Which two functions are performed by a listener?

Your database instance is started with a PFILE.
Examine these parameters:

You want to increase the size of the buffer cache.
Free memory is available to increase the size of the buffer cache.
You execute the command:
SQL> ALTER SYSTEM SET DB_CACHE_SIZE=1024M;
What is the outcome?

Examine this command and some partial output:

Why does the DB01.abc.com service show unknown status?

Which three statements are true about inner and outer joins? (Choose three.)

Examine the description of the SALES1 table:

SALES2 is a table with the same description as SALES1.
Some sales data is duplicated in both tables.
You want to display the rows from the SALES1 table which are not present in the SALES2 table.
Which set operator generates the required output?