linq left join group by
Code Example - linq left join group by
from p in context.ParentTable
join c in context.ChildTable on p.ParentId equals c.ChildParentId into j1
from j2 in j1.DefaultIfEmpty()
group j2 by p.ParentId into grouped
select new { ParentId = grouped.Key, Count = grouped.Count(t=>t.ChildId != null) }
linq left join
IQueryable<Job> jobs = (from j in _db.Jobs
join jt in _db.JobTranslators on j.Id equals jt.JobId into jts
from jtResult in jts.DefaultIfEmpty()
join jr in _db.JobRevisors on jtResult.Id equals jr.JobId into jrs
from jrResult in jrs.DefaultIfEmpty()
join u in _db.Users on jtResult.UserId equals u.Id into jtU
from jtUResult in jtU.DefaultIfEmpty()
where jtUResult.Id == userId
orderby j.Id
select j).Concat(
from j in _db.Jobs
join jt in _db.JobTranslators on j.Id equals jt.JobId into jts
from jtResult in jts.DefaultIfEmpty()
join jr in _db.JobRevisors on jtResult.Id equals jr.JobId into jrs
from jrResult in jrs.DefaultIfEmpty()
join u in _db.Users on jrResult.UserId equals u.Id into jrU
from jrUResult in jrU.DefaultIfEmpty()
where jtUResult.Id == userId
orderby j.Id
select j
).Distinct()