Query Planning & Statistics (EXPLAIN ANALYZE) Quiz Home › PostgreSQL DBA › Query Planning & Statistics (EXPLAIN ANALYZE) 🔍 Postgres Database Administration – Query Planning & Statistics (EXPLAIN ANALYZE) 20 questions · 15 min timer · Explanations included · Free 1. Why might an index scan be slower than a sequential scan in some cases? Index scans require more CPU resources than sequential scans. Index scans can involve more random I/O operations than sequential scans. Index scans are not supported for large tables. Indexes are always stored on slower disk partitions. None Show Hint Index scans can involve more random I/O operations, which may be slower than the sequential I/O operations of a sequential scan. 2. What role does the 'random_page_cost' parameter play in query planning? It sets the maximum number of pages that can be read randomly. It influences the planner's preference for index scans over sequential scans. It controls the frequency of autovacuum operations. It determines the cost of sequential I/O operations. None Show Hint The 'random_page_cost' parameter influences the planner's decision to prefer index scans over sequential scans by setting the cost of random I/O operations. Loading questions... Loading questions... Loading questions... Loading questions... Loading questions... Loading questions... Loading questions... Loading questions... Loading questions... Loading questions... Loading questions... Loading questions... Loading questions... Loading questions... Loading questions... Loading questions... Loading questions... Loading questions... Click Submit to see your final score! Previous Start Quiz Next Time's up
