Wayne, http://donteattoomuch.blogspot.com/2008/04/partial-ajax-update-capable-list-view.html This may be interesting too.
Regards - Cemal http://www.jWeekend.co.uk http://jWeekend.co.uk Wayne Pope-2 wrote: > > Thanks Matej, > > I just noticed org.apache.wicket.markup.repeater.AbstractPageableView<T> > which seems what I'm ofter - I'll have a look and both and get something > working. > > > On Wed, Nov 26, 2008 at 5:57 PM, Matej Knopp <[EMAIL PROTECTED]> > wrote: > >> You can just take AbstractPageableView, IDataSource and IGridSortState >> from the code. It should do exactly what you want and It shouldn't >> have any dependencies on the rest of grids. >> >> -Matej >> >> On Wed, Nov 26, 2008 at 5:39 PM, Wayne Pope >> <[EMAIL PROTECTED]> wrote: >> > Hi Matej, >> > >> >>The idea is always to load one row more than required on page which >> >>tells the grid if there will be a next page or not. >> > >> > Great idea. I looked at the code and I think I'll do my own (simplied >> > version) of your refreashingpage. I believe thats what we really want >> here, >> > as we don't care about telling the user the total amount of rows. >> > >> > Thanks everyone for your comments and help >> > Wayne >> > >> > On Wed, Nov 26, 2008 at 5:21 PM, Matej Knopp <[EMAIL PROTECTED]> >> wrote: >> > >> >> Hi Wayne, >> >> >> >> if you feel brave enough you can take a look at inmethod grid >> >> components (available in wicket stuff svn - >> >> http://wicket-stuff.svn.sourceforge.net/svnroot/wicket-stuff in trunk >> >> and 1.3 branch). The grid contains AbstractPageableView that can >> >> perform paging without having to know the number of rows upfront. >> >> >> >> The idea is always to load one row more than required on page which >> >> tells the grid if there will be a next page or not. >> >> >> >> -Matej >> >> >> >> On Wed, Nov 26, 2008 at 5:15 PM, Wayne Pope >> >> <[EMAIL PROTECTED]> wrote: >> >> > Hi James, >> >> > >> >> > its not killing anything at the moment, I just don't like the idea >> of >> >> > hitting the database with due cause. >> >> > However I thinking about this some more I believe perhaps I should >> not >> >> use >> >> > DataViews full stop - but RefreshingView instead?. Essentially I >> have >> in >> >> > several places a large data set. I'm only interested in displaying >> say >> >> the >> >> > first 10 rows. Then the user can click on "load next 10" and thus >> display >> >> > the next 'page' of results. They then have a choice of loading the >> next >> >> 10 >> >> > or the previous 10, etc. Perhaps DataView is not really suited to >> this >> >> type >> >> > of behaviour? more used where you want to see the number of pages a >> >> search >> >> > result finds for example? If we're at the edge condition that there >> are >> >> > exactly 20 results, when asking for the next 10, we simply disply >> the >> >> > message 'no more results'. >> >> > >> >> > >> >> >>We just issue a count(*) query first to get the count >> >> > Yes so this will be called every time the page is rendered no unless >> you >> >> > cache as you stated, but you run the risk changing dataset? >> >> > >> >> > thanks >> >> > Wayne >> >> > >> >> > On Wed, Nov 26, 2008 at 5:05 PM, James Carman < >> >> [EMAIL PROTECTED]>wrote: >> >> > >> >> >> We just issue a count(*) query first to get the count. Then, we >> use >> >> >> individual queries to get each page's data. If you feel confident >> >> enough >> >> >> that the count won't change (or you don't really care if it does), >> you >> >> can >> >> >> cache the value returned from it the count query (I don't know how >> often >> >> >> that gets called, really). If calling the queries to get the >> individual >> >> >> page's data is killing your database, then you're doing something >> wrong, >> >> >> IMHO. >> >> >> >> >> >> On Wed, Nov 26, 2008 at 10:32 AM, Wayne Pope < >> >> >> [EMAIL PROTECTED]> wrote: >> >> >> >> >> >> > Hi, >> >> >> > >> >> >> > thanks for the replies. >> >> >> > >> >> >> > Micheal O/Hoover - I still don't see how this works as you don't >> have >> >> the >> >> >> > limit and offset (that is used in Iterator). How do you know how >> many >> >> >> rows >> >> >> > to load in your size() method? >> >> >> > >> >> >> > Michael S - thanks for the link - it it appears I must completely >> >> rewrite >> >> >> > the whole pagable/provider code (not looked at the code) to get >> this >> >> to >> >> >> > work? >> >> >> > >> >> >> > I'm sure I must be missing something still, as I can't beleive >> that >> we >> >> >> need >> >> >> > to either a) load the whole data set b) call count on the Db , >> then >> >> load >> >> >> in >> >> >> > the iterator mehod. Thats going to kill the database in prod (or >> >> really >> >> >> not >> >> >> > help.) >> >> >> > >> >> >> > On Wed, Nov 26, 2008 at 3:58 PM, Michael Sparer < >> >> [EMAIL PROTECTED] >> >> >> > >wrote: >> >> >> > >> >> >> > > >> >> >> > > have a look at >> https://issues.apache.org/jira/browse/WICKET-1784 >> >> >> > > >> >> >> > > >> >> >> > > Wayne Pope-2 wrote: >> >> >> > > > >> >> >> > > > Ok, >> >> >> > > > >> >> >> > > > I was just having a bit of code clean up and I realized that >> in >> >> our >> >> >> > > > IDataProviders we are loading all rows for a given dataset. >> >> >> > > > So looking at the iterator method I see we can limit the >> result >> >> (and >> >> >> > the >> >> >> > > > offset). Great I thought - however I see that that the size() >> >> method >> >> >> is >> >> >> > > > called as part of the getViewSize() in the >> AbstractPageableView. >> >> Thus >> >> >> I >> >> >> > > > need >> >> >> > > > to call the database here to figure out the size. >> >> >> > > > >> >> >> > > > Am I doing sonething wrong or have I got to hit the database >> twice >> >> >> for >> >> >> > > > each >> >> >> > > > DataProvider render. >> >> >> > > > >> >> >> > > > Obvously I don't want to hard code a size. Is there any other >> way >> >> ? >> >> >> > > > >> >> >> > > > Thanks >> >> >> > > > Wayne >> >> >> > > > >> >> >> > > > >> >> >> > > >> >> >> > > >> >> >> > > ----- >> >> >> > > Michael Sparer >> >> >> > > http://talk-on-tech.blogspot.com >> >> >> > > -- >> >> >> > > View this message in context: >> >> >> > > >> >> >> > >> >> >> >> >> >> http://www.nabble.com/Is-there-any-other-way--DataProviders-must-hit-the-Db-twice-for-%28possible%29-large-datasets-tp20701684p20702476.html >> >> >> > > Sent from the Wicket - User mailing list archive at Nabble.com. >> >> >> > > >> >> >> > > >> >> >> > > >> >> --------------------------------------------------------------------- >> >> >> > > To unsubscribe, e-mail: [EMAIL PROTECTED] >> >> >> > > For additional commands, e-mail: [EMAIL PROTECTED] >> >> >> > > >> >> >> > > >> >> >> > >> >> >> >> >> > >> >> >> >> --------------------------------------------------------------------- >> >> To unsubscribe, e-mail: [EMAIL PROTECTED] >> >> For additional commands, e-mail: [EMAIL PROTECTED] >> >> >> >> >> > >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: [EMAIL PROTECTED] >> For additional commands, e-mail: [EMAIL PROTECTED] >> >> > > http://donteattoomuch.blogspot.com/2008/04/partial-ajax-update-capable-list-view.html http://donteattoomuch.blogspot.com/2008/04/partial-ajax-update-capable-list-view.html -- View this message in context: http://www.nabble.com/Is-there-any-other-way--DataProviders-must-hit-the-Db-twice-for-%28possible%29-large-datasets-tp20701684p20706800.html Sent from the Wicket - User mailing list archive at Nabble.com. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
