对于sequence--currval的疑问

显示全部楼层 · 2008-1-2 17:35:53

SELECT wweb.ops_commuter_cards_s.currval from dual

*
ERROR at line 1:
ORA-08002: sequence OPS_COMMUTER_CARDS_S.CURRVAL is not yet defined in this
session

SQL> c/curr/next
1* SELECT wweb.ops_commuter_cards_s.nextval from dual
SQL> /
NEXTVAL
----------
132061
为什么currval 不能用啊

千问 · 2008-1-2 17:35:53

先执行NEXTVAL,再执行CURRVAL.

千问 · 2008-1-2 17:35:53

我的sequence都
NEXTVAL
----------
132061
这么大了，还用初始化吗？

千问 · 2008-1-2 17:35:53

只有执行过 select sequence.nextval 才能执行 select sequence.currval ！

千问 · 2008-1-2 17:35:53

SQL> select q_taw_rpt_newtree_practise.currval from dual;
select q_taw_rpt_newtree_practise.currval from dual
*
ERROR 位于第 1 行:
ORA-08002: 序列Q_TAW_RPT_NEWTREE_PRACTISE.CURRVAL 尚未在此进程中定义

SQL>select q_taw_rpt_newtree_practise.nextval from dual;
NEXTVAL
----------
8
SQL> select q_taw_rpt_newtree_practise.currval from dual;
CURRVAL
----------
8
必须先执行nextval再执行currval

千问 · 2008-1-2 17:35:53

LZ 回去看看sequence的机制吧.