c# - Linq Query Count and GroupBy -

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can tell me how sql query in linq?

select [id], count(*) [data].[dbo].[mytable] group [id]

you can try approach:

 var res = ctx.mytable  // start table     .groupby(r => r.id) / group key of choice     .select( g => new {id = g.key, count = g.count()}) // create anonymous type w/results     .tolist(); // convert results list

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