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From:ddevaudreuil Date:September 27 2006 3:03pm
Subject:Re: AW: Count of children
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I've found this website to be extremely helpful:

http://www.artfulsoftware.com/mysqlbook/sampler/mysqled1ch20.html

Donna DeVaudreuil




André Hänsel <haensel@stripped> 
09/27/2006 10:55 AM

To
<peter.brawley@stripped>
cc
<mysql@stripped>
Subject
AW: Count of children






I will use any model that is suitable. ;)

I am somewhat familiar with both tree models but I can't come up with a
method to get the count of all sub- and sub-sub-nodes in either of them.

> -----Ursprüngliche Nachricht-----
> Von: Peter Brawley [mailto:peter.brawley@stripped] 
> Gesendet: Mittwoch, 27. September 2006 16:49
> An: André Hänsel
> Cc: mysql@stripped
> Betreff: Re: Count of children
> 
> André,
> 
> >I want the count of all sub-entries for a specific entry.
> 
> Depends on the model you are using--edge list or nested sets?
> 
> PB
> 
> -----
> 
> André Hänsel wrote:
> > I have a table with id and parent_id.
> > I want the count of all sub-entries for a specific entry.
> >
> > I found several documents about working with graphs/trees 
> in MySQL but I
> > could not find a solution for my problem.
> >
> > I can imagine two possibilities, but one is memory 
> intensive and the other
> > one creates load on updates.
> > The first is, that I select all entries and then use a 
> procedural language
> > to determine recursively whether an node is a sub-node of 
> the specific node.
> > The second is, that I store the sub-node count with each 
> node and when I do
> > an insert, I walk the tree upwards and increment the node-counts.
> >
> > Is there a smart solution/best practice for my problem?
> >
> > Now I can't think of another sentence starting with an i. ;-)
> >
> > Best regards,
> > André
> >
> >
> > 
> 
> 
> -- 
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> Date: 9/26/2006
> 


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Thread
Count of childrenAndré Hänsel27 Sep
  • Re: Count of childrenjoao27 Sep
  • re: Count of childrenRob Desbois27 Sep
    • AW: Count of childrenAndré Hänsel27 Sep
    • Re: Count of childrenjoao27 Sep
      • Re: Count of childrenDouglas Sims27 Sep
  • Re: Count of childrenPeter Brawley27 Sep
    • AW: Count of childrenAndré Hänsel27 Sep
      • Re: AW: Count of childrenddevaudreuil27 Sep
      • Re: AW: Count of childrenPeter Brawley27 Sep
        • RE: AW: Count of childrenRobert DiFalco27 Sep