ORA-31622: premature end of file at block string
Cause: d either by a corrupted Data Pump export dump file or by an Oracle internal error. This message should be preceded by another message identifying the name of the dump file in question.
Action: Retry the Data Pump import operation. Contact Oracle Support Services if the problem persists.
发生ORA-31622错误，表示数据库在等待一个数据块时，收到了文件结束信号。
ORA-31622: premature end of file at block string
Cause: The indicated data block was not found at the end of the dump file.
Action: Check the file is a valid export dump file and is not corrupted.
ORA-31622错误通常会发生在操作过程中出现网络错误的情况下，当数据库发出一条网络指令要求传输一定数量的数据，如果传输过程中发生错误或中断，那么就会发生ORA-31622错误。
1. 检查数据库与相关文件是否已正常启动，如果未启动则立即启动；
2. 检查数据库活动日志文件，找到问题原因；
3. 尝试重新执行所有操作，如果出现问题则重复步骤2；
4. 如果问题未得到解决，则可以考虑到Oracle官方技术支持获取帮助。