ORACLE: How to check INSTANCE restart history?

This is an easy one that will save you going through alert logs.

col STARTUP_TIME format a50
SELECT STARTUP_TIME , INSTANCE_NUMBER  
	FROM dba_hist_database_instance 
	where  STARTUP_TIME > sysdate -365
ORDER BY startup_time DESC;
 
  
STARTUP_TIME                                       INSTANCE_NUMBER
-------------------------------------------------- ---------------
15-JUN-21 12.32.08.000 PM                                        2
15-JUN-21 12.01.36.000 PM                                        1

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