| <!-- @page { margin: 0.79in } P { margin-bottom: 0.08in | | | | is restored, you try to mount the database, but fail to |
| } --> | | | | do so. An error message is displayed as a result, that |
| Most of you who use Oracle database regularly must | | | | is: |
| have faced problems in mounting the Oracle database | | | | "DBV-00200: Block, dba 4289132, already marked |
| while trying to access them. The primary reason for | | | | corrupted |
| such situations is the logical corruption in the database | | | | DBV-00200: Block, dba 4309228, already marked |
| files, which are, in turn, saved in the physical storage | | | | corrupted" |
| components referred as blocks. Oncecorruption is | | | | Cause: |
| encountered in the database, it becomes inaccessible, | | | | The primary cause for such erroneous situation is that |
| which makes all the records inaccessible as well. | | | | the a corrupted block has been allocated to an Oracle |
| There could be any number of database corruption | | | | database component. Other reason for such case is |
| such as human errors, virus infections, improper or | | | | that the database has corrupted due to power outage. |
| abrupt system shutdown, bugs in the existing | | | | Resolution: |
| application version, etc. In such cases, you should try to | | | | To resolve such problem, you should check if the |
| find out the exact cause of corruption, and try to | | | | database has an updated and clean backup. If yes, |
| resolve the problem. If you are unable to fix the | | | | then you should restore the database from its backup. |
| problem, then you should check the database backup. | | | | Now, try to mount the database. It should be fine now. |
| Try to restore from the backup, if it is updated. If any | | | | However, if the backup is not updated or you still face |
| of these methods are insufficient to resolve the issue, | | | | the similar problems then you should use a third-party |
| then you should use a third-party Oracle database | | | | Oracle database recovery software to recover |
| recovery software to recover Oracle database. | | | | Oracle database. Such DBF recovery tools are |
| Consider a scenario wherein you are working on an | | | | read-only in nature that do not overwrite the existing |
| Oracle database. Suddenly, there is a power outage | | | | database while scanning it. |
| and the system shuts down abruptly. When the power | | | | |