public function addSelectionColumn($column, $alias = '', $special = '', $variable = '', $additional = ''): self
        {
            if (!$this->table instanceof Table) {
                throw new \Exception('You must set the from-table before adding selection columns');
            }

            $column = $this->getSelectionColumn($column);
            $alias = ($alias === '') ? str_replace('.', '_', $column) : $alias;

            $this->is_custom_selection = true;
            $this->addSelectionColumnRaw($column, $alias, $special, $variable, $additional);

            return $this;
        }