An ecommerce company is using Amazon DynamoDB as the backend for its order-processing application. The
steady increase in the number of orders is resulting in increased DynamoDB costs. Order verification and reporting perform many repeated GetItem functions that pull similar datasets, and this read activity is contributing to the increased costs. The company wants to control these costs without significant development efforts.
How should a Database Specialist address these requirements?
"Applications that are read-intensive, but are also cost-sensitive. With DynamoDB, you provision the number of reads per second that your application requires. If read activity increases, you can increase your tables' provisioned read throughput (at an additional cost). Or, you can offload the activity from your application to a DAX cluster, and reduce the number of read capacity units that you need to purchase otherwise."
A Database Specialist modified an existing parameter group currently associated with a production Amazon RDS for SQL Server Multi-AZ DB instance. The change is associated with a static parameter type, which controls the number of user connections allowed on the most critical RDS SQL Server DB instance for the company. This change has been approved for a specific maintenance window to help minimize the impact on users.
How should the Database Specialist apply the parameter group change for the DB instance?
A company has an application that uses an Amazon DynamoDB table to store user data. Every morning, a single-threaded process calls the DynamoDB API Scan operation to scan the entire table and generate a critical start-of-day report for management. A successful marketing campaign recently doubled the number of items in the table, and now the process takes too long to run and the report is not generated in time.
A database specialist needs to improve the performance of the process. The database specialist notes that, when the process is running, 15% of the table’s provisioned read capacity units (RCUs) are being used.
What should the database specialist do?
A company is going through a security audit. The audit team has identified cleartext master user password in the AWS CloudFormation templates for Amazon RDS for MySQL DB instances. The audit team has flagged this as a security risk to the database team.
What should a database specialist do to mitigate this risk?
A manufacturing company’s website uses an Amazon Aurora PostgreSQL DB cluster.
Which configurations will result in the LEAST application downtime during a failover? (Choose three.)
A company is using Amazon Aurora PostgreSQL for the backend of its application. The system users are complaining that the responses are slow. A database specialist has determined that the queries to Aurora take longer during peak times. With the Amazon RDS Performance Insights dashboard, the load in the chart for average active sessions is often above the line that denotes maximum CPU usage and the wait state shows that most wait events are IO:XactSync.
What should the company do to resolve these performance issues?
A company’s ecommerce website uses Amazon DynamoDB for purchase orders. Each order is made up of a Customer ID and an Order ID. The DynamoDB table uses the Customer ID as the partition key and the Order ID as the sort key.
To meet a new requirement, the company also wants the ability to query the table by using a third attribute named Invoice ID. Queries using the Invoice ID must be strongly consistent. A database specialist must provide this capability with optimal performance and minimal overhead.
What should the database administrator do to meet these requirements?
as Local secondary index can only be created while creating the Dynamodb table. and query needs to use third attribute on top of primary and sort key, so Local Secondary index has primary and sort key as well as the third attribute. Global secondary index can be created without primary and sort key
A company is deploying a solution in Amazon Aurora by migrating from an on-premises system. The IT department has established an AWS Direct Connect link from the company’s data center. The company’s Database Specialist has selected the option to require SSL/TLS for connectivity to prevent plaintext data from being set over the network. The migration appears to be working successfully, and the data can be queried from a desktop machine.
Two Data Analysts have been asked to query and validate the data in the new Aurora DB cluster. Both Analysts are unable to connect to Aurora. Their user names and passwords have been verified as valid and the Database Specialist can connect to the DB cluster using their accounts. The Database Specialist also verified that the security group configuration allows network from all corporate IP addresses.
What should the Database Specialist do to correct the Data Analysts’ inability to connect?
• To connect using SSL:
• Provide the SSLTrust certificate (can be downloaded from AWS)
• Provide SSL options when connecting to database
• Not using SSL on a DB that enforces SSL would result in error
A company is concerned about the cost of a large-scale, transactional application using Amazon DynamoDB that only needs to store data for 2 days before it is deleted. In looking at the tables, a Database Specialist notices that much of the data is months old, and goes back to when the application was first deployed.
