acg_questions Flashcards
What is a Dimension in CloudWatch?
A Dimension in CloudWatch is a filter used to specify a particular aspect of a metric. For example, you can use the InstanceId dimension to search for metrics related to a specific EC2 instance.
What is a Namespace in CloudWatch?
A Namespace in CloudWatch is a container for CloudWatch metrics. For example, EC2 uses the AWS/EC2 namespace. A namespace cannot be used for filtering.
What is Real-Time Streaming Data Processing?
Real-Time Streaming Data Processing typically involves processing large volumes of data in real-time or near-real-time, often using services like Amazon Kinesis.
What is the purpose of stack termination setting ‘Enable’ in CloudFormation?
Enabling stack termination prevents the accidental deletion of an entire CloudFormation stack.
What does ‘DeletionPolicy’ set to ‘Retain’ in a CloudFormation template do?
Setting ‘DeletionPolicy’ to ‘Retain’ in a CloudFormation template preserves resources if the stack is deleted, ensuring that specified resources are not deleted when the stack is deleted.
Where should passwords be passed in CloudFormation templates?
Passwords should be passed in the Parameters section of CloudFormation templates to ensure security and flexibility in managing sensitive information.
What does the DynamoDB GetItem operation do?
The GetItem operation in DynamoDB returns a set of attributes for the item with the given primary key. If there is no matching item, GetItem does not return any data and there will be no Item element in the response.
How can you limit the attributes returned in a DynamoDB GetItem operation?
You can use a ProjectionExpression to limit the attributes returned in a DynamoDB GetItem operation, but you cannot use a FilterExpression.
What are the requirements for performing DynamoDB Queries?
For DynamoDB Queries, you must provide the name of the partition key attribute and a single value for that attribute. Optionally, you can provide a sort key attribute and use a comparison operator to refine the search results.
What is the purpose of a filter expression in DynamoDB Queries?
A filter expression in DynamoDB Queries is applied after a Query finishes, but before the results are returned. It determines which items within the results should be returned to you, with all other results discarded.
What is the purpose of a scan operation in DynamoDB?
A Scan operation in Amazon DynamoDB reads every item in a table or a secondary index. By default, a Scan operation returns all of the data attributes for every item in the table or index.
What are Projection Expressions in DynamoDB?
Projection Expressions are used to specify the attributes that you want to retrieve from a DynamoDB table. They allow you to get only some, rather than all, of the attributes.
What is the difference between PutItem and UpdateItem in DynamoDB?
PutItem creates a new item or replaces an old item with a new one, while UpdateItem edits an existing item’s attributes or adds a new item to the table if it does not already exist.
What is the Lambda Basic Execution Role?
The Lambda Basic Execution Role is a role automatically created by Lambda, with permissions to upload logs to Amazon CloudWatch Logs. It can be changed to another role or permissions can be added to it.
What is the purpose of CodeDeploy’s appspec file?
CodeDeploy uses the appspec file to specify instructions for deploying applications to instances. It defines the deployment lifecycle, including pre-deployment and post-deployment actions.
