Miguel,

For those of us who don't know: what is a "star configuration"?

Thanks,
Warwick


> -----Original Message-----
> Hello Carlos,
> 
>  After a little time working the insides of the standard 
> rdbms adaptor, I've found out that, like you're stating, that 
> those two tables are not redundant, but required. That 
> troubles me immensely since an operation in a directory might 
> influence its children. The Slide implementation, since it 
> doesn't know if it will influence children or no, it does 
> some database query/updates just-in-case. That produces a 
> very high number of queries to the database, higher means a 
> directory with higher number of children. Also, we have 
> noticed that if the implementation must update a node, he 
> does not update it (doesn't care of the state of the node 
> either), it just replaces it. That also might imply updates 
> in other nodes that refer to first one, so we end up in a 
> roundabout play that will consume time in the delivery of the 
> initial request.
> 
>  I remember that a while back, someone submitted some patches 
> to improve database performance (around last October I 
> believe). Does someone know the state of that affair?
> 
>  I'm starting to think that, although the present db schema 
> is consistent, we should allow it some redundant information, 
> so we wouldn't need to perform so many queries for every 
> object. What about a star configuration, used in dataware housing?
> 
>  BTW, I got puzzled by that link table and when I started to 
> search the slide mailing list, I've found an email by a 
> fellow (can't recall the name) referencing the rfc 2518, 
> section 4.6 - Media Independent Links, witch seems to match 
> this link table. Seems that a link is a kind of an hyperlink 
> in a html page...
> 
> Many thanks,
> Miguel Figueiredo
> 
> _____
> 
> As I understand, binding and parent_binding are used to implement the 
> resource hierarchy (parent/child relationships) and both are always 
> required. They have nothing to do with the binding concept in 
> the WebDAV 
> spec. The table LINKS is what implements the binding functionality in 
> the spec. If binding is not enabled in the Slide 
> configuration the LINKS 
> table is not used.
> 
> Carlos
> 
> 
> 
> Miguel Figueiredo wrote:
> >  Hello folks,
> > 
> >  We are in the process of creating an optimized postgres adapter. 
> > While analyzing the slide's DB schema we found out that 
> there are two 
> > tables
> that
> > seem to be redundant:
> > 
> >  * the binding table:
> >     CREATE TABLE BINDING (
> >     URI_ID         integer                  NOT NULL  REFERENCES
> > URI(URI_ID), 
> >       NAME           text           NOT NULL,
> >       CHILD_UURI_ID  integer                NOT NULL  REFERENCES
> > URI(URI_ID), 
> >       PRIMARY KEY    (URI_ID, NAME, CHILD_UURI_ID) 
> >     );
> > 
> >  * the parent_binding table:
> > 
> >     CREATE TABLE PARENT_BINDING (
> >         URI_ID        integer          NOT NULL  REFERENCES  URI
> > (URI_ID),
> >         NAME          text             NOT NULL, 
> >         PARENT_UURI_ID integer         NOT NULL  REFERENCES  URI
> > (URI_ID),
> >         PRIMARY KEY    (URI_ID, NAME, PARENT_UURI_ID)
> >     );
> > 
> >  The name binding suggests that it may represent the several binds
> > (shortcuts) that a resource may be linked to. But it can 
> also mean the 
> > resource's children in case of a collection. If the second is true, 
> > the table parent_binding suggests being the reference to the 
> > resource's parent collection.
> > 
> >  Also, the table links:
> > 
> >     CREATE TABLE LINKS (
> >         URI_ID          integer        NOT NULL  REFERENCES  URI
> > (URI_ID),
> >         LINK_TO_ID      integer        NOT NULL  REFERENCES  URI
> > (URI_ID),
> >         UNIQUE (URI_ID, LINK_TO_ID)
> >     );
> > 
> >  Seems to give a hint that this may be the table where bindings
> (shortcuts)
> > of a resource are stored. When I exam it, the table is 
> empty, no data 
> > stored, witch may be expected since the postgres adapter is not 
> > prepared
> to
> > support the dav binding spec.
> > 
> > Can anyone give me some insight?
> > 
> > Many thanks,
> > Miguel Figueiredo
> > 
> > 
> > 
> > 
> > 
> ---------------------------------------------------------------------
> > To unsubscribe, e-mail: [EMAIL PROTECTED]
> > For additional commands, e-mail: [EMAIL PROTECTED]
> > 
> > 
> 
> 
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: [EMAIL PROTECTED]
> For additional commands, e-mail: [EMAIL PROTECTED]
> 
> 
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: [EMAIL PROTECTED]
> For additional commands, e-mail: [EMAIL PROTECTED]
> 
> 

---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]

Reply via email to