GridView not populating, but not all the time, clearing cache fixe
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From: jjb3rd on 22 Apr 2010 10:35 I have essentially a working website. It has an Administration page, a CreateUser page, a Login page, a HospitalAccess page (for searching for a list of reports and displaying them in a GridView) and a FinalChart page which displays the report the user clicks on in the HyperlinkBoundField in the GridView from the HospitalAccess page. So, essentially, we have a site with 2 user pages, Hospital Access handles searching and displaying of results in a Sortable GridView with multiple pages. The left-most column in the gridview is a hyperlink bound field pointing to the finalchart page referencing the report id, whereupon the report is displayed. Simple enough and it works well....or so I thought until we went to deploy this in our test environment and have the eventual end users start evaluating it. Seemingly at random some users were getting our "No Records Found!" message, indicating we got an empty result set, even though we should have gotten results. So, I stayed up late, rewrote the whole thing essentially, simplifying the whole site...we deploy to testing again...same thing. This time around someone notices that clearing the browser cache fixes the problem. This problem has cropped up on IE6, IE7, IE8, Google Chrome and Firefox...I didn't try Safari long enough, but my guess is it would have the same results. Due to the clearing of the cache seemingly fixing the problem, I suspect that it has to due with our use of session variables to save both the DataSet of search results, as well as the sort column and order. Not sure how to program around that without doing things really old school, which is fine, but not really. So, like I said, this thing works, even in the testing environment, but after a while it stops working and you have to clear your cache to make it work again...in any browser, on XP 32 bit and Win 7 x64 alike. To further complicate things, some users (hospitals) have very restrictive user policies (obviously) and some are still using IE6, so there's that.
From: Gregory A. Beamer on 22 Apr 2010 11:53
"jjb3rd" <jjb3rd(a)discussions.microsoft.com> wrote in message news:BD648E8B-A907-4079-8B5A-23E501A63D79(a)microsoft.com... > > Due to the clearing of the cache seemingly fixing the problem, I suspect > that it has to due with our use of session variables to save both the > DataSet > of search results, as well as the sort column and order. Not sure how to > program around that without doing things really old school, which is fine, > but not really. Session variables get a bit nasty some times, but I think it is how you are using cache, assuming you mean server cache. If the needs are quite variable (different users see a different set), using cache may actually be detrimental to your application, as you end up with a bunch of stuff in cache. As the problem is intermittent, one suggestion is the cache is being cleared for one user just as he clicks and the app thinks it is pulling a "no record" from cache, as the cache is cleared. This is true of anything with weak references. Cache, in a UI sense, is best when there are a few sets of variables that can display the item(s) that are cached. Once the list get to be a matrix, cache is less and less useful and can end up being more of a headache than an aspirin (a cure?). If you mean browser cache, expire the page quickly and allow the list to be hit each time, avoiding cache ... that is one option. -- Peace and Grace, Greg Twitter: @gbworld Blog: http://gregorybeamer.spaces.live.com ************************************************ | Think outside the box! | ************************************************ |