oracle-序列 ora-02287 此处不允许序号

今天在生产数据库执行时报ora-02287 此处不允许序号
类似：
SELECT distinct
SYS_GUID(),
‘Y’ ACTIVE,
‘N’ IsRedBack,
‘N’ IsInit,
1 VersionNo,
‘YS2’ || LPAD(STL.SQ_YS2.NEXTVAL, 9, ‘0’) ReceivableNo
from dual
经查使用序列是有限制的：
Restrictions on Sequence Values You cannot use CURRVAL and NEXTVAL in the
following constructs:
■ A subquery in a DELETE, SELECT, or UPDATE statement
■ A query of a view or of a materialized view
■ A SELECT statement with the DISTINCT operator
■ A SELECT statement with a GROUP BY clause or ORDER BY clause
■ A SELECT statement that is combined with another SELECT statement with the
UNION, INTERSECT, or MINUS set operator
■ The WHERE clause of a SELECT statement
■ The DEFAULT value of a column in a CREATE TABLE or ALTER TABLE statement
■ The condition of a CHECK constrain
所以我这里是犯了A SELECT statement with the DISTINCT operator，
修改为：
select SYS_GUID(),
‘YS2’ || LPAD(STL.SQ_YS2.NEXTVAL, 9, ‘0’) ReceivableNo,
T.*
FROM (
SELECT distinct
‘Y’ ACTIVE,
‘N’ IsRedBack,
‘N’ IsInit,
1 VersionNo
from dual
)T
这样就可以避免 A query of a view or of a materialized view
和
A SELECT statement with the DISTINCT operator