groupArrayMovingSum

Introduced in: v20.1.0

Calculates the moving sum of input values.

The function can take the window size as a parameter. If left unspecified, the function takes the window size equal to the number of rows in the column.

Syntax

groupArrayMovingSum(numbers_for_summing)
groupArrayMovingSum(window_size)(numbers_for_summing)

Parameters

window_size — Size of the calculation window. If left unspecified, the function takes the window size equal to the number of rows in the column. UInt64

Arguments

numbers_for_summing — Expression resulting in a numeric data type value. (U)Int* or Float* or Decimal

Returned value

Returns an array of the same size and type as the input data. Array

Examples

Usage example

CREATE TABLE t
(
    `int` UInt8,
    `float` Float32,
    `dec` Decimal32(2)
)
ENGINE = Memory;

INSERT INTO t VALUES (1, 1.1, 1.10), (2, 2.2, 2.20), (4, 4.4, 4.40), (7, 7.77, 7.77);

SELECT
    groupArrayMovingSum(int) AS I,
    groupArrayMovingSum(float) AS F,
    groupArrayMovingSum(dec) AS D
FROM t;

┌─I──────────┬─F───────────────────────────────────────────────────────────────────────────┬─D───────────────────┐
│ [1,3,7,14] │ [1.100000023841858,3.3000000715255737,7.700000166893005,15.470000147819519] │ [1.1,3.3,7.7,15.47] │
└────────────┴─────────────────────────────────────────────────────────────────────────────┴─────────────────────┘

With window size

SELECT
    groupArrayMovingSum(2)(int) AS I,
    groupArrayMovingSum(2)(float) AS F,
    groupArrayMovingSum(2)(dec) AS D
FROM t;

┌─I──────────┬─F────────────────────────────────────────────────────────────────────────────┬─D───────────────────┐
│ [1,3,6,11] │ [1.100000023841858,3.3000000715255737,6.6000001430511475,12.170000076293945] │ [1.1,3.3,6.6,12.17] │
└────────────┴──────────────────────────────────────────────────────────────────────────────┴─────────────────────┘