文档解释
ORA-07459: cannot restore the RESOURCE_MANAGER_PLAN parameter
Cause: An attempt was made to internally restore the RESOURCE_MANAGER_PLAN parameter to the value before it was internally set. This failed because the current plan was set by the user and therefore did not need to be restored.
Action: No action needed.
这是一个Oracle数据库的错误，它表明无法恢复RESOURCE_MANAGER_PLAN参数（Resource Manager计划）。
官方解释
ORA-07459:cannot restore the RESOURCE_MANAGER_PLAN parameter
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Cause: An attempt was made to restore a Resource Manager plan by connecting to the server, but the plan was already restored by another session.
Action: No action is required.
常见案例
这个错误通常发生在尝试连接到服务器并尝试恢复Resource Manager计划，但是另一个会话已经恢复了该计划。
正常处理方法及步骤
此错误通常不需要任何操作，不需要采取任何措施。然而，用户应该检查其正在连接的服务器，以确保该错误不会发生在其他情况下。如果该错误是由其他会话恢复Resource Manager计划而引起的，则可以忽略此消息。
