ASP.NET + memcached - where and when should I check for conditions to invalidate data?

I am concerned about how and when to check for conditions that warrant invalidating data in the cache.

I'm thinking in terms of e-commerce product listing or user-profile information.

Should this be done with a separate service that runs periodically that checks for old or changed data?

Should we rely on datab开发者_运维问答ase triggers to let us know when updates or inserts occur?

Thanks

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I'd recommend trying to use the Sql Dependency implementation on the cache. Check out this article...

http://msdn.microsoft.com/en-us/library/ms178604.aspx