假如刚刚打开一个会话 ,例如用PL/SQL developer打开一个command窗口 执行一个 SQL> create sequence seq_test_id start with 1;Sequence createdSQL> select seq_test_id.currval from dual; select seq_test_id.currval from dualORA-08002: sequence SEQ_TEST_ID.CURRVAL is not yet defined in this session这时会告诉你 sequence SEQ_TEST_ID.CURRVAL is not yet defined in this session 显然SEQ_TEST_ID当前是存在的，而其sequence对象应该也和session无关. 如何解决这个问题 呢 ？？ 只需要执行 SQL> select seq_test_id.nextval from dual; NEXTVAL ---------- 1SQL> select seq_test_id.currval from dual; CURRVAL ---------- 1原来在查看sequence对象的currval值的时候，必须先要调用它的nextval，实在是没道理的很把，可Oracle就是如此？？ oracle乐于无故增加学习成本阿 /呵呵 只要新打开一个command的窗口，也就会有类似问题，所以记住这个特性就够啦 oracle的错误码也有官方表达ORA-08002: sequence string.CURRVAL is not yet defined in this session Cause: sequence CURRVAL has been selected before sequence NEXTVAL Action: select NEXTVAL from the sequence before selecting CURRVAL Trackback: http://tb.blog.csdn.net/TrackBack.aspx?PostId=1446746
