// Sanity-check: Is there ref level 0? If so, this must be fixed to NULL and `level` must be increased by one
$result = sqlQuery('SELECT `id` FROM `{?_MYSQL_PREFIX?}_refsystem` WHERE `level`=0', __FILE__, __LINE__);
// Sanity-check: Is there ref level 0? If so, this must be fixed to NULL and `level` must be increased by one
$result = sqlQuery('SELECT `id` FROM `{?_MYSQL_PREFIX?}_refsystem` WHERE `level`=0', __FILE__, __LINE__);