Try this:
| makeresults
| eval "timestamp"="2019.02.19-10:20:30","label"="xxx","size"="100"
| append
[ makeresults
| eval
"timestamp"="2019.02.19-10:20:30","label"="yyy","size"="250"]
| append
[ makeresults
| eval
"timestamp"="2019.02.19-10:20:30","label"="zzz","size"="300"]
| append
[ makeresults
| eval "timestamp"="2019.02.20-10:20:30","label"="xxx","size"="400"]
| append
[ makeresults
| eval "timestamp"="2019.02.20-10:20:30","label"="yyy","size"="500"]
| append
[ makeresults
| eval
"timestamp"="2019.02.20-10:20:30","label"="zzz","size"="900"]
| fields - _time timestamp
| stats first(size) as size_1 last(size) as size_2 range(size) as diff_size by label
... View more