可能产生的错误

ORA-39095: Dump file space has been exhausted: Unable to allocate 8192 bytes
Job "SYSTEM"."SYS_EXPORT_SCHEMA_01" stopped due to fatal error at 13:34:40

expdp时parallel不当也会引起ORA-39095
2008-09-24 15:01

在expdp做导出的时候会有碰到ora-39095的错误，引起这个错误的原因有两种。一一说来
先看官方的解释：
ORA-39095: Dump file space has been exhausted: Unable to allocate string bytes
Cause: The Export job ran out of dump file space before the job was completed.
Action: Reattach to the job and add additional dump files to the job restarting the job.
从字面意思就解释了第一种原因，那就是：空间不够了。解决方法也简单，多来点空间。
还有第二中原因：当使用了PARALLEL但是dumpfile却只有一个或小于parallel数，下面是官方的说明：

Oracle? Database Utilities
10g Release 2 (10.2)
2 Data Pump Export
PARALLEL=integer
The value you specify for integer should be less than, or equal to, the number of files in the dump file set (or you should specify substitution variables in the dump file specifications).
Because each active worker process or I/O server process writes exclusively to one file at a time, an insufficient number of files can have adverse effects. Some of the worker processes will be idle while waiting for files, thereby degrading the overall performance of the job.(第一个原因是影响性能)
More importantly, if any member of a cooperating group of parallel I/O server processes cannot obtain a file for output, then the export operation will be stopped with an ORA-39095 error. (ora-39095的成因)Both situations can be corrected by attaching to the job using the Data Pump Export utility, adding more files using the ADD_FILE command while in interactive mode, and in the case of a stopped job, restarting the job.
说白话点就是：parallel io server processes写文件不能同时写一个，如果只有一个dumpfile(或少于parallel)就会影响性能。不但如此，当一个io server process在等待从而不能写dumpfile的时候就会报ora-39095
要解决：expdp ATTACH 连上作业然后减少parallel或者增加dumpfile
从起源解决的话就是：指定parallel的时候就要指定至少同样多的dumpfile或者使用类似下面的命令(注意红字)：
expdp hr/hr DIRECTORY=dpump_dir1 LOGFILE=parallel_export.log JOB_NAME=par4_job DUMPFILE=par_exp%u.dmp PARALLEL=4