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Como obter o valor da linha anterior e atual usando o CTE recursivo?


Isso pressupõe valores crescentes de ID e lidará com lacunas no ID
SELECT
   ID, 
   This.Number AS CurrentValue, 
   Prev2.Number AS PreviousValue
FROM
   myTable This
   OUTER APPLY
   (
    SELECT TOP 1
       Number
    FROM
       myTable Prev
    WHERE
       Prev.ID < This.ID  -- change to number if you want
    ORDER BY
       Prev.ID DESC
   ) Prev2;

OU
WITH CTE
     AS (SELECT ID,
                Number,
                ROW_NUMBER() OVER (ORDER BY ID) AS rn
         FROM   Mytable)
SELECT ID,
       This.Number AS CurrentValue,
       Prev.Number AS PreviousValue
FROM   CTE This
       LEFT JOIN CTE Prev
         ON Prev.rn + 1 = This.rn; 

E para o SQL Server 2012
SELECT
   ID,
   Number AS CurrentValue,
   LAG(Number) OVER (ORDER BY ID) AS PreviousValue
FROM
   MyTable