SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function firstNonDefault (children 1)
     ExpressionList (children 2)
      Function CAST (children 1)
       ExpressionList (children 2)
        Literal NULL
        Literal \'Nullable(Array(UInt8))\'
      Function CAST (children 1)
       ExpressionList (children 2)
        Literal \'[]\'
        Literal \'Array(UInt8)\'
