You notice that the performance of your production 24x7 Oracle 12c database has significantly degraded.
Sometimes, you are not able to connect to the database instance because it hangs.
How can you detect the cause of the degraded performance?

Your database supports an OLTP workload. Examine the output of the query:

To ensure faster instance recovery, you set the FAST_START_MTTR_TARGET initialization parameter to
30.
What is the effect of this setting on the database?

You are administering a multitenant container database (CDB) that contains multiple pluggable databases (PDBs). You are connected to cdb$root as thesys user. You execute the commands:
SQL> CREATE USER C##ADMIN IDENTIFIED BY orcll23;
SQL> CREATE ROLE C##CONNECT;
SQL> GRANT CREATE SESSION, CREATE TABLE, SELECT ANY TABLE TO
C##CONNECT;
SQL> GRANT C##CONNECT to C##ADMIN CONTAINER=ALL;
Which statement istrue about the c##connect role?

Which statement is true aboutthe loss or damage of a temp file that belongs to the temporary tablespace of a pluggable database (PDB)?

Automatic Undo Management is enabled for your database. You want a user to retrieve metadata and historical data for a given transaction or for transactions in a given time interval.
Which three are prerequisites to fulfill this requirement?