See this chat for additional context: https://debezium.zulipchat.com/#narrow/stream/348250-community-oracle/topic/Metrics.20for.20long-running.20transactions

Currently, the Oracle connector has different JMX metrics relating to transactions. For example, NumberOfActiveTransactions shows the number of active transactions for the connector. It'd be useful to have a metric which shows the current duration of the longest-running of these active transactions.

Use-Case: Most Databases have policies around the number of archive logs that are stored before being deleted. If the duration of a transaction is longer than the amount of time an archive log is stored on disk, this will lead to the connector crashing as the log for the long-running transaction has been removed. A metric would allow users to proactively handle these long-running transactions by either killing the transaction or ensuring that logs aren't deleted before the transaction completes.