groupArrayMovingSum

Calculates the moving sum of input values.

groupArrayMovingSum(numbers_for_summing)
groupArrayMovingSum(window_size)(numbers_for_summing)

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.

Arguments

numbers_for_summing — Expression resulting in a numeric data type value.
window_size — Size of the calculation window.

Returned values

Array of the same size and type as the input data.

Example

The sample table:

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

┌─int─┬─float─┬──dec─┐
│   1 │   1.1 │ 1.10 │
│   2 │   2.2 │ 2.20 │
│   4 │   4.4 │ 4.40 │
│   7 │  7.77 │ 7.77 │
└─────┴───────┴──────┘

The queries:

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

┌─I──────────┬─F───────────────────────────────┬─D──────────────────────┐
│ [1,3,7,14] │ [1.1,3.3000002,7.7000003,15.47] │ [1.10,3.30,7.70,15.47] │
└────────────┴─────────────────────────────────┴────────────────────────┘

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] │ [1.1,3.3000002,6.6000004,12.17] │ [1.10,3.30,6.60,12.17] │
└────────────┴─────────────────────────────────┴────────────────────────┘