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select (timestamp '1970-01-01 00:00:00.0 UTC' + (1539961967567/1000 * interval '1' second))
at time zone 'America/Denver' as denver_time
from dual
| DENVER_TIME |
|---|
| 19-OCT-18 09.12.47.567000000 AM AMERICA/DENVER |
select timestamp '2018-10-19 09:12:47.567 AMERICA/DENVER'
- timestamp '1970-01-01 00:00:00.0 UTC' as diff
from dual;
| DIFF |
|---|
| +000017823 15:12:47.567000000 |
select extract(day from diff) * 86400000
+ extract(hour from diff) * 3600000
+ extract(minute from diff) * 60000
+ extract(second from diff) * 1000 as unixtime
from (
select timestamp '2018-10-19 09:12:47.567 AMERICA/DENVER'
- timestamp '1970-01-01 00:00:00.0 UTC' as diff
from dual
);
| UNIXTIME |
|---|
| 1539961967567 |