在我们对Oracle做EXP的过程中,可能会经常遇到EXP-00091 Exporting questionable statistics.的信息,其实它就是exp的error message,它产生的原因是因为我们exp工具所在的环境变量是的NLS LANG中的NLS_CHARCATERSET不一致引起的。但需要说明的是,exp-00091这个error对所生成的dump文件没有影响,生成的dump文件还可以正常imp。
下面我们来解决这个问题,让其不在出现:
第一步: 查看DB中的NLS_CHARACTERSET的值(提供两种方法): 查询NLS_CHARACTERSET的值: select * from nls_database_parameters t where t.parameter='NLS_CHARACTERSET' or select * from v$nls_parameters where parameter='NLS_CHARACTERSET'; SQL> select * from v$nls_parameters where parameter='NLS_CHARACTERSET'; PARAMETER VALUE ----------------------- ---------------------------------------------- NLS_CHARACTERSET ZHT16BIG5 第二步: 根据第一步查出的NLS_CHARACTERSET(ZHT16BIG5)來設定exp的環境變量: WINNT> set NLS_LANG=AMERICAN_AMERICA.ZHT16BIG5 进行设定后,在环境变量中查看NLS_LANG的值是否一致,如果不一致可在环境变量中手中修改。 LINUX> export NLS_LANG=AMERICAN_AMERICA.ZHT16BIG5
附上exp-91的oracle error message 解決方案說明:
oerr exp 91 00091, 00000, "Exporting questionable statistics." // *Cause: Export was able export statistics, but the statistics may not be // usuable. The statistics are questionable because one or more of // the following happened during export: a row error occurred, client // character set or NCHARSET does not match with the server, a query // clause was specified on export, only certain partitions or // subpartitions were exported, or a fatal error occurred while // processing a table. // *Action: To export non-questionable statistics, change the client character // set or NCHARSET to match the server, export with no query clause, // export complete tables. If desired, import parameters can be // supplied so that only non-questionable statistics will be imported, // and all questionable statistics will be recalculated.