Forms Data Controls :: Caching DataTable - Create/cache Multiple DataTables?
Jul 23, 2010
Among the many aspects of asp.net that I haven't focused my development on yet is caching. I have a perfect application for it now, I think, with a GridView that sits inside a repeater, and is bound in the Repeater ItemDataBound event. The contents of the GridView will remain static for each Repeater data item for each Client. The nature of the data in the GridView is that it can change from day to day per Client, but wouldn't need to be refreshed more frequently than that. The Page istelf only deals with one at a time Client based on a QueryStringParameter. My questions are a) how do I cache the DataTable so that a call to the DataBase isn't made each time Repeater item is bound and b) can I create/cache multiple DataTables (one for each Client) and let them live for day, checking for existence before calling the SQL stored procedure to regenerate the data?
I've got a web application that runs of a state server. It looks like soon it may need to distributed and there will be two web servers behind a load balancer.
This works great for session state but my next challenge is Cache
My application leverages heavily of cache. I understand ASP.Net 4.0 will be offering more here but nothing much has been said about the how too.
There are two challenges that I face
1). Each webserver will have its own copy of cache whereas it would be more efficient to put this to a third server the same as session state is put to state server.
2). The real challenge is keeping cache in sync if a simple dataset derived from the database is changed my code dumps that cache item and reloads the cache. That's all well on one webserver but webserver number two wont know to drop that particular cache item and reload it. This could cause some unexpected problems in the application.
For scenario number 2 I could attempt to do some smart coding so server number two knows to dump the cache and reload it.
My guess is someone else has already been here before and there's probably a better implementation approach rather than writing extra code.
Does anyone know how I could achieve the goal of keeping Cache in sync between multiple webservers or even better farm Cache management to another server?
I have 2 views in sql server and I create a dataset with those 2 views as datatables. Now I need to create a datatable and programmatically fill it with the other 2 datatables. Take the 2 datatable and create a third one in the dataset not create a third view in sql server.
since asp.net contains multiple threads that are executing at the same time.so if 2 threads access an object (simple or complex) that i got from the the asp.net httpcontext Cache.can't this lead to state problems on that object if these 2 theads tried to modify/read it at the same time?so what kind of precautions should i implement?for example i am thinking maybe locking the object while working with it? (wont this cause performance problems?)or maybe when i retrieve some object from the cache i should create a copy from it? or maybe i dont need to worry about this issue at all?
Does dataset store all its datatables' records into server memory if I just call one datatable from it?Lets make an example, a dataset with three datatables - tbCompany, tbCompanyStaffs, tbSalesOrderwhere tbCompany is the parent of tbCompanyStaffs. tbSalesOrder is an independant table.Does dataset load all tbCompanyStaffs records into the server memory as well when a class retrive data from tbCompany?
In our .aspx pages we have user controls each control has a Sql query to fetch data. The caching mechanism to be followed says that fragment cache all the user controls and invalidate the cache based on the respective queries of the user control.How to proceed to add a query dependency to fragment cached user control?
I need to remove the data stored in the cache after few minutes (Output and Data Cache).
My concept is binding data from server, storing it in to cache and displayed in the gridview, after a 10 seconds when the button is clicked the cache data should removed and need to show null like nothing. I have build some basic of code, how to get perfectly. I am new to dotnet.
find the below required points and attachments of asp.dot net code and sql query.
1. When page load, gridview should display using Cache.
2. when Clear Cache Button after 10 second from pageload is clicked then the gridview should go hide
3. Reload Cache Button is clicked the gridview again load.
I am trying to combine two datatables into single datatable... First table contains 3 columns[e.g: 'col1','col2','col3'] Second table contains 2 columns[e.g: 'col4','col5'] Both tables have the same no.of records[rows], but different columns. How to combine them into single table? I need DataTable with columns ['col1','col2','col3','col4','col5']. I am inserting through looping the both the tables and adding values into third table. I tried the Merge (DataTable.Merge()), but it is adding the records to bottom of first one, but i need it should be added to the side[as columns] to first table'
I am embarrassed to ask, but what is the best way to add key/value pair data in cache (HttpRuntime.Cache) to a DataTable?
I'm currently dumping the key/value pair data from cache into a HashTable, which becomes the DataSource for a Repeater object. Unfortunately, I cannot sort the data in the Hashtable and therefore thought a DataTable (being the DataSource for the Repeater) would solve my dilema.
What I have is a datatable being constructed from Sharepoint API. We dont need to worry about the sharepoint api.The code where it fills the data is as follows
Datatable dt = new datatable(); Sharepoint.fill(dt);
Write what I want is as the dt is being filled is to create another column called full path which has a formula col1+col2I dont want to do a for next loop after the dt is filled . very slow !
customer_id items 123 pen 123 paper 456 pen 456 paper 678 pen
then i pivot the gridview by using the datatable.. i call the sql query to the datatable, pivot it using pivoted function and the datatable then become the datasource bind to the gridview..the result of pivoted datatable in gridview as below:
my question is..how can i replace the empty column with textbox to be display within the gridview??? i need to use textbox so that user may enter the value of the item within the textbox.. i try using the itemtemplate for gridview but it's doesn't work and the itemtemplate create new column with textbox beside the paper column.. how to input textbox within the datatable in my case??
