B Tree vs B+ Tree Key Differences and When to Use
A B Tree stores both keys and data in every node, while a B+ Tree keeps only keys in internal nodes and moves all data to leaf nodes, linking those leaves together.
People confuse them because they look alike on paper, but the moment you need fast range scans in a database index, the B+ Tree’s linked leaves make a huge difference in everyday queries.
Key Differences
B Tree stores data at every level; B+ Tree stores data only at leaf nodes. Leaves are linked in B+ Tree for sequential access, making range queries quicker, whereas B Tree requires deeper traversal for the same task.
Which One Should You Choose?
Use B+ Tree when your workload involves many range searches, like listing all users between ages 25 and 40. Stick with B Tree if your lookups are mostly single-point searches with less emphasis on scanning large ranges.
Is B+ Tree always faster?
No. For single-key lookups, both perform similarly; the speed gain appears mainly during ordered scans or range queries.
Can I switch later?
Yes, but it requires rebuilding the index, so pick the structure that matches your most common query pattern early on.