PostgreSQL's JSONB type combines document flexibility with relational power. Store semi-structured data alongside traditional columns. Query JSON fields with powerful operators. Create indexes for performant JSON queries.
JSONB Operations
JSONB stores JSON in efficient binary format. Extract values with -> and ->> operators. Update nested values with jsonb_set. Aggregate JSON with jsonb_agg. These operations integrate naturally with SQL.
- Use JSONB over JSON for most cases—better performance and indexing
- Extract values with ->> for text, -> for JSON objects
- Create GIN indexes on JSONB columns for containment queries
- Use jsonb_path_query for complex JSON traversal
- Validate JSON schema with check constraints
When to Use JSON
JSON suits truly variable attributes—user preferences, metadata, logs. Avoid JSON for data you'll frequently filter or join—traditional columns perform better. Balance flexibility against query performance.