Hi Julian,
I apologize for the same.

It was not my intention to do so. I very much wanted to acknowledge the
replies, however, I could not do so as mentioned on my 2nd post:
https://lists.apache.org/thread/27v6pymkm8qfxfkrf2pojl8w1bpmjwzc (I asked
for instructions on replying back to the mailing list on this as well).

Failing to get a reply for that, I had to send emails to the mailing list
again (I tried subscribing but the system is demanding some kind of SSO
login).

Could you please tell me how to subscribe? I will then reply to the
particular queries I had on each post.

Thanks & Regards,
Pranav





On Fri, Aug 5, 2022, 2:06 PM Julian Hyde <[email protected]> wrote:

> Pranav,
>
> Please subscribe to this list. You have asked several questions, received
> replies, not acknowledged those replies, and asked further questions. Also,
> since you are not subscribed, each email you post has to go through manual
> moderation.
>
> Julian
>
> > On Aug 5, 2022, at 9:38 AM, Pranav Deshpande <
> [email protected]> wrote:
> >
> > Dear Apache Calcite Team,
> > I have 2 questions.
> >
> > ---------------------------------
> > 1.
> >
> > There are plenty of examples on how to push down projects and filters
> into
> > the leaf nodes (tablescans).
> >
> > However, I could not find any examples to push down joins to TableScans
> (or
> > joins+filters+projects etc.) [this is helpful for data federation I
> think].
> >
> > On the mailing list, many folks are suggesting that I use Drill. However,
> > the purpose of my exercise is to gain knowledge about DBMS and Query
> > processing etc.
> >
> > I tried debugging open source engines that use Calcite (Drill, Druid,
> Trino
> > etc.) but was completely lost.
> >
> > Any examples/pointers/guidance around the same would be appreciated.
> > Example, pushing down a join with a filter to a DBMS(consider jdbc
> > msql etc.)
> >
> > -------------------------------------
> > 2.
> >
> > The 2nd question I have is regarding conventions and different DBMS. The
> > cluster has a method to replace the trait convention(Bindable,JDBC etc.),
> > and then we optimize and get the physical plan.
> >
> > But imagine I have both the MYSQL JDBC convnction and a cassandra
> > convention and some user is trying to query both tables.
> >
> > Something like "SELECT users.username, specialdata.country from
> > cassandraDB.user join mysqlDB.specialdata ON users.id
> =specialdata.userid"
> >
> > Now, how will calcite do the optimization here? The planner is not
> > accepting 2 different conventions.
> >
> > Thanks & Regards,
> > Pranav
>
>

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