SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function materialize (alias m) (children 1)
     ExpressionList (children 1)
      Function map (children 1)
       ExpressionList (children 4)
        Literal UInt64_1
        Literal UInt64_2
        Literal UInt64_3
        Literal NULL
   ExpressionList (children 3)
    Function arrayElement (children 1)
     ExpressionList (children 2)
      Identifier m
      Function toNullable (children 1)
       ExpressionList (children 1)
        Literal UInt64_1
    Function arrayElement (children 1)
     ExpressionList (children 2)
      Identifier m
      Function toNullable (children 1)
       ExpressionList (children 1)
        Literal UInt64_2
    Function arrayElement (children 1)
     ExpressionList (children 2)
      Identifier m
      Function toNullable (children 1)
       ExpressionList (children 1)
        Literal UInt64_3