* Thus wrote Lenar Lhmus:
> Mattias Thorslund wrote:
> 
> > Though, (regardless of SQL database platform) in a case like this, it
> > MAY be both more straightforward and efficient to use two separate
> > queries for the pictures and comments, given the one-to-many cardinality
> > between them.  The above statement causes redundant data to be returned
> > - it duplicates the pics record for each new comment.  If there are many
> > large columns in the pics table and many comments to each record there's
> > a lot of redundant data in a query like that.
> 
> No, I think you are wrong. There was GROUP BY pics.id so it won't return
> duplicate data. And probable overhead is eliminated too I think - DBserver
> will optimize and will join data from pic_comments only once for each
> unique pics.id.

The results will be something like:

id submitter count pic_id comment
1  joe        4      1    comment1
1  joe        4      1    comment2
1  joe        4      1    comment3
1  joe        4      1    comment4
2  john       0      2    NULL
3  jim        5      3    comment6
3  jim        5      3    comment7
3  jim        5      3    comment8
3  jim        5      3    comment9
3  jim        5      3    comment10



Curt
-- 
First, let me assure you that this is not one of those shady pyramid schemes
you've been hearing about.  No, sir.  Our model is the trapezoid!

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