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MySQL arranges order data in two ways

I am tracking pageviews in modules using the following table:

id | page_id | user_id | session_id | created

Each page is unique to a specific module; therefore page 14 exists, for example, only in module 2.

I'm trying to write a query that tells me when a browsing session (GROUP BY session_id) has started for a specific module, but I'm having problems with my order. Basically, for this grouped session, I want to return the earliest "created" (the time the browsing session started) and the last page_page (how far they got into the module).

What's the best way to do this?

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2 answers


I think you will need to use subqueries in select:



SELECT a.session_id, MIN(a.created) as start_time, 
b.page_id AS last_page, b.end_time
FROM table a 
INNER JOIN 
   (SELECT b.session_id, MAX(b.created) as end_time, MAX(b.page_id) 
   FROM table b GROUP BY b.session_id) 
ON a.session_id = b.session_id GROUP BY a.session_id
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SELECT  MIN(created), MAX(page_id)
FROM    modules
GROUP BY
        session_id


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