What can the Database Specialist do to reduce the overall cost?
A financial institution uses AWS to host its online application. Amazon RDS for MySQL is used to host the application's database, which includes automatic backups.
The program has corrupted the database logically, resulting in the application being unresponsive. The exact moment the corruption occurred has been determined, and it occurred within the backup retention period.
How should a database professional restore a database to its previous state prior to corruption?
When you perform a restore operation to a point in time or from a DB Snapshot, a new DB Instance is created with a new endpoint (the old DB Instance can be deleted if so desired). This is done to enable you to create multiple DB Instances from a specific DB Snapshot or point in time."
Recently, a financial institution created a portfolio management service. The application's backend is powered by Amazon Aurora, which supports MySQL.
The firm demands a response time of five minutes and a response time of five minutes. A database professional must create a disaster recovery system that is both efficient and has a low replication latency.
How should the database professional tackle these requirements?
The Amazon CloudWatch metric for FreeLocalStorage on an Amazon Aurora MySQL DB instance shows that the amount of local storage is below 10 MB. A database engineer must increase the local storage available in the Aurora DB instance.
How should the database engineer meet this requirement?
Unlike for other DB engines, for Aurora DB instances this metric reports the amount of storage available to each DB instance. This value depends on the DB instance class (for pricing information, see the Amazon RDS product page). You can increase the amount of free storage space for an instance by choosing a larger DB instance class for your instance."
A bank intends to utilize Amazon RDS to host a MySQL database instance. The database should be able to handle high-volume read requests with extremely few repeated queries.
Which solution satisfies these criteria?
A Database Specialist is creating Amazon DynamoDB tables, Amazon CloudWatch alarms, and associated infrastructure for an Application team using a development AWS account. The team wants a deployment
method that will standardize the core solution components while managing environment-specific settings separately, and wants to minimize rework due to configuration errors.
Which process should the Database Specialist recommend to meet these requirements?
A company is using an Amazon Aurora PostgreSQL DB cluster with an xlarge primary instance master and two large Aurora Replicas for high availability and read-only workload scaling. A failover event occurs and application performance is poor for several minutes. During this time, application servers in all Availability Zones are healthy and responding normally.
What should the company do to eliminate this application performance issue?
"You can customize the order in which your Aurora Replicas are promoted to the primary instance after a failure by assigning each replica a priority. Priorities range from 0 for the first priority to 15 for the last priority. If the primary instance fails, Amazon RDS promotes the Aurora Replica with the better priority to the new primary instance. You can modify the priority of an Aurora Replica at any time. Modifying the priority doesn't trigger a failover. More than one Aurora Replica can share the same priority, resulting in promotion tiers. If two or more Aurora Replicas share the same priority, then Amazon RDS promotes the replica that is largest in size. If two or more Aurora Replicas share the same priority and size, then Amazon RDS promotes an arbitrary replica in the same promotion tier. "
Amazon Aurora with PostgreSQL compatibility now supports cluster cache management, providing a faster path to full performance if there's a failover. With cluster cache management, you designate a specific reader DB instance in your Aurora PostgreSQL cluster as the failover target. Cluster cache management keeps the data in the designated reader's cache synchronized with the data in the read-write instance's cache. If a failover occurs, the designated reader is promoted to be the new read-write instance, and workloads benefit immediately from the data in its cache.
A company wants to migrate its on-premises MySQL databases to Amazon RDS for MySQL. To comply with the company’s security policy, all databases must be encrypted at rest. RDS DB instance snapshots must also be shared across various accounts to provision testing and staging environments.
Which solution meets these requirements?
