Is SQL DATEDIFF(year, ..., ...) an Expensive Computation?

Posted by rlb.usa on Stack Overflow See other posts from Stack Overflow or by rlb.usa
Published on 2010-03-30T17:41:59Z Indexed on 2010/03/30 17:53 UTC
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sql

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query-optimization

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datediff

I'm trying to optimize up some horrendously complicated SQL queries because it takes too long to finish.

In my queries, I have dynamically created SQL statements with lots of the same functions, so I created a temporary table where each function is only called once instead of many, many times - this cut my execution time by 3/4.

So my question is, can I expect to see much of a difference if say, 1,000 datediff computations are narrowed to 100?

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