ARRAY_COUNT

Counts the number of elements in an array for which function(array[i]) evaluates to TRUE, if a function is provided. If <function> is not provided, counts the number of elements in the array that evaluate to TRUE, equivalent to using x -> x. To count the elements in an array without any conditions, use the ARRAY_LENGTH function instead.

Syntax

ARRAY_COUNT(<function>, <array>)

Parameters

Parameter	Description	Supported input types
<function>	Optional. A Lambda function used to check elements in the array. If <function> is not provided, x -> x is used.	Any Lambda function returning BOOLEAN
<array>	An array of elements	Any ARRAY type if <function> is provided, else ARRAY(BOOLEAN)

Return Type

INTEGER

Examples

The example below searches through the array for any elements that are greater than 3. Only one number that matches this criteria is found, so the function returns 1

SELECT
	ARRAY_COUNT(x -> x > 3, [ 1, 2, 3, 9, NULL ]) AS levels;

Returns: 1

In this example below, there is no <function> provided in the ARRAY_COUNT function. This means the function will count all of the elements in the array that evaluate to TRUE. Below, this is the case for all values except FALSE and null:

SELECT
	ARRAY_COUNT([TRUE, FALSE, 2::BOOLEAN, 3 is not null, null is null, null]) AS levels;

Returns: 4