vector<Column*> _columns;
Column* value;
char* name;

Table(char* name) {...}

~Table() {...}

template <typename T>
void addColumn(vector<T> v) {
    auto column = DataColumnFactory::getColumn();
    column.get()->addValuesToVector(v);
    _columns.push_back(move(column));
}


int findLongestColumn() {
    int length = 0;
    for (auto &column : _columns) {
        if (length < column.get()->lengthOfColumn()) //ERROR
            length = column.get()->lengthOfColumn();
    }
}