Microsoft MB-820 Microsoft Dynamics 365 Business Central Developer Exam Practice Test

To create an HTTP GET request that connects to an external REST service in a Business Central online environment, the solution to use is the HttpClient data type variable (E). The HttpClient data type in AL language is designed for sending HTTP requests and receiving HTTP responses from a resource identified by a URI. This makes it the ideal choice for interfacing with external REST services, as it provides the necessary methods and properties to configure and execute HTTP GET requests, handle the responses, and process the data returned by the REST service. This approach is more direct and flexible compared to using specific codeunits like "Web Request Helper" (B) or "Http Web Request Mgt" (D), which might not provide the same level of control or specificity needed for RESTful interactions.

Assigning a SUPER permission set to all users would indeed resolve the permission errors and access issues reported by the users, as it grants full permissions across all objects and data in Business Central. However, this approach contradicts the principle of least privilege, which advocates for providing only the minimum levels of access necessary for users to perform their jobs. The SUPER permission set would excessively elevate user privileges, potentially leading to security risks and unintended modifications to critical data. Therefore, while assigning the SUPER permission set might technically resolve the immediate issues, it does not meet the goal of adhering to the principle of least privilege and is not a recommended solution.

To round up a decimal variable to four decimal places in Microsoft Dynamics 365 Business Central, you should use the Round function with specific parameters. The correct formula is Result := Round(AmountLCY, 0.0001, '=') (B). This function rounds the AmountLCY variable to the nearest value based on the second parameter, which is 0.0001 in this case, representing four decimal places. The third parameter, '=', specifies that the function should round to the nearest value, which effectively rounds up the value when it's halfway between two possible rounded values. This approach ensures that the AmountLCY variable is accurately rounded to four decimal places, which is essential for financial calculations and reporting to maintain precision.

In a single-tenant deployment architecture of Business Central on-premises, the following characteristics describe how the data is stored and how the Business Central Server is configured:

The application and the business data are stored in the same database (B): In a single-tenant architecture, each tenant (which typically corresponds to a single customer) has its own dedicated database. This database contains both the application objects (such as pages, reports, codeunits, etc.) and the business data (such as customer, vendor, and transaction records). This setup ensures that each tenant's data is isolated and can be managed independently.

The application and business data are stored in separate databases (D): While (B) is a characteristic of a single-tenant deployment, it's important to clarify that in some configurations, the application objects can be stored in a separate database from the business data. This approach can be used for easier maintenance and upgrades of the application code without affecting the business data. However, each tenant still has its own set of databases, maintaining the single-tenancy model.

The other options provided do not accurately describe a single-tenant architecture:

Each customer has their own Business Central Server (A): This statement might be misleading. In a single-tenant deployment, while each customer has their own database, they do not necessarily have their own Business Central Server instance. Multiple databases (tenants) can be hosted on a single server instance, although they are not shared across customers.

Multiple customers share a single Business Central Server (C) and Multiple customers share multiple Business Central Server instances (E): These options describe a multi-tenant architecture rather than a single-tenant one. In a multi-tenant setup, multiple customers (tenants) can share the same server instance and even the same application database, with data isolation ensured at the application level.

For the data integrity requirements, the table field properties to use are:

To establish lookups into other records, use the TableRelation property.

To validate if a record exists in a destination record, use the ValidateTableRelation property.

In Business Central, when creating tables to hold data, maintaining data integrity is crucial:

TableRelation Property:This property is used to create a relationship between the field in one table and a field in another table, which is typically used for lookups. When you set the TableRelation property on a field, it allows users to select from a list of values that exist in the related table.

ValidateTableRelation Property:This property is used to ensure that the value entered in a field matches one of the values in a related table. If a user tries to enter a value that doesn't exist in the related table, an error will occur.

