Defining a report dataset

You use a report object in the AL Language development environment to define the data model, or dataset, of a report. The dataset determines the data that is extracted or calculated from the Dynamics 365 Business Central database tables that can be used in a report. For more information, see Report Object.

Using tables in a dataset definition

You build the report dataset from data items and columns. A data item is a table. A column can be:

  • A field in a table

  • A variable

  • An expression

  • A text constant

Typically, data items and columns correspond to fields in a table. When the report is run, each data item is iterated for all records in the underlying table. Filters are applied and the dataset is created. When a report is based on more than one table, you must set relations between the data items so that you can retrieve and organize the data.

You can also extend a dataset from an existing report, to add more columns for example. For more information, see Report Extension Object.

Formatting field values in report datasets

It's often useful to format data in the report dataset to reduce the complexity of the report layout. For example, if a decimal field in a table has precision of five digits, the same level of precision might not be needed in the report. Or maybe you want to format dates or currencies in a different way in the report as they appear on the page in Business Central.

For more information, see Formatting field values in report datasets.

How to include field captions in report datasets

For texts that are present as captions on table fields in dataset columns, use the IncludeCaption property to include them in the dataset. For more information, see IncludeCaption property.

For more information about the use of labels in reports, see Report labels.

Using a query in a dataset definition

Instead of building the report dataset directly from tables, you can also use a query object. To achieve this, you must

  • Add a global variable that points to the query object
  • Use an Integer in the data item definition
  • Add OnPreDataItem and OnAfterGetRecord triggers

See an example of how to do this in the next section.

Snippet support

Typing the shortcut treport creates the basic layout for a report object when using the AL Language extension for Microsoft Dynamics 365 Business Central in Visual Studio Code.

Tip

Use Ctrl+Space to trigger IntelliSense and get assistance on code completion, parameter info, quick info, and member lists.

Testing the dataset

Tip

From the Business Central client, you can export report results as raw data to a Microsoft Excel file. The file contains all columns of the dataset, but without the layout applied. Use the file to help validate that the report returns the expected data, and to ensure that the report layout controls match the dataset value types. To export a report dataset to Excel, run the report and select the Send to > Microsoft Excel Document (data only) on the request page. For more information, see Working with Reports - Send to Excel.

Example: Joining tables to define a report dataset

The following example adds the Customer table as the data item and the CustomerName and CompanyName as fields of a column to the report. It then adds a secondary dataitem with data from the Cust. Ledger Entry table and joins the two.

dataitem(Customer; Customer)
{
    // For each field that you want to display you add a column control.
    
    column(No_Customer; "No.")
    {
        // Include the caption of the "No." field in the dataset of the report.
        IncludeCaption = true;
    }
    column(Name_Customer; Name)
    {
        IncludeCaption = true;
    }
    column(Phone_Customer; "Phone No.")
    {
        IncludeCaption = true;
    }
    column(Address_Customer; Address)
    {
        IncludeCaption = true;
    }
    column(EMail_Customer; "E-Mail")
    {
        IncludeCaption = true;
    }

    // If your dataset joins multiple tables, add secondary dataitems and link them
    dataitem(CustLedger; "Cust. Ledger Entry")
    {
        // Set a filter on the child data item, **CustLedgerEntry** to select only the records where the 
        // value of `Customer."No."` field and the `"Customer Ledger Entry"."Customer No."` field matches.
        DataItemLink = "Customer No." = field("No.");
        column(EntryNo_CustLedgerEntry; "Entry No.")
        {
            IncludeCaption = true;
        }
        column(CustomerNo_CustLedgerEntry; "Customer No.")
        {
            IncludeCaption = true;
        }
        column(PostingDate_CustLedgerEntry; "Posting Date")
        {
            IncludeCaption = true;
        }
        column(DocumentType_CustLedgerEntry; "Document Type")
        {
            IncludeCaption = true;
        }
        column(DocumentNo_CustLedgerEntry; "Document No.")
        {
            IncludeCaption = true;
        }
    }
}

Example: Define a report dataset with multiple top-level dataitems

The following example adds the Cust. Ledger Entry table as a top-level data item. It then add dimension data as a second top-level data item.

// Example of how to have two top-level dataitems in a report dataset.
dataset
{
    dataitem(CustLedger; "Cust. Ledger Entry")
    {
        column(EntryNo_CustLedgerEntry; "Entry No.")
        {
            IncludeCaption = true;
        }
        column(CustomerNo_CustLedgerEntry; "Customer No.")
        {
            IncludeCaption = true;
        }
        column(PostingDate_CustLedgerEntry; "Posting Date")
        {
            IncludeCaption = true;
        }
        column(DocumentType_CustLedgerEntry; "Document Type")
        {
            IncludeCaption = true;
        }
        column(DocumentNo_CustLedgerEntry; "Document No.")
        {
            IncludeCaption = true;
        }
        column(GlobalDim1Code_CustLedgerEntry; "Global Dimension 1 Code")
        {
            IncludeCaption = true;
        }
        column(GlobalDim2Code_CustLedgerEntry; "Global Dimension 2 Code")
        {
            IncludeCaption = true;
        }
    }
    dataitem(Dimensions; "Dimension Set Entry")
    {
        column(EntryNo_CustLedgerEntry; "Dimension Code")
        {
            IncludeCaption = true;
        }
        column(EntryNo_CustLedgerEntry; "Dimension Value Code")
        {
            IncludeCaption = true;
        }
        column(EntryNo_CustLedgerEntry; "Dimension Value ID")
        {
            IncludeCaption = true;
        }
    }
}

Example: Using a query to define a report dataset

Let's imagine that you have created the query object CustomerQuery that joins the customer data with data from some other table. The following example shows how you can use that query as the data source for a report dataset.

// Example of how to use a query as the data source for a report dataset.
dataset
{
    dataitem(Integer; Integer)
    {
        column(CustomerName; MyQuery.CustomerName)
        {
        }
        column(SomeFieldFromAnotherTable; MyQuery.SomeFieldFromAnotherTable)
        {
        }
        
        trigger OnPreDataItem()
        begin
            MyQuery.Open();
        end;

        trigger OnAfterGetRecord()
        begin
            if not MyQuery.Read() then
                CurrReport.Break();
        end;
    }
}

var 
    MyQuery: Query "CustomerQuery";

Report limit - maximum number of rows

The Business Central platform has built-in limits to protect the stability of the system from a single report consuming too many resources. For example, there's a limit on the maximum number of rows that can be processed in a report.

For more information on report limits, see Report limits.

See Also

IncludeCaption property
Report Object
Report Extension Object
Reports Overview
Report Design Overview