bisher Oracle mit der Zeit
-- TO_TIMESTAMP(date_string,'YYYY-MM-DD HH24:MI:SS')
SELECT TO_TIMESTAMP('2021-02-21 23:12:01','YYYY-MM-DD HH24:MI:SS') FROM DUAL;
VasteMonde
-- TO_TIMESTAMP(date_string,'YYYY-MM-DD HH24:MI:SS')
SELECT TO_TIMESTAMP('2021-02-21 23:12:01','YYYY-MM-DD HH24:MI:SS') FROM DUAL;-- In SESSION time zone
SELECT current_timestamp FROM dual; -- 2021-05-07 05:36:57.476000
SELECT current_timestamp(2) FROM dual; -- 2021-05-07 05:36:57.470000
SELECT current_date FROM dual; -- 2021-05-07 05:36:57
-- In SYSTEM on which database resides
SELECT systimestamp FROM dual; -- 2021-05-07 07:36:57.762000 +02:00
SELECT sysdate FROM dual; -- 2021-05-07 07:36:57SELECT TO_DATE('14/07/2021','DD/MM/YYYY') FROM DUAL;
WATCH OUT!
/* in the example before if you write '14072021' instead of '14/07/2021'
you'll get the same result, if you want an exception to be thrown you
should add the prefix 'fx' (force) to the format, so that he will
match only the exact format. here's some examples:
SELECT TO_DATE('14/07/2021','fxDD/MM/YYYY') FROM DUAL;--WORKS
SELECT TO_DATE('14072021','DD/MM/YYYY') FROM DUAL; --WORKS
SELECT TO_DATE('14072021','fxDD/MM/YYYY') FROM DUAL;--EXCEPTION */SELECT FIRST_NAME FROM EMPLOYEES WHERE HIRE_DATE < TO_DATE('2017-01-01', 'yyyy-mm-dd');