Include all records from TableA Header even if no matching record value exists in the linked TableA Line: LeftOuterJoin

Include only matched records from TableB Header: InnerJoin

In SQL and similarly in Business Central when defining table relationships in query objects, the type of join determines how records from one table are combined with records from another table. Here's what each join type means in the context of the company's requirements:

LeftOuterJoin:

A LeftOuterJoin includes all records from the 'left' table (TableA Header) and the matched records from the 'right' table (TableA Line). If there is no match, the result is NULL on the side of the 'right' table. This is why it fits the requirement to include all records from TableA Header even if there is no matching record in TableA Line.

InnerJoin:

An InnerJoin includes records when there is at least one match in both tables. So, it will only include records from TableB Header where a corresponding match is found in TableB Line. If there is no match, the records from TableB Header will not appear in the result set. This aligns with the requirement to include only matched records from TableB Header.

By using these join types, the company can ensure that their dataset includes the appropriate records from the document tables and document history tables according to their specified requirements.

To prevent a caption from being translated in an extension for Microsoft Dynamics 365 Business Central, you should add the Locked = true parameter to the Caption (C). This parameter explicitly marks the caption as locked for translation, ensuring that it remains unchanged across different language versions of the extension. This approach is useful for specific terms, brand names, or other elements within the application that should remain consistent regardless of the user's language settings. Unlike the other options, which involve manual manipulation of the translation file or properties, setting Locked = true directly in the AL code provides a clear, maintainable, and error-proof method to exclude specific captions from the translation process.

To create the Approver field in the Item table using an AL extension, perform the following actions in sequence:

Create an enum object named Approver and include all options.

Create a table extension object for an Item table with an Approver field of enum type named Approver in the fields section.

Create a page extension object that extends the Item Card object. Add the field to the fields section.

Build and extend tables:To add a new field to an existing table in Business Central using AL extension, you need to define an enumeration (enum) with the possible values for the new field. Then, you create a table extension object where you add the new field and specify its type as the enum you created. This adds the field to the Item table. Finally, you modify the user interface to display the new field by creating a page extension for the Item Card page and adding the new field to it.

You are working on an on-premises Business Central instance and unable to download symbols for a new AL project. The current configuration in launch.json does not allow you to download symbols, and you need to make corrections.

Key Points in the Scenario:

Instance name is TEST.

Developer services port is 7149.

Windows authentication is being used.

Correct Answers:

A. Change the server Instance parameter to TEST.

The serverInstance parameter must match the name of the Business Central instance, which is TEST in this scenario. You need to modify this to reflect the correct instance name.

B. Add the port: 7149 parameter.

Since the developer services are using port 7149, you need to specify this in the launch.json file by adding the port parameter with the value 7149.

Incorrect Options:

C. Change the name parameter to TEST: The name parameter is just a label and does not affect downloading symbols, so changing this won't help.

D. Change the authentication parameter to UserPassword: The authentication method is already set to Windows, which is valid for this scenario. Changing it to UserPassword is unnecessary unless specified by the system.

E. Check which server the instance is installed on and replace http://localhost with the correct IP address: Since the server is on the same machine as Visual Studio Code (as specified), localhost is correct.

In the context provided by the case study, when calling an API action from a mobile application, the correct format for a POST request to an action in Business Central typically involves specifying the entity (/issues), the ID of the entity (88122e0e-5796-ec11-bb87-000d3a392eb5), and the action to be called (/Copy). The action name should match the exact name as defined in the AL code, which is case-sensitive.

Option A is incorrect because it uses a non-standard format for the action call.

Option B uses the PATCH method, which is generally used for update operations, not for calling actions.

Option C is correct as it uses the POST method, which is appropriate for calling actions, and correctly specifies the entity, ID, and action name.

Option D is incorrect because the action name /copy is in lowercase, while AL is case-sensitive, and it should match the case exactly as defined in the code.

Option E incorrectly adds 'MicrosoftNAV' before the action name, which is not standard for calling actions in Business Central APIs.

Hence, the correct action to use when calling the Issue API action from the mobile application is given in Option C.

To correctly write the code to call the subcontractor's REST API, you would need to set the Authorization header with the base64 encoded username and password for basic authentication. The code segment indicates the use of the Base64Convert codeunit to convert the username and password to base64 format, which is then prefixed with "Basic " to form the proper Authorization header value.

