Question

I am kind of a newbie at programming (have worked a bit with Delphi years back) but have started to build an application for Windows Phone 7.5 Mango, as I have a great idea for an app 😀
In the application the user should be able to pick different locations from a list (a very large list, 5k+ items) – to make sure that all users always get the latest list, I have created a SQL on my website to generate the list as XML – which I load to the application via httpwebrequest; I am not quite sure what best practise is when dealing with a large list, which will be updated frequently etc.?

That is not the main question thou, because this seems to work pretty okay – my real question is, how to add a search function to my application, so the user can search for a location instead of scrolling throug the entire list?

My SQL is build up with ID, Country, State, Region, City (and a few more irrelevant tables for a search function).

I do not know what the best way to approach this is? Should I make a query on my website and generate the result as XML and use httpwebrequest to get the result to the phone – or should it be a search function on the device to search the entire list? And if so, how do I do that?

Thank you 😉

Answer 1

First of all I have to inform you that fetching an list with over 5k+ items via a smartphone that not are using Wireless Network, will take a while. So, acrording to me there would be a huge waste of traffic to download the whole list if the user only are interested in a few items. This basically means that you are downloading a bunch of date but only are using 0,01% of it which is not the way you should build a program.

So, acording to me you should make an webservice so that the user can call the webservice and make a http request using its search parameter. And then you basically just use the parameter in an SQL Search Query, which could be an stored procedure or just bare in code, but I don’t know how your server/database is build and structed so you can basically choose that whatever.

Here is an example:

SELECT * FROM TABLE_NAME WHERE (ID=@ID) OR (Country=@Country) OR (State=@State) OR (Region=@Region) OR (City=@City)

If i would have done this application I would have had two parameters. One that are representing the user input, in other words the search text and one that explains what the serach parameter is. (ID, Country, State, Region or City?).