From: Peter Brawley
Date: January 20 2012 4:33pm
Subject: Re: mysql guru??
List-Archive: http://lists.mysql.com/mysql/226640
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On 1/20/2012 5:54 AM, bruce wrote:
> Hi.
>
> Got a major pain that I'm trying to solve using mysql.
>
> Trying to handle a hierarchical tree structure, where I have a
> parent/child structure that grows as data is added to the system.
>
> The process needs to continuously determine if the overall tree, and
> all the associated nodes/leafs have "completed" so not only is the
> tree growing, but data for the given node/leaf is also changing,
>
> The system is comprised of a parent app which spawns descendant apps
> that in turn can spawn descendant apps, and so on..
>
> The system is represented in mysql as a parent/child tree, where each
> spawned app has an ID, as well as a status for the completion status
> of the app.
>
> I'm trying to find someone I can talk to regarding this, so I can get
> clarity on how this can be implemented.
>
> The process needs to be able to:
> -update the tree tbl with updated data from the running apps
> -update the tbl with new nodes/leafs as the spawned apps are created
> -quickly return 0/1 if the descendants of a node have been complete
>
> I've created a few different tbl defs, and played with a few different
> approaches, but haven't got this right yet. I've looked at a number of
> different articles covering hierarchical, adjacency models, closures,
> etc...
>
> **The nested soln isn't applicable to the project, as the data/tree
> tbl is continually growing, which would require a complete rebuilding
> of the nested tbls, which would impose a computational/time hit on the
> process.

Right. An edge list model with a mix of MySQL stored procs and app 
functions should do the job, see 
http://www.artfulsoftware.com/mysqlbook/sampler/mysqled1ch20.html.

PB

------

>
> I can provide the sample tbl defs/data that I'm using, as well as more
> data on what I'm trying to accomplish.
>
> So, if you're skilled in this area, let's talk.
>
> Thanks
>
> -bruce
>