RowHandler is a solution, but not exactly what I've been looking for. Given another API which expects an Iterator over the dataset (like "I need to call BigStore.loadfrom(Iterator<DataItem>)") it is quite difficult to make the conversion from a RowHandler being called repeatedly to an Iterator. Not impossible, indeed: a limited length queue and some thread pumping events in it should do the trick.
Another project constraint is to use released third party modules only, so yes, I will have to implement the trick using RowHandler (and not to use the patch I was talking below). Thanks for the ideea, Corneliu Rudeanu --- Larry Meadors <[EMAIL PROTECTED]> wrote: > Oh, why didn't you say so in the first place? ;-) > > Use a RowHandler...or better still a stored procedure. > > Larry > > > On 9/14/05, Corneliu Rudeanu <[EMAIL PROTECTED]> wrote: > > > > Maybe I should have described the problem that determined me to > write > > the patch in the first place. I use iBATIS in a project where I > have to > > fetch some 4 million rows and process them. Using queryForList is > not a > > good ideea, since it would load all data in memory when returning > the > > results. I need to iterate the results, not to have them all at > once in > > memory. > > > > One dirty trick I applied was to get a java.sql.Connection from > > iBATIS's sqlMapClient > > (sqlMapClient.openSession().getCurrentConnection()) and solve the > > iteration by hand using JDBC code. I don't consider this a solution > and > > I would need iBATIS to offer such a "queryForIterable" method. If > > queryForPaginated list should remain as now, would you agree to the > new > > (iterable) method to be exposed by SQLMapClient? > > > > Best regards, > > Corneliu Rudeanu > > > > > > --- Brandon Goodin <[EMAIL PROTECTED]> wrote: > > > > > Tying up connections in the PaginatedArrayList would not be a > > > desireable functionality to me. I would recommend you write a > version > > > of PaginatedArrayList for your own personal use. If you are > handling > > > large resultsets I would recommend against the use of > > > PaginatedArrayList anyways. It is meant for small result > scrolling. > > > > > > Brandon > > > > > > On 9/13/05, Corneliu Rudeanu <[EMAIL PROTECTED]> wrote: > > > > > > > > > > > > Hi! > > > > > > > > I made a patch for SQLMapClient which allows reusal of > ResultSet's > > > > while iterating through a paginated query list. How can I > submit > > > the > > > > patch? > > > > > > > > A more detailed description: the current implementation is > > > re-running > > > > the query when user asks for some page, skipping the results > > > > (resultSet.next()) until the requested page is read. This is a > > > problem > > > > while iterating through large results, and in my opinion that > is > > > the > > > > exact purpose for having paginated queries. My patch keeps the > > > > ResultSet cached in the PaginatedList, and invokes next()'s > when > > > user > > > > asks for next page. When a page "from the past" (i.e. going to > a > > > page > > > > with lower index than current - 1) the query runs again, with a > > > > behaviour similar to current implementation. Note: the > optimization > > > > with next+previous pages being cached was kept in my patch. > > > > > > > > I have little experience with SVN. Please send some > instructions on > > > how > > > > to submit the patch in order to be evaluated. > > > > > > > > Regards, > > > > Corneliu Rudeanu > > > > > > > > > > > > > > > > > > > > ______________________________________________________ > > > > Yahoo! for Good > > > > Donate to the Hurricane Katrina relief effort. > > > > http://store.yahoo.com/redcross-donate3/ > > > > > > > > > > > > > > > > > __________________________________________________ > > Do You Yahoo!? > > Tired of spam? Yahoo! Mail has the best spam protection around > > http://mail.yahoo.com > > > __________________________________ Yahoo! Mail - PC Magazine Editors' Choice 2005 http://mail.yahoo.com
