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SQL question : JOIN and COUNT(*) in same query

Posted on 2005-03-30
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Last Modified: 2009-12-16
I need SQL for the following or i need to know if it is not possible, i know i can do it in two seperate queries but this isnt really an option.

I have two tables 'Users' and 'Ratings' I need to select each user from 'Users' and then order them depending on how many related records there are in the 'Ratings' table. eg. how many time they have been rated. They are related by the fields User.GUID to Ratings.RatingTo.

Cheers

Nick
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Question by:coolnicks
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3 Comments
 
LVL 35

Expert Comment

by:David Todd
ID: 13666546
Hi,

Off the top of my head try this ...

select user.GUID, count( * )
from user
inner join ratings
on User.GUID = Ratings.RatingTo
group by user.GUID
order by count( * ) desc

Notes:
a) you may need to edit this.
b) Adding additional columns complicates the group by functioning and may give wrong results. Sometimes the best way of doing this is to use the above in a subquery to return the count ... ask if you need this sketched out for you.

Regards
  David

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LVL 13

Accepted Solution

by:
KarinLoos earned 375 total points
ID: 13666554
select users.GUID,
         count(ratings.ratingsto)
from users  
join ratings on ratings.ratingsto = users.gui
order by users.guid
0
 

Author Comment

by:coolnicks
ID: 13697940
thank you both.

dtodd's solution returned the count corrently, but also returned 1, even if there was no matching record

KarinLoos's also worked, but didnt not return anything if there was no matching record, i ran with this code in the end but had to add the group by aswell.
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