SELECT GREATEST(column_1) AS gr FROM ...

DELIMITER $$
CREATE DEFINER=`root`@`localhost` FUNCTION `JSON_BUBBLE_SORT`(`JsonArray` JSON) RETURNS json
    NO SQL
BEGIN

DECLARE ArrayCount INT DEFAULT JSON_LENGTH(JsonArray);
DECLARE i, x INT DEFAULT 0;
DECLARE CurrElTmpl, NextElTmpl VARCHAR(6);
DECLARE CurrElVal, NextElVal INT;

WHILE i < ArrayCount DO
   
  WHILE x < ArrayCount - 1 DO
  
  SET CurrElTmpl = CONCAT_WS(x, '$[', ']');
  SET NextElTmpl = CONCAT_WS(x + 1, '$[', ']');
  
  SET CurrElVal = JSON_EXTRACT(JsonArray, CurrElTmpl);
  SET NextElVal = JSON_EXTRACT(JsonArray, NextElTmpl);

  SET JsonArray = IF (CurrElVal > NextElVal,
        JSON_REPLACE(JsonArray, CurrElTmpl, NextElVal, NextElTmpl, CurrElVal),
        JsonArray);

  SET x = x + 1;
  END WHILE;

SET x = 0;
SET i = i + 1;
END WHILE;

  RETURN JsonArray;
END$$
DELIMITER ;

SET @Params = (SELECT column_1 FROM `table_1` WHERE `id` = '1');
SET @Sorted = JSON_BUBBLE_SORT (@Params);

SET @Min = JSON_EXTRACT(@Sorted, '$[0]');
SET @Max = JSON_EXTRACT(@Sorted, '$[last]');

SELECT @Min, @Max;