DP-420 Online Practice Questions and Answers

Correct Answer: B

Correct Answer: B

Correct Answer: B

Based on the characteristics of the application and the provided document structure, the most suitable partition key value for coll1 in the given scenario would be the customerId, Option B. The application frequently creates new orders by different customers and customers often view their past order history. Using customerId as the partition key would ensure that all orders associated with a particular customer are stored in the same partition. This enables efficient querying of past order history for a specific customer and reduces cross-partition queries, resulting in lower costs and improved performance. a partition key is a JSON property (or path) within your documents that is used by Azure Cosmos DB to distribute data among multiple partitions3. A partition key should have a high cardinality, which means it should have many distinct values, such as hundreds or thousands1. A partition key should also align with the most common query patterns of your application, so that you can efficiently retrieve data by using the partition key value1. Based on these criteria, one possible partition key that you could use for coll1 is B:customerId.

This partition key has the following advantages: It has a high cardinality, as each customer will have a unique ID3. It aligns with the query patterns of the application, as customers will often view their past order history3. It minimizes costs, as it reduces the number of cross-partition queries and optimizes the storage and throughput utilization1. This partition key also has some limitations, such as: It may not be optimal for scenarios where orders need to be queried independently from customers or aggregated by date or other criteria3. It may result in hot partitions or throttling if some customers create orders more frequently than others or have more data than others1. It may not support transactions across multiple customers, as transactions are scoped to a single logical partition2. Depending on your specific use case and requirements, you may need to adjust this partition key or choose a different one. For example, you could use a synthetic partition key that concatenates multiple properties of an item2, or you could use a partition key with a random or pre-calculated suffix to distribute the workload more evenly2.

Correct Answer: A

According to the Azure Cosmos DB documentation12, the change feed is a persistent record of changes to a container in the order they occur. The change feed outputs the sorted list of documents that were changed in the order in which

they were modified.

The Azure function that has a trigger on the change feed receives all the properties of the updated items2. The change feed does not include the original items or only the changed properties. The change feed also includes some system-

defined properties such as _ts (the last modified timestamp) and _lsn (the logical sequence number)3.

Therefore, the correct answer is "all the properties of the updated items"

Correct Answer: A

The indexing policy has an includedPaths array that contains only one path:

/product/brand/ . This means that only the properties under /product/brand will be indexed.

The symbol indicates that only scalar values will be indexed, not arrays or objects1.

The excludedPaths array contains a single path: /* .

This means that all other properties will be excluded from indexing.

The * symbol indicates a wildcard that matches any property name1.

Therefore, the paths /product/category , /product/[ ]/category , and /product/brand/tailspin will not be indexed.

Correct Answer: A

The solution is incorrect because there is no "isTom" parameter in the Azure Cosmos DB SDK. The correct parameter is "isTombstone".

Correct Answer: B

The disableLocalAuth property is a boolean flag that indicates whether local authentication methods such as primary/secondary keys are disabled for the Azure Cosmos DB account. Setting this property to true improves security by ensuring that Azure Cosmos DB accounts exclusively require Azure Active Directory identities for authentication1.

Correct Answer: B

Azure Monitor is a service that provides comprehensive monitoring for Azure resources, including Azure Cosmos DB. You can use Azure Monitor to collect, analyze, and alert on metrics and logs from your Azure Cosmos DB account. You can create alerts for Azure Cosmos DB using Azure Monitor based on the metrics, activity log events, or Log Analytics logs on your account1. For your scenario, if you want to receive an alert when requests that target the database exceed the available request units per second (RU/s), you should use the Document Quota metric. This metric measures the percentage of RU/s consumed by your account or container. You can create an alert rule on this metric from the Azure portal by following these steps2: In the Azure portal, select the Azure Cosmos DB account you want to monitor. Under the Monitoring section of the sidebar, select Alerts, and then select New alert rule. In the Create alert rule pane, fill out the Scope section by selecting your subscription name and resource type (Azure Cosmos DB accounts). In the Condition section, select Add condition and choose Document Quota from the list of signals. In the Configure signal logic pane, specify the threshold value and operator for your alert condition. For example, you can choose Greater than or equal to 90 as the threshold value and operator to receive an alert when your RU/s consumption reaches 90% or more of your provisioned throughput. In the Alert rule details section, specify a name and description for your alert rule. In the Actions section, select Add action group and choose how you want to receive notifications for your alert. For example, you can choose Email/SMS/Push/Voice as an action type and enter your email address or phone number as a receiver. Review your alert rule settings and select Create alert rule to save it.

Correct Answer: ABG

To Configure customer-managed keys for your Azure Cosmos account with Azure Key Vault:

Add an access policy to your Azure Key Vault instance:

1.

From the Azure portal, go to the Azure Key Vault instance that you plan to use to host your encryption keys. Select Access Policies from the left menu:

2.

Select + Add Access Policy.

3.

Under the Key permissions drop-down menu, select Get, Unwrap Key, and Wrap Key permissions:

Reference: https://docs.microsoft.com/en-us/azure/cosmos-db/how-to-setup-cmk

Correct Answer: B

Instead configure an Azure Monitor alert to trigger the function.

You can set up alerts from the Azure Cosmos DB pane or the Azure Monitor service in the Azure portal.

Reference:

https://docs.microsoft.com/en-us/azure/cosmos-db/create-alerts

Correct Answer: C

C: When triggers are registered, you can specify the operations that it can run with.

F: When executing, pre-triggers are passed in the RequestOptions object by specifying PreTriggerInclude and then passing the name of the trigger in a List object.

Reference: https://docs.microsoft.com/en-us/azure/cosmos-db/sql/how-to-use-stored-procedures-triggers-udfs

Correct Answer: B

Instead create an Azure function that uses Azure Cosmos DB Core (SQL) API change feed as a trigger and Azure event hub as the output.

The Azure Cosmos DB change feed is a mechanism to get a continuous and incremental feed of records from an Azure Cosmos container as those records are being created or modified. Change feed support works by listening to container for any changes. It then outputs the sorted list of documents that were changed in the order in which they were modified.

Reference: https://docs.microsoft.com/en-us/azure/cosmos-db/sql/changefeed-ecommerce-solution

Correct Answer: D

Explanation:

Time to live for containers and items

The time to live value is set in seconds, and it is interpreted as a delta from the time that an item was last modified. You can set time to live on a container or an item within the container:

Time to Live on a container (set using DefaultTimeToLive):

If missing (or set to null), items are not expired automatically.

If present and the value is set to "-1", it is equal to infinity, and items don't expire by default.

If present and the value is set to some non-zero number "n" – items will expire "n" seconds after their last modified time.

Reference:

https://learn.microsoft.com/en-us/azure/cosmos-db/nosql/time-to-live

Correct Answer: D

Reference: https://learn.microsoft.com/en-us/azure/cosmos-db/consistency-levels

Correct Answer: D