Three authentication mechanisms for Oracle databases

About Super Admin login does not require a password because:

Three types of authentication mechanisms for databases:
Operating system validation (for users with SYSDBA and Sysopera)
Password file validation (for users with SYSDBA and Sysopera)
Database authentication (normal user)

Because the password is not required is not secure, so generally in the computer Management of the user group ORA_DBA
Delete the administrator and enter the password after the deletion.

Start monitoring: Lsnrctl start
View monitoring: Lsnrctl status
Stop listening: Lsnrctl stop

1. Oracle data Server includes: instance process and database;
Instance processes include: Memory structure (SGA) and background process (Pmon (process monitoring), Smon (System Monitor, 3 seconds of Space), DBWR (dirty data processing), LGWR (writes redo buffer file will log), Ckpt (checkpoint, synchronization data, first write log, dirty data) and other processes);
The database includes: Data file, control file, redo log file, three is necessary, as for parameter file, password file, archive file is optional, depending on the state of the database;
2. PGA: Includes user process and server process,user process to communicate with Oracle's instance through server process.
3, sga=share pool+database buffer cache+redo log buffer + other structures (large Pool,java pool optional)
Shared_pool=library cache (SQL shared, buffered SQL execution plan with least recently used algorithm) + data dictionary cache (row cache, data dictionary);
Database buffer Cache (db_cache_size):Oracle is the most basic data read and write unit in block size
Redo Log Buffer cache:
4. Change the parameters:
alter system set SHARED_POOL_SIZE=64M;
alter system set DB_CACHE_SIZE=64M;
alter system set LARGE_POOL_SIZE=64M;
5. OS Authentication User:
Create User ID
Create Group (Ora_dba,ora_databasename_dba,ora_oper,ora_databasename_oper)
Add user ID to group ID
Edit Sqlnet.ora (sqlnet.authentication_services= (NTS))
6, forget the System/sys password:
Remove E:\oracle\product\10.2.0\db_1\database\pwdtestdb.ora;
Use command: orapwd file=d:\pwdtestdb.ora password=admin1 entries=10; set Password to admin1;
Dolly Mix
sqlplus/@testdb as Sysdba
ALTER user SYS identified by new password;
Alter user system identified by new password;

7, block (blocks) extend (disk area) segment (segment) tablespace (table space)
8, Network Service configuration information recorded in the D:\oracle\product\10.2.0\db_1\NETWORK\ADMIN\tnsnames.ora file
Start command for database
1. Start TNS monitoring
C:\Documents and Settings\administrator>lsnrctl start
2. Start Oracle Services
C:\Documents and Settings\administrator>net start ORACLESERVICEORCL
3. Log in as Sysdba
Sql> Connect System as SYSDBA
4. Start Isqlplus
C:\Documents and Settings\administrator>isqlplusctl start
5. Start the database control
C:\Documents and Settings\administrator>emctl start Dbconsole
If a startup error is made, it is likely that the IP address has been modified to take the following actions:
Set Oracle_hostname= host Name
Emca-config Dbcontrol DB for the appropriate configuration.
6, http://localhost:1158/em/

< Turn on console output >
1. Show All
Serveroutput OFF
2. Set Serveroutput on
Startup and Shutdown modes
Several ways to start and shut down Oracle databases
There are several ways to start:
1, Startup Nomount
Non-installation boot, this way startup executable: Rebuild the control file, rebuild the database

Read the Init.ora file and start instance, which starts the SGA and background process, which requires only init.ora files.

2. Startup Mount DBName
Installation starts, this way starts under executable:
Database log archiving,
Database Media Recovery,
Bring the data file online or offline,
Relocate the data file, redo the log file.
Execute "nomount", then open the control file, confirm the location of the data file and the online log file,
However, the data files and log files are not checked for validation at this time.

3. Startup Open dbname
Execute "nomount" first, then execute "Mount", and then open all the database files including the redo log file,
This way you can access the data in the database.

4, startup, equal to the following three commands
Startup Nomount
ALTER DATABASE Mount
ALTER DATABASE Open

5, startup restrict
Constrained mode start
This way the database can be started, but only users with certain privileges are allowed access
When a non-privileged user accesses, the following prompt appears:
ERROR:
Ora-01035:oracle only allow users with RESTRICTED SESSION permissions to use

6. Startup force
Forced start mode
When the database cannot be closed, you can use startup force to complete the shutdown of the database
Close the database first and then execute the normal startup database command

7. Startup pfile= parameter file name
Start mode with initialization parameter file
Read the parameter file first, and then start the database by setting it in the parameter file
Example: Startup Pfile=e:\oracle\admin\oradb\pfile\init.ora

8, startup EXCLUSIVE
============================================
There are three ways to start:
1. Shutdown normal
Shut down the database in the normal way.

2, Shutdown immediate
Close the database immediately.
Shutdown immediate is executed in SVRMGRL and the database is not shut down immediately.
Instead of shutting down (terminating the session, freeing the session resource) after Oracle performs some cleanup work,
When you cannot close a database by using shutdown, shutdown immediate can complete the operation of the database shutdown.

3, Shutdown abort
Directly shuts down the database, and the session that is accessing the database is suddenly terminated.
If a large number of operations are executing in the database, it takes a long time to restart the database after shutdown abort is executed.

Three authentication mechanisms for Oracle databases