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Query.TopNumberOfRows([Integer]) Method

Version: Available or changed with runtime version 1.0.

Specifies the maximum number of rows to include in the resulting data set of a query.

Syntax

[CurrentRows := ]  Query.TopNumberOfRows([NewRows: Integer])

Note

This method can be invoked using property access syntax.

Parameters

Query
 Type: Query
An instance of the Query data type.

[Optional] NewRows
 Type: Integer
The number of rows to include in the resulting data set. If you do not set the NewRows parameter, then the resulting data set will include all rows. If you set the value to 0, then there is no limit and all rows of the data set are returned.

Return Value

[Optional] CurrentRows
 Type: Integer
Gets the current maximum number of rows included in the resulting data set

Remarks

You use the TopNumberOfRows method to limit the resulting dataset to the first set of rows that are generated for the query. For example, you can include only the first 10 or first 100 rows in the resulting dataset. The TopNumberOfRows method is useful for key performance indicators such as the top number of customers or sales.

You can also specify the number of rows to include in the dataset by setting the TopNumberOfRows Property. The TopNumberOfRows method will overwrite the TopNumberOfRows property setting.

Example

This code example demonstrates how to use the TopNumberOfRows method on a query to return the top 10 customer sales orders based on the quantity of items.

The following query object links table 18 Customer and table 37 Sales Line and uses the TopNumberOfRows property to get top 5 customer sales orders based on the quantity of items.

query 50123 "Customer_Sales_Quantity"
{
    QueryType = Normal;
    // Sets the resultS to include the top 5 the results in descending order
    TopNumberOfRows = 5;
    OrderBy = descending(Qty);

    elements
    {
        dataitem(C; Customer)
        {
            column(Customer_Number; "No.")
            {
            }

            column(Customer_Name; Name)
            {
            }

            dataitem(SL; "Sales Line")
            {
                DataItemLink = "Sell-to Customer No." = c."No.";
                SqlJoinType = InnerJoin;

                column(Qty; Quantity)
                {
                }
            }
        }
    }
}

The following codeunit runs the query, saves it as a CSV file, and displays a message that states the number of rows that are returned in the resulting dataset.

codeunit 50100 MyQueryTop10
{
    trigger OnRun()
    begin

        // Overwrites the TopNumberOfRows property and returns the first 10 rows in the dataset.  
        //MyQuery.TopNumberOfRows(10);
        // Opens the query.  
        MyQuery.Open;
        // Reads each row of the dataset and counts the number of rows.  
        while MyQuery.Read do begin
            Counter += 1;
        end;
        // Saves the dataset as a CSV file.  
        MyQuery.SaveAsCsv('c:\temp\CustomerSales.csv');
        // Displays a message that shows the number of rows.  
        Message(Text000, counter);

    end;

    var
        MyQuery: Query "Customer_Sales_Quantity";
        Counter: Integer;
        Text000: Label 'count %1.';
}

Query Data Type
Query Object
Linking and Joining Data Items
Aggregating Data in Query Objects
Filtering Data in Query Objects
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