Solutions are Here

Error :

     ORA-12543: TNS:destination host unreachable

Solution:

    Open CMD Try the below Methods

           echo %ORACLE_HOME%

           echo %ORACLE_SID%

           set oracle_sid=<<Service name>> ( Example :    set oracle_sid=ORCL )

           sqlplus / as sysdba

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Solutions are Here

Question:

       OPEN the PLUGGABLE DATABASE (PDB) 

Solution:

        Connect the Database in  SQL Developer  with DB Credential

        Run the below Query in SQL Developer 

                  SELECT name, open_mode FROM v$pdbs;

                  ALTER PLUGGABLE DATABASE PDBORCL OPEN;

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