**Describe the bug**
`SELECT i FROM generateRandom('i Array(Int8)', 1048575, 10, 1048577) LIMIT 1048575`

Memory limit should be respected.
{
    if (relative_path.empty())
        throw Exception("Part relative_path cannot be empty. It's bug.", ErrorCodes::LOGICAL_ERROR);
    return storage.getFullPathOnDisk(volume->getDisk()) + relative_path + "/";
}
String IMergeTreeDataPart::getFullRelativePath() const