公交查詢系統(tǒng)—數(shù)據(jù)庫課程設(shè)計報告-文庫吧資料
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【正文】 ct id2 = id from station where name = input2 查找直達(dá)線路 select output1 = from (select bus_name from bus_station where station_id = id1 ) a, (select bus_name from bus_station where station_id = id2 ) b where = 若不存在直達(dá)線路,則搜尋一次換乘路線 if not exists(select * from bus where name = output1) begin 查找中間站點 select stationID1 = from input1能直達(dá)的站點集合c ( select distinct station_id from bus_station where bus_name in(select bus_name from bus_station where station_id = id1 )) c, input2能直達(dá)的站點集合d ( select distinct station_id from bus_station where bus_name in(select bus_name from bus_station where station_id = id2)) d where = select output1 = from (select bus_name from bus_station where station_id = id1 ) a, (select bus_name from bus_station where = stationID1 ) b where = select output2 = from (select bus_name from bus_station where station_id = id2) a,(select bus_name from bus_station where = stationID1 ) b where = end 若不存在直達(dá)和一次換乘線路,則搜尋二次換乘路線 if not exists(select * from bus where name = output1) and not exists(select * from bus where name = output2) begin 查找中間線路 select output2 = from (select distinct bus_name from bus_station where station_id in(select station_id from bus_station where bus_name in(select bus_name from bus_station where station_id = id1)))a, (select distinct bus_name from bus_station where station_id in (select station_id from bus_station where bus_name in(select bus_name from bus_station where station_id = id2)))b where = 查找起點到中間線路的公交車 select stationID1 = from (select distinct station_id from bus_station where bus_name in(select bus_name from bus_station where station_id = id1))a, (select station_id from bus_station where bus_name = output2) b where = select output1 = from (select bus_name from bus_station where station_id = id1 ) c, (select bus_name from bus_station where station_id = stationID1) d where = 查找中間線路到終點的公交車 select stationID2 = from (select distinct station_id from bus_station where bus_name in(select bus_name from bus_station where station_id = id2))a, (select station_id from bus_station where bus_name = output2) b where = select output3 = from (select bus_name from bus_station where station_id = id2 ) c, (select bus_name from bus_station where station_id = stationID2) d where = end select output4 = name from station where id = stationID1 select output5 = name from station where id = stationID2end 五、軟件功能設(shè)計軟
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