Lesson 7 of 81972–today7 min
Indexes and query plans
In 1970, at Boeing's research laboratories, Rudolf Bayer and Edward McCreight described a tree built for disks rather than memory; the paper appeared in Acta Informatica in 1972. Disks read whole blocks at a time, and each read costs far more than any comparison in memory, so the right tree is short and wide.
The paper never says what the B stands for. Whatever it means, the B-tree and its variant the B+ tree became the default index of almost every relational database.
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Sources
- Organization and Maintenance of Large Ordered Indexes (R. Bayer and E. McCreight, Acta Informatica 1, 1972) — Springer
- PostgreSQL documentation: Index Types — PostgreSQL Global Development Group
- PostgreSQL documentation: Using EXPLAIN — PostgreSQL Global Development Group
- Query Planning — SQLite