Applies a function to each element of an array and returns a new array of results.
Quick example: select transform(array(1, 2, 3), x -> x + 1) returns [2, 3, 4].
Syntax
array<R> transform(array<T> <a>, function<T, R> <func>)Parameters
| Parameter | Required | Description |
|---|---|---|
a | Yes | The input array. T in array<T> is the element data type, which can be any supported data type. |
func | Yes | A built-in function, user-defined function (UDF), or expression applied to each element of a. The input type must match the element type T of a. R is the return type, which determines the element type of the output array. |
Return value
An array of type array<R>, where R is the return type of func.
Examples
Basic numeric transformation
-- Returns [2, 3, 4]
select transform(array(1, 2, 3), x -> x + 1);Note
The -> operator is the Lambda arrow operator. For syntax details and advanced usage, see Lambda functions.
Related functions
TRANSFORM is a complex type function. For other functions that process ARRAY, MAP, STRUCT, and JSON data, see Complex type functions.