c# - linq sql - aggregate count -

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i have linq returns correct data.

var numemails = (from row in emailbatchproposal   row.emailbatchid == emailbatchid select row.emailbatchproposalid).count();

however, if understand linq correctly, not perform optimally. grabs data , walks through list , counts rows. i'd linq (in background) use like:

select count(*) ...

i trust performance reasons obvious.

does know proper way this?

actually, if linq query used collection implements iqueryable , supports translation underlying sql variant, quite basic functionality translate count function example correctly.


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