Databases · Senior · Question 6 of 75

How do B-tree storage engines and LSM-tree storage engines differ for writes?

1B-trees are only used in NoSQL databases
✓Correct answer: B-trees update pages in place; LSM trees append to memory and sorted files that are merged later, which makes writes cheaper but reads and compaction more complex
3LSM trees can't store sorted data

Explanation

Cassandra, RocksDB and ScyllaDB use LSM trees for write-heavy workloads. PostgreSQL and MySQL InnoDB use B-trees.

Further reading

Test yourself

Take the Databases · Senior quiz: questions and options are shuffled, and you get a review of your mistakes at the end.