Thanks! That makes sense.
Avatica supports the commit() call, but not Calcite :)
Sitting in a coffee shop killing time. Let me see if I can knock out
CALCITE-2065 ;)
On 11/22/17 11:52 AM, Christian Tzolov wrote:
Hi Josh,
Here
is
Z
eppelin
's JDBC Interpreter forcefull auto-commit implementation
:
http://bit.ly/2zrykP9
So if the connection is not auto-commit = true the JDBC interpreter will
forcefully call commit.
But Avatica's connection defaults to auto-commit = true and there is no way
to configure it from the properties! I can not call
Connection#setAutoCommit(boolean) without the Zeppelin's generic JDBC
interpret implementation. There is ZEPPELIN-2451 issue that tries to
address this but i'm not sure the approach is right (see my comment in
https://github.com/apache/zeppelin/pull/2396)
The connection.commit() called by Zeppelin hits the CalciteMetaImpl#commit
(). Later throws an explicit
UnsupportedOperationException
. E.g.
@Override public void commit(ConnectionHandle ch) {
throw new UnsupportedOperationException();
}
On 22 November 2017 at 17:11, Josh Elser <els...@apache.org> wrote:
Hey Christian,
Thanks for sharing this. Sounds cool.
I'm curious what you mean when you say that the Avatica connection doesn't
support commit. This was implemented in CALCITE-767.
Also, is there a reason that Zeppelin needs a property to control
autoCommit and can't use the Connection#setAutoCommit(boolean) method?
On 11/22/17 8:09 AM, Christian Tzolov wrote:
FYI,
you can use the Apache Zeppelin's generic JDBC interpreter to plug a
Calcite based JDBC adapter.
Here are my results of plug-in the Geode-Calcite adapter:
https://www.linkedin.com/pulse/advanced-apache-geode-data-
analytics-zeppelin-over-sqljdbc-tzolov/
Although i've been testing with particular adapter i believe the approach
and the findings would be applicable for any Avatica JDBC adapter too.
The only minor but blocking !!! issue is related to the fact that
Zeppelin's JDBC interpreter tries to 'commit' the jdbc connection if later
is not set as 'auto-commit=true'. But the Avatica connection does NOT
support commits.
At the moment there is no way to switch this behavior off on the Zeppelin
side. The ZEPPELIN-2451 issue and PR hopefully will resolve this.
Unfortunately Avatica doesn't provide properties to set the auto-commit to
true (default is hardcoded to false).
As a temporal solution you can build Zeppelin from my fork (
https://github.com/tzolov/zeppelin/tree/calcite) and play with Zeppelin
and
Calcite adapters.
Cheers,
Christian
