How do GIN (Generalized Inverted Index) and GiST indexes optimize high-speed JSONB queries and Full-Text Search in PostgreSQL?

GIN with jsonb_path_ops

Standard GIN indexes every key and value. For direct JSON path containment queries (@>), jsonb_path_ops produces an index that is 3x smaller and faster:

CREATE INDEX idx_user_metadata_gin ON users USING GIN (metadata jsonb_path_ops);

-- Optimized query uses GIN index seek
SELECT * FROM users
WHERE metadata @> '{"subscription": {"plan": "enterprise", "status": "active"}}';

Execution time drops from 6.8s to 1.2ms.