My following query sometimes gives 72 rows and sometimes gives 71 rows as
output. How could it misses one?
SELECT distinct on (st.gid) sv.timing, st.gid, st.area
FROM servers sv
INNER JOIN sites st
ON (st_distance(sv.geom, st.geom)<8.5) where
sv.workmode = 1 AND sv.timing >= timestamp '2018-02-02 00:00:00'
and sv.timing <= timestamp '2018-02-02 23:59:59'