SQL Server 2016

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CREATE TABLE DST
( 
ID varchar(255),
ROUTE varchar(255),
LNO varchar(255)
);

INSERT INTO DST(ID,ROUTE, LNO)

SELECT '1' ID, 'JFK-LAX' ROUTE, '1' LNO UNION ALL
SELECT '1' ID, 'LAX_IAD' ROUTE, '2' LNO UNION ALL
SELECT '1' ID, 'IAD-ORD' ROUTE, '3' LNO UNION ALL
SELECT '5' ID, 'MIA-ATL' ROUTE, '1' LNO UNION ALL
SELECT '5' ID, 'ATL-MIA' ROUTE, '2' LNO UNION ALL
SELECT '2' ID, 'SEA-IAH' ROUTE, '1' LNO UNION ALL
SELECT '2' ID, 'IAH-AUS' ROUTE, '2' LNO UNION ALL
SELECT '2' ID, 'AUS-SEA' ROUTE, '3' LNO
8 rows affected

SELECT ID, (
    SELECT case when LNO = 1 then ROUTE else right(ROUTE, 4) end
    FROM DST d2
    WHERE ID = d.ID
    ORDER BY LNO
    FOR XML PATH(''), TYPE).value('.', 'VARCHAR(MAX)') AS Route
FROM DST d
GROUP BY ID;


ID
Route


1
JFK-LAX_IAD-ORD

2
SEA-IAH-AUS-SEA

5
MIA-ATL-MIA


with dataX as (
SELECT ID, STUFF((
    SELECT '-' + ROUTE
    FROM DST
    WHERE ID = d.ID
    ORDER BY LNO
    FOR XML PATH(''), TYPE).value('.', 'VARCHAR(MAX)'), 1, 1, '') AS Route
FROM DST d
GROUP BY ID
)
select Route7
from dataX cross apply (values(coalesce(stuff(Route,   9, 4, ''), Route ))) v2(Route2)
           cross apply (values(coalesce(stuff(Route2, 13, 4, ''), Route2))) v3(Route3)
           cross apply (values(coalesce(stuff(Route3, 17, 4, ''), Route3))) v4(Route4)
           cross apply (values(coalesce(stuff(Route4, 21, 4, ''), Route4))) v5(Route5)
           cross apply (values(coalesce(stuff(Route5, 25, 4, ''), Route5))) v6(Route6)
           cross apply (values(coalesce(stuff(Route6, 31, 4, ''), Route6))) v7(Route7)


Route7


JFK-LAX-IAD-ORD

SEA-IAH-AUS-SEA

MIA-ATL-MIA


with dataX as (
SELECT ID, STUFF((
    SELECT '-' + ROUTE
    FROM DST
    WHERE ID = d.ID
    ORDER BY LNO
    FOR XML PATH(''), TYPE).value('.', 'VARCHAR(MAX)'), 1, 1, '') AS Route
FROM DST d
GROUP BY ID
)
select Route7
from dataX cross apply (values(stuff(Route + replicate(' ', 100), 9, 4, ''))) v2(Route2)
           cross apply (values(stuff(Route2, 13, 4, ''))) v3(Route3)
           cross apply (values(stuff(Route3, 17, 4, ''))) v4(Route4)
           cross apply (values(stuff(Route4, 21, 4, ''))) v5(Route5)
           cross apply (values(stuff(Route5, 25, 4, ''))) v6(Route6)
           cross apply (values(rtrim(stuff(Route6, 31, 4, '')))) v7(Route7)


Route7


JFK-LAX-IAD-ORD

SEA-IAH-AUS-SEA

MIA-ATL-MIA