Re: [Springframework-developer] OT : Anyone know of a solution for storing (and retrieving) hierarchical data efficiently?

[Eduardo I. I. <zi...@su...>]

You can try using LDAP, it is well suited for hierarchical data, but it is not 
efficient when doing updates.

Another alternative would be an XML database like dbXML or Xindice. It's much 
easier doing an XPath query than traversing a complex object hierarchy.


Cameron Braid wrote:

> I am implementing a system that needs to store a fair bit of 
> hierarchical data.
> 
>  
> 
> For previous apps that have had this requirement, I stored the hierarchy 
> in relational databases, which worked sufficiently well.
> 
>  
> 
> BUT, this new application has a lot of operations that deal with deep 
> and wide directed trees (I don’t know if that is the correct name for 
> them, but I am sure you get the picture).
> 
>  
> 
> This would require a LOT of trips to the database to fetch the children 
> each time a transaction runs.
> 
>  
> 
> I could try and implement this using some complex caches but I though I 
> would see if anyone else has an alternate solution.
> 
>  
> 
> It will need to be able to participate in a distributed transaction, 
> since some data will be stored in a relational database, and some in the 
> hierarchy store.
> 
>  
> 
> I have thought of products like
> 
>  
> 
>     * Prevayler http://www.prevayler.org <http://www.prevayler.org/>
>           o seems a little amateur from the wiki
>           o seems to support transactions
>           o needs to keep all data in memory – which probably won’t work
>             for this site
>           o doesn’t seem to support JTA
>     * Berkeley DB Java Edition - http://www.sleepycat.com/products/je.shtml
>           o Supports transactions
>           o doesn’t seem to support JTA
>           o may be too low level
>     * JDBM http://jdbm.sourceforge.net/
>           o Simple transactional persistent hash map implementation
> 
>  
> 
> Does anyone have any suggestions on other ‘preferably’ open source 
> products, or techniques to achieve wish to do.
> 
>  
> 
> I am also very new to XA and distributed transactions, so if anyone has 
> any hints on using XA with spring please show me where I can find some 
> resources.
> 
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> 
> Also - it is possible to implement XA support for systems like jdbm, 
> prevayler or Berkley db ?
> 
>  
> 
> Cameron.
>