How to create updateable resultset using sql with "order by"

Question

Dear all,
I'm using the Derby database to hold a table of stock prices. After the table is populated, I want to do some calculations and store the result in a column.
I get the resultset using the following code
Statement stmt = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE); ResultSet rs = stmt.executeQuery(select history_id, value, days from history where ticker = '" + ticker + "' order by value_date"); {code} When I then try to update the "days" field, I get an SQLException telling me that the resultset is not updatable. However, if I remove the "order by" clause, I am able to update the data, but then my algorithm does not work as I need to traverse the data in a specific order. The quesion is: how do I create an updatable resultset using a sql-statement with an order by clause? Kind regards Karl Martin Lund                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               

Answer 1

jschell wrote:
Seems rather obvious to me that the exception specifically tells you that you can't do that.OP: I would guess it's because ORDER BY forces the database to read all the result rows into a temporary area, sort them, and then return them from this temporary area, as opposed to streaming the results. The extra step probably makes updateable result sets more difficult (or maybe not possible), so they opted not to do it.