← Advanced DBMS learning pathAdvanced DBMS · Module 2 of 10
Indexing structures
Speed up queries with B+ trees and hashing.
📖 Key ideas
- Indexes map key values to record locations.
- B+ trees keep data sorted with all records at leaves; great for range queries.
- Hash indexes give fast equality lookups.
- Clustered index orders the table data; non-clustered points to data.
- Indexes speed reads but slow writes.
💡 Real-life example: A B+ tree index is a multi-level book index: chapter, then page, then line.
B+ treeBalanced tree index with leaf-level data
Hash indexIndex using hashing
Clustered indexDetermines physical row order
Secondary indexAdditional index on other columns