oracle 此处不允许序列

樊8291

　　一个插入语句，这样写报错：此处不允许序列
　　insert into t_dict_product_mapping(f_dict_id, f_product_code_jifei, f_product_name_jifei)
　　select s_dict_product_mapping.nextval dictid,gid,gname from t_dw_fltelecomproduct_all a
　　group by gid,gname
　　
　　改写成这样既可继续
　　insert into t_dict_product_mapping(f_dict_id, f_product_code_jifei, f_product_name_jifei)
　　select s_dict_product_mapping.nextval dictid,gid,gname from (
　　select gid,gname from t_dw_fltelecomproduct_all a
　　group by gid,gname
　　)
　　
　　报错原因，group by语句中不能是会用序列，详见帮助文档
　　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    --这个就是我遇到的那种情况
　　■ 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