How to join tables with linq

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How can i convert the following line of code in a singe linq query

What I have tried:

var shopIds = await _business.TArtikelShops.Where(x => x.KArtikel == kArtikel).Select(y => y.KShop).ToListAsync();

var addresseIds = await _business.TInetAdresseShops.Where(x => shopIds.Contains(x.KShop)).Select(y => y.KAdresse).ToListAsync();

var countries = await _business.TAdresses.Where(x => addresseIds.Contains(x.KAdresse)).Select(y => y.Land).Distinct().ToListAsync();

return countries;

Posted 16-Jun-22 20:25pm

Member 15676982

Updated 16-Jun-22 21:49pm

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Richard Deeming · Answer 1 · 2022-06-16T21:49:00

Should be simple enough:

C#

var shopIds = _business.TArtikelShops.Where(s => s.KArtikel == kArtikel).Select(s => s.KShop);
var addresseIds = _business.TInetAddresseShops.Where(a => shopIds.Contains(a.KShop)).Select(a => a.KAddresse);
var countries = _business.TAddresses.Where(a => addresseIds.Contains(a.KAddresse)).Select(a => a.Land).Distinct();
return await countries.ToListAsync();

Only one query will be issued, on the ToListAsync call.

If you want everthing on a single line of C#, you could inline the three variables into the return line.