What Is Index Scan?
An index scan retrieves rows using a PostgreSQL index instead of scanning the full table. It improves performance for selective queries. Indexes must match the WHERE clause for the scan to be used.
Why It Matters for PostgreSQL Performance
In PostgreSQL performance work, Index Scan affects throughput, latency, or operational reliability depending on workload and configuration.
Practical Benchmarking Context
When benchmarking with pgbench, track how Index Scan changes behavior across scale factor, client concurrency, and storage conditions.
Use this term together with workload shape, concurrency level, and scale factor when interpreting pgbench outputs. Isolated values can be misleading without full run context.
Example
Analyze: Use EXPLAIN to confirm index usage.