cume_dist()

Returns the cumulative distribution, that is (number of partition rows preceding or peers with current row) / (total partition rows). The value thus ranges from 1/N to 1.

Signature

cume_dist () → double precision

Examples

SELECT product, cume_dist() OVER (ORDER BY amount) FROM orders;

 product  |      cume_dist      
----------+---------------------
 cable    | 0.16666666666666666
 mouse    |  0.3333333333333333
 keyboard |                 0.5
 keyboard |  0.6666666666666666
 monitor  |  0.8333333333333334
 monitor  |                   1
(6 rows)

Run against PostgreSQL 18.6 on 2026-09-13. This is the output we got, not the documentation’s.

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