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alter session set nls_date_format = 'YYYY-MM-DD HH24:MI:SS'
alter session set nls_timestamp_format = 'YYYY-MM-DD HH24:MI:SS.FF1'
alter session set nls_timestamp_tz_format = 'YYYY-MM-DD HH24:MI:SS.FF1 TZR'
select SYSDATE, SYSTIMESTAMP DBTIMEZONE from dual;
| SYSDATE | DBTIMEZONE |
|---|---|
| 2022-09-06 18:06:04 | 2022-09-06 18:06:04.9 +01:00 |
select SYSTIMESTAMP, SYSTIMESTAMP at time zone 'UTC' from dual;
| SYSTIMESTAMP | SYSTIMESTAMPATTIMEZONE'UTC' |
|---|---|
| 2022-09-06 18:06:04.9 +01:00 | 2022-09-06 17:06:04.9 UTC |
select cast(SYSTIMESTAMP at time zone 'UTC' as date) from dual;
| CAST(SYSTIMESTAMPATTIMEZONE'UTC'ASDATE) |
|---|
| 2022-09-06 17:06:04 |
-- original
select round((SYSDATE - date '1970-01-01')*24*60*60) from dual;
| ROUND((SYSDATE-DATE'1970-01-01')*24*60*60) |
|---|
| 1662487564 |
select round((cast(SYSTIMESTAMP at time zone 'UTC' as date) - date '1970-01-01')*24*60*60) from dual;
| ROUND((CAST(SYSTIMESTAMPATTIMEZONE'UTC'ASDATE)-DATE'1970-01-01')*24*60*60) |
|---|
| 1662483964 |