Track and Optimize Index Performance with System Stats

Monitoring Index Usage

Write a PostgreSQL query to retrieve index usage statistics from the system catalog.

Solution:

-- Specify the action to query index usage statistics.
SELECT * 
-- Define the source table containing the statistics.
FROM pg_stat_user_indexes 
-- Add a condition to filter statistics for the Employees table.
WHERE relname = 'employees';

Explanation:

• Purpose of the Query:
• To monitor and analyze how often each index is used in queries.
• Key Components:
• pg_stat_user_indexes : A system view that tracks user index statistics.
• WHERE relname = 'employees' : Filters the data for the Employees table.

Notes:

• Use this query to identify unused indexes that might be candidates for removal.
• Monitoring index usage helps in optimizing database performance.

For more Practice: Solve these Related Problems:

• Write a PostgreSQL query to retrieve index usage statistics for the "Users" table from pg_stat_user_indexes.
• Write a PostgreSQL query to display index scan counts for the "Orders" table using pg_stat_all_indexes.
• Write a PostgreSQL query to check index usage details for the "Products" table from pg_stat_user_indexes.
• Write a PostgreSQL query to list index usage statistics for all tables in the current database from pg_stat_user_indexes.

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