ORA-00604: error occurred at recursive SQL level 1
ORA-00376: file 4 cannot be read at this time
ORA-01110: data file 4: '+DATA/orcldb/datafile/undotbs2.343.817729081'
Startup nomount
select status, file# from v$datafile where status='recover';
status file#
------- ------
recover 4
set autorecovery on
recover datafile 4
alter database datafile 4 online;
shutdown immediate
lsnrctl stop
startup
lsnrctl start