Error ORA-02287
SQL> create sequence pepito;
Sequence created
SQL> select pepito.nextval from dual union all select pepito.nextval from dual;
select pepito.nextval from dual union all select pepito.nextval from dual
ORA-02287: número de secuencia no permitido aquí
SQL> select pepito.nextval from dual ;
NEXTVAL
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1
In release 11 and 12.1.0.2