select * from data where sn='ds0' order by id desc limit 4
idsntspqvaluesystemts
20702655 ds0 temp 16.30 1558463364 Tue 21 05 2019 20:29:24
20702654 ds0 hum 69.80 1558463364 Tue 21 05 2019 20:29:24
20702647 ds0 hum 69.80 1558463343 Tue 21 05 2019 20:29:03
20702646 ds0 temp 16.30 1558463343 Tue 21 05 2019 20:29:03

Tue May 21 20:29:37 2019 by walley