Jarves\Admin\FieldTypes\AbstractSingleColumnType::getColumns PHP Method

    public function getColumns()
    {
        $columnDefinition = new ColumnDefinition();
        $columnDefinition->setPhpDataType($this->getPhpDataType());
        $type = $this->getSqlDataType();
        if ($maxLength = $this->getFieldDefinition()->getMaxLength()) {
            $type .= '(' . $maxLength . ')';
        }
        $columnDefinition->setSqlDataType($type);
        $columnDefinition->setName($this->getFieldDefinition()->getId());
        if ($regex = $this->getFieldDefinition()->getRequiredRegex()) {
            $columnDefinition->setRequiredRegex($regex);
        }
        return [$columnDefinition];
    }