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aakcse
Aged Yak Warrior
570 Posts |
 Posted - 2009-06-24 : 08:27:49
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| Hi All, What is the difference between index scan and index seek.Regards,aak |
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Lumbago
Norsk Yak Master
3271 Posts |
Posted - 2009-06-24 : 09:51:11
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An index seek is a search in an index that is in the correct order given the search criteria, and the query optimizer will know exactly where to find the data it's looking for. If the index is not ordered correctly with a given search criteria you'll get a scan. Have a look at this dummy index:Col1 Col21 12 23 34 15 26 3 A "select * from table where col1 = 3" will give an index seek because the data is ordered and the query optimizer knows that it doesn't have to look any further in the index to find more corresponding values. A "select * from table where col2 = 3" will give a scan since the query optimizer doesn't know how many instances there are of 3 or where they are located.- Lumbago |
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Index scan and Index seek