MB-820 Microsoft Dynamics 365 Business Central Developer Free Practice Exam Questions (2025 Updated)

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.

Table Structure in Business Central: When creating entities such as "non-conformity" entities in Business Central, you use document tables to represent entities that have a header and line structure. In this case, the non-conformity entity has:

A header with common information (Non-conformity Number, Date, Vendor No., etc.).

One or more lines representing the detailed information for each non-conforming item.

Document Table Usage:

Document Table: A document table is the correct table type for scenarios where you have a header (with general information like vendor details) and lines (with detailed, item-specific information).

Document tables are typically used for entities such as Sales Orders, Purchase Orders, or any other transactional data where you have both header and line information.

Supplemental Table (Option C):

Supplemental tables are usually used to add supplementary information to existing data in Business Central. In this case, we need to store detailed line information, which is a core part of the entity rather than supplementary data, so a supplemental table would not be appropriate here.

Document History Table (Option A):

Document history tables are used to track changes and historical data for entities but are not suitable for the main introduction of the entity and its lines. This option is also not appropriate.

Reference Documentation:

Introduction to Business Central Tables

Document Tables in Business Central

API Publishing for Extensions:

In Business Central, when creating custom APIs like RoomsAPI, it is important to ensure that they are automatically published during the installation or upgrade of the extension.

To achieve this, you can include a codeunit of type Install in the extension that explicitly publishes the custom API (RoomsAPI) as a web service. This ensures that it is available for use immediately after the extension is deployed without requiring manual intervention.

Codeunit Type:

A codeunit of type Install runs when the extension is installed or upgraded. This type of codeunit can be used to perform setup tasks such as publishing web services or APIs like RoomsAPI.

Why Not Other Options?

Option A (default API configuration): This would not automatically publish the RoomsAPI. Default APIs do not cover custom APIs.

Option B (enable APIs for the environment): Enabling APIs in Business Central allows the standard APIs to be used, but custom APIs still need to be manually published.

Option C (publish via Web Services page): This would work but requires manual intervention to publish RoomsAPI, which does not fulfill the requirement of automatic publishing during installation.

Reference Documentation:

Publishing APIs in Extensions

Codeunit Types in Business Central

field(3; "Receipt No."; Code[20])

{

DataClassification = CustomerContent;

TableRelation = "Purch. Rcpt. Header"."No." where ("Buy-from Vendor No." = field("Vendor No."));

}

Field Declaration:

The field(3; "Receipt No."; Code[20]) part defines the field in the table with ID 3 and type Code with a length of 20. This field will hold the receipt number.

DataClassification:

CustomerContent is selected for the DataClassification property, which categorizes the data for privacy and compliance management. This aligns with Business Central's recommendations for handling sensitive data in customer-related tables.

TableRelation Property:

The TableRelation property links the "Receipt No." field to another table, which in this case is the "Purch. Rcpt. Header" table. This ensures that only valid receipt numbers from the Purchase Receipt Header table can be selected or entered in this field.

Relation Filter:

The filter condition is applied using the where clause. It ensures that the Receipt No. is only from the Purchase Receipt Header records where the "Buy-from Vendor No." matches the "Vendor No." of the current record.

The condition field("Vendor No.") is selected from the drop-down as shown in the image. This links the vendor information in the non-conformity table to the receipt in the Purchase Receipt Header table.

By linking the "Vendor No." fields, you ensure that only receipt numbers from the correct vendor are available, which improves data consistency and reduces errors during data entry.

References to AL Language:

The TableRelation property is frequently used to create references between tables in Business Central. In this case, the correct relationship between the "Purch. Rcpt. Header" and the Non-conformity table is established using the TableRelation and filter.

Reference Documentation:

AL TableRelation Property

AL Field Syntax

codeunit 52102 "POS API Management"

{

Access = Public;

Permissions = TableData "POS Information" = rwdx;

trigger OnRun()

begin

readAPI();

end;

procedure readAPI()

begin

// Your code here to read from the POS API

end;

}

https://api.businesscentral.dynamics.com/v2.6/myTenant/myEnvironment/api/alpine/integration/rooms

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

Handler methods are used in tests to simulate user interactions, such as responding to dialogs, confirmation messages, or option selections. Since you need to simulate the user interaction of selecting a posting option (Ship, Invoice, Ship & Invoice), a Handler method would be the appropriate choice for capturing this kind of user input.

