This documentation is related to an older version of Firebolt. For the most current documentation, see Firebolt documentation.

REDUCE

Applies an aggregate function on the elements of the array and returns its result. The name of the aggregation function is passed as a string in single quotes - for example: 'max', 'sum'.

Syntax

REDUCE(<function>, <array>)

Parameters

Parameter	Description	Supported input types
`<function>`	The name of an aggregation function in the form of a quoted string.	Any aggregation function
`<array>`	The array to aggregate.	`ARRAY`

Return Types

Same as the element data type of the input array

Examples

SELECT
	REDUCE('max', [ 1, 2, 3, 6 ]) AS levels;

Returns: 6

When using aggregation functions that take a constant as a parameter, the parameter should be specified after the function name in parentheses. This example below uses REDUCE with the APPROX_PERCENTILE function, which requires a percentile as a parameter.

SELECT
	REDUCE('approx_percentile(0.3)', [ 1, 2, 3, 4, 5, 6 ]) AS levels;

Returns: 2.5