Zkuste tento dotaz, možná je to to, co hledáte.
;WITH cte AS
(SELECT dbo.Cable.*,
row_number() over(partition by dbo.Cable.TagNo order by dbo.Cable.CableRevision desc) as rn
FROM dbo.Cable
WHERE dbo.Cable.CableRevision = @CoreRevision
), cte2 AS
(SELECT dbo.Cable.TagNo, dbo.Core.*,
row_number() over(partition by dbo.Core.CoreNo order by dbo.Core.CoreRevision desc) as rn
FROM dbo.Core INNER JOIN dbo.Cable ON dbo.Cable.Id = dbo.Core.CableId
WHERE dbo.Core.CoreRevision <= @CoreRevision
)
SELECT *
FROM cte c FULL JOIN cte2 c2 ON c.TagNo = c2.TagNo
WHERE c.rn = 1 OR c2.rn = 1