RE: DB Alternatives to DODS

I would be interested in seeing some sample code for your OR classes if it is
available…

David R Robison
Open Roads Consulting, Inc.
http://www.openroadsconsulting.com

Quoting Christian Cryder <[email protected]>:

> Hi David,
> 
> We _don't_ use DODS. I've never been much impressed with it (and I did
> a
> fair amount of work with the newest version of it while I was still at
> Lutris)...just not how I like to approach OR mapping. There are a number
> of
> other OR mapping packages out there, but most of them were heavier
> weight
> than what we wanted, so we ended up rolling our own solution, and at
> some
> point when it gets a little further along (and I get a little less
> busy), we
> may make it publically available.
> 
> What we really wanted something lightweight to map the JDBC result sets
> into
> nested list/map data structures. Specifically, we thought the data
> layer
> should
> a) make no requirements of the SQL DB structure
> b) give us complete access to the SQL layer - we write it, rather than
> letting the tool do it for us
> c) give us the ability to easily write test cases for the sql layer (so
> we
> can validate all the SQL in the app at any given point)
> d) automatically support the lazy loading of data (so that nested data
> wasn't actually loaded until it was needed) and nested transactions
> (save
> the data at any point in the hierarchy and everything below it gets
> saved)
> e) support different keying mechanisms - simple surrogate keys vs
> complex
> aggregate keys; self assigned identity keys vs. autocreated identity
> keys
> f) be very easy to program against
> 
> As an example of what we came up with, consider the following table
> structure:
> 
> 
> 
> Let's say I want to iterate through all the Terminals for Business ATMR.
> I
> would simply do this:
> 
> BusinessList list = new BusinessList();
> list.putKey(BusinessMap.COMPANY_ID, Companies.ATMR);
> list.load();
> for (int i=0; i<list.size(); i++) {
>     BusinessMap map = (BusinessMap) list.get(i);
>     String descr = (String) map.get(BusinessMap.DESCR);
>     TerminalList tlist = (TerminalList)
> map.get(BusinessMap.TERMINAL_LIST);
> 
>     ...iterate through tlist...
> 
> }
> 
> The key thing to observe here is that the properties are accessed just
> as if
> this was a regular list/map structure. As I'm looping through terminals,
> I
> can set properties as needed, then when I'm all done issue a list.save()
> and
> the whole thing will be automatically wrapped in a trx. Or I could load
> an
> individual Terminal all by itself and work with that:
> 
> TerminalMap tm = new TerminalMap();
> tm.putKey(TerminalMap.COMPANY_ID, Companies.ATMR);
> tm.putKey(TerminalMap.BUSINESS_ID, ...);
> tm.putKey(TerminalMap.TERMINAL_ID, ...);
> tm.load();
> ...modify props...
> tm.save();
> 
> The whole thing is quite flexible. Not entirely automated (in the sense
> that
> we have to write the sql code and manually create the map/list objects,
> but
> that's how we wanted it, so that we could have complete control over
> the
> thing.
> 
> So that's how we do OR mapping...
> 
> Christian
> ----------------------------------------------
> Christian Cryder [[email protected]]
> Internet Architect, ATMReports.com
> Barracuda - http://barracudamvc.org
> ----------------------------------------------
> "Coffee? I could quit anytime, just not today"
>   -----Original Message-----
>   From: [email protected]
> [mailto:[email protected]]On Behalf Of David R Robison
>   Sent: Thursday, February 27, 2003 7:26 PM
>   To: [email protected]
>   Subject: [Barracuda] DB Alternatives to DODS
> 
> 
>   In the past I've used DODS for my database access in my Barracuda
> applications. It integrates well with Enhydra and is easy to use when
> creating a new database. However, I have had trouble getting it to work
> with
> legacy databases (tables w/o the version and objected fields). Has
> anyone
> used any other tools besides DODS for database access within
> Enhydra/Barracuda?
> 
> 
> 
>   David R Robison
> 
>   Open Roads Consulting, Inc.
> 
>   http://www.openroadsconsulting.com
> 
> 
>