Microsoft Microsoft Certified: Azure Cosmos DB Developer Specialty DP-420 Questions & Answers

• Question 71:

  HOTSPOT

  You have a container named container1 in an Azure Cosmos DB Core (SQL) API account. The container1 container has 120 GB of data.

  The following is a sample of a document in container1.

  

  The orderIdproperty is used as the partition key.

  For each of the following statements, select Yes if the statement is true. Otherwise, select No.

  NOTE: Each correct selection is worth one point.

  Hot Area:

  

  Correct Answer:

  

  Box 1: Yes

  Records with different OrderIDs will match.

  Box 2: Yes

  Records with different OrderIDs will match.

  Box 3: No

  Only records with one specific OrderId will match

• Question 72:

  HOTSPOT

  You have a container in an Azure Cosmos DB Core (SQL) API account.

  You need to use the Azure Cosmos DB SDK to replace a document by using optimistic concurrency.

  What should you include in the code? To answer, select the appropriate options in the answer area.

  NOTE: Each correct selection is worth one point.

  Hot Area:

  

  Correct Answer:

  

  Box 1: ConsistencyLevel

  The ItemRequestOptions Class ConsistencyLevel property gets or sets the consistency level required for the request in the Azure Cosmos DB service.

  Azure Cosmos DB offers 5 different consistency levels. Strong, Bounded Staleness, Session, Consistent Prefix and Eventual - in order of strongest to weakest consistency.

  Box 2: _etag

  The ItemRequestOptions class helped us implement optimistic concurrency by specifying that we wanted the SDK to use the If-Match header to allow the server to decide whether a resource should be updated. The If-Match value is the ETag

  value to be checked against. If the ETag value matches the server ETag value, the resource is updated.

  Reference:

  https://docs.microsoft.com/en-us/dotnet/api/microsoft.azure.cosmos.itemrequestoptions

  https://cosmosdb.github.io/labs/dotnet/labs/10-concurrency-control.html

• Question 73:

  HOTSPOT

  You are creating a database in an Azure Cosmos DB Core (SQL) API account. The database will be used by an application that will provide users with the ability to share online posts. Users will also be able to submit comments on other

  users' posts.

  You need to store the data shown in the following table.

  

  The application has the following characteristics:

  1.

  Users can submit an unlimited number of posts.

  2.

  The average number of posts submitted by a user will be more than 1,000.

  3.

  Posts can have an unlimited number of comments from different users.

  4.

  The average number of comments per post will be 100, but many posts will exceed 1,000 comments.

  5.

  Users will be limited to having a maximum of 20 interests.

  For each of the following statements, select Yes if the statement is true. Otherwise, select No.

  NOTE: Each correct selection is worth one point.

  Hot Area:

  

  Correct Answer:

  

  Box 1: Yes

  Non-relational data increases write costs, but can decrease read costs.

  Box 2: Yes

  Non-relational data increases write costs, but can decrease read costs.

  Box 3: No

  Non-relational data increases write costs, but can decrease read costs.

• Question 74:

  HOTSPOT

  You have a database in an Azure Cosmos DB SQL API Core (SQL) account that is used for development.

  The database is modified once per day in a batch process.

  You need to ensure that you can restore the database if the last batch process fails. The solution must minimize costs.

  How should you configure the backup settings? To answer, select the appropriate options in the answer area.

  NOTE: Each correct selection is worth one point.

  Hot Area:

  

  Correct Answer:

  

• Question 75:

  HOTSPOT

  You have an Azure Cosmos DB Core (SQL) API account named account1.

  You have the Azure virtual networks and subnets shown in the following table.

  

  The vnet1 and vnet2 networks are connected by using a virtual network peer.

  The Firewall and virtual network settings for account1 are configured as shown in the exhibit.

  

  For each of the following statements, select Yes if the statement is true. Otherwise, select No.

  NOTE: Each correct selection is worth one point.

  Hot Area:

  

  Correct Answer:

  

  Box 1: Yes

  VM1 is on vnet1.subnet1 which has the Endpoint Status enabled.

  Box 2: No

  Only virtual network and their subnets added to Azure Cosmos account have access. Their peered VNets cannot access the account until the subnets within peered virtual networks are added to the account.

  Box 3: No

  Only virtual network and their subnets added to Azure Cosmos account have access.

  Reference:

  https://docs.microsoft.com/en-us/azure/cosmos-db/how-to-configure-vnet-service-endpoint

• Question 76:

  HOTSPOT

  You have an Azure Cosmos DB Core (SQL) API account used by an application named App1.

  You open the Insights pane for the account and see the following chart.

  

  Use the drop-down menus to select the answer choice that answers each question based on the information presented in the graphic.

  NOTE: Each correct selection is worth one point.

  Hot Area:

  

  Correct Answer:

  

  Box 1: incorrect connection URLs

  400 Bad Request: Returned when there is an error in the request URI, headers, or body. The response body will contain an error message explaining what the specific problem is.

  The HyperText Transfer Protocol (HTTP) 400 Bad Request response status code indicates that the server cannot or will not process the request due to something that is perceived to be a client error (for example, malformed request syntax,

  invalid request message framing, or deceptive request routing).

  Box 2: 6 thousand

  201 Created: Success on PUT or POST. Object created or updated successfully.

  Note:

  200 OK: Success on GET, PUT, or POST. Returned for a successful response.

  404 Not Found: Returned when a resource does not exist on the server. If you are managing or querying an index, check the syntax and verify the index name is specified correctly.

