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TopCount

Returns the specified number of top-most rows in decreasing order of rank as specified by an expression.

Syntax

TopCount(<table expression>, <rank expression>, <count>)

Applies To

An expression that returns a table, such as a <table column reference>, or a function that returns a table.

Return Type

<table expression>

Remarks

The value that is supplied by the <rank expression> argument determines the decreasing order of rank for the rows that are supplied in the <table expression> argument, and the number of top-most rows that is specified in the <count> argument is returned.

For example, assume that the following Sub-SELECT statement returns the table below:

(SELECT [Product Name], $Probability AS [Probability] FROM Predict([Products Purchases], INCLUDE_STATISTICS))
Product name Probability

Apples

0.4

Kiwi fruit

0.1

Oranges

0.5

Lemons

0.2

The TopCount function can be used with the Sub-SELECT statement as follows:

TopCount((SELECT [Product Name], $Probability AS [Probability] FROM Predict([Products Purchases], INCLUDE_STATISTICS)), [Probability], 2)

This example yields the following results:

Product name Probability

Oranges

0.5

Apples

0.4

See Also

Reference

Data Mining Extensions (DMX) Function Reference
Functions (DMX)
Mapping Functions to Query Types (DMX)

Help and Information

Getting SQL Server 2005 Assistance