Neo4j: substraction between arrays with string elements

Question

I have the two following arrays:

 x=[red,blue,green,yellow,black,white,pink,orange,brown]
 y=[blue,white,pink]

How could I have the following output using Cypher?

 z=[red,,green,yellow,black,,,orange,brown]

I need to have an array with the same size of the array x and the elements in the same order but when there are common elements with the array y, I need to have blank elemnts.

Answer 1

You can use list comprehension.

For example, this query:

WITH
  ["red","blue","green","yellow","black","white","pink","orange","brown"] AS x,
  ["blue","white","pink"] AS y
RETURN [i IN x | CASE WHEN i IN y THEN "" ELSE i END] AS result

returns:

╒══════════════════════════════════════════════════════════╕
│"result"                                                  │
╞══════════════════════════════════════════════════════════╡
│["red","","green","yellow","black","","","orange","brown"]│
└──────────────────────────────────────────────────────────┘