• B-tree: implements Balanced Tree indexing
  • hash: implements indexing by calculating hashes, which can only handle simple equality comparisons
  • GiST: implements Generalized Search Tree, a University of California Berkely project called The GiST Indexing Project
  • SP-GiST: implements space-partitioned GiST, which facilitate development of a wide range of different non-balanced data structures, such as quad-trees, k-d trees, and suffix trees (tries)
  • GIN: implements generalized inverted index, designed for handling cases where the items to be indexed are composite values
  • BRIN: implements block range indexes, which stores summaries about the values stored in consecutive physical block ranges of a table
  • PostgreSQL: Documentation: 16: Chapter 11. Indexes