How to add a field into the system config programatically? (duplicate)

dmitrii_fediuk · April 8, 2016, 2:16pm

It should work for new fields too.
Just see its implementation:

magento/magento2/blob/2.0.0/app/code/Magento/Config/Model/ResourceModel/Config.php#L54-L59


if ($row) {
    $whereCondition = [$this->getIdFieldName() . '=?' => $row[$this->getIdFieldName()]];
    $connection->update($this->getMainTable(), $newData, $whereCondition);
} else {
    $connection->insert($this->getMainTable(), $newData);
}