment/runtime/connector/mysql/internal/MySqlSpeedmentPredicateView.java