Sequence Number Error

Question

When I try to use sequence number while creating a materialized view,
I got errors:
create materialized view ruby_keywords
build immediate
as
select keyword, keyword_id_sequence.nextval
from (
select distinct name as keyword
from product
union
select distinct description as keyword
from product
Here is the error info:
SQL Error: ORA-02287: sequence number not allowed here
02287. 00000 - "sequence number not allowed here"
How could I solve the issue here?
The sequence is already created with the following statement:
create sequence keyword_id_sequence
start with 1
nomaxvalue;
Thanks,
J

Answer 1

try creating a function and call the same function in the view.
SQL> select seq_id.nextval from dual;
   NEXTVAL
        43
SQL> create or replace view view_sequence as
  2  select seq_id.nextval from dual;
select seq_id.nextval from dual
ERROR at line 2:
ORA-02287: sequence number not allowed here
SQL> create or replace function fnd_sequence
  2    return number is
  3    vSeqId number := 0;
  4  begin
  5    select seq_id.nextval into vSeqId from dual;
  6    return(vSeqId);
  7  end;
  8  /
Function created.
SQL> select fnd_sequence from dual;
FND_SEQUENCE
          44
SQL> create or replace view view_sequence as
  2   select fnd_sequence from dual;
View created.
SQL> select * from view_sequence;
FND_SEQUENCE
          45
SQL>note: i have only tried the view you may try it on a materialized view to see if it might work