Difference between revisions of "Extension talk:RecentActivity"

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(answered my own question)
m
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Now if we just wanted the last pages that were edited we'd say:
 
Now if we just wanted the last pages that were edited we'd say:
SELECT DISTINCT page FROM revision ORDER BY id DESC
+
{{code|<mysql>
 +
SELECT DISTINCT page FROM revision ORDER BY id DESC
 +
</mysql>}}
  
 
But we want the last articles ''created'' not just edited, so we need a list of the '''first revision''' of each article. Here's the same table with the first revision of each article marked
 
But we want the last articles ''created'' not just edited, so we need a list of the '''first revision''' of each article. Here's the same table with the first revision of each article marked
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I answered my own question - I created test table with those exact items in it and worked out the following query which gives the correct results:
 
I answered my own question - I created test table with those exact items in it and worked out the following query which gives the correct results:
<sql>
+
{{code|<mysql>
 
SELECT page,min(id) AS minid FROM rev GROUP BY page ORDER BY minid DESC LIMIT 3;
 
SELECT page,min(id) AS minid FROM rev GROUP BY page ORDER BY minid DESC LIMIT 3;
</sql>
+
</mysql>}}

Revision as of 09:50, 16 March 2009

Difficulty with last n created articles query

Lets say we have the following revision table:

 id |  page
----+----------
 1  |  Fred
 2  |  Sam
 3  |  Bob
 4  |  Bob
 5  |  Fred
 6  |  Harry
 7  |  Sam
 8  |  Mary
 9  |  Mary
10  |  Bob

Now if we just wanted the last pages that were edited we'd say:

<mysql>

SELECT DISTINCT page FROM revision ORDER BY id DESC </mysql>

But we want the last articles created not just edited, so we need a list of the first revision of each article. Here's the same table with the first revision of each article marked

 id |  page
----+----------
 1  |  Fred  *
 2  |  Sam   *
 3  |  Bob   *
 4  |  Bob
 5  |  Fred
 6  |  Harry *
 7  |  Sam
 8  |  Mary  *
 9  |  Mary
10  |  Bob

And those need to be listed with a limit and descending order as follows (say limit=3):

 id |  page
----+----------
 8  |  Mary
 6  |  Harry
 3  |  Bob

What is a query to do that?

I answered my own question - I created test table with those exact items in it and worked out the following query which gives the correct results:

<mysql>

SELECT page,min(id) AS minid FROM rev GROUP BY page ORDER BY minid DESC LIMIT 3; </mysql>