Oracle 1Z0-888 Quiz 5 Topic 12 Questions 21-25

Question: 1

Which three tasks are handled by the optimizer?

ADecide which indexes to use.

BRewrite the WHERE clause.

CParse the query.

DChange the order in which the tables are joined.

EValidate the query.

FExecute the query.

GVerify that the user is allowed to execute the query.

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Question: 2

After analysis on the slow query log on a high-end OLTP service, the table identified in the slow queries is:

q2_1Z0-888

What are the two most likely reasons for the slowness given this output?

ADate should be a TIMESTAMP field for better performance.

BThe User field is too long for most names.

CThe engine type is not appropriate to the application use.

DUsing default values for DATETIME causes table scans.

ENo indexes are defined.

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Question: 3

A crucial database, 'db_prod', just disappeared from your production MySQL instance.

In reviewing the available MySQL logs (General, Audit, or Slow) and your own application-level logs, you

identified this command from a customer facing application:

SELECT id FROM users WHERE login='payback!';DROP DATABASE db_prod;'

Which three methods could have been used to prevent this SQL injection attack from happening?

Awriting your client code to properly escape all user input

Bgiving limited privileges to accounts used by application servers to interact with their backing databases

Cusing SSL/TLS on your outward facing web servers (https://) to encrypt all user sessions

Dusing a hashing or encryption method to secure all user passwords in your MySQL tables

Eremoving any remaining anonymous accounts from your MySQL instance

Fvalidating all user input before sending it to the database server

Gchanging all passwords for the MySQL account 'root'@'%' immediately after losing an employee who knew the current password

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Question: 4

Which three statements correctly describe MySQL InnoDB Cluster?

AThe cluster can be operated in multimaster mode with conflict detection for DML statements.

BAll MySQL client programs and connectors can be used for executing queries.

CIt provides fully synchronous replication between the nodes.

DThere is support for automatic failover when one node fails.

EThe data is automatically shared between the nodes.

FEach query will be executed in parallel across the nodes.

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Question: 5

Force Majeure is a catastrophic failure on a major level of the database operation. Regular backups are key to helping avoid data loss in such situations.

Which two other steps can help avoid data loss in a major catastrophe?

AImplement a failover strategy to another geographic location.

BCreate a master-master pair for each service.

CHave a second data centre in a different region or country.

DKeep software updated to the latest version.

EUse RAID 10 storage for datA.

FUse on-site network-attached storage to separate service from datA.

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Oracle 1Z0-888 Quiz:5 Topic:12 Questions:21-25