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POWhy is .Contains slow? Most efficient way to get multiple entities by primary key?
primarykey
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8107439
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8108643
AnswerCount
5
ClosedDate
CommentCount
5
CommunityOwnedDate
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2011-11-12T20:42:40.660
FavoriteCount
30
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2018-07-22T22:08:28.093
LastEditDate
2015-11-30T16:12:45.753
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14357
OwnerUserId
617027
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0
PostTypeId
1
Score
52
ViewCount
28966
LastEditorDisplayName
text
Body
What's the most efficient way to select multiple entities by primary key? <pre><code>public IEnumerable<Models.Image> GetImagesById(IEnumerable<int> ids) { //return ids.Select(id => Images.Find(id)); //is this cool? return Images.Where( im => ids.Contains(im.Id)); //is this better, worse or the same? //is there a (better) third way? } </code></pre> I realise that I could do some performance tests to compare, but I am wondering if there is in fact a better way than both, and am looking for some enlightenment on what the difference between these two queries is, if any, once they have been 'translated'.
Tags
<c#><.net><entity-framework><linq><entity-framework-4.1>
Title
Why is .Contains slow? Most efficient way to get multiple entities by primary key?
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 POWhy is .Contains slow? Most efficient way to get multiple entities by primary key?
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 POWhy is .Contains slow? Most efficient way to get multiple entities by primary key?
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1. COWell, thats indeterminate, usually not a huge number, but would like to be able to support large numbers in a scalable fashion.
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 POWhy is .Contains slow? Most efficient way to get multiple entities by primary key?
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