DBA CHANAKYA

STARTING YOUR ORACLE DATABASE

       To start your database in any environment you should first know what is the database name.

        As soon as you install your database using DBCA or Creating it manually the entry would remain in the         

        oratab file.

        The oratab file is normally located in the:
       - /var/opt/oracle directory for Solaris platform 
       - /etc  directory for most of the other platforms

        SAMPLE ORATAB

        

        [oracle@oraupgrade ~]$ cat /etc/oratab

#Backup file is  /appl/app/oracle/product/12.1.0/grid/srvm/admin/oratab.bak.oraupgrade line added by Agent
#



# This file is used by ORACLE utilities.  It is created by root.sh
# and updated by either Database Configuration Assistant while creating
# a database or ASM Configuration Assistant while creating ASM instance.

# A colon, ':', is used as the field terminator.  A new line terminates
# the entry.  Lines beginning with a pound sign, '#', are comments.
#
# Entries are of the form:
#   $ORACLE_SID:$ORACLE_HOME:<N|Y>:
#
# The first and second fields are the system identifier and home
# directory of the database respectively.  The third filed indicates
# to the dbstart utility that the database should , "Y", or should not,
# "N", be brought up at system boot time.
#
# Multiple entries with the same $ORACLE_SID are not allowed.
#
#
+ASM:/appl/app/oracle/product/12.1.0/grid:N:            # line added by Agent
#ORAUPGRADE:/u01/app/oracle/product/11.2.0/dbhome_1:N:          # line added by Agent
ORAUPGRADE:/appl/app/oracle/product/12.1.0/dbhome_1:N:          # line added by Agent
[oracle@oraupgrade ~]$

Note : Do not include names which are hashed out. 

    

        As soon as you login you need to set the environment using .oraenv

[oracle@oraupgrade ~]$ . oraenv
ORACLE_SID = [ORAUPGRADE] ? ORAUPGRADE
The Oracle base remains unchanged with value /appl/app/oracle

Now connect to sqlplus and start the database

SQL> startup
ORACLE instance started.

Total System Global Area 1536602112 bytes
Fixed Size                  2288680 bytes
Variable Size             553649112 bytes
Database Buffers          973078528 bytes
Redo Buffers                7585792 bytes
Database mounted.
Database opened.
SQL>

Screen shot for Reference :