SQL Server 2016

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CREATE TABLE #A (UpperLimit NUMERIC(4));
CREATE TABLE #B (Id NUMERIC(4), Amount NUMERIC(4));

INSERT INTO #A VALUES 
    (1000), (2000), (3000);
INSERT INTO #B VALUES 
    (1, 3100), 
    (2, 1900), 
    (3, 1800), 
    (4, 1700), 
    (5, 900), 
    (6, 800);

WITH 
DATA AS
(
  SELECT * 
  FROM #A A1
    INNER JOIN #B B1 ON A1.UpperLimit >= B1.Amount
),
MA AS
(
  SELECT MIN(UpperLimit) AS MinLimit, MAX(UpperLimit) AS MaxLimit
  FROM #A
),
RESULT AS 
(
  SELECT * 
  FROM DATA D1
  WHERE NOT EXISTS 
        (SELECT 1 
        FROM DATA D2 
        WHERE D2.UpperLimit = D1.UpperLimit AND D2.Amount > D1.Amount)
        AND D1.UpperLimit = (SELECT MaxLimit FROM MA)
  UNION ALL      
  SELECT D1.* 
  FROM RESULT R1 INNER JOIN DATA D1 
       ON (R1.UpperLimit > D1.UpperLimit AND R1.Id != D1.Id) 
  WHERE D1.UpperLimit >= (SELECT MinLimit FROM MA)
       AND NOT EXISTS 
        (SELECT 1 
        FROM DATA D2 
        WHERE D2.UpperLimit = D1.UpperLimit AND D2.Amount > D1.Amount AND D2.Id != R1.Id)   
)

SELECT DISTINCT * FROM RESULT ORDER BY UpperLimit DESC;

UpperLimit	Id	Amount
3000	2	1900
2000	3	1800
1000	5	900