A startup has been experimenting with DynamoDB in its new test environment.
The development team has discovered that some of the write operations have been overwriting existing items that have the specified primary key.
This has messed up their data, leading to data discrepancies.
Which DynamoDB write option should be selected to prevent this kind of overwriting? Conditional writes Batch writes Atomic Counters Use Scan operation.
Your web application reads and writes data to your DynamoDB table.
The table is provisioned with 400 Write Capacity Units (WCU’s) shared across 4 partitions.
One of the partitions receives 250 WCU/second while others receive much less. You receive the error 'ProvisionedThroughputExceededException'.
What is the likely cause of this error? You have a hot partition CloudWatch monitoring is lagging Configured IAM policy is wrong Write-capacity units (WCU’s) are applied across to all your DynamoDB tables and this needs reconfiguration.
A firm uses AWS DynamoDB to store information about people’s favorite sports teams and allow the information to be searchable from their home page.
There is a daily requirement that all 10 million records in the table should be deleted then re-loaded at 2:00 AM each night.
Which option is an efficient way to delete with minimal costs? Delete then re-create the table Scan and call DeleteItem Scan and call BatchDeleteItem Call PurgeTable.
As a Full-stack Web Developer, you are involved with every aspect of a company’s platform from development with PHP and JavaScript to the configuration of NoSQL databases with Amazon DynamoDB.
You are not concerned about your response receiving stale data from your database and need to perform 16 eventually consistent reads per second of 12 KB in size each.
How many read capacity units (RCUs) do you need? 24 12 192 48.
A development team uses the AWS SDK for Java to maintain an application that stores data in AWS DynamoDB.
The application makes use of Scan operations to return several items from a 25 GB table.
There is no possibility of creating indexes to retrieve these items predictably.
Developers are trying to get these specific rows from DynamoDB as fast as possible.
Which of the following options can be used to improve the performance of the Scan operation? Use parallel scans Use a ProjectionExpression Use a FilterExpression Use a Query.
You are implementing a banking application in which you need to update the Exchanges DynamoDB table and the AccountBalance DynamoDB table at the same time or not at all.
Which DynamoDB feature should you use? DynamoDB Transactions DynamoDB TTL DynamoDB Streams DynamoDB Indexes.
DynamoDB stores data as groups of attributes, known as items. Items are similar to rows or records in other database systems.
DynamoDB stores and retrieves each item based on the primary key value, which must be unique.
Items are distributed across 10-GB storage units, called partitions (physical storage internal to DynamoDB).
DynamoDB uses the partition key’s value as an input to an internal hash function.
The output from the hash function determines the partition in which the item is stored.
Each item’s location is determined by the hash value of its partition key. movie_id producer_name lead_actor_name movie_language.
A mobile game has a DynamoDB table named TutorialsDojoScores which keeps track of the users and their respective scores.
Each item in the table is identified by the FighterId attribute as its partition key and the FightTitle attribute as the sort key.
A developer needs to retrieve data from non-key attributes of the table named DojoTopScores and DojoDateTime attributes.
Which type of index should the developer add in the table to speed up queries on non-key attributes? Global Secondary Index Sparse Index Local Secondary Index Primary Index.
A developer is planning to add a global secondary index in a DynamoDB table.
This will allow the application to query a specific index that can span all of the data in the base table, across all partitions.
Which of the following should the developer consider when using this type of index? (Select TWO.) Queries on this index support eventual consistency only Queries or scans on this index consume capacity units from the index, not from the base table. Queries or scans on this index consume read capacity units from the base table. For each partition key value, the total size of all indexed items must be 10 GB or less. When you query this index, you can choose either eventual consistency or strong consistency.
A reporting application is hosted in Elastic Beanstalk and uses DynamoDB as its database. If a user requests for data, it scans the entire table and returns the requested data.
In the coming weeks, it is expected that the table will grow due to the surge of new users and requested reports.
Which of the following should be done as a preparation to improve the performance of the application with minimal cost? (Select TWO.) Reduce page size Use Query operations instead Increase page size Increase the Write Compute Unit (WCU) of the table Use DynamoDB Accelerator (DAX).
A software engineer is developing a serverless application which will use a DynamoDB database.
One of the requirements is that each write request should return the total number of write capacity units consumed, with subtotals for the table and any secondary indexes that were affected by the operation.
What should be done to accomplish this feature? Add the ReturnConsumedCapacity parameter with a value of INDEXES in every write request. Add the ReturnValues parameter with a value of INDEXES in every write request. Add the ReturnConsumedCapacity parameter with a value of TOTAL in every write request. Add the ReturnValues parameter with a value of TOTAL in every write request.
An online forum requires a new table in DynamoDB named Thread in which the partition key is ForumName and the sort key is Subject.
The following diagram shows how the items in the table would be organized:
For reporting purposes, the application needs to find all of the threads that have been posted in a particular forum within the last three months.
Which of the following is the MOST effective solution that you should implement? Add a local secondary index while creating the new Thread table. Use the Query operation to utilize the LastPostDateTime attribute as the sort key. Create a global secondary index and use the Query operation to utilize the LastPostDateTime attribute as the sort key. Configure the application to Query the entire Thread table and discard any posts that were not within the specified time frame. Configure the application to Scan the entire Thread table and discard any posts that were not within the specified time frame.
A company has a global multi-player game with a multi-master DynamoDB database topology which stores data in multiple AWS regions.
You were assigned to develop a real-time data analytics application which will track and store the recent changes on all the tables from various regions.
Only the new data of the recently updated item is needed to be tracked by your application.
Which of the following is the MOST suitable way to configure the data analytics application to detect and retrieve the updated database entries automatically? Enable DynamoDB Streams and set the value of StreamViewType to NEW_IMAGE. Use Kinesis Adapter in the application to consume streams from DynamoDB. Enable DynamoDB Streams and set the value of StreamViewType to NEW_IMAGE. Create a trigger in AWS Lambda to capture stream data and forward it to your application Enable DynamoDB Streams and set the value of StreamViewType to NEW_AND_OLD_IMAGE. Use Kinesis Adapter in the application to consume streams from DynamoDB. Enable DynamoDB Streams and set the value of StreamViewType to NEW_AND_OLD_IMAGE. Create a trigger in AWS Lambda to capture stream data and forward it to your application.
You have two users concurrently accessing a DynamoDB table and submitting updates.
If a user will modify a specific item in the table, she needs to make sure that the operation will not affect another user's attempt to modify the same item.
You have to ensure that your update operations will only succeed if the item attributes meet one or more expected conditions.
Which of the following DynamoDB features should you use in this scenario? Conditional writes Update Expressions Batch Operations Projection Expressions.
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