A.variables_by_thread

B.global_variables

C.user_variables_by_thread

D.session_variables

A.It takes more than 8 milliseconds to sort the rows.

B.The query returns exactly 125 rows.

C.The optimizer estimates that 51 rows in the country table have Continent = 'Asia'.

D.The country table is accessed as the first table, and then joined to the city table.

E.35 rows from the city table are included in the result.

A.Start mysqld or mysqld_safe using different option files for each instance.

B.Use resource groups to lock different instances on separate CPUs.

C.Run mysqld with --datadir defined for each instance.

D.Use system tools to lock each instance to its own CPU.

E.Run MySQL Server docker containers.

F.Use systemd with different settings for each instance.

A.They allow for point-in-time recovery of the data.

B.Binary logs are relatively small, and therefore, excellent for long-term storage and disaster recovery.

C.Multiple binary logs can be applied in parallel for faster data restoration.

D.Multiple binary logs can be used to restore data.

E.Binary logs can always be used to unapply unwanted schema changes.

A.You must revoke all privileges from r_role1 and r_role2 before dropping the roles.

B.You must revoke r_role1 and r_role2 from all users and other roles before dropping the roles.

C.It fails if any of the roles is specified in the mandatory_roles variable.

D.Existing connections can continue to use the roles' privileges until they reconnect.

E.It fails if you do not have the ADMIN OPTION of the roles r_role1 and r_role2.

F.It fails if at least one of the roles does not exist.