Adding support for InterSystems IRIS dialect

[bdeboe]

This Pull Request adds DDL files generated for the new InterSystems IRIS dialect recently added to SqlRender per OHDSI/SqlRender@e5463e2, to address #716

[bdeboe]

The additional unit tests (off by default per the testDatabases <- c("postgresql") in setup.R) rely on the following environment variables:

CDMDDLBASE_IRIS_URL
CDMDDLBASE_IRIS_USER
CDMDDLBASE_IRIS_PASSWORD
CDMDDLBASE_IRIS_CDM_SCHEMA

I can provide values for these to reach our test server through email to the repo admin if needed, though this whole thing is pending a PR for the OHDSI/DatabaseConnector repo.

[bdeboe]

OHDSI/DatabaseConnector#302 was just approved and is now part of DatabaseConnector 6.4. Hopefully that means this PR can now also proceed?

[clairblacketer]

Thanks @bdeboe. Can you confirm that there is an OHDSI iris testing environment?

[bdeboe]

yes, I passed the connection details on to @schuemie a month or so ago for inclusion in the DatabaseConnector test suite.
Do you also want to include IRIS in the CDM regression tests? If so, what kind of schema/database setup would you like (I assume something independent of what the DatabaseConnector tests would see). I can set that up and send you the details through email.

[schuemie]

We have the following secrets set for testing in the OHDSI GitHub organization:

• CDM_IRIS_CDM_SCHEMA
• CDM_IRIS_CONNECTION_STRING
• CDM_IRIS_OHDSI_SCHEMA
• CDM_IRIS_PASSWORD
• CDM_IRIS_USER

I guess we need an empty schema for testing the DDL? Else we could use CDM_IRIS_OHDSI_SCHEMA

[bdeboe]

Schemas don't need to be created upfront in IRIS, so you can use anything you prefer that wouldn't get in the way of DatabaseConnector's use of the database (which I believe will use the contents of the CDM_IRIS_CDM_SCHEMA env variable / secret). I could also create a separate database (with its own connection string) that'd offer more isolation, but that's probably overkill if we just pick a separate schema name.

[schuemie]

If we use CDM_IRIS_CDM_SCHEMA that will conflict with the existing tables in that schema which are used for unit testing by other packages, right?

Are you saying we could create a new schema on the fly just for testing the DDL?

[bdeboe]

that is correct.

-- this should just work:
CREATE TABLE MyNewSchemaForMarch12.COHORT ...;

-- and this is probably a good idea at the end
DROP SCHEMA MyNewSchemaForMarch12;

[schuemie]

Thanks! Could you modify the PR to reflect these changes and use the secrets as specified?