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Message Posted: Tue, 29 May 2012 @ 17:31:03 GMT
Subj: | | Re: What is difference between Sample 10 and Top 10? |
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From: | | Walter, Todd |
The database is going to pick a statistically random sample of the result set to answer a SAMPLE query so it makes no difference if it is
sorted or not - the ORDERBY is extra work for no value.
TOP 5 means something different if on an ORDER BY query than on a query without ORDER.
With ORDER, it means exactly the TOP 5 of the sorted set.
Without ORDER it means get the first 5 it can find as quickly as possible.
The latter will be very fast if that is the result you want.
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