  Reference:

  https://docs.microsoft.com/en-us/rest/api/searchservice/http-status-codes

• Question 77:

  HOTSPOT

  You plan to deploy two Azure Cosmos DB Core (SQL) API accounts that will each contain a single database. The accounts will be configured as shown in the following table.

  

  How should you provision the containers within each account to minimize costs? To answer, select the appropriate options in the answer area.

  NOTE: Each correct selection is worth one point.

  Hot Area:

  

  Correct Answer:

  

  Box 1: Serverless capacity mode Azure Cosmos DB serverless best fits scenarios where you expect intermittent and unpredictable traffic with long idle times. Because provisioning capacity in such situations isn't required and may be cost-prohibitive, Azure Cosmos DB serverless should be considered in the following use-cases:

  1.

  Getting started with Azure Cosmos DB

  2.

  Running applications with bursty, intermittent traffic that is hard to forecast, or low (<10%) average-to-peak traffic ratio

  3.

  Developing, testing, prototyping and running in production new applications where the traffic pattern is unknown

  4.

  Integrating with serverless compute services like Azure Functions

  Box 2: Provisioned throughput capacity mode and autoscale throughput The use cases of autoscale include: Variable or unpredictable workloads: When your workloads have variable or unpredictable spikes in usage, autoscale helps by automatically scaling up and down based on usage. Examples include retail websites that have different traffic patterns depending on seasonality; IOT workloads that have spikes at various times during the day; line of business applications that see peak usage a few times a month or year, and more. With autoscale, you no longer need to manually provision for peak or average capacity.

  Reference: https://docs.microsoft.com/en-us/azure/cosmos-db/serverless https://docs.microsoft.com/en-us/azure/cosmos-db/provision-throughput-autoscale#use-cases-of-autoscale

• Question 78:

  HOTSPOT

  You have an Azure Cosmos DB Core (SQL) API account named account1.

  In account1, you run the following query in a container that contains 100GB of data.

  SELECT *

  FROM c

  WHERE LOWER(c.categoryid) = "hockey"

  You view the following metrics while performing the query.

  

  For each of the following statements, select Yes if the statement is true. Otherwise, select No.

  NOTE: Each correct selection is worth one point.

  Hot Area:

  

  Correct Answer:

  

  Box 1: No

  Each physical partition should have its own index, but since no index is used, the query is not cross-partition.

  Box 2: No

  Index utilization is 0% and Index Look up time is also zero.

  Box 3: Yes

  A partition key index will be created, and the query will perform across the partitions.

  Reference:

  https://docs.microsoft.com/en-us/azure/cosmos-db/sql/how-to-query-container

• Question 79:

  HOTSPOT

  You have the indexing policy shown in the following exhibit.

  

  Use the drop-down menus to select the answer choice that answers each question based on the information presented in the graphic.

  NOTE: Each correct selection is worth one point.

  Hot Area:

  

  Correct Answer:

  

  Box 1: ORDER BY c.name DESC, c.age DESC

  Queries that have an ORDER BY clause with two or more properties require a composite index.

  The following considerations are used when using composite indexes for queries with an ORDER BY clause with two or more properties:

  1.

  If the composite index paths do not match the sequence of the properties in the ORDER BY clause, then the composite index can't support the query.

  2.

  The order of composite index paths (ascending or descending) should also match the order in the ORDER BY clause.

  3.

  The composite index also supports an ORDER BY clause with the opposite order on all paths.

  Box 2: At the same time as the item creation Azure Cosmos DB supports two indexing modes:

  1.

  Consistent: The index is updated synchronously as you create, update or delete items. This means that the consistency of your read queries will be the consistency configured for the account.

  2.

  None: Indexing is disabled on the container.

  Reference: https://docs.microsoft.com/en-us/azure/cosmos-db/index-policy

• Question 80:

  HOTSPOT

  You have a container named container1 in an Azure Cosmos DB Core (SQL) API account.

  The following is a sample of a document in container1.

  {

  "studentId": "631282",

  "firstName": "James",

  "lastName": "Smith",

  "enrollmentYear": 1990,

  "isActivelyEnrolled": true,

  "address": {

  "street": "",

  "city": "",

  "stateProvince": "",

  "postal": "",

  }

  }

  The container1 container has the following indexing policy.

  {

  "indexingMode": "consistent",

  "includePaths": [

  {

  "path": "/*"

  },

  {

  "path": "/address/city/?"

  }

  ],

  "excludePaths": [

  {

  "path": "/address/*"

  },

  {

  "path": "/firstName/?"

  }

  ]

  }

  For each of the following statements, select Yes if the statement is true. Otherwise, select No.

  NOTE: Each correct selection is worth one point.

  Hot Area:

  

  Correct Answer:

  

  Box 1: Yes

  "path": "/*" is in includePaths.

  Include the root path to selectively exclude paths that don't need to be indexed. This is the recommended approach as it lets Azure Cosmos DB proactively index any new property that may be added to your model.

  Box 2: No

  "path": "/firstName/?" is in excludePaths.

  Box 3: Yes

  "path": "/address/city/?" is in includePaths

  Reference:

  https://docs.microsoft.com/en-us/azure/cosmos-db/index-policy