我有如下表所示的源，目标和KMS列，我需要基于KMS列

Question

I need the output based on KMS. Table data and expected output:

1. if KMS is same and source and Target is same(1st and 2nd record are same logically) then consider it as one record

2. If the KMS is same and source and Target is different consider it as different record(consider the last record it has same KMS as 1st record but it different record)

Answer 1

If we consider consider each record as a pair and then sort and transpose the source and target accordingly, you should be able to pick out what records go together.

with data_from_vijay as(
    select 'Bijapur'    as source, 'Bangalore'  as target, 500 as kms from dual union all
    select 'Bangalore'  as source, 'Bijapur'    as target, 500 as kms from dual union all
    select 'Pune'       as source, 'Bangalore'  as target, 700 as kms from dual union all
    select 'Bangalore'  as source, 'Pune'       as target, 700 as kms from dual union all
    select 'Mangalore'  as source, 'Bangalore'  as target, 400 as kms from dual union all
    select 'Bangalore'  as source, 'Belgaum'    as target, 500 as kms from dual
)
select distinct 
       least(source,    target) as source
      ,greatest(source, target) as target
      ,kms
  from data_from_vijay;

The solution does not work for NULLS.