SQL Server Obtain Pairs of records - sql

Question

I am trying to obtain "pairs" of records and I just cant figure out.
Here is what I have:
Id TruckId LocationId MaterialMode
145223 1198 19 43
145224 1199 19 43
145225 1200 19 43
145226 1198 20 43
145227 1199 20 43
145228 1200 20 43
145229 1199 21 46
145230 1198 21 46
145231 1200 21 46
145232 1198 22 46
145233 1199 22 46
145234 1200 22 46
145235 1198 19 43
145236 1199 19 43
145237 1200 19 43
145238 1198 20 43
145239 1199 20 43
145240 1200 20 43
145241 1199 21 46
145242 1198 21 46
145243 1200 21 46
145244 1198 22 46
145245 1199 22 46
145246 1200 22 46
I need to get the following:
Id A Id B
145223 145226
145224 145227
145225 145228
145229 145233
145230 145232
145231 145234
145235 145238
145236 145239
145237 145240
145241 145245
145242 145244
145243 145246
Basically matching a TruckId between 2 locations under the same material mode
I have tried:
SELECT
Id AS IdA,
Lead(Id, 1, NULL) OVER(PARTITION BY TruckId, MaterialMode ORDER BY Date) AS IdB
FROM T
This produces:
Id A Id B
145223 145226
145224 145227
145225 145228
*145226 145235
*145227 145236
*145228 145237
145229 145233
145230 145232
145231 145234
*145232 145242
*145233 145241
*145234 145243
145235 145238
145236 145239
145237 145240
145241 145245
145242 145244
145243 145246
Records with the * I don't want them. If a pair is matched then that record should not be part of "another match"

Answer 1

I believe I understand your problem and below is a solution.
Explanation: I sorted the data rows into start and end points sets like in gap and islands problems and then joined a start id with end id for same material mode and truck.
; with separationSet as
(
select
*,
dense_rank()
over(
partition by materialmode,truckid
order by locationid asc
) as r
from T
)
, scoredSet as
(
select
*,
row_number()
over(
partition by materialmode,truckid,r
order by id
) as r2
from separationSet
)
, startToEndPairs as
(
select
S.id as StartId,
E.id as EndId
from scoredSet S
join scoredSet E
on S.r=1 and E.r=2
and S.r2=E.r2
and S.TruckId=E.TruckId
and S.materialmode=E.materialmode
)
select
*
from starttoEndPairs
order by StartId asc
See working demo