Código SQL [-] SELECT (DATEDIFF(SECOND, CAST(T1 AS TIME), CAST(T2 AS TIME)) / 3600) || ':' || (MOD(DATEDIFF(SECOND, CAST(T1 AS TIME), CAST(T2 AS TIME)), 3600) / 60) || ':' || MOD(DATEDIFF(SECOND, CAST(T1 AS TIME), CAST(T2 AS TIME)), 60) FROM LATABLA
SELECT (DATEDIFF(SECOND, CAST(T1 AS TIME), CAST(T2 AS TIME)) / 3600) || ':' || (MOD(DATEDIFF(SECOND, CAST(T1 AS TIME), CAST(T2 AS TIME)), 3600) / 60) || ':' || MOD(DATEDIFF(SECOND, CAST(T1 AS TIME), CAST(T2 AS TIME)), 60) FROM LATABLA