An index is a database object that improves the speed of data retrieval operations on a table. PostgreSQL provides several specialized index types, each optimized for different data structures and query patterns. ![[assets/ex_index_only_scan.svg|300x300]] ### ![[Structures/Index/BTree]] ### ![[Structures/Index/Hash]] ### ![[Structures/Index/GIN]] ### ![[Structures/Index/GiST]] ### ![[Structures/Index/SPGiST]] ### ![[Structures/Index/BRIN]] ### ![[Structures/Index/HNSW]] ### ![[Structures/Index/IVFFLAT]]