oracle 时间和SCN相互转化

主要使用的是函数 timestamp_to_scn() 和 scn_to_timestamp();

1. 时间转化为SCN

    SQL> select timestamp_to_scn(sysdate) from dual;    SQL> select sysdate from dual;    SYSDATE    ---------    11-MAR-15    SQL> select timestamp_to_scn(sysdate) from dual;    TIMESTAMP_TO_SCN(SYSDATE)    -------------------------              1041879

2. SCN转换为时间

    SQL> select current_scn from v$database;    CURRENT_SCN    -----------        1041902    SQL> select scn_to_timestamp(current_scn) from v$database;    SCN_TO_TIMESTAMP(CURRENT_SCN)    ---------------------------------------------------------------------------    11-MAR-15 02.14.34.000000000 AM