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Linq left requires syntax correction

I'm having trouble figuring out the syntax Linqfor a left outer join in multiple joins. I want to make a left join in a table RunLogEntryto get records that match this table, as well as all service records.

Can someone fix my snytax?

 var list = (from se in db.ServiceEntry
    join u in db.User on se.TechnicianID equals u.ID
    join s in db.System1 on se.SystemID equals s.ID
    join r in db.RunLogEntry on se.RunLogEntryID equals r.ID
    where se.ClosedDate.HasValue == false
    where se.ClosedDate.HasValue == false
        && se.Reconciled == false
    orderby se.ID descending
    select new ServiceSearchEntry()
    {
        ID = se.ID,
        ServiceDateTime = se.ServiceDateTime,
        Technician = u.FullName,
        System = s.SystemFullName,
        ReasonForFailure = se.ReasonForFailure,
        RunDate = r.RunDate
    })
    .Skip((page - 1) * PageSize);
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1 answer

Use the .DefaultIfEmptyon method rto perform a left join:

var list = (from se in db.ServiceEntry
    join r in db.RunLogEntry on se.RunLogEntryID equals r.ID into joinRunLogEntry
    from r2 in joinRunLogEntry.DefaultIfEmpty()
    join u in db.User on se.TechnicianID equals u.ID
    join s in db.System1 on se.SystemID equals s.ID
    where se.ClosedDate.HasValue == false
    where se.ClosedDate.HasValue == false
        && se.Reconciled == false
    orderby se.ID descending
    select new ServiceSearchEntry()
    {
        ID = se.ID,
        ServiceDateTime = se.ServiceDateTime,
        Technician = u.FullName,
        System = s.SystemFullName,
        ReasonForFailure = se.ReasonForFailure,
        RunDate = (r2 == null ? (DateTime?)null : r2.RunDate)
    })
    .Skip((page - 1) * PageSize);
+5
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