ORA-01138: database must either be open in this instance or not at all

Oracle error

ORA-01138: database must either be open in this instance or not at all

Cause: The requested operation can not be done when the database is mounted but not open in this instance, and another instance has the database open.

Action: Execute the operation in an open instance, open the datbase in this instance, or close the database in the other instances.

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ORA-01128: cannot start online backup - file string is offline

Oracle error

ORA-01128: cannot start online backup - file string is offline

Cause: An attempt to start an online backup found that one of the files is offline.

Action: Bring the offending files online and retry this command or do a cold backup.

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ORA-01136: specified size of file string (string blocks) is less than original size of string blocks

Oracle error

ORA-01136: specified size of file string (string blocks) is less than original size of string blocks

Cause: A file size was specified in the AS clause of ALTER DATABASE CREATE DATAFILE, and the size was smaller the the size needed

Action: Create the file with a larger size.

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