Re: GDL2 How-To

[Dirk Lattermann]

Hello Frédéric!


On 2003-08-21 16:34:08 +0200 Frédéric PRACA <frederic.praca@freebsd-fr.org> 
wrote:

> Hi everybody,
> I just started looking at GDL2 which seems to be the most powerful layer 
> between objects and relationnal databases I've seen.

How did you find this out without docs? :-)

> Well, I have problems :
> - First, there's no doc with it nor examples. So I read the doc from db and 
> the examples which are almost good fro gdl2
> - Second, after reading everything and keeping it like handbook, I didn't 
> found anywhere how to simply select and retrieve objects from my little 
> database. No how-to, nothing ... Well looking in header files, I found some 
> methods in DatabaseChannel but specifying entities in the request seems 
> redundant to me (I already described it in the model file with the mapping).
> Does someone know where I can find help or a little example well commented 
> with application objects and how to retrieve them from the database ?
> Thanks a lot

It can be a bit overwhelming at first. I recently discovered GDL2 myself and 
found that the best docs were the ones from Apple, indeed. This reminds me that 
I intended to write something about my experiences trying it out, but I didn't 
get to it... :-(

> 
> Fred
> 
> PS: please don't give the links on developer.apple.com, everything about EOF 
> is in WebObjects and is now in Java.

I will give you the links anyway, after the restructuring of Apple's pages, the 
legacy WebObjects 4.5 docs together with ObjC-EOF are again available:

http://developer.apple.com/documentation/WebObjects/Legacy/WebObjects_4.5/webobjects.html

The document that helped me most is the EOF Developer's Guide in the section 
"Understanding WebObjects" of that page. The rest is EOControl and EOAccess, in 
the section "Objective-C Framework Reference".

Hope this helps, hoping that Apple's docs will stay there on their page for a 
while, and sorry I didn't get to writing the GDL2 tutorial,

Cheers,
Dirk