Make changes in PDB$SEED Read only database in Oracle 12c
Suppose if you have to update in your PDB$SEED database something by opening it in READ WRITE Mode and do changes on it then close.
In my case my patch is failed then i have to rerun the datapatch verbose. For that i need to modify one entry in PDB$SEED database.
1. Connect with ROOT Container with sysdba privileges and move to PDB$SEED container.
SQLPLUS / as sysdba
ALTER SESSION SET CONTAINER = PDB$SEED;
2. Verify that you are in PDB$SEED
3. You need to set the hidden parameter
alter session set "_oracle_script" = true;
4. You need to close PDB$SEED and open in read write state.
alter pluggable database pdb$seed close;
alter pluggable database pdb$seed open read write;
5. Make changes as needed by you.
6. Then shutdown and open in tin READ ONLY state.
alter pluggable databsae pdb$seed close;
alter pluggable database pdb$seed OPEN READ ONLY;
7. Disable the Hidden parameter
alter session set "_oracle_script"=FALSE;