Intermediate
Database Management Systems
Q54 / 100
What is the purpose of database statistics?
Correct! Well done.
Incorrect.
The correct answer is B) Metadata about data distribution (row counts, value frequencies, histograms) used by the query optimizer to choose efficient execution plans
B
Correct Answer
Metadata about data distribution (row counts, value frequencies, histograms) used by the query optimizer to choose efficient execution plans
Explanation
Statistics (e.g., pg_statistics in PostgreSQL) inform the optimizer about actual data distribution. Stale statistics cause bad query plans. ANALYZE (PostgreSQL) or UPDATE STATISTICS (SQL Server) refresh them.
Progress
54/100