ORA-01034 ORACLE not available Cause: Oracle was not started. Possible causes include the following: * The SGA requires more space than was allocated for it. * The operating-system variable pointing to the instance is improperly defined. Action: Refer to accompanying messages for possible causes and correct the problem mentioned in the other messages. If Oracle has been initialized, then on some operating systems, verify that Oracle was linked correctly. See the platform-specific Oracle documentation.
内核损坏.
内存corrupted
system corrupted
undo corrupted
控制文件丢失
没有参数文件
授权不够
bug.
.......
* The operating-system variable pointing to the instance is improperly defined. Action: Refer to accompanying messages for possible causes and correct the problem mentioned in the other messages. If Oracle has been initialized, then on some operating systems, verify that Oracle was linked correctly. See the platform-specific Oracle documentation.
你说的不可用，是oracle宕机了，还是企业应用不能用oracle数据库呢？