The correct method to add the Authorization header to the RequestHeaders would be:

RequestHeaders.Add('Authorization', 'Basic ' + Base64Convert.ToBase64(Username + ':' + Password));

And the correct method to set the httpContent with the body of the request would be:

httpContent.WriteFrom(Body);

These are the necessary steps to form a well-structured HTTP request for basic authentication and to include the body of the request in the API call.

The task is to identify unwanted incoming web service calls during the last seven days. To do this, we need to look at KQL (Kusto Query Language) queries that would filter out web service calls based on the timestamp (to ensure the calls are within the last seven days) and by certain characteristics that would indicate they are unwanted, such as the wrong type of protocol (SOAP in this case, as Contoso Ltd. plans to dismiss using it).

Looking at the options:

Option A: This query selects all traces where the timestamp is within the last 7 days and where the custom dimension has a value of 'RT0008', and where the category is either 'ODataV4', 'ODataV3', or 'Api'. This query would show all API calls except SOAP, so it does not directly answer the question about unwanted calls.

Option B: This query filters for traces with a timestamp within the last 7 days, where 'RT0008' is present, and specifically looks for the category 'SOAP'. This query is correct because it directly targets SOAP calls, which are the unwanted calls according to Contoso Ltd.'s plans.

Option C: Similar to option B, this query filters for traces within the last 7 days and looks for 'RT0008' but uses the equality operator for the category 'SOAP'. This would also correctly return the unwanted SOAP calls.

Option D: This query also filters for traces within the last 7 days, but it excludes the 'ODataV4' category, which doesn't necessarily target the unwanted SOAP calls.

Option E: This query selects traces where the timestamp is within the last 7 days and the custom dimension has 'RT0008'. However, it filters out categories 'ODataV4' and 'Api', which does not directly help in identifying the unwanted SOAP calls.

Therefore, the queries that should be used to determine if there are unwanted incoming web service calls (SOAP calls) in the tenant during the last seven days are Options B and C. These queries are specific to identifying SOAP protocol usage, which is what Contoso Ltd. considers unwanted.

Code Segment Analysis:

The AL code is trying to read JSON data from a response and process it to extract subcontracting order numbers. It uses JsonToken, JsonObject, and JsonArray to work with the JSON data.

JToken.ReadFrom(Data): This line reads the incoming JSON data and converts it into a token. It processes the full JSON body so you can start working with it.

JToken.SelectToken("results"): This line selects the part of the JSON containing the results array. The key "results" is where the JSON response data is expected to be found.

JsonArray: Once the results are extracted, they are stored as an array, and each element in the array (which is expected to contain subcontracting order numbers) is processed.

SubcontractingOrderNo: The extracted order_no from the JSON is stored in this variable.

Breakdown of Steps:

JToken.ReadFrom(Data): This step reads the entire JSON response.

JToken.SelectToken("results"): This step selects the results array from the JSON response.

JArray.AsArray(): This step converts the selected results token into a JSON array that can be iterated over.

GetValueAsText(JToken, 'order_no'): This step retrieves the order_no from each element in the array.

Correct Code Completion:

JToken.ReadFrom(Data): This is the correct method to read the incoming JSON response, as it will convert the string into a JsonToken that can be further processed.

JToken.SelectToken("results"): This is the correct method to extract the results array from the token. This method looks for the key "results" in the JSON and retrieves the relevant array.

Final Code Segment:

al

Copy code

procedure ReadJsonData(Data: text)

var

JToken: JsonToken;

JObject: JsonObject;

JArray: JsonArray;

SubcontractingOrderNo: Code[20];

begin

if Data = '' then

exit;

JToken := JToken.ReadFrom(Data); // Step 1: Read the JSON response data.

JToken := JToken.SelectToken('results'); // Step 2: Select the "results" array.

JArray := JToken.AsArray(); // Convert the token into a JSON array.

foreach JToken in JArray do begin

SubcontractingOrderNo := GetValueAsText(JToken, 'order_no'); // Retrieve the order number.

end;

end;

JToken.ReadFrom(Data): This reads the raw JSON data string and converts it into a JSON token that can be processed.

