Alibaba ACA-Developer Exam Practice Test Instant Access

Question 1

A developer is making the ModifyDDInstanceSpec API call to change the specifications of an RDS instance, but the operation fails. Why could this be? (Number of correct answers: 3)

AThe instance is in the running state

BNo instance type (specification) was included in the request parameters

CThe instance has a backup task being executed

DThe targeted RDS instance is a disaster recovery instance

Answer : A, B, C

Question 2

Assume that a company uses ApsaraDB for PolarDB. The company commonly queries users based on their basic information, including: addresses, company names, and ID numbers. In this scenario, what is the best practice for creating a database index (or indexes)?

ACreate a b-tree index on each column to be searched.

BCreate a hash index on each column to be searched.

CCreate a gin index for multiple fields.

DCreate a gist index for multiple fields.

Answer : A

Question 3

Which of the following options is correct, regarding Object ACL in Alibaba Cloud's Object Storage Service (OSS)?

AObject ACL is an object-level (not bucket level) permission control mechanism. There are currently three levels of access rights: private, public-read, and public-read-write.

B'Private' indicates that an object is a private resource, that is, only the owner of the object has read and write permissions on the object, and other users can read but have no permission to modify or delete the object.

CIf the permissions of an object are not set, the permissions of the object are inherited from the bucket.

DYou can set the ACL associated with an object by examining the X-OSS-Object-ACL header in the HEAD request, when making the PutObjectACL API call.

Answer : A

Question 4

Which of the following is NOT a feature of Alibaba Cloud's Cassandra database service?

ACenterless distributed architecture

BSupports both narrow and wide tables, providing flexible schema functions

CCluster storage, strong expansion of read and write capabilities

DEnterprise-level capabilities such as disaster tolerance, backup and recovery, security, and monitoring across data centers

Answer : B

Question 5

A Developer is creating a Function Compute function. This function requires around 1 GB of temporary storage for files while executing. These files will not be needed after the function is completed for a fixed period. How can this developer MOST efficiently handle the temporary files?

AStore the files in Cloud Disk and delete the files when Function Compute function call completes.

BCopy the files to NFS and delete the files when the Function Compute function call completes.

CStore the files in the /tmp directory on a temporary ECS instance, and delete the files at when the Function Compute function call completes.

DCopy the files to an OSS bucket with a lifecycle policy configured to delete the files automatically.

Answer : C

Question 6

CloudMonitor's "Event Monitoring" feature provides you with event reporting, query, and alarm functions, Score 2 so that you can collect metrics on your running Alibaba Cloud systems, and receive alerts when something goes wrong. Which of these is NOT a correct description of the monitoring event types supported by CloudMonitor?

AFor ECS, CloudMonitor supports the collection and reporting of important ECS operating system level events, such as application crashes.

BFor Object Storage Service (OSS), CloudMonitor supports the collection and reporting of bucket upstream and downstream bandwidth which exceeds the flow control threshold or the user-selected reporting threshold.

CFor Server Load Balancer (SLB), CloudMonitor supports the collection and reporting of HTTPS certificate expiration events, for certificates installed on SLB.

DFor E-MapReduce, CloudMonitor supports the collection and reporting of service component status, cluster creation failure, and timeout events.

Answer : C

Question 7

When you use SQL statements to access tables in a database without an index configured, a full table scan will be performed. If a table contains a large amount of data, this kind of scan will access a large amount of data and consume a lot of the database's resources. Which of the following options are best practices when creating database indexes? (Number of correct answers: 3)

AAdd an index to a field that is frequently queried but does not frequently perform add, delete, or modify operations.

BApplies indices to fields that contain many records.

Ctable should not contain more than 6 indexed fields.

DApply indexing to fields of fixed length (preferably not long fields).

EAdhere to the rightmost prefix principle when using composite indexes.

Answer : A, B, D

Alibaba ACA-Developer ACA Developer Exam Practice Test