EXISTS/NOT EXISTS vs. IN/NOT IN

I've read there are two advantages of EXISTS. One is that EXISTS can perform faster than IN under certain circumstances. The other advantage I've heard is that there are some queries that cannot be done with IN, but can be done with EXISTS.

Could someone post the reasoning behind performance gains?

Could someone also post a good example of when only EXISTS will work?

Thanks!

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Before you buy. Received on Mon Mar 27 2000 - 17:03:24 CST