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Joel on Software
n-tier architecture abstraction
I think I understand the concept of a multi-tier system. However, most of the .net samples I've seen don't seem to have much abstraction between layers. (ASPX generating SQL statements is not abstract!) This is for a web form, so the ASPX = run on central server bit makes it more confusing.
definatly do all sorting and stuff through the database. Databases' were made to do this sort of thing. If your sql isn't horrible, it will almost always be faster then any algorithm you can come up with programaticly, front end or not.
This is an excellent book on designing scalable systems using MS technology. It's about COM+, but it all applies to .NET as well:
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