ORA-12162 TNS:net service name is incorrectly specified

Problem:

After you installed ORACLE database,if you want to connect database with sqlplus,you get a this error

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*ORA-12162 TNS:net service name is incorrectly specified
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Solution:

You have to add your database SID in your '.bash_profile' or if you use Solaris file is '.profile'

export ORACLE_SID=<SID>


Good luck:))