Presto Oracle connector

[sajjoseph]

Implements Oracle connector using Oracle JDBC driver. Tested against Oracle 12c even though it should work with older versions as well.

[electrum]

Thanks for contributing this!

Let's start with the obvious issue that the Oracle JDBC driver isn't available under an OSS-friendly license, thus it's not available in Maven central and we can't redistribute it with Presto. This creates some problems for us to solve:

1. How to build? We need to build Presto without the Oracle driver (e.g., Travis CI needs to pass). Fortunately, the dependency is not required for compilation, so an easy solution is to simply remove the driver dependency from the POM.

2. How do end users use it? We can include instructions in the documentation to add the Oracle driver JAR file to the plugin/oracle directory on the Presto coordinator and workers. This is really bad from a user experience, but I don't see a better alternative.

3. How do we test? We need to make sure the connector doesn't break when changes are made to presto-base-jdbc, the SPI, library upgrades, etc. Hopefully, we can test it in Travis, similar to how we do it for other integration tests. The SQL Server test is a good one to look at. Oracle seems to have some Docker images available: https://container-registry.oracle.com/

[pdanilew]

@sajjoseph: this connector would help a lot in my opinion, are you going to continue work on this PR?

[sajjoseph]

Thanks for checking my contribution and the feedback. About Problem #1, how can we avoid the dependency on Oracle Driver? In OracleClient.java, we have the following line in line #93: return new DriverConnectionFactory(new OracleDriver(), config.getConnectionUrl(), connectionProperties); I wonder, how we can resolve the name OracleDriver if we don't include the Oracle driver dependency. Please share your thoughts. About #2, I will update the README with instructions for end users to deploy the Oracle Driver file separately. For #3, I am looking into how SQL Server tests are managed in presto-product-tests module and will see if I can incorporate similar changes for Oracle.

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On Thu, Sep 27, 2018 at 10:11 AM pdanilew ***@***.***> wrote: @sajjoseph <https://github.com/sajjoseph>: this connector would help a lot in my opinion, are you going to continue work on this PR? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#11540 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AQhEuBzr_Z9iM2opTbCkwS9xLiPI4wpBks5ufPi4gaJpZM4WyFSL> .

-- Sajumon Joseph 303-378-0593 [email protected]

[sajjoseph]

#1 is fixed.

Updated the code base to remove the Oracle JDBC dependency. Travis build also is working now.

#2
Updated the documentation in README to include instructions on copying oracle jdbc driver to the distro.

#3.
Exploring this option.

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. If you'd still like this PR merged, please comment on the task, make sure you've addressed reviewer comments, and rebase on the latest master. Thank you for your contributions!