How to restore an Oracle database with only intact data files?

1. Recreate the initialization file. Important Parameters include
Control_files, db_name, instance_name, background_dump_dest, core_dump_dest, user_dump_dest ,\
Db_block_size = 8192, db_cache_size, db_domain, large_pool_size, pga_aggregate_target, shared_pool_size,
Sort_area_size, undo_management, undo_retention, undo_tablespace, etc.
You can create an initial parameter file for modification in the following ways:
@ Obtain from the backup parameter file
@ Get from other normal Oracle instances and run the following command
Create pfile = 'parameter file path and name' from spfile
 
You need to modify the file after obtaining it. Note that this file is very important for recovery and must be checked correctly.
Check whether the directory set by parameters such as background_dump_dest, core_dump_dest, and user_dump_dest exists.

2. Modify the Listener Configuration File and check the database parameters of the listener.

3. Set the environment variable ORACLE_SID at the system level.

4. Create an instance
OraDim-NEW-SIDSid-Startmode m

5. Create an Oracle Password File
OraPwd file = Oracle_HOME/database/pwdSid. Ora password = *****
The location of the password file must be correct. Otherwise, an error will be reported in Step 7.

6. Start the instance
@ Sqlplus "/as sysdba"
If your parameter file is placed in the default location and the name meets the standard requirements, run
@ Startup nomount;
Otherwise
@ Startup nomount pfile = 'parameter file path and name ';

7. Create a control file
Sample script
Create controlfile set database"Db_name"RESETLOGS NOARCHIVELOG
MAXLOGFILES 50
MAXLOGMEMBERS 5
MAXDATAFILES 100
MAXINSTANCES 1
# MAXLOGHISTORY 453
LOGFILE
GROUP 1 'Log file path and name' SIZE 100 M,
GROUP 2 'Log file path and name' SIZE 100 M,
GROUP 3 'Log file path and name' SIZE 100 M
DATAFILE
'Data file path and name ',
....................
...................
Character set ZHS16GBK;

8. Open the database
Alter Database Open resetlogs;

9. Add temporary files to the temporary tablespace
Because the creation of temporary files is not included in the script for creating Control Files
Therefore, you need to manually add temporary files to the temporary tablespace.
Otherwise, some commands may run abnormally.
Alter tablespace "TEMP"
Add tempfile 'C: \ ORACLE9I \ ORADATA \ SHARK \ temp01.dbf' [reuse] SIZE 200 M

At this point, your recovery is complete. You can run some commands to check