Join unrelated tables through a second level connected table

Posted by Andy M on Stack Overflow See other posts from Stack Overflow or by Andy M
Published on 2010-12-26T06:00:23Z Indexed on 2010/12/26 6:54 UTC
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Filed under:

sql

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mysql

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mysql-query

Hello!

I have two tables of activities on a page: Views & Comments.

Views
id
timestamp
project_id
user_id
page_id

Comments
id
timestamp
project_id
user_id
page_id
comment

Pages
id
project_id
title

Now pages are related to projects:

Projects
id
account_id
title

I am trying to create a summary page that combines views and comments ordered by time (so that the most recent views/comments are at the beginning, grouped by projects. Also, only projects for a specific account.

So the result could potentially be:

Project 1

View 5 (June 20th)
View 4 (June 18th)
Comment 5 (June 15th)
Comment 4 (June 14th)
Comment 3 (June 12th)

Project 3

View 3 (June 10th)
View 2 (June 8th)
Comment 2 (June 7th)

Project 2

View 1 (June 5th)
Comment 1 (June 4th)

If you could help with how to do this using SQL (or even doctrine) that would be awesome.

Thank you.

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