Improve dictionary access from AbstractTable

[mrks]

I believe that this (in AbstractTable::setValue) can be improved, as the current implementation requires two tree traversals whenever a value is inserted:

if (map->valueExists(value)) {
      valueId.valueId = map->getValueIdForValue(value);
    } else {
      valueId.valueId = map->addValue(value);
    }
}

If we added a map::insert-like interface to the BaseDictionary, we could do this in one step:

The single element versions (1) return a pair, with its member pair::first set to an iterator pointing to either the newly inserted element or to the element with an equivalent key in the map.

[bastih]

👍

[grundprinzip]

+1