IN ORACLE,
I'm looking for a SQL statement for the following

record count of a dataset that is created on the back-end where no return set is brought to the front-end. Therefore reccount() won't work. I also don't want to use SELECT count(*) because that may take longer than desired if the dataset is 500,000+ records...
In SQL-Server, I know about and use SP_SPACEUSED and grab rows column.

I also need a query to return indexes on a given table with their expressions. In SQL-Server, I use SP_HELPINDEX...

TIA