ORA-03113：end-of-file on communication channel  
  
　　产生原因：通讯不正常结束，从而导致通讯通道终止  
  
　　解决方法：1>.检查是否有服进程不正常死机，可从alert.log得知  
  
　　2>.检查sql*Net Driver是否连接到ORACLE可执行程序  
  
　　3>.检查服务器网络是否正常，如网络不通或不稳定等  
  
　　4>.检查同一个网上是否有两个同样名字的节点  
  
　　5>.检查同一个网上是否有重复的IP地址  
  
　　相应的英文如下：  
  
Cause:An unexpected end-of-file was processed on the communication channel.The problem could not be handled by the Net8,two task,software.This message could occur if the shadow two-task process associated with a Net8 connect has terminated abnormally,or if there is a physical failure of the interprocess communication vehicle,that is,the network or server machine went down.  
  
Action:If this message occurs during a commection attempt,check the setup files for the appropriate Net8 driver and confirm Net8 software is correctly installed on the server.If the message occurs after a connection is well established,and the error is not due to a physical failure,check if a trace file was generated on the server at failure time.Existence of a trace file may suggest an Oracle internal error that requires the assistance of customer support.  
ORA-00942:table or view does not exist  
  
产生原因：这是由于装载的表或视图不存在，多半是CATEXP.SQL还没有运行，无法执行Export视图,如果CATEXP.SQL已经运行，则可能是版本错误。  
  
　　解决方法：因为Import和Export共享的一些视图是通过运行CATEXP.SQL来装载的（它们具有相同的视图），并不生成单独的CATEXP.SQL，因而造成视图与Export代码不同步，较难保持彼此之间的兼容，用户就必须建立自己的Export应用，从而避免ORA-00942的错误。  
  
　　相应的英文如下：
  
Cause:The table or view entered does not exist,a synonym that is jnot allowed here was used,or a view was referenced where a table is required.Existing user tables and views can be listed by querying the data dictionary.Certain privileges may required to access the table.If an application returned this message,the table the application tried to access does not exist in the database,or the application does not have access to it.  
  
Action:Check each of the following:  
  
The spelling of the table or view name.  
  
That a view is not specified where a table is required  
  
That an existing table or view name exists.  
  
Contact the database administrator if the table needs to be created or if user or application priviledes are required to access the table.  
  
Also, if attempting to access a table or view in another schema,make certain thecorrect schema is referenced and that access to the object is granted.