Cubing — Head function (MDX)

The Head function returns a specified number of elements from the beginning of a set.

Returns: A set.

Syntax


>>-Head--(--SetExpression--+----------------------+--)---------><
                           '-,--NumericExpression-'

Parameters

SetExpression: Specifies an expression that returns a set.
NumericExpression: Specifies a numeric expression that specifies the number of elements within a set that you want returned.
If you do not specify a numeric expression, the default value is 1. If you specify a number that is greater than the number of elements in a set, the complete original set is returned. If you specify a numeric expression that is less than 1, an empty set is returned.

Description

Use the Head function to return a specific number of elements starting from the beginning of a set. The order of elements that are returned is maintained within the new set.

Example

In this example, you want to see which stores are the most profitable. The following query uses the Head function to return the profit amount of the three stores that have the largest profit amounts.

Query

SELECT {[Price Analysis].[Measures].[Profit Amount]} 
          ON AXIS(0), 
       {Head(Order(Descendants([Price Analysis].[Store].[All Stores], -1, LEAVES),
                    [Price Analysis].[Measures].[Profit Amount], BDESC), 3)} 
          ON AXIS(1)
FROM [Price Analysis]

Result

Store	Profit amount
ValueTrend Store 1199	84813.24
ValueTrend Store 116	81950.42
ValueTrend Store 1095	81673.1

Related functions

You can use the Tail function to get a specified number of elements from the end of a set.

You can use the Subset function to get a specified number of elements from any part of a set.