JToken.SelectToken("results"): This extracts the results array from the JSON data.

JArray.AsArray(): Converts the token into an array so we can iterate over it.

GetValueAsText(JToken, 'order_no'): Extracts the order_no value from each item in the array.

In the context of Microsoft Dynamics 365 Business Central, an extension may not appear in the tenant for several reasons, particularly after an upgrade to a new major version.

Option A suggests that the extension was published as a DEV extension, which typically would not cause it to disappear after an upgrade because DEV extensions are intended for development and testing within sandbox environments.

Option B indicates that the extension was not compatible with the new version within 60 days of the first notification. This is a likely reason because Microsoft enforces compatibility rules, and extensions that are not made compatible within the specified timeframe might be removed or disabled.

Option C refers to the extension being published as a PTE (Per-Tenant Extension) and mentions the Platform parameter not being updated. This could cause issues, but not specifically the disappearance of the extension after an upgrade.

Option D expands on Option C by adding that both the Platform and Runtime parameters were not updated in the application file. This is a critical aspect because if these parameters are not correctly set to indicate compatibility with the new version of Business Central, the extension could be disabled or removed.

Option E is similar to Option B but mentions a 90-day period. This option does not align with standard Business Central practices for version compatibility requirements.

Therefore, the two possible reasons for the disappearance of the extension in the tenant after an upgrade are that the extension was not compatible with the new version within the required timeframe (Option B) and that the extension was published as a PTE without the Platform and Runtime parameters being updated (Option D).

 Verbosity::Critical: This ensures that the telemetry logs the failure as a critical event.

 DataClassification::CustomerContent: This helps classify the error as related to customer data.

 TelemetryScope::All: This ensures that the error is visible across all relevant telemetry scopes, making it easier to monitor the issue in real-time.

 Upgrade codeunit trigger: OnValidateUpgradePerDatabase

Since the question specifies that you are handling data upgrades, and you need to use validation before upgrading at the database level, the correct choice is OnValidateUpgradePerDatabase. This method ensures that the upgrade process is validated before applying to the entire database, making it more efficient when data affects multiple companies or structures.

 DataTransfer method to use: CopyRows

CopyRows is the appropriate method when you are handling large data transfers between tables, especially in an upgrade scenario where you are migrating or transferring data from one table to another. It copies entire rows of data and is optimal for bulk data operations during upgrades.

Here is the most logical sequence of actions for implementing the Issue Management module in Business Central and exposing the PostIssue method:

Correct Order:

Create a codeunit named "Issue Management Impl." and set the value of Access property to Internal.

This is the first step because Issue Management Impl. is the implementation layer where the actual business logic resides, and setting it to Internal ensures that it is only accessible from within the module, following best practices in encapsulation.

Create a local procedure named PostIssueImpl in the "Issue Management Impl." codeunit.

This step adds the actual PostIssueImpl method, which contains the core logic of posting an issue.

Create a codeunit named "Issue Management" and set the value of Access property to Public.

After defining the implementation logic, you need to create a public-facing Issue Management codeunit to expose the service externally.

Create a PostIssue procedure in the "Issue Management" codeunit, and in it call the PostIssueImpl method.

Lastly, expose the PostIssue method in the Issue Management codeunit, which will internally call the PostIssueImpl method, completing the chain.

Read Scale-Out:

Read scale-out is a feature in Business Central that allows you to improve performance by distributing read-only queries (such as the ones from the ticketAPI) across multiple read replicas in the cloud database. This reduces the load on the primary database and helps improve the response time for read-intensive operations, like analyzing POS data through the ticketAPI.

Data Access Intent - ReadOnly:

When enabling read scale-out, you can configure the DataAccessIntent property of APIs to be ReadOnly. This directs the system to use read replicas to handle read-only queries, which enhances performance by offloading such queries from the primary database.

Why Not Other Options?

