Quick Reference for Oracle Database

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Oracle Database Startup Phases...

Nomount -- oracle opens and read init.ora file, start the background process.

Mount -- open and read control file for data files locations etc...

Open --  it accesses all of the data files associated with the database

Opening the Database in Restricted Mode

It will only allow users with special privileges to access the database like System administrator or DBAs, even though the database is technically open.

SQL> startup restrict

===========

Database start in RAC:

srvctl start database -d DB_NAME

##### To start instance in mount state #####

srvctl start instance -d <DB_NAME> -i <INSTANCE_NAME> -o mount

srvctl start instance -d <DB_NAME> -i <INSTANCE_NAME>

###### To mount database #####

srvctl start database -d <INSTANCE_NAME> -o mount

Command to Check Status:

srvctl status database -d DB_NAME

Command to Stop database Instance:

srvctl stop database -d <DB_NAME> -o immediate

===========

How to check datafiles Path or locations:

SQL> SELECT NAME FROM V$DATAFILE;

NAME

-------------------------------------------------------------------------------------

/home/oracle/app/oracle/oradata/orcl/system01.dbf

/home/oracle/app/oracle/oradata/orcl/sysaux01.dbf

/home/oracle/app/oracle/oradata/orcl/undotbs01.dbf

/home/oracle/app/oracle/oradata/orcl/users01.dbf

/home/oracle/app/oracle/oradata/orcl/example01.dbf

/home/oracle/app/oracle/oradata/orcl/APEX_1930613455248703.dbf

/home/oracle/app/oracle/oradata/orcl/example02.dbf

7 rows selected.

SQL>

SQL> select file_name from dba_data_files;

FILE_NAME

--------------------------------------------------

/home/oracle/app/oracle/oradata/orcl/users01.dbf

/home/oracle/app/oracle/oradata/orcl/undotbs01.dbf

/home/oracle/app/oracle/oradata/orcl/sysaux01.dbf

/home/oracle/app/oracle/oradata/orcl/system01.dbf

/home/oracle/app/oracle/oradata/orcl/example01.dbf

/home/oracle/app/oracle/oradata/orcl/APEX_19306134

55248703.dbf

/home/oracle/app/oracle/oradata/orcl/example02.dbf

7 rows selected.

SQL>

Some more useful links:

How to Study and Prepare for Exams

How to Enable or Disable Archive log mode in oracledatabase 11g

How to export query output to Excel in Oracle SQLDeveloper

How to check notepad++ backup files

Regards,

TechOrNontech Team