Selecting the record I've just inserted?

[eluser]KeyStroke[/eluser]
I'm using active records in CI to insert records.

In one table, the ID is a primary key set to auto-increment, so I just leave it empty while inserting and the database will assign an ID number for it.

However, I have to use that same ID to insert a record into a related table right after that.

My question is, how do I select the ID of the record I've just inserted?


Thanks in advance!