SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Asterisk
   TablesInSelectQuery (children 2)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (alias t1) (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 3)
          ExpressionList (children 2)
           Identifier key
           Function sum (alias val) (children 1)
            ExpressionList (children 1)
             Identifier val
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             TableIdentifier t1
          ExpressionList (children 1)
           Identifier key
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      TableIdentifier t2
     TableJoin (children 1)
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier t1.key
        Identifier t2.key
