sql - How to group all conversations in a database by date, conversation thread -

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i've got sqllite database has log of received , sent messages.

id    sender     msg                    timestamp 1     2        9    1-1                    201 2     9        2    1-2                    202 3     1        9    2-1                    203 4     9        2    1-3                    204 5     9        1    2-2                    205

i can order them timestamp, when conversations overlap example above (between 9, 2, , 1) kills readability.

how show them conversation?

ie:

id    sender     msg                    timestamp 1     2        9    1-1                    201 2     9        2    1-2                    202 4     9        2    1-3                    204 3     1        9    2-1                    203 5     9        1    2-2                    205

in database conversations between 9 , number, example 2 , 1 never have conversation.

i've input data sqlfiddle here

to conversations in order started, you'll need self join table minimum timestamp per conversation, , order minimum id conversations in order , secondarily timestamp of message messages in order.

select a.id, a.sender, a."to", a.msg, a.timestamp table1 join table1 b   on case when a.sender=9 a."to" else a.sender end =      case when b.sender=9 b."to" else b.sender end  group a.id, a.sender, a."to", a.msg, a.timestamp order min(b.timestamp), a.timestamp

an sqlfiddle test with.


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