Script sniplet to differentiate between cdb and pdb environment settings in a shell script

This little sniplet could be used if you find yourself in a situation where you need to differentiate between the cdb environment and the pdb environment on a server using multitenant setup.

I am setting a commonly used alias for the usage of sqlplus called "sql" depending on the ORACLE_SID being set to the cdb or the pdb.

It differs slightly since I you can only do a bequath session when connecting to the former, and not the latter:

When connecting to the pdb as sysdba, you need to go through the listener, and therefore supply the password.

When connecting to the cdb you can do a so called bequeath session and connect directly to the oracle instance through IPC.

read -p 'Will you be administrating the cdb or the PDB? ' container
case $container in
        CDB|cdb)
        . $ORACLE_HOME/cdb_settings.env;
        alias sql='sqlplus / as sysdba';;
        PDB1|pdb1)
        . $ORACLE_HOME/pdb1.env;
        alias sql='sqlplus sys@pdb1 as sysdba';;
        *) echo "You must select cdb or pdb1";
         exit 1;;
esac