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mysql query messages and replies to the same topic

Posted on 2009-07-07
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Last Modified: 2012-05-07
I have table described below of messages. I want to display all messages initiated by a specific user, as well as all other messages that replied to the same topic as that message. Then I would need that sorted by date. So essentially, it creates a list of messages, and responses to those messages (so users can see what they wrote, and what people responded after them).

What it is essentially excluding is, messages written by other users on topic the subject user is not participating in, or messages written by other users on a topic before the subject user has participated.

I've attempted what I think the query might look like
messages table
------------------
message_id
topic_id
user_id (person who created the message)
date
 
attempted query
-------------------
select * from messages 
where user_id = '14'
or where exists (select * from messages as messages2 where messages.topic_id = messages2.topic_id and user_id != '14' and messages2.date > messages.date)

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Question by:MeridianManagement
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Expert Comment

by:waygood
ID: 24802051
How are you distinquishing which message is a start of a topic? as you've only provided info on the messages.
Do you have a topic table too? as placing the person who started the topic in this table also would be easier
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MeridianManagement earned 0 total points
ID: 24804275


this code does what I am looking for.
select * from messages 
where user_id = '14'
or exists (select * from messages as messages2 where messages.topic_id = messages2.topic_id and user_id = '14' and messages2.date > messages.date)

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