global variable v/s cache

[need2progm]

Could someone tell me the difference or why I should use one over the other?

I am using asp.NET (2.0) to do a rewrite of an application to be released March of next year. I am little confused why I should cache something verse just putting a populated DataTable as a global variable at app start.

 

[checkai]

it's actually a good question, i've always been told to(and have) stayed away from the global variable method, if i've updated my database, i'll reset my cache object to make sure i have the newest data in it..

"...we both know I'm training to become a cagefighter...see what happens if you try 'n hit me..."

 

[stsuing]

When you cache something you can control when it is released and re-cached. So if you had a table that is updated nightly, you could retrieve that data, cache it for 1 day and then get it again tomorrow automatically. You can even release cached items if a file changes. Plus you can cache pages or controls by post/get parameters which increases the response from your server.

You don't get that functionality with global variables.

Hope this helps.

http://samples.gotdotnet.com/quickstart/aspplus/doc/datacaching.aspx

 

[dragonwell]

fwiw

Unlike data stored in the Application object, items stored in the Cache object can have a number of additional attributes applied to them, including an expiration policy, a priority, and one or more dependencies. These attributes form the substrate of the advanced Cache features such as the ability to remove least-used items, have items expire at a given time, and set logical connections between a group of items and disk files.

http://www.codeproject.com/useritems/Caching_Mechanism.asp