SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function arrayFirstIndex (children 1)
     ExpressionList (children 2)
      Function lambda (children 1)
       ExpressionList (children 2)
        Function tuple (children 1)
         ExpressionList (children 1)
          Identifier x
        Function materialize (children 1)
         ExpressionList (children 1)
          Literal UInt64_0
      Function arrayMap (children 1)
       ExpressionList (children 2)
        Function lambda (children 1)
         ExpressionList (children 2)
          Function tuple (children 1)
           ExpressionList (children 1)
            Identifier x
          Function toString (children 1)
           ExpressionList (children 1)
            Identifier x
        Literal Array_[UInt64_1, UInt64_2, UInt64_3]
