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我有一张road_events桌子:

create table road_events (
    event_id number(4,0),
    road_id number(4,0),
    year number(4,0),
    from_meas number(10,2),
    to_meas number(10,2),
    total_road_length number(10,2)
    );

insert into road_events (event_id, road_id, year, from_meas, to_meas, total_road_length) values (1,1,2020,25,50,100);
insert into road_events (event_id, road_id, year, from_meas, to_meas, total_road_length) values (2,1,2000,25,50,100);
insert into road_events (event_id, road_id, year, from_meas, to_meas, total_road_length) values (3,1,1980,0,25,100);
insert into road_events (event_id, road_id, year, from_meas, to_meas, total_road_length) values (4,1,1960,75,100,100);
insert into road_events (event_id, road_id, year, from_meas, to_meas, total_road_length) values (5,1,1940,1,100,100);

insert into road_events (event_id, road_id, …