SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function materialize (alias k) (children 1)
     ExpressionList (children 1)
      Literal UInt64_1
   Function or (children 1)
    ExpressionList (children 2)
     Literal NULL
     Function or (children 1)
      ExpressionList (children 3)
       Literal UInt64_0
       Function equals (children 1)
        ExpressionList (children 2)
         Identifier k
         Literal UInt64_2
       Function or (children 1)
        ExpressionList (children 2)
         Function equals (children 1)
          ExpressionList (children 2)
           Identifier k
           Function CAST (children 1)
            ExpressionList (children 2)
             Literal UInt64_1
             Literal \'Nullable(UInt8)\'
         Function equals (children 1)
          ExpressionList (children 2)
           Identifier k
           Literal UInt64_3
