DDL则可以正常执行：

SQL> SELECT * FROM T;

ID
----------
1
2
3

SQL> SELECT * FROM T FOR UPDATE;
SELECT * FROM T FOR UPDATE
*
ERROR at line 1:
ORA-12081: update operation not allowed on table "YANGTK"."T"

SQL> ALTER TABLE T ADD NAME VARCHAR2(30);
ALTER TABLE T ADD NAME VARCHAR2(30)
*
ERROR at line 1:
ORA-12081: update operation not allowed on table "YANGTK"."T"

SQL> ALTER TABLE T MODIFY ID NOT NULL;
ALTER TABLE T MODIFY ID NOT NULL
*
ERROR at line 1:
ORA-12081: update operation not allowed on table "YANGTK"."T"

SQL> ALTER TABLE T ALLOCATE EXTENT;

Table altered.

SQL> ALTER TABLE T CACHE;

Table altered.