database - Oracle Database12c ORA 01918 and connection error -

I have installed Oracle 12c and I have trouble creating my first database and using it. I run the SQL developer and use the "HR" user but it keeps telling me that the account is locked. I searched for stackoverflow answers and official doctors and tried to unlock it:

  password identified by ACCOUNT unblock ALTER USER HR;  

But without success, I got the error ORA01918, which means that the user does not exist.

I tried to use the user created in the installation (SYSDBA as SYS), but then it says that the user / password is wrong. I'm pretty sure I installed Oracle 12c on my system properly, which is Windows 8.1 x64.

What should I do? Please help me.

Whatever I do not understand, is the weather or does not the "database" word match the "schema" of MySQL? "Connection" is to connect to a specific database, yes? Thank you.

How did you configure your database? Have you checked the option for pluggable database ? If so, please make sure that you do not enter PDB and CDB .

Please read.

By default, pre-installed users such as SCOTT , hr etc remain in the database Is and not in the pluggable database .

tnsnames.ora

To add PDB details, edit your tnsnames.ora file. For example,

  PDBORCL = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP) (HOST = localhost) (port = 1521)) (CONNECT_DATA = (server = defined) (SERVICE_NAME = pdborcl ))  

Open all PDBs

to open all / specific PDBs immediately after logon, after a STARTUP System level triggers in CDB.

Since, PDBs are not open with a CDB start-up:

  Shut down immediately; start up; SQL & gt; V $ pdbs from SELECT name, open_mode; Name OPEN_MODE ------------------------------ ---------- PDB $ Seed Read Only PDBP6 Mounts < />  ", and then execute:  
  Open the trigger after starting the database, open_pdbs start 'open all database executed immediately'; end open_pdbs ;  
  SQLPLUS / AS SYSDBA   
 The most common misconception is about using "SQLPLUS / AS SYSDBA".  
 Since We have checked the option to create a single  CDB , then the "SQLPLUS / AS SYSDBA" command will always be logged in Usually the developers used to unlock the "SCOTT" account after logging in as a SYSDBA. But here's the trick:  
  "SCOTT" and other samples Schema is in PDB and not in the CDB  Therefore, you need to login into PDB as sysdba.  
  sqlplus SYS / password @ PDBORLSssdbacxl> Optionally User recognized by Scott Account Tiger Lock; Sqlplus Scott / Tiger @ PDBCRL SQL & gt; Show users; USER is "SCOTT"