Can you list the indexes available in PostgreSQL?

The following main index types are available in PostgreSQL:

• B-tree — the most common type, used for fast equality and range searches.
• Hash — an index for quick equality searches, but less versatile and used less frequently.
• GIN (Generalized Inverted Index) — suitable for indexing arrays, JSONB, full-text search.
• GiST (Generalized Search Tree) — a flexible index for working with geometric data, full-text search, and other types.
• SP-GiST (Space-partitioned GiST) — a specialized index for structures with sparse data, such as points in space.
• BRIN (Block Range INdexes) — a compact index for very large tables with ordered data.

Example of creating a B-tree index:

CREATE INDEX idx_users_email ON users USING btree(email);