For info, I was able to achieve this by subclassing Calcite’s Driver class and implementing my own driver which registers my Schema objects on the CalciteConnections it creates before returning them to the client.
I was then able to use a jdbc URL to use this same Driver class from both the Avatica Server and from the local service’s DataSource, and share the same Schema objects across all connections. Nick On 18/09/2017, 11:40, "Nick Stephen" <[email protected]> wrote: Thx for the quick responses. Today I have one or more local CalciteConnections (created by my data source implementation) each of which, at the time of creation, I register a small number of my own schemas. The schemas are read-only from the database connection (but their contents can evolve since they map to underlying heterogeneous data sources). I’m already reusing the schemas between these connections from this DataSource, initial tests show it working fine, but it’s not stress tested, and I’ve no thread safety in there yet (maybe not required as it’s not mutable). If I want to also expose this over JDBC avatica, then I need an avatica Meta object to be manipulating a CalciteConnection which I can configure to pre-seed with my multiple Schemas. The CalciteMetaImpl class looked interesting until I discovered it takes a CalciteConnectionImpl parameter which is package protected so I can’t unwrap my connection to this class type. Is there another way of populating the avatica server with a calcite connection which I can configure myself? (ideally I’d get this from my DataSource which is also used for local connections). Many thanks, Nick On 18/09/2017, 09:30, "Julian Hyde" <[email protected]> wrote: That's not true. You can use a Schema from multiple connections. Obviously you're responsible for thread safety if the Schema is mutable. Julian > On Sep 17, 2017, at 11:49 PM, Christian Beikov <[email protected]> wrote: > > I might be wrong, but as far as my knowledge goes, you can't have more than > a single connection to the same schema right now. I am planning to work on > that soon by implementing a datasource. As part of that I would take a look > at how Aviatica's remote capabilities fit into. Until then, I'd rather > stick to testing for now. > > Regards, > Christian > > > Am 18.09.2017 8:36 vorm. schrieb "Nick Stephen" <[email protected]>: > > Hi folks, > > We’ve started experimenting with Calcite for some work and have been > running it in-process using a datasource wrapped around a local connection > (using jdbc:calcite). > > I’d now like to expose this same database remotely using avatica, but can’t > see any APIs in avatica which can take a Connection object. If I create a > Meta with the same local URL then I understandably get a different DB > instance. > > Could someone point out the appropriate API, or are there any examples of > exposing a calcite DB remotely using avatica whilst still being able to use > it locally in-process to avoid the additional network hop. > > Thanks! > > Nick
