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sigmas
Posting Yak Master
172 Posts |
 Posted - 2013-07-17 : 15:13:48
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| Is there an efficient index for this query?use northwindSelect orderid, customerid, employeeid, orderdate, RequiredDateFrom(Select dense_rank() over(partition by employeeID order by orderdate desc) as rnk,*From orders)dWhere rnk = 1; |
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LoztInSpace
Aged Yak Warrior
940 Posts |
Posted - 2013-07-17 : 15:49:04
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| possibly employeeID, orderdate desc but depends on how much data you have and what else is going on. |
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LoztInSpace
Aged Yak Warrior
940 Posts |
Posted - 2013-07-17 : 18:14:24
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| What are you hoping for? You can't answer that query without a scan on either an index or a table. |
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