环境：OEL+Oracle 11.2.0.3+physical standby
问题描述：查询dba_temp_files试图时显示Ora-01187错误号；
ORA-01187: cannot read from file because it failed verification tests
ORA-01110: data file 201: '/oradata/seven/temp01.dbf'
重现下错误：
SQL> select file_id,file_name,tablespace_name from dba_temp_files;
select file_id,file_name,tablespace_name from dba_temp_files
*
ERROR at line 1:
ORA-01187: cannot read from file because it failed verification tests
ORA-01110: data file 201: '/oradata/seven/temp01.dbf'
oerr ora解决方法是：
[oracle@Seven trace]$ oerr ora 01187
01187, 00000, "cannot read from file %s because it failed verification tests"
// *Cause: The data file did not pass the checks to insure it is part of the
// database. Reads are not allowed until it is verified.
// *Action: Make the correct file available to the database. Then, either open
// the database, or execute ALTER SYSTEM CHECK DATAFILES.
初步推断是上次DG进行switchover时导致临时数据库文件出错，解决方法是重建临时数据文件；
带着这个疑问google了下，发现好多朋友遇到这个问题，表示重建下临时文件，或者重新reuse下临时表空间都可以处理这个问题，但是对于问题的根本起因，倒是没有找到原因；很遗憾！
还是来说明我自己的处理方法吧：
由于这个DG环境下的primary主库上报的错，对比了一下主备库的temp表空间，都是30M的大小，而且也都是online状态。
SQL> select name,bytes/1024/1024,status from v$tempfile;
NAME BYTES/1024/1024 STATUS
------------------------------ --------------- -------
/oradata/seven/temp01.dbf 30 ONLINE
删除临时文件：
SQL> alter database tempfile '/oradata/seven/temp01.dbf' drop;
Database altered.
SQL> select name,bytes/1024/1024,status from v$tempfile;
no rows selected
重新添加临时数据文件：
SQL> alter tablespace temp add tempfile '/oradata/seven/temp01.dbf' size 30M reuse;
Tablespace altered.
SQL> select name,bytes/1024/1024,status from v$tempfile;
NAME BYTES/1024/1024 STATUS
------------------------------ --------------- -------
/oradata/seven/temp01.dbf 30 ONLINE
由于场景是DG环境，所以temp的name和bytes的值最好保持主备库一致，方便以后做Switchover；
至于导致ORA-01187错误的主要诱因，还是不明，也没有找到相关的文档；