Oracle error- ORA-00845: MEMORY_TARGET not supported on this system

Oracle error

ORA-00845: MEMORY_TARGET not supported on this system

Cause: The MEMORY_TARGET parameter was not supported on this operating system or /dev/shm was not sized correctly on Linux.

Action: Refer to documentation for a list of supported operating systems. Or, size /dev/shm to be at least the SGA_MAX_SIZE on each Oracle instance running on the system.

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ORA-01156: recovery or flashback in progress may need access to files

Oracle error

ORA-01156: recovery or flashback in progress may need access to files

Cause: Either media recovery, instance recovery, or flashback was in progress. The recovery or flashback in progress may need the files to which this operation is being applied.

Action: Wait for recovery or flashback to complete.

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ORA-01155: the database is being opened, closed, mounted or dismounted

Oracle error

ORA-01155: the database is being opened, closed, mounted or dismounted

Cause: The requested operation needs the instance to be in a particular state but the state is being changed.

Action: Wait for the open, close, mount, or dismount to complete then retry the operation. If necessary, a SHUTDOWN ABORT will always work.

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