Oracle 12c, I see that users must start with a double pound
sign, like ##c
I do when my instance looks up due to the log archive
destination getting full? I see this message,
indicating that the directory is full:
Answer: Oracle 12c has started
making the multi-tenant the default behavior, and
Oracle makes a distinction in multitenant databases for
local vs. "common" user ID's:
When creating a local (pdb) user, we must use the
"container" clause. Here, we move from the container
database to the pdb database (using the "alter session set
container" clause), and then create a pdb user:
- COMMON USERS: Common user
ID's must always be created at the CDB level and start
with a C## or c## prefixes. Oracle does not recommend
that common users be used as schema owners.
- LOCAL USERS: Local
users can only be created at the PDB layer; also must
use the CONTAINER clause set to CURRENT for the user to
alter session set container=my_pdb_name;
create user fred identified by
Local users differ from common users in these respects:
- Local user ID's cannot create user ID's or grant
Common user ID's are created with the "container=all'
syntax, and a container user ID should not be used to create
schema tables. Also, only common users are capable of
navigating between PDB's.
- Local user ID's can grant local user accounts
- Local user ID's must be unique within the
- Local user ID's can be granted access to a common
- Local user ID's can be editions-enabled.
Also, see my notes on
creating common users without the c##_prefix.
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