Every query (reads and writes) saves and restores cursors to support yielding. When restoring the cursor, we reposition it by calling search_near() on the _lastReturnedId which we stored when we called next() prior to yielding the cursor.

We can use bounded cursors to improve the performance when repositioning the cursor in the WT record store. This could be useful for example for capped collections when we're making a lot of deletes and the cursor unnecessarily traverses the deleted records to reposition itself.