I need to do a total on one of the fields from the datatable but im not sure how to do it as i am not defining the itemtemplate for the column as its dynamic
SCANNER RESULT: Stock B, StockC (ideally this result would be displayed in a GridView)
Now this seems like an easy task for a simple SQL JOIN statement, but the problem is that the SQL statements I've written for some criteria are already so complex that it's unthinkable to combine them further by using a SQL JOIN statement.......(yes I've tried and failed).
I think the only way to accomplish this is to put each criteria-filtered result into an array or datatable, and then try to query to see which stocks exist in all the arrays/datatable (in other words satisfy all criteria), and to display these stocks in a gridview. After doing some research online, it is possible to do query from multiple datatables by either using:
JOINVIEW(DataRelation) or LINQ
But which one is the best method (if it works)? I didn't consider using a loop for this since it would be too inefficient, especially if a user select many criteria.
[OutputCache (Duration=20, VaryByParam="None" )] public ActionResult display() {}
This code cache whole page.But, my site has user infomation on top like this ASP.net. The user info "Signed as userid | Edit Profile | ..." section should be changed when user sign in/out. But rest of the page is always same and it's good to Cache.
If the above code is used, the user info on top also cached and give wrong info to user.
I have a List of objects in an asp.net page. when the page loads in the browser for the first time, I fetch data from the database, create objects with those data and populate the list. All these are done inside the page load event handler. Now when the page is posted back to the page, the previous list is gone, since the variables were all freed.
How can I cache that List, so that when this page is posted back, all my objects are available?
I'd like to pass data from one asp.net page to another. I've seen that using System.Web.Caching.Cache is a good way to accomplish this. I'm wondering if it's a good way to do it and also is there any cleanup or other things I need to keep in mind when you the Cache?
Last night I wrote up my first IHttpModule to do some request processing. I'm using a regular expression to inspect the raw url. The IHttpModule will be called on every request, so it seems reasonable to do some sort of caching of the regular expression object to prevent creation of it on every request.
Now my question... what is better: use the HttpContext.Current.Cache to store the instantiated object or to use a private static Regex in my module?I'm looking forward to the reasons why. Just to clarify: the regex will never change and thus always be the same thing.
I am building a web application using asp.net (c#) and lingtosql. When I perform update operations on my db I update my classes. I use gridview to bind to update information. When I relay solely on the database the page's take very long to load. When I relay solely on the cache, I have old data. What workarounds do I have for have asynchronous cache updating, yet not overload the database with endless requests (I'd like to update the cache only if there has been a change in the database itself, and perform the update operation asynchronously).
what the default serialization used by the ASP.net HttpRuntime.Cache is? Is it Binary, XML, something else?
I am populating a generic List with multiple objects of the same custom type. The custom type is a POCO, there is nothing special about it. All of its properties are public with { get; set; }, it is public, it has no inheritance, it has no interfaces. In fact it is much less complicated than many other objects which we are caching which work without issue. I have tried adding the [Serializable] attribute to the custom class and it has no effect.
I add the list to the cache with a unique key. The list has been verified as populated before it is inserted into the cache, the objects in the list have been verified as populated as well. But when the list is pulled back out of the cache it is an empty list (NOT NULL), it simply has no items in it. This means that the list is being added to the cache and is retrievable but for some reason the cache is having issues serializing the objects in the list.
I just find this freaky weird since I have another list of custom objects which are much more complicated (consisting of Inheritance, Interfaces, and also containing Properties which are generic lists of other complex objects) and the caching of those lists work without issue.
Both the working and non-working list are being managed in C# classes outside of the ASP.net user controls which consume the cached data. Both of these cache handling classes call the exact same Cache Manager class singleton instance which wraps the HttpRuntime.Cache to provide typed methods for pull and pushing objects into the cache.
We display an ASP.NET calendar control and update the color and if the day is enabled with the DayRender event. This process is a bit slow so I'm trying to map out a strategy to cache the results of the all the DayRenders. Basically take a snapshot of the calendar and cache it for X minutes. Where would I hook into the page/control workflow to accomplish this goal?
How to create Rows and Column using Datatable Gridview Itemtemplate with multi header I need to create Datatable Gridview Itemtemplate fixed rows and column such as 7 rows and 7 columns
I want to Get multiple selected column from datatable using c#. Below I have added data of datatable and I want red marked rows from datatable. Green marked text is column name of datatable.
Parameter Value GetTempFilenameResult 0 tempFilename 0 data 0 fid 0 useid 0 filename 0 tempFilename 0 userName 1 pwd 1 LoginResult 1 useid 2 usename 2 address 2 mobileno 2 emailid 2 organization 2 city 2 country 2 password 2
