SQL> drop table tab1;
drop table tab1
*
ERROR at line 1:
ORA-00604: error occurred at recursive SQL level 1
ORA-01422: exact fetch returns more than requested number of rows

导致这一故障是因为dual字典表出现异常

正常的dual字典表应该是这样：

SQL> select * from dual;

D
-
X

而当依据dual创建新表时，却发现不同:

SQL> create table my_dual as select * from dual;
Table created.

SQL> select * from my_dual;
D
-
X
Y
Y
Y

下面的sql多执行几次，将dual的多余记录删除，即可恢复正常

SQL> delete from dual where dummy = 'Y' and rownum=1;

－EOF－

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