HHH-18657 Use IF EXISTS in OracleUserDefinedTypeExporter

[marschall]

Add an ´IF EXISTS´ to the DROP TYPE and DROP FUNCTION statements in OracleUserDefinedTypeExporter if the dialect supports it (23+ .)

https://hibernate.atlassian.net/browse/HHH-18657

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[gavinking]

LGTM, thanks!

[marschall]

One of the Oracle builds fails with

oracle.net.ns.NetException: ORA-12514: Cannot connect to database. Service freepdb1 is not registered with the listener at host localhost port 1521. (CONNECTION_ID=cf0HirgGQ/6F/E1LvtRxnQ==)
                https://docs.oracle.com/error-help/db/ora-12514/

I don't think this is related. Rather it looks to me as if a container is not yet started. Is there ar way to re-run this build?

[gavinking]

I don't think this is related.

Very unlikely to be related.

Is there ar way to re-run this build?

I restarted it.

[marschall]

I restarted it.

Thanks. It's green now.