Option A (ODataReadonlyGetEnabled): This parameter is unrelated to read scale-out and primarily affects OData services behavior, not API performance tuning.

Option B (AccessByPermission): Setting the permission to Read does not directly affect the performance. It only controls access based on user permissions.

Option D (DataAccessIntent ReadOnly): While setting this property to ReadOnly helps in read-only operations, enabling read scale-out (option C) ensures the underlying infrastructure is optimized to handle such read operations, which is the fundamental action required.

Reference Documentation:

Read Scale-Out in Business Central

Data Access Intent in AL

For the Install codeunit required for the extension used for installing or updating the Housekeeping app, you should use the following data type and declaration:

Data type for information: ModuleInfo

Start of the declaration of the method or procedure to perform the tasks: local procedure

In AL language, which is used for developing extensions in Business Central, an Install codeunit is a special type of codeunit that is used to handle installation or upgrade logic for an extension.

ModuleInfo is a data type that contains information about the current extension, such as its version. It is typically used within the OnInstallAppPerCompany or OnUpgradePerCompany triggers of an Install codeunit to determine if the app is being installed for the first time or upgraded.

A local procedure within an Install codeunit is a method that is only accessible within the codeunit itself. It is not visible to other objects or extensions. This is suitable for tasks that are internal to the installation process and should not be exposed globally.

These selections align with the requirements of handling installation and update procedures in a controlled and encapsulated manner within Business Central extensions.

In Business Central, fields in tables are assigned specific data types that determine the kind of data they can store. For the Non-conformity table mentioned in the case study, the following data types should be used:

Date for the Non-Conformity Date field: This is because the Non-conformity Date field is required to store only the date when the non-conformity was recorded. The Date data type is appropriate for storing dates without times.

Code for the Non-Conformity Number field: The Non-conformity Number field is described to use alphanumeric values with a format that includes "NC" and the year, like "NC24-001". In Business Central, the Code data type is used for fields that store alphanumeric keys. It is a text field with a limited length, which makes it suitable for number series that contain letters and numbers.

Other options are not suitable:

A. Integer for the Non-conformity Number field: This would not be appropriate because the Non-conformity Number includes alphanumeric characters and not just integers.

B. DateTime for the Non-Conformity Date field: This is not correct because there is no requirement to store the time alongside the date.

C. Char for the Non-Conformity Number field: Char data type is not typically used in Business Central for number series or identifiers. The Code data type is preferred for this purpose.

Instructions to use for Incident Date and Status fields:

The correct instruction is "Incident Date" := Workdate(); "Status" := Status::Open;. This ensures that when a new record is created, the Incident Date is set to the current work date, and the Status field is initialized to 'Open'. This is essential for ensuring that the incident data is always timestamped and correctly marked upon creation.

Trigger to introduce the function:

The correct trigger is Trigger OnModify. This trigger ensures that when a record is modified, such as when an update to the status is made (e.g., from Open to Closed), the necessary logic will be executed to handle the update of fields like Incident Date and Status.

Step-by-Step References:

Workdate Function in AL

Triggers in AL

For the requirements provided, the appropriate page types should be selected as follows:

Display relevant insights in the Housekeeping Role Center: HeadlinePart

Display the additional information for the Room table: FactBox

Configure the first installation: StandardDialog

Comprehensive Detailed ExplanationIn the context of Microsoft Dynamics 365 Business Central, page types are crucial for determining how information is presented to the user.

HeadlinePart: This page type is designed to display key data and insights in a concise and visually appealing manner, often used in Role Centers to highlight important information. It is suitable for the Housekeeping Role Center to display relevant insights.

FactBox: This page type is used to display supplementary information related to a selected record in the main part of the page. It's often used to show additional details about a record in a list, card, or document page. In this scenario, it is suitable for showing additional information about a specific Room when viewing the Room table.

StandardDialog: This is a page type that provides a modal dialog for user interaction, commonly used for setup wizards, confirmations, and input forms that require user action before proceeding. This is appropriate for configuring the first installation, where a step-by-step guided interaction is necessary.