Sequence problem plus

Question

Hi, I have some questions regarding sequences and more
In short,
I want to implement a table column that will be an autoincrement int.
This is used as a PK to another table that holds accounting records.
I use a cashed sequence to get autonumbers.
Also I want this column to show always the current value of the sequence (thus the last PK used on the records table), in order to be treated like an updatable column.
I will then implement an update trigger in the table holding the column in order for the sequence to be altered accordingly whenever an update occurs.
So this column is behaving like a pseudocolumn.
Can u please comment on this or give some insight on how this can be done?
Thanks in advance,
teo

Answer 1

If you have to reset the sequence to a specific value, then the easiest way is to drop and recreate the sequence. If you increment/decrement, then the only way is that posted by Gints, that is
ALTER SEQUENCE DSE INCREMENT BY a number
SELECT DSE.NEXTVAL from dual
ALTER SEQUENCE DSE INCREMENT BY 1
If not, the increment will work at next nextval. Example :
SCOTT@orcl SQL> create sequence s1 start with 100;
Sequence created.
SCOTT@orcl SQL> select s1.nextval from dual;
   NEXTVAL
       100
SCOTT@orcl SQL> alter sequence s1 increment by 10;
Sequence altered.
SCOTT@orcl SQL> select s1.nextval from dual;
   NEXTVAL
       110
SCOTT@orcl SQL> select s1.nextval from dual;
   NEXTVAL
       120
SCOTT@orcl SQL>