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Date: Mon, 21 Jun 2010 11:35:13 +0200
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Subject: Re: Can anybody explain this (related to javax.jcr.query)
From: Alexander Klimetschek <aklimets@day.com>
To: dev@jackrabbit.apache.org
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On Mon, Jun 21, 2010 at 10:07, Subash Chaturanga <subashsdm@gmail.com> wrote:
> In JCR Queries ,say for instance
>
> " select * from nt:resource "
>
> Does this means select all nodes which has the node type "resource".

Yes, but the node type is called "nt:resource" (nt being a prefix for
a full namespace), independently of the sql query.

>As I am
> a new commer ,it is really great if anyone can tell me how to query it?
>
> I went through the JSR 283 spec ,but couldn't get an exact meaning.
> Does Selectors means the thing "select" we know in SQL queries ? Joins :
> means combining several "select" queries as in SQL ?

Yes, it follows the standard SQL semantics, albeit the feature set is
very specific to JCR.

> Is it always a set of nodes we get returned in an execute command?

Yes.

> Are there any references other than the spec to follow ?

You could look at the earlier JCR-SQL query language in JCR 1.0
(JSR-170) that is now deprecated, but still available in Jackrabbit
2.x. This is similar to JCR-SQL2, but without joins and other
features.

Regards,
Alex

-- 
Alexander Klimetschek
alexander.klimetschek@day.com