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+---
+title: Index JSONB Columns for Efficient Querying
+impact: MEDIUM
+impactDescription: 10-100x faster JSONB queries with proper indexing
+tags: jsonb, gin, indexes, json
+---
+
+## Index JSONB Columns for Efficient Querying
+
+JSONB queries without indexes scan the entire table. Use GIN indexes for containment queries.
+
+**Incorrect (no index on JSONB):**
+
+```sql
+create table products (
+  id bigint primary key,
+  attributes jsonb
+);
+
+-- Full table scan for every query
+select * from products where attributes @> '{"color": "red"}';
+select * from products where attributes->>'brand' = 'Nike';
+```
+
+**Correct (GIN index for JSONB):**
+
+```sql
+-- GIN index for containment operators (@>, ?, ?&, ?|)
+create index products_attrs_gin on products using gin (attributes);
+
+-- Now containment queries use the index
+select * from products where attributes @> '{"color": "red"}';
+
+-- For specific key lookups, use expression index
+create index products_brand_idx on products ((attributes->>'brand'));
+select * from products where attributes->>'brand' = 'Nike';
+```
+
+Choose the right operator class:
+
+```sql
+-- jsonb_ops (default): supports all operators, larger index
+create index idx1 on products using gin (attributes);
+
+-- jsonb_path_ops: only @> operator, but 2-3x smaller index
+create index idx2 on products using gin (attributes jsonb_path_ops);
+```
+
+Reference: [JSONB Indexes](https://www.postgresql.org/docs/current/datatype-json.html#JSON-INDEXING)