SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 3)
    Function sumMerge (children 1)
     ExpressionList (children 1)
      Function plus (children 1)
       ExpressionList (children 2)
        Identifier x
        Identifier y
    Function sumMerge (children 1)
     ExpressionList (children 1)
      Identifier x
    Function sumMerge (children 1)
     ExpressionList (children 1)
      Identifier y
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 2)
          ExpressionList (children 2)
           Function sumState (alias x) (children 1)
            ExpressionList (children 1)
             Identifier a
           Function sumState (alias y) (children 1)
            ExpressionList (children 1)
             Identifier b
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             TableIdentifier add_aggregate
