Thanks Julian,

yes we would need just (2). We could try to contribute by providing a patch
for (2) if that is of interest. Maybe we could split the issue CALCITE-482
in three sub-issues ?

Also, given that we would have to wait for a new release of Calcite that
includes this patch, would it be possible on our side to implement this as
a custom metadata instead of a BuiltInMetadata ? I have tried to find an
example of such a custom metadata extension, but haven't found anything.


On Thu, Jul 6, 2017 at 7:33 PM, Julian Hyde <[email protected]> wrote:

> I think you’re talking about SQL hints. It’s a feature that has been
> talked about several times but has never been implemented. See
> https://issues.apache.org/jira/browse/CALCITE-482 <
> https://issues.apache.org/jira/browse/CALCITE-482>.
>
> The full feature would require (1) extension to the parser to read hints,
> (2) a way of annotating RelNodes with hints, (3) changes to
> SqlToRelConverter propagate hints from the parse tree to the RelNode tree,
> but I think you need just (2). I’ll add some remarks on the JIRA case, and
> let’s discuss further there.
>
> Julian
>
>
>
> > On Jul 6, 2017, at 7:53 AM, Renaud Delbru <[email protected]>
> wrote:
> >
> > Hi,
> >
> > When creating a logical tree from our parse tree, we would like to be
> able
> > to attach metadata information to the logical rel node. For example, a
> user
> > could specify a particular algo to use for a join (e.g., hash join, merge
> > join, etc.), and we would need to attach this information to the
> > LogicalJoin node in order to have access to it when creating the physical
> > tree. What would be the correct approach to do that ? Are there examples
> > available somewhere that we can look at for inspiration ?
> >
> > Thanks
> > Kind Regards
> >
> > --
> > *Renaud Delbru*   Siren Solutions - CTO
> > T +353 91704885 |
> > [email protected] | http://siren.solutions/
> > Unit 13 GTC, Mervue Park, Galway, Ireland
>
>


-- 
*Renaud Delbru*   Siren Solutions - CTO
T +353 91704885 |
[email protected] | http://siren.solutions/
Unit 13 GTC, Mervue Park, Galway, Ireland

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