How to update Nth Element of an array

Question

Is it possible to update/replace the nth element of an array

input =[1,2,3,4]

Update 3rd element from 3 to 5

Output=[1,2,5,4]]

Answer 1

In ADF, self-referencing variables is not supported. So, use a temporary variable first and then reassign that temporary variable value to required one.

If you only want to do it in ADF and not in dataflow, follow the below approach.

I have created two array variables named x with values [1,2,3,4] and temp.

I have created two parameters for nth element and updated value.

X value at start:

I have used the below expression to get the updated array.

@createArray(take(variables('x'),sub(pipeline().parameters.nth,1)),pipeline().parameters.value,skip(variables('x'),pipeline().parameters.nth))

This will give output like below.

To get the array in required format, use the below expression and assign the value to required variable.

@json(concat('[',replace(replace(string(variables('temp')), '[', ''),']',''),']'))

Result: