vb.net - Select all messages but not if the subject id is the same -

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i trying select messages written from_id display latest message same subject id. example messaging table looks this:

id from_id to_id subject subject_id date [content] percentage

each message created unique id, if message in same message chain i.e. follow on message subject id same message id. have code select current user that's logged in :

dim query = p in db.messages select p p.from_id = userid

but unsure how group newest message same subject id. in advanced.

i'm not visual basic expert, can use group by group returned messages subjectid , select latest message each of groups using select. syntax looks this:

dim q = p in db.messaes         p.from_id = userid         group subject = p.subject_id          messages = group         select ...

the ... bit needs replaced subquery returns latest message messages in current group (available in messages).


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