SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Function plus (alias c) (children 1)
     ExpressionList (children 2)
      Identifier b
      Literal UInt64_1
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 2)
          ExpressionList (children 1)
           Function plus (alias b) (children 1)
            ExpressionList (children 2)
             Identifier a
             Literal UInt64_1
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             Subquery (children 1)
              SelectWithUnionQuery (children 1)
               ExpressionList (children 1)
                SelectQuery (children 2)
                 ExpressionList (children 1)
                  Function plus (alias a) (children 1)
                   ExpressionList (children 2)
                    Identifier x
                    Literal UInt64_1
                 TablesInSelectQuery (children 1)
                  TablesInSelectQueryElement (children 1)
                   TableExpression (children 1)
                    TableIdentifier table_1
   Set
