SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 2)
    Function overlay (children 1)
     ExpressionList (children 3)
      Literal \'Spark SQL\'
      Function materialize (children 1)
       ExpressionList (children 1)
        Literal \'_\'
      Literal UInt64_6
    Function overlayUTF8 (children 1)
     ExpressionList (children 3)
      Literal \'Spark SQL和CH\'
      Function materialize (children 1)
       ExpressionList (children 1)
        Literal \'_\'
      Literal UInt64_6
