要使一个视图可以被修改，那么这个视图不能包含以下任何一项：

• Hierarchical query clauses, such as START WITH or CONNECT BY

• GROUP BY or ORDER BY clauses

• MODEL query

• Set operations, such as UNION, UNION ALL, INTERSECT, MINUS

• Aggregate functions, such as AVG, COUNT, MAX, MIN, SUM, and so on

• Analytical functions, such as CUME_DIST, and so on

• A subquery or a collection expression in the SELECT list

• The DISTINCT operator

• WITH READ ONLY option

• The ROWNUM pseudocolumn