What are the Startup sequences of oracle Database

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Summary: in this tutorial, you will learn how to use the Oracle STARTUP command to start an Oracle Database instance.


Startup stages :

1)Startup nomount

2)Startup mount

3)Startup open or startup


1)Startup nomount:

  • Only instance started.
  • Spfile or pfile read
2)Startup mount:

  • To check the instance+ Controlfile




3)Startup open or startup

  • To check the instance + Controlfile + All files(datafile+redolog)



By using alter commands are Startup.

  • Alter database mount
  • Alter database dismount
  • Alter database open
  • Alter database open
  • Alter database Close
  • Alter database open read only
  • Alter database open read write 
  • Alter system enable restricted session
  • Alter system disable restricted session
                                                     Thanks for your time!!!


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