transform function

Transforms elements in an array in expr using the function func.

Syntax 

transform(expr, func)

Arguments

  • expr: An ARRAY expression.

  • func: A lambda function.

Returns

An ARRAY of the type of the lambda function’s result.

The lambda function must have 1 or 2 parameters. The first parameter represents the element, the optional second parameter represents the index of the element.

The lambda function produces a new value for each element in the array.

Examples 

> SELECT transform(array(1, 2, 3), x -> x + 1);
 [2,3,4]
> SELECT transform(array(1, 2, 3), (x, i) -> x + i);
 [1,3,5]