A.Kay is already connected elsewhere and attempting to log in again.

B.connect_timeout is too small to allow a connection to occur.

C.All users are blocked because max_user_connections is accumulated over the host account information.

D.Bob has max_user_connections set to zero, which blocks all his connections.

E.Joe has exceeded the max_user_connections global limit.

A.There are three indexes on the table.

B.There is a redundant index on the dept_no column.

C.There is a redundant index on the emp_no column.

D.The values on the emp_no column must be unique.

E.The selectivity of the dept_no column is the best of the indexed columns.

F.The secondary indexes are optimized for unique key look-ups.

A.The join buffer is used to process sorts when complex joins are being performed.

B.The value should be increased from the default if the query joins large rows without using an index.

C.The join buffer is global and can be changed only by restarting the server.

D.The value should be increased if the client performs several SELECToperations.

E.The join buffer is set per connection.

A.

B.

C.

D.

A.Each connection may have its own per-thread memory allocations.

B.Global memory resources are allocated at server startup.

C.Each thread allocates memory from a global pool.

D.Thread memory is pre-allocated up to thread_cache_size for performance.