without Control files and redo log files Recover database

If your database control file and redo log file files is lost,to recover the database without these:--

Startup the database with the initialization file. As we do not have the control files, start the database in no mount state.
SQL> startup nomount
ORACLE instance started.
Total System Global Area 209715200 bytes
Fixed Size 1248140 bytes
Variable Size 75498612 bytes
Database Buffers 130023424 bytes
Redo Buffers 2945024 bytes
SQL>Check the path of control files.SQL> show parameter control
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
control_file_record_keep_time integer 7
control_files string K:\ORCL10G\CONTROL\CONTROL01.C
TL, K:\ORCL10G\CONTROL\CONTROL
02.CTL, K:\ORCL10G\CONTROL\CON
TROL03.CTL
Having the details of all the data files at hand recreate the control files.SQL> CREATE CONTROLFILE REUSE DATABASE "ORCL10G" RESETLOGS NOARCHIVELOG
MAXLOGFILES 16
MAXLOGMEMBERS 3
MAXDATAFILES 100
MAXINSTANCES 8
MAXLOGHISTORY 292
LOGFILE
GROUP 1 'K:\ORCL10G\LOG\REDO01.LOG' SIZE 50M,
GROUP 2 'K:\ORCL10G\LOG\REDO02.LOG' SIZE 50M,
GROUP 3 'K:\ORCL10G\LOG\REDO03.LOG' SIZE 50M
DATAFILE
'K:\ORCL10G\DATA\SYSTEM01.DBF',
'K:\ORCL10G\DATA\UNDOTBS01.DBF',
'K:\ORCL10G\DATA\SYSAUX01.DBF',
'K:\ORCL10G\DATA\USERS01.DBF',
'K:\ORCL10G\DATA\EXAMPLE01.DBF',
'K:\ORCL10G\DATA\UNDOTBS02.DBF'
CHARACTER SET WE8MSWIN1252;
Control file created.
Note the RESETLOGS option in the create control file script. This will reset the logs and synchronizes the SCN between the database files, control files and redo log file. Oracle will re-create the redo log files when the database is opened with resetlogs options.
Once the control file is created, try mounting the database. If the database mounts well then everything seems to be fine.
SQL> alter database mount;
Database altered.
The database mounted successfully. Open the database with resetlogs option.SQL> alter database open resetlogs;
Database altered.
Here we go. The database opened successfully. The only point to consider is that of the data loss. The data in the redo log files, as it existed before the loss, will be lost. Hence the data loss here could be minimum.
Conclusion :
1. Always multiplex the Control files and Redo log files.
2. Have a consistent backup of the database.