while running alter databse open i am getting follwoing erroralter database open
ERROR at line 1:
ORA-00600: internal error code, arguments: [kcratr_nab_less_than_odr], ,
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You can't cause an ORA-00600 "naturally"; it's a generic exception that covers internal Oracle exceptions. So, unless you know of an Oracle bug that causes this or want to deliberately corrupt your database you've got no chance.