You don't ever need to know what search driver is being used to implement a search content provider.
You just need to make sure either 1) the service contracts are defined or 2) the search callbacks are define for the search datasource and url.
After that you need to make sure the items are inserted into the search observer queue when they are added updated or deleted.
The documentation is here: https://openacs.org/search/doc/guidelines.html
Obviously you can use the tcl api for service contracts, which is much easier and database neutral. I am pretty sure this is already done.
So specifically for bugtracker you need to 1) make sure the search triggers are implemented and 2) make sure the procedures that implement the search service contracts have oracle support for the queries.
