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select CAST(SUM((year * 365 + month * 31 + day) / 365) AS INT) years ,
CAST(MOD(SUM(month * 31 + day)/31, 12) AS INT) month,
MOD(SUM(day) , 31) day
from
(
Select 1 as year, 5 as month, 10 as day from dual
union all
Select 1 as year, 10 as month, 25 as day from dual
) t1;
| YEARS | MONTH | DAY |
|---|---|---|
| 3 | 4 | 4 |