A database expert is responsible for building a highly available online transaction processing (OLTP) solution that makes use of Amazon RDS for MySQL production databases. Disaster recovery criteria include a cross-regional deployment and an RPO and RTO of 5 and 30 minutes, respectively.
What should the database professional do to ensure that the database meets the criteria for high availability and disaster recovery?
A business is operating an on-premises application that is divided into three tiers: web, application, and MySQL database. The database is predominantly accessed during business hours, with occasional bursts of activity throughout the day. As part of the company's shift to AWS, a database expert wants to increase the availability and minimize the cost of the MySQL database tier.
Which MySQL database choice satisfies these criteria?
Amazon Aurora Serverless v1 is a simple, cost-effective option for infrequent, intermittent, or unpredictable workloads. https://aws.amazon.com/rds/aurora/serverless/
An electric utility company wants to store power plant sensor data in an Amazon DynamoDB table. The utility company has over 100 power plants and each power plant has over 200 sensors that send data every 2 seconds. The sensor data includes time with milliseconds precision, a value, and a fault attribute if the sensor is malfunctioning. Power plants are identified by a globally unique identifier. Sensors are identified by a unique identifier within each power plant. A database specialist needs to design the table to support an efficient method of finding all faulty sensors within a given power plant.
Which schema should the database specialist use when creating the DynamoDB table to achieve the fastest query time when looking for faulty sensors?
Plant id as partition key and Sensor id as a sort key. Fault can be identified quickly using the local secondary index and associated plant and sensor can be identified easily.
A company is looking to move an on-premises IBM Db2 database running AIX on an IBM POWER7 server. Due to escalating support and maintenance costs, the company is exploring the option of moving the workload to an Amazon Aurora PostgreSQL DB cluster.
What is the quickest way for the company to gather data on the migration compatibility?
A business's production databases are housed on a 3 TB Amazon Aurora MySQL DB cluster. The database cluster is installed in the region us-east-1. For disaster recovery (DR) requirements, the company's database expert needs to fast deploy the DB cluster in another AWS Region to handle the production load with an RTO of less than two hours.
Which approach is the MOST OPERATIONALLY EFFECTIVE in meeting these requirements?
RTO is 2 hours. With 3 TB database, cross-region replica is a better option
A marketing company is using Amazon DocumentDB and requires that database audit logs be enabled. A Database Specialist needs to configure monitoring so that all data definition language (DDL) statements performed are visible to the Administrator. The Database Specialist has set the audit_logs parameter to enabled in the cluster parameter group.
What should the Database Specialist do to automatically collect the database logs for the Administrator?
Auditing Amazon DocumentDB Events
With Amazon DocumentDB (with MongoDB compatibility), you can audit events that were performed in your cluster. Examples of logged events include successful and failed authentication attempts, dropping a collection in a database, or creating an index. By default, auditing is disabled on Amazon DocumentDB and requires that you opt in to use this feature.
When auditing is enabled, Amazon DocumentDB records Data Definition Language (DDL), authentication, authorization, and user management events to Amazon CloudWatch Logs. When auditing is enabled, Amazon DocumentDB exports your cluster’s auditing records (JSON documents) to Amazon CloudWatch Logs. You can use Amazon CloudWatch Logs to analyze, monitor, and archive your Amazon DocumentDB auditing events.
An online shopping company has a large inflow of shopping requests daily. As a result, there is a consistent load on the company’s Amazon RDS database. A database specialist needs to ensure the database is up and running at all times. The database specialist wants an automatic notification system for issues that may cause database downtime or for configuration changes made to the database.
What should the database specialist do to achieve this? (Choose two.)
A software development company is using Amazon Aurora MySQL DB clusters for several use cases, including development and reporting. These use cases place unpredictable and varying demands on the Aurora DB clusters, and can cause momentary spikes in latency. System users run ad-hoc queries sporadically throughout the week. Cost is a primary concern for the company, and a solution that does not require significant rework is needed.
Which solution meets these requirements?