Index, broken performance

[rrrlasse]

If the value range of integers is large, performance drops towards 0. Reproduce: In test-tightdb, modify % 1000 to % 10000 or more, in these two places:

    // create random string
    const size_t n = rand() % 1000;// * 10 + rand();
    const string s = number_name(n);

(insertion) and

    for (size_t i = 0; i < 100000; ++i) {
        const size_t n = rand() % 1000;
        const size_t res = table.first.Find(n);

(search)