-902: I/O error 

Explanation:

While an SQL statement was being processed, a read or write operation had to be performed on the data area or log area. This operation could not be executed successfully. The following reasons are possible:

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       1.      A SHUTDOWN was performed in the meantime.

       2.      A disk is defective.

User Action:

In some cases, the error message contains an additional description of the error which must be interpreted according to the operating system being used.

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       1.      Use Database Manager to start the database instance.

       2.      Once the disk error has been corrected, the database instance must be restored.