existing DB: how to begin...

[Wolf Benz <eu...@gmail.com>]

Hi List,

I guess I have a very common question:
Is it possible to use JSR-170 when your data ALREADY EXISTS...?
How you you map thsi then? ("this" being yr brand new nodes you wish  
to use in yur new apps & your old DB-data)
Thanks for suggestions!
Wolf

Re: existing DB: how to begin...

[Wolf Benz <eu...@gmail.com>]

Jukka,
Do you know of any such efforts going on in the current JSR-283 spec?
Wolf
___________
On 06 Feb 2007, at 22:11, Jukka Zitting wrote:

Hi,

On 2/6/07, Wolf Benz <eu...@gmail.com> wrote:
> That's indeed what I meant :-)
> The reply's not what I had hoped for, but thx anyway!
> If only because this is always the question you get when you try to
> pomote "JCR": "can we reuse our old data?" (which is, business wise,
> a perfectly valid question as well!!)
> --> From yr reply I think the reply to this one is then: yes, but not
> without serious (one-time)support of a DBA that does a one-time
> migration...

I hear you, I've seen the same issue come up repeatedly. A JDBC-JCR
bridge, even if just a read-only level 1 implementation, would be a
very cool thing to have. I recently had some success to implementing
such a bridge for XML documents (which of course are much closer to
the JCR data model), so I wouldn't be surprised if sooner or later we
did have a JDBC bridge, but as of now the best option probably a
one-time migration as you mentioned.

BR,

Jukka Zitting

Re: existing DB: how to begin...

[Jukka Zitting <ju...@gmail.com>]

Hi,

On 2/6/07, Wolf Benz <eu...@gmail.com> wrote:
> That's indeed what I meant :-)
> The reply's not what I had hoped for, but thx anyway!
> If only because this is always the question you get when you try to
> pomote "JCR": "can we reuse our old data?" (which is, business wise,
> a perfectly valid question as well!!)
> --> From yr reply I think the reply to this one is then: yes, but not
> without serious (one-time)support of a DBA that does a one-time
> migration...

I hear you, I've seen the same issue come up repeatedly. A JDBC-JCR
bridge, even if just a read-only level 1 implementation, would be a
very cool thing to have. I recently had some success to implementing
such a bridge for XML documents (which of course are much closer to
the JCR data model), so I wouldn't be surprised if sooner or later we
did have a JDBC bridge, but as of now the best option probably a
one-time migration as you mentioned.

BR,

Jukka Zitting

Re: existing DB: how to begin...

[Wolf Benz <eu...@gmail.com>]

That's indeed what I meant :-)
The reply's not what I had hoped for, but thx anyway!
If only because this is always the question you get when you try to  
pomote "JCR": "can we reuse our old data?" (which is, business wise,  
a perfectly valid question as well!!)
--> From yr reply I think the reply to this one is then: yes, but not  
without serious (one-time)support of a DBA that does a one-time  
migration...

Wolf

On 06 Feb 2007, at 13:23, Jukka Zitting wrote:

Hi,

On 2/5/07, Wolf Benz <eu...@gmail.com> wrote:
> I guess I have a very common question:
> Is it possible to use JSR-170 when your data ALREADY EXISTS...?
> How you you map thsi then? ("this" being yr brand new nodes you wish
> to use in yur new apps & your old DB-data)

You mean you have a custom database schema and want to access it
through the JCR API? Unfortunately I don't know of any JCR
implementations that currently do this.

BR,

Jukka Zitting

Re: existing DB: how to begin...

[Jukka Zitting <ju...@gmail.com>]

Hi,

On 2/5/07, Wolf Benz <eu...@gmail.com> wrote:
> I guess I have a very common question:
> Is it possible to use JSR-170 when your data ALREADY EXISTS...?
> How you you map thsi then? ("this" being yr brand new nodes you wish
> to use in yur new apps & your old DB-data)

You mean you have a custom database schema and want to access it
through the JCR API? Unfortunately I don't know of any JCR
implementations that currently do this.

BR,

Jukka Zitting