oceanbase::keybtree::ScanHandle::scan_forward

[coding01000]

When I was performing the TPCC benchmark, the scan_forward was called a lot of times,
I want to know what this function does?

[nroskill]

There are both hashtable and btree in memtable.
When it's necessary to iter btree to find the data, scan_forward will build the path (from root to leaf node) for btree iterator.

code link
https://github.com/oceanbase/oceanbase/blob/master/src/storage/memtable/mvcc/ob_keybtree.cpp#L656