jeudi 5 novembre 2015

Sqlite Order by Before Group By Like Mysql

I am working on a android sqlite db

I have 2 tables: chat, chat_messages

chat  
|_id |chatName      
 1   first
 2   second

chat_messages 
|_id |Chat_chatId |chatMessageContent |chatMessageId
 1      1         ttyl              4
 2      1         busy              3
 3      2         hi                2
 4      1         hi howdy          1


I want display a page showing latest chatMessageContent per chat like below

result
|chatName |chatMessageContent  |chatMessageId 
first      ttyl                4
second     hi                  2

Since the data restored from server was out of order, the latest chatMessageContent per chat need to follow chatMessageId desc

If Mysql the subquery works

Select * from (Select c._id,c.chatName,cm._id,cm.chatMessageContent,cm.chatMessageId from chat c, chat_message cm where cm.Chat_chatId = c._id order by cm.chatMessageId desc ) as lc GROUP BY lc.Chat_chatId

But it is not working for sqlite

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