Normal attribute and Test attribute are used for marking methods for test execution, but they do not simulate user interaction, making Handler method the correct answer.

For more details, see the Microsoft Docs on Test Codeunits and Handler Methods.

To assign the indirect permissions for the Boxes table to the codeunit, use the following code blocks in sequence:

TableData

"Boxes" =

Permissions

RIM

Assigning permissions:

In Business Central, to assign permissions within a codeunit, you need to specify the table that the permissions apply to, followed by the type of permission. The sequence starts by indicating that we are defining table data permissions (TableData). Then, we specify the table in question ("Boxes" =). After that, we state that we are setting permissions (Permissions). Finally, we assign the RIM permissions, which stands for Read, Insert, and Modify permissions. The Indirect permission allows the codeunit to read, insert, and modify records in the Boxes table indirectly, meaning these operations can be performed by the codeunit when it is called by a user who has direct permissions for these operations.

To enable debugging in an extension and allow the source code to be viewed, the allowDebugging property should be specified in the app.json file (C). The app.json file serves as the manifest for an AL project in Microsoft Dynamics 365 Business Central, defining the project's properties, dependencies, and features. By setting the allowDebugging property to true in this file, developers enable the debugging of the extension's source code, facilitating troubleshooting and development. This is essential for analyzing the behavior of the extension and identifying issues during the development process.

In the context of cleaning up sandbox environments for a company where data needs to be cleared each time an extension is published, the schemaUpdateMode property in the launch.json file should be set to Recreate (D). Setting this property to Recreate ensures that every time the extension is published, the existing tables and data are dropped, and then the tables are recreated based on the current extension's schema. This mode is particularly useful in development and testing environments where you need a clean slate for testing each version of the extension without the remnants of previous data affecting the outcomes. It's important to use this setting cautiously, as it results in the loss of all existing data in the tables defined by the extension, which is suitable for a sandbox environment but not for production environments.

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.

Codeunit "Discount Mgmt." compiles successfully. = NO

VariantLine in line 17 must be changed to Line and the DiscountAmount removed for the codeunit to compile. = NO

The DiscountIsValid method must be defined in the interface for the code to compile. = YES

The codeunit "Discount Mgmt." will not compile successfully as is because the DiscountIsValid method is not defined in the "IDiscount Calculation" interface, yet it is being declared in the codeunit which implements this interface. AL requires that all procedures in the codeunit that implements an interface must be defined in the interface itself.

The VariantLine in line 17 does not need to be changed to Line, nor does the DiscountAmount need to be removed for the codeunit to compile. These are valid declarations in AL and they are correctly implemented in the codeunit. The Variant data type in AL is used to handle various data types and DiscountAmount is a valid return type for a procedure.

For the code to compile successfully, the DiscountIsValid method must be included in the interface because AL enforces that any codeunit implementing an interface must implement all the methods defined in that interface.

Using InherentPermissions in an event subscriber with the specified syntax could potentially resolve the permission issues related to MyTable, provided that the permissions specified (in this case, 'R' for Read) align with the minimum necessary for the users to perform their tasks. This approach allows the app to grant permissions dynamically based on the context of the event subscriber, which in this case is involved with inserting data into MyTable. By granting Read permission at the event level, it ensures that users have the necessary permissions to interact with MyTable in the context of the operations facilitated by the event subscriber, without needing to alter existing permission sets or grant broader permissions than necessary. This solution adheres to the principle of least privilege by ensuring that permissions are granted only within the narrow scope needed for specific operations, thereby potentially resolving the reported user issues in a secure and controlled manner.

A: In Business Central, wizard pages are created using the NavigatePage type because it allows step-by-step navigation, which is perfect for wizard-like user experiences.

B: The group control organizes the content for each step in the guide, and it’s essential to add these controls to the layout's Content area for each step of the wizard.

C: Worksheet is used for pages designed to handle larger datasets, not for wizard or step-by-step flows.

D: Repeater controls are used for displaying multiple records, not for guiding users through steps, so it’s incorrect for this scenario.

For more information, you can refer to Assisted Setup in Business Central.