select * from data where sn='221' and pq='temp' order by id desc limit 4
idsntspqvaluesystemts
29378585 221 temp 13.00 1576443747 Sun 15 12 2019 22:02:27
29378573 221 temp 13.00 1576443727 Sun 15 12 2019 22:02:07
29378561 221 temp 13.00 1576443707 Sun 15 12 2019 22:01:47
29378556 221 temp 13.00 1576443706 Sun 15 12 2019 22:01:46

Sun Dec 15 22:03:19 2019 by walley