MySQL 8.0

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CREATE TABLE tablename (x INTEGER);
INSERT INTO tablename (x) VALUES (1), (2), (3), (3), (2), (4), (6), (8), (9);
SELECT COALESCE(MAX(CASE WHEN x = rn THEN x END), 1) x
FROM (
  SELECT x, DENSE_RANK() OVER (ORDER BY x) + 1 rn
  FROM tablename
  WHERE x > 1 AND EXISTS (SELECT * FROM tablename WHERE x = 1)
) t

x

4

SELECT COALESCE(MAX(CASE WHEN x = rn THEN x END), 2) x
FROM (
  SELECT x, DENSE_RANK() OVER (ORDER BY x) + 2 rn
  FROM tablename
  WHERE x > 2 AND EXISTS (SELECT * FROM tablename WHERE x = 2) 
) t

x

4

SELECT COALESCE(MAX(CASE WHEN x = rn THEN x END), 3) x
FROM (
  SELECT x, DENSE_RANK() OVER (ORDER BY x) + 3 rn
  FROM tablename
  WHERE x > 3 AND EXISTS (SELECT * FROM tablename WHERE x = 3) 
) t

x

4

SELECT COALESCE(MAX(CASE WHEN x = rn THEN x END), 4) x
FROM (
  SELECT x, DENSE_RANK() OVER (ORDER BY x) + 4 rn
  FROM tablename
  WHERE x > 4 AND EXISTS (SELECT * FROM tablename WHERE x = 4)
) t

x

4

SELECT COALESCE(MAX(CASE WHEN x = rn THEN x END), 5) x
FROM (
  SELECT x, DENSE_RANK() OVER (ORDER BY x) + 5 rn
  FROM tablename
  WHERE x > 5 AND EXISTS (SELECT * FROM tablename WHERE x = 5)
) t

x

5

SELECT COALESCE(MAX(CASE WHEN x = rn THEN x END), 6) x
FROM (
  SELECT x, DENSE_RANK() OVER (ORDER BY x) + 6 rn
  FROM tablename
  WHERE x > 6 AND EXISTS (SELECT * FROM tablename WHERE x = 6)
) t

x

6

SELECT COALESCE(MAX(CASE WHEN x = rn THEN x END), 7) x
FROM (
  SELECT x, DENSE_RANK() OVER (ORDER BY x) + 7 rn
  FROM tablename
  WHERE x > 7 AND EXISTS (SELECT * FROM tablename WHERE x = 7)
) t

x

7

SELECT COALESCE(MAX(CASE WHEN x = rn THEN x END), 8) x
FROM (
  SELECT x, DENSE_RANK() OVER (ORDER BY x) + 8 rn
  FROM tablename
  WHERE x > 8 AND EXISTS (SELECT * FROM tablename WHERE x = 8)
) t

x

9

SELECT COALESCE(MAX(CASE WHEN x = rn THEN x END), 9) x
FROM (
  SELECT x, DENSE_RANK() OVER (ORDER BY x) + 9 rn
  FROM tablename
  WHERE x > 9 AND EXISTS (SELECT * FROM tablename WHERE x = 9)
) t

x

9