CUME_DIST

CUME_DIST calculates the cumulative distribution of a value in a group of values.

Syntax

CUME_DIST () OVER ( [ PARTITION BY expression [, ...] ]

 ORDER BY expression [ ASC | DESC ] [ NULLS { FIRST | LAST } [, ...] )

Remarks

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CUME_DIST can be rewritten using COUNT. For example:

CUME_DIST() OVER (partition_by_order_by)

This is equivalent to either of the following COUNT expressions:

COUNT (*) OVER ( partition_by_order_by RANGE UNBOUNDED PRECEDING )

COUNT (*) OVER ( partition_by_order_by RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING ) )

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The range of values returned by CUME_DIST is (0, 1]; that is, greater than zero, and less than or equal to 1.

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Tie values always evaluate to the same cumulative distribution value.

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PARTITION BY is optional.

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ORDER BY is required.

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The window clause is not allowed.