SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 4)
   ExpressionList (children 3)
    Identifier a
    Identifier b
    Identifier c.UInt64.null
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier optimize_lazy_materialization_with_variant_data_type
   ExpressionList (children 1)
    OrderByElement (children 1)
     Identifier b
   Literal UInt64_10
