select s.*
from (select t.event_info_id,
t.event_title,
'1' as alarmType,
t.ext,
'111111' as alarmSource,
t.receiving_datetime,
'匿名' as alarmPersonName,
t.alarm_phone,
t.event_info,
t.process_node_name,
row_number() over(partition by event_info_id order by instr('3,4,6,7,1', t.process_node_name)) as group_idx
from highway_alarm_case t
where t.event_type_id = 26
and substr(t.receiving_datetime, 0, 10) = '2020-05-26'
order by t.receiving_datetime desc) s
where s.group_idx = 1;