MariaDB 10.6

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select version();

version()

10.6.9-MariaDB-1:10.6.9+maria~deb11

DROP FUNCTION IF EXISTS TOS_GET_DURATION;
CREATE FUNCTION TOS_GET_DURATION(seconds INT) 
  RETURNS VARCHAR(16)
  RETURN CONCAT(LPAD(FLOOR(HOUR(SEC_TO_TIME(seconds)) / 24), 2, 0), ' days ',TIME_FORMAT(SEC_TO_TIME(seconds % (24 * 3600)), '%H:%i:%s'));
SELECT TOS_GET_DURATION(860000);

TOS_GET_DURATION(860000)

09 days 22:53:20