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How are internal, left and right outer joins implemented in SQL Server?

I am looking for a high-level algorithmic understanding so that I can get a Big-O idea of ​​what SQL Server does to perform joins. Feel free to be concise, I'm not looking extremely sensitive. What prompted me to understand how associations are better implemented is the scenario of this issue , which I also posted. I felt that they were ultimately two separate questions, although, therefore, I did not combine them.

Thanks!

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3 answers

Here are some readings to get you started.

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SQL Server can choose from many different joins: the most common are merge, loop, and hash. See KB article.

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Honestly, if you are interested in this level of detail, I would suggest you read: http://www.amazon.com/Microsoft-SQL-Server-2008-Internals/dp/0735626243/ref=sr_1_1?ie=UTF8&qid=1297976127& Wed = 8-1 # _

And learn to read execution plans. SQL Server has a pretty good optimization mechanism. This does not always do what we humans expect, albeit or even the same, for two queries that